Characterization of Favorable Right Ventricular Dimensions for Optimal Reverse Remodeling Following Pulmonary Valve Replacement.

We sought to couple current cardiac magnetic resonance (CMR) thresholds of right ventricular (RV) size and function with longitudinal trajectories of RV recovery, after pulmonary valve replacement (PVR). We aimed to identify optimal timing of PVR and couple CMR-based metrics with contemporaneous echocardiographic metrics. From June 2002 to January 2019, 174 patients with severe pulmonary regurgitation and peak RV outflow tract gradient <30 mm Hg underwent PVR at Cleveland Clinic. Mean age was 35 ± 16 years and 60 (34%) had concomitant tricuspid valve surgery. RV end diastolic area index (RVEDAi) and function metrics were measured by offline image review on preoperative and 794 postoperative echocardiograms. Contemporaneous RV end diastolic volume index (RVEDVi) was assessed on CMR and correlated to RVEDAi. Multiphase nonlinear mixed-effects models were used to analyze the longitudinal change in RV size and function after PVR. RVEDAi was correlated with RVEDVi (P < 0.0001, r = 0.59). RVEDAi decreased slowly over 10 years following PVR. An inflection point at 24 cm2/m2 was noted at 1 year post-PVR and was associated with failure of RV reverse remodeling and RVEDVi ≥150 mL/m2. Compared to patients with preoperative RVEDVi ≥150 mL/m2, patients with RVEDVi <150 mL/m2 had accelerated recovery of longitudinal trajectories of RV size and function metrics on echocardiograms. Reverse remodeling of RV following PVR is an ongoing process. Current accepted threshold values for PVR are associated with greatest RV recovery, suggesting that earlier PVR is warranted. Echocardiography can potentially be utilized in lieu of CMR for surveillance and interventional triage.