Impact of aortic annular size on rate of reoperation for left ventricular outflow tract obstruction after repair of interrupted aortic arch and ventricular septal defect.

BACKGROUND

The neonatal repair of interrupted aortic arch and ventricular septal defect (IAA/VSD) presents a surgical challenge. Although one-stage repair has become well established, left ventricular outflow tract obstruction (LVOTO) continues to be an important factor affecting survival and reintervention rates after IAA/VSD repair. We investigated the relationship between the preoperative aortic annulus and the rates of reoperation for LVOTO.

METHODS

Between July 1994 and July 2006, 38 patients with IAA/VSD have undergone complete single-stage repair. Patients with single ventricle physiology, transposition of the great arteries, or truncus arteriosus were excluded. Surgical technique involved the aortic arch reconstruction and VSD closure. Three patients underwent subaortic resection at the time of first operation and one patient underwent Yasui operation. The patients were divided into two groups according to whether the aortic annulus is greater than the patient's weight (kg) + 1.5 mm or less.

RESULTS

The average follow-up was 7.9 +/- 4.2 years. Among the patients with small aortic annulus (n = 12), there was one hospital death and 6 reoperations for LVOTO, and one late death. There was only one reoperation for LVOTO among the patients with larger aortic annulus (n = 26, p < 0.001). The patients whose aortic annulus is less than patient's weight (kg) + 1.0 mm had poor outcomes if the LVOTO is not addressed at the time of the first operation.

CONCLUSIONS

Neonatal single-stage repair for IAA/VSD achieves excellent survival. For the patients whose aortic annulus is greater than patient's weight (kg) + 1.5 mm, low reoperation rate for LVOTO is expected. For the patient whose aortic annulus is less than patient's weight + 1.5 mm, almost half of them needed reoperation. An LVOT bypass procedure (Yasui or Norwood) is recommended if the aortic annulus is less than the patient's weight + 1.0 mm.