key: cord-0961091-3nwk0sbj authors: Lin, Weiqin; Yip, Alfred Chung Lum; Evangelista, Lauren Kay Mance; Wong, Raymond Ching Chiew; Tan, Huay Cheem; Lim, Toon Wei; Singh, Devinder title: Ventricular tachycardia from myocarditis following COVID‐19 vaccination with tozinameran (BNT162b2, Pfizer‐BioNTech) date: 2022-04-04 journal: Pacing Clin Electrophysiol DOI: 10.1111/pace.14486 sha: b2d75b04aceb003bf0192d65a4099748455d4c92 doc_id: 961091 cord_uid: 3nwk0sbj To combat the coronavirus disease 2019 (COVID‐19) pandemic, many countries have started population vaccination programs using messenger ribonucleic acid (mRNA) vaccines. With the widespread use of such vaccines, reports are emerging worldwide, of the vaccine's association with the development of myocarditis. Younger men are more likely to develop postvaccine myocarditis, which usually presents as self‐limiting chest pain within a week after the second dose. We present a case of myocarditis following vaccination with tozinameran (BNT162b2, Pfizer‐BioNTech), which presented late, with ventricular tachycardia (VT) reduced left ventricular ejection fraction (LVEF). The Coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has been a worldwide pandemic since end-2019, with more than 200 million cases reported by early August 2021, accounting for more than 4 million deaths to date. 1 Population vaccination has been the strategy being employed by most countries to combat the pandemic. More than 4 billion doses of COVID-19 vaccines have been administered at the time of writing, with the messenger ribonucleic acid (mRNA) vaccine tozinameran (BNT162b2, Pfizer-BioNTech, Mainz, Germany) being one of the most used vaccines worldwide due to its proven efficacy. 2, 3 However, the use of mRNA COVID-19 vaccines has been reported to be associated with the development of myocarditis. [4] [5] [6] [7] We report a case of sustained ventricular tachycardia (VT) secondary to acute myocarditis following COVID-19 vaccination in a young adult male. However, he presented again 8 days after his discharge, due to recurrent palpitations. He was found to have frequent nonsustained ventricular VT on telemetry monitoring and received an implantable cardiac defibrillator. During the defibrillation implantation procedure, endomyocardial biopsy was performed for the patient at the same setting. Histology of the myocardial tissue revealed focal hypertrophy of cardiomyocytes, with interstitial fibrosis. Immunohistochemistry with CD3 showed isolated T lymphoid cells while CD163 highlighted scattered histiocytes. This was consistent with recent/resolved myocarditis. To our knowledge, this is the first case of myocarditis related to COVID-19 mRNA vaccination that has presented with VT. There have been reports of an association between COVID-19 mRNA vaccines and myocarditis, primarily among young males within a few days after the second vaccination dose. 4 inflammation, however, resulted in residual myocardial scarring. This scarring process was detected as LGE on the CMR, fulfilling the revised Lake Louise diagnostic criteria for myocarditis. 9 His positive CMR, together with the initial symptoms, elevated cardiac troponin levels and lack of other identifiable cause for these findings, fulfilled the CDC criteria for confirmed myocarditis following COVID-19 vaccination. 10 The right superior axis, QS pattern in lateral leads with an atypical COVID-19 Weekly Epidemiological Update Edition 52 WHO Coronavirus (COVID-19) Dashboard Safety and efficacy of the BNT162b2 mRNA Covid-19 vaccine Myocarditis after BNT162b2 and mRNA-1273 vaccination Myocarditis following immunization with mRNA COVID-19 vaccines in members of the US military A series of patients with myocarditis following SARS-CoV-2 vaccination with mRNA-1279 and BNT162b2 Myocarditis temporally associated with COVID-19 vaccination Myocarditis with COVID-19 mRNA vaccines Cardiovascular magnetic resonance in nonischemic myocardial inflammation: expert recommendations Use of mRNA COVID-19 Vaccine after Reports of Myocarditis Among Vaccine Recipients: Update from the Advisory Committee on Immunization Practices -United States RBBB morphology in V1 suggests that the VT was originating from the inferolateral left ventricular wall. This correlated well with the site of delayed gadolinium enhancement on CMR. The mechanism of his monomorphic VT is likely to be scar related re-entry. Acute myocarditis is increasingly being recognized as a side effect of mRCA COVID-19 vaccination, especially in younger males. While usually presenting early with chest pain, we report a late presentation of potentially life-threatening VT. This may be due to the myocardial inflammation and edema early in the course of myocarditis, or scar related later on in the disease process, in the case of our patient. With more younger individuals expected to receive their mRNA vaccines in the coming months, heightened vigilance for this serious complication would be prudent. None for all authors. Weiqin Lin MBBS https://orcid.org/0000-0001-8319-504X