Impact of aortic valve replacement in symptomatic low-risk patients with less than severe aortic stenosis

Objective: To evaluate whether transcatheter or surgical aortic valve replacement (TAVR or SAVR) affects clinical and haemodynamic outcomes in symptomatic patients with moderately-severe aortic stenosis (AS).

Methods: Echocardiographic evidence of severe AS for enrolment in the Evolut Low Risk trial was based on site-reported measurements. For this post hoc analysis, core laboratory measurements identified patients with symptomatic moderately-severe AS (1.0<aortic valve area (AVA)<1.5 cm², 3.0<peak velocity<4.0 m/s and 20≤mean gradient (MG) <40 mm Hg). Clinical outcomes were reported through 2 years.

Results: Moderately-severe AS was identified in 113 out of 1414 patients (8%). Baseline AVA was 1.1±0.1 cm², peak velocity 3.7±0.2 m/s, MG 32.7±4.8 mm Hg and aortic valve calcium volume 588 (364, 815) mm³. Valve haemodynamics improved following TAVR (AVA 2.5±0.7 cm², peak velocity 1.9±0.5 m/s and MG 8.4±4.8 mm Hg; p<0.001 for all) and SAVR (AVA 2.0±0.6 cm², peak velocity 2.1±0.4 m/s and MG 10.0±3.4 mm Hg; p<0.001 for all). At 24 months, the rates of death or disabling stroke were similar (TAVR 7.7% vs SAVR 6.5%; p=0.82). Kansas City Cardiomyopathy Questionnaire overall summary score assessing quality of life improved from baseline to 30 days after TAVR (67.0±20.6 to 89.3±13.4; p<0.001) and SAVR (67.5±19.6 to 78.3±22.3; p=0.001).

Conclusions: In symptomatic patients with moderately-severe AS, AVR appears to be beneficial. Determination of the clinical and haemodynamic profile of patients who can benefit from earlier isolated AVR needs further investigation in randomised clinical trials.