Background: Acute myocarditis (AM) is thought to be a rare cardiovascular complication of COVID-19, although minimal data are available beyond case reports. We aim to report the prevalence, baseline characteristics, in-hospital management, and outcomes for patients with COVID-19–associated AM on the basis of a retrospective cohort from 23 hospitals in the United States and Europe. Methods: A total of 112 patients with suspected AM from 56 963 hospitalized patients with COVID-19 were evaluated between February 1, 2020, and April 30, 2021. Inclusion criteria were hospitalization for COVID-19 and a diagnosis of AM on the basis of endomyocardial biopsy or increased troponin level plus typical signs of AM on cardiac magnetic resonance imaging. We identified 97 patients with possible AM, and among them, 54 patients with definite/probable AM supported by endomyocardial biopsy in 17 (31.5%) patients or magnetic resonance imaging in 50 (92.6%). We analyzed patient characteristics, treatments, and outcomes among all COVID-19–associated AM. Results: AM prevalence among hospitalized patients with COVID-19 was 2.4 per 1000 hospitalizations considering definite/probable and 4.1 per 1000 considering also possible AM. The median age of definite/probable cases was 38 years, and 38.9% were female. On admission, chest pain and dyspnea were the most frequent symptoms (55.5% and 53.7%, respectively). Thirty-one cases (57.4%) occurred in the absence of COVID-19–associated pneumonia. Twenty-one (38.9%) had a fulminant presentation requiring inotropic support or temporary mechanical circulatory support. The composite of in-hospital mortality or temporary mechanical circulatory support occurred in 20.4%. At 120 days, estimated mortality was 6.6%, 15.1% in patients with associated pneumonia versus 0% in patients without pneumonia ( P =0.044). During hospitalization, left ventricular ejection fraction, assessed by echocardiography, improved from a median of 40% on admission to 55% at discharge (n=47; P <0.0001) similarly in patients with or without pneumonia. Corticosteroids were frequently administered (55.5%). Conclusions: AM occurrence is estimated between 2.4 and 4.1 out of 1000 patients hospitalized for COVID-19. The majority of AM occurs in the absence of pneumonia and is often complicated by hemodynamic instability. AM is a rare complication in patients hospitalized for COVID-19, with an outcome that differs on the basis of the presence of concomitant pneumonia.

Background: A significant number of heart failure (HF) patients with reduced left ventricular ejection fraction (LVEF) experience ventricular function recovery during follow-up. We studied the variables associated with LVEF recovery in patients treated with sacubitril/valsartan (SV) in clinical practice. Methods: We analyzed data from a prospective and multicenter registry including 249 HF outpatients with reduced LVEF who started SV between October 2016 and March 2017. The patients were classified into 2 groups according to LVEF at the end of follow-up (>35%: group R, or ≤35%: group NR). Results: After a mean follow-up of 7 ± 0.1 months, 62 patients (24.8%) had LVEF >35%. They were older (71.3 ± 10.8 vs. 67.5 ± 12.1 years, p = 0.025), and suffered more often from hypertension (83.9 vs. 73.8%, p = 0.096) and higher blood pressure before and after SV (both, p < 0.01). They took more often high doses of beta-blockers (30.6 vs. 27.8%, p = 0.002), with a smaller proportion undergoing cardiac resynchronization therapy (14.8 vs. 29.0%, p = 0.028) and fewer implanted cardioverter defibrillators (ICD; 32.8 vs. 67.9%, p < 0.001), this being the only predictive variable of NR in the multivariate analysis (OR 0.26, 95% CI 0.13–0.47, p < 0.0001). At the end of follow-up, the mean LVEF in group R was 41.9 ± 8.1% (vs. 26.3 ± 4.7% in group NR, p < 0.001), with an improvement compared with the initial LVEF of 14.6 ± 10.8% (vs. 0.8 ± 4.5% in group NR, p < 0.0001). Functional class improved in both groups, mainly in group R (p = 0.035), with fewer visits to the emergency department (11.5 vs. 21.6%, p = 0.07). Conclusions: In patients with LVEF ≤35% treated with SV, not carrying an ICD was independently associated with LVEF recovery, which was related to greater improvement in functional class.