ABSTRACT
Introduction: Although myocarditis after anti-SARS-CoV-2 vaccination is increasingly recognized, we have little data regarding the course of the disease and, consequently, the imaging findings, including the tissue-specific features. The purpose of this study is to describe the clinical, immunological, and cardiac magnetic resonance (CMR) features of myocarditis after COVID-19 immunization in the acute phase and during follow-up. We aimed to compare the trajectory of the disease to myocarditis cases unrelated to COVID-19. Methods: We assembled a CMR-based registry of potentially COVID-19 vaccination-related myocarditis cases. All patients who experienced new-onset chest pain and troponin elevation after COVID-19 vaccination and imaging confirming the clinical suspicion of acute myocarditis were enrolled in our study. Participants underwent routine laboratory testing and testing of their humoral and cellular immune response to COVID-19 vaccination. Clinical and CMR follow-up was performed after 3-6 months. We included two separate, sex- and age-matched control groups: (1) individuals with myocarditis unrelated to COVID-19 infection or vaccination confirmed by CMR and (2) volunteers with similar immunological exposure to SARS-CoV-2 compared to our group of interest (no difference in the number of doses, types and the time since anti-SARS-CoV-2 vaccination and no difference in anti-nucleocapsid levels). Results: We report 16 CMR-confirmed cases of myocarditis presenting (mean ± SD) 4 ± 2 days after administration of the anti-SARS-CoV-2 vaccine (male patients, 22 ± 7 years), frequently with predisposing factors such as immune-mediated disease and previous myocarditis. We found that 75% received mRNA vaccines, and 25% received vector vaccines. During follow-up, CMR metrics depicting myocardial injury, including oedema and necrosis, decreased or completely disappeared. There was no difference regarding the CMR metrics between myocarditis after immunization and myocarditis unrelated to COVID-19. We found an increased T-cell response among myocarditis patients compared to matched controls (p < 0.01), while there was no difference in the humoral immune response. Conclusion: In our cohort, myocarditis occurred after both mRNA and vector anti-SARS-CoV-2 vaccination, frequently in individuals with predisposing factors. Upon follow-up, the myocardial injury had healed. Notably, an amplified cellular immune response was found in acute myocarditis cases occurring 4 days after COVID-19 vaccination.
ABSTRACT
INTRODUCTION: Based on recently published randomized controlled trials, cardiac contractility modulation (CCM) seems to be an effective device-based therapeutic option in symptomatic chronic heart failure (HF) (CHF). The aim of the current study was to estimate what proportion of patients with CHF and left ventricular ejection fraction (LVEF) <50% could be eligible for CCM based on the inclusion criteria of the FIX-HF-5C trial. METHODS: Consecutive patients referred and followed up at our HF clinic due to HF with reduced or mid-range LVEF were retrospectively assessed. After a treatment optimization period of 3-6 months, the inclusion criteria of the FIX-HF-5C trial (New York Heart Association (NYHA) class III/IV, 25% ≤ LVEF ≤45%, QRS <130 ms, and sinus rhythm) were applied to determine the number of patients eligible for CCM. RESULTS: Of the 640 patients who were involved, the proportion of highly symptomatic patients in NYHA class III/IV decreased from 77.0% (n = 493) at baseline to 18.6% (n = 119) after the treatment optimization period (p < 0.001). Mean LVEF increased significantly from 29.0 ± 7.9% to 36.3 ± 9.9% (p < 0.001), while the proportion of patients with 25% ≤ LVEF ≤45% increased from 69.7% (n = 446) to 73.3% (n = 469) (p < 0.001). QRS duration was below 130 ms in 63.1% of patients, while 30.0% of patients had persistent or permanent atrial fibrillation. We found that the eligibility criteria for CCM therapy based on the FIX-HF-5C study were fulfilled for 23.0% (n = 147) of patients at baseline and 5.2% (n = 33) after treatment optimization. CONCLUSION: This single-center cohort study showed that 5% of patients with CHF and impaired LVEF immediately after treatment optimization fulfilled the inclusion criteria of the FIX-HF-5C study and would be candidates for CCM.
