Echocardiographic observations regarding pericardial effusions associated with cardiac disease.

Cardiac disease associated with congestive heart failure was found to be the most common cause (22 of 76) of pericardial effusion in patients referred for echocardiography. Parameters of left heart function were markedly abnormal in these patients with congestive heart failure and pericardial effusion, but were not significantly different from a group of patients with congestive heart failure without pericardial effusion. Clinical findings consistent with cardiac decompensation also failed to discern between these two groups. Nonetheless, patients with congestive heart failure with pericardial effusion had significantly larger right ventricular internal dimensions than those without effusion. Patients with pericardial effusion related to congestive heart failure (P < .01), heart disease without congestive heart failure (P < 0.001) and those patients post recent myocardial infarction (P < 0.05) had significantly larger right ventricular internal dimensions in diastole than normal subjects. Patients with pericardial effusions related to recent open heart surgery, idiopathic pericarditis or of miscellaneous causes had normal right ventricular internal dimensions. It is likely that right ventricular dilation indicates abnormal volume/pressure relationships of the right heart and that this abnormality, through alterations in venous and lymphatic drainage, underlies the accumulation of pericardial effusion in these patients with heart disease with or without congestive heart failure.