1
|
Cook CM, Howard JP, Ahmad Y, Shun-Shin MJ, Sethi A, Clesham GJ, Tang KH, Nijjer SS, Kelly PA, Davies JR, Malik IS, Kaprielian R, Mikhail G, Petraco R, Warisawa T, Al-Janabi F, Karamasis GV, Mohdnazri S, Gamma R, Stathogiannis KE, de Waard GA, Al-Lamee R, Keeble TR, Mayet J, Sen S, Francis DP, Davies JE. Comparing invasive hemodynamic responses in adenosine hyperemia versus physical exercise stress in chronic coronary syndromes. Int J Cardiol 2021; 342:7-14. [PMID: 34358553 DOI: 10.1016/j.ijcard.2021.07.064] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 07/04/2021] [Accepted: 07/30/2021] [Indexed: 01/10/2023]
Abstract
OBJECTIVES Adenosine hyperemia is an integral component of the physiological assessment of obstructive coronary artery disease in patients with chronic coronary syndrome (CCS). The aim of this study was to compare systemic, coronary and microcirculatory hemodynamics between intravenous (IV) adenosine hyperemia versus physical exercise stress in patients with CCS and coronary stenosis. METHODS Twenty-three patients (mean age, 60.6 ± 8.1 years) with CCS and single-vessel coronary stenosis underwent cardiac catheterization. Continuous trans-stenotic coronary pressure-flow measurements were performed during: i) IV adenosine hyperemia, and ii) physical exercise using a catheter-table-mounted supine ergometer. Systemic, coronary and microcirculatory hemodynamic responses were compared between IV adenosine and exercise stimuli. RESULTS Mean stenosis diameter was 74.6% ± 10.4. Median (interquartile range) FFR was 0.54 (0.44-0.72). At adenosine hyperemia versus exercise stress, mean aortic pressure (Pa, 91 ± 16 mmHg vs 99 ± 15 mmHg, p < 0.0001), distal coronary pressure (Pd, 58 ± 21 mmHg vs 69 ± 24 mmHg, p < 0.0001), trans-stenotic pressure ratio (Pd/Pa, 0.63 ± 0.18 vs 0.69 ± 0.19, p < 0.0001), microvascular resistance (MR, 2.9 ± 2.2 mmHg.cm-1.sec-1 vs 4.2 ± 1.7 mmHg.cm-1.sec-1, p = 0.001), heart rate (HR, 80 ± 15 bpm vs 85 ± 21 bpm, p = 0.02) and rate-pressure product (RPP, 7522 ± 2335 vs 9077 ± 3200, p = 0.0001) were all lower. Conversely, coronary flow velocity (APV, 23.7 ± 9.5 cm/s vs 18.5 ± 6.8 cm/s, p = 0.02) was higher. Additionally, temporal changes in Pa, Pd, Pd/Pa, MR, HR, RPP and APV during IV adenosine hyperemia versus exercise were all significantly different (p < 0.05 for all). CONCLUSIONS In patients with CCS and coronary stenosis, invasive hemodynamic responses differed markedly between IV adenosine hyperemia versus physical exercise stress. These differences were observed across systemic, coronary and microcirculatory hemodynamics.
Collapse
Affiliation(s)
- Christopher M Cook
- Imperial College London, London, UK; Essex Cardiothoracic Centre, Basildon, UK.
| | | | | | | | | | - Gerald J Clesham
- Essex Cardiothoracic Centre, Basildon, UK; Anglia Ruskin University, UK
| | - Kare H Tang
- Essex Cardiothoracic Centre, Basildon, UK; Anglia Ruskin University, UK
| | | | | | - John R Davies
- Essex Cardiothoracic Centre, Basildon, UK; Anglia Ruskin University, UK
| | | | | | | | | | | | - Firas Al-Janabi
- Essex Cardiothoracic Centre, Basildon, UK; Anglia Ruskin University, UK
| | | | - Shah Mohdnazri
- Essex Cardiothoracic Centre, Basildon, UK; Anglia Ruskin University, UK
| | - Reto Gamma
- Essex Cardiothoracic Centre, Basildon, UK
| | | | | | | | - Thomas R Keeble
- Essex Cardiothoracic Centre, Basildon, UK; Anglia Ruskin University, UK
| | | | | | | | | |
Collapse
|
2
|
Additional decrease in fractional flow reserve in the left anterior descending artery after hand-grip exercise during pharmacological coronary hyperemia. Heart Vessels 2021; 36:1611-1616. [PMID: 33830316 DOI: 10.1007/s00380-021-01846-7] [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] [Received: 12/19/2020] [Accepted: 04/02/2021] [Indexed: 10/21/2022]
Abstract
Maximal hyperemia at the time of fractional flow reserve (FFR) measurement is generally induced by vasodilators, even when hyperemia at the onset of angina symptoms is caused by exercise stress. This study was designed to evaluate whether pharmacological hyperemia could be used as a substitute for exercise-induced hyperemia during FFR measurement. Twenty-two patients with angiographically intermediate stenosis in the left anterior descending artery (LAD) were prospectively enrolled. FFR measurements were repeated in the following two conditions while the pressure-wire was positioned in the same segment; (1) during pharmacological hyperemia induced by intracoronary administration of 2 mg nicorandil, (2) immediately after isotonic hand-grip exercise for 90 s (50% of maximum voluntary contraction) followed by intracoronary administration of 2 mg nicorandil. Isotonic hand-grip exercise increased systolic blood pressure (130 ± 19 versus 150 ± 22 mmHg, p < 0.001), heart rate (71 ± 11 versus 79 ± 13 bpm, p < 0.001), and cardiac output (5.1 ± 1.2 versus 5.9 ± 1.5 L/min, p < 0.001), which indicated an increased afterload on the left ventricle. After the hand-grip exercise, FFR significantly decreased from 0.86 ± 0.06 to 0.84 ± 0.06 (p < 0.001). A percent increase in systolic blood pressure and cardiac output after hand-grip exercise strongly correlated with ΔFFR (r = - 0.65, p < 0.001 and r = - 0.55, p < 0.001, respectively). An increase in cardiac output with hand-grip exercise during pharmacological hyperemia could induce an additional decrease in FFR for lesions located in the LAD.
Collapse
|
3
|
Yamagishi M, Tamaki N, Akasaka T, Ikeda T, Ueshima K, Uemura S, Otsuji Y, Kihara Y, Kimura K, Kimura T, Kusama Y, Kumita S, Sakuma H, Jinzaki M, Daida H, Takeishi Y, Tada H, Chikamori T, Tsujita K, Teraoka K, Nakajima K, Nakata T, Nakatani S, Nogami A, Node K, Nohara A, Hirayama A, Funabashi N, Miura M, Mochizuki T, Yokoi H, Yoshioka K, Watanabe M, Asanuma T, Ishikawa Y, Ohara T, Kaikita K, Kasai T, Kato E, Kamiyama H, Kawashiri M, Kiso K, Kitagawa K, Kido T, Kinoshita T, Kiriyama T, Kume T, Kurata A, Kurisu S, Kosuge M, Kodani E, Sato A, Shiono Y, Shiomi H, Taki J, Takeuchi M, Tanaka A, Tanaka N, Tanaka R, Nakahashi T, Nakahara T, Nomura A, Hashimoto A, Hayashi K, Higashi M, Hiro T, Fukamachi D, Matsuo H, Matsumoto N, Miyauchi K, Miyagawa M, Yamada Y, Yoshinaga K, Wada H, Watanabe T, Ozaki Y, Kohsaka S, Shimizu W, Yasuda S, Yoshino H. JCS 2018 Guideline on Diagnosis of Chronic Coronary Heart Diseases. Circ J 2021; 85:402-572. [PMID: 33597320 DOI: 10.1253/circj.cj-19-1131] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
| | - Nagara Tamaki
- Department of Radiology, Kyoto Prefectural University of Medicine Graduate School
| | - Takashi Akasaka
- Department of Cardiovascular Medicine, Wakayama Medical University
| | - Takanori Ikeda
- Department of Cardiovascular Medicine, Toho University Graduate School
| | - Kenji Ueshima
- Center for Accessing Early Promising Treatment, Kyoto University Hospital
| | - Shiro Uemura
- Department of Cardiology, Kawasaki Medical School
| | - Yutaka Otsuji
- Second Department of Internal Medicine, University of Occupational and Environmental Health, Japan
| | - Yasuki Kihara
- Department of Cardiovascular Medicine, Hiroshima University Graduate School of Biomedical and Health Sciences
| | - Kazuo Kimura
- Division of Cardiology, Yokohama City University Medical Center
| | - Takeshi Kimura
- Department of Cardiovascular Medicine, Kyoto University Graduate School
| | | | | | - Hajime Sakuma
- Department of Radiology, Mie University Graduate School
| | | | - Hiroyuki Daida
- Department of Cardiovascular Medicine, Juntendo University Graduate School
| | | | - Hiroshi Tada
- Department of Cardiovascular Medicine, University of Fukui
| | | | - Kenichi Tsujita
- Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kumamoto University
| | | | - Kenichi Nakajima
- Department of Functional Imaging and Artificial Intelligence, Kanazawa Universtiy
| | | | - Satoshi Nakatani
- Division of Functional Diagnostics, Department of Health Sciences, Osaka University Graduate School of Medicine
| | | | - Koichi Node
- Department of Cardiovascular Medicine, Saga University
| | - Atsushi Nohara
- Division of Clinical Genetics, Ishikawa Prefectural Central Hospital
| | | | | | - Masaru Miura
- Department of Cardiology, Tokyo Metropolitan Children's Medical Center
| | | | | | | | - Masafumi Watanabe
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University
| | - Toshihiko Asanuma
- Division of Functional Diagnostics, Department of Health Sciences, Osaka University Graduate School
| | - Yuichi Ishikawa
- Department of Pediatric Cardiology, Fukuoka Children's Hospital
| | - Takahiro Ohara
- Division of Community Medicine, Tohoku Medical and Pharmaceutical University
| | - Koichi Kaikita
- Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kumamoto University
| | - Tokuo Kasai
- Department of Cardiology, Uonuma Kinen Hospital
| | - Eri Kato
- Department of Cardiovascular Medicine, Department of Clinical Laboratory, Kyoto University Hospital
| | | | - Masaaki Kawashiri
- Department of Cardiovascular and Internal Medicine, Kanazawa University
| | - Keisuke Kiso
- Department of Diagnostic Radiology, Tohoku University Hospital
| | - Kakuya Kitagawa
- Department of Advanced Diagnostic Imaging, Mie University Graduate School
| | - Teruhito Kido
- Department of Radiology, Ehime University Graduate School
| | | | | | | | - Akira Kurata
- Department of Radiology, Ehime University Graduate School
| | - Satoshi Kurisu
- Department of Cardiovascular Medicine, Hiroshima University Graduate School of Biomedical and Health Sciences
| | - Masami Kosuge
- Division of Cardiology, Yokohama City University Medical Center
| | - Eitaro Kodani
- Department of Internal Medicine and Cardiology, Nippon Medical School Tama Nagayama Hospital
| | - Akira Sato
- Department of Cardiology, University of Tsukuba
| | - Yasutsugu Shiono
- Department of Cardiovascular Medicine, Wakayama Medical University
| | - Hiroki Shiomi
- Department of Cardiovascular Medicine, Kyoto University Graduate School
| | - Junichi Taki
- Department of Nuclear Medicine, Kanazawa University
| | - Masaaki Takeuchi
- Department of Laboratory and Transfusion Medicine, Hospital of the University of Occupational and Environmental Health, Japan
| | | | - Nobuhiro Tanaka
- Department of Cardiology, Tokyo Medical University Hachioji Medical Center
| | - Ryoichi Tanaka
- Department of Reconstructive Oral and Maxillofacial Surgery, Iwate Medical University
| | | | | | - Akihiro Nomura
- Innovative Clinical Research Center, Kanazawa University Hospital
| | - Akiyoshi Hashimoto
- Department of Cardiovascular, Renal and Metabolic Medicine, Sapporo Medical University
| | - Kenshi Hayashi
- Department of Cardiovascular Medicine, Kanazawa University Hospital
| | - Masahiro Higashi
- Department of Radiology, National Hospital Organization Osaka National Hospital
| | - Takafumi Hiro
- Division of Cardiology, Department of Medicine, Nihon University
| | | | - Hitoshi Matsuo
- Department of Cardiovascular Medicine, Gifu Heart Center
| | - Naoya Matsumoto
- Division of Cardiology, Department of Medicine, Nihon University
| | | | | | | | - Keiichiro Yoshinaga
- Department of Diagnostic and Therapeutic Nuclear Medicine, Molecular Imaging at the National Institute of Radiological Sciences
| | - Hideki Wada
- Department of Cardiology, Juntendo University Shizuoka Hospital
| | - Tetsu Watanabe
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University
| | - Yukio Ozaki
- Department of Cardiology, Fujita Medical University
| | - Shun Kohsaka
- Department of Cardiology, Keio University School of Medicine
| | - Wataru Shimizu
- Department of Cardiovascular Medicine, Nippon Medical School
| | - Satoshi Yasuda
- Department of Cardiovascular Medicine, Tohoku University Graduate School of Medicine
| | | | | |
Collapse
|
4
|
Rischpler C, Totzeck M. Are you stressed? J Nucl Cardiol 2019; 26:1898-1900. [PMID: 29948893 DOI: 10.1007/s12350-018-1332-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Accepted: 05/22/2018] [Indexed: 11/26/2022]
Affiliation(s)
- C Rischpler
- Department of Nuclear Medicine, University Hospital Essen, University of Duisburg-Essen, Essen, Germany.
| | - M Totzeck
- Department of Cardiology and Vascular Medicine, University Hospital Essen, West German Heart and Vascular Center, University of Duisburg, Essen, Germany
| |
Collapse
|
5
|
Ker WDS, Neves DGD, Magalhães TA, Santos AASMDD, Mesquita CT, Nacif MS. Myocardial Perfusion by Coronary Computed Tomography in the Evaluation of Myocardial Ischemia: Simultaneous Stress Protocol with SPECT. Arq Bras Cardiol 2019; 113:1092-1101. [PMID: 31596324 PMCID: PMC7021272 DOI: 10.5935/abc.20190201] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2018] [Accepted: 02/13/2019] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND Functional assessment to rule out myocardial ischemia using coronary computed tomography angiography (CCTA) is extremely important and data on the Brazilian population are still limited. OBJECTIVE To assess the diagnostic performance of myocardial perfusion by CCTA in the detection of severe obstructive coronary artery disease (CAD) compared with single-photon emission computerized tomography (SPECT). To analyze the importance of anatomical knowledge to understand the presence of myocardial perfusion defects on SPECT imaging that is not identified on computed tomography (CT) scan. METHOD A total of 35 patients were evaluated by a simultaneous pharmacologic stress protocol. Fisher's exact test was used to compare proportions. The patients were grouped according to the presence or absence of significant CAD. The area under the ROC curve was used to identify the diagnostic performance of CCTA and SPECT in perfusion assessment. P < 0.05 values were considered statistically significant. RESULTS For detection of obstructive CAD, CT myocardial perfusion analysis yielded an area under the ROC curve of 0.84 [a 95% confidence interval (CI95%): 0.67-0.94, p < 0.001]. SPECT myocardial perfusion imaging, on the other hand, showed an AUC of 0.58 (95% CI 0.40 - 0.74, p < 0.001). In this study, false-positive results with SPECT are described. CONCLUSION Myocardial perfusion analysis by CTA displays satisfactory results compared to SPECT in the detection of obstructive CAD. CCTA can rule out false-positive results of SPECT.
Collapse
Affiliation(s)
- Wilter Dos Santos Ker
- Hospital Universitário Antonio Pedro, Niterói, RJ - Brazil.,Universidade Federal Fluminense, Niterói, RJ - Brazil
| | | | - Tiago Augusto Magalhães
- Complexo Hospital de Clínicas da Universidade Federal do Paraná (CHC-UFPR), Curitiba, PR - Brazil
| | | | | | - Marcelo Souto Nacif
- Hospital Universitário Antonio Pedro, Niterói, RJ - Brazil.,Universidade Federal Fluminense, Niterói, RJ - Brazil.,Complexo Hospital de Clínicas da Universidade Federal do Paraná (CHC-UFPR), Curitiba, PR - Brazil
| |
Collapse
|
6
|
Al-Oweidi AS, Albabtain H, Kharabsheh SM, Kimme P, Almustafa M, Seder S, Shoukri M, Fathala AL. Prevalence and predictors of myocardial ischemia by preoperative myocardial perfusion single photon emission computed tomography in patients undergoing noncardiac surgery. Ann Saudi Med 2017; 37:461-468. [PMID: 29229895 PMCID: PMC6074119 DOI: 10.5144/0256-4947.2017.461] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND The prevalence and predictors of myocardial ischemia before noncardiac surgery are unknown. In addition the predictive value of myocardial perfusion single-photon emission computed tomography (SPECT) before noncardiac in individual patients is uncertain. OBJECTIVE Evaluate the prevalence and predictors of myocardial ischemia before noncardiac surgery, and determine the postoperative cardiac outcome based on results of myocardial perfusion SPECT. DESIGN Retrospective. SETTING Single tertiary care center. PATIENTS AND METHODS We reviewed the records of adult patients diagnosed with myocardial ischemia by myocardial perfusion SPECT who were undergoing noncardiac surgery. Myocardial perfusion SPECT had been performed within 4 weeks prior to noncardiac surgery requiring general anesthesia. MAIN OUTCOME MEASURES Prevalence of abnormal myocardial perfusion SPECT results on preoperative evaluation; abnormal myocardial perfusion SPECT results as a predictor for postoperative cardiac events such as cardiac death, nonfatal myocardial infarction, and unstable angina. RESULTS Of 131 patients who underwent noncardiac surgery from February 2015 to April 2016, 84 (64%) patients were female and the mean (SD) age was 64.1 (13.6) years. The prevalence of abnormal myocardial perfusion SPECT was 18% (24 of 131). Normal myocardial perfusion SPECT was highly predictive (up to 100%), but a positive myocardial perfusion SPECT had low positive predictive value (4%). Variables associated with an abnormal myocardial perfusion SPECT included ischemic heart disease, congestive heart failure, ASA score of 3 or more, limited exercise capacity (less than 4 METs), male sex, hypercholesterolemia, hypertension, smoking, and abnormal ECG. In a multivariable analysis, history of ischemic heart disease and history of smoking were significant predictors of abnormal myocardial perfusion SPECT (P=.001, and .029, respectively). CONCLUSIONS Because of the low positive predictive value of myocardial perfusion SPECT, utilization of the technique in the workup of cardiac patients undergoing noncardiac surgery has been inappropriate. Myocardial perfusion SPECT should be restricted to only clearly defined appropriate use criteria. LIMITATIONS Relatively small number of patients and retrospective design.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | - Ahmed L Fathala
- Dr. Ahmed L. Fathala, Department of Radiology, MBC 28,, King Faisal Specialist Hospital and Research Centre,, PO Box 3354, Riyadh 11211, Saudi Arabia, T: +966-11-4647272 F: +966-11-4424841, , ORCID ID: http://orcid.org/0000.0002-2436-4226
| |
Collapse
|
7
|
Pharmacologic manipulation of coronary vascular physiology for the evaluation of coronary artery disease. Pharmacol Ther 2013; 140:121-32. [DOI: 10.1016/j.pharmthera.2013.06.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Accepted: 05/23/2013] [Indexed: 11/24/2022]
|
8
|
Development of a theory for generating regional cardiac perfusion images during coronary angiography in the coronary angiography lab. Int J Cardiovasc Imaging 2013; 30:9-19. [PMID: 24122453 DOI: 10.1007/s10554-013-0304-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Accepted: 09/30/2013] [Indexed: 10/26/2022]
Abstract
The purpose of this study was to develop a novel theory and method for generating regional myocardial perfusion images using fluoroscopy in the coronary angiography lab. We modified the Kety model to introduce the Patlak plot method for two-dimensional fluoroperfusion (FP) imaging. For evaluation, seven porcine models of myocardial ischemia with stenosis in the left coronary artery were prepared. Rest and stress FP imaging were performed using cardiovascular X-ray imaging equipment during the injection of iopamidol via the left main coronary artery. Images were acquired and retrospectively ECG gated at 80 % of the R-R interval. FP myocardial blood flow (MBF) was obtained using the Patlak plot method applied to time-intensity curve data of the proximal artery and myocardium. The results were compared to microsphere MBF measurements. Time-intensity curves were also used to generate color-coded FP maps. There was a moderate linear correlation between the calculated FP MBF and the microsphere MBF (y = 0.9758x + 0.5368, R² = 0.61). The color-coded FP maps were moderately correlated with the regional distribution of flow. This novel method of first-pass contrast-enhanced two-dimensional fluoroscopic imaging can quantify MBF and provide color coded FP maps representing regional myocardial perfusion.
Collapse
|
9
|
Fatima N, Uz Zaman M, Ishaq M, Rasheed SZ, Baloch DJ, Wali A, Bano J, Rehman K. Higher events rate in patients with a normal gated myocardial perfusion imaging with dipyridamole than exercise: "Run for reliability". INDIAN JOURNAL OF NUCLEAR MEDICINE : IJNM : THE OFFICIAL JOURNAL OF THE SOCIETY OF NUCLEAR MEDICINE, INDIA 2012; 27:172-5. [PMID: 23919070 PMCID: PMC3728738 DOI: 10.4103/0972-3919.112722] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVE The aim of this is to evaluate the negative predictive value (NPV) of a normal gated myocardial perfusion imaging (NGMPI) with exercise and dipyridamole in a propensity matched population. MATERIALS AND METHODS This is a prospective study conducted at Nuclear Cardiology Department of Karachi Institute of Heart Diseases, Karachi from December 2008 until June 2010. A total of 809 patients with a NGMPI with adequate exercise (558/809) or dipyridamole (251/809) stress were included and followed-up for 12-30 months (mean 24 ± 3 months) for fatal or non-fatal myocardial infarctions (MI). RESULTS Mean ejection fraction (%), end diastolic volume (ml), and end systolic volume (ml) in exercise and dipyridamole cohorts were (72 ± 08, 66 ± 11), (68 ± 13, 81 ± 17), and (19 ± 11, 26 ± 12) respectively. On follow-up, in dipyridamole cohort 2 fatal and 6 non-fatal MIs were reported. While in exercise cohort only 2 non-fatal MIs were reported. The NPV of a NGMPI with exercise was 99.7% (95% confidence interval [CI] 98.93-99.96%) with an event rate of 0.3% (95% CI; 0.03-0.6%) and annualized event rate of 0.15%. The NPV of NGMPI with dipyridamole was 96.80% (95% CI; 2.2-4.3%) with an event rate of 3.2% (95% CI; 1.39-3.83%) and annualized event rate of approximately 1.6%. Event free survival for dipyridamole group was significantly lower than exercise analyzed by Log-rank test (14.509, P < 0.001). CONCLUSION A NGMPI with dipyridamole stress has higher event rate (low-NPV) as compared with exercise and this raises concern over its credibility to label these patients into low-risk group.
Collapse
Affiliation(s)
- Nosheen Fatima
- Department of Nuclear Cardiology, Karachi Institute of Heart Diseases, Karachi, Pakistan ; Department of Nuclear Medicine, Dr Ziauddin Medical University, Karachi, Pakistan
| | | | | | | | | | | | | | | |
Collapse
|
10
|
Lee JC, Fraser JF, Barnett AG, Johnson LP, Wilson MG, McHenry CM, Walters DL, Warnholtz CR, Khafagi FA. Effect of caffeine on adenosine-induced reversible perfusion defects assessed by automated analysis. J Nucl Cardiol 2012; 19:474-81. [PMID: 22302182 DOI: 10.1007/s12350-012-9517-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2011] [Accepted: 01/07/2012] [Indexed: 10/14/2022]
Abstract
OBJECTIVES This prospective study investigated the effects of caffeine ingestion on the extent of adenosine-induced perfusion abnormalities during myocardial perfusion imaging (MPI). METHODS Thirty patients with inducible perfusion abnormalities on standard (caffeineabstinent) adenosine MPI underwent repeat testing with supplementary coffee intake. Baseline and test MPIs were assessed for stress percent defect, rest percent defect, and percent defect reversibility. Plasma levels of caffeine and metabolites were assessed on both occasions and correlated with MPI findings. RESULTS Despite significant increases in caffeine [mean difference 3,106 μg/L (95% CI 2,460 to 3,752 μg/L; P < .001)] and metabolite concentrations over a wide range, there was no statistically significant change in stress percent defect and percent defect reversibility between the baseline and test scans. The increase in caffeine concentration between the baseline and the test phases did not affect percent defect reversibility (average change -0.003 for every 100 μg/L increase; 95% CI -0.17 to 0.16; P = .97). CONCLUSION There was no significant relationship between the extent of adenosine-induced coronary flow heterogeneity and the serum concentration of caffeine or its principal metabolites. Hence, the stringent requirements for prolonged abstinence from caffeine before adenosine MPI - based on limited studies - appear ill-founded.
Collapse
Affiliation(s)
- Joseph C Lee
- Department of Nuclear Medicine, The Prince Charles Hospital, Chermside, QLD 4032, Australia.
| | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Techasith T, Cury RC. Stress myocardial CT perfusion: an update and future perspective. JACC Cardiovasc Imaging 2011; 4:905-16. [PMID: 21835384 DOI: 10.1016/j.jcmg.2011.04.017] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2011] [Revised: 03/31/2011] [Accepted: 04/07/2011] [Indexed: 10/17/2022]
Abstract
Coronary computed tomography angiography (CTA) has been shown by several multicenter trials to have excellent diagnostic accuracy in the detection and exclusion of significant coronary stenosis. However, a major limitation of coronary CTA is that the physiological significance of stenotic lesions identified is often unknown. Stress myocardial computed tomography perfusion (CTP) is a novel examination that provides both anatomic and physiological information (i.e., myocardial perfusion). Multiple single-center studies have established the feasibility of stress myocardial CTP. Furthermore, it has been illustrated that a combined CTA/CTP protocol improves the diagnostic accuracy to detect hemodynamic significant stenosis as compared with CTA alone; this combined protocol can also be accomplished at a radiation dose comparable to nuclear myocardial perfusion imaging exams. Although initial results hold some promise, stress myocardial CTP is a modality in its infancy. Further research is required to define, validate, and optimize this new technique. However, it is a modality with significant potential, particularly in the evaluation of chest pain patients, given the advantages of short exam time and comprehensive data acquisition. This review highlights how to perform and interpret stress myocardial CTP, summarizes the current literature, and discusses some future directions.
Collapse
|
12
|
Tejani FH, Thompson RC, Iskandrian AE, McNutt BE, Franks B. Effect of caffeine on SPECT myocardial perfusion imaging during regadenoson pharmacologic stress: rationale and design of a prospective, randomized, multicenter study. J Nucl Cardiol 2011; 18:73-81. [PMID: 21082298 DOI: 10.1007/s12350-010-9311-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2010] [Accepted: 10/17/2010] [Indexed: 10/18/2022]
Abstract
BACKGROUND Caffeine attenuates the coronary hyperemic response to adenosine by competitive A₂(A) receptor blockade. This study aims to determine whether oral caffeine administration compromises diagnostic accuracy in patients undergoing vasodilator stress myocardial perfusion imaging (MPI) with regadenoson, a selective adenosine A(2A) agonist. METHODS This multicenter, randomized, double-blind, placebo-controlled, parallel-group study includes patients with suspected coronary artery disease who regularly consume caffeine. Each participant undergoes three SPECT MPI studies: a rest study on day 1 (MPI-1); a regadenoson stress study on day 3 (MPI-2), and a regadenoson stress study on day 5 with double-blind administration of oral caffeine 200 or 400 mg or placebo capsules (MPI-3; n = 90 per arm). Only participants with ≥ 1 reversible defect on the second MPI study undergo the subsequent stress MPI test. The primary endpoint is the difference in the number of reversible defects on the two stress tests using a 17-segment model. Pharmacokinetic/pharmacodynamic analyses will evaluate the effect of caffeine on the regadenoson exposure-response relationship. Safety will also be assessed. CONCLUSION The results of this study will show whether the consumption of caffeine equivalent to 2-4 cups of coffee prior to an MPI study with regadenoson affects the diagnostic validity of stress testing (ClinicalTrials.gov number, NCT00826280).
Collapse
|
13
|
Hassan M, York KM, Li Q, Lucey DG, Fillingim RB, Sheps DS. Variability of myocardial ischemic responses to mental versus exercise or adenosine stress in patients with coronary artery disease. J Nucl Cardiol 2008; 15:518-25. [PMID: 18674719 DOI: 10.1016/j.nuclcard.2008.04.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2007] [Revised: 04/01/2008] [Accepted: 04/01/2008] [Indexed: 01/09/2023]
Abstract
BACKGROUND Mental stress precipitates myocardial ischemia in a significant percentage of coronary artery disease (CAD) patients. Exercise or adenosine stresses produce different physiologic responses and cause myocardial ischemia via different mechanisms. Little is known about the comparative severity and location of myocardial ischemia provoked by these different stressors. In this study we sought to compare the within-individual ischemic responses to mental versus exercise or adenosine stress in a cohort of CAD patients. METHODS AND RESULTS All patients underwent mental stress and either exercise or adenosine testing within a 1-week period. Mental stress was induced via a public speaking task. Rest-stress myocardial perfusion imaging was used with all testing protocols. Participants were 187 patients (65 women [35%]) with a documented history of CAD and a mean age of 64 +/- 9 years. Mental stress-induced myocardial ischemia (MSIMI) was less prevalent and frequently of less magnitude than exercise- or adenosine-induced ischemia. Ischemia induced by exercise or adenosine testing did not accurately predict the development or the location of MSIMI. The overall concordance between these stressors for provoking ischemia was weak (percent agreement, 71%; kappa [+/- SE], 0.26 +/- 0.07). In a minority of patients (11%) mental stress provoked ischemia in the absence of exercise- or adenosine-induced ischemia. Moreover, in patients who had myocardial ischemia during both stressors, there were significant within-individual differences in the coronary artery distribution of the ischemic regions. MSIMI was more likely to occur in a single-vessel distribution (86%) compared with exercise- or adenosine-induced ischemia (54%). The stressors had moderate agreement if the ischemic region was in the right coronary artery territory (percent agreement, 76%; kappa, 0.52 +/- 0.19) or the left anterior descending coronary artery (percent agreement, 76%; kappa, 0.51 +/- 0.19) and significantly lower agreement in the left circumflex territory (percent agreement, 62%; kappa, 0.22 +/- 0.18). CONCLUSIONS Our findings indicate that mental and exercise or adenosine stresses provoke different myocardial ischemic responses. These observations suggest that exercise or adenosine testing may not adequately assess the likelihood of occurrence or severity of MSIMI and that different mechanisms are operative in each condition.
Collapse
Affiliation(s)
- Mustafa Hassan
- Division of Cardiology, Department of Medicine, University of Florida, Gainesville, FL, USA.
| | | | | | | | | | | |
Collapse
|
14
|
Symptom-limited exercise combined with dipyridamole stress: prognostic value in assessment of known or suspected coronary artery disease by use of gated SPECT imaging. J Nucl Cardiol 2008; 15:42-56. [PMID: 18242479 DOI: 10.1016/j.nuclcard.2007.09.025] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2007] [Accepted: 09/10/2007] [Indexed: 11/24/2022]
Abstract
BACKGROUND Combining vasodilator and exercise stress reduces noncardiac side effects, improves image quality, and enhances the detection of ischemia, compared with suboptimal exercise or vasodilator stress alone. However, prognostic data with combined protocols are limited. METHODS AND RESULTS Consecutive patients (n = 2064) who underwent symptom-limited exercise and dipyridamole stress with gated single-photon emission computed tomography (SPECT) imaging, without early revascularization, were studied. Subsequent cardiac death or nonfatal myocardial infarction was related to exercise and gated SPECT variables. Cox proportional hazards regression modeling was performed to identify predictors of adverse outcome. Annualized event rates in patients with normal and abnormal images were 0.96% and 2.71%, respectively (P < .001). With abnormal imaging, annualized event rates were 0.86% and 3.13% in patients with average to high and fair or poor functional capacity, respectively (P = .019). Abnormal imaging, a severely reduced post-stress ejection fraction, transient ischemic dilation, and fair or poor functional capacity emerged as predictors of adverse outcome. Accordingly, patients were stratified into low-risk, intermediate-risk, and high-risk cohorts with annualized event rates of 0.94%, 2.24%, and 8.19%, respectively (P < .001 in any two-way comparison). CONCLUSIONS A protocol that combines symptom-limited exercise and dipyridamole stress with gated SPECT imaging provides highly effective risk stratification for adverse outcomes.
Collapse
|
15
|
Intermittent ST-segment depressions during adenosine stress test. Clin Nucl Med 2007; 32:927-9. [PMID: 18030042 DOI: 10.1097/rlu.0b013e3181596664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
ST-segment depression during adenosine stress testing is usually a 1-time event during or after the test and is often related to ischemia due to severe 3-vessel disease. In this case report we describe a patient with severe 3-vessel disease who had intermittent ST-segment depression on the electrocardiogram during a myocardial perfusion stress test with adenosine. These intermittent ST depressions could be explained by possible adenosine-induced coronary spasm.
Collapse
|
16
|
Abstract
Nuclear cardiology has made significant advances since the first reports of planar scintigraphy for the evaluation of left ventricular perfusion and function. While the current "state of the art" of gated myocardial perfusion single-photon emission computed tomographic (SPECT) imaging offers invaluable diagnostic and prognostic information for the evaluation of patients with suspected or known coronary artery disease (CAD), advances in the cellular and molecular biology of the cardiovascular system have helped to usher in a new modality in nuclear cardiology, namely, molecular imaging. In this review, we will discuss the current state of the art in nuclear cardiology, which includes SPECT and positron emission tomographic evaluation of myocardial perfusion, evaluation of left ventricular function by gated myocardial perfusion SPECT and gated blood pool SPECT, and the evaluation of myocardial viability with PET and SPECT methods. In addition, we will discuss the future of nuclear cardiology and the role that molecular imaging will play in the early detection of CAD at the level of the vulnerable plaque, the evaluation of cardiac remodeling, and monitoring of important new therapies including gene therapy and stem cell therapy.
Collapse
|
17
|
Johansen A, Høilund-Carlsen PF, Vach W, Christensen HW, Møldrup M, Haghfelt T. To what degree is amelioration of angina following coronary revascularization associated with improvement in myocardial perfusion? Clin Physiol Funct Imaging 2006; 26:263-70. [PMID: 16939502 DOI: 10.1111/j.1475-097x.2006.00685.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To examine the association between changes in chest pain and changes in perfusion following revascularization as assessed by clinical evaluation and myocardial perfusion imaging (MPI) in patients with stable angina. DESIGN In a prospective series of 380 patients (58.8 +/- 8.8 years) referred to angiography because of known or suspected stable angina, changes in chest discomfort and changes in perfusion after 2 years were assessed in 144 patients, who underwent revascularization, and 236, who did not. The decision to treat invasively was made without knowledge of the result of MPI. RESULTS In revascularized patients, the presence of typical/atypical angina was reduced from 93% to 36% and the improvement was associated with improvement in perfusion. A small improvement in perfusion induced a high frequency of change from angina to no pain, whereas a further reduction caused little extra change. In non-revascularized patients the change in chest discomfort was not related to changes in perfusion, which were rarely present. CONCLUSION Alleviation of chest discomfort 2 years after revascularization is associated with improvements in perfusion. This association appeared to be an all-or-nothing phenomenon. Non-revascularized patients also exhibited improvements in chest discomfort despite insignificant changes in perfusion.
Collapse
Affiliation(s)
- Allan Johansen
- Department of Nuclear Medicine, Odense University Hospital, Odense, Denmark.
| | | | | | | | | | | |
Collapse
|
18
|
George RT, Silva C, Cordeiro MAS, DiPaula A, Thompson DR, McCarthy WF, Ichihara T, Lima JAC, Lardo AC. Multidetector computed tomography myocardial perfusion imaging during adenosine stress. J Am Coll Cardiol 2006; 48:153-60. [PMID: 16814661 DOI: 10.1016/j.jacc.2006.04.014] [Citation(s) in RCA: 186] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2005] [Revised: 02/28/2006] [Accepted: 03/08/2006] [Indexed: 10/24/2022]
Abstract
OBJECTIVES The purpose of this study is to validate the accuracy of multidetector computed tomography (MDCT) to measure differences in regional myocardial perfusion during adenosine stress in a canine model of left anterior descending (LAD) artery stenosis, during first-pass, contrast-enhanced helical MDCT. BACKGROUND Myocardial perfusion imaging by MDCT may have significant implications in the diagnosis and treatment of coronary artery disease. METHODS Eight dogs were prepared with a LAD stenosis, and contrast-enhanced MDCT imaging was performed 5 min into adenosine infusion (0.14 to 0.21 mg/kg/min). Images were analyzed using a semiautomated approach to define the regional signal density (SD) ratio (myocardial SD/left ventricular blood pool SD) in stenosed and remote territories, and then compared with microsphere myocardial blood flow (MBF) measurements. RESULTS Mean MBF in stenosed versus remote territories was 1.37 +/- 0.46 ml/g/min and 1.29 +/- 0.48 ml/g/min at baseline (p = NS) and 2.54 +/- 0.93 ml/g/min and 8.94 +/- 5.74 ml/g/min during adenosine infusion, respectively (p < 0.05). Myocardial SD was 92.3 +/- 39.5 HU in stenosed versus 180.4 +/- 41.9 HU in remote territories (p < 0.001). There was a significant linear association of the SD ratio with MBF in the stenosed territory (R = 0.98, p = 0.001) and between regional myocardial SD ratio and MBF <8 ml/g/min, slope = 0.035, SE = 0.007, p < 0.0001. Overall, there was a significant non-linear relationship over the range of flows studied (LR chi-square [2 degrees of freedom] = 31.8, p < 0.0001). CONCLUSIONS Adenosine-augmented MDCT myocardial perfusion imaging provides semiquantitative measurements of myocardial perfusion during first-pass MDCT imaging in a canine model of LAD stenosis.
Collapse
Affiliation(s)
- Richard T George
- Department of Medicine, Division of Cardiology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
19
|
Chow BJW, Beanlands RS, Lee A, DaSilva JN, deKemp RA, Alkahtani A, Ruddy TD. Treadmill Exercise Produces Larger Perfusion Defects Than Dipyridamole Stress N-13 Ammonia Positron Emission Tomography. J Am Coll Cardiol 2006; 47:411-6. [PMID: 16412870 DOI: 10.1016/j.jacc.2005.09.027] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2005] [Revised: 08/30/2005] [Accepted: 09/08/2005] [Indexed: 11/22/2022]
Abstract
OBJECTIVES The aim of this study was to compare treadmill exercise (TEX) and dipyridamole stress on the uptake and retention of N-13 ammonia. BACKGROUND Size and severity of stress-induced myocardial perfusion defects are clinically important. Because ammonia uptake and retention seems to be related to perfusion, viability, and metabolism, exercise stress might induce larger perfusion defects than dipyridamole stress. METHODS Twenty-six patients underwent TEX and dipyridamole stress N-13 ammonia positron emission tomography (PET). Images were assessed with a 17-segment model and a five-point score. Summed stress score (SSS), summed rest score (SRS), and summed difference score (SDS) were calculated. Left ventricular (LV) defect sizes were measured quantitatively with a 70% threshold for abnormal perfusion. RESULTS Compared with dipyridamole stress, TEX yielded larger SSS (9.1 +/- 5.7 vs. 6.9 +/- 5.9; p < 0.01), SDS (5.8 +/- 4.7 vs. 3.7 +/- 4.6; p < 0.02), and percentage of LV stress defect (19.3 +/- 11.5% vs. 13.8 +/- 13.6%; p < 0.02). CONCLUSIONS In patients achieving adequate exercise, TEX N-13 ammonia PET myocardial perfusion imaging (MPI) yields larger stress perfusion defects than dipyridamole stress and might reflect the true myocardial ischemic burden. Treadmill exercise might be the preferred method of stress for routine N-13 ammonia PET MPI.
Collapse
Affiliation(s)
- Benjamin J W Chow
- Division of Cardiology, University of Ottawa Heart Institute, Ottawa, Ontario, Canada.
| | | | | | | | | | | | | |
Collapse
|
20
|
Hendel RC, Bateman TM, Cerqueira MD, Iskandrian AE, Leppo JA, Blackburn B, Mahmarian JJ. Initial clinical experience with regadenoson, a novel selective A2A agonist for pharmacologic stress single-photon emission computed tomography myocardial perfusion imaging. J Am Coll Cardiol 2005; 46:2069-75. [PMID: 16325044 DOI: 10.1016/j.jacc.2005.05.097] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2005] [Revised: 04/24/2005] [Accepted: 05/18/2005] [Indexed: 11/20/2022]
Abstract
OBJECTIVES Regadenoson, a selective A2A adenosine receptor agonist, was evaluated for tolerability and effectiveness as a pharmacological stress agent for detecting reversible myocardial hypoperfusion when combined with single-photon emission computed tomography (SPECT). BACKGROUND Adenosine and dipyridamole are nonselective adenosine agonists currently used as pharmacologic stressors. Despite proven safety, these agents often cause undesirable side effects and require a continuous infusion. METHODS This Phase II, multicenter, open-label trial was conducted in 36 patients who had demonstrated ischemia on a 6-min adenosine SPECT imaging study within the previous 2 to 46 days. Patients received regadenoson as a rapid intravenous bolus dose of 400 microg (n = 18) or 500 microg (n = 18). The radiopharmaceutical was then delivered within one minute. The SPECT images were acquired in a standard manner and uniformly processed at a central laboratory. Regadenoson and adenosine studies were presented in random order and interpreted blindly with a 17-segment model by three observers. Additionally, quantitative analysis was performed with 4D-MSPECT software (University of Michigan, Ann Arbor, Michigan). RESULTS Overall agreement for the presence of reversible hypoperfusion was 86%. The 400-mug dose was better tolerated. Overall, regadenoson was well-tolerated; side effects (e.g., chest discomfort, flushing, dyspnea) were generally mild in severity and self-limiting. High-grade atrioventricular block and bronchospasm were not observed. CONCLUSIONS Regadenoson is well-tolerated and seems as effective as adenosine for detecting and quantifying the extent of hypoperfusion observed with SPECT perfusion imaging. Phase III clinical trials are now underway, given the promise of regadenoson's reduced side effects and simplicity of bolus administration.
Collapse
|
21
|
Sakuma H, Suzawa N, Ichikawa Y, Makino K, Hirano T, Kitagawa K, Takeda K. Diagnostic accuracy of stress first-pass contrast-enhanced myocardial perfusion MRI compared with stress myocardial perfusion scintigraphy. AJR Am J Roentgenol 2005; 185:95-102. [PMID: 15972407 DOI: 10.2214/ajr.185.1.01850095] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE The purpose of this study was to determine the diagnostic accuracy of stress perfusion MRI acquired with saturation-recovery prepared turbo fast low-angle shot (turbo FLASH) compared with stress myocardial perfusion scintigraphy. Recent studies show that first-pass contrast-enhanced myocardial perfusion MRI can provide noninvasive detection of low-limiting stenosis in the coronary artery. MATERIALS AND METHODS First-pass contrast-enhanced MR images were acquired at rest and during stress in 40 patients with suspected coronary artery disease. All patients underwent thallium-201 SPECT without attenuation correction and coronary angiography. Two reviewers independently assigned one of five confidence grades without knowing the results of coronary angiography for receiver operating characteristic (ROC) analysis. Luminal stenosis >70% on coronary angiography was used as a reference standard. RESULTS On coronary angiography, 70% or greater diameter stenosis of the coronary artery was observed in 21 (52.5%) of 40 patients. The areas under the ROC curve for detection of significant stenosis in the individual coronary artery were 0.86 (observer 1) and 0.84 (observer 2) for MRI. These values were 0.79 (observer 1, p = not significant) and 0.72 (observer 2, p = not significant) for 201Tl SPECT. CONCLUSION The diagnostic accuracy of stress perfusion MRI acquired with saturation-recovery-prepared turbo FLASH was comparable with that of stress 201Tl SPECT. Stress first-pass contrast-enhanced MRI is a noninvasive technique that can be used as an alternative to stress myocardial perfusion scintigraphy.
Collapse
Affiliation(s)
- Hajime Sakuma
- Department of Radiology, Mie University Hospital, 2-174 Edobashi, Tsu, Mie 514-8507, Japan.
| | | | | | | | | | | | | |
Collapse
|
22
|
Mishra RK, Dorbala S, Logsetty G, Hassan A, Heinonen T, Schelbert HR, Di Carli MF. Quantitative relation between hemodynamic changes during intravenous adenosine infusion and the magnitude of coronary hyperemia: implications for myocardial perfusion imaging. J Am Coll Cardiol 2005; 45:553-8. [PMID: 15708703 DOI: 10.1016/j.jacc.2004.10.064] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2004] [Revised: 10/20/2004] [Accepted: 10/26/2004] [Indexed: 11/18/2022]
Abstract
OBJECTIVES The goal of this study was to determine the relationship between changes in cardiac hemodynamics during intravenous adenosine (ADO) infusion, and myocardial blood flow (MBF). BACKGROUND The relationship between changes in MBF and the peripheral hemodynamic effects during peak adenosine infusion is unknown. METHODS We studied 348 (age 57 +/- 11 years; 106 females) without evidence of obstructive coronary artery disease by positron emission tomography (PET). Patients underwent [(13)N]ammonia PET imaging to measure MBF and coronary vascular resistance (CVR) at rest and during a standard 6-min ADO infusion. Changes in heart rate (HR) and mean arterial pressure (MAP) were measured at baseline and during peak hyperemia. RESULTS During ADO, HR increased (delta: 24 +/- 11 beats/min) and MAP decreased (delta: -2 +/- 10 mm Hg). Overall, delta HR correlated poorly with hyperemic MBF (R = 0.10, p = 0.06) and with CVR (R = 0.11, p = 0.04). Delta MAP also showed a weak correlation with hyperemic MBF (R = 0.04, p = 0.44) and with CVR (R = 0.11, p = 0.04). Patients in the lowest tertile for delta HR showed a 7% lower hyperemic MBF (1.84 +/- 0.6 ml/min/g vs. 1.98 +/- 0.6 ml/min/g, p = 0.022) and an 8% higher CVR (54 +/- 20 mm Hg/ml/min/g vs. 50 +/- 17 mm Hg/ml/min/g, p = 0.056) compared with those in the highest tertile. Patients in the lowest tertile for delta MAP (i.e., greatest decline) showed similar hyperemic MBF, and an 8% lower CVR compared with those in the highest tertile (p = NS for both). These small differences between tertiles remain, even after adjusting for differences in age, gender, smoking status, and lipid profile. CONCLUSIONS Changes in cardiac hemodynamics during intravenous ADO are generally poor predictors of changes in MBF and CVR during peak hyperemia, and, thus, they should not be used to assess the effectiveness of vasodilator stress in myocardial perfusion imaging.
Collapse
Affiliation(s)
- Rakesh K Mishra
- Division of Nuclear Medicine, Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | | | | | | | | | | | | |
Collapse
|
23
|
Loong CY, Anagnostopoulos C. Diagnosis of coronary artery disease by radionuclide myocardial perfusion imaging. Heart 2004; 90 Suppl 5:v2-9. [PMID: 15254003 PMCID: PMC1876323 DOI: 10.1136/hrt.2003.013581] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Affiliation(s)
- C Y Loong
- National Heart & Lung Institute, Imperial College London, London, UK
| | | |
Collapse
|
24
|
Ishida N, Sakuma H, Motoyasu M, Okinaka T, Isaka N, Nakano T, Takeda K. Noninfarcted myocardium: correlation between dynamic first-pass contrast-enhanced myocardial MR imaging and quantitative coronary angiography. Radiology 2003; 229:209-16. [PMID: 12944596 DOI: 10.1148/radiol.2291021118] [Citation(s) in RCA: 159] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To determine the accuracy of first-pass contrast material-enhanced stress myocardial magnetic resonance (MR) imaging for depiction of myocardial ischemia in patients without myocardial infarction. MATERIALS AND METHODS First-pass contrast-enhanced MR images of the entire left ventricle were acquired in 104 patients at rest and during dipyridamole-induced stress by using an interleaved notched saturation technique. Coronary angiography was performed in all patients, and stress perfusion single photon emission computed tomography (SPECT) was performed in 69 patients. Receiver operating characteristic curve analysis was performed to compare the diagnostic accuracies of first-pass contrast-enhanced stress MR imaging and stress SPECT, with coronary angiography as the reference standard. RESULTS The overall sensitivity of MR imaging for depicting at least one coronary artery with significant stenosis was 90% (69 of 77 patients). The sensitivities of MR imaging for depiction of single-, double-, and triple-vessel stenoses were 85% (33 of 39 patients), 96% (22 of 23 patients), and 100% (15 of 15 patients), respectively. The specificity of MR imaging for identification of patients with significant coronary artery stenoses was 85% (23 of 27 patients). The areas under the receiver operating characteristic curve for detection of significant stenosis in individual coronary arteries were 0.888 (observer 1) and 0.911 (observer 2) for MR imaging and 0.707 (observer 1, P <.001) and 0.750 (observer 2, P <.001) for SPECT. CONCLUSION In patients without myocardial infarction, stress enhancement at dynamic MR imaging correlates more closely with quantitative coronary angiography results than does stress enhancement at SPECT.
Collapse
Affiliation(s)
- Nanaka Ishida
- Department of Radiology, Mie University School of Medicine, 2-174 Edobashi, Tsu, Mie 514-8507, Japan
| | | | | | | | | | | | | |
Collapse
|
25
|
Masugata H, Peters B, Lafitte S, Strachan GM, Ohmori K, Mizushige K, Kohno M. Assessment of adenosine-induced coronary steal in the setting of coronary occlusion based on the extent of opacification defects by myocardial contrast echocardiography. Angiology 2003; 54:443-8. [PMID: 12934764 DOI: 10.1177/000331970305400408] [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: 11/15/2022]
Abstract
The authors examined the ability of real-time myocardial contrast echocardiography (MCE) to assess adenosine-induced coronary steal in the setting of coronary artery occlusion. The left anterior descending (LAD) coronary artery was occluded in 8 open-chest dogs. Real-time MCE was performed during LAD occlusion, and the extent of opacification defects from MCE was measured without and with adenosine infusion. Microsphere-derived myocardial blood flow (MBF) was measured in the LAD and left circumflex (LCx) coronary artery beds, and the LAD/LCx ratio of MBF was calculated. The LAD/LCx ratio of MBF decreased in response to adenosine administration (without adenosine: 0.66, with adenosine: 0.43, p < 0.01). The extent of opacification defects from MCE increased in response to adenosine administration (without adenosine: 18%, with adenosine: 22%, p < 0.01). Thus, real-time MCE allows for the detection of adenosine-induced coronary steal as changes in the extent of opacification defects in the setting of occlusion of 1 coronary artery accompanying another normally patent coronary artery.
Collapse
Affiliation(s)
- Hisashi Masugata
- Second Department of Internal Medicine, Kagawa Medical University, 1750-1, Miki, Kita, Kagawa 761-0793, Japan.
| | | | | | | | | | | | | |
Collapse
|
26
|
Trochu JN, Zhao G, Post H, Xu X, Belardinelli L, Belloni FL, Hintze TH. Selective A2A adenosine receptor agonist as a coronary vasodilator in conscious dogs: potential for use in myocardial perfusion imaging. J Cardiovasc Pharmacol 2003; 41:132-9. [PMID: 12500031 DOI: 10.1097/00005344-200301000-00017] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The authors sought to demonstrate the advantages of a selective, potent, short-acting A adenosine receptor agonist, CVT-3146 (2-(N-pyrazolyl)Ado derivative), for potential clinical use as a coronary vasodilator during myocardial perfusion imaging. The use of adenosine in a pharmacological stress test during myocardial imaging is limited by side effects mediated by A1 and A2B adenosine receptors and by its ultrashort duration of action. CVT-3146 (0.1-5 microg/kg) and adenosine (13-267 microg/kg) were given as peripheral intravenous injections in 10 awake dogs instrumented for measurement of coronary blood flow (CBF). CVT-3146 caused a dose-dependent increase of CBF (ED50 = 0.34 +/- 0.08 microg/kg, maximal increase = 221 +/- 18%, n = 6). Adenosine was less potent (ED = 51 +/- 15 microg/kg, p < 0.05) but equieffective (maximal increase in CBF = 227 +/- 11%). The increase in CBF caused by 2.5 microg/kg CVT-3146 reached 84 +/- 5% of the maximal reactive hyperemia following 20 s of coronary occlusion (n = 4). After a 10-s injection of CVT-3146 (2.5 microg/kg), the increase in CBF remained at least twofold above baseline for 97 +/- 14 s, whereas for adenosine (267 microg/kg), the twofold increase in CBF lasted only 24 +/- 2 s (p < 0.01, n = 6). A 30-s injection of 2.5 microg/kg CVT-3146 prolonged the twofold increase in CBF up to 221 +/- 20 s. No atrioventricular block was noted. At 2.5 microg/kg, the peak effect of CVT-3146 on CBF was associated with a short-lasting (20 +/- 6 s) increase in heart rate (78 +/- 9 bpm) and decrease in mean arterial blood pressure (13 +/- 6 mm Hg, p < 0.05, n = 6). CVT-3146 is a potent coronary vasodilator. Its short duration of action, minimal and transient systemic hemodynamic effects, and ease of administration may make this agonist suitable for pharmacological coronary vasodilation during myocardial perfusion imaging for noninvasive detection of subcritical arterial stenosis.
Collapse
Affiliation(s)
- Jean-Noël Trochu
- Department of Physiology, New York Medical College, Valhalla, New York 10595, USA
| | | | | | | | | | | | | |
Collapse
|
27
|
Meisner JS, Shirani J, Alaeddini J, Frishman WH. Use of pharmaceuticals in noninvasive cardiovascular diagnosis. HEART DISEASE (HAGERSTOWN, MD.) 2002; 4:315-30. [PMID: 12350244 DOI: 10.1097/00132580-200209000-00008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/19/2023]
Abstract
A number of pharmaceuticals are employed as diagnostic agents for cardiovascular diseases. Four groups of agents are reviewed here: 1) vasoactive substances employed as adjuncts to physical maneuvers in diagnosis of structural heart disease; 2) vasodilators used to produce heterogeneity of coronary flow; 3) sympathomimetic agents simulating the effects of exercise on the heart for the purpose of detection of coronary artery stenosis; and 4) ultrasonic contrast agents used to enhance myocardial imaging for the assessment of segmental wall motion. In the first group are amyl nitrate, a vasodilator, and methoxamine and phenylephrine, both vasopressors. The vasodilators of the second group are dipyridamole and adenosine. When combined with scintigraphic perfusion imaging or with echocardiographic assessment of segmental wall motion, these agents can detect single- or multiple-vessel coronary artery disease with sensitivity and specificity comparable to submaximal exercise. They are especially useful for preoperative risk assessment before noncardiac surgery. The sympathomimetic agents of the third group, dobutamine and arbutamine, increase myocardial contractility and heart rate, and dilate the peripheral vasculature. As with the vasodilators, when combined with nuclear or echocardiographic techniques they are equivalent to exercise in detection of coronary disease. They are especially useful in patients with bronchospastic disease and for assessment of myocardial viability. Agents from groups 2 and 3 have acceptable side-effect and safety profiles. The last group reviewed includes echocardiographic contrast agents that, in this investigative setting, are employed to enhance detection of segmental wall motion when used with agents from groups 2 and 3.
Collapse
Affiliation(s)
- Jay S Meisner
- Department of Medicine, Divisions of Cardiology, Albert Einstein College of Medicine/Montefiore Medical Center, Bronx, New York, USA.
| | | | | | | |
Collapse
|
28
|
|
29
|
Abstract
BACKGROUND Adenosine cardiac stress is widely used as an alternative to exercise testing during myocardial perfusion imaging (MPI). Dyspnea often accompanies the adenosine stress test. Although known asthmatic patients are excluded from this test because of the danger of bronchospasm, there is incomplete information regarding the role of factors such as chronic obstructive pulmonary disease (COPD) and tobacco smoking in adenosine-induced dyspnea. PATIENTS AND METHODS A total of 122 consecutive patients (75 male, 47 female; mean age 59 years, SD 10 years) undergoing pharmacologic stress testing with an intravenous infusion of adenosine also had volume-flow spirometry (Vitalograph Compact, Vitalograph Ltd) before, during, and after the test. The indices assessed were forced expiratory volume in one second, its ratio to the forced vital capacity, and peak expiratory flow rate. RESULTS Mild to severe symptoms were experienced by 81% of patients during adenosine infusion. More than half the patients had dyspnea, but there was no associated bronchospasm. Although the patients with COPD showed parameters indicative of bronchial resistance compared with those without this problem, there was no further deterioration after adenosine infusion. Similarly, patients with a history of tobacco abuse, despite showing a tendency toward increasing airways resistance, had no bronchospasm during the administration of adenosine. CONCLUSIONS (1) Although dyspnea is a common problem during adenosine stress MPI, it is not associated with any appreciable bronchospasm. (2) COPD and tobacco abuse do not appear to be contraindications to adenosine stress MPI studies. However, it is probably safe to exclude patients with severe COPD from adenosine stress MPI until after further evaluation with larger numbers of patients.
Collapse
Affiliation(s)
- K K Balan
- Department of Nuclear Medicine, Royal Liverpool University Hospital, Liverpool, United Kingdom.
| | | |
Collapse
|
30
|
O'Rourke RA. Optimal medical management of patients with chronic ischemic heart disease. Dis Mon 2001; 47:154-96. [PMID: 11398098 DOI: 10.1016/s0011-5029(01)90012-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
31
|
O'Rourke RA. Optimal medical management of patients with chronic ischemic heart disease. Curr Probl Cardiol 2001; 26:189-238. [PMID: 11305088 DOI: 10.1067/mcd.2001.114141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- R A O'Rourke
- Division of Cardiology, Department of Medicine, University of Texas Health Science Center, San Antonio, Texas, USA
| |
Collapse
|
32
|
Yao SS, Rozanski A. Principal uses of myocardial perfusion scintigraphy in the management of patients with known or suspected coronary artery disease. Prog Cardiovasc Dis 2001; 43:281-302. [PMID: 11235845 DOI: 10.1053/pcad.2001.20466] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The use of myocardial perfusion single photon emission computed tomography (SPECT) has undergone considerable expansion and evolution over the past 2 decades. Although myocardial perfusion imaging was first conceived as a noninvasive diagnostic tool for determining the presence or absence of coronary artery disease, its prognostic value is now well established. Thus, identification of patients at risk for future cardiac events has become a primary objective in the noninvasive evaluation of patients with chest pain syndromes and among patients with known coronary artery disease. In particular, the ability of myocardial perfusion SPECT to identify patients at low (< 1%), intermediate (1% to 5%) or high (> 5%) risk for future cardiac events is essential to patient management decisions. Moreover, previous studies have conclusively shown the incremental prognostic value of myocardial perfusion SPECT over clinical and treadmill exercise data in predicting future cardiac events. This report addresses the current role and new developments, with respect to the use of myocardial perfusion imaging, in determining patient risk for cardiac events and the cost-effective integration of such information into patient management decisions.
Collapse
Affiliation(s)
- S S Yao
- Department of Medicine, St Luke's-Roosevelt Hospital Center, Columbia University College of Physicians and Surgeons, New York, NY 10019, USA
| | | |
Collapse
|
33
|
Uematsu T, Kozawa O, Matsuno H, Niwa M, Yoshikoshi H, Oh-uchi M, Kohno K, Nagashima S, Kanamaru M. Pharmacokinetics and tolerability of intravenous infusion of adenosine (SUNY4001) in healthy volunteers. Br J Clin Pharmacol 2000; 50:177-81. [PMID: 10930971 PMCID: PMC2014395 DOI: 10.1046/j.1365-2125.2000.00214.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AIMS To examine the tolerability and disposition of i.v. adenosine (SUNY4001) in healthy male Japanese volunteers. METHODS SUNY4001 was infused i.v. for 6 min at 0 (placebo), 60, 100, 120 and 140 microg kg-1 min-1 in a dose-escalating manner in 30 healthy subjects. Adenosine and its metabolites were determined in the plasma and urine. RESULTS Only plasma hypoxanthine was increased from 3 min during until 5-10 min after SUNY4001 infusion at the higher rates without any significant dose-related changes in plasma adenosine, inosine, xanthine or uric acid, or in urinary adenosine and all metabolites compared with the placebo. There was a dose-related increase in the incidence of subjective symptoms such as heat sensation, flushed face, dyspnoea, chest discomfort, etc. Transient and self-subsiding episodes of second-degree atrioventricular block were found in two subjects each at the higher doses. CONCLUSIONS Adenosine infusion at < or = 140 microg kg-1 min-1 was concluded to be generally well tolerated.
Collapse
Affiliation(s)
- T Uematsu
- Department of Pharmacology, Gifu University School of Medicine, Gifu 500-8705, Japan.
| | | | | | | | | | | | | | | | | |
Collapse
|
34
|
He ZX, Cwajg E, Hwang W, Hartley CJ, Funk E, Michael LH, Verani MS. Myocardial blood flow and myocardial uptake of (201)Tl and (99m)Tc-sestamibi during coronary vasodilation induced by CGS-21680, a selective adenosine A(2A) receptor agonist. Circulation 2000; 102:438-44. [PMID: 10908217 DOI: 10.1161/01.cir.102.4.438] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND We investigated the hemodynamic and coronary vasodilatory effects of CGS-21680, a potent selective adenosine A(2A) agonist, as well as its potential use as a new stress modality in combination with perfusion scintigraphy. METHODS AND RESULTS A stenosis of the left anterior descending coronary artery (LAD) was produced in dogs to reduce the reactive hyperemic response to <20%. Adenosine and CGS-21680 were then separately infused to maximize left circumflex coronary artery (LCx) flow velocity. (201)Tl (0.5 mCi) and (99m)Tc-sestamibi (5 mCi) were injected at the maximal dose of CGS-21680. Heart rate decreased with adenosine but increased during CGS-21680 infusion (P<0.005). The decrease in systolic blood pressure was more prominent with adenosine than with CGS-21680 (P<0.005). In the control LCx zone, maximal myocardial blood flow (MBF) (measured by radioactive microspheres) increased 3.1-fold during adenosine infusion (P<0.005) and 3.8-fold during CGS-21680 infusion (P<0.005). In the stenotic LAD zone, MBF did not change significantly. During adenosine and CGS-21680 infusion, stenosis/control zone MBF ratios were comparable (0.32+/-0.11 versus 0.27+/-0.10, P=NS), and transmural (201)Tl and (99m)Tc-sestamibi count-activity ratios (0.48+/-0.11 and 0.51+/-0.09, respectively) were also comparable (P=NS). Myocardial scintigraphy uncovered perfusion defects in all dogs. CONCLUSIONS CGS-21680 elicits coronary vasodilation comparable to that of adenosine and produces profound heterogeneity of MBF and of (201)Tl and (99m)Tc-sestamibi myocardial uptake, rendering it a promising agent for pharmacological myocardial perfusion imaging.
Collapse
Affiliation(s)
- Z X He
- Section of Cardiology, Baylor College of Medicine/Methodist Hospital, Houston, Tex, USA
| | | | | | | | | | | | | |
Collapse
|
35
|
Kurata C, Uehara A, Sugi T, Yamazaki K, Tawarahara K, Mikami T, Matoh F, Odagiri K. Exercise myocardial perfusion scintigraphy is useful for evaluating myocardial ischemia even in the elderly. Ann Nucl Med 2000; 14:181-6. [PMID: 10921482 DOI: 10.1007/bf02987857] [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: 10/21/2022]
Abstract
Pharmacologic stress testing is recommended to elderly patients as a valuable alternative to exercise testing. We examined whether exercise testing is as useful for evaluating myocardial ischemia in the elderly as in the young. The consecutive 1,508 patients who underwent exercise 201Tl single-photon emission computed tomography (SPECT) were divided into six age groups: 6-29 years (n = 56), 30-44 (n = 143), 45-54 (n = 311), 55-64 (n = 498), 65-74 (n = 402), and 75-88 (n = 98). Both heart rate and rate-pressure product at peak exercise were significantly lower in patients aged 75-88 than in the other five groups. The frequency of ischemic ST depression was higher in patients aged 75-88 than in those aged 6-74, although the difference was not significant. Moreover, the frequency of 201Tl transient defect was significantly higher in patients aged 75-88 than in those aged 6-74. On the other hand, the sensitivity of ischemic ST depression for 201Tl transient defect was similar among the six groups, but the specificity was significantly lower in patients aged 75-88 than in those aged 6-74. In conclusion, exercise 201Tl SPECT is useful for evaluating myocardial ischemia even in the elderly, but exercise electrocardiography has limitations such as lower specificity in the elderly than 201Tl SPECT.
Collapse
Affiliation(s)
- C Kurata
- Department of Medicine II, Hamamatsu University School of Medicine, Japan.
| | | | | | | | | | | | | | | |
Collapse
|
36
|
Candell Riera J, Castell Conesa J, Jurado López J, López De Sá E, Nuño de la Rosa JA, Ortigosa Aso FJ, Valle Tudela VV. [Nuclear cardiology: technical bases and clinical applications]. REVISTA ESPANOLA DE MEDICINA NUCLEAR 2000; 19:29-64. [PMID: 10758435 DOI: 10.1016/s0212-6982(00)71866-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Although the role of nuclear cardiology is currently well consolidated, the addition of new radiotracers and modern techniques makes it necessary to continuously update the requirements, equipment and clinical applications of these isotopic tests. The characteristics of the radioisotopic drugs and examinations presently used are explained in the first part of this text. In the second, the indications of them in diagnostic and prognostic evaluation of the different coronary diseases are presented.
Collapse
Affiliation(s)
- J Candell Riera
- Servicio de Cardiología, Hospital General Universitari Vall d'Hebron, Barcelona, 08035, España.
| | | | | | | | | | | | | |
Collapse
|
37
|
Abstract
Pharmacological stress in conjunction with radionuclide myocardial perfusion imaging has become a widely used noninvasive method of assessing patients with known or suspected coronary artery disease. In the United States, over one third of perfusion imaging studies are performed with pharmacological stress. Pharmacological stress agents fall into two categories: coronary vasodilating agents such as dipyridamole and adenosine, and cardiac positive inotropic agents such as dobutamine and arbutamine. For both, in the presence of coronary artery disease (CAD), perfusion image abnormalities result from heterogeneity of coronary blood flow reserve. Vasodilating agents work directly on the coronary vessels to increase blood flow, whereas inotropic agents work indirectly by increasing myocardial work load, which then leads to an increase in coronary blood flow. Both classes of agents have high accuracies for diagnosing coronary artery disease, and they have excellent safety records with acceptably low occurrences of side effects. For dipyridamole planar thallium imaging, pooled analysis yields a sensitivity of 85% and a specificity of 87% for diagnosis of coronary disease, but there is a large variation in reported values depending on various factors, such as the extent of postcatheterization referral bias, the type of imaging (planar versus single photon emission computed tomography [SPECT]), the types of patients being studied (single versus multivessel disease, men versus women), and the imaging agent used (thallium versus one of the technetium-based agents). Diagnostic accuracies for adenosine are similar to those of dipyridamole, with reported overall sensitivities ranging from 83% to 97%, and specificities ranging from 38% to 94%. For dobutamine, pooled analyses yield a sensitivity of 82% and a specificity of 75%. There is some concern that dobutamine may interfere with uptake of technetium-99m sestamibi, lowering the sensitivity for detection of disease, and thus the vasdodilating agents are generally preferred. Pharmacological stress testing has high clinical use for risk stratifying patients with known or suspected CAD, in patients after myocardial infarction, and in patients needing noncardiac surgery. Vasodilating agents are particularly advantageous in assessing post-myocardial infarction patients, allowing testing as soon as 2 days after the event. Like patients undergoing exercise stress testing, patients with normal perfusion images by pharmacological stress have a <1% annual incidence of cardiac events. The likelihood of an event increases with the extent and severity of perfusion abnormalities. However, it is important to consider clinical variables when using perfusion imaging for risk stratification, particularly in the presurgery patients. As with exercise testing, adjunct markers such as ST segment depression during testing, lung uptake of radiotracer (if thallium is used), and ventricular cavity dilatation add additional prognostic information to that available from the perfusion images alone. The aim of current research is to find better agents that are easier to use and that have fewer side effects. MRE-0470 is an experimental vasodilating agent that is more receptor selective than adenosine and promises a lower incidence of hypotension. Arbutamine more closely simulates exercise than dobutamine, and it can be administered by a closed-loop computerized delivery device. Work is also underway to look at novel uses of pharmacological stress agents, such as acquiring gated SPECT images during dobutamine infusion to enhance detection of myocardial viability. With increasing use of noninvasive testing in elderly patients and in patients with comorbidities that preclude adequate exercise, pharmacological stress testing has become an indispensable tool for radionuclide myocardial perfusion imaging studies. A good understanding of pharmacological stress testing is essential for performing high-quality nuclear cardiology
Collapse
Affiliation(s)
- M I Travain
- Department of Nuclear Medicine, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, NY 10467-2490, USA
| | | |
Collapse
|
38
|
Abstract
The principle application of stress testing is the detection of myocardial ischemia in patients suspected of having coronary artery disease. Stress testing is also used to assess physical exercise capacity in normal controls and patients with various types of heart disease, such as cardiomyopathy and valvular disease. The various choices of stress modalities are discussed in this article.
Collapse
Affiliation(s)
- M H Crawford
- Division of Cardiology, University of New Mexico School of Medicine, Albuquerque, USA
| |
Collapse
|
39
|
Kim Y, Goto H, Kobayashi K, Sawada Y, Miyake Y, Fujiwara G, Okada T, Nishimura T. A new method to evaluate ischemic heart disease: combined use of rest thallium-201 myocardial SPECT and Tc-99m exercise tetrofosmin first pass and myocardial SPECT. Ann Nucl Med 1999; 13:147-53. [PMID: 10435374 DOI: 10.1007/bf03164854] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
We developed a new diagnostic method for simultaneously evaluating myocardial ischemia, myocardial viability and ventricular function in less than 90 minutes by combined use of rest thallium-201 (Tl) SPECT and exercise Tc-99m tetrofosmin (TF) first pass and SPECT. The subjects were 9 healthy controls, 19 angina pectoris patients, and 19 old myocardial infarction patients, in all of whom coronary angiography had been performed. Rest Tl myocardial SPECT was performed first, and was followed by exercise TF myocardial SPECT. We also performed first pass radionuclide angiography by TF during maximum exercise on a bicycle ergometer to assess the left ventricular ejection fraction (LVEF). The total examination time was less than 90 minutes. SPECT diagnosis was performed by semi-quantitative analysis. LVEF below 55% was regarded as abnormal. In the patients with angina pectoris, analysis according to the coronary artery showed that the diagnostic accuracy of SPECT was 85.0% for ischemia in the region of the left anterior descending branch (LAD), 87.5% for the left circumflex branch (LCX) and 77.8% for the right coronary artery (RCA). The accuracy of diagnosis for angina pectoris was 82.1%, as determined by SPECT alone, and rose to 89.3% when the LVEF levels were also taken into consideration. In the patients with old myocardial infarction, the diagnostic accuracy of SPECT was 84.2% for the LAD, 92.3% for the LCX and 85.0% for the RCA. Analysis by patients showed that the accuracy of diagnosis for myocardial infarction was 85.7%, as determined by SPECT alone. The diagnostic accuracy, however, rose to 89.3% when the LVEF levels also were taken into consideration. In conclusion, it was demonstrated that this combined diagnostic method was highly reliable for evaluating ischemic heart disease within a short time.
Collapse
Affiliation(s)
- Y Kim
- Department of Internal Medicine, Nishiyodo Hospital, Japan
| | | | | | | | | | | | | | | |
Collapse
|
40
|
Gibbons RJ, Chatterjee K, Daley J, Douglas JS, Fihn SD, Gardin JM, Grunwald MA, Levy D, Lytle BW, O'Rourke RA, Schafer WP, Williams SV, Ritchie JL, Cheitlin MD, Eagle KA, Gardner TJ, Garson A, Russell RO, Ryan TJ, Smith SC. ACC/AHA/ACP-ASIM guidelines for the management of patients with chronic stable angina: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Committee on Management of Patients With Chronic Stable Angina). J Am Coll Cardiol 1999; 33:2092-197. [PMID: 10362225 DOI: 10.1016/s0735-1097(99)00150-3] [Citation(s) in RCA: 367] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
41
|
Guías de actuación clínica de la Sociedad Española de Cardiología. Cardiología nuclear: bases técnicas y aplicaciones clínicas. Rev Esp Cardiol 1999. [DOI: 10.1016/s0300-8932(99)75025-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
42
|
Valik D, Jones JD. Hereditary disorders of purine and pyrimidine metabolism: identification of their biochemical phenotypes in the clinical laboratory. Mayo Clin Proc 1997; 72:719-25. [PMID: 9276598 DOI: 10.1016/s0025-6196(11)63590-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
OBJECTIVE To describe a laboratory approach to the diagnosis of hereditary diseases of purine and pyrimidine metabolism and emphasize clinical situations in which these disorders should be considered in the differential diagnosis. DESIGN Disease-specific patterns were identified in random specimens of ultrafiltered urine by using gradient high-performance liquid chromatography with diode-array detection, and reference ranges were established for uric acid, hypoxanthine, xanthine, and uracil expressed per creatinine in random specimens of urine. MATERIAL AND METHODS Diagnostically significant purines and pyrimidines were separated with use of a Supelco LC-18-S nucleoside column eluted with 25 mmol/L ammonium acetate buffer and acetonitrile-methanol-water. Biologic fluids were prepared by ultrafiltration after addition of 3-methyluridine as internal standard. We used specimens negative for screening of metabolic disorders to establish reference ranges. RESULTS Disease-specific patterns were identified in specimens with purine and pyrimidine disorders and several urea cycle disorders characterized by increased production of pyrimidine. CONCLUSION The approach described identified disease-specific patterns of purine and pyrimidine disorders and several urea cycle disorders. We suggest that testing for purine and pyrimidine disorders be done in specimens evaluated in metabolic laboratories for "screening for inborn errors of metabolism."
Collapse
Affiliation(s)
- D Valik
- Division of Clinical Biochemistry and Immunology, Mayo Clinic Rochester, Minnesota 55905, USA
| | | |
Collapse
|
43
|
Affiliation(s)
- F A Chaudhry
- Department of Medicine, Allegheny University of the Health Sciences, Philadelphia, Pennsylvania 19102, USA
| |
Collapse
|
44
|
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.
Collapse
Affiliation(s)
- A F Khoury
- Department of Internal Medicine, Baylor College of Medicine, Houston, Texas, USA
| | | | | | | |
Collapse
|
45
|
Versaci F, Tomai F, Nudi F, Gaspardone A, De Fazio A, Ciavolella M, Crea F, Mango L, Chiariello L, Gioffrè PA. Differences of regional coronary flow reserve assessed by adenosine thallium-201 scintigraphy early and six months after successful percutaneous transluminal coronary angioplasty or stent implantation. Am J Cardiol 1996; 78:1097-102. [PMID: 8914870 DOI: 10.1016/s0002-9149(96)90059-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
This study assesses regional coronary flow reserve using adenosine thallium-201 scintigraphy early and 6 months after angiographically successful percutaneous transluminal coronary angioplasty (PTCA) or stent implantation. Seventeen consecutive men with a significant isolated left anterior descending coronary artery stenosis were scheduled for repeat coronary angiography and adenosine-planar thallium-201 scintigraphy within 24 hours and 6 months after successful PTCA (n = 8) or stent implantation (n = 9). After background subtraction, left ventricular segmental uptake was semiquantitatively assessed on thallium images. The perfusion defect severity was scored from 0 (normal) to 3. Coronary angiograms were analyzed using an automated edge contour detection computer analysis system. Data are expressed as mean value +/- 1 SD, and proportions as percentage. The residual narrowing was 17 +/- 8% after PTCA and 9 +/- 2% after stent implantation (p = 0.02). Twenty-four hours after the procedure, hypoperfused segments were detected in all patients (100%) and in 4 patients (44%) (p = 0.05), respectively. The total number of hypoperfused segments was greater after PTCA than after stent implantation (16 [40%] vs 7 [16%], p = 0.001, respectively) as was the perfusion defect severity (4.4 +/- 3.1 vs 1 +/- 1.2, p = 0.006). Six months after the procedure, 3 of the 5 patients who had undergone PTCA without restenosis still had reversible perfusion defects. None of the stent-treated patients had restenosis or reversible perfusion defects (p = 0.05). Among PTCA-treated patients without restenosis, the total number of hypoperfused segments and the perfusion defect severity were 9 of 25 (36%) and 0.8 +/- 0.8, respectively. Thus, a regional reduction in coronary flow reserve, occasionally observed early after successful stent implantation, is probably due to a transient alteration of small coronary vessels, as was also supported by the absence of perfusion defects 6 months after the procedure. The more severe impairment of regional coronary flow reserve observed early after successful PTCA is probably also due to angiographic underestimation of the residual stenosis, as suggested also by the persistence of reversible perfusion defects 6 months after the procedure in a few patients.
Collapse
Affiliation(s)
- F Versaci
- Servizio Speciale di Diagnosi e Cura di Emodinamica, Divizione di Cardiochiurgia, Università di Roma Tor Vergata, Italy
| | | | | | | | | | | | | | | | | | | |
Collapse
|
46
|
Abstract
Successful scintigraphic imaging of coronary artery stenosis is dependent on detecting regional differences (nonhomogeneous distribution) in coronary blood flow that can be induced by physiologic or pharmacologic stress. Table 1 represents a summary of major pharmacologic responses of the heart to the four agents discussed above. Both adenosine and dipyridamole produce superior coronary vasodilation and tend to be preferred for use in single-photon emission computed tomography, whereas dobutamine and arbutamine provoke a marked ischemic response and tend to be preferred for use in echocardiography. Which agent employed remains a judgment of the physician based on known side effects of these agents, the patient's ability to tolerate these side effects, and the nature of the test desired.
Collapse
Affiliation(s)
- C Orlandi
- Medco Research, Inc., Research Triangle Park, NC 27709, USA
| |
Collapse
|
47
|
Abstract
In choosing a pharmacologic agent for stress testing, the clinician must keep a number of things in mind, such as the diagnostic utility of the agent or in what situations a vasodilator or catecholamine will be the better choice. Although all stress agents produce similar diagnostic accuracy for CAD, vasodilators have a higher cardiac uptake than catecholamines, and the addition of exercise improves the heart/background contrast ratios. With regard to physiologic comparisons, exercise or dobutamine will double coronary perfusion compared with baseline flow, but vasodilators produce a threefold or fourfold increase. The clinician should also keep in mind that adenosine will produce the shortest duration of hyperemia, whereas dobutamine and arbutamine produce a longer effect, and dipyridamole has the longest duration. If electrophysiologic considerations are important, exercise and catecholamines accelerate sinoatrial and atrioventricular conduction and are not typically associated with heart block. In contrast, adenosine can cause transient atrioventricular block, but this rarely occurs with dipyridamole. Clinical factors also must be considered. Although clinical utility of pharmacologic stress agents in the first 24 hours after infarction has not been demonstrated, the prognostic utility of vasodilators in the subsequent 2- to 4-day period has been shown. With patients with pulmonary disease (asthma) who do not have wheezing, dipyridamole can be used, but dobutamine or arbutamine should be used in patients with recent respiratory failure or bronchospasm before testing. In patients with left bundle branch block, vasodilators are the preferred stress agents rather than synthetic catecholamines or dynamic exercise. In the first crossover thallium imaging, there was good overall agreement in segmental perfusion comparing adenosine and dipyridamole, but there was a tendency for adenosine to detect more ischemia. The clinical significance (if any) for these findings has yet to be determined.
Collapse
Affiliation(s)
- J A Leppo
- Department of Nuclear Medicine, University of Massachusetts Medical Center, Worcester 01655-0243, USA
| |
Collapse
|
48
|
Glover DK, Ruiz M, Yang JY, Koplan BA, Allen TR, Smith WH, Watson DD, Barrett RJ, Beller GA. Pharmacological stress thallium scintigraphy with 2-cyclohexylmethylidenehydrazinoadenosine (WRC-0470). A novel, short-acting adenosine A2A receptor agonist. Circulation 1996; 94:1726-32. [PMID: 8840867 DOI: 10.1161/01.cir.94.7.1726] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
BACKGROUND Pharmacological stress imaging with adenosine or dipyridamole is associated with a high incidence of side effects, including hypotension, chest pain, AV conduction abnormalities, and bronchospasm. Although the desired coronary vasodilatory response is mediated primarily by the adenosine A2A receptors, these side effects result from stimulation of the A1, A2B, or A3 adenosine receptors. We hypothesized that a selective adenosine A2A receptor agonist would induce coronary vasodilatation appropriate for pharmacological stress imaging, without evoking adenosine receptor-mediated side effects. METHODS AND RESULTS Infusions of a potent and selective A2A adenosine receptor agonist, WRC-0470 (0.1 to 3 micrograms kg-1. min-1 for 10 minutes), to five open-chest dogs produced dose-related left anterior descending (LAD) and left circumflex (LCx) coronary artery vasodilatation without altering mean arterial pressure, heart rate, left atrial pressure, or left ventricular dP/dt. In the same dogs, adenosine (300 micrograms . kg-1. min-1 for 4 minutes) produced coronary vasodilatation that was limited by significant hypotension. To determine the utility of WRC-0470 for pharmacological stress imaging, the hemodynamic responses to WRC-0470 (0.6 microgram.kg-1.min-1 for 10 minutes) and adenosine (250 micrograms.kg-1.min-1 for 4 minutes) were compared in dogs with critical LAD stenoses. 201T1 was injected at the peak WRC-0470 stress response. WRC-0470 increased LCx flow nearly fivefold but did not significantly lower mean arterial pressure. Anteroseptal defects were readily apparent in slice images from all dogs. The mean defect ratio (LAD/LCx) was 0.59 +/- 0.06. CONCLUSIONS The potent A2A-selective adenosine receptor agonist WRC-0470 is a short-acting coronary vasodilator with potential utility for pharmacological stress perfusion imaging.
Collapse
Affiliation(s)
- D K Glover
- Department of Medicine, University of Virginia Health Sciences Center, Charlottesville 22908, USA.
| | | | | | | | | | | | | | | | | |
Collapse
|
49
|
Sullo P, Cuocolo A, Nicolai E, Cardei S, Nappi A, Squame F, Covelli EM, Pace L, Salvatore M. Quantitative exercise technetium-99m tetrofosmin myocardial tomography for the identification and localization of coronary artery disease. EUROPEAN JOURNAL OF NUCLEAR MEDICINE 1996; 23:648-55. [PMID: 8662093 DOI: 10.1007/bf00834526] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The aim of this study was to evaluate the accuracy of quantitative 1-day exercise-rest technetium-99m tetrofosmin tomography in the identification of patients with coronary artery disease (CAD) and in the detection of individual stenosed coronary vessels. Sixty-one patients with suspected CAD who underwent coronary angiography and 13 normal volunteers were studied. All patients were submitted to two i.v. injections of 99mTc-tetrofosmin, one at peak exercise (370 MBq) and the other (1110 MBq) at rest 3 h after exercise (images 15-30 min after injection for both studies). All patients with CAD (>/=50% luminal stenosis) (n=50) had an abnormal 99mTc-tetrofosmin tomogram. Only one patient without significant coronary narrowing showed abnormal findings. Overall sensitivity, specificity and diagnostic accuracy in the detection of individual stenosed vessels were 77%, 93% and 85%, respectively. Sensitivity and diagnostic accuracy in the identification of individuals stenosed coronary vessels were significantly higher (P<0.05) in patients with single-vessel disease (n=21) than in those with multivessel disease (n=29). Sensitivity, specificity and accuracy for detecting individual diseased vessels were similar in patients without previous myocardial infarction (n=26) and in those with previous myocardial infarction (n=35). In myocardial territories related to non-infarcted areas (n=128), sensitivity and specificity in the detection of stenosed vessels were 70% and 95%, respectively. In infarcted areas (n=55), sensitivity and specificity in the detection of stenosed vessels were 85% (P=NS vs non-infarcted areas) and 75% (P<0.05 vs non-infarcted areas), respectively. Finally, sensitivity was significantly lower (P<0.05) in vascular territories supplied by vessels with moderate stenosis (50%-75%) than in those supplied by vessels with severe stenosis (>75%). The results of this study demonstrate that quantitative 1-day exercise-rest 99mTc-tetrofosmin single-photon emission tomographic imaging is a suitable and accurate technique to identify patients with CAD and to detect individual stenosed coronary vessels.
Collapse
Affiliation(s)
- P Sullo
- Centro per la Medicina Nucleare del Consiglio Nazionale delle Ricerche (CNR) and Cattedra di Medicina Nucleare, Università Federico II, Napoli, Italy
| | | | | | | | | | | | | | | | | |
Collapse
|
50
|
Ahluwalia U, Larcos G, Gruenewald SM, Farlow DC, Fletcher JP. Adenosine thallium-201 scans in patients undergoing elective non-cardiac surgery. THE AUSTRALIAN AND NEW ZEALAND JOURNAL OF SURGERY 1995; 65:780-3. [PMID: 7487725 DOI: 10.1111/j.1445-2197.1995.tb00559.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Dipyridamole Thallium-201 (201Tl) scintigraphy has been used widely for assessment of patients prior to vascular surgery. Recently, Adenosine has been reported to be a safe and useful alternative to Dipyridamole. The purposes of this study were to evaluate the safety and feasibility of the use of Adenosine, to evaluate the correlation of Adenosine 201Tl scans with coronary angiograms (when available) and to evaluate the effect of scan results on clinician management style. Fifty adults with abdominal aortic aneurysm or other vascular disease underwent an intravenous infusion of Adenosine in conjunction with initial and delayed planar 201Tl scans. Images were interpreted qualitatively and quantitatively by the consensus of two or more experienced observers with patients showing transient left ventricular dilatation or redistribution in one or more myocardial segments reported as being at high risk of peri-operative cardiac events. Of the 50 subjects studied, 49 tolerated the maximum infusion dose with 60% experiencing minor transient symptoms. Low (n = 30) and high risk (n = 20) patients were defined according to Adenosine 201Tl scans. Age, gender and clinical characteristics were similar in both groups. Thirteen (65%) high risk subjects had coronary angiography compared with only three (10%) low risk patients. Patients with high-risk 201Tl scans were also more likely to proceed to coronary revascularization prior to non-cardiac surgery [5/20 (25%) vs 1/30 (3%)]. The positive predictive value of high risk 201Tl scans for coronary artery disease was 85%. Thus, Adenosine is considered a useful and safe alternative to Dipyridamole.(ABSTRACT TRUNCATED AT 250 WORDS)
Collapse
Affiliation(s)
- U Ahluwalia
- Department of Nuclear Medicine and Ultrasound, Westmead Hospital, New South Wales, Australia
| | | | | | | | | |
Collapse
|