An hydatid cyst of the left lobe of the liver, associated with right heart failure, was diagnosed in a 61-year-old man presenting with dyspnoea. Doppler echocardiography combined with cardiac catheterization demonstrated the presence of pulmonary precapillary hypertension. Pulmonary perfusion scintigraphy with Technetium-labelled albumin microspheres demonstrated multiple pulmonary embolisms, leading to a diagnosis of postembolic chronic cor pulmonale. Due to the absence of thrombophlebitis and ultrasound signs of an intracaval hydatid membrane, floating at the level of the cyst of the left lobe of the liver, the diagnosis of parasitic postembolic chronic heart pulmonale, due to fistulization of an hepatic hydatid cyst into the inferior vena cava, was established. Only chemotherapy was proposed in this patient due to dissemination of the hydatid material in the lungs.