Early neuropsychological dysfunction in elderly high-risk patients after on-pump and off-pump coronary bypass surgery

Abstract

Advanced age is associated with systemic atherosclerosis and is a risk factor for neurological dysfunction after coronary artery bypass grafting (CABG). However, few studies have investigated early neurological dysfunction after off-pump CABG in elderly patients. Data were collected prospectively on 218 patients (≥60 years) who underwent elective off-pump (n = 89) or on-pump CABG (n = 129). Four cognitive tests were performed preoperatively and 1 week postoperatively. Neuropsychological (NP) dysfunction was defined as a decrease in an individual's performance in more than two tests of at least 20% from baseline. We compared the incidence of NP dysfunction, stroke, graft patency grading, and systemic atherosclerosis between patients who underwent off-pump and on-pump CABG. Off-pump patients were more likely to have a history of cerebrovascular disease, peripheral vascular disease, smoking, multiple cerebral infarctions, and severe aortic atherosclerosis. None of the off-pump and three on-pump patients suffered intraoperative strokes (P = 0.27). The incidence of NP dysfunction was 11.2% in the off-pump group and 22.5% in the on-pump group, (P = 0.02). Multivariate analysis revealed that NP dysfunction was associated with cardiopulmonary bypass (CPB) and multiple cerebral infarctions. The off-pump group had fewer vessels grafted (2.4 vs 3.4; P < 0.01), and a higher rate of stenosis (>50%) and occlusion of the grafted vessels (13.0% vs 7.4%; P = 0.01) than the on-pump group. Off-pump CABG reduced postoperative NP dysfunction in elderly patients with severe systemic atherosclerosis compared to on-pump CABG.