Cardiac surgery on patients with <scp>COVID</scp> ‐19: a systematic review and <scp>meta‐analysis</scp>

The COVID-19 pandemic has had a significant impact on global surgery. In particular, deleterious effects of SARS-CoV-2 infection on the heart and cardiovascular system have been described. To inform surgical patients, we performed a systematic review and meta-analysis aiming to characterize outcomes of COVID-19 positive patients undergoing cardiac surgery.The study protocol was registered with PROSPERO (CRD42021228533) and conformed with PRISMA 2020 and MOOSE guidelines. PubMed, Ovid MEDLINE and Web of Science were searched between 1 January 2019 to 24 February 2022 for studies reporting outcomes on COVID-19 positive patients undergoing cardiac surgery. Study screening, data extraction and risk of bias assessment were conducted in duplicate. Meta-analysis was conducted using a random-effects model where at least two studies had sufficient data for that variable.Searches identified 4223 articles of which 18 studies were included with a total 44 patients undergoing cardiac surgery. Within these studies, 12 (66.7%) reported populations undergoing coronary artery bypass graft (CABG) surgery, three (16.7%) aortic valve replacements (AVR) and three (16.7%) aortic dissection repairs. Overall mean postoperative length of ICU stay was 3.39 (95% confidence interval (CI): 0.38, 6.39) and mean postoperative length of hospital stay was 17.88 (95% CI: 14.57, 21.19).This systematic review and meta-analysis investigated studies of limited quality which characterized cardiac surgery in COVID-19 positive patients and demonstrates that these patients have poor outcomes. Further issues to be explored are effects of COVID-19 on decision-making in cardiac surgery, and effects of COVID-19 on the cardiovascular system at a cellular level.