HOW SERIOUS IS A PROXIMAL OCCLUSION OF A POSTEROLATERAL SEQUENTIAL BYPASS

The sequential coronary bypass, despite having several demonstrated be nefits, has been criticized for being solely dependent upon 1 proximal anastomosis. The aim of this study was to evaluate the danger of a pr oximal occlusion of a posterolateral sequential bypass graft. Between 1 January 1984 and 31 December 1994, 3,203 patients underwent primary coronary artery bypass grafting with at least 1 sequential vein bypass graft (780 patients received 1 sequential graft and 2,423 patients re ceived 2). There were 5,626 sequential bypass grafts: 3,492 posterolat eral (62%) and 2,134 antero-latero-septal (38%) grafts. There were 73 hospital deaths (2.3%). Follow-up was performed on 3,130 hospital surv ivors (5,504 grafts), for an average of 59 +/- 36 months (range, 1 to 11 years). During follow-up, a total of 250 symptomatic sequential gra ft occlusions occurred in 250 patients (8.0%). Only 23 (0.7%) of the s urviving 3,431 posterolateral sequential bypass grafts had symptomatic proximal occlusion, 35.9 +/- 5.9 months postoperatively, with all the distal anastomoses remaining patent. Twenty-two of the patients so af fected presented with angina and 1 with myocardial infarction. There w as no mortality in 12 patients (52%), medical treatment was sufficient , while 11 patients (48%) underwent successful repeat coronary revascu larization. The operation consisted of a simple vein graft from the ao rta to the distally patent sequential graft in all patients. Four pati ents had additional coronary artery bypass grafting due to progression of the disease. The 10-year survival rate was 86.7%. Symptomatic occl usion of only the proximal segment of posterolateral sequential bypass grafts occurs rarely and has a low risk of myocardial infarction and mortality provided ?hat ?he terminal anastomosis is with a high-flow v essel.