Strain echocardiographic assessment of ventricular function after percutaneous pulmonary valve implantation

Percutaneous pulmonary valve implantation (PPVI) is an emerging therapy for pulmonary valve dysfunction. Minimal data on the midterm effects of PPVI on ventricular function exist. We describe the effects of PPVI on right and left ventricular (RV, LV) function with speckle tracking echocardiography.

Patients who met the inclusion criteria of the Food and Drug Administration Phase 1 Feasibility Clinical Trial PPVI were identified. Patients were studied with echocardiograms at baseline, post-PPVI (day of discharge), 3 months, and at 6 months. Patients were studied by cardiac magnetic resonance at baseline and at 6 months. Longitudinal strain was measured at the basal, mid, and apical portions of the RV, interventricular septum (IVS), and LV. Global RV and LV strain and strain rates were recorded. Paired t-tests were used for analysis.

Ten patients were analyzed: nine patients were a variant of tetralogy of Fallot and one patient had complex LV outflow obstruction requiring a Ross and RV-pulmonary atresia conduit. Mean age was 24.4 ± 7.6 years. Indication for PPVI was pulmonary regurgitation in six patients, stenosis in two patients, and stenosis/regurgitation in two patients. After PPVI, both RV systolic pressure and RV to pulmonary artery pressure gradient significantly decreased. Cardiac magnetic resonance RV end-diastolic volume significantly decreased. IVS-mid, IVS-apical, and LV-global strain significantly increased and RV-basal decreased immediately after PPVI. Global RV a' strain rate significantly increased immediately after PPVI. However, RV, IVS, and LV strain/strain rate values between baseline and the 6 month echocardiographic study were either similar or significantly decreased.

Despite improvement in RV hemodynamics, there was a decrease or no improvement in RV and LV function as measured by strain echocardiographic values at midterm follow-up. Larger studies with longer follow-up are needed to determine if these results remain consistent.