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Lu X, Zhao M, Tian C, Wei H, Gao M, Yang X, Zhang X, Li X. Prognostic value of ventricular mechanical dyssynchrony in patients with left ventricular aneurysm: A comparative study of medical and surgical treatment. J Nucl Cardiol 2022; 29:652-660. [PMID: 32909240 DOI: 10.1007/s12350-020-02343-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2020] [Accepted: 08/11/2020] [Indexed: 12/28/2022]
Abstract
BACKGROUND The prognostic value of left ventricular (LV) mechanical dyssynchrony (MD) in patients with LV aneurysm (LVA) is unclear. This study aimed to investigate the long-term prognostic value of LVMD in LVA patients. METHODS 92 consecutive patients who underwent 99mTc-sestamibi-gated SPECT myocardial perfusion imaging (GSPECT) were retrospectively analyzed and followed-up for a median of 63 months (range, 1-73 months). LV function and histogram bandwidth (BW) were analyzed by QGS software. LVMD was defined by ROC analysis. Cardiac death was defined as the primary endpoint, and the composite of cardiac deaths and severe or acute heart failure (MACE) as the secondary endpoint. RESULTS The annual cardiac mortality rate of LVA patients with LVMD and treated by surgical therapy was significantly lower than those treated by medical therapy (2.40% vs. 6.40%, P < .05) but not annual MACE rate (6.61% vs. 10.06%, P > .05). In patients without LVMD, no significant difference in survival and MACE-free survival between medical and surgical treatment. In addition, the occurrence of LVMD is related to the worsen cardiac outcome in terms of MACE and cardiac death, independent of the treatment methods. BW was an independent predictor for MACE (HR 1.010, P < .01) and LVEF (HR .928, P < .05) was an independent predictor for cardiac death in all LVA patients. CONCLUSIONS LVA patients with LVMD might be associated with high risk for cardiac death and surgical treatment might improve cardiac survival compared to medical therapy in these patients.
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Affiliation(s)
- Xia Lu
- Department of Nuclear Medicine, Laboratory for Molecular Imaging, Beijing Anzhen Hospital, Capital Medical University, No. 2, Anzhen Road, Chaoyang District, Beijing, 100029, China
| | - Min Zhao
- Department of Nuclear Medicine, Zibo Central Hospital, Zibo, Shandong Province, China
| | - Congna Tian
- Department of Nuclear Medicine, Hebei General Hospital, Shijiazhuang, Hebei Province, China
| | - Hongxing Wei
- Department of Nuclear Medicine, State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, and National Center for Cardiovascular Disease, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Mingxin Gao
- Department of Cardiac Surgery, Beijing Anzhen Hospital, Capital Medical University, Beijing, China
| | - Xiubin Yang
- Department of Cardiac Surgery, Beijing Anzhen Hospital, Capital Medical University, Beijing, China
| | - Xiaoli Zhang
- Department of Nuclear Medicine, Laboratory for Molecular Imaging, Beijing Anzhen Hospital, Capital Medical University, No. 2, Anzhen Road, Chaoyang District, Beijing, 100029, China.
| | - Xiang Li
- Department of Nuclear Medicine, Laboratory for Molecular Imaging, Beijing Anzhen Hospital, Capital Medical University, No. 2, Anzhen Road, Chaoyang District, Beijing, 100029, China
- Division of Nuclear Medicine, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria
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Zelt JGE, Wang JZ, Mielniczuk LM, Beanlands RSB, Fallavollita JA, Canty JM, deKemp RA. Positron Emission Tomography Imaging of Regional Versus Global Myocardial Sympathetic Activity to Improve Risk Stratification in Patients With Ischemic Cardiomyopathy. Circ Cardiovasc Imaging 2021; 14:e012549. [PMID: 34102857 PMCID: PMC8208501 DOI: 10.1161/circimaging.121.012549] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
BACKGROUND Current risk assessment approaches fail to identify the majority of patients at risk of sudden cardiac arrest (SCA). Noninvasive imaging of the cardiac sympathetic nervous system using single-photon emission computed tomography and positron emission tomography offers the potential for refining SCA risk assessment. While various [11C]meta-hydroxyephedrine quantification parameters have been proposed, it is currently unknown whether regional denervation or global innervation yields greater SCA risk discrimination. The aim of the study was to determine whether the global innervation parameters yield any independent and additive prognostic value over the regional denervation alone. METHODS In a post hoc competing-risks analysis of the PAREPET trial (Prediction of Arrhythmic Events With Positron Emission Tomography), we compared global innervation and regional denervation parameters using the norepinephrine analog [11C]meta-hydroxyephedrine for SCA risk discrimination. Patients with ischemic cardiomyopathy (n=174) eligible for an implantable cardioverter-defibrillator for the primary prevention of SCA were recruited into the trial. [11C]meta-hydroxyephedrine uptake and clearance rates were measured to assess global (left ventricle mean) retention index and volume of distribution. Regional defects were quantified as the percentage of the left ventricle having values <75% of the maximum. RESULTS During a median follow-up of 4.2 years, there were 56 cardiac-related deaths, of which 26 were SCAs. For any given regional denervation volume, there was substantial heterogeneity in global innervation scores. Global retention index and distribution volume did not decrease until regional defects exceeded 40% left ventricle. Global scale parameters, retention index, and distribution volume (area under the curve=0.61, P=0.034, P=0.046, respectively), yielded inferior SCA risk discrimination compared to regional heterogeneity (area under the curve=0.74). CONCLUSIONS Regional denervation volume has superior cause-specific mortality prediction for SCA versus global parameters of sympathetic innervation. These results have widespread implications for future cardiac sympathetic imaging, which will greatly simplify innervation analysis. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01400334.
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Affiliation(s)
- Jason G E Zelt
- Department of Medicine (Cardiology), University of Ottawa Heart Institute, Canada (J.G.E.Z., J.Z.W., L.M.M., R.S.B.B., R.A.dk.)
- Faculty of Medicine (J.G.E.Z., J.Z.W., L.M.M., R.S.B.B., R.A.dk.), University of Ottawa, Canada
- Department of Cellular and Molecular Medicine (J.G.E.Z., L.M.M., R.S.B.B.), University of Ottawa, Canada
| | - Jean Zhuo Wang
- Department of Medicine (Cardiology), University of Ottawa Heart Institute, Canada (J.G.E.Z., J.Z.W., L.M.M., R.S.B.B., R.A.dk.)
- Faculty of Medicine (J.G.E.Z., J.Z.W., L.M.M., R.S.B.B., R.A.dk.), University of Ottawa, Canada
| | - Lisa M Mielniczuk
- Department of Medicine (Cardiology), University of Ottawa Heart Institute, Canada (J.G.E.Z., J.Z.W., L.M.M., R.S.B.B., R.A.dk.)
- Faculty of Medicine (J.G.E.Z., J.Z.W., L.M.M., R.S.B.B., R.A.dk.), University of Ottawa, Canada
- Department of Cellular and Molecular Medicine (J.G.E.Z., L.M.M., R.S.B.B.), University of Ottawa, Canada
| | - Rob S B Beanlands
- Department of Medicine (Cardiology), University of Ottawa Heart Institute, Canada (J.G.E.Z., J.Z.W., L.M.M., R.S.B.B., R.A.dk.)
- Faculty of Medicine (J.G.E.Z., J.Z.W., L.M.M., R.S.B.B., R.A.dk.), University of Ottawa, Canada
- Department of Radiology (R.S.B.B.), University of Ottawa, Canada
- Department of Cellular and Molecular Medicine (J.G.E.Z., L.M.M., R.S.B.B.), University of Ottawa, Canada
| | - James A Fallavollita
- VA Western New York Healthcare System, Buffalo, NY (J.A.F., J.M.C.)
- Division of Cardiovascular Medicine, University at Buffalo, NY (J.A.F., J.M.C.)
| | - John M Canty
- VA Western New York Healthcare System, Buffalo, NY (J.A.F., J.M.C.)
- Division of Cardiovascular Medicine, University at Buffalo, NY (J.A.F., J.M.C.)
| | - Robert A deKemp
- Department of Medicine (Cardiology), University of Ottawa Heart Institute, Canada (J.G.E.Z., J.Z.W., L.M.M., R.S.B.B., R.A.dk.)
- Faculty of Medicine (J.G.E.Z., J.Z.W., L.M.M., R.S.B.B., R.A.dk.), University of Ottawa, Canada
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van Dongen IM, Elias J, Meijborg VM, De Bakker JM, Limpens J, Conrath CE, Henriques JP. Electrocardiographic changes after successful recanalization of a chronic total coronary occlusion. A systematic review and meta-analysis. CARDIOVASCULAR REVASCULARIZATION MEDICINE 2018; 19:221-228. [DOI: 10.1016/j.carrev.2017.09.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2017] [Accepted: 09/05/2017] [Indexed: 12/21/2022]
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Fallavollita JA, Dare JD, Carter RL, Baldwa S, Canty JM. Denervated Myocardium Is Preferentially Associated With Sudden Cardiac Arrest in Ischemic Cardiomyopathy: A Pilot Competing Risks Analysis of Cause-Specific Mortality. Circ Cardiovasc Imaging 2017; 10:CIRCIMAGING.117.006446. [PMID: 28794139 DOI: 10.1161/circimaging.117.006446] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Accepted: 06/19/2017] [Indexed: 12/20/2022]
Abstract
BACKGROUND Previous studies have identified multiple risk factors that are associated with total cardiac mortality. Nevertheless, identifying specific factors that distinguish patients at risk of arrhythmic death versus heart failure could better target patients likely to benefit from implantable cardiac defibrillators, which have no impact on nonsudden cardiac death. METHODS AND RESULTS We performed a pilot competing risks analysis of the National Institutes of Health-sponsored PAREPET trial (Prediction of Arrhythmic Events with Positron Emission Tomography). Death from cardiac causes was ascertained in subjects with ischemic cardiomyopathy (n=204) eligible for an implantable cardiac defibrillator for the primary prevention of sudden cardiac arrest after baseline clinical evaluation and imaging at enrollment (positron emission tomography and 2-dimensional echo). Mean age was 67±11 years with an ejection fraction of 27±9%, and 90% were men. During 4.1 years of follow-up, there were 33 sudden cardiac arrests (arrhythmic death or implantable cardiac defibrillator discharge for ventricular fibrillation or ventricular tachycardia >240 bpm) and 36 nonsudden cardiac deaths. Sudden cardiac arrest was correlated with a greater volume of denervated myocardium (defect of the positron emission tomography norepinephrine analog 11C-hydroxyephedrine), lack of angiotensin inhibition therapy, elevated B-type natriuretic peptide, and larger left ventricular end-diastolic volume index. In contrast, nonsudden cardiac death was associated with a higher resting heart rate, older age, elevated creatinine, larger left atrial volume index, and larger left ventricular end-diastolic volume index. CONCLUSIONS Distinct clinical, laboratory, and imaging variables are associated with cause-specific cardiac mortality in primary-prevention candidates with ischemic cardiomyopathy. If prospectively validated, these multivariable associations may help target specific therapies to those at the greatest risk of sudden and nonsudden cardiac death. CLINICAL TRIAL REGISTRATION URL: https://clinicaltrials.gov. Unique identifier: NCT01400334.
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Affiliation(s)
- James A Fallavollita
- From the VA Western New York Health Care System at Buffalo (J.A.F., S.B., J.M.C.), Clinical and Translational Science Institute (J.A.F., J.M.C.), Population Health Observatory (J.D.D., R.L.C.), Department of Medicine (J.A.F., S.B., J.M.C.), Department of Biostatistics (J.D.D., R.L.C.), Department of Physiology and Biophysics (J.M.C.), and Department of Biomedical Engineering (J.M.C.), Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, NY.
| | - Jonathan D Dare
- From the VA Western New York Health Care System at Buffalo (J.A.F., S.B., J.M.C.), Clinical and Translational Science Institute (J.A.F., J.M.C.), Population Health Observatory (J.D.D., R.L.C.), Department of Medicine (J.A.F., S.B., J.M.C.), Department of Biostatistics (J.D.D., R.L.C.), Department of Physiology and Biophysics (J.M.C.), and Department of Biomedical Engineering (J.M.C.), Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, NY
| | - Randolph L Carter
- From the VA Western New York Health Care System at Buffalo (J.A.F., S.B., J.M.C.), Clinical and Translational Science Institute (J.A.F., J.M.C.), Population Health Observatory (J.D.D., R.L.C.), Department of Medicine (J.A.F., S.B., J.M.C.), Department of Biostatistics (J.D.D., R.L.C.), Department of Physiology and Biophysics (J.M.C.), and Department of Biomedical Engineering (J.M.C.), Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, NY
| | - Sunil Baldwa
- From the VA Western New York Health Care System at Buffalo (J.A.F., S.B., J.M.C.), Clinical and Translational Science Institute (J.A.F., J.M.C.), Population Health Observatory (J.D.D., R.L.C.), Department of Medicine (J.A.F., S.B., J.M.C.), Department of Biostatistics (J.D.D., R.L.C.), Department of Physiology and Biophysics (J.M.C.), and Department of Biomedical Engineering (J.M.C.), Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, NY
| | - John M Canty
- From the VA Western New York Health Care System at Buffalo (J.A.F., S.B., J.M.C.), Clinical and Translational Science Institute (J.A.F., J.M.C.), Population Health Observatory (J.D.D., R.L.C.), Department of Medicine (J.A.F., S.B., J.M.C.), Department of Biostatistics (J.D.D., R.L.C.), Department of Physiology and Biophysics (J.M.C.), and Department of Biomedical Engineering (J.M.C.), Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, NY
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Bagnall A, Spyridopoulos I. The evidence base for revascularisation of chronic total occlusions. Curr Cardiol Rev 2015; 10:88-98. [PMID: 24694105 PMCID: PMC4021288 DOI: 10.2174/1573403x10666140331125659] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2013] [Revised: 12/15/2013] [Accepted: 01/20/2014] [Indexed: 01/22/2023] Open
Abstract
When patients with ischaemic heart disease are considered for revascularisation the Heart Team's aim is to choose a therapy that will provide complete relief of angina for an acceptable procedural risk. Complete functional revascularisation of ischaemic myocardium is thus the goal and for this reason the presence of a chronic total occlusion (CTO) - which remain the most technically challenging lesions to revascularise percutaneously - is the most common reason for selecting coronary artery bypass surgery. From the behaviour of Heart Teams it is clear that physicians believe that CTOs are important. Yet when faced with patients with CTOs for whom surgery appears excessive (e.g. nonproximal LAD) or too high risk, there remains a reluctance to undertake CTO PCI, despite significant recent advances in procedural success and safety and a considerable body of evidence supporting a survival benefit following successful CTO PCI. This article reviews the relationship between CTOs, symptoms of angina, ischaemia and left ventricular dysfunction and further explores the evidence relating their treatment to improved quality of life and prognosis in patients with these features.
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Affiliation(s)
| | - Ioakim Spyridopoulos
- Department of Cardiology, The Freeman Hospital, Freeman Road, Newcastle upon Tyne, NE7 7DN. UK.
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Pizzuto MF, Suzuki G, Banas MD, Heavey B, Fallavollita JA, Canty JM. Dissociation of hemodynamic and electrocardiographic indexes of myocardial ischemia in pigs with hibernating myocardium and sudden cardiac death. Am J Physiol Heart Circ Physiol 2013; 304:H1697-707. [PMID: 23585137 DOI: 10.1152/ajpheart.00166.2013] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Many survivors of sudden cardiac death (SCD) have normal global ventricular function and severe coronary artery disease but no evidence of symptomatic ischemia or infarction before the development of lethal ventricular arrhythmias, and the trigger for ventricular tachycardia (VT)/ventricular fibrillation (VF) remains unclear. We sought to identify the role of spontaneous ischemia and temporal hemodynamic factors preceding SCD using continuous telemetry of left ventricular (LV) pressure and the ECG for periods up to 5 mo in swine (n = 37) with hibernating myocardium who experience spontaneous VT/VF in the absence of heart failure or infarction. Hemodynamics and ST deviation at the time of VT/VF were compared with survivors with hibernating myocardium as well as sham controls. All episodes of VT/VF occurred during sympathetic activation and were initiated by single premature ventricular contractions, and the VT degenerated into VF in ∼ 30 s. ECG evidence of ischemia was infrequent and no different from those that survived. Baseline hemodynamics were no different among groups, but LV end-diastolic pressure during sympathetic activation was higher at the time of SCD (37 ± 4 vs. 26 ± 4 mmHg, P < 0.05) and the ECG demonstrated QT shortening (155 ± 4 vs. 173 ± 5 ms, P < 0.05). The week before SCD, both parameters were no different from survivors. These data indicate that there are no differences in the degree of sympathetic activation or hemodynamic stress when VT/VF develops in swine with hibernating myocardium. The transiently elevated LV end-diastolic pressure and QT shortening preceding VT/VF raises the possibility that electrocardiographically silent subendocardial ischemia and/or mechanoelectrical feedback serve as a trigger for the development of SCD in chronic ischemic heart disease.
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Affiliation(s)
- Matthew F Pizzuto
- Veterans Affairs Western New York Health Care System, Buffalo, NY, USA
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Abstract
The autonomic nervous system is the primary extrinsic control of cardiac performance, and altered autonomic activity has been recognized as an important factor in the progression of various cardiac pathologies. Molecular imaging techniques have been developed for global and regional interrogation of pre- and postsynaptic targets of the cardiac autonomic nervous system. Building on established work with the guanethidine analogue ¹²³I-metaiodobenzylguanidine (MIBG) for single-photon emission tomography (SPECT), development of radiotracers and protocols for positron emission tomography (PET) investigation of autonomic signaling has expanded. PET is limited in availability and requires specialized centers for radiosynthesis and interpretation, but the higher resolution allows for improved regional analysis and kinetic modeling provides more true quantification than is possible with SPECT. A wider array of radiolabeled catecholamines, analogues of catecholamines, and receptor ligands have been characterized and evaluated. Sympathetic neuronal PET tracers have shown promise in the identification of several cardiac pathologies. In particular, recent studies have elucidated a mechanistic role for heterogeneous sympathetic innervation in the development of lethal ventricular arrhythmias. Evaluation of cardiomyocyte adrenergic receptor expression and the parasympathetic nervous system has been slower to develop, with clinical studies beginning to emerge. This review summarizes the clinical and the experimental PET tracers currently available for autonomic imaging and discusses their application in health and cardiovascular disease, with particular emphasis on the major findings of the last decade.
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Affiliation(s)
- James T Thackeray
- Klinik für Nuklearmedizin, Medizinische Hochschule Hannover, Carl-Neuberg-Strasse 1, 30625 Hannover, Germany
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Fernandez SF, Ovchinnikov V, Canty JM, Fallavollita JA. Hibernating myocardium results in partial sympathetic denervation and nerve sprouting. Am J Physiol Heart Circ Physiol 2012; 304:H318-27. [PMID: 23125211 DOI: 10.1152/ajpheart.00810.2011] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Hibernating myocardium due to chronic repetitive ischemia is associated with regional sympathetic nerve dysfunction and spontaneous arrhythmic death in the absence of infarction. Although inhomogeneity in regional sympathetic innervation is an acknowledged substrate for sudden death, the mechanism(s) responsible for these abnormalities in viable, dysfunctional myocardium (i.e., neural stunning vs. sympathetic denervation) and their association with nerve sprouting are unknown. Accordingly, markers of sympathetic nerve function and nerve sprouting were assessed in subendocardial tissue collected from chronically instrumented pigs with hibernating myocardium (n = 18) as well as sham-instrumented controls (n = 7). Hibernating myocardium exhibited evidence of partial sympathetic denervation compared with the normally perfused region and sham controls, with corresponding regional reductions in tyrosine hydroxylase protein (-32%, P < 0.001), norepinephrine uptake transport protein (-25%, P = 0.01), and tissue norepinephrine content (-45%, P < 0.001). Partial denervation induced nerve sprouting with regional increases in nerve growth factor precursor protein (31%, P = 0.01) and growth associated protein-43 (38%, P < 0.05). All of the changes in sympathetic nerve markers were similar in animals that developed sudden death (n = 9) compared with electively terminated pigs with hibernating myocardium (n = 9). In conclusion, sympathetic nerve dysfunction in hibernating myocardium is most consistent with partial sympathetic denervation and is associated with regional nerve sprouting. The extent of sympathetic remodeling is similar in animals that develop sudden death compared with survivors; this suggests that sympathetic remodeling in hibernating myocardium is not an independent trigger for sudden death. Nevertheless, sympathetic remodeling likely contributes to electrical instability in combination with other factors.
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Affiliation(s)
- Stanley F Fernandez
- Center for Research in Cardiovascular Medicine, University at Buffalo, Buffalo, NY 14203, USA
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Slezak J, Tribulova N, Okruhlicova L, Dhingra R, Bajaj A, Freed D, Singal P. Hibernating myocardium: pathophysiology, diagnosis, and treatment. Can J Physiol Pharmacol 2009; 87:252-65. [PMID: 19370079 DOI: 10.1139/y09-011] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Comprehensive management of patients with chronic ischemic disease is a critically important component of clinical practice. Cardiac myocytes have the potential to adapt to limited flow conditions by adjusting contractile function, reducing metabolism, conserving resources, and preserving myocardial integrity to cope with an oxygen and (or) nutrition shortage. A prime metabolic feature of cardiac myocytes affected by chronic ischemia is the return to a fetal gene pattern with predominance of carbohydrates as the substrate for energy. Structural adaptation with multiple intracellular changes is part of the remodeling process in hibernating myocardium. Transmural heterogeneity, which defines the pattern of injury in ventricular cardiomyocytes and the response to chronic ischemia, is a multifactorial process originating from functional, metabolic, and flow differences in subendocardial and subepicardial regions. Autophagy is typically activated in hibernating myocardium and has been identified as a prosurvival mechanism. Chronic ischemia is associated with changes in the number, size, and distribution of gap junctions and may give rise to conduction disturbances and arrhythmogenesis. Differentiation between viable and nonviable myocardium by assessing sensitivity of inotropic reserve is a crucial diagnostic tool that is correlated with the prognosis and outcome for improved contractility after restoration of blood perfusion in afflicted myocardium.Reliable and accurate diagnosis of ischemic, scar, and viable tissues is critical for recover strategies. Although early surgical reinstitution of blood flow is most effective in restoring physiologic function of the hibernating myocardium, several new approaches offer promising alternatives. Among others, vascular endothelial growth factor and fibroblast growth factor-2 (FGF-2), especially its lo-FGF-2 isoform, have been shown to be effective in rapid neovascularization. Substances such as statins, resveratrol, some hormones, and omega-3 fatty acids can improve recovery effect in chronically underperfused hearts. For patients with drug-refractory ischemia, intramyocardial transplantation of stem cells into predefined areas of the heart can enhance vascularization and have beneficial effects on cardiac function. This review of ischemic injury, its heterogeneity, accurate diagnosis, and newer methods of treatment, shows there is much information and tremendous hope for better management of patients with coronary heart disease.
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Affiliation(s)
- Jan Slezak
- Institute of Cardiovascular Sciences, St. Boniface General Hospital Research Centre, Faculty of Medicine, University of Manitoba, Winnipeg, MB, Canada
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Zhang X, Liu XJ, Hu S, Schindler TH, Tian Y, He ZX, Gao R, Wu Q, Wei H, Sayre JW, Schelbert HR. Long-Term Survival of Patients with Viable and Nonviable Aneurysms Assessed by 99mTc-MIBI SPECT and 18F-FDG PET: A Comparative Study of Medical and Surgical Treatment. J Nucl Med 2008; 49:1288-98. [DOI: 10.2967/jnumed.107.046730] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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