Myocardium selective densitometric perfusion assessment after acute myocardial infarction

Abstract

Myocardial perfusion is an important prognostic factor after recanalisation in acute myocardial infarction patients. We present a computerized, densitometric measurement method to assess myocardial perfusion on phase-matched digitally subtracted coronary angiograms. Quantitative myocardial perfusion was assessed by the G(max)/T(max) parameter of the time-density curves (TDCs) in infarct-related myocardial regions on X-ray coronary angiograms. Arteries were masked out from regions of measurement. This novel method has been compared with enzymatic infarct size, ST-segment resolution, and ejection fraction after successful revascularization of 62 patients with acute myocardial infarction. Significant correlations were found between G(max)/T(max) and enzymatic infarct size (R=-0.445, P<.001), ST-segment resolution (R=0.364, P=.004), and ejection fraction (R=0.278, P=.029). Bland and Altman plot of G(max)/T(max) reveals good interobserver agreement. G(max)/T(max) of the TDC measured in the infarct-related myocardial area is a reliable parameter to assess clinical indicators of myocardial reperfusion. Therefore, results suggest that it could be used to immediately assess the success of recanalisation at the tissue perfusion level during coronary intervention, and as an objective end point in clinical trials of new interventional devices and drugs.