Relationship Between Cardiac Surgery and Acute Ischemic Stroke: An Examination in Terms of Clinical, Radiological, and Functional Outcomes and Possible Pathophysiological Mechanisms.

Aim: The aim is to discuss the clinical characteristics, time, anatomical vascular distribution, radiological features, functional outcomes after stroke and possible pathophysiological mechanisms of acute ischemic stroke (AIS) that develop after cardiac surgery.

Method: A total of 3,474 patients, who underwent cardiac surgery between 2015-2020, retrospectively were analyzed. Forty-nine patients, who developed AIS and had brain CT and diffusion MR images during hospitalization, were included in the study.

Results: AIS distribution was at 53% CABG, 12.2% isolated mitral valve, 8.1% isolated aortic valve, and 26.5% combined surgical procedures. Patients with a ≤2 days (P = 0.03) preop preparation time and body surface area (BSA) of <1.85 m2 (P = 0.02) had a high discharge rate. While newly developing AF was low in the early stroke group, it was higher in the late stroke group (P = 0.02). A history of previous cerebrovascular events was found in 3.3% of the patients. Postoperative new AIS was detected in 7.8% of those with a history of cerebrovascular events. Total anterior circulation infarction (TACI) case rate was 8.1%, partial anterior circulation infarction (PACI) 12.2%, posterior circulation infarction (POCI) 24.4%, cortical border zone infarction (CBZI) 30.6%, combined POCI + CBZI 12.2%, multiple territorial infarcts (MTI) 10.2%, and lacunar circulation infarction (LACI) rate was 2%. The modified Rankin Scale means following AIS was 3.45. The worst Rankin score was 5.75 in CABG+MVR cases; it was found to be 5 in the valve + ascending aorta case and 5 in the five bypass cases.

Conclusion: Calculation of cerebrovascular reserve with extra/intracranial vascular imaging is important in patients with multiple risk factors, whose association with stroke has been determined before cardiac surgery. We believe that cardiovascular surgery and neurology multidisciplinary prospective randomized studies should be conducted to obtain pre-, peri- and post-procedural risk calculation scales, according to cardiac surgery type and to reshape surgical procedures accordingly.