Long-term RAAS Dysregulation in Post-COVID-19 Cardiovascular Complications: AT-II and ACE2 Imbalance

Introduction: Severe acute respiratory syndrome coronavirus 2, the causative agent of coronavirus disease 2019 (COVID-19), is associated with various cardiovascular complications. Aim: This observational study investigated long-term changes in angiotensin system components, specifically angiotensin II (AT-II) and angiotensin-converting enzyme 2 (ACE2), in patients with and without cardiovascular complications following COVID-19 infection. Methods: The study included 122 adults aged 22-72 years, divided into a control group (mild COVID-19 without pneumonia or heart issues), group I (COVID-19 with lung involvement but no heart complications), and group II (COVID-19 with lung damage and heart complications). Blood samples were obtained one year after acute COVID-19, and serum concentrations of AT-II and ACE2 activity were measured using enzyme-linked immunosorbent assay kits. Results: The results showed a significant increase in AT-II levels and a decrease in ACE2 activity in Group II compared to the control and Group I. In group II, 73% of patients had elevated AT-II levels and 77% showed reduced ACE2 activity, indicating a persistent imbalance between the regulatory and counterregulatory components of the angiotensin system. Conclusion: This study showed that increased AT-II levels and decreased ACE2 activity may contribute to cardiovascular problems during post-acute COVID-19 infection.