Intramural Ventricular Septal Defect is a Distinct Clinical Entity Associated with Postoperative Morbidity in Children after Repair of Conotruncal Anomalies
Background—Intramural ventricular septal defects (VSDs) are interventricular communications through right ventricular free wall trabeculations that can occur after repair of conotruncal anomalies. We assessed the prevalence of residual intramural VSDs and their effect on postoperative course.
Methods and Results—Children who underwent biventricular repair of a conotruncal anomaly from 1/1/06 to 6/30/13 and had a post-operative transthoracic echocardiogram were included. Images were reviewed for residual intramural or non-intramural VSDs. The primary outcome was a composite of mortality, extracorporeal membrane oxygenation (ECMO) use, and need for subsequent catheter or surgical VSD closure. The secondary outcome was post-operative hospital length of stay (PLOS). A residual VSD was present in 256 of the 442 subjects (58%), of which 231 (90%) were <2mm in size. Forty-nine (11%) had intramural VSDs and 207 (47%) had non-intramural VSDs. Patients with intramural VSDs were more likely to reach the primary composite outcome compared to those with non-intramural VSDs or no residual VSD (14/49 [29%] vs 15/207 [7%] vs 6/186 [3%], p<0.0001). In addition, those with intramural VSDs had longer PLOS compared to those with non-intramural VSDs or no residual VSD (20 days [IQR 11-42] vs 7 days [5-14] vs 6 [4-11], p=0.0001). These associations remained significant after adjusting for known risk factors for poor outcomes, including residual VSD size and operative complexity.
Conclusions—Among residual VSDs after repair of conotruncal anomalies, intramural VSDs are uniquely associated with postoperative morbidity, mortality, and longer PLOS. It is important to recognize intramural VSDs in the postoperative period.
- Received April 29, 2015.
- Revision received July 6, 2015.
- Accepted July 30, 2015.