Echocardiographic studies of left ventricular function were carried out in 20 patients with chronic unspecific pulmonary diseases (CUPD). These patients showed no true left ventricular myocardial hypertrophy, while electrocardiographic signs of the latter might be related to the recording of potentials from the hypertrophic ventricular septum produced by positional cardiac changes due to pulmonary emphysema. In addition to septal hypertrophy, end diastolic left ventricular size was shown to be diminished. A hypothesis is proposed for the pathogenesis of left ventricular pumping disorders associated with CUPD.