Contemporary percutaneous treatment of unprotected left main coronary stenoses: Initial results from a multicenter registry analysis 1994-1996

Background: Coronary artery bypass surgery (CABG) has been considered the therapy of choice for patients with unprotected left main (ULMT) coronary stenoses. Selected single-center reports suggest that the results of percutaneous intervention may now approach those of CABG. Methods and Results: To assess the results of percutaneous ULMT treatment from a wide variety of experienced interventional centers, we requested data on consecutive patients treated after January 1, 1994, from 25 centers. One hundred seven patients were identified who were treated either electively (n=91) or for acute myocardial infarction (n=16). Of patients treated electively, 25% were considered inoperable, and 27% were considered high risk for bypass surgery. Primary treatment included stents (50%), directional atherectomy (24%), and balloon angioplasty (20%). Follow-up was 98.8% complete at 15±8 months. Results varied considerably, depending on presentation and treatment for patients with acute myocardial infarction, technical success was achieved in 75%, and survival to hospital discharge was 31%. For elective patients, technical success was achieved in 98.9%, and in- hospital survival was strongly correlated with left ventricular ejection fraction (P=.003). Longer-term event (death, infarction, or bypass surgery) - free survival was correlated with ejection fraction (P<.001) and was inversely related to presentation with progressive or rest angina (P<.001). Surgical candidates with ejection fractions ≤40% had an in-hospital survival of 98% and a 9-month event-free survival of 86±5%, whereas patients with ejection fractions <40% had 67% and 22±12% in-hospital and 9-month event- free survivals, respectively. Nine hospital survivors (10.6%) experienced cardiac death within 6 months of hospital discharge. Conclusions: While results for selected patients appear promising, until early post-hospital discharge cardiac death can be better understood and minimized percutaneous revascularization of ULMT stenosis should not be considered an alternative to bypass surgery for most patients. When percutaneous revascularization of ULMT is required, directional atherectomy and stenting appear to be the preferred techniques, and follow-up angiography 6 to 8 weeks after treatment is probably advisable.