Background: Moderate or worse paravalvular regurgitation (PVR) post-transcatheter aortic valve replacement (TAVR) is associated with increased mortality. The mechanisms by which this occurs are not fully understood.
Aims: To determine the mechanism by which PVR leads to worse outcomes.
Methods: 1,974 intermediate-risk patients who received TAVR in the PARTNER 2 trial and registries were grouped by PVR severity. Clinical and echocardiographic outcomes were compared.
Results: 1,176 (60%) patients had none/trace, 680 (34%) had mild, and 118 (6%) had ³moderate PVR. At 2 years, ³moderate PVR patients had increased risks of all-cause (HR 2.33 [1.41-3.85], P-value=0.001) and cardiovascular death (HR 3.30 [1.74-6.28], P-value<0.001), re-hospitalization (HR 2.68 [1.57-4.58], P-value<0.001), and re-intervention (HR 14.72 [3.13-69.32], P-value<0.001). ³Moderate PVR was associated with greater increases in left ventricular (LV) end diastolic and systolic dimensions and volumes, LV mass indices, and reductions in LV ejection fractions (LVEFs) from 30 days to 2 years. Mild PVR was not associated with worse outcomes. Adjusting for LV dimensions and LVEF from the 1-year echocardiogram, patients with ³moderate PVR still had an increased risk of all-cause death or re-hospitalization at 2 years (HR 2.84 [1.25-5.78], P-value=0.009).
Conclusions: ³Moderate PVR, but not mild PVR, is associated with an increased risk of all-cause and cardiovascular death, re-hospitalization, and re-intervention at 2 years. ³Moderate PVR is also associated with adverse LV remodeling, which partially mediates how ³moderate PVR leads to worse outcomes. These results provide dual insights on the deleterious impact of ³moderate PVR and the contributing mechanisms of poor clinical outcomes.