Interventricular septal hematoma is an extremely rare complication following congenital heart surgery. During cardiac surgery, interventricular septal hematomas can be detected only by intraoperative transesophageal echocardiography. Here, we report an interesting case of interventricular septal hematoma that was accidentally found in an infant following ventricular septal defect (VSD) closure.
Transesophageal echocardiography images were acquired from a 1-month-old boy after surgical repair of a large (6.5 mm) perimembranous outlet VSD with interventricular septal flattening. Surgical correction was performed with auto-pericardium and 7-0 Prolene sutures. The patient was successfully weaned from cardiopulmonary bypass, and transesophageal echocardiography showed no VSD leakage and good ventricular function. However, approximately 30 minutes later, two anechoic masses were found within the interventricular septum, which were suspected to be interventricular septal hematomas; the larger mass measured 1.51 x 1.48cm. The swollen interventricular septum showed decreased contractility and compressed both the right and left ventricles. However, there was no change in the size of hematomas or a significant hemodynamic instability for 30 minutes of observation. Therefore, expecting spontaneous resolution of the hematomas, the interventricular septum was not explored and the patient was removed from cardiopulmonary bypass. On postoperative day 4, follow-up transthoracic echocardiography revealed thrombi filling the hematomas. The patient was discharged on postoperative day 15 and followed-up with regular echocardiographic evaluations.
We describe a unique case of interventricular septal hematoma after VSD closure. Surgical manipulation of perimembranous VSD and injury of the septal perforating artery may contribute to development of an interventricular septal hematoma. In hemodynamically stable patients, conservative treatment and serial echocardiographic evaluation generally show gradual resolution of the hematoma. Pediatric cardiac anesthesiologists should be aware of this rare complication after VSD repair.