There is overlap in myocardial viability detection by thallium-201 uptake and contractile reserve (CR) using low-dose dobutamine (LDD). The dual isotope protocol was modified in this study by acquiring thallium-201 images using LDD to enhance viability detection in addition to coronary flow reserve assessment. One hundred twenty-four patients with coronary disease underwent gated single-photon emission computed tomographic thallium-201 imaging at rest with LDD (10 microg/kg/min) during acquisition followed by stress technetium-99m sestamibi myocardial perfusion (MP) imaging with dobutamine, adenosine, or treadmill exercise. F-18-fluorodeoxyglucose (FDG) positron emission tomography was obtained in 41 patients. Myocardial perfusion (MP) imaging was divided into normal, fixed, and ischemic segments, and subclassified by wall motion and/or thickening changes between 1-hour poststress and LDD into normal, fixed, or improved dysfunctional segments (CR present). Mean left ventricular ejection fraction was 39% at 1 hour after stress and 47% with LDD (p <0.001). In dysfunctional myocardium, CR was significantly higher (p <0.001) in ischemic (233 of 368) and fixed segments (150 of 335) than in normal MP segments (43 of 220). Combined MP and CR analysis showed higher accuracy and negative predictive value in identifying FDG-viable myocardium than either method alone, whereas a high positive predictive value was maintained, similar to both markers. Quantitative analysis showed significant increased wall motion and thickening with LDD compared with 1 hour after stress, which was highest in ischemic segments and lowest in fixed segments. Thus, LDD dual isotope is a practical protocol that improves viability detection by simultaneous MP and CR analysis in addition to coronary flow reserve assessment in 1 study. Moreover, it requires no extra imaging time or radioactivity than the routine protocol.
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http://dx.doi.org/10.1016/j.amjcard.2003.10.008 | DOI Listing |
Cochrane Database Syst Rev
November 2024
Department of Congenital Heart Disease and Pediatric Cardiology, University Heart Center, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.
Background: Paediatric patients undergoing surgery for congenital heart disease (CHD) are at risk for postoperative low cardiac output syndrome (LCOS) and mortality. LCOS affects up to 25% of children after heart surgery. It consists of reduced myocardial function and increases postoperative morbidity, prolongs mechanical ventilation, and lengthens the duration of intensive care unit (ICU) stay.
View Article and Find Full Text PDFTrials
October 2024
Department of Cardiology, The Heart Centre, Copenhagen University Hospital - Rigshospitalet, Blegdamsvej 2142, Copenhagen, DK-2100, Denmark.
Clin Gastroenterol Hepatol
August 2024
Department of Medicine, University of Melbourne, Victoria, Australia; Victorian Liver Transplant Unit, Austin Health, Heidelberg, Australia; Australian Centre for Transplantation Excellence and Research, Melbourne, Australia; Australian Cardiovascular Collaborative in Liver Transplant Medicine, Melbourne, Australia. Electronic address:
JA Clin Rep
August 2024
Department of Anesthesiology, Kumamoto University Hospital, 1-1-1, Honjo, Chuo-Ku, Kumamoto, 860-8556, Japan.
Background: Mitochondrial cardiomyopathy occurs when impaired mitochondrial energy production leads to myocardial dysfunction. Anesthetic management in such cases is challenging due to risks of circulatory depression associated with anesthesia and mitochondrial dysfunction induced by anesthetics. Although there are reports of anesthetic management for patients with mitochondrial diseases, there are few reports specifically addressing cardiac anesthesia for patients with mitochondrial cardiomyopathy.
View Article and Find Full Text PDFEur Heart J Imaging Methods Pract
January 2024
Department of Echocardiography, Harefield Hospital, Royal Brompton and Harefield Hospitals (part of Guy's and St Thomas' NHS Foundation Trust), Hill End Rd, Harefield, Uxbridge UB9 6JH, UK.
Aims: Myocardial response to stress echocardiography may be elicited physiologically, through exercise, or pharmacologically, often with dobutamine. Both have advantages but also limitations due to reduced exercise capacity or side-effects to stressor agent/lack of closeness to true pathophysiology of ischaemic cascade. We have combined low-dose dobutamine and exercise, creating a 'hybrid' protocol to utilize the advantages of both techniques and limit the drawbacks.
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