Impact of patency of the left anterior descending coronary artery on long-term survival

This study examines the relative importance of patency of the left anterior descending (LAD) coronary artery on long-term survival when the LAD is the only significantly narrowed coronary artery. From a cardiac disease registry of 21,786 patients, 826 medically treated patients with isolated LAD disease were identified. These patients were followed for > 5 years. Patients were divided into those with open versus those with closed arteries. With the use of univariate and multivariate analysis, the relative importance of the patency of the LAD was determined. All patients with previous anterior wall infarction were analyzed as a separate group, and those with and without a patent LAD were compared. Overall, survival was significantly better in patients with an open LAD. However, multivariate analysis of either the entire study group or the group with myocardial infarction showed that coronary artery patency was not an independent predictor of long-term survival. Analysis of patients with prior anterior myocardial infarction showed significantly improved 5-year survival in younger patients (< 70 years) who had an open (but stenosed) versus a closed LAD without angiographic collateral formation (94% vs 81%, p = 0.025). Furthermore, this survival difference was most striking in patients with left ventricular dysfunction. Survival in younger patients with an open LAD was similar to that of patients with a closed LAD with collateral formation (94% vs 92%, p = 0.55). No differences in survival were observed in the groups without infarction. This study implies that an open LAD improves long-term survival for younger patients with a previous anterior myocardial infarction and no collateral support to the ischemic or infarcted myocardium.