Difficulties in the interpretation of coronary angiogram early after coronary artery bypass surgery on the beating heart

Abstract

OBJECTIVE: The major objective of this study was to evaluate the findings in early postoperative coronary angiography in patients who underwent coronary revascularization on the beating heart without cardiopulmonary bypass. METHODS: Eighty-four consecutive patients receiving 113 grafts were studied. A coronary angiography was performed 0 to 5 days postoperatively. All the grafts were reviewed and classified in the following way: grade A (unimpaired run-off); grade B1 (<50 stenosis); grade B2 (>50% stenosis); grade O (occlusion). A second coronary angiography was performed in patients with a stenosis grade B2, 4 to 30 months postoperatively. An exercise test was performed by patients with B1 stenosis. RESULTS: Overall graft patency was 96% in the 113 grafts. None of the 14 patients with B1 stenosis in the early coronary angiography had any clinical signs of ischemia. Eight of the 12 patients who exhibited B2 stenosis either at the anastomotic site, in the graft or in the distal coronary artery at the first coronary angiography had a normal angiogram at the re-angiography. CONCLUSION: A majority of stenoses visualized at the early coronary angiography could not be seen at a later coronary angiography, which makes the interpretation of the angiogram unreliable as a tool for the decision as to redo-procedure in the early postoperative period.