Noninvasive screening criteria for enhanced 4-year survival after aortocoronary bypass surgery.

Abstract
Two thousand one men with coronary heart disease (CHD) who were enrolled in the Exercise Testing Registry of the Seattle Heart Watch had symptom-limited maximal exercise tests at the initial clinical examination and follow-up surveillance of subsequent mortality for 4.1 +/- 1.6 years. When subdivided into three mutually exclusive subgroups, 636 patients did not have exertional myocardial ischemia, left ventricular dysfunction or cardiomegaly; 885 without cardiomegaly had only exertional ischemia; 480 had left ventricular dysfunction by either cardiomegaly and/or two noninvasive exertional criteria, with or without exertional myocardial ischemia. Three hundred thirty-one men had aortocoronary bypass surgery, while 1670 remained unopened for at least 4 years. Only 34% of the operated patients who had left ventricular dysfunction, as defined, showed a marked improvement in 4-year survival rates (p less than 0.01). Differences in the annual CHD mortality rates in relation to surgical treatment in the other two groups were not statistically significant. Restricting the analysis to a subset of patients who had invasive studies did not alter the conclusion. Accordingly, we suggest the use of noninvasive criteria to aid preliminary screening of patients for invasive studies and surgical treatment.