Fulminant myocarditis following SARS-CoV-2 mRNA vaccination rescued with venoarterial ECMO: A report of two cases.

INTRODUCTION: Cases of myocarditis after COVID-19 messenger RNA (mRNA) vaccines administration have been reported. Although the majority follow a mild course, fulminant presentations may occur. In these cases, cardiopulmonary support with venoarterial extracorporeal membrane oxygenation (V-A ECMO) may be needed. RESULTS: We present two cases supported with V-A ECMO for refractory cardiogenic shock due to myocarditis secondary to a mRNA SARS-CoV2 vaccine. One of the cases was admitted for out-of-hospital cardiac arrest. In both, a peripheral V-A ECMO was implanted in the cath lab using the Seldinger technique. An intra-aortic balloon pump was needed in one case for left ventricle unloading. Support could be successfully withdrawn in a mean of five days. No major bleeding or thrombosis complications occurred. Whereas an endomyocardial biopsy was performed in both, a definite microscopic diagnosis just could be reached in one of them. Treatment was the same, using 1000mg of methylprednisolone/day for three days. A cardiac magnetic resonance was performed ten days after admission, showing a significant improvement of the left ventricular ejection fraction and diffuse oedema and subepicardial contrast intake in different segments. Both cases were discharged fully recovered, with CPC 1. CONCLUSIONS: COVID-19 vaccine-associated fulminant myocarditis has a high morbidity and mortality but presents a high potential for recovery. V-A ECMO should be established in cases with refractory cardiogenic shock during the acute phase.

Echocardiographic assessment of COVID19 sequelae in survivors with elevated cardiac biomarkers.

AIMS: We sought to determine, using advanced echocardiography, the prevalence and type of cardiovascular sequelae after COVID19 infection with marked elevation of cardiovascular biomarkers (CVB), and their prognostic implications. METHODS: All patients admitted from March 1st to May 25th, 2020 to a tertiary referral hospital were included. Those with cardiovascular diseases or dead during admission were excluded. Patients with hs-TnI > 45 ng/L, NT-proBNP>300 pg/mL, and D-dimer >8000 ng/mL were matched with COVID controls (three biomarkers within the normal range) based on intensive care requirements and age, and separately analyzed. RESULTS: From 2025 patients, 80 patients with significantly elevated CVB and 29 controls were finally included. No differences in baseline characteristics were observed among groups, but elevated CVB patients were sicker. Follow-up echocardiograms showed no differences among groups regarding LVEF and only slight differences between groups within the normal range. Hs-TnI patients had lower myocardial work and longitudinal strain. The presence of an abnormal echocardiogram was more frequent in the elevated CVB group compared to controls (23.8 vs 10.3%, P = 0.123) but mainly associated with mild abnormalities in deformation parameters. Management did not change in any case and no major cardiovascular events except deep vein thrombosis occurred after a median follow-up of 7 months. CONCLUSION: Minimal abnormalities in cardiac structure and function are observed in COVID19 survivors without previous cardiovascular diseases who presented a significant CVB rise at admission, with no impact on patient management or short-term prognosis. These results do not support a routine screening program after discharge in this population.