Neurobehavioural sequelae of cardiopulmonary bypass

The development of coronary artery bypass grafting (CABG) and its effect on angina is the product of a series of technical and scientific advances. De spite these advances, however, adverse neurobehavioural outcomes continue t o occur. Stroke is the most serious complication of CARS, but studies that have identified demographic and medical risk factors available before surge ry are an important advance. Short-term cognitive deficits are common after CABG, but may not be specific to this procedure. However, deficits in some cognitive areas such as visuoconstruction persist over time, and may refle ct parieto-occipital watershed area injury secondary to hypoperfusion or em bolic factors. Risk factors for cognitive decline may be time dependent, wi th short-term studies identifying factors that differ from those of long-te rm studies. Patients with depression before surgery are likely to have pers istent depression afterwards. However, depression does not account for the cognitive decline after CARS. Since CARS is increasingly done in older pati ents with more comorbidity, the challenge is to identify patients at risk o f adverse neurocognitive outcomes and to protect them by modification of th e surgical procedure or by effective medical therapy.