P1788The outcome of TAVI in patients with small annulus and the comparison between intra-annular and supra-annular devices in small anulus: From the analysis of the Japanese nationwide registry
Authors: Meguro K , Hashimoto T , Yanagisawa T , Kitamura T , Ako J 
Published: October 2019

Abstract

Background
Transcatheter aortic valve implantation (TAVI) has been widely accepted strategy of the treatment for aortic stenosis in patients at intermediate to high or prohibitive surgical risk. The Asian people are of smaller body size compared to Western people. As the result, Asian people have smaller aortic annulus size, which accommodate only smaller transcatheter heart valves (THVs), however, the details and consequences of small aortic annulus size in TAVI is uncertain.

Purpose
The purposes of this study were to clarify the short-term outcomes of TAVI in patients with small annulus and the differences of intra-annular and supra-annular THVs in small annulus using Japanese national TAVI registry.

Methods
Multi-detector computed tomography (MDCT) was performed before TAVI and the annulus area was registered. We compared the 30-day clinical outcomes between patients with and without small annulus (annulus area 3.14cm2). Further investigation to compare intra-annular and supra-annular THVs in patients with small annulus was conducted.

Results
The total of 5,870 patients (103 sites in Japan) who underwent TAVI between August 2013 to December 2017 were enrolled in this study. Out of 5,870 patients, 647 had small annulus.
Thirty-day mortality, new pacemaker implantation and stroke rate were comparable between patients with and without small annulus. Echocardiography within 30 days after TAVI revealed that patients with small annulus had significantly smaller indexed effective orifice area (iEOA, 1.10.cm2/m2 [0.92–1.35] vs. 1.16 cm2/m2 [0.96–1.39], p<0.001), higher mean pressure gradient (10.0 mmHg [6.9–14.2] vs. 8.5 mmHg [6.0–11.5], p<0.001) and lower frequency of paravalvular leakage moderate (17.3% vs. 24.4%, p<0.001). Patient-prosthesis mismatch (PPM) were more frequent in patients with small annulus (p=0.002). Logistic regression analysis revealed that small annulus (OR: 1.82; 95% CI: 1.45–2.30, p<0.001), female gender (OR: 0.54; 95% CI: 0.42–0.70, p<0.001), weight (OR: 1.03; 95% CI: 1.02–1.04, p<0.001), height (OR: 1.04; 95% CI: 1.02–1.05, p<0.001), hyperlipidemia (OR: 1.25; 95% CI: 1.07–1.47, p=0.006), femoral access (OR: 0.80; 95% CI: 0.66–0.97, p=0.026) were significantly associated with the PPM after TAVI.
The use of SAPIEN 3 20mm THV in patients with small annulus was associated with the smaller iEOA (0.94 cm2/m2 [0.78–1.06] vs. 1.07 cm2/m2 [0.84–1.24], p=0.001) and higher mean pressure gradient (14.0 mmHg [10.0–18.5] vs. 11.0 [7.0–14.0], p<0.001) compared to the usage of Evolut R 23 mm THV. The rate of paravalvular leakage more than moderate was similar in both THVs (14.4% vs. 16.5%, p=0.69).

Conclusions
Small annulus did not affect clinical 30-day outcomes, however, small annulus was associated with smaller iEOA and higher mean pressure gradient. Supra-annular device might contribute the better hemodynamical improvement in patients with small annulus without increase of paravalvular leakage.

Acknowledgement/Funding
None