Abstract 12795: Impact of Right Ventricular Outflow Tract Obstruction on Right Ventricular Remodeling and Exercise Capacity in Patients With Severe Pulmonary Regurgitation After Repair of Tetralogy of Fallot
Introduction: The long-term impact of right ventricular outflow tract obstruction (RVOTO) in patients with severe pulmonary regurgitation after repair of tetralogy of Fallot are controversial.
Hypothesis: We hypothesize that patients with combined PR and RVOTO have better RV remolding and exercise capacity than patients with isolated PR.
Methods: This is a retrospective cohort study of ninety-one consecutive patients with severe PR detected on echocardiography and evaluated with cardiac magnetic resonance and cardiopulmonary exercise test between 2012 and 2016. Twenty-three patients had combined PR and RVOTO (Doppler peak RVOT gradient ≥30 mmHg), while the other had isolated PR (n=68).
Results: In spite of similar PR fraction between the two groups, patients with combined PR and RVOTO had significantly smaller RV end-diastolic volume (129.1 ± 32.7 vs 163.3 ± 53.9 ml/m2, p=0.020) and RV end-systolic volume (84.9 ± 26.5 vs 110.8 ± 48.2 ml/m2, P= 0.006) than patients with isolated PR. No significant difference was detected in RV ejection fraction and left ventricle volumes and function between the two groups. Multivariable linear regression analysis identified that transannular repair and peak pressure gradient of RVOT as independent predictors for RV volume. Patients with combined PR and RVOTO had higher (24.9 ± 5.2 vs 20.1 ± 6.3 ml/kg/min, P=0.07) peak oxygen uptake than patients with isolated PR. Peak RVOT gradient was the only independent predictor of exercise capacity in patients with combined PR and RVOTO.
Conclusions: Patients with combined PR and RVOTO had less dilated RV and better exercise capacity than those with isolated PR. An acceptable residual RVOTO is more advantageous in the long-term outcome of repaired TOF.
Author Disclosures: Q. Chen: None. S. Li: None. K. Yang: None. X. Pan: None. Z. Hua: None. H. Zhang: None. M. Lu: None. X. Sun: None. K. Ma: None. S. Zhang: None. L. Qi: None.
- © 2016 by American Heart Association, Inc.