This Article Figures Only Full Text Full Text (PDF) View Related Keeping an Eye on Imaging on CVN Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Hiss, F. C. Articles by Simões, M. V. Search for Related Content PubMed Articles by Hiss, F. C. Articles by Simões, M. V. Related Collections Related Article

Changes in Myocardial Perfusion Correlate With Deterioration of Left Ventricular Systolic Function in Chronic Chagas' Cardiomyopathy

Division of Cardiology, University Hospital, Medical School of Ribeirão Preto, University of São Paulo, Brazil

^_* Reprint requests and correspondence: Dr. Marcus V. Simões, Divisão de Cardiologia, Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto, Ribeirão Preto, São Paulo 14048-900, Brazil (Email: msimoes{at}fmrp.usp.br).

Objectives: This study aimed at analyzing the association between myocardial perfusion changes and the progression of left ventricular systolic dysfunction in patients with chronic Chagas' cardiomyopathy (CCC).

Background: Pathological and experimental studies have suggested that coronary microvascular derangement, and consequent myocardial perfusion disturbance, may cause myocardial damage in CCC.

Methods: Patients with CCC (n = 36, ages 57 ± 10 years, 17 males), previously having undergone myocardial perfusion single-positron emission computed tomography and 2-dimensional echocardiography, prospectively underwent a new evaluation after an interval of 5.6 ± 1.5 years. Stress and rest myocardial perfusion defects were quantified using polar maps and normal database comparison.

Results: Between the first and final evaluations, a significant reduction of left ventricular ejection fraction was observed (55 ± 11% and 50 ± 13%, respectively; p = 0.0001), as well as an increase in the area of the perfusion defect at rest (18.8 ± 14.1% and 26.5 ± 19.1%, respectively; p = 0.0075). The individual increase in the perfusion defect area at rest was significantly correlated with the reduction in left ventricular ejection fraction (R = 0.4211, p = 0.0105). Twenty patients with normal coronary arteries (56%) showed reversible perfusion defects involving 10.2 ± 9.7% of the left ventricle. A significant topographic correlation was found between reversible defects and the appearance of new rest perfusion defects at the final evaluation. Of the 47 segments presenting reversible perfusion defects in the initial study, 32 (68%) progressed to perfusion defects at rest, and of the 469 segments not showing reversibility in the initial study, only 41 (8.7%) had the same progression (p < 0.0001, Fisher exact test).

Conclusions: In CCC patients, the progression of left ventricular systolic dysfunction was associated with both the presence of reversible perfusion defects and the increase in perfusion defects at rest. These results support the notion that myocardial perfusion disturbances participate in the pathogenesis of myocardial injury in CCC.

Key Words: myocardial perfusion scintigraphy • chronic Chagas' cardiomyopathy • left ventricular function • microcirculation

Abbreviations and Acronyms   CCC = chronic Chagas' cardiomyopathy   ECG = electrocardiogram   LV = left ventricular   LVEF = left ventricular ejection fraction   SPECT = single-photon emission computed tomography

Related Article

Early Identification and Monitoring Progression of Chagas' Cardiomyopathy With SPECT Myocardial Perfusion Imaging

Ronald G. Schwartz and Orren Wexler
J. Am. Coll. Cardiol. Img. 2009 2: 173-175. [Full Text] [PDF]