Abstract 17148: Transcatheter Aortic Valve Replacement in Low-Risk Patients With Symptomatic Severe Aortic Stenosis: Two-Year Results From the LRT Trial

Objective: To evaluate clinical outcomes and transcatheter heart valve hemodynamics at 2 years after transcatheter aortic valve replacement (TAVR) in low-risk patients. Background: Early results from the Low Risk TAVR (LRT) trial demonstrated that TAVR is safe in patients with symptomatic severe aortic stenosis (AS) who are low surgical risk. Methods: The LRT trial was an investigator-initiated, prospective, multicenter study and was the first Food and Drug Administration-approved Investigational Device Exemption trial to evaluate feasibility of TAVR in low-risk patients. The primary endpoint was all-cause mortality at 30 days. Secondary endpoints included clinical outcomes and valve hemodynamics at 2 years. Results: The LRT trial enrolled 200 low-risk patients with symptomatic severe AS to undergo TAVR at 11 centers. Mean age was 73.6 years and 61.5% were men. At 30 days, there was zero mortality, zero disabling stroke, and a low permanent pacemaker implantation rate. At 2-year follow-up, mortality was 4.4%, stroke rate was 4.6%, and permanent pacemaker implantation rate was 9.0%. Four patients (2.3%) presented with endocarditis; two of these underwent surgical reintervention. Of the 14% of TAVR subjects who had evidence of subclinical leaflet thrombosis at 30 days, there was no impact on valve hemodynamics at 2 years or stroke rate (4.8%) versus 4.2% in patients who did not have leaflet thickening. Conclusions: TAVR in low-risk patients with symptomatic severe AS remains safe at 2 years. Subclinical leaflet thrombosis, observed in a minority of TAVR patients at 30 days, did not impact valve hemodynamics in the longer term.