Background: Recommended thresholds for pulmonary valve replacement (PVR) in asymptomatic patients after tetralogy of Fallot (TOF) repair are continually decreasing. We studied the natural history versus outcomes after PVR in various categories of indexed right ventricular end-diastolic volume (RVEDVi).
Hypothesis: We hypothesized that the benefit of PVR would not be outweighed by the risk at lower RVEDVi thresholds.
Methods: Acquisition of all repeated measure datapoints and cross-sectional review in 2579 patients (born 1924 - 2011), including 7553 echos, 2579 MRI scans and all interventional data. Analysis was via parametric competing risks techniques and time-related regressions adjusted for repeated measures.
Results: Survival was 95%, 81% and 73% at age 20, 40 and 60 years respectively. Freedom from PVR (N=516, mean age 25 years) was 87%, 66% and 45% at 20, 40 and 60 years after repair. Overall, survival after PVR was 98%, 95% and 87% at 1, 10 and 20 years. PVR-free survival in all 345 patients with MRI RVEDVi > 150 was 95% at 15 years. Comparative survival showed no survival advantage with PVR versus natural history for RVEDVi 150-160, 160-170, 170-180 (table); these categories had excellent PVR-free survival approaching 100% at 10 years. Patients with RVEDVi > 200 had late survival decrements with PVR or without. PVR resulted in a large and significant reduction in RVEDVi (mean 40 ml/m2, P<.0001), after which RVEDVi remained stable (P=.10). Patients with RVEDVi 150-160, 160-170 or 170-180 had similar reductions in RVEDVi after PVR to comparable levels (table). 35% of children transitioning to adult care had RVEDVi > 150 ml/m2.
Conclusions: Lowering the RVEDVi threshold for PVR does not appear to offer a clear survival advantage and offers small differences (if any) to RV geometry, risks potential procedure-related morbidity and would mean intervening on many teenagers with repaired TOF who could otherwise anticipate intervention in later life.