Evaluation of Residual Right Ventricular Outflow Tract Obstruction After Pulmonary Valve-Sparing Repair of Tetralogy of Fallot: An Echocardiographic Study

Background: Pulmonary valve-sparing repair (PVSR) of Tetralogy of Fallot (TOF) provides good results in selected patients. However, recurrent right ventricular outflow tract obstruction (RVOTO) can occur requiring surgical revision. We sought to evaluate the course of RVOTO after PVSR by serial echocardiographic (ECHO) assessment. Methods: A retrospective analysis was conducted in patients who underwent PVSR of TOF at our institution. Demographic, anatomical, surgical and 2D-ECHO data were collected. The cohort was divided into two groups: no reintervention group (group 1) and reintervention group (group 2). Results: Ninety-one patients were included in this study; 13 patients (14%) required reintervention. Right ventricular outflow tract ECHO peak gradient was significantly higher in group 2 at intraoperative transesophageal ECHO (iTEE) (P = .009), at hospital discharge (P = .021), at six months follow-up (P = .0001) and 12 to 36 months follow-up (P = .0001). A more prevalent subvalvular stenosis was found in group 2 at six months (P = .0011) and 12 to 36 months follow-up (P = .00069). An RVOT ECHO peak gradient of 30 mm Hg at iTEE (P = .025) and discharge (P = .011) was statistically associated with the need for reintervention. Conclusions: Right ventricular outflow tract peak gradient was significantly higher in group 2 than in group 1 at iTEE, discharge and follow-up, with an ECHO peak gradient of 30 mm Hg being predictive of reintervention At follow-up, residual RVOTO was prevalent at the subvalvular level in group 2. This information will be useful in clinical decision-making for TOF patients undergoing pulmonary valve sparing repair.