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Abstract 18317: Impact of Pulmonary Valve Replacement on Right Ventricular Myocardial Deformation in Repaired Tetralogy of Fallot


 Introduction:
 Pulmonary regurgitation is common following tetralogy of Fallot (TOF) repair and leads to progressive right ventricular (RV) dilatation and dysfunction. There is limited data on ventricular remodeling and adaption following surgical pulmonary valve replacement (PVR), especially beyond the short-term.
 
 
 Hypothesis:
 Our objective is to assess medium-term effects of PVR on right ventricular mechanics in patients with surgically repaired TOF.
 
 
 Methods:
 Speckle-tracking echocardiography was performed on pre-operative and post-operative echocardiograms in 50 patients with repaired TOF who underwent surgical PVR. RV global and segmental myocardial deformation parameters were assessed. Transthoracic studies 2.1±2.1 months pre-PVR, 2.23±0.61 months post-PVR (early follow-up) and 14.9±3.8 months post-PVR (medium-term follow-up) were analyzed.
 
 
 Results:
 The mean age at PVR was 12.6±3.3 years. Global RV longitudinal strain fell from -19.2%±2.7% to -16.8%±2.6% at early follow-up (p<0.001) but increased by late follow-up to -21.9%±3.1% (p<0.001). Basal segmental RV longitudinal strain showed a similar early reduction in strain followed by improvements late post-operatively (p<0.001). Mid-segmental RV longitudinal strain improved by late post-operative follow-up (p=0.002), whereas apical segmental RV strain increased in the early post-operative period (p=0.004). There was a weak inverse correlation between pre-operative RV indexed end-diastolic volumes and RV mean longitudinal strain (R2=0.383).
 
 
 Conclusion:
 Although an early reduction in RV longitudinal strain occurs following PVR, the volume unloading effects of PVR has a significant effect on late RV remodelling as reflected by improvements in global RV longitudinal, basal and mid segmental strain late post-PVR. The effects of reversed remodelling of the RV may have important clinical implications towards determining the optimal timing of PVR in this subset of patients.
 
 
 
