Association between valvuloarterial impedance after transcatheter aortic valve implantation and 2-year mortality in elderly patients with severe symptomatic aortic stenosis: the OCEAN-TAVI registry.

Pre-procedural valvuloarterial impedance (Zva) is considered as a useful predictor of mortality in patients diagnosed as having severe aortic stenosis (AS) who undergo transcatheter aortic valve implantation (TAVI). However, the prognostic significance of post-procedural Zva remains unclear. We aimed to evaluate the prognostic significance of Zva after TAVI. We retrospectively analyzed the clinical and echocardiographic data of 1004 consecutive elderly patients (median 84 years old, 27.5% men) who underwent TAVI for severe symptomatic AS. Zva was calculated after TAVI, and patients were divided into three groups based on tertile values: the high [> 3.33 (n = 335)], intermediate [2.49-3.33 (n = 334)], and low Zva groups [< 2.49 (n = 335)]. The estimated 2-year all-cause and cardiovascular mortalities using Kaplan-Meier analysis were 16.2% [95% confidence interval (CI) 11.8-20.4] and 5.9% (95% CI 3.2-8.6), respectively. There were no significant intergroup differences in each endpoint (long-rank p = 0.518 for all-cause mortality, p = 0.757 for cardiovascular mortality). Multivariable Cox regression analyzes with adjustments of patient characteristics and medications showed that the post-procedural Zva was not associated with the 2-year all-cause mortality [intermediate Zva group versus (vs.) low Zva group: adjusted hazard ratio (aHR) = 1.34, 95% CI 0.75-2.40, p = 0.316; high Zva group vs. low Zva group: aHR = 1.17, 95% CI 0.64-2.16, p = 0.613] and cardiovascular mortality (intermediate Zva group vs. low Zva group: aHR = 1.50, 95% CI 0.56-4.06, p = 0.421; high Zva group vs. low Zva group: aHR = 1.25, 95% CI 0.43-3.65, p = 0.682). Our results suggest that post-procedural Zva was not associated with 2-year all-cause or cardiovascular mortalities in patients with severe symptomatic AS who underwent TAVI.