Palliative Endovascular Intervention in Infants with Tetralogy of Fallot: A Case Series

Background: Endovascular stent placement in the right ventricular outflow tract (RVOT) has been an alternative to Blalock-Taussig (BT) surgery in the treatment of Tetralogy of Fallot (TOF) in symptomatic infants with low birth weight and complex anatomy. Objective: To evaluate endovascular stent placement in the RVOT as a primary treatment for infants with TOF who are not candidates for BT surgery, and evaluate medium-term outcomes until the stent is removed during corrective surgery. Methods: Six infants with TOF were treated with RVOT stenting from October 2015 to April 2018. Hemodynamic parameters were compared between the pre- and post-stenting periods. Results: At the time of stenting, participants had a median age and weight of 146.5 days and 4.9 kg, respectively. Peak systolic gradient decreased from 63.5 mm Hg to 50.5 mm Hg, while the diameter of the left and right pulmonary arteries increased from 3.5 mm to 4.9 mm and 4.3 mm, respectively. The Nakata index increased from 96.5 mm to 108.3 mm; weight increased from 4.9 kg to 5.5 kg; and oxygen saturation, from 83.5% to 93%. There was one case of stent migration and two deaths, one caused by stent embolization and the other unrelated to study procedures. Conclusions: RVOT stenting is a promising alternative for the palliative treatment of TOF in infants with low birth weight and complex anatomy.