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Belyaev AM, Skopin II, Lobacheva GV, Alshibaya MD. The combination of Euroscore II with a new variable "Nongraftable coronary artery lesions" improves the discriminating power of the test in surgical patients with postinfarction ventricular septal defect and ventricular aneurysm. J Card Surg 2022; 37:4952-4961. [PMID: 36378876 DOI: 10.1111/jocs.17181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Accepted: 10/27/2022] [Indexed: 11/16/2022]
Abstract
BACKGROUND We aimed to establish whether Euroscore II can be used for the prediction of hospital mortality in surgical patients with postinfarction intraventricular septal defect (PIVSD) and ventricular aneurysm (VA), and coexisting coronary artery lesions (CALs), and identify perioperative mortality risk factors to improve the discriminating power of Euroscore II. METHODS This was a retrospective observational study. The inclusion criterion was PIVSD. Exclusion criteria were previous CABG, conservative treatment, percutaneous transcatheter closure of PIVSDs, and PIVSDs with normal coronary arteries on coronary angiography. RESULTS Among 53 patients with PIVSDs and VAs who met eligibility criteria, 12 (22.6%) patients died in the hospital. Logistic regression demonstrated that Euroscore II was associated with in-hospital mortality (odds ratio [OR] = 1.13; 95% confidence interval [CI]: 1.03-1.23; p = .006), well-calibrated (Hosmer-Lemeshow χ2 (8) = 9.75; p = .283), and had fair discriminating power, area under receiver operating characteristic curve (AUC) = 77% (95% CI: 58%-96%). A newly identified variable "Nongraftable CALs" was associated with in-hospital mortality (OR = 6.65; 95% CI: 1.24-35.53; p = .027), and had a fair discriminating power, AUC = 70% (95% CI: 54%-85%). When Euroscore II and Nongraftable CALs were combined, the discriminating power of the test increased to 83% (95% CI: 71%-95%), p = .036. CONCLUSION Euroscore II has adequate discriminating power and good calibration in predicting in-hospital mortality of surgical patients with PIVSDs and VAs. The combination of Euroscore II with a new variable "Nongraftable CALs" significantly improves the performance of the model.
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Affiliation(s)
- Andrei M Belyaev
- Department of Surgical Treatment of Ischemic Heart Disease, Bakoulev's National Medical Research Centre for Cardiac Surgery, Moscow, Russia
| | - Ivan I Skopin
- Department of Surgical Treatment of Ischemic Heart Disease, Bakoulev's National Medical Research Centre for Cardiac Surgery, Moscow, Russia
| | - Galina V Lobacheva
- Intensive Care Unit, Department of Anesthesia and Intensive Care Medicine, Bakoulev's National Medical Research Centre for Cardiac Surgery, Moscow, Russia
| | - Mikhail D Alshibaya
- Department of Surgical Treatment of Ischemic Heart Disease, Bakoulev's National Medical Research Centre for Cardiac Surgery, Moscow, Russia
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2
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Park H, Kim HS, Hong YJ, Min JJ, Kim HB, Kim MC, Sim DS, Kim JH, Kim DY, Lee JS, Ahn Y, Jeong MH. Therapeutic Effect of Fimasartan in a Rat Model of Myocardial Infarction Evaluated by Cardiac Positron Emission Tomography with [ 18F]FPTP. Chonnam Med J 2019; 55:109-115. [PMID: 31161123 PMCID: PMC6536431 DOI: 10.4068/cmj.2019.55.2.109] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 03/13/2019] [Accepted: 04/02/2019] [Indexed: 11/06/2022] Open
Abstract
We evaluated the efficacy of fimasartan on perfusion defects and infarction size in an animal model of myocardial infarction (MI), with echocardiography and positron emission tomography (PET) using a 18F-labeled phosphonium cation (5-[18F]-fluoropentyl-triphenylphosphonium salt, [18F]FPTP) as a mitochondrial voltage sensor for myocardial imaging. We induced MI in 33 rats by ligation of the left coronary artery, and checked their cardiac PET image using [18F]FPTP for evaluation of myocardial perfusion. Rats were grouped into 3 groups according to their administered drugs: no drug (n=11), fimasartan 3 mg/kg (n=10), and fimasartan 10 mg/kg (n=12). Each designated drug was administered for 4 weeks, and follow-up PET and histologic examinations were done. In the PET analysis, a perfusion defect size was markedly improved in fimasartan 10 mg/kg group (35.9±7.0% to 28.4±6.9%, p<0.001), whereas treatment with fimasartan 3 mg/kg induced only an insignificant reduction of perfusion defect size (35.9±7.9% to 33.9±7.3%, p=0.095). Using 2, 3, 5-triphenyltetrazolium chloride staining, infarction size was the largest in the control group (36.5±8.3%), and was insignificantly lower in the fimasartan 3 mg/kg group (31.5±6.5%, p for the difference between the control group=0.146) and was significantly lower in the fimasartan 10 mg/kg group (26.3±7.6%, p for the difference between the control group=0.011). PET imaging using a 18F-labeled mitochondrial voltage sensor, [18F]FPTP, is useful in evaluation and monitoring of myocardial perfusion states, and treatment with fimasartan decreases the infarction size in animal MI model.
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Affiliation(s)
- Hyukjin Park
- Division of Cardiology, Chonnam National University Hospital, Gwangju, Korea
| | - Hyeon Sik Kim
- Institute for Biomedical Science, Chonnam National University Hwasun Hospital, Hwasun, Korea
| | - Young Joon Hong
- Division of Cardiology, Chonnam National University Hospital, Gwangju, Korea
| | - Jung-Joon Min
- Department of Nuclear Medicine, Chonnam National University Hwasun Hospital, Hwasun, Korea
| | - Han Byul Kim
- Division of Cardiology, Chonnam National University Hospital, Gwangju, Korea
| | - Min Chul Kim
- Division of Cardiology, Chonnam National University Hospital, Gwangju, Korea
| | - Doo Sun Sim
- Division of Cardiology, Chonnam National University Hospital, Gwangju, Korea
| | - Ju Han Kim
- Division of Cardiology, Chonnam National University Hospital, Gwangju, Korea
| | - Dong-Yeon Kim
- Department of Nuclear Medicine, Chonnam National University Hwasun Hospital, Hwasun, Korea
| | - Jae Sung Lee
- Department of Nuclear Medicine, Seoul National University Hospital, Seoul, Korea
| | - Youngkeun Ahn
- Division of Cardiology, Chonnam National University Hospital, Gwangju, Korea
| | - Myung Ho Jeong
- Division of Cardiology, Chonnam National University Hospital, Gwangju, Korea
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Abstract
PURPOSE OF REVIEW Hibernation is an important and reversible cause of myocardial dysfunction in ischaemic heart failure. RECENT FINDINGS Hibernation is an adaptive process that promotes myocyte survival over maintaining contractile function. It is innate to mammalian physiology, sharing features with physiological hibernation in other species. Advanced imaging methods have reasonable accuracy in identifying hibernating myocardium. Novel superior hybrid methods may provide diagnostic potential. New evidence supports the role of surgical revascularisation in ischaemic heart failure, but the role of viability tests in planning such procedures remains unclear. Research to date has exclusively involved patients with ambulatory heart failure: Investigating the role of hibernation in ADHF is a key avenue for the future. Whilst our understanding of hibernation pathophysiology has improved dramatically, the clinical utility of identifying and targeting hibernation remains unclear.
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Affiliation(s)
- Matthew J Ryan
- The Rayne Institute, St Thomas' Hospital, 4th Floor Lambeth Wing, Westminster Bridge Road, London, SE1 7EH, UK
| | - Divaka Perera
- The Rayne Institute, St Thomas' Hospital, 4th Floor Lambeth Wing, Westminster Bridge Road, London, SE1 7EH, UK.
- Cardiovascular Division, King's College London, London, UK.
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4
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Schwarz ER, Gupta R, Diep TP, Nowak B, Kostin S, Grohmann B, Uretsky BF, Schaper J. Carvedilol Improves Myocardial Contractility Compared With Metoprolol in Patients With Chronic Hibernating Myocardium After Revascularization. J Cardiovasc Pharmacol Ther 2016; 10:181-90. [PMID: 16211207 DOI: 10.1177/107424840501000306] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Background: We tested the hypothesis of whether carvedilol delays morphologic degeneration and improves functional outcome compared with metoprolol tartrate in patients with hibernating myocardium undergoing surgical revascularization. We have previously shown that patients with chronic hibernating myocardium undergo progressive cellular degeneration and fibrosis. Methods: Twenty patients with multivessel coronary artery disease revascularization and hibernating myocardium as assessed by technetium-99m perfusion scintigraphy and fluorine-18-fluorodeoxyglucose positron emission tomography were randomized to receive either carvedilol or metoprolol tartrate for at least 2 months before surgery, and this was continued for 7 months postoperatively. Left ventricular ejection fraction and regional wall motion abnormalities were assessed by left ventriculography at baseline and 7 months postoperatively. Intraoperative transmural needle biopsy samples were obtained for microscopic analysis. Results: Postoperatively, the ejection fraction increased from 31% ± 5% to 44% ± 4% ( P < .005) in the carvedilol group (n = 10), and from 30% ± 6% to 40% ± 6% in the metoprolol tartrate group ( P < .05 vs preoperatively and vs carvedilol). Wall motion abnormalities in the carvedilol group improved from -2.1 ± 0.4 to -0.6 ± 0.5 ( P < .05) and from -2.3 ± 0.5 to -1.6 ± 0.6 in the metoprolol tartrate group ( P < .05 vs preoperatively and vs carvedilol). Microscopic analysis after 72 ± 18 days of either treatment showed mild cardiomyocyte degeneration and moderate-to-severe fibrosis (28% ± 7%) in the carvedilol group compared with moderate cardiomyocyte degeneration and moderate-to-severe fibrosis (33% ± 6%) in the metoprolol tartrate group. Apoptosis, as assessed by the terminal deoxynucleotidyl transferase nick end labeling method, was observed in only 1 patient in each group. Conclusions: Carvedilol treatment of hibernating myocardium results in improved functional recovery after revascularization compared with metoprolol tartrate, and this might partially be related to reduced cardiomyocyte degeneration.
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Affiliation(s)
- Ernst R Schwarz
- Division of Cardiology, Department of Medicine, University of Texas Medical Branch, Galveston, TX 77555-0553, USA.
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Patel HC, Ellis SG. Role of revascularization to improve left ventricular function. Heart Fail Clin 2015; 11:203-14. [PMID: 25834970 DOI: 10.1016/j.hfc.2014.12.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Coronary revascularization to improve left ventricular (LV) function and improve mortality in patients with ischemic cardiomyopathy remains controversial, especially in the absence of angina or ischemia. A large body of observational evidence suggests that patients with dysfunctional but viable myocardium may experience improvement in mortality and LV function after revascularization. However, results of randomized trials conducted in the last decade dispute the value of viability testing or coronary revascularization in improving outcomes of patients with ischemic cardiomyopathy. However, because of the numerous methodological limitations of these studies, clinical equipoise persists regarding the role of coronary revascularization in certain patients.
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Affiliation(s)
- Harsh C Patel
- Department of Cardiovascular Medicine, The Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, OH 44195, USA
| | - Stephen G Ellis
- Department of Cardiovascular Medicine, The Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, OH 44195, USA.
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6
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Prediction of long-term reverse left ventricular remodeling after revascularization or medical treatment in patients with ischemic cardiomyopathy: a comparative study between SPECT and MRI. Int J Cardiovasc Imaging 2010; 27:343-53. [PMID: 20725789 DOI: 10.1007/s10554-010-9677-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2010] [Accepted: 07/24/2010] [Indexed: 10/19/2022]
Abstract
Patients with ischemic heart disease and depressed left ventricular (LV) ejection fraction (LVEF) develop varying degrees of LV remodeling after cardiac surgical revascularization. Fifty-three patients with stable ischemic heart disease and impaired LV function (LVEF 34.9 ± 4%) were prospectively followed up for 24 months. Thirty-seven patients underwent coronary artery bypass grafting (CABG), 16 patients were treated conservatively. Cardiac magnetic resonance imaging (MRI) and SPECT were performed at baseline and after 12 and 24 months of follow-up. The patients were divided into responders and non-responders depending on the degree of LVEF improvement at 24 months follow-up (>5%-responders). MRI with ≤5 segments with DE/wall thickness ratio (DEWTR) ≥50% predicted LV reverse remodeling with a sensitivity of 86% and a specificity of 75% (AUC 0.81). An MRI finding of ≤2 segments with the DEWTR ≥75% had a corresponding sensitivity of 71% and specificity of 67% (AUC 0.75) while fixed perfusion defect on SPECT <16.5% of LV predicted reverse remodeling with a sensitivity of 64% and a specificity of 69% (AUC 0.64). A preoperative number of segments with the DE/wall thickness ratio of ≥50 and ≥75% obtained by MRI, was found to be a better predictor of left ventricular reverse remodeling than fixed perfusion defect by SPECT. No other MRI or SPECT parameter predicted LVEF improvement at 24 months after CABG.
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7
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Patel RN, Arteaga RB, Mandawat MK, Thornton JW, Robinson VJB. Pharmacologic Stress Myocardial Perfusion Imaging. South Med J 2007; 100:1006-14; quiz 1004. [PMID: 17943047 DOI: 10.1097/smj.0b013e318153f9c6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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8
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Wu YW, Tadamura E, Kanao S, Yamamuro M, Marui A, Komeda M, Toma M, Kimura T, Togashi K. Myocardial viability by contrast-enhanced cardiovascular magnetic resonance in patients with coronary artery disease: comparison with gated single-photon emission tomography and FDG position emission tomography. Int J Cardiovasc Imaging 2007; 23:757-65. [PMID: 17364219 DOI: 10.1007/s10554-007-9215-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2006] [Accepted: 02/14/2007] [Indexed: 12/16/2022]
Abstract
BACKGROUND The aim of this study was to assess the value of contrast-enhanced cardiovascular magnetic resonance (CMR) in viability for patients with coronary artery disease and left ventricular (LV) dysfunction (ejection fraction [EF] </=50%), comparing to gated thallium-201 ((201)Tl) single photon emission computed tomography (SPECT) and (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET). METHODS AND RESULTS One hundred sixteen patients (EF 37.8 +/- 16.2%) underwent stress-reinjection or rest-redistribution gated-SPECT and CMR (46 FDG-PET) within 1 month. All images were analyzed in a 17-segment and 0-4 scales system. Of 1972 segments, delayed enhancement (DE) on CMR correlated well with (201)Tl reduction (r = 0.90, p < 0.0001). The agreement of SPECT (>/=50% maximal (201)Tl activity) and CMR (</=50% DE) was 96.8% (kappa = 0.62). CMR detected more subendocardial scars in 18 subjects (60 segments). Reduced (201)Tl activity but none DE were observed in 19 subjects (76 segments; more inferior) who had lower EF and larger end-systolic volume (p < 0.05). Of 411 dysfunctional segments from 46 patients, FDG-PET (>/=50% of maximal FDG uptake) detected more viability (9%). CONCLUSION The extent of DE correlated (201)Tl activity well. CMR could detect more small infarcts, while FDG-PET could detect more viability. CMR could distinguish between artifacts or infarction on SPECT, especially in poor LV function.
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Affiliation(s)
- Yen-Wen Wu
- Department of Diagnostic Imaging, Kyoto University Graduate School of Medicine, 54 Shogoinkawahara, Sakyo-ku, Kyoto, 606-8507, Japan
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9
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Arrighi JA, Dilsizian V. Assessment of myocardial viability by radionuclide and echocardiographic techniques: is it simply a sensitivity and specificity issue? Curr Opin Cardiol 2006; 21:450-6. [PMID: 16900007 DOI: 10.1097/01.hco.0000240581.89805.4d] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE OF REVIEW The assessment of myocardial viability provides important information that may guide therapeutic decisions in patients with coronary artery disease and left ventricular dysfunction. This review describes methods for assessing myocardial viability using single-photon emission computed tomography, with an emphasis on how to optimize the detection of viable myocardium using current techniques. Relevant comparisons of radionuclide techniques with echocardiographic methods are also discussed. RECENT FINDINGS The basis for the assessment of myocardial viability using radionuclides is reviewed briefly. Radionuclide techniques provide important prognostic information that may affect the decision on if patients with coronary artery disease should be revascularized or treated medically. Data suggest that dobutamine stress echocardiography may underestimate viability in certain patients. Radionuclide techniques that assess both radiotracer uptake and ventricular function can provide a comprehensive approach to detect viable myocardium in most patients. SUMMARY The methods for assessing myocardial viability using single-photon emission computed tomography are accurate, reproducible, and widely available. Viability testing should be considered in patients with known coronary artery disease and left ventricular dysfunction. Further studies are warranted to assess the affect of viability assessment on clinical outcomes.
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Affiliation(s)
- James A Arrighi
- Department of Medicine and Diagnostic Imaging, Brown Medical School, Providence, Rhode Island, USA.
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10
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Abstract
Delayed-enhancement magnetic resonance imaging is a viability imaging technique that has been demonstrated in both animal and patient studies to accurately identify and characterize the presence and transmural extent of myocardial scarring. The precise information regarding the presence, location and extent of myocardial scarring has been shown to be useful in predicting the likelihood of functional recovery of dysfunctional myocardium after revascularization. Perhaps, more importantly, the ability to visualize the extent of viable and nonviable myocardium across the ventricular wall allows one to approach viability as a continuum rather than in a binary manner, providing a better reflection of the underlying physiology.
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Affiliation(s)
- Michael D Elliott
- Duke Cardiovascular Magnetic Resonance Center, Division of Cardiology, Duke University, Durham, North Carolina 27710, USA.
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11
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Yamakawa Y, Takahashi N, Ishikawa T, Uchino K, Mochida Y, Ebina T, Kobayashi T, Matsushita K, Matsumoto K, Kawasaki N, Shimura M, Ohkusu Y, Sumita S, Kimura K, Inoue T, Umemura S. Clinical usefulness of ECG-gated 18F-FDG PET combined with 99mTC-MIBI gated SPECT for evaluating myocardial viability and function. Ann Nucl Med 2005; 18:375-83. [PMID: 15462399 DOI: 10.1007/bf02984480] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
OBJECTIVES This study sought to evaluate an imaging approach using gated 99mTc-MIBI (MIBI) SPECT and gated 18F-FDG (FDG) PET for assessment of myocardial viability and cardiac function. METHODS Forty-eight patients (38 men, mean age 68.1 +/- 9.6 years) underwent ECG-gated FDG PET and MIBI SPECT within a week. The baseline diagnoses were coronary artery disease (31), mitral regurgitation (1), paroxysmal arrhythmia (10), and dilated cardiomyopathy (6). The gated FDG PET data were analyzed using pFAST software, and the gated MIBI SPECT data were analyzed using QGS software. Fifteen patients were diagnosed with myocardial infarction, and follow-up study was performed to assess the functional outcome four months later. An improvement in LVEF of >5% was defined as significant. The LV myocardium was divided into 17 segments, and regional defect scores were visually assessed using a 4-point scale for each segment (0 = normal, 1 = mildly reduced, 2 = moderately reduced, 3 = absent). A segment with a greater defect score on MIBI SPECT than on FDG PET was defined as a mismatch. The patients were divided into two groups: those with at least two mismatched segments (MM-group), and those with none or one (M-group). RESULTS LVEF, EDV and ESV measured by gated FDG PET were highly correlated with those obtained by gated MIBI SPECT (r = 0.848, 0.855 and 0.911, p < 0.0001, respectively). The mean values of LVEF did not differ significantly, but EDV and ESV obtained by gated FDG PET were significantly grater than those obtained by gated MIBI SPECT (p < 0.0001). In 15 patients diagnosed with myocardial infarction, a significant association (p < 0.05) was found between the relative uptake of FDG PET and MIBI SPECT and the functional outcome 4 months later. Global LV function improved in 6 of the 8 patients showing mismatch but in only 1 of the 7 patients with matched defects, resulting in a sensitivity of 86% and specificity of 75%. The overall accuracy to predict global functional outcome was high (80%). CONCLUSION This imaging approach allows accurate evaluation of myocardial viability. Furthermore, the high correlations of gated FDG PET and gated MIBI SPECT measurements hold promise for the assessment of left ventricular function using gated FDG PET.
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Affiliation(s)
- Yohei Yamakawa
- Second Department of Internal Medicine, Yokohama City University School of Medicine, 3-9 Fukuura, Yokohama 236-0004, JAPAN.
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12
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Yao SS, Chaudhry FA. Assessment of Myocardial Viability with Dobutamine Stress Echocardiography in Patients with Ischemic Left Ventricular Dysfunction. Echocardiography 2005; 22:71-83. [PMID: 15660693 DOI: 10.1111/j.0742-2822.2005.04030.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The noninvasive assessment of myocardial viability has proved clinically useful for distinguishing hibernating and/or stunned myocardium from irreversibly injured myocardium in patients with chronic ischemic heart disease or recent myocardial infarction, with marked regional and/or global left ventricular (LV) dysfunction. Noninvasive techniques utilized for the detection of viability in asynergic myocardial regions include positron emission tomographic imaging of residual metabolic activity, single photon emission tomography (SPECT) of radioisotope uptake with thallium-201, low-dose dobutamine echocardiography assessment of inotropic reserve and myocardial contrast echocardiography for evaluation of microvascular integrity. Of these techniques, dobutamine stress echocardiography is a safe, widely available and relatively inexpensive modality for the identification of myocardial viability for risk stratification and prognosis. Low-dose dobutamine response can accurately predict improvement of dysfunctional yet viable myocardial regions, and thus identify a subset of patients whose LV function will improve following successful coronary revascularization.
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Affiliation(s)
- Siu-Sun Yao
- Division of Cardiology, Department of Medicine, St. Luke's Roosevelt Hospital Center, Columbia University College of Physicians and Surgeons, New York, NY 10025, USA
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Bourque JM, Velazquez EJ, Borges-Neto S, Shaw LK, Whellan DJ, O'connor CM. Clinical characteristics and referral pattern of patients with left ventricular dysfunction and significant coronary artery disease undergoing radionuclide imaging. J Nucl Cardiol 2004; 11:118-25. [PMID: 15052242 DOI: 10.1016/j.nuclcard.2003.09.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Many observational studies that predict patient outcomes have examined the use of myocardial perfusion imaging results. However, a referral pattern for radionuclide testing could bias these analyses and should be determined. These patients may also differ with regard to the extent of coronary artery disease (CAD). All of these differences must be incorporated into proper outcomes examinations. We sought to identify the nuclear perfusion imaging referral pattern for patients with left ventricular (LV) dysfunction and significant CAD. METHODS AND RESULTS Patients with LV dysfunction and CAD (n = 2951) meeting our inclusion criteria were compared by receipt or absence of radionuclide perfusion testing within 6 months before or after angiography. Pearson chi2 and Kruskal-Wallis analyses were used to examine differences in baseline characteristics and catheterization results, whereas logistic regression modeling was applied to predict nuclear imaging referral before and after catheterization. Precatheterization nuclear cohort patients were more likely to be minority patients (odds ratio [OR], 1.34; P =.0083) with previous cardiac revascularization (OR, 2.27; P =.0001), Charlson comorbidity index greater than 1 (OR, 1.146; P =.0091), and heart failure symptoms (OR, 1.62; P =.0001) than those without imaging. They were less likely to have a myocardial infarction (OR, 0.464; P =.0001). After catheterization, the nuclear patients were more likely to have had congestive heart failure (OR, 1.452; P =.0019), a myocardial infarction (OR, 1.353; P =.0371), an ejection fraction lower than 30% (OR, 1.058; P =.0002), and prior revascularization (OR, 1.880; P =.0001). In addition, they had fewer diseased vessels (OR, 0.731; P =.0001). CONCLUSIONS Bias exists in nuclear referral for patients with LV dysfunction and significant CAD and must be considered when interpreting observational studies on this topic.
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Affiliation(s)
- Jamieson M Bourque
- Division of Cardiology, Department of Internal Medicine, Duke University Medical Center, Durham, NC 27710, USA.
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Palmieri V, Okin PM, Bella JN, Gerdts E, Wachtell K, Gardin J, Papademetriou V, Nieminen MS, Dahlöf B, Devereux RB. Echocardiographic wall motion abnormalities in hypertensive patients with electrocardiographic left ventricular hypertrophy: the LIFE Study. Hypertension 2003; 41:75-82. [PMID: 12511533 DOI: 10.1161/01.hyp.0000045081.54784.36] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
There is limited information on correlates of left ventricular wall motion (WM) abnormalities in ambulatory patients with hypertension and ECG left ventricular hypertrophy by Cornell voltage-duration product and/or Sokolow-Lyon voltage criteria. Therefore, we assessed the prevalence and the correlates of echocardiographic global and segmental left ventricular WM abnormalities in 942 hypertensive patients with hypertrophy enrolled in the Losartan Intervention For End-point reduction in hypertension (LIFE) echo substudy. Patients were separated into groups of those with normal WM or those with segmental or global WM abnormalities. Segmental and global WM abnormalities were mostly of mild degree and were detected in 7% and 6% of the study sample. Compared with subjects with normal motion, those with WM abnormalities were mostly men and had higher prevalences of self-reported coronary heart disease, ECG signs of myocardial infarction, ST-strain pattern, and higher Cornell voltage-duration product, echo-left ventricular mass, and albuminuria, but lower total and high-density lipoprotein cholesterol. Blood pressure was similar among groups. No significant differences were found between patients with global or segmental WM abnormalities. Only half of patients with WM abnormalities had a history or ECG signs of coronary heart disease. Independent correlates of WM abnormalities were higher albuminuria and Cornell voltage-duration product, male gender, and echo-left ventricular hypertrophy, but lower cholesterol. In a subanalysis restricted to patients with WM abnormalities, those with evident cardiovascular disease had a higher prevalence of ST-strain pattern than those with subclinical WM abnormalities, but other clinical, ECG, or echocardiographic parameters were indistinguishable between the 2 groups. Thus, in hypertensives with ECG left ventricular hypertrophy, WM abnormalities, mostly of mild degree, occurred in one eighth of the patients and were associated with male gender, left ventricular hypertrophy, and albuminuria. No significant differences were found between patients with global or segmental wall motion abnormalities.
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15
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Wagdy HM, Christian TF, Miller TD, Gibbons RJ. The value of 24-hour images after rest thallium injection. Nucl Med Commun 2002; 23:629-37. [PMID: 12089485 DOI: 10.1097/00006231-200207000-00007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Rest (201) Tl imaging has been used for detecting viability, but the ideal timing for imaging after injection to maximally estimate viability is not well established. Thirty patients with fixed or incompletely reversible defects on 4 h redistribution SPECT imaging after thallium rest injection underwent 24 h imaging. Global redistribution was subjectively rated none, minimal or meaningful by two experienced observers. Fourteen patients had no meaningful redistribution at either 4 h or 24 h. Ten patients had meaningful redistribution at 4 h only. Six patients had no meaningful redistribution at 4 h but did at 24 h. Defect size was quantified using a 70% threshold. For the total group, defect size was smaller at 4 h compared to immediate imaging (38+/-18% vs 41+/-19%, P=0.06) and smaller still at 24 h (36+/-16% vs 38+/-18%, P=0.02). Later (24 h) redistribution images detected additional redistribution in 30% of the patients who did not have meaningful redistribution on early (4 h) images, and in 8% of the segments which were abnormal at 4 h. It is concluded that, in patients who have incompletely reversible defects on early redistribution imaging at 4 h, late redistribution imaging after 24 h will demonstrate additional redistribution in 30% of the patients.
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Affiliation(s)
- H M Wagdy
- Division of Cardiovascular Diseases and Internal Medicine, Mayo Clinic, Rochester, Minnesota 55905, USA
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Peral V, Vilacosta I, Fernández C, Hernández M, San Román JA, Batlle E, Meroño E, Carreras JL, Bethencourt A. [Comparison of dobutamine echocardiography and rest-redistribution 201-thallium SPECT in the assessment of myocardial viability taking PET as gold standard]. Rev Esp Cardiol 2001; 54:1394-405. [PMID: 11754785 DOI: 10.1016/s0300-8932(01)76522-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
BACKGROUND AND AIM To compare Tl-201 SPECT and dobutamine stress echocardiography for the detection of myocardial viability in patients with severe left ventricular dysfunction using metabolic imaging by positron emission tomography as the standard reference. MATERIAL AND METHODS We studied 25 consecutive patients with severe coronary artery disease and left ventricular dysfunction that underwent two different diagnostic modalities for evaluating myocardial viability: stress echocardiography with incremental doses of dobutamine from 5 up to 40 g/kg/min in 3 min stages, and 201 Tl SPECT using a rest-redistribution protocol with delayed images obtained at 4 hours. Fluorodeoxyglucose uptake by PET was used as the gold standard. Viability criteria were as follows, for 201Tl SPECT imaging: normal uptake at rest and presence of redistribution in the delayed images, for dobutamine stress echocardiography: sustained improvement and biphasic response. RESULTS Sensitivity of thallium redistribution was 46%, for normal uptake, plus redistribution 82%, 34% for dobutamine biphasic response and 58% for sustained improvement plus biphasic response. Specificity of biphasic response was 82% and that of redistribution 67%. Stepwise logistic regression indicated that biphasic wall motion response during dobutamine stress echocardiography (2.01 CI 95%; 1.10 to 3.99) and the presence of redistribution plus normal uptake at rest with thallium imaging (2.68 CI 95%; 1.42 to 5.13) were the best predictors of viability. These results were the same when both techniques were analyzed together. CONCLUSIONS Biphasic wall motion response during dobutamine stress echocardiography and the normal uptake plus presence of redistribution with thallium imaging were the best pre
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Affiliation(s)
- V Peral
- Hospital Universitario Son Dureta.Palma de Mallorca, Spain
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Choi KM, Kim RJ, Gubernikoff G, Vargas JD, Parker M, Judd RM. Transmural extent of acute myocardial infarction predicts long-term improvement in contractile function. Circulation 2001; 104:1101-7. [PMID: 11535563 DOI: 10.1161/hc3501.096798] [Citation(s) in RCA: 399] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
BACKGROUND Previous animal studies have demonstrated that the transmural extent of acute myocardial infarction defined by contrast-enhanced MRI (ceMRI) relates to early restoration of flow and future improvements in contractile function. We tested the hypothesis that ceMRI would have similar predictive value in humans. METHODS AND RESULTS Twenty-four patients who presented with their first myocardial infarction and were successfully revascularized underwent cine and ceMRI of their heart within 7 days (scan 1) of the peak MB band of creatine kinase. Cine MRI was repeated 8 to 12 weeks later (scan 2). The transmural extent of infarction on scan 1 and wall thickening on both scans were determined using a 72-segment model. A total of 524 of 1571 segments (33%) were dysfunctional on scan 1. Improvement in segmental contractile function on scan 2 was inversely related to the transmural extent of infarction on scan 1 (P=0.001). Improvement in global contractile function, as assessed by ejection fraction and mean wall thickening score, was not predicted by peak creatine kinase-MB (P=0.66) or by total infarct size, as defined by MRI (P=0.70). The best predictor of global improvement was the extent of dysfunctional myocardium that was not infarcted or had infarction comprising <25% of left ventricular wall thickness (P<0.005 for ejection fraction, P<0.001 for mean wall thickening score). CONCLUSION In patients with acute myocardial infarction, the transmural extent of infarction defined by ceMRI predicts improvement in contractile function.
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Affiliation(s)
- K M Choi
- Feinberg Cardiovascular Research Institute, Department of Medicine, Northwestern University Medical School, Chicago, Illinois, USA
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Peral V, Vilacosta I, de la Peña A, San Román JA, Fernández C, Hernández M, Batlle E, Carreras JL, Bethencourt A. [Thallium-201 scintigraphy and dobutamine echocardiography in the assessment of myocardial viability]. Rev Clin Esp 2001; 201:5-15. [PMID: 11293986 DOI: 10.1016/s0014-2565(01)70732-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND The possibility of differentiating viable from non-viable tissue among patients with severe coronary artery disease and severe left ventricular impairment entails relevant clinical and therapeutic implications since it may influence the indication of patient revascularization. To evaluate the presence of myocardial viability two techniques are available in the clinical setting: echocardiography with intravenous infusion of dobutamine and scintigraphy with myocardial perfusion with thalliem-201 by means of single-photon emission tomography. OBJECTIVE To compare prospectively the value of these techniques for detecting viable myocardium. MATERIAL AND METHODS Thirty-five patients with severe coronary disease and severe left ventricular dysfunction were included in the study. All patients underwent an echocardiogram using incremental doses of dobutamine, from 5 up to 40 micrograms/kg/min in three-minute periods. For thallium-201 scintigraphy the rest redistribution protocol with delayed images at 4 hours was used. The criteria for detecting viability were: a) for thallium-201, the presence of redistribution in delayed images and normal uptake at rest, and b) for dobutamine echocardiography, a sustained improvement in regional motion, biphasic response, and worsening. RESULTS By considering the segmental improvement post-revascularization as "gold standard" of viability, the statistically significant variables in a logistic regression model and, therefore, predictors of segmental functional recovery were the biphasic response and the sustained response for dobutamine echocardiography and normal uptake at rest and redistribution in the delayed images for thallium-201. Taken together, the result was significant for the biphasic response of dobutamine echocardiography. CONCLUSIONS The biphasic response with dobutamine echocardiography is the echocardiographic pattern that best predicts the functional recovery of the ischemic myocardium. A normal uptake and redistribution at four hours is the only scintigraphic pattern that can predict functional improvement. Of both patterns, the biphasic response is the best predictor of the functional recovery of the dysfunctional myocardium.
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Affiliation(s)
- V Peral
- Servicio de Cardiología, Hospital Universitario Son Dureta, C./Andrea Doria, 55, 07014 Palma de Mallorca
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Altinmakas S, Dagdeviren B, Uyan C, Keser N, Gümüş V, Pektaş O. Prediction of viability by pulsed-wave Doppler tissue sampling of asynergic myocardium during low-dose dobutamine challenge. Int J Cardiol 2000; 74:107-13. [PMID: 10962109 DOI: 10.1016/s0167-5273(00)00226-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Dobutamine stress echocardiography is widely used to predict reversible left ventricular dysfunction, but evaluation with this method is subjective. Pulsed-wave tissue Doppler imaging is a new technique that allows to obtain quantitative data on wall motion velocities of different myocardial segments through sample-volume placement. Therefore, this tool in combination with DSE may be suitable for identifying viability in asynergic myocardium. To evaluate this, in 40 patients (mean age 57+/-9) with resting dyssynergy (akinesis in 52, hypokinesis in 30) baseline wall motion scores and tissue Doppler variables were collected before and after 5 min infusion of 10 microg/kg per min dobutamine. Forty-six of 82 segments were classified as viable (a reduction in segmental score of at least one grade) according to follow-up echocardiography that was performed 4 weeks after revascularization. While myocardial S velocity percent increase in viable segments was 45+/-10, the increase was 25+/-12 in necrotic segments (n=36) during 10 microg dobutamine infusion (P=0.0001). Assuming 35% as a cut-off for viability the increase in S velocities by DSE yielded an 89% sensitivity and 86% specificity for predicting post-revascularization functional recovery. In conclusion, pulsed-wave tissue Doppler imaging of asynergic myocardium during dobutamine stress echocardiography can identify the viability quantitatively.
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Affiliation(s)
- S Altinmakas
- Cardiology Department, Maltepe University, Istanbul, Turkey.
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Fitzgerald J, Parker JA, Danias PG. F-18 fluoro deoxyglucose SPECT for assessment of myocardial viability. J Nucl Cardiol 2000; 7:382-7. [PMID: 10958281 DOI: 10.1067/mnc.2000.107821] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Identification of myocardial viability in hypokinetic segments is important in patients with ischemic cardiomyopathy because systolic dysfunction improves with revascularization. Positron emission tomography (PET) F-18 fluoro deoxyglucose (FDG) uptake has been demonstrated as an accurate indicator of metabolically active and thus viable myocardium. F-18 FDG single photon emission computed tomography (SPECT) has recently been introduced and offers a technically easier and less costly alternative to PET imaging for determination of myocardial viability. A body of literature demonstrates that F-18 FDG SPECT can reliably be performed with SPECT hardware equipped with 511-keV collimators, which provides an accurate assessment of myocardial viability. F-18 FDG SPECT offers data similar to those offered by F-18 FDG PET and compares favorably with other imaging modalities, including rest-redistribution and stress-reinjection thallium-201 myocardial perfusion imaging, gated technetium 99m SPECT, and low-dose dobutamine echocardiography.
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Affiliation(s)
- J Fitzgerald
- Department of Radiology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Mass, USA
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Chen C, Liu J, Hua D, Ma L, Lai T, Fallon JT, Knibbs D, Gillam L, Mangion J, Knight DR, Waters D. Impact of delayed reperfusion of myocardial hibernation on myocardial ultrastructure and function and their recoveries after reperfusion in a pig model of myocardial hibernation. Cardiovasc Pathol 2000; 9:67-84. [PMID: 10867357 DOI: 10.1016/s1054-8807(00)00029-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
UNLABELLED This study examined the effect of delayed reperfusion of myocardial hibernation from 24 hours to 7 days on myocardial ultrastructural and functional changes and their recoveries after reperfusion. BACKGROUND We have previously shown in pigs that after reperfusion the functional and structural alterations in short-term myocardial hibernation which was reperfused in 24 hours can recover in 7 days. The effect of delayed reperfusion of hibernating myocardium on the extent and severity of cellular and extracellular structural changes of hibernating myocardium, and their recoveries after reperfusion is not known. METHODS AND RESULTS A severe LAD stenosis was created in 27 pigs, reducing resting flow by 30-40% immediately after placement of the stenosis and producing acute ischemia as evidenced by regional lactate production, a decrease in regional coronary venous pH, reduced regional wall thickening (from 38.5 +/- 5.1% to 10.4 +/- 8.0%) and a 33% reduction of regional oxygen consumption. The stenosis was maintained either for 24 hours in 9 pigs (group 1) with LAD flow of 0.65 +/- 0.13 ml/min/g (38% reduction), or for 7 days in 17 pigs (group 2) with LAD flow of 0.67 +/- 0.14 ml/min/g (36% reduction). There were no differences (p = NS) in the reduction of wall thickening, rate-pressure product, lactate production, or regional oxygen consumption between group 1 and group 2. Quantitative morphometric evaluation of the ultrastructure on electromicrographs revealed a greater decrease in sarcomere volume and a higher incidence of myocytes with reduced sarcomere volume in 7-day than in 24-hour hibernating regions (53 +/- 19% versus 33 +/- 14%, p < 0.05). Patchy myocardial necrosis with replacement fibrosis was common, but 6 of the 18 pigs had no myocardial necrosis or replacement fibrosis in the 7-day hibernating group, and 4 of 9 pigs had no patchy myocyte necrosis in the 24 hour hibernating group. In 6 pigs in group 1 in which the stenosis was then released and hibernating myocardium reperfused in 24 hours, regional wall thickening recovered to 30 +/- 6% (p = NS compared to baseline) after one week of reperfusion. In 12 pigs in group 2 in which the stenosis was released and hibernating myocardium reperfused in 7 days, regional wall thickening recovered slowly, from 10.1 +/- 7.2% to 18.1 +/- 8.3% at one week (n = 5) and to 28.0 +/- 3.6% at 3-4 weeks of reperfusion (n = 7, p < 0.05 compared to baseline). Similarly, the sarcomere volume or myofilament recovered significantly (p < 0.01) and was not different compared to the normal region (p = NS) in the 24-hour hibernating region of group 1, but the recovery was much slower and was incomplete at 4 weeks (p < 0.01) compared to baseline in the 7-day hibernating region of group 2. Recovery of regional wall thickening correlated with ultrstructural recovery (p < 0.01). By multivariate stepwise regression analysis, the degree of LAD flow reduction, the extent of fibrosis, and myofilament loss were independent predictors of the extent of functional recovery. CONCLUSIONS In a porcine model of myocardial hibernation with myocardial hypoperfusion, systolic dysfunction, and metabolic adaptations, a longer period of myocardial hibernation with delayed reperfusion was associated with more severe abnormalities of myocytes. an increasing interstitial fibrosis, and more protracted myofibrillar and functional recoveries after reperfusion. The extent of functional recovery is related to the degree of coronary flow reduction, the severity of the ultrastructural changes, and the extent of interstitial fibrosis.
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Affiliation(s)
- C Chen
- Division of Cardiology, Hartford Hospital, Hartford, CT, USA.
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Haque T, Furukawa T, Takahashi M, Maeda K, Kinoshita M. Myocardial viability detected by dobutamine echocardiography in patients with chronic coronary artery disease, and long-term outcome after coronary angioplasty. JAPANESE CIRCULATION JOURNAL 2000; 64:183-90. [PMID: 10732849 DOI: 10.1253/jcj.64.183] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Viable but dysfunctional myocardium detected by dobutamine echocardiography (DE) predicts early improvement in regional left ventricular (LV) function after percutaneous transluminal coronary angioplasty (PTCA). Whether DE can predict the long-term (>2 years) outcome after PTCA is still unclear. Thus, 50 patients (age 60.4+/-9.5 years) with chronic coronary artery disease and regional LV dysfunction who underwent DE 1 week before PTCA to assess myocardial viability were followed for 4.0+/-0.8 years. Regional LV function and LV ejection fraction (LVEF) were evaluated by 2-dimensional echocardiography in patients who remained event-free (cardiac death or myocardial infarction or unstable angina pectoris) after PTCA. At late follow-up (>2 years after PTCA), 29 patients showed regional LV function improvement, 15 showed no improvement, 3 showed worsening and 3 patients had cardiac events (1 nonfatal myocardial infarction and 2 unstable angina pectoris). LVEF improved (0.53+/-0.09 to 0.60+/-0.09, p<0.001) in patients with improved regional LV function, but deteriorated (0.38+/-0.03 to 0.30+/-0.03) in the 3 patients with worsened regional LV function. Of the 29 patients with improvement, 27 (93%) had viable myocardium, whereas only 3 (20%) of the 15 with no improvement had viable myocardium and all 6 of those with poor outcomes (3 with cardiac events and 3 with worsening) had viable myocardium (chi2 = 28.9, p<0.001). Patients with viable myocardium and a poor outcome had a lower mean LVEF before PTCA, and at 1 week and 3 months after PTCA (p = 0.004, <0.001, and =0.001, respectively), and a higher restenosis rate (p = 0.007) than patients with viable myocardium and without a poor outcome. It is concluded that viable myocardium detected by DE may predict long-term improvement in regional and global LV function after PTCA. However, patients with viable myocardium and persistent low LVEF are at risk for cardiac events or worsening of LV function.
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Affiliation(s)
- T Haque
- The First Department of Internal Medicine, Shiga University of Medical Science, Japan
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Schwarz ER, Reffelmann T, Schoendube F, Hermanns B, Chakupurakal R, Doerge H, Schuetz T, Foresti M, Messmer BJ, Radke PW, Hanrath P. Hypoxic Hypoperfusion Fails to Induce Myocardial Hibernation in Anesthetized Swine. J Cardiovasc Pharmacol Ther 1999; 4:235-247. [PMID: 10684545 DOI: 10.1177/107424849900400405] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND: Congenital origin of the left coronary artery from the pulmonary artery (ALCAPA) results in chronically dysfunctional myocardium with the partial ability to recover after revascularization. We attempted to establish an ALCAPA syndrome in anesthetized pigs for 24 hours and to compare it with stunned and infarcted myocardium. METHODS AND RESULTS: In group 1 (n = 12), a bypass graft was interposed between the pulmonary artery and the left anterior descending coronary artery (LAD). Reduction of flow in the LAD with gradual increases in flow from the pulmonary artery resulted in an incremental reduction of segment shortening (8.9 +/- 5.3% at 24 hours vs 26.6 +/- 10% at baseline, P <.005). In group 3 (n = 5), 2 cycles of 10-minute LAD occlusion resulted in decreased segment shortening with slow recovery (at 24 hours 18.7 +/- 1.3% vs 24.2 +/- 4% at baseline, segment shortening with slow recovery (at 24 hours 18.7 +/- 1.3% vs 24.2 +/- 4% at baseline, P <.05). In group 3 (n = 6), 1-hour LAD occlusion reduced segment shortening at 24 hours to 4.7 +/- 5.2% (P <.005 vs baseline). Histological analysis of the LAD territory revealed severe degeneration, myolysis, and alteration of the chromatin structure in group 1 comparable to ischemic cell death in group 3, whereas control areas and the LAD area in group 2 showed only minor structural alterations. Infarct size/risk area, as measured by tetrazolium staining, was 49.8 +/- 11.2% in group 1, 9.3 +/- 8.1% in group 2 (P <.005), and 60.3 +/- 9% in group 3. CONCLUSION: Hypoxic myocardial hypoperfusion from the pulmonary artery results in myocardial necrosis in anesthetized pigs. These findings are in contrast to the concept of myocardial hibernation in the ALCAPA syndrome because in this model, hypoxic hypoperfusion failed to induce adaptation to preserve myocardial structure.
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Affiliation(s)
- ER Schwarz
- Medical Clinic I, Institute of Pathology, Germany
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Chaudhry FA, Tauke JT, Alessandrini RS, Vardi G, Parker MA, Bonow RO. Prognostic implications of myocardial contractile reserve in patients with coronary artery disease and left ventricular dysfunction. J Am Coll Cardiol 1999; 34:730-8. [PMID: 10483954 DOI: 10.1016/s0735-1097(99)00252-1] [Citation(s) in RCA: 125] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
OBJECTIVES This study was performed to assess the prognostic implications of myocardial contractile reserve (MCR) in patients with coronary artery disease (CAD) and left ventricular (LV) dysfunction. BACKGROUND MCR during dobutamine stress echocardiography (DSE) identifies viable myocardium that may improve in function after revascularization. Whether revascularization influences prognosis of patients with MCR has not been determined. METHODS We performed DSE in 80 patients with CAD and LV dysfunction (ejection fraction < or =40%). Viable myocardium was defined in dysfunctional myocardial segments as enhanced thickening and contraction during low-dose dobutamine (5 to 10 mcg/kg/min). Serial prospective follow-up was obtained in all patients (mean follow-up 2.2 +/- 1.1 years). RESULTS Among 52 patients treated medically, there were 20 cardiac deaths. By multivariate analysis, the number of dysfunctional segments demonstrating MCR was the strongest predictor of survival (p < 0.03). Patients with MCR had better initial survival during medical therapy than did those without MCR, but this survival advantage was not maintained beyond three years. In contrast, survival was excellent in patients with MCR who underwent myocardial revascularization. Among 58 patients with MCR in > or =5 myocardial segments, survival at three years was 93 +/- 6% in the 24 patients who were revascularized but only 49 +/- 15% in the 34 treated medically (p < 0.02). CONCLUSIONS Myocardial contractile reserve is a significant predictor of survival in patients with CAD and LV dysfunction undergoing medical therapy. Although patients with MCR have an initial survival advantage, this advantage is lost over the course of three years. In contrast, survival in patients with significant MCR is enhanced by revascularization.
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Affiliation(s)
- F A Chaudhry
- Division of Cardiology and the Feinberg Cardiovascular Research Institute, Northwestern University Medical School, Chicago, Illinois, USA
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Sias TM, Watson DD, Beller GA. Is nitroglycerin useful for the enhancement of viability detection with myocardial perfusion imaging? Am Heart J 1999; 138:206-9. [PMID: 10426830 DOI: 10.1016/s0002-8703(99)70103-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Oudiz RJ, Smith DE, Pollak AJ, Mena I, Shapiro SM, Ginzton LE, Narahara KA. Nitrate-enhanced thallium 201 single-photon emission computed tomography imaging in hibernating myocardium. Am Heart J 1999; 138:369-75. [PMID: 10426854 DOI: 10.1016/s0002-8703(99)70127-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVES This study tested the usefulness of nitrate-enhanced thallium 201 imaging for detecting myocardial viability. BACKGROUND Previous work suggests that nitrates enhance the ability of (201)Tl imaging to detect viable myocardium. METHODS Eighteen patients with coronary artery disease underwent (201)Tl imaging at rest, after 4 hours of redistribution, and during intravenous nitroglycerine infusion (mean dose = 5.96 +/- 5.37 microgram/kg/min). Twelve patients had their echocardiograms repeated after revascularization. Perfusion and wall motion were scored from 0 to 2 (absent to normal). RESULTS All the regions identified as viable by the rest/redistribution pair of scans were identified as viable by the rest/nitroglycerine pair of scans. Ninety-one percent of these regions were identified as viable by the single nitroglycerine scan alone. In patients who underwent revascularization, the total (201)Tl perfusion score improved from 193 to 214 after revascularization (P =.009). Wall motion score improved from 151 to 168 after revascularization (P =.09). Both the rest/nitroglycerine and rest/redistribution studies correctly predicted 14 (88%) of 16 regions that improved after revascularization. Most importantly, the rest/nitroglycerine and rest/redistribution studies were able to predict postrevascularization myocardial viability (absence of akinesis or dyskinesis after revascularization), with a sensitivity of 95% and 92%, respectively, and a predictive accuracy of 84.4%. CONCLUSIONS Nitroglycerine infusion during (201)Tl imaging is a useful technique for detecting underperfused, viable myocardium, requires less time to perform than rest/redistribution imaging, and may allow detection of viable myocardium with a single (201)Tl single-photon emission computed tomographic study.
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Affiliation(s)
- R J Oudiz
- Saint John's Cardiovascular Research Center, Department of Medicine, Torrance, CA 90509, USA.
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Kitsiou AN, Srinivasan G, Quyyumi AA, Summers RM, Bacharach SL, Dilsizian V. Stress-induced reversible and mild-to-moderate irreversible thallium defects: are they equally accurate for predicting recovery of regional left ventricular function after revascularization? Circulation 1998; 98:501-8. [PMID: 9714106 DOI: 10.1161/01.cir.98.6.501] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND In patients with coronary artery disease, stress-redistribution-reinjection thallium scintigraphy provides important information regarding myocardial ischemia and viability. Although both reversible and mild-to-moderate irreversible thallium defects retain metabolically active, viable myocardium, we hypothesized that stress-induced reversible thallium defects may better differentiate reversible from irreversible regional left ventricular dysfunction after revascularization. METHODS AND RESULTS Twenty-four patients with chronic coronary artery disease underwent prerevascularization and postrevascularization exercise-redistribution-reinjection thallium single photon emission CT, gated MRI, and radionuclide angiography. After revascularization, mean left ventricular ejection fraction increased from 30+/-9% to 37+/-13% at rest (P<0.001). Before revascularization, abnormal contraction at rest was observed in 56 of 110 reversible and 20 of 37 mild-to-moderate irreversible thallium defects (51% and 54%, respectively). After revascularization, regional contraction improved in 44 of 56 reversible compared with 6 of 20 mild-to-moderate irreversible thallium defects (79% and 30%, respectively; P<0.001). The final thallium content (maximum tracer uptake on redistribution-reinjection images) was significantly higher in regions with reversible defects that improved than in those that did not improve after revascularization (86+/-16% versus 66+/-9%, P<0.001). In contrast, final thallium content was similar in regions with mild-to-moderate irreversible defects that improved and in those that did not improve after revascularization (69+/-9% versus 65+/-10%, P=NS). Furthermore, when asynergic regions were grouped according to the final thallium content, at 60% threshold value, functional recovery was observed in 83% of regions with reversible defects compared with 33% of regions with mild-to-moderate irreversible defects (P<0.001). CONCLUSIONS These findings suggest that although both reversible and mild-to-moderate irreversible thallium defects after stress retain viable myocardium, the identification of reversible thallium defect on stress in an asynergic region more accurately predicts recovery of function after revascularization. Even at a similar mass of viable myocardial tissue (as reflected by the final thallium content), the presence of inducible ischemia is associated with an increased likelihood of functional recovery.
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Affiliation(s)
- A N Kitsiou
- Cardiology Branch, National Heart, Lung, and Blood Institute, and the Department of Nuclear Medicine, National Institutes of Health, Bethesda, MD 20892, USA
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Hirata N, Sakai K, Ohtani M, Sakaki S, Ohnishi K, Miyamoto Y, Nakano S, Matsuda H. Efficacy of coronary artery bypass grafting in patients with a dilated left ventricle due to myocardial infarction. JAPANESE CIRCULATION JOURNAL 1998; 62:565-70. [PMID: 9741732 DOI: 10.1253/jcj.62.565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
This study was designed to clarify the efficacy of coronary artery bypass grafting (CABG) on left ventricular (LV) function in 16 patients with a dilated LV due to myocardial infarction (LV end-systolic volume index: LVESVI >60 ml/m2). All had attained complete revascularization. To estimate the LV wall motion quantitatively using echocardiography, a wall motion score (WMS) was used (LV was divided into 17 segments with a four-point scale: akinesis=3, severe hypokinesis=2, hypokinesis=1, normal=0 and then summed). Exercise stress tests were performed after surgery, revealing that anginal symptoms had vanished in all the patients. In 5 patients with a preoperative end-systolic volume index (ESVI) >100 ml/m2, the ejection fraction (EF) did not change, and both were under 30% (before to after: 26+/-4 to 26+/-4%). Neither the ESVI (148+/-50 to 133+/-39 ml/m2) nor the end-diastolic volume index (end-diastolic volume index (EDVI): 198+/-62 to 180+/-37 ml/m2) changed; the WMS did not change (33+/-2 to 33+/-3). During exercise, in spite of the increase in heart rate (HR) (at rest, 81+/-20; HR during exercise, 111+/-21 beats/min, p<0.005) and LV end-diastolic pressure (EDP) (22+/-9; 35+/-13 mmHg, p<0.02), both cardiac index (CI) (2.4+/-0.3; 2.6+/-0.4 L/min x m2) and minute work (MW: 4.0+/-1.1; 4.1+/-0.4 kg x M/min) did not increase. In 11 patients with a preoperative ESVI <100 ml/m2, EF was extremely increased in 5 patients (more than 10%, 35+/-4 to 60+/-6%, p<0.005=improved subgroup) in whom the EDVI (130+/-16 to 120+/-13 ml/m2) did not change whereas the ESVI (82+/-14 to 48+/-7 ml/m2) was reduced. However, in the 6 remaining patients (ie nonimproved subgroup), neither ESVI (78+/-8 to 74+/-12 ml/m2), EDVI (115+/-10 to 115+/-20 ml/m2) nor EF (31+/-7 to 35+/-3%) changed. During exercise, HR (at rest, 88+/-13; during exercise, 108+/-11 beats/min, p<0.005), LVEDP (20+/-6; 29+/-7 mmHg, p<0.01), CI (2.5+/-0.6; 3.3+/-0.5 L/min x m2, p<0.05), MW (4.6+/-1.0; 6.5+/-1.5 kg x M/min, p<0.05) increased. The WMS in the nonimproved subgroup did not change (29+/-6 to 27+/-2), but in the improved subgroup it reduced after surgery (27+/-3 to 19+/-4, p<0.01). These data suggested that CABG in patients with a dilated LV was effective against anginal symptoms, but was restricted to left ventricular function. It may be possible to estimate postoperative LV function, including exercise tolerance, from the preoperative LVESVI.
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Affiliation(s)
- N Hirata
- Division of Cardiac Surgery, Sakurabashi Watanabe Hospital, Osaka, Japan
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31
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Petretta M, Cuocolo A, Nicolai E, Acampa W, Salvatore M, Bonaduce D. Combined assessment of left ventricular function and rest-redistribution regional myocardial thallium-201 activity for prognostic evaluation of patients with chronic coronary artery disease and left ventricular dysfunction. J Nucl Cardiol 1998; 5:378-86. [PMID: 9715982 DOI: 10.1016/s1071-3581(98)90143-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
BACKGROUND This study evaluated the prognostic value of combined assessment of left ventricular (LV) function and regional myocardial thallium activity in patients with nonrecent myocardial infarction and LV dysfunction. METHODS AND RESULTS Eighty-two patients with previous myocardial infarction (>8 weeks) and echocardiographic evidence of LV dysfunction underwent thallium-201 rest-redistribution tomography and cardiac catheterization. During the follow-up period (mean 25 months) there were 18 cardiac events (14 deaths and 4 nonfatal myocardial infarctions). Multivariate Cox regression analysis on clinical, angiographic, and thallium variables showed that the number of echocardiographic dysfunctional segments with preserved thallium uptake (> or =50% of peak activity; chi-square 11.03; p<0.005) and age (chi-square 8.12, p<0.01) were predictive of poor outcome. At incremental analysis, combined echocardiographic and thallium data provided significant additional information to clinical, thallium, and LV functional data, increasing global chi-square value from 22.4 to 31.5 (p< 0.01). Similarly, combined data gave additional information after considering clinical, echocardiographic, and LV functional data, increasing global chi-square from 17.8 to 22.3 (p <0.05). Differently, the number of diseased vessels at coronary angiography did not add further prognostic information. CONCLUSIONS In patients with previous myocardial infarction and chronic LV dysfunction, the combination of echocardiographic and thallium rest-redistribution imaging data gives prognostic information incremental to those of clinical and LV functional data and to those of each technique considered separately.
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Affiliation(s)
- M Petretta
- Institute of Internal Medicine, Cardiology and Heart Surgery, Nuclear Medicine Center of the National Council of Research (CNR), Department of Biomorphological and Functional Sciences, University Federico II, Naples, Italy
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32
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Anselmi M, Golia G, Cicoira M, Tinto M, Nitti MT, Trappolin R, Rossi A, Zanolla L, Marino P, Zardini P. Prognostic value of detection of myocardial viability using low-dose dobutamine echocardiography in infarcted patients. Am J Cardiol 1998; 81:21G-28G. [PMID: 9662223 DOI: 10.1016/s0002-9149(98)00049-6] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Revascularization can improve ventricular function in patients with viable myocardium, but whether and how the presence of viable myocardium affects prognosis of infarcted patients is still far from clear. Thus, 202 patients (173 men, 59 +/- 9 years old) with a previous or recent myocardial infarction (MI) and regional asynergies underwent low-dose dobutamine echocardiography (5-15 microg/kg per min) to assess myocardial viability and were followed for a period of 16 +/- 11 months after revascularization (89 patients) or medical therapy (113 patients). Four groups of patients were defined: (1) patients with viability, revascularized (n = 64); (2) patients with viability, treated medically (n = 52); (3) patients without viability, revascularized (n = 25); and (4) patients without viability, treated medically (n = 61). Of these patients, 45 (23%) patients suffered 57 cardiac events: 18 cardiac deaths (9%), 7 MIs, 12 unstable angina, 9 heart failures, and 11 new revascularization procedures. Patients with viability, revascularized, experienced a slightly lower event rate (22%) compared with patients with viability, treated medically, patients without viability, treated medically and patients without viability, revascularized (29%, 31%, and 36%, respectively; p = not significant [NS]). The frequency of events was then evaluated in those 108 patients with an ejection fraction < or =33%, in whom 14 cardiac deaths occurred: the incidence of cardiac death was slightly lower in patients with viability, revascularized (3/37, 8%) than in the patients with viability, treated medically (4/26, 15%), patients without viability, revascularized (2/11, 18%), or patients without viability, treated medically (5/34, 15%) (p = NS). Nonfatal cardiac events were significantly fewer (p <0.05) in patients with viability, revascularized (8%) and in patients without viability, treated medically (6%) than in patients with viability, treated medically and patients without viability, revascularized (27%). In infarcted patients with severe left ventricular dysfunction, the presence of viable myocardium, if left unrevascularized, leads to further events. On the contrary, in the absence of myocardial viability, revascularization could lead to a worse prognosis than medical therapy.
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Affiliation(s)
- M Anselmi
- Division of Cardiology, University of Verona, Italy
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Kloner RA, Bolli R, Marban E, Reinlib L, Braunwald E. Medical and cellular implications of stunning, hibernation, and preconditioning: an NHLBI workshop. Circulation 1998; 97:1848-67. [PMID: 9603540 DOI: 10.1161/01.cir.97.18.1848] [Citation(s) in RCA: 291] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- R A Kloner
- Heart Institute, Good Samaritan Hospital, and University of Southern California, Los Angeles 90017, USA
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34
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Schwarz ER, Schoendube FA, Kostin S, Schmiedtke N, Schulz G, Buell U, Messmer BJ, Morrison J, Hanrath P, vom Dahl J. Prolonged myocardial hibernation exacerbates cardiomyocyte degeneration and impairs recovery of function after revascularization. J Am Coll Cardiol 1998; 31:1018-26. [PMID: 9562002 DOI: 10.1016/s0735-1097(98)00041-2] [Citation(s) in RCA: 97] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVES We sought to define the effects of time on contractile function, morphology and functional recovery after coronary revascularization in patients with dysfunctional but viable (hibernating) myocardium. BACKGROUND Functional recovery after coronary artery bypass graft surgery in patients with chronic myocardial hibernation is incomplete or delayed. The proposed cause is a progressive temporal degeneration of cardiomyocytes. METHODS In 32 patients with multivessel coronary disease, regional wall motion analysis was performed in hypoperfused but metabolically active areas before and 6 months after bypass surgery. During bypass surgery, transmural biopsy samples were obtained from the center of the hypokinetic zone for light and electron microscopic analyses. The proposed duration of myocardial hibernation was retrospectively assessed. RESULTS Patients with a subacute hibernating condition (<50 days) demonstrated a higher preoperative ejection fraction (EF, 50+/-8%), and a better preserved wall motion (WM) in the supraapical wall (-1.4+/-0.4) than did patients with intermediate-term (>50 days, EF 37+/-9%, p < 0.05; WM -2.4+/-1.5, p = 0.08) or chronic (>6 months, EF 40+/-14%, WM -2.7+/-0.9, p < 0.005) ischemia. Structural degeneration correlated with the duration of ischemia (r = 0.56, p < 0.05). Postoperative recovery of function was enhanced in patients with a short history of hibernation compared with patients with an intermediate-term or chronic condition (EF 60+/-10% vs. 40+/-10%, p < 0.001, and vs. 47+/-14%, p < 0.05). CONCLUSIONS Hibernating myocardium exhibits time-dependent deterioration due to progressive structural degeneration with enhanced fibrosis. Early revascularization should be attempted to salvage the jeopardized tissue and improve postoperative outcome.
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Affiliation(s)
- E R Schwarz
- Department of Cardiology, Medical Clinic I, Rheinisch-Westfälsche Technische Hochschule University Hospital Aachen, Germany.
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35
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Beckmann S, Bocksch W, Müller C, Schartl M. Does dobutamine stress echocardiography induce damage during viability diagnosis of patients with chronic regional dysfunction after myocardial infarction? J Am Soc Echocardiogr 1998; 11:181-7. [PMID: 9517557 DOI: 10.1016/s0894-7317(98)70075-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Experimental hibernating-model investigations of animals have shown that myocardial necrosis can be induced by longer-term intracoronary dobutamine infusion. This study was designed to determine whether myocardial infarction could be ascertained in patients with chronic regional wall motion abnormalities and greater than 75% stenosis in the supplying coronary artery through dobutamine stress echocardiography. Twenty patients with coronary artery disease and regional resting wall motion abnormalities were examined with a standard dobutamine protocol (5 to 50 microg/kg/min). Exclusion criteria were an acute coronary syndrome, severe heart failure, and severe hypertension. Creatine kinase (CK, CKMB), myoglobin, and troponine-I were measured before and at each of the first 7 hours after beginning of infusion. Fourteen of these 20 patients exhibited viable myocardium. The serum markers CK, CKMB, myoglobin, and troponin-I demonstrated no increase beyond the reference range, suggesting that with this protocol, no myocardial necrosis was induced.
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Affiliation(s)
- S Beckmann
- Department of Cardiology, Virchow Clinic and German Heart Institute Berlin
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36
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Koh TW, Pepper JR, Gibson DG. Early changes in left ventricular anterior wall dynamics and coordination after coronary artery surgery. HEART (BRITISH CARDIAC SOCIETY) 1997; 78:291-7. [PMID: 9391293 PMCID: PMC484933 DOI: 10.1136/hrt.78.3.291] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
OBJECTIVE To study how asynchronous left ventricular wall motion changes early after uncomplicated coronary artery surgery. DESIGN A prospective study done before, and at 0.5, 1, and 3 hours after coronary artery grafting, with intraoperative transoesophageal cross sectional guided M mode echocardiograms, high fidelity left ventricular pressure, and thermodilution cardiac output measurements. The extent and velocity of left ventricular anterior wall thickening were measured, along with regional work and power production. Abnormal thickness changes during the isovolumic periods were detected, and their effect on energy transfer quantified as cycle efficiency. SETTING Tertiary referral cardiac centre. PATIENTS 25 patients with a history of chronic stable angina, mean (SD) age 60 (9) years with three vessel coronary artery disease, undergoing uncomplicated coronary artery bypass grafting. RESULTS 4 patients had primary incoordination, as shown by wall thinning during isovolumic contraction and delayed onset of thickening (group A), and nine had premature thickening due to incoordination elsewhere (group B). The extent (thickening fraction 43 (12)% v 73 (19)%) and velocity (1.7 (0.4) v 2.5 (0.6) cm/s) of thickening were reduced in group A v group B (P < 0.001), as were regional stroke work (2.2 (0.8) v 3.3 (0.4) mJ/cm2) and peak power production (19 (5) v 32 (7) mW/cm2), P < 0.05. In group A, these values all increased significantly within 30 minutes of operation. In group B, the extent of wall thickening and peak power production were unaffected by surgery, though cycle efficiency and regional stroke work both improved by 30 minutes v before operation (73 (9)% v 61 (8)%, 4.5 (0.9) v 3.3 (0.4) mJ/cm2, P < 0.01). Surgery had no consistent effect on left ventricular cavity size, shortening fraction, or cardiac output in either group. CONCLUSIONS Even in the absence of evidence of overt ischaemia, major disturbances of ventricular synchrony--both regional and generalised--are present in patients with a history of chronic stable angina requiring coronary artery bypass grafting. They regress within 30 minutes of revascularisation, suggesting that they are the direct result of coronary stenosis.
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Affiliation(s)
- T W Koh
- Cardiac Department, Royal Brompton Hospital, London SW3, United Kingdom
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37
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Petretta M, Cuocolo A, Bonaduce D, Nicolai E, Vicario ML, Salvatore M. Prognostic value of coronary angiography in patients with chronic ischemic left ventricular dysfunction and evidence of viable myocardium on thallium reinjection imaging. J Nucl Cardiol 1997; 4:387-95. [PMID: 9362015 DOI: 10.1016/s1071-3581(97)90030-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND We evaluated the independent and incremental prognostic value of cardiac catheterization and coronary angiographic data over thallium reinjection after stress redistribution imaging in patients with myocardial infarction and left ventricular dysfunction. METHODS AND RESULTS Sixty-nine patients with a first myocardial infarction (> 8 weeks) and left ventricular ejection fraction < or = 40% underwent thallium-201 reinjection after stress redistribution tomographic imaging and cardiac catheterization. During follow-up (mean 26 months) 11 cardiac events (8 cardiac deaths and 3 nonfatal myocardial infarctions) occurred. On Cox regression analysis independent predictors of cardiac events were the sum of reversible and moderately irreversible defects at thallium reinjection (chi 2, 16.4, p < 0.005) and the number of reversible defects at stress redistribution (chi 2, 5.1, p < 0.05). Moreover, thallium reinjection imaging improved the prognostic power of clinical, exercise, and stress redistribution data (p < 0.01). The inclusion of left ventricular ejection fraction produced a borderline improvement (p = 0.06), whereas the number of vessels with coronary disease did not. In contrast, in patients at high risk such as those with at least 25% of viable myocardium at reinjection, the number of diseased vessels provided additional prognostic information (p < 0.05). CONCLUSIONS In patients with chronic ischemic left ventricular dysfunction, left ventricular ejection fraction, but not the number of diseased vessels, provides additional prognostic information to thallium imaging. Therefore coronary angiography seems unnecessary in these patients, unless a significative amount of viable myocardium is detectable.
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Affiliation(s)
- M Petretta
- Institute of Internal Medicine, Cardiology, and Heart Surgery, National Research Council, Napoli, Italy
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38
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Abstract
The identification of viable myocardium in the setting of acute myocardial infarction or chronic coronary artery disease with reduced left ventricular function has important prognostic and therapeutic implications. Many noninvasive methods have been used to assess viability, and recently, dobutamine stress echocardiography has been studied for this purpose. Dobutamine stress echocardiography is a safe, accessible, and relatively inexpensive technique. Moreover, its accuracy for detecting viability approaches that of positron emission tomography and thallium scintigraphy. In addition to dobutamine stress echocardiography, other echocardiographic techniques, such as myocardial contrast echocardiography and dipyridamole stress echocardiography, are being developed to delineate viability. In the future, echocardiographic methods may identify viability with enough accuracy to allow us to better select patients for revascularization procedures when the indications are otherwise unclear.
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Affiliation(s)
- J C Lualdi
- Charles A. Dana Research Institute, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA
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39
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Pagley PR, Beller GA, Watson DD, Gimple LW, Ragosta M. Improved outcome after coronary bypass surgery in patients with ischemic cardiomyopathy and residual myocardial viability. Circulation 1997; 96:793-800. [PMID: 9264484 DOI: 10.1161/01.cir.96.3.793] [Citation(s) in RCA: 273] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND Although residual myocardial viability in patients with coronary artery disease and extensive regional asynergy is associated with improved ventricular function after coronary bypass surgery, the relationship between viability and clinical outcome after surgery is unclear. We hypothesized that patients with poor ventricular function and predominantly viable myocardium have a better outcome after bypass surgery compared with those with less viability. METHODS AND RESULTS Seventy patients with multivessel coronary artery disease and left ventricular ejection fractions < 40% who underwent preoperative quantitative 201Tl scintigraphy before coronary bypass surgery were analyzed retrospectively. 201Tl scintigrams were reviewed blindly, and each segment was assigned a score based on defect magnitude. Segmental viability scores were summed and divided by the number of segments visualized to determine a viability index. The viability index was significantly related to 3-year survival free of cardiac event (cardiac death or heart transplant) after bypass surgery (P=.011) and was independent of age, ejection fraction, and number of diseased coronary vessels. Patients with greater viability (group 1; viability index > 0.67; n=33) were similar to patients with less viability (group 2; viability index < or = 0.67; n=37) with respect to age, comorbidities, and extent of coronary artery disease. There were 6 cardiac deaths and no heart transplants in group 1 patients and 15 cardiac deaths and two transplants in group 2 patients. Survival free of cardiac death or transplantation was significantly better in group 1 patients on Kaplan-Meier analysis (P=.018). CONCLUSIONS We conclude that resting 201Tl scintigraphy may be useful in preoperative risk stratification for identification of patients more likely to benefit from surgical revascularization.
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Affiliation(s)
- P R Pagley
- Department of Internal Medicine, University of Virginia Health Sciences Center, Charlottesville 22908, USA
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40
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Khoury AF, Rivera JM, Mahmarian JJ, Verani MS. Adenosine thallium-201 tomography in evaluation of graft patency late after coronary artery bypass graft surgery. J Am Coll Cardiol 1997; 29:1290-5. [PMID: 9137226 DOI: 10.1016/s0735-1097(97)00045-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVES We sought to ascertain the utility of adenosine thallium-201 tomography for assessing graft stenoses late after coronary artery bypass graft surgery. BACKGROUND Although pharmacologic perfusion imaging has been increasingly used in the assessment of patients with coronary artery disease, the value of this stress modality for detecting coronary artery bypass graft stenosis late after surgery is unknown. METHODS We studied 109 patients who underwent both adenosine thallium-201 tomography and coronary angiography at 6.7 +/- 4.8 (mean +/- SD) years after coronary artery bypass graft surgery. Adenosine thallium-201 tomography was assessed quantitatively by computer-generated polar maps of the myocardial thallium-201 activity. RESULTS On coronary angiography, significant graft stenoses were present in 68 patients, 65 of whom had a corresponding perfusion defect as shown by thallium-201 tomography (sensitivity 96%). Significant stenoses were present in 107 (37.8%) of 283 grafts. The overall specificity by quantitative tomography was 61%. Seventy percent of the apparently false positive perfusion defects could be explained on the basis of unbypassed native disease or by the presence of fixed defects in patients with previous myocardial infarction. CONCLUSIONS Thus, results of adenosine thallium-201 tomography are nearly always abnormal in patients with late coronary graft stenosis. Most of the false positive defects appear to be due to either unbypassed native disease or a previous myocardial infarction.
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Affiliation(s)
- A F Khoury
- Department of Internal Medicine, Baylor College of Medicine, Houston, Texas, USA
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41
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Barrabés Riu JA, García-Dorado D, Alonso Martín J, Coma Canella I, Valle Tudela V. [Role of noninvasive examinations in the management of ischemic heart disease. III. Assessment of myocardial viability]. Rev Esp Cardiol 1997; 50:75-82. [PMID: 9092006 DOI: 10.1016/s0300-8932(97)73183-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Assessment of myocardial viability is a field of growing interest. This article summarizes the pathophysiology of myocardial stunning and hibernation; both phenomena are associated with the presence of dysfunctional, viable myocardium. The techniques that are currently available for the assessment of viability, and the clinical situations in which these assessments may be more useful are discussed.
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Affiliation(s)
- J A Barrabés Riu
- Servicio de Cardiología, Hospital General Universitari Vall d'Hebron, Barcelona
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42
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Gürsürer M, Pinarli AE, Aksoy M, Tosun R, Yeşilçimen K, Ersek B. Assessment of viable myocardium and prediction of postoperative improvement in left ventricular function in patients with severe left ventricular dysfunction by quantitative planar stress-redistribution-reinjection 201-T1 imaging. Int J Cardiol 1997; 58:179-84. [PMID: 9049684 DOI: 10.1016/s0167-5273(96)02859-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
A noninvasive approach to determine viable but asynergic myocardium will be clinically significant in identifying patients with coronary artery disease and severe left ventricular dysfunction who will benefit most from coronary bypass surgery. Accordingly, 12 patients (mean ejection fraction 0.32 +/- 0.03) underwent quantitative planar stress-redistribution-reinjection thallium scintigraphy and radionuclide ventriculography before and 8 weeks after revascularization for viability and segmental and global left ventricular function assessment, respectively. Reinjection scan showed new fill-in in 63% of segments without redistribution. Postoperative improvement in perfusion and function of asynergic segments were significantly better in viable compared to nonviable segments (P < 0.001, P < 0.01, respectively) with a strong correlation between improvement in 201-T1 uptake and function (P < 0.001). When adequacy of revascularization was considered, the predictive value of a positive preoperative viability test for functional improvement was 83%. Finally, mean ejection fraction and global wall motion score increased significantly after revascularization for the group as a whole (0.32 +/- 0.03 to 0.44 +/- 0.04, P < 0.001 and 24.08 +/- 2.90 to 33.16 +/- 3.32, P < 0.001, respectively). Thus, preoperative quantitative planar stress-redistribution-reinjection thallium imaging detects viable but asynergic segments which improve function postoperatively and may be valuable in selection of patients with severe left ventricular dysfunction for revascularization.
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Affiliation(s)
- M Gürsürer
- Prof. Dr. Siyami Ersek Thoracic and Cardiovascular Surgery Center, Istanbul, Turkey
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43
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State-of-the-Art Diagnosis in Myocardial Ischema. Vasc Med 1997. [DOI: 10.1007/978-94-009-0037-0_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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44
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45
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Kostopoulos KG, Kranidis AI, Bouki KP, Antonellis JP, Kappos KG, Rodogianni FE, Zamanis NJ, Tavernarakis AG, Lolas CT, Anthopoulos LP. Detection of myocardial viability in the prediction of improvement in left ventricular function after successful coronary revascularization by using the dobutamine stress echocardiography and quantitative SPECT rest-redistribution-reinjection 201TI imaging after dipyridamole infusion. Angiology 1996; 47:1039-46. [PMID: 8921752 DOI: 10.1177/000331979604701103] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The aim of this study was to assess the feasibility, safety, and respective diagnostic accuracy of low-dose dobutamine infusion and rest-redistribution-reinjection thallium 201 single photon emission computed tomography (SPECT) after dipyridamole infusion (Th-DIP), in the prediction of functional improvement of asynergic infarcted zones, after successful revascularization in patients with chronic ischemic heart disease. Thirty-one patients with a previous myocardial infarction and left ventricular dysfunction (mean ejection fraction: 41 +/- 5.8%) were studied. The regional wall motion of the left ventricle was evaluated by basic echocardiography before and 14 +/- 1.7 weeks after successful revascularization (19 by percutaneous transluminal coronary angioplasty and 12 by coronary artery bypass grafting). Dobutamine stress echocardiography (DSE) was performed in all patients with dobutamine infusion of 5 and 10 micrograms/kg/minute over five minutes. Within three days after DSE and prior to revascularization, all patients underwent Th-DIP for myocardial viability assessment. A 16-ventricular-segment model was used for basic, DSE, and Th-DIP images. Viability was assessed by applying the standard criteria for each technique. In the 31 patients, 496 segments were analyzed. By basic echocardiography, 164 (33%) of them were classified as asynergic. The DSE detected viable tissue in 69/496 (14%) segments, whereas Th-DIP identified viability in 95/496 (19%) segments. When the postrevascularization basic echocardiographic study was used as the gold standard in identifying myocardial viability, the sensitivity and specificity for the DSE and Th-DIP were 86.5%, 94.4% and 90.5%, 69%, respectively. No major side effects were observed with both techniques. In conclusion, DSE seems to be an accurate method for identifying viable but asynergic myocardium in patients with chronic ischemic heart disease, whereas Th-DIP overestimates the postrevascularization recovery. Detection of hibernating myocardium can be obtained by these two noninvasive methods. However, DSE seems to be more useful in determining the prospective selection of patients who are going to benefit from revascularization.
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Affiliation(s)
- K G Kostopoulos
- First Department of Cardiology, Evangelismos General Hospital, Athens, Greece
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46
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Kranidis A, Bouki T, Kostopoulos K, Kappos K, Sideris A, Antonellis J, Kardaras F, Margaris N, Lolas C, Anthopoulos L. The Contribution of the Left Atrioventricular Plane Displacement During Low Dose Dobutamine Stress Echocardiography in Predicting Recovery of Left Ventricular Dyssynergies. Echocardiography 1996; 13:587-598. [PMID: 11442973 DOI: 10.1111/j.1540-8175.1996.tb00939.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
The aim of this study was to assess the significance of the left systolic atrioventricular (AV) plane displacement during low dose dobutamine stress echocardiography (DSE), in predicting the recovery of left ventricular dyssynergies after revascularization. In 30 infarctiers with left ventricular dysfunction scheduled for RE (14 percutaneous transluminal coronary angioplasty and 16 coronary artery bypass graft) and in 25 age- and sex-matched healthy subjects, a DSE, using a 16 ventricular segment model and a four-grade scoring system for the assessment of regional wall motion of the left ventricle was performed. Prior and during DSE, the left systolic AV plane displacement was recorded from the apical four- and two-chamber views, by M-mode echo, at four left ventricular sites, corresponding to the septal, lateral, anterior, and inferior walls, both in patients and controls. The study was repeated in all patients 101 +/- 14 days after successful revascularization. Healthy subjects showed a significant increase of left systolic AV plane displacement at all left ventricular sites during dobutamine infusion (DI) (P < 0.001). Patients also exhibited a significant maximum increase of left systolic AV plane displacement during DSE only in the dyssynergic sites with functional improvement in the postrevascularization echocardiogram (P < 0.001). In the remaining dyssynergic sites, without functional improvement after revascularization, the left systolic AV plane displacement did not change (P > 0.05). Selecting a maximum LAVPD increase of >2 mm at any site of the left ventricule to predict recovery of the regional ventricular dyssynergies, results in a sensitivity of 91%, specificity of 83%, positive predictive value of 88%, and negative predictive value of 87%. When two-dimensional DSE was used for the detection of reversible dysfunction, sensitivity and specificity were found to be 81.5% and 87.5%, respectively, while the positive and negative predictive values were 90% and 78%, respectively. When the two methods were in agreement the sensitivity was 90%, the specificity 100%, and the positive and negative predictive values were 100% and 84.2%, respectively. The assessment of left systolic AV plane displacement during DI constitutes a new, simple, and accurate method in the prediction of left ventricular dyssynergy recovery after revascularization. The combination of this method and two-dimensional DSE are basic predictor markers of viability of dysfunctional myocardium. (ECHOCARDIOGRAPHY, Volume 13, November 1996)
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Aronson S, Savage R, Fernandez A, Klein A, Young C, Toledano A, Lee BK, Karp RB, Lytle B, Loop F. Assessing myocardial perfusion with Albunex during coronary artery bypass surgery: technical considerations and safety of aortic root injections. J Cardiothorac Vasc Anesth 1996; 10:713-8. [PMID: 8910149 DOI: 10.1016/s1053-0770(96)80195-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE To test the safety and report on limiting technical considerations, including optimal dosing of Albunex (Molecular Biosystems, Inc, Mallinckrodt Medical, St. Louis, MO) for myocardial opacification after intra-aortic root injections during cardiac surgery. DESIGN This was a prospective randomized study with a control group who did not receive Albunex and a group who received intra-aortic root injections of Albunex. SETTING Multicenter (two) independent university hospitals. PARTICIPANTS 32 patients scheduled for elective coronary artery bypass surgery were evaluated after individual informed consent was obtained. INTERVENTIONS 2 to 8 mL of Albunex were injected before and after coronary revascularization. MEASUREMENTS AND MAIN RESULTS Quality of enhancement in each of four regions of the left ventricle was assessed from a short-axis mid-papillary ultrasound image by three experienced observers blinded to dose. Electrocardiogram (ECG), creatine phosphokinase (CPK) (MB fraction), and hemodynamics were evaluated at baseline and throughout the study period for up to 72 hours. No differences were noted between groups with respect to preoperative and postoperative CPK enzymes (CPK-MB fraction), ECG changes, hemodynamics, requirements for separation from CPB, need for postoperative inotropes, time to extubation, and time to discharge from the intensive care unit. The average total dose of Albunex injected was 19 mL +/- 4 (0.25 mL/kg). A single dose of 4.2 +/- 1.2 mL (0.05 mL/kg) appeared to offer optimal enhancement of contrast effect for myocardial perfusion assessment. CONCLUSION Albunex is safe and easy to use for myocardial opacification when administered via an antegrade cardioplegia catheter into the aortic root during CPB.
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Affiliation(s)
- S Aronson
- Department of Anesthesia and Critical Care, University of Chicago, IL 60637, USA
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Hillis GS, Metcalfe MJ. The diagnosis and management of cardiac failure. Scott Med J 1996; 41:72-5. [PMID: 8807701 DOI: 10.1177/003693309604100302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- G S Hillis
- Department of Cardiology, Aberdeen Royal Hospitals NHS Trust, Fosterhill
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Senior R, Glenville B, Basu S, Sridhara BS, Anagnostou E, Stanbridge R, Edmondson SJ, Handler CE, Raftery EB, Lahiri A. Dobutamine echocardiography and thallium-201 imaging predict functional improvement after revascularisation in severe ischaemic left ventricular dysfunction. Heart 1995; 74:358-64. [PMID: 7488446 PMCID: PMC484038 DOI: 10.1136/hrt.74.4.358] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
OBJECTIVES To evaluate the concordance between thallium-201 uptake and echocardiographic wall thickening, which are both indicators of potentially reversible myocardial dysfunction, in patients with chronic ischaemic left ventricular failure and to assess their relative contribution to predicting improvement in regional function after revascularisation in a subgroup. PATIENTS AND METHODS 45 patients with chronic ischaemic left ventricular dysfunction (mean (SD) ejection fraction 25 (8)%) underwent echocardiography before and after dobutamine infusion (10 micrograms/kg/min). Of these, 22 patients underwent rest echocardiography at a mean (SD) of 9 (1) weeks after revascularisation. 201Tl imaging was performed during dobutamine echocardiography and at rest, 1, and 4 h after treatment with sublingual glyceryl trinitrate on two separate days. Potentially reversible dysfunction was thought to be present when a myocardial segment contained a Tl score of > or = 3 (ascending score 1-4), or showed improved wall thickening of a dysynergic segment during dobutamine stimulation. RESULTS Of the 201Tl protocols, the redistribution scan 1 h after treatment with glyceryl trinitrate best demonstrated myocardial viability. Concordance between 201Tl and dobutamine induced wall thickening was 82% (kappa = 0.59) for detecting potentially reversible myocardial dysfunction before revascularisation (n = 45). Regional function improved in 18 of 22 patients after revascularisation. There were 168 dysynergic segments before intervention. The sensitivity of echocardiography and 201Tl imaging for detecting "recoverable" or viable segments after revascularisation was 87% and 92% respectively and specificity was 82% and 78% respectively (P = NS). CONCLUSIONS Dobutamine echocardiography and 201Tl imaging may be used to predict mechanical improvement in dysynergic segments after revascularisation in patients with chronic ischaemic left ventricular dysfunction.
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Affiliation(s)
- R Senior
- Department of Cardiology, Northwick Park Hospital, Harrow, Middlesex
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