Surgical repair of Tetralogy of Fallot following primary palliation: Right ventricular outflow track stenting versus modified Blalock-Taussig shunt

BACKGROUND: Tetralogy of Fallot (TOF) is a cyanotic disease requiring early intervention. We assessed the effect of right ventricular outflow tract (RVOT) stenting versus modified Blalock-Taussig shunt (mBTS) on outcomes of surgical repair of TOF. METHODS: Fifteen palliated TOF infants underwent complete repair surgery. RVOT stenting was performed in seven infants and mBTS was done in eight infants. Data on sequential patients who underwent surgery were collected and reviewed retrospectively. RESULTS: Stenting group were significantly younger (1.62 ± 0.34 vs 2.80 ± 0.52, p = 0.001), had lower body weight (3.28 ± 0.48 vs 5.03 ± 0.67, p = 0.001) and lesser body surface area (0.20 ± 0.01 vs 0.26 ± 0.20, p = 0.001) than the mBTS group at palliation. Mean right pulmonary artery (RPA) diameter in stenting group at palliation was 2.9 ± 0.54 mm (z-score -3.08 ± 0.97) and increased at surgery to 4.6 ± 0.49 mm (z-score –0.79 ± 0.66) (p = 0.001). The mean left pulmonary artery (LPA) diameter was 2.5 ± 0.42 mm (z-score -3.3 ± 0.86), which increased to 3.3 ± 0.40 mm (z-score -2.2 ± 0.74) at surgery (p = 0.005). The mean RPA diameter in mBTS group at palliation was 3.2 ± 0.32 mm (z-score –2.9 ± 0.70) and increased at surgery to 4.3 ± 0.55 mm (z-score –1.1 ± 0.94) (p = 0.001). The mean LPA diameter was 2.8 ± 0.26 mm (z-score -3.3 ± 0.62), which increased to 3.2 ± 0.24 mm (z-score –2.4 ± 0.52) at surgery (p = 0.032). Repeat echocardiography showed significant increase in McGoon ratio and Nakata index in both groups (p = 0.001). No significant differences were seen between the two groups regarding surgical procedure and postoperative complications. CONCLUSION: RVOT stenting is a safe and effective approach instead of mBTS in hazardous TOF infants with hypercyanotic spell, small PAs and complex anatomies.