Estudo comparativo da identificacao de isquemia miocardica pela cineventriculografia contrastada sob o efeito de mononitrato de isossorbitol e pela cintilografia miocardica perfusional em portadores de cardiopatia isquemica

Abstract

Objective – To evaluate and compare the usefulness of cineventriculographies, before and after nitrate use, to technetium-99m sestamibi scintigraphy for the identification of myocardial ischemia. Methods – Twenty-six patients were studied at basal conditions and 5 minutes after intravenous administration of isosorbide mononitrate (0.3mg/kg), to evaluate the performance and regional wall motion of the left ventricle (LV). The results were compared to those obtained with technetium- 99m sestamibi scintigraphy. Results – Before nitrate, contrast ventriculography identified 30 normal segments, 62 hypokinetic segments, 28 dyskinetic segments, and 14 akinetic segments. After drug administration, 99 segments were normal, 11 hypokinetic, 11 dyskinetic, and 13 akinetic. Myocardial scintigraphy revealed 110 ischemic segments and 18 fibrotic segments (p<0.005). After drug administration, the ventriculography showed increase in the velocity of circumferential fiber shortening (p=0.0142), the ejection fraction (p=0.0462), decrease in the end-systolic volume (p=0.0031) and no change in end-diastolic volume. Conclusion – Contrast ventriculography using nitrate proved to be similar to perfusional myocardial scintigraphy in the identification of myocardial ischemia.