Impact of prolonged balloon inflation on valve expansion and early clinical outcomes following contemporary balloon-expandable transcatheter aortic valve implantation

BACKGROUND: Incomplete expansion of balloon-expandable (BE) transcatheter heart valves (THVs) after transcatheter aortic valve implantation (TAVI) may affect valve performance and durability. Routine THV post-dilatation (the "double-tap" technique) has been proposed to optimise device expansion; however, it may increase procedural complexity. AIMS: We sought to evaluate the impact of a prolonged balloon inflation implantation strategy on BE THV expansion, haemodynamic performance, and early clinical outcomes. METHODS: This single-centre study analysed consecutive TAVI patients treated for native tricuspid aortic stenosis with the SAPIEN 3 Ultra RESILIA THV using a prolonged balloon inflation strategy (8 seconds). Valve expansion was assessed by fluoroscopy at multiple frame levels and compared with three validated reference standards. Results were also descriptively compared with previously published data on the double-tap technique. Clinical and haemodynamic outcomes at 30 days were adjudicated according to Valve Academic Research Consortium 3 criteria. RESULTS: A total of 84 patients (mean age 78.8 years, 58% male, median Society of Thoracic Surgeons Predicted Risk of Mortality score 3.9%) were included. Prolonged inflation resulted in complete THV expansion at the inflow and outflow levels, with only mild underexpansion (98.5±1.3%) detected at the midframe level when manufacturer-defined nominal values were used as the reference. When compared with previously published data on the double-tap technique, expansion values for the 23, 26, and 29 mm valves were consistently similar or higher, whereas lower expansion was observed for the 20 mm size. Device success was achieved in all cases, with no stroke at 30 days. Permanent pacemaker implantation occurred in 6% of patients. Haemodynamic performance was favourable (mean gradient 9.2 [interquartile range 7.0-10.3] mmHg at 30 days), with no patients having moderate or severe paravalvular leak. CONCLUSIONS: Prolonged balloon inflation during BE THV deployment is associated with favourable valve expansion, haemodynamic results, and a favourable safety profile, consistent with values reported in double-tap series. If confirmed in larger studies, this strategy may represent a simple alternative to routine double-tap in selected patients.