• A patient with primary pulmonary hypertension showed unusual echocardiographic findings. These included echoes arising from an intracavitary right ventricular muscle band mimicking a divided interventricular septum. The hemodynamic study excluded subvalvular right ventricular obstruction. Severe right ventricular hypertrophy was also present. Both findings were probably related and may possibly be found in similar cases with severe right ventricular hypertrophy, especially due to primary pulmonary hypertension. The right ventricular muscle band possibly represented hypertrophied moderator band.
(Arch Intern Med 1983;143:820-822)