Table of Contents
Cardiovascular Psychiatry and Neurology
Volume 2015, Article ID 370612, 12 pages
Review Article

Risk Factors Associated with Cognitive Decline after Cardiac Surgery: A Systematic Review

1Department of Cardiovascular Sciences, University of Leicester, Leicester LE2 7LX, UK
2Leicester Cardiovascular Biomedical Research Unit, Glenfield Hospital, Leicester LE3 9QP, UK
3University Hospitals of Leicester NHS Trust, Leicester LE1 5WW, UK
4Department of Medical Physics, University Hospitals of Leicester NHS Trust, Leicester LE1 5WW, UK

Received 10 August 2015; Accepted 15 September 2015

Academic Editor: Koichi Hirata

Copyright © 2015 Nikil Patel et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Modern day cardiac surgery evolved upon the advent of cardiopulmonary bypass machines (CPB) in the 1950s. Following this development, cardiac surgery in recent years has improved significantly. Despite such advances and the introduction of new technologies, neurological sequelae after cardiac surgery still exist. Ischaemic stroke, delirium, and cognitive impairment cause significant morbidity and mortality and unfortunately remain common complications. Postoperative cognitive decline (POCD) is believed to be associated with the presence of new ischaemic lesions originating from emboli entering the cerebral circulation during surgery. Cardiopulmonary bypass was thought to be the reason of POCD, but randomised controlled trials comparing with off-pump surgery show contradictory results. Attention has now turned to the growing evidence that perioperative risk factors, as well as patient-related risk factors, play an important role in early and late POCD. Clearly, identifying the mechanism of POCD is challenging. The purpose of this systematic review is to discuss the literature that has investigated patient and perioperative risk factors to better understand the magnitude of the risk factors associated with POCD after cardiac surgery.