[A case report of cor triatriatum benefit of MRI for preoperative diagnosis and surgical method].

Cor triatriatum is uncommon in all congenital heart diseases. It is a malformation resulting in a separation of the left atrium or right atrium into two chambers due to a congenitally abnormal diaphragm. We wish to present a case of cor triatriatum in which MRI was found most useful for preoperative diagnosis and surgical procedure. A 2-year-old girl was transferred to us for severe pulmonary congestion as shown on chest X-ray. Echocardiography showed abnormal diaphragm in the left atrium. MRI demonstrated clearly the relationship between left pulmonary vein and the abnormal diaphragm. Therefore we should preoperatively determine type I A according to the Lucas and Schmidt's classification. Cardiac catheterization showed moderate pulmonary hypertension and confirmed cor triatriatum. The resection of the abnormal diaphragm was performed under extracorporeal circulation with moderate hypothermia. The postoperative course was uneventful. MRI is a very useful non-invasive technique in making a diagnosis and in choosing the appropriate surgical procedure for cor triatriatum.