TAVI for low-flow, low-gradient severe aortic stenosis with preserved or reduced ejection fraction: a subgroup analysis from the German Aortic Valve Registry (GARY)

Aims: The study analyses the outcome of patients undergoing transcatheter aortic valve implantation (TAVI) for different subtypes of severe aortic stenosis (AS) based on data from the GARY registry. Methods and results: Low-EF, low-gradient (LEF-LGAS: EF <= 40%, MPG <40 mmHg), paradoxical low-gradient (PLF-LGAS: EF >= 50%, MPG <40 mmHg) and high-gradient AS (HGAS: MPG >= 40 mmHg) were observed in 11.7% (n=359), 20.8% (n=640) and 60.6% (n=1,864) of the study population, respectively. EuroSCORE I(36.7 +/- 20.9 vs. 22.6 +/- 15.7 vs. 24.3 +/- 17.4; p<0.001) differed significantly among subgroups. In-hospital and one-year mortality were higher in patients with LEF-LGAS compared to HGAS (in-hospital: 7.8% vs. 4.9%; p=0.029; one-year: 32.3% vs. 19.8%; p=0.001). In contrast, mortality in patients with PLF-LGAS was comparable to patients with HGAS (in-hospital: PLF-LGAS: 5.3%; p=0.67; one-year: 22.3%; p=0.192). The rate of TAVI-associated complications was not significantly different among groups. However, postoperative low cardiac output occurred significantly more frequently in patients with LEF-LGAS. Conclusions: Severe AS with a reduced transaortic flow and gradient is a common finding and is present in >30% of patients undergoing TAVI. Patients with low flow and impaired LV function have a significantly higher mortality within the first year after TAVI. In contrast, the outcome of patients with low flow and preserved EF is comparable to those with a high transvalvular aortic gradient.