Long-Term Outcome of Arterial Switch Operation Conversion After Failed Senning/Mustard Procedure

Background. We evaluated long-term outcomes of the arterial switch operation (ASO) conversion after a failed Senning/Mustard operation among patients with dextro-transposition of the great arteries. Methods. Between 1986 and 2006, 9 patients with dextro-transposition of the great arteries underwent ASO conversion at our institute. All patients had systemic right ventricle failure, 6 had supraventricular tachycardia, and 8 had moderate or severe tricuspid valve regurgitation. All patients had New York Heart Association classification II or III. The median age of patients at the ASO conversion operation was 7.4 years (range, 0.6 to 32.4 years). Pulmonary artery banding for left ventricle training was performed in 8 of the 9 patients before conversion. Results. There was 1 early death from low-output syndrome at 5 days postoperatively and 1 late sudden death at 5 months. Median follow-up time was 23.1 years (range, 0.08 to 28.0 years). The actuarial survival rate was 76.1% at 20 years. Long-term survivors revealed good New York Heart Association classification (class I, 6 patients; class II, 1 patient), with less than mild tricuspid regurgitation and brain natriuretic peptide levels of 40.6 +/- 16.2 pg/mL. Cardiac catheterization revealed significant improvements of right ventricle end-diastolic volume (decreased from 243.2% to 117.7% of normal), and right ventricle ejection fraction (increased from 0.42 to 0.572; p < 0.05). Three patients underwent new pacemaker implantation for sick sinus syndrome, and moderate neoaortic valve regurgitation developed in 1 patient. Conclusions. Excellent long-term outcomes can be achieved after ASO conversion; however, careful observation for new-onset sick sinus syndrome and aortic regurgitation is mandatory. (C) 2016 by The Society of Thoracic Surgeons