RESULTS OF A REGIONAL STUDY OF MODES OF DEATH ASSOCIATED WITH CORONARY-ARTERY BYPASS-GRAFTING

Background. It is well known that surgeon-specific in-hospital mortali ty rates for coronary artery bypass grafting vary, but this aggregate measure does not suggest specific opportunities for improvement. Metho ds. We performed a regional prospective study of 8,641 consecutive pat ients undergoing isolated coronary artery bypass grafting by all of th e 23 cardiothoracic surgeons practicing in northern New England during the study period. Mode of death was assigned by an end points committ ee using predetermined definitions. Surgeons were ranked according td risk-adjusted mortality rates and grouped in terciles, and cause-speci fic mortality rates were determined. Results. The mortality rate was 3 .3% in the lowest surgeon mortality tercile and 5.8% in the highest te rcile. Fatal heart failure accounted for 80.0% of the difference in ag gregate mortality rates, ranging from 1.9% in lowest surgeon mortality tercile to 4.0% in the highest tercile (p < 0.001). Rates of other ca uses did not differ significantly across surgeon mortality terciles. D ifferences in rates of fatal heart failure could not be explained by d ifferences in preoperative left ventricular dysfunction or other patie nt characteristics. Conclusions. Most of the difference in observed mo rtality rates across surgeons is attributable to differences in rates of heart failure. (Ann Thorac Surg 1998;66:1323-8) (C) 1998 by The Soc iety of Thoracic Surgeons