Rate of acute myocarditis low in hospitalized patients with COVID-19
The prevalence of acute myocarditis was low in hospitalized patients with COVID-19 during the first 14 months of the pandemic, researchers reported in Circulation.
The researchers conducted a retrospective cohort study of 56,963 hospitalized patients with COVID-19 from 23 centers in the United States and Europe from February 2020 to April 2021.
“While COVID-19 is a virus that predominantly leads to acute respiratory illness, there has been a small group of individuals who also experience cardiac complications,” Enrico Ammirati, MD, PhD, a cardiologist at De Gasperis Cardio Center and Transplant Center at Niguarda Hospital in Milan, said in a press release. “A small study previously indicated acute myocarditis is a rare occurrence in people infected with COVID-19. Our analysis of international data offers better insight to the occurrence of acute myocarditis during COVID-19 hospitalization, particularly before the COVID-19 vaccines were widely available.”
The researchers suspected 112 patients of having acute myocarditis and identified 97 as having possible acute myocarditis. Of those, 54 patients (median age, 38 years; 39% women) were identified has having definite or probable acute myocarditis after cardiac MRI and/or endomyocardial biopsy.
The prevalence of definite or probable acute myocarditis was 2.4 per 1,000 COVID-19 hospitalizations and the prevalence of possible acute myocarditis was 4.1 per 1,000 COVID-19 hospitalizations, Ammirati and colleagues found.
Among those with definite or probable acute myocarditis, the most common symptoms were chest pain (55.5%) and dyspnea (53.7%), according to the researchers.
In addition, of those with definite or probable acute myocarditis, 57.4% did not have COVID-19-associated pneumonia and 38.9% had fulminant myocarditis requiring inotropes or mechanical circulatory support.
The rate of in-hospital mortality or mechanical circulatory support was 20.4% in those with definite or probable acute myocarditis, the researchers wrote.
The rate of 120-day mortality was estimated at 6.6%, including 15.1% in patients with COVID-19-associated pneumonia and 0% in patients without it (log-rank P = .044), Ammirati and colleagues found.
Median left ventricular ejection fraction improved from 40% at admission to 55% at discharge (P < .0001), and the improvement did not differ in patients with and without pneumonia, the researchers wrote.
“This analysis indicates that, although rare, hospitalized patients with acute myocarditis associated with COVID-19 infection have a much greater need for intensive care unit admission, in up to 70.5% of the cases, despite the average age of the individuals in the study being much younger than expected at 38 years old,” Marco Metra, MD, a cardiology professor at the Institute of Cardiology and in the department of medical and surgical specialties, radiological sciences and public health at the University of Brescia in Italy, said in the release.
- International study finds heart inflammation rare among people hospitalized with COVID-19. newsroom.heart.org/news/international-study-finds-heart-inflammation-rare-among-people-hospitalized-with-covid-19. Published April 11, 2022. Accessed April 11, 2022.