P0386 - Does Transcatheter Pulmonary Valve Replacement Affect Left Ventricle Systolic Function: A 2 Dimensional Speckle Tracking Study?

Background: In patients with right ventricle (RV) to pulmonary artery (PA) conduit, pulmonary regurgitation, and stenosis lead to RV dilatation and dysfunction. Transcatheter pulmonary valve replacement (tPVR) is an alternative to surgical replacement of PV in patients with significant RV dilatation, with studies showing an improvement of RV volume and function after the procedure. However, data are lacking on the effect of tPVR on the left ventricle (LV) systolic function. Our goal was to assess LV function using 2D echocardiographic speckle tracking imaging (STI) in patients following PVR.

Methods: This was a single-center retrospective cross-sectional study of patients who had undergone tPVR. Patients who had LV systolic dysfunction prior to tPVR, mechanical valve, or LV outflow obstruction were excluded. The echocardiograms were read at 3-time points: before, one day, and 1-3 months after tPVR. Data were analyzed offline by a trained observer using vendor-independent software (TomTec Imaging). Global longitudinal strain for endocardium (GLSendo) and myocardium (GLSmyo) were calculated from the apical 4 chamber view. Statistical analysis included repeated measures ANOVA to compare echo parameters over 3-time points. P-value < 0.05 was considered significant.

Results: Our cohort (n=26) included 13 (50%) males with a mean (SD) age of 21.4 (10.6) years at the time of tPVR. Cardiac diagnoses included Tetrology of Fallot 16 (62%), Ross procedure 4 (15%), and Truncus arteriosus 6 (23%). The primary indications for tPVR were stenosis in 16 patients, free regurgitation in 6, and mixed in 4 patients. There was a significant improvement in the GLSendo and GLSmyo from pre to post tPVR (Table). However, there were no differences in LV end-diastolic or systolic volumes before and after PVR.

Conclusions: There was a significant improvement in LV systolic function as assessed by STI following transcatheter PVR in patients with RV to PA conduit. There was no change in LV volume after PVR, suggesting that the improvement in function could be related to better inter-ventricular interaction. Further studies using cardiac MRI volume are needed to understand the mechanisms of improvement of LV systolic function following tPVR.