Left Ventricular Retraining and Late Arterial Switch for d-Transposition of the Great Arteries

Ann Thorac Surg. 2015 May;99(5):1655-63. doi: 10.1016/j.athoracsur.2014.12.084. Epub 2015 Mar 24.

Left Ventricular Retraining and Late Arterial Switch for d-Transposition of the Great Arteries.

Watanabe N1Mainwaring RD2Carrillo SA1Lui GK3Reddy VM1Hanley FL1.

Comment: In this paper, the outcomes of 32 patients who presented with systemic RV failure (NYHA class 3 or 4) and were evaluated to undergo a late arterial switch operation (ASO) after LV retraining are described. In 7 out of 32 patients late ASO was performed directly as their LV already performed under high pressures. 12 out of 25 patients who underwent LV retraining using stepwise pulmonary artery banding did not fulfill criteria needed to undergo a late arterial switch. Out of 20 patients who underwent the late arterial switch operation, 2 patients died perioperatively and 2 early after surgery due to LV systemic failure. In addition, neo-aortic valve reoperations or complications were common in long-term arterial switch survivors.

These findings illustrate the potential value and the risks of the late arterial switch operation in patients with systemic RV failure. Although LV retraining had a limited success rate and the ASO was associated with considerable perioperative and early postoperative mortality rates, the subgroup of patients that survived after the arterial switch did have less symptoms and their improved hemodynamic status may allow prolonged survival. The authors finally also described their institutional protocol for these patients, which became more strict as their experience increased.  Interestingly, age was not a predictor for successful LV retraining, suggesting the late arterial switch is still an option for older patients. This study did not report imaging data before or after LV retraining and the subsequent arterial switch. More details regarding the predictors of success may allow better selection of patients for these high-risk procedures.