Coronary Artery Bypass Grafting during Acute Coronary Syndrome: Outcomes and Comparison of Off-Pump to Conventional Coronary Artery Bypass Grafting at a Veteran Affairs Hospital

Abstract

Objective The management of acute coronary syndrome (ACS) has evolved dramatically over the last 50 years. Currently, management includes a multidisciplinary approach potentially including catheter-based therapy, surgery, or purely medical management. Where surgical therapy is indicated, data regarding long-term outcomes are limited. In particular, little data exist regarding on-pump (conventional coronary artery bypass grafting, cCABG) versus off-pump (OPCABG) outcomes for this group. Methods A retrospective review of prospectively collected data was undertaken. Patients undergoing isolated CABG from January 2000 to December 2011 with ACS were identified (n = 271); non-ACS patients (n = 854) were established as a control. Data were analyzed with a χ2 or a t test, where appropriate. Survival was compared using Kaplan-Meier analysis and Cox proportional hazards model. Results Thirty-day mortality between the ACS and the control groups was similar; however, long-term mortality was worse for the ACS group ( P = 0.032; median follow-up, 5.5 years). Length of stay and composite morbidity were higher in the ACS group ( P < 0.01). Subgroup analysis of ACS patients (OPCABG vs cCABG) demonstrated worse preoperative comorbidities in the OPCABG group, but similar 30-day and long-term mortality. However, the cCABG group had higher rates of reoperation ( P = 0.034) and longer length of stay ( P = 0.017) and operative time ( P < 0.0001). Cox proportional hazards model was applied. Risk factors for the non-ACS cohort included age, diabetes, OPCABG, and ACS ( P < 0.05). Among the ACS cohort, only age remained a statistically significant factor ( P < 0.0001). Conclusions ACS appears to negatively impact long-term, but not short-term, mortality. Within the ACS group, OPCABG compares favorably to cCABG in the long-term and also improves short-term morbidity.