An 87-year-old woman was admitted to our hospital on an emergency basis with atypical chest pain and dyspnea. She had a continuous precordial murmur. Electrocardiogram showed no evidence of myocardial ischemia, but chest X-ray showed marked enlargement of the cardiac silhouette and an abnormal calcified vascular structure. Computed tomography of the chest revealed large abnormal masses next to the heart. Two-dimensional echocardiography showed enlargement of the main trunk of the left coronary artery and 2 giant saccular aneurysms. Abnormal diastolic inflow to the main pulmonary trunk was also observed by color flow imaging. These findings were supported by data obtained using magnetic resonance imaging and transesophageal echocardiography. Based on the above findings, we diagnosed this case as a coronary artery fistula originating from the proximal left anterior descending artery associated with 2 giant saccular aneurysms draining into the pulmonary artery. To our knowledge, this is the oldest patient ever reported with such an anomaly. This case emphasizes that a good prognosis is possible even with a very pronounced visible structural abnormality. (Jpn Circ J 1996; 60: 618 - 623)