Myocardial thickening in children with acute myocarditis.

Two-dimensional echocardiography showed myocardial thickening in 3 of 16 acute myocarditis patients in childhood. In all 3 cases, this myocardial thickening was transient and diminished within 3 weeks. This myocardial thickening was most marked at a few days after the onset; the interventricular septal thickness for each case was 13, 24, and 12 mm and the left ventricular posterior wall thickness was 13, 24, and 10 mm for each case. Two-dimensional echocardiography also revealed contraction disturbances in these three cases at their onset, which improved with the diminution of myocardial thickening. The contraction disturbance in acute myocarditis, occasionally causing cardiac pump failure, seems closely related to this myocardial thickening.