Surgery following primary right ventricular outflow tract stenting for Fallot's Tetralogy and variants: rehabilitation of small pulmonary arteries†

Abstract

OBJECTIVES: Primary surgical repair of Tetralogy of Fallot (ToF) in small infants with small pulmonary arteries (PAs) or complex anatomies can be hazardous. We assessed the effect of right ventricular outflow tract (RVOT) stenting on subsequent surgical intervention with attention to growth of the PAs. METHODS: Primary RVOT stenting was performed in 32 symptomatic patients with ToF physiology. Twenty patients had surgical intervention, with 15 undergoing complete repair to date. Median age at stenting was 61 (range 8-406) days, and median weight, 3.9 (range 1.8-12.2) kg. RESULTS: Stenting improved saturations from 72 ± 8 to 92 ± 2% (P < 0.001). Four patients required early surgical palliation for persistent desaturation (within 4 weeks). Twenty patients went on to have surgical intervention at a median time of 220 days after stenting. There was no operative mortality after complete repair. Removing the stent lengthened the procedure time and 86% required transannular patch (TAP; bypass time 109 ± 42 min, cross clamp 68 ± 29 min). Median intensive therapy unit stay was 2 days. There was 1 late death at 3 months due to chronic lung disease. The median left PA Z-score increased from a preinterventional value of -1.27 (-0.19 to -2.87) to a presurgical value of +0.11 (-4.12 to +1.97). The median right PA Z-score increased from -2.02 (-1.77 to -4.68) to -0.65 (-0.29 to -2.04) over the preinterventional and presurgical time intervals. Growth was greatest in the right PA. CONCLUSIONS: Primary RVOT stenting facilitates staged palliation for ToF in small infants and complex anatomies. Improved PA blood flow generated by the stent leads to growth of the branch PAs and may improve the substrate for subsequent surgical repair. Surgery is safe; however, the majority will require a TAP.