Treatment of pulmonary artery stenosis after arterial switch operation: stent implantation vs. balloon angioplasty.

The development of pulmonary artery stenosis is a potential complication during the mid- to long-term follow-up after arterial switch operation (ASO) for transposition of the great arteries. Surgical results have been disappointing and conventional balloon dilation yields a fairly important incidence of failures and recurrences. We evaluated our results with implantation of balloon-expandable stents in 5 out of 13 patients with a previously attempted unsuccessful conventional balloon dilation of pulmonary artery branch stenosis after ASO. In two more cases, stents were used as a primary procedure. Balloon angioplasty achieved a 15% increase in mean diameter of the stenosis vs. 124% with the use of stents (P< 0.01), a 10% decrease of the pressure gradient across the stenosis vs. 71% of stents (P<0.01), and a 10% drop in RV/aorta pressure ratio vs. 43% of stents (P<0.01). Compared to conventional balloon angioplasty in our series, stents were more effective in the treatment of patients with peripheral pulmonary artery stenosis after ASO. Balloon dilation should be considered in selected cases unsuitable for treatment with endovascular stents.