Abstract P2194: Investigating The Role Of Angiotensin II In The Pathogenesis Of Atrial Fibrillation In Covid-19 Patients Through Blocking The Renin-Angiotensin-Aldosterone System

Abstract

Background: COVID-19 was found to be associated with a greater risk of developing atrial fibrillation (AF). It is thought that COVID-19 enters cells using its surface spike protein, which binds to the ACE-2 receptor and downregulates it. One of the functions of ACE-2 is converting the pro-inflammatory, anti-fibrinolytic angiotensin II (Ang II) to angiotensin I (Ang I). Therefore, when ACE-2 is downregulated, more Ang II is available to trigger its downstream detrimental effects. Thus, we hypothesized that blocking the effects of Ang II using ACE inhibitors (ACEis) or ARBs would confer a protective effect against the risk of AF. Objective: The purpose of this project was to conduct a retrospective cohort study to determine whether treatment with an ACEi/ARB would prevent the development of AF in patients hospitalized for COVID-19. This would help us better understand the pathogenesis of AF in COVID-19 patients. It would also help us decide whether prophylactic treatment with ACEi/ARB would help reduce the risk. Methods: We reviewed the records of all patients admitted for at least seven days for COVID-19 between January 2021 and June 2021. Of 5430 charts, 188 met the inclusion criteria. Results: Approximately 4.8% of patients hospitalized for COVID-19 developed AF. About 6.74% of patients that were not on an ACEi/ARB at any point during their hospitalization developed AF, whereas none of the patients on an ACEi/ARB developed AF, making the relative risk (RR) 0.1871 (95% CI 0.0108 to 3.2377, p-value 0.2492), and the number needed to treat 14.8. Interestingly, in the patients with a previous diagnosis of AF, there was also no statistically significant difference in the need to escalate rate or rhythm control strategy between patients on an ACEi/ARB compared to those who were not (6.67% vs 14.29%, respectively), with a RR of 0.4667 (95% CI: 0.0546 - 4.0629, p-value 0.4900). Conclusion: Our data to date show that the use of an ACEi/ARB is not associated with a statistically significant decrease in the risk of AF in patients hospitalized with COVID-19, which suggests that there may be another cellular mechanism by which COVID-19 causes AF. Therefore, prophylactically treating patients with an ACEi/ARB or holding them on admission may have no influence on the risk of AF.