PREDICTORS OF DISEASE SEVERITY AND SURVIVAL IN PATIENTS WITH CORONARY-ARTERY DISEASE

Background: The objective of this study was to determine whether coronary angiographic findings and survival could be predicted using standard clinical and exercise-test data. Methods: Five hundred and ninety-five men who had undergone both exercise treadmill testing and cardiac catheterization were followed for up to 5 years. Left main (LM) disease (greater-than-or equal-to 50% stenosis) was present in 42 patients, whereas 30 patients had LM equivalent disease (greater-than-or-equal-to 70% stenosis of both the proximal left anterior descending and circumflex coronary arteries). Patients were divided into six exclusive groups using angiography: no coronary artery disease (n = 152), one-vessel disease (n = 186), two-vessel disease (n = 11 8), three-vessel disease (n = 67), LM or LM equivalent disease without significant (greater-than-or-equal-to 70%) right coronary artery involvement (n = 26), and LM or LM equivalent disease with right coronary artery involvement (n = 46). Results: ST-segment depression was more marked, whereas ejection fraction, maximal heart rate, maximal systolic blood pressure, and exercise capacity were lower in each group as disease severity worsened. Using Kaplan-Meier analysis, the subgroup with the poorest survival was found to be those with LM or LM equivalent disease with right coronary artery disease, and the next worse was the three-vessel disease group, in which survival was poorer than in all other subgroups (P<0.01). Stepwise regression analysis revealed that the most powerful predictor for coronary artery disease severity was exercise-induced ST depression (P<0.001), but it predicted survival poorly. History of congestive heart failure, low ejection fraction (50% or lower), and poor exercise capacity (5 metabolic equivalents or less) emerged as strong predictors of survival using stepwise Cox regression analysis (P<0.001). Conclusion: Exercise-induced ST depression predicted the severity of angiographic disease but not survival, whereas the strongest predictors of survival were history of congestive heart failure, low ejection fraction, and poor exercise capacity.