Long-term follow-up of electrocardiographic findings in patients with acute myocarditis proven by endomyocardial biopsy.

Sixteen cases of acute myocarditis, proven by endomyocardial biopsy, of possible viral origin which were described in a previous paper have been followed up for up to 5 years. The cases were divided into 3 groups according to the electrocardiographic (ECG) patterns: with conduction disturbance at the early stage (Group I, 9 cases), without conduction disturbance (Group II, 4 cases); early death cases in which the follow-up could not be carried out (Group III, 3 cases). In Group I, 2 cases revealed persistent complete A-V block, 4 showed incomplete recovery of right bundle branch and/or fascicular blocks, and 3 showed complete recovery of the ECG abnormalities. In Group II, all 4 cases showed a pseudoinfarction pattern which consisted of abnormal Q waves, poor R wave progression and ST elevation. These findings disappeared during the follow-up period. All patients of Groups I and II are still alive after a follow-up period of up to 5 years.