10th May 2025

Complications

Generally, most people with myocarditis recover and inflammation spontaneously recovers with conservative treatment. Falling inflammatory markers and cardiac biomarkers are suggestive of recovery. Patients are recommended to follow up with a Cardiologist and CMR follow-up is recommended in patients with persistent dysfunction at echocardiography, arrhythmias or ECG abnormalities at this review.

It takes at least 3 months before CMR signs of oedema (secondary to inflammation in the acute phase/baseline) disappear. At 6 months, T1 or T2 signs of oedema should have disappeared if inflammation would be completely absent. Still, the absence of T1 or T2 oedema does not exclude chronic low-grade inflammation.

Yearly follow-up for at least 4 years, with an ECG and echocardiography, is recommended by the ESC as acute myocarditis may lead to dilated cardiomyopathy (DCM) in up to 20% of cases. In those with significantly impaired left ventricular ejection fraction (LVEF) at the time of hospital admission has been shown to be a poor prognostic marker. 

However, the prognosis can vary widely depending on aetiology, with giant-cell myocarditis being associated with the poorest prognosis, an approximately 90% rate of death or cardiac transplantation and a median survival of 5.5 months from symptom onset.