624 is TAVI a Useful Procedure in Paradoxical Low Flow-Low Gradient Aortic Stenosis? A Long-Term Mortality Study

Clinical outcomes of patients with paradoxical low-flow, low-gradient aortic stenosis (PLF-LG) undergoing valve replacement are controversial. PLF-LG is a combination of a small aortic valve area (AVA < 1cm²), a preserved left ventricular (LV) ejection fraction (LVEF≥50%), and a ‘paradoxical’ low mean gradient due to the presence of low LV stroke volume (≤35 mL/m²). The low flow state is explained by the presence of a high afterload and pronounced LV concentric remodeling, with impaired LV filling. Surgical aortic valve replacement has been associated with very positive outcomes in normal-flow high-gradient (NF-HG) AS, whereas poorer outcomes has been reported in patients with PLF-LG AS. The aim of this study is to determine the clinical outcomes in patients with PLF-LG AS undergoing transcatheter aortic valve implantation (TAVI) compare to NF-HG patients. A total of 624 patients (age 81 ± 7 years) with symptomatic severe AS and preserved LVEF who underwent TAVI, was enrolled and divided in 2 groups: group NF-HG included 554 patients (89%) and group PLF-LG including 70 patients (11%). At 1-year follow-up, death and clinical events were reported. TAVI was feasible in all patients. A significant reduction in mean aortic pressure gradient was observed after TAVI both in PLF-LG (baseline, 30 ± 6 mmHg; 1-year, 12 ± 4 mmHg; p < 0.001) and in NF-HG (baseline, 55 ± 12 mmHg; 1-year, 11 ± 4 mmHg; p < 0.001) together with an increase in AVA (PLF-LG: baseline, 0.73 ± 0.16 cm², 1-year: 1.82 ± 0.43 cm², p < 0.001; NF-HG: baseline, 0.66 ± 0.18 cm², 1-year: 1.84 ± 0.38cm², p < 0.001). Perioperative mortality at 30-days was similar in group NF-HG (17/554, 3%) and in group PLF-LG (2/70, 3%). Figure shows the survival curves up to 5 years follow-up according to the two groups. PLF-LG and HG-AS had similar survival rate throughout the long-term follow-up. Similarly, rehospitalization rate was not different in the two groups (PLF-LG: 12% vs NF-HG: 7%, p = 0.127). Differently from surgical series, TAVI in PLF-LG AS is a useful procedure showing similar mortality and rehospitalization rates compared to NF-HG AS patients. Abstract 624 Figure. Survival curve