Comparison of on pump and off pump coronary surgery : risk factors for neurological outcome

Objective: Cerebrovascular accidents (CVA) are devastating complications after coronary artery bypass grafting (CABG). The reported incidence of neurological complications after conventional CABG (CCABG) is 3-6%. Off-pump coronary bypass grafting (OPCAB) has been associated in recent studies to a decreased morbidity and risk of perioperative stroke. Nevertheless, uncertainty still surrounds the relative benefits of OPCAB. We investigated whether, in our experience, OPCAB was associated with lower neurological morbidity than conventional CABG approach. Methods: Eight thousand and two patients underwent isolated CABG at our institution between January 1998 and January 2005. OPCAB operation was performed on 1415 patients. Data were prospectively collected. A multiple logistic regression analysis was used to evaluate the influence of the two different surgical techniques on the neurological outcomes. Results: Patients in the OPCAB group were significantly older (66.2 vs 63.5%, p < 0.0001), had a higher incidence of renal injury (5.4 vs 2.4%, p < 0.0001), and were more redo interventions (6.95 vs 1.53%, p < 0.0001). The CCABG patients were more urgent at operation (5.46 vs 3.26, p = 0.0007), were less hypertensive (57.6 vs 63% of the patients, p = 0.0003) more diabetics (22 vs 20.6%, NS), and had an ejection fraction less than 0.40 (10.4 vs 9.6%, NS). CVA incidence was similar in both groups (Type I outcome: OPCAB = 0.70% vs CCABG = 0.68%, p = 0.91; Type II outcome OPCAB = 0.70% vs CCABG = 0.83%, p = 0.63). Conclusions: In our experience patients undergoing CCABG were not exposed to a grater risk of neurological adverse events when compared to OPCAB patients