New-onset atrial fibrillation during COVID-19 infection predicts poor prognosis

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has led to a paradigm shift in healthcare worldwide. Little is known about the impact on the cardiovascular system, and the incidence and consequences of new onset of atrial fibrillation (AF) in infected patients remain unclear. The aim of this study was to analyze the cardiovascular outcomes of patients with newonset AF and coronavirus disease 2019 (COVID-19) infection. Methods: This observational study analyzed a sample of 160 consecutive patients hospitalized due to COVID-19. A group with new-onset AF (n = 12) was compared with a control group (total: n = 148, sinus rhythm: n = 118, previous AF: n = 30). New-onset AF patients were significantly older and hypertensive, as well as presenting more frequently with a history of acute coronary syndrome and renal dysfunction. This group showed a higher incidence of thromboembolic events (41.7% vs. 4.1%; p < 0.001), bleeding (33.3% vs. 4.7%, p = 0.005), a combined endpoint of thrombosis and death (58.3% vs. 19.6%, p = 0.006) and longer hospital stays (16.4 vs. 8.6 days, p < 0.001), with no differences in all-cause mortality. Results: In multivariate analysis, adjusted by potential confounding factors, new-onset AF demonstrated a 14.26 odds ratio for thromboembolism (95% confidence interval 2.86-71.10, p < 0.001). Conclusions: New-onset AF in COVID-19 patients presumably has a notable impact on prognosis. The appearance of new-onset AF is related to worse cardiovascular outcomes, considering it as an independent predictor of embolic events. Further studies are needed to identify patients with COVID-19 at high risk of developing "de novo" AF, provide early anticoagulation and minimize the embolic risk of both entities.