Risk stratification in stable angina pectoris

Abstract

M anagement of patients with hemodynamically significant atherosclerotic coronary artery disease (CAD) and disabling angina pectoris who are receiving a maximal medical regimen is straightforward. Provided the coronary anatomy is suitable, a revascularization procedure, either percutaneous transluminal coronary angioplasty or coronary artery bypass graft surgery (CABG), is usually indicated; this provides relief of symptoms in most patients.’ It is generally accepted that CABG improves the survival rate among patients with stenosis of the left main coronary arteryzJ and in selected patients with 3vessel CAD.3-5 The Coronary Artery Surgery Study (CASS] reported survival data on a subset of patients with mild stable angina pectoris and moderate impairment of left ventricular (LV) function.4 One hundred sixty patients with LV ejection fractions of 35 to 49% were randomly assigned to either surgical or medical therapy. Seven-year cumulative survival rates favored surgical over medical therapy (84% vs 70% survival]. This statistically significant difference in survival was almost entirely due to the reduced mortality rates of surgical patients with 3-vessel CAD; there were no differences in survival in patients with lor 2-vessel CAD. Similar survival data favoring surgical therapy in patients with 3-vessel CAD and impaired LV function (global ejection fraction less than 50% or wall motion abnormality involving more than 25% of the heart border) were reported in the Veterans Administration (VA) study [at 7 years 76% vs 5270, at 11 years 50% vs 3870).~ Recent nonrandomized studies evaluating patients with angina, multivessel CAD and severe LV dysfunction [ejection fraction less than 35%) also reveal improved survival with CABG.6*7 Mildly symptomatic patients with lor X-vessel CAD (not involving the proximal left anterior descending coronary artery) do not appear to derive benefit from elective CABG2v3J; medical and surgical survival rates were similar in patients with normal and in those with impaired LV function. However, management of patients with nondisabling angina pectoris, 2or 3-vessel CAD (including