Prevalence, Clinical Course and Etiology of Viral Myocarditis in the COVID-19 Era

ABSTRACT

Background: Myocarditis is one of the most suspected etiologies in patients with unexplained heart failure (HF). We studied the in-hospital prevalence of viral myocarditis and recognize the etiologic cardiotropic viruses in patients admitted with unexplained HF during the COVID era. Method: This is a prospective observational study. We recruited patients with unexplained HF presenting at a university hospital from 1st October 2020 till 31st March 2021 (Fig.1). Patients were included if they present with unexplained acute HF associated with normal coronary angiography (CA). All patients were subjected to full history and examination, ECG, echocardiography, cardiac magnetic resonance (CMR) and CA. Sera were obtained from all suspected patients for detection of antibodies against the viruses by using ELISA and polymerase chain reaction (PCR). Results: Fifty-one patients fulfilled the inclusion criteria. 72.5% were males with mean age 39±16 years. We classified patients into 2 categories based on CMR results: Group A (CMR positive myocarditis) 12 patient (23.5%) and group B (CMR negative myocarditis) 35 (68.6%) patients. 51% of the patients presented with dyspnea, 27.5% with chest pain, 33.3% had LVEF >50%,19.6% with cardiogenic shock. 65.9% of patients (n=31/47) were associated with antibodies against the common cardiotropic viruses. Parvovirus B19 22 (46.8%) and Coxackie 16 (34%) were observed. 3 patients died at 6 months clinical follow up;91.5% from patients had recovered left ventricular ejection fraction. Conclusion: The in-hospital prevalence of myocarditis was 5 times higher in the COVID era. CMR is a good positive test for the diagnose acute myocarditis. Parvovirus B19 and Coxackie viruses represent most common pathogens in our locality. (Clinical trial registration no=NCT04312490, STDF grant no=26393 ) [Formula presented]