Recurrent pulmonary embolism due to hydatid disease of heart. Study of 3 cases, one with intermittent tricuspid valve obstruction (atrial pseudomyxoma).

Three cases of pulmonary hypertension caused by hydatid emboli from the right side of the heart are described; cardiac catheterisation was performed in 2. One case was confirmed at operation and 2 at necropsy. The pulmonary emboli were caused by hydatid vesicles in all 3 cases and in none was there pulmonary thrombosis; free scolices were found in the pulmonary alveoli in 2. In 1 patient with repeated syncopal attacks there was a pedunculated cyst in the right atrium which was though to have intermittently obstructed the tricuspid valve. Gamma radiography, angiocardiography, and necropsy suggested a mechanical cause for the pulmonary hypertenion with no vasoconstrictive element. The surgical patient was alive and well 18 months later.