Myocardial injury and coronavirus-induced myocarditis in patients recovered from COVID-19-a multicenter CMR study

ABSTRACT

INTRODUCTION Coronavirus disease-2019 (COVID-19) is an emerging disease with a wide spread, multiorgan involvement beyond pulmonary manifestations and unknown cardiovascular (CV) consequences. Therefore our aim was to assess the myocardial injury in patients recovered from COVID-19 in cardiovascular magnetic resonance (CMR). MATERIAL AND METHODS This was a multicenter, prospective study involving 5 Polish CMR labs with a high and long-standing experience in CV diseases. All the consecutive patients recovered from COVID-19 (confirmed in reverse transcription polymerase chain reaction [RT-PCR] test) and scheduled for CMR due to cardiac symptoms and a clinical suspicion of myocarditis were enrolled into the study. Patients with a history of previous cardiac injury were excluded from the study. All the patients underwent a contrast-enhanced CMR with conventional myocarditis protocol, including a late gadolinium enhancement (LGE). RESULTS The study group included 250 patients (age 45 ± 12 years old;53% females) with hypertension (24%), diabetes (6%), obesity (67%) and chronic pulmonary disease (6%) sent for cardiac imaging. The main single indications were a suspicion of myocarditis (42%) or unexplained fatigue (22%) or arrhythmia (12%). Sixty patients had at least moderate COVID-19 requiring hospitalization and the CMR was performed up to 6 months after the disease with the majority of cases performed within 3 months (76%). The left ventricle (LV) function was normal in 91,5% (mean ejection fraction [EF] 62 ± 14%) with a moderate or severe dysfunction in 17 and 4 pts. The right ventricle (RV) function was normal in 85% (mean EF 56.2 ± 8%) with a borderline dysfunction (EF 45-50%) in 17 patients and dysfunction in 20 patients. The enlargement of ventricles (indexed to body surface area) was found in 19 (LV) and 7 (RV) cases. The pericardial effusion was found in 29 pts (11%) and active pericarditis in 21 cases (8%). Finally, active myocarditis and/or edema was noticed in 28 (11%) individuals and myocarditis-like LGE as a post-myocarditis injury in LV myocardium was found in 129 patients (51%). However, 79% of patients showed LGE limited to four or less segments and great majority of the injured segments (92%) revealed only a mild range of LGE (<25% of segment). There was a trend and a weak association between the time of recovery and number of injured segments (r = 0.1;P = 0.05) and no association between the number of injured segments and age (P = ns). CONCLUSIONS Half of the patients recovered from COVID-19 were found to have a myocarditis-like LGE injury in LV, mostly with limited myocardial extent and preserved systolic function. Every fifth of them revealed signs of active inflammation within perior myocardium. The long-term clinical consequences of our findings are unknown.