LEFT MAIN STENOSIS AFTER BYPASS-GRAFTING - INDICATION FOR ELECTIVE PTCA

The unprotected left main stenosis still represents one of the contrai ndications of PTCA; recently developed concepts using percutaneous byp ass techniques have not changed this fact so far. However, following b ypass grafting the procedure can be done with low risk and may improve prognosis in case of later bypass occlusion. This study should clarif y whether a higher rate of bypass occlusion is caused by postsurgical left main PTCA. From October 1981 to January 1991 a left main stenosis was dilated in 41 patients, 2 weeks to 12 years (mean 3.5 years) afte r bypass grafting. To date, 17/65 venous bypass grafts were already oc cluded, and 72.4% of the patients suffered from typical angina. In 34/ 41 patients (82.9%) PTCA was successful, severe complications (death, emergency surgery or myocardial infarction) did not occur and clinical improvement was achieved in 80% of symptomatic patients. Four months later, 26/34 patients (76.5%) had angiographic follow-up. Fifteen rest enoses were found and a second PTCA was performed in 9/15. None of the venous bypass grafts, open at the time of the first PTCA, was occlude d at follow-up. In one case PTCA of the left main stenosis turned out to be life-saving 7 years later because an occlusion of RCA- and LCX-b ypasses occurred and the LAD graft showed a subtotal thrombosis. It is concluded that PTCA of left main stenosis after bypass grafting is a safe procedure and does not lead to a higher rate of venous bypass occ lusions. A prognostic indication seems to be justified.