Acute Lymphocytic Myocarditis in a Young Male Post-COVID-19

Table 1

Time	Events
Day 1	1-month history of increasing fatigue, palpitations, and shortness of breath
	12-lead electrocardiogram showed an atrial tachycardia with 127 bpm. Transthoracic echocardiogram showed a severely impaired biventricular systolic function with an estimated left ventricular ejection fraction of 18%. After excluding intraventricular thrombus formations, electric cardioversion could restore sinus rhythm.
Day 2	Coronary angiography showed normal coronary arteries. Left ventricular endomyocardial biopsy was performed.
Day 2	Transfer to intermediate care unit and optimization of medical heart failure therapy.
Day 8	Cardiac magnetic resonance imaging confirmed a severely reduced left ventricular function. Increased signaling of the interventricular myocardium and strong midmyocardial late gadolinium enhancement (LGE) was noticeable. LGE was evident also in the right ventricle.
Day 13	Histology and immunohistology of the endomyocardial biopsies revealed an acute lymphocytic myocarditis. RT-PCR revealed no infection with common cardiotropic viruses. Immunosuppressive therapy with prednisolone was initiated (1 mg/kg/day) in combination with azathioprine 300 mg/day.
Day 15	Patient was equipped with a LifeVest®.
Day 17	Documentation of a non-sustained ventricular tachycardia.
Day 20	Patient was discharged on a steroid taper in combination with azathioprine 300 mg/day.
Follow-up at 3 months	Follow-up cardiac magnetic resonance imaging was performed on an outpatient basis. An improved LV systolic function with an estimated LV ejection fraction of 36% was evident, and a strong LGE was still detectable.