BACKGROUND: Transcatheter aortic valve replacement (TAVR) technology and techniques have continuously improved, but data on their impact in low-flow, low-gradient aortic stenosis (LFLG-AS) remain limited. In particular, scarce data exist comparing the results of TAVR with new-generation devices vs early-generation devices in these patients. This study evaluated the temporal trends in TAVR practices among LFLG-AS patients. METHODS: This multicentre registry included 424 LFLG-AS patients undergoing TAVR from 2007 to 2023, stratified by device generation: new-generation devices (n = 193) and early-generation devices (n = 231). All-cause mortality or heart failure hospitalization (HFH) at 1-year follow-up was the primary end point. RESULTS: The median Society of Thoracic Surgeons score was lower in the new-generation group (5.3% [interquartile range [IQR] 3.4%-8.2%] vs 7.4% [IQR 5.0%-12.1%]
P <
0.002), whereas left ventricular ejection fractions (LVEFs) were similar (new: 31.2 ± 8.3%
early: 30.0 ± 8.8%
P = 0.16). New-generation devices were associated with a significant reduction in moderate-to-severe paravalvular leak after TAVR (2.6% vs 9.1%
P = 0.005), although 30-day mortality was similar (new: 1.6%
early: 3.9%
P = 0.15). At 1 year, new-generation devices were associated with a greater LVEF improvement (43.8 ± 12.5% vs 39.8 ± 11.5%
P = 0.003), but without a significant reduction in all-cause mortality or HFH (new: 23.8%
early: 28.1%
P = 0.32). Chronic kidney disease and low hemoglobin independently predicted worse outcomes (P <
0.05). CONCLUSIONS: Despite procedural improvements with new-generation TAVR devices, clinical outcomes in LFLG-AS patients remain suboptimal. LVEF significantly improved after TAVR with new-generation devices but failed to translate into improved clinical outcomes. These findings suggest that TAVR alone may not suffice in this population and underscore the need for a comprehensive therapeutic approach that integrates TAVR with optimized medical management and cardiac rehabilitation.