Intrapulmonary shunting in primary pulmonary hypertension: an observation in two patients treated with epoprostenol sodium.

Continuous intravenous infusion of epoprostenol sodium in selected patients with primary pulmonary hypertension improves symptoms and survival. This report describes two patients with primary pulmonary hypertension treated with epoprostenol in whom intrapulmonary shunting and severe hypoxemia occurred. Intrapulmonary shunting was confirmed by contrast echocardiography showing delayed appearance of bubbles in the left cardiac chambers after peripheral venous injection of agitated saline solution.