[Myocardial perfusion assessed by dynamic computed tomography before and after percutaneous transluminal coronary...

A method for quantitatively and visually assessing myocardial perfusion using a new transmission computed tomography scanner and contrast media injection was devised. Myocardial perfusion was assessed before and after percutaneous transluminal coronary angioplasty (PTCA). Six patients with left anterior descending coronary artery stenosis undergoing PTCA were successfully studied. Dynamic scans, each with a scan time of one sec, were performed at the mid left ventricular level using bolus injections of contrast medium from the inferior vena cava. Regions of interest (ROIs) were located in the left ventricular cavity and in the myocardium perfused by the left anterior descending coronary artery, and gamma-variate fitted time density curves were recorded within the first pass phase, excluding recirculation. Cardiac outputs calculated from the ventricular curves of the ROIs in the left ventricular cavity correlated well with the thermodilution measurements using Swan-Ganz catheters (r = 0.90, p less than 0.01). The ratios of myocardial blood flow (F) to the tissue element volume (V) were calculated (F/V) from the myocardial curves of the ROIs in the myocardium as parameters of myocardial perfusion, according to the Zierler's principle. The F/Vs in the myocardium perfused by the left anterior descending coronary artery before PTCA were significantly less than those of the control subjects (4.4 x 10(-2) +/- 1.2 x 10(-2) vs 8.1 x 10(-2) +/- 2.9 x 10(-2): p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)