Management of asymptomatic mild aortic stenosis during coronary artery operations

Background. Management of asymptomatic mild aortic stenosis at the time of coronary artery bypass grafting (CABG) remains controversial. We have retrospectively analyzed a cohort of patients requiring aortic valve replacement (AVR) subsequent to CABG and compared their operative morbidity and mortality with that of a group receiving CABG and AVR simultaneously at the first operation. Methods. Analysis is drawn from 28 patients who required AVR 8 +/- 4 years subsequent to CABG (group A) and 175 patients receiving AVR along with CABG at the primary operation (group B). Groups were similar with respect to age, sex, risk factors for cardiac disease, extent of coronary artery disease, left ventricular function, New York Heart Association class, aortic valve area, number of grafts, and size of prosthesis inserted. Results. Patients having AVR subsequent to CABG had a significantly prolonged aortic cross-clamp time and global myocardial ischemic time and incurred a twofold increase in operative mortality. The actuarial survival at 10 years was not significantly different between cohorts. In the 28 patients in group A, the aortic valve area during the period between operations decreased 0.05 mm(2)/y. Conclusions. The operative mortality and morbidity of a second operation for AVR is high, but there is no significant difference in survival at 10 years. In at least a portion of patients having mild aortic stenosis at the time of CABG there will be progression of the stenosis necessitating reoperation at a later date.