Simple Index for Identifying Patients at Increased Risk of Suboptimal Forward-Flow Hemodynamics After Transcatheter...

Among patients treated for severe aortic stenosis, a small aortic annulus could have a different impact on outcomes according to body size. We aimed to compare forward-flow hemodynamics and clinical outcomes after transcatheter aortic valve replacement in patients with small annuli according to aortic annular area (AAA) index, defined as computed tomography-derived AAA divided by body surface area.

The TAVI-SMALL 2 (International Multicenter Registry to Evaluate the Performance of Self-Expandable Valves in Small Aortic Annuli 2) observational, retrospective, international cohort study enrolled patients with severe aortic stenosis and small annuli in 16 high-volume centers between 2011 and 2020. Analyses comparing patients with low (ie, ≤2 cm²/m²) and high AAA index (ie, >2 cm²/m²) were conducted adopting propensity score methodology. Primary end points were predischarge device forward-flow composite (including mean aortic gradient ≥20 mm Hg or severe prosthesis-patient mismatch), and clinical efficacy composite (including all-cause death, transient ischemic attack/stroke, or hospitalization for heart failure) at 1-year follow-up.

A total of 1256 patients were included in the analysis. In the 1:1 propensity score-matched population (n=688), the primary predischarge forward-flow composite end point occurred in 48 patients (7.5%) overall and was more common in low versus high AAA index (9.7% versus 5.3%, P=0.034). The primary composite clinical efficacy end point occurred in 95 patients (18.1%), and no difference between groups was observed at 1-year follow-up (11.5% [95% CI, 7.8%-16.8%] versus 14.4% [95% CI, 10.4%-19.9%], hazard ratio, 0.89 [95% CI, 0.59-1.33]; P_log-rank=0.842).

Among patients with small aortic annuli undergoing transcatheter aortic valve replacement, the novel AAA index further identifies patients at increased risk of predischarge suboptimal forward-flow hemodynamics. No difference in clinical efficacy at 1-year follow-up was observed according to the AAA index.