Results of the Double Switch Operation in Patients Who Previously Underwent Left Ventricular Retraining

Background Congenitally corrected transposition of the great arteries (CC-TGA) is a complex form of congenital heart disease that has numerous subtypes. While most patients with CC-TGA have a large ventricular septal defect (VSD) and pulmonary stenosis, there are some patients who have either no VSD or a highly restrictive VSD. These patients will require left ventricular (LV) retraining prior to double switch. The purpose of this study was to review our experience with the double switch procedure in patients who had previously undergone LV retraining.Methods This was a retrospective review of a single institution experience with the double switch procedure in patients who had undergone LV retraining (2002-present).Results Forty-five patients underwent double switch following LV retraining. Of these, 39 had an arterial switch with hemi-Mustard/bidirectional Glenn and six had a Senning. The median cross-clamp time was 135 min (range 71-272) and median bypass time was 202 min (range 140-430 min). Median hospital length of stay was eight days (range 4-108). There were no in-hospital deaths. Median duration of follow-up was 30 months (range 0-175). One patient subsequently underwent heart transplantation and died 65 months following double switch. At follow-up, 41 of the 44 survivors (93%) have normal or low normal LV function and 40 of the 44 survivors (91%) have no or trace mitral regurgitation.Conclusions The data demonstrate early and mid-term survival of 100% and 97%. Ninety-three percent had preserved LV function. These results suggest that patients with CC-TGA who undergo LV retraining and double switch can have excellent clinical outcomes.