MANAGEMENT OF MILD AORTIC-STENOSIS DURING CORONARY-ARTERY BYPASS GRAFT-SURGERY

A small proportion of patients with significant coronary artery diseas e referred for coronary artery bypass graft (CABG) surgery have coexis tent congenital or valvular disease that, if isolated, would be inadeq uately severe to justify surgery. While there is general agreement tha t CABG should be performed for obstruction of major epicardial arterie s even without ischemic symptoms in patients having aortic valve repla cement (AVR) for aortic stenosis (AS), there has been little or no con sideration of whether ''mild-to-moderate'' AS should be treated by val ve repair or AVR at the time of CABG. Between 1975 and 1992, we perfor med AVR for symptoms or signs of severe AS without significant ischemi a on 44 patients with previous CABG. None of these patients were consi dered to have serious AS at the time of CABG surgery to 164 months 68B AR months) previously. At aortic surgery, ages ranged from 52 to 83 ye ars (73BAR); 38% were female. In 20 patients with available data, tran svalvular gradients ranged from 0 to 23 (12BAR) mmHg at CABG and 29 to 95 (62BAR) mmHg at AVR. Aortic valve areas at CABG ranged from 0.9 to 2.2 (1.5BAR) cm2 and at AVR ranged from 0.3 to 1.7 (0.7BAR) CM2. Appe arance of symptoms and signs of severe AS occurred in 16% by 3 years; 45% by 4 years; and 75% by 5 years after CABG surgery. These data obse rvations suggest that mild, asymptomatic valve deformity may progress to symptomatic, hemodynamically severe AS within a short time after CA BG surgery, well before recurrent symptoms of coronary obstructive dis ease. Serious consideration of AVR should be entertained for patients with any degree of aortic valve obstruction who must undergo CABG surg ery.