Post-dilatation using the balloon-expandable valve delivery balloon with same volume (double-tap) to optimise transcatheter aortic valve expansion

Background Transcatheter heart valve (THV) underexpansion is associated with hemodynamic valve deterioration. Double-inflation of balloon-expandable valves using the delivery balloon with unchanged volume (double-tap) may improve THV expansion, whilst minimising the risk of complications. Aim To evaluate the efficacy of double-tap after transcatheter aortic valve replacement (TAVR) with SAPIEN-3 Ultra RESILIA (S3UR) valves. Methods This observational study included consecutive patients who underwent TAVR for severe native aortic stenosis and had same-volume double-tap. Patients were included from a single high-volume centre from November 2024 to September 2025. We excluded patients with prior TAVR or surgical aortic valve replacement, severe left ventricular outflow tract or annular calcium, or aortic regurgitation as the indication for TAVR. THV expansion and deformation were assessed fluoroscopically before and after double-tap (after appropriate calibration). Expansion (%) = ((Pi x [THV diameter divided by 2]2) divided by nominal THV area) x 100. Deformation index = (area at THV inflow + outflow) divided by (2 x area at narrowest). Thirty-day clinical outcomes were reported. Results Of 113 patients who underwent TAVR with same-volume double-tap (mean age: 79.3±7.3 years, 26.5% female, 13.3% bicuspid anatomy), the median THV expansion before double-tap, at the inflow, mid-portion and outflow was 88.6% (IQR: 86.4-90.4%), 80.1% (IQR: 77.3-82.3%) and 90.1% (IQR: 88.4-90.0%) respectively, and after double-tap increased to 96.4% (IQR: 94.6-98.4%), 90.8% (IQR: 88.6-92.0%) and 97.6% (IQR: 96.2-99.0%) (all P<0.001). The largest increase in expansion following double-tap occurred in the THV mid-portion (median: 10.6% [IQR: 9.9–11.6%]) (Figures). Multivariable predictors of the extent of minimum expansion improvement following double-tap were bicuspid anatomy (median increase with bicuspid vs. tricuspid: 11.7% [IQR: 11.2-12.8%] vs. 10.6% [9.7-11.4%], coefficient 0.27 [95% confidence interval (CI): 0.08-0.45] P=0.005) and aortic valve calcium volume >median (385mm3) (median increase with calcium volume >385mm3 vs. </= 385mm3: 11.1% [IQR: 10.0-12.1%] vs 10.4% [IQR: 9.8-11.2%], coefficient 0.19 [95% CI: 0.00-0.38] P=0.046). Even though pre-dilatation was undertaken in 60% of patients, this did not mitigate the benefit of double tap on THV expansion (median increase in minimum expansion with vs. without pre-dilatation: 11.1% [IQR: 10.0-12.1%] vs. 10.3% [IQR: 9.4-11.0%], coefficient 0.11 [95% CI: -0.09 to 0.30] P=0.278). The median THV deformation index decreased from 1.05 (IQR: 1.04-1.07) to 1.03 (IQR: 1.02-1.04) after double-tap (P<0.001). Thirty-day mortality rate was 0.9%. Conclusion Routine double-tap post-dilatation of balloon-expandable valves appears safe, and improves THV expansion and frame deformation. Bicuspid anatomy and aortic valve calcium burden were associated with the extent of expansion improvement after double-tap.