Outcomes after transcatheter aortic valve replacement in patients with low versus high gradient severe aortic stenosis in the setting of preserved left ventricular ejection fraction.

Abstract

Transcatheter aortic valve replacement (TAVR) for low gradient (LG) severe aortic stenosis (AS) with preserved left ventricular ejection fraction (LVEF) remains an area of clinical uncertainty. Retrospective review identified 422 patients who underwent TAVR between September 4, 2014 and July 1, 2016. Procedural indication other than severe AS (n = 22) or LVEF <50% (n = 98) were excluded. Outcomes were defined by valve academic research consortium two criteria when applicable and compared between LG (peak velocity <4.0 m/s and mean gradient <40 mmHg; n = 73) and high gradient (HG) (n = 229) groups. The LG group was further categorized as low stroke volume index (SVI) (n = 41) or normal SVI (n = 32). Median follow-up was 747 days [interquartile range 220-1013]. Baseline thirty-day mortality risk (LG 6.2% [3.8-8.1] vs HG 5.7% [4.1-7.4], P = 0.43) did not differ between groups. Short-term outcomes, including procedural success rate (86.1% vs 88.8%, P = 0.53), peri-procedural complications (intra-procedural heart block: 6.8% vs 7.9%, P = 0.99; permanent pacemaker placement: 11.0% vs 13.6%, P = 0.69; moderate paravalvular regurgitation: 2.7% vs 1.3%, P = 0.60), and all-cause in-hospital mortality (2.7% vs 0.9%, P = 0.25) did not differ between LG and HG groups. On long-term follow-up, all-cause mortality also did not differ between LG and HG groups (6.8% vs 10.0%, plog-rank = 0.33) or between the LG low SVI (9.8%), LG normal SVI (3.1%), and HG (10.0%) groups (plog-rank = 0.39). Patients with preserved LVEF undergoing TAVR for severe AS with LG, including LG with low SVI, have no significant difference in adverse outcomes when compared to patients with HG.