Bicuspid valve CT Registry of balloon expandable TAVR: BETTER TAVR Registry

Abstract Objectives We evaluated determinants of stent geometry in bicuspid valves treated with balloon expandable TAVR. Background The anatomic substrate of bicuspid valves may lead to suboptimal TAVR stent expansion and geometry. Methods A multicentre observational registry of patients who underwent post TAVR CT to determine stent area (vs nominal valve area) and stent ellipticity (maximum diameter/minimum diameter). Predictors of relative stent expansion (minimum area/average of inflow + outflow area) and stent ellipticity were evaluated in a multivariable regression model including valve calcium volume, presence of raphe calcium, sinus diameters indexed for area derived annular diameter, and performance of pre-dilation and post-dilation. Results The registry enrolled 101 patients from 4 centres. Minimum stent area (vs nominal area) was 88.1% and maximum ellipticity was 1.10 with both observed near the midframe of the valve in all cases. Relative stent expansion ≥90% was observed in 64/101 patients. The only significant predictor of relative stent expansion ≥90% was performance of post-dilation (p<0.01). Relative stent expansion ≥90% was seen in 86% of patients with post dilation compared to 57% of without (p<0.001). The stent ellipticity ≥ 1.1 was observed in 47/101 patients. The significant predictors of stent ellipticity ≥1.1 was the presence of raphe calcification (p=0.02) and intercommisural diameter at 4 mm above the annular plane (p=0.004). Conclusion Relative stent expansion ≥90% was associated with the performance of post-dilation and stent ellipticity was associated with the presence of calcified raphe and sinus dimensions (Intercommisural diameter at 4 mm above the annular plane). Further studies to determine optimal deployment strategies in bicuspid valves are needed. Abstract Figure Graphical abstract Predictors of stent expansion and ellipticity from a multicenter registry of patients with bicuspid anatomy undergoing TAVR with balloon expandable valves.