Early spontaneous recovery of left ventricular function in patients with myocarditis

The natural history of myocarditis is varied. We describe 6 out of a cohort of 15 consecutive patients with histopathologic evidence of myocarditis who showed a remarkable early symptomatic and spontaneous recovery of left ventricular systolic function. The left ventricular ejection fraction increased to > or = 50% at discharge, and this improvement was maintained at late follow-up. The other 9 patients, despite clinical improvement, were not thought to have spontaneous recovery. Neither clinical severity of the illness (NYHA functional class) nor left ventricular ejection fraction at presentation demonstrated any difference in the two groups. By contrast, a smaller left ventricular internal diameter at end-diastole and a smaller left atrial dimension as determined by transthoracic echocardiography were predictive of spontaneous recovery. Firstly, we confirm that the natural history of myocarditis is indeed varied with the possibility of early spontaneous recovery; secondly we suggest that left ventricular internal diameter at end-diastole and left atrial dimension may have prognostic implications in this disease.