Background
The prognosis of COVID-19 patients with cardiac involvement is unfavorable and it remains unknown which patients are at risk. The virus enters cells via its receptor angiotensin-converting enzyme 2 (ACE2). Myocardial ACE2 expression is increased in structural heart disease (SHD). We, therefore, aimed to analyze correlations between structural heart disease and cardiac SARS-CoV-2 manifestation.
Conclusions
We provide evidence for a correlation between SHD, altered ACE2 receptor expression, and cardiac SARS-CoV-2 manifestation. Consequently, structural heart disease may be considered a distinct risk factor for a severe clinical course after infection with SARS-CoV-2. Registration number local irb: Ethics Committee of Northwestern and Central Switzerland ID 2020-00629; Ethics Committee of the Medical University Innsbruck EK Nr: 1103/2020. Gov number: NCT04416100.
Methods
The clinical course of COVID-19 in patients with structural heart disease was assessed in a prospective cohort of 152 patients. The primary endpoints consisted of hospitalization and survival. Cardiac tissue of 23 autopsy cases with lethal COVID-19 course was obtained and analyzed for (a) the presence of SHD, (b) myocardial presence of SARS-CoV-2 via RT,-PCR, and (c) levels of ACE2 expression using immunofluorescence staining.
Results
Structural heart disease is found in 67 patients, of whom 56 (83.60%) are hospitalized. The myocardium is positive for SARS-CoV-2 in 15 patients (65%) in 23 autopsy cases of lethal COVID-19. Moreover, most hearts with evidence of myocardial SARS-CoV-2 have structural heart disease [11 (91,67%) vs. 1 (8,33%), p = 0.029]. Myocardial presence of SARS-CoV-2 is correlated with a significant downregulation of ACE2 compared to negative control hearts (6.545 ± 1.1818 A.U. vs. 7.764 ± 2.411 A.U., p = 0.003). The clinical course of patients with cardiac SARS-CoV-2 manifestation is unfavorable, resulting in impaired survival (median, 12 days and 4.5 days, respectively, HR 0.30, 95% CI, 0.13 to 0.73, p = 0.0005) CONCLUSIONS: We provide evidence for a correlation between SHD, altered ACE2 receptor expression, and cardiac SARS-CoV-2 manifestation. Consequently, structural heart disease may be considered a distinct risk factor for a severe clinical course after infection with SARS-CoV-2. Registration number local irb: Ethics Committee of Northwestern and Central Switzerland ID 2020-00629; Ethics Committee of the Medical University Innsbruck EK Nr: 1103/2020. Gov number: NCT04416100.