Incidentally Discovered Cor Triatriatum Sinistrum Anomaly During Heart Transplant.

Physicians incidentally discovered cor triatriatum sinistrum (CTS) during heart transplant in a 51-year-old male patient who experienced heart failure resulting from ischemic cardiomyopathy. His medical history was remarkable for coronary stenting and coronary artery bypass grafting. Echocardiography revealed a band-like structure in the left atrium (Fig. 1). A suitable donor was available, and the patient successfully underwent orthotopic heart transplant. During explantation of the native heart, CTS was discovered as a semicircular membrane (septation) within the left atrium (forceps) (Fig. 2). The CTS was completely excised, and careful inspection of the pulmonary veins and both superior and inferior vena cavae showed no anomalies. The postoperative course was uneventful, and the patient was discharged from the hospital on postoperative day 13.Cor triatriatum sinistrum is an abnormal septation within the left atrium with an incidence of 0.1% to 0.4% in patients with congenital cardiac disease.1 Cor triatriatum sinistrum is usually associated with other cardiac anomalies, including atrial septal defect, left superior vena cava, and anomalous pulmonary venous return.2 Symptoms typically mimic mitral stenosis, and resection is the standard treatment for symptomatic patients.3Although CTS is a rare congenital cardiac anomaly, adult cardiac surgeons should be aware of potential associated anomalies, especially left superior vena cava and anomalous pulmonary venous return, during heart transplant procedures.