Abstract
A 66-year-old man was referred to our department for detailed examination of a tumor found at the apical site of the heart during investigation for chest pain. Computed tomography (CT) demonstrated a 38×32 mm, low-density tumor adjacent to the left ventricle. Magnetic resonance imaging (MRI) revealed the tumor with a low signal intensity in T1-weighted images and a high signal intensity in T2-weighted images without the enhancement of contrast medium. The tumor was initially diagnosed as a pericardial cyst based on the findings described above. Although it remained asymptomatic, the size of the tumor had gradually increased nine months after the first diagnosis. Video-assisted thoracic surgery (VATS) was planned to resect the tumor. Since no lesion was found on the pericardium via a thoracoscopic survey, intraoperative ultrasonography prior to incision of the pericardial sac was adopted to ensure that the mass actually was an intrapericardial cyst. In the pericardial cavity, we found a cyst firmly attached to the apical epicardium. Subtotal resection was selected to avoid damage to the ventricular muscles. The cyst wall had a lining of ciliated epithelium without smooth muscles or bronchial glands and was pathologically diagnosed as a bronchogenic cyst.
