Anomalous right ventricular muscle bundle: Clinical pitfalls and extracardiac anomalies

Seven patients with anomalous right ventricular muscle bundle are presented to emphasize possible pitfalls in the clinical diagnosis as based on physical examination, chest x ray, and electrocardiogram. Echocardiography, on the other hand, revealed abnormalities in all four of the patients on whom the study was done. The echocardiogram was directly responsible for a change in diagnosis and referral for a cardiac catheterization in one patient who had been followed for 19 years with the clinical diagnosis of a small ventricular septal defect.