Comparative long-term effects of coronary artery bypass graft surgery and percutaneous transluminal coronary angioplasty on regional coronary flow reserve.

Abstract

To evaluate the relative long-term improvement in coronary artery hemodynamics after revascularization by coronary artery bypass graft surgery (CABG) or percutaneous transluminal coronary angioplasty (PTCA), regional coronary flow reserve (CFR) was measured, by digital computer analysis of 35 mm cine film, in 50 men undergoing cardiac catheterization. CFR (mean +/- SEM) in 12 atherosclerotic arteries before revascularization was 1.02 +/- 0.05. Mean CFR in 29 normal arteries of men with normal coronary arteriograms was significantly higher (2.59 +/- 0.11) than that in 16 atherosclerotic arteries of patients revascularized by CABG (2.02 +/- 0.17, p less than .01) or in 14 atherosclerotic arteries of those revascularized by PTCA (1.97 +/- 0.12, p less than .01). No difference in CFR between the CABG and PTCA groups was found and variables known to influence CFR were similar between groups. Equivalent and significant long-term improvement in coronary artery hemodynamics is provided by CABG or PTCA. We postulate that the difference in CFR in the men with normal arteries and those who underwent revascularization was related to the effects of the general atherosclerotic process, which remain despite successful treatment by these techniques.