THE EFFECT OF PERIPHERAL VASCULAR-DISEASE ON IN-HOSPITAL MORTALITY-RATES WITH CORONARY-ARTERY BYPASS-SURGERY

Purpose: The purpose of this study was to examine the effect of peripheral vascular disease (PVD) on in-hospital mortality rates after coronary artery bypass grafting (CABG). Methods: We performed a regional cohort study of 3003 patients undergoing CABG between 1987 and 1989 at five tertiary care centers in Maine, New Hampshire, and Vermont. Data reflecting patient characteristics, severity of heart disease, comorbidity, and in-hospital mortality rates were collected prospectively; the presence of clinical and subclinical indicators of PVD was determined retrospectively. Results: Observed in-hospital mortality rates with CABG were 2.4-fold higher in the 796 patients with indicators of PVD (7.7%) than in the 2207 patients without PVD (3.2%) (crude odds ratio [OR] 2.42 [95% confidence interval (CI) 1.73-3.37]). After adjusting for their higher comorbidity scores, more advanced heart disease, and age, patients with PVD remained 73% more likely to die in hospital after CABG (adjusted OR 1.73 [CI 1.19-2.51]). The excess risk of in-hospital death associated with PVD was attributable largely to lower extremity occlusive disease (adjusted OR 2.03 [CI 1.34-3.07]). Subclinical lower extremity occlusive disease (asymptomatic absence of pedal pulses) had the same effect as clinically overt disease. Cerebrovascular disease had a small and statistically nonsignificant effect on CABG-related deaths (adjusted OR 1.13 [CI 0.73-1.74]). Excess mortality rates in patients with PVD were primarily due to increased risk of death from heart failure and dysrhythmias, but not to cerebrovascular accidents or peripheral arterial complications. Conclusions: The presence of lower extremity arterial occlusive disease;is an important, independent predictor of in-hospital mortality rates for patients undergoing CABG. Controlled studies of the long-term effects of CABG in patients with PVD are needed to determine the optimal role of myocardial revascularization in this population.