Prediction of coronary artery disease in patients undergoing operations for mitral valve degeneration

Objectives: We sought to develop and validate a model that estimates the ri sk of obstructive coronary artery disease in patients undergoing operations for mitral valva degeneration and to demonstrate its potential clinical ut ility. Methods: A total of 722 patients (67% men; age, 61 +/- 12 years) without a history of myocardial infarction, ischemic electrocardiographic changes, or angina who underwent routine coronary angiography before mitral valve prol apse operations between 1989 and 1996 were analyzed, A bootstrap-validated logistic regression model on the basis of clinical risk factors was develop ed to identify low-risk (less than or equal to5%) patients. Obstructive cor onary atherosclerosis was defined as 50% or more luminal narrowing in one o r mol p major epicardial vessels, as determined by means of coronary angiog raphy. Results: One hunched thirty-nine (19%) patients had obstructive coronary at herosclerosis. independent predictors of coronary artery disease include ag e, male sex, hypertension. diabetes mellitus,and hyperlipidemia. Two hundre d twenty patients were designated as low I isl; according to the logistic m odel. Of these patients, only 3 (1.3%) had single-vessel disease, and none had multivessel disease. The model showed good discrimination, with an area under the receiver-operating characteristic curve of 0.84, Cost analysis i ndicated that application of this model could safely eliminate 30% of coron ary angiograms, corresponding to cost savings of $430,000 per 1000 patients without missing any case of high-risk coronary artery disease. Conclusion: A model with standard clinical predictors can reliably estimate the prevalence of obstructive coronary atherosclerosis in patients undergo ing mit;al valve prolapse operations. This model call identify low-risk pat ients in whom routine preoperative angiography may be safely avoided.