Minimalist transcatheter aortic valve replacement misses paravalvular regurgitation: Incidence and echocardiographic distribution of missed paravalvular regurgitation

Background: Paravalvular regurgitation (PVR) may be missed intraoperatively with transthoracic echocardiography (TTE) guided minimalist TAVR. We sought to determine the incidence and echocardiographic distribution of PVR missed on intra-op TTE, but detected on predischarge TTE. Methods: From July 2015 to 2020, 475 patients with symptomatic severe native aortic stenosis underwent TTE-guided minimalist TAVR. Missed PVR was defined as predischarge PVR that was ≥1 grade higher than the corresponding intra-op PVR severity. PVR was classified as anterior or posterior on the four standard TTE views; parasternal short-axis (PSAX), parasternal long-axis (PLAX), apical 3-chamber (A3C), and 5-chamber (A5C). Location-specific risk of missed PVR was then determined. Results: Mild or greater PVR was seen in 55 (11.5%) cases intra-op and 91 (19.1%) at predischarge, with no severe PVR. Among the 91 patients with ≥mild predischarge PVR, missed PVR was present in 42 (46.2%). Compared to the corresponding anterior jets, missed PVR rate was significantly higher for posterior jets in PLAX (62.5% vs. 25.0%, p = 0.005), A5C (56.9% vs. 25.0%, p = 0.009), PSAX (66.7% vs. 24.3%, 0.001), but not A3C (58.5% vs. 40.0%, p = 0.28). Conclusions: Intraoperative TTE-guided minimalist TAVR either misses nearly half of ≥mild PVR or underestimates PVR by ≥1 grade when compared to predischarge TTE. Posterior PVR jets are more likely to be missed. Transesophageal echo guidance may help minimize missing PVR. Further studies are warranted.