A 26-year-old male patient was diagnosed with an isolated recurrent intramyocardial - extracardiac hydatid cyst with pericardial protrusion after being admitted with chest pain and palpitation. He had undergone surgical resection of an intramyocardial pericardial hydatid cyst without cardiopulmonary bypass 10 years earlier. In the current admission, the results from transthoracic and transesophageal echocardiography and multislice computed tomography were confirmed by serological and histopathological tests. The cyst was excised under cardiopulmonary bypass, and the patient was treated postoperatively with albendazole for 9 months. His clinical status improved postoperatively and he was asymptomatic without signs of recurrence as determined by echocardiography. (Circ J 2008; 72: 1718 - 1720)