Concepts for Coronary Flow and Myocardial Perfusion Measurements

Abstract

As a technique, coronary angiography provides an opportunity to evaluate not only morphologic but also functional information of the coronary circulation. Until recently, visual interpretation of the temporal course of vascular contrast flow was the only method to detect regional flow abnormalities. For example, delayed contrast opacification was considered a reflection of reduced blood flow. Obvious limitations in the visual assessment of abnormal vascular perfusion result from diagnostic uncertainties inherent in subjective evaluation. Consequently, several methods have been suggested that measure transit-times of the contrast bolus along vascular segments by roentgen densitometry [1, 2]. These studies were helpful both in testing specific applications and in understanding particular problems encountered in quantitative contrast dilution methods. However, limited practicality of this roentgen densitometric technique impeded its general acceptance for routine clinical use.