Five-Year Clinical and Echocardiographic Outcomes from the Nordic Aortic Valve Intervention (NOTION) Randomized Clinical Trial in Lower Surgical Risk Patients

BACKGROUND: The Nordic Aortic Valve Intervention (NOTION) was designed to compare transcatheter aortic valve replacement (TAVR) to surgical aortic valve replacement (SAVR) in patients 70 years or older with isolated severe aortic valve stenosis. Clinical and echocardiographic outcomes are presented after 5 years.

METHODS: Patients were enrolled at three Nordic centers and randomized 1:1 to TAVR using the self-expanding CoreValve prosthesis (n=145) or SAVR using any stented bio-prostheses (n=135). The primary composite outcome was the rate of all-cause mortality, stroke, or myocardial infarction at 1 year defined according to Valve Academic Research Consortium-2 criteria.

RESULTS: Baseline characteristics were similar. The mean age was 79.1±4.8 years and mean STS-PROM score was 3.0%±1.7%. After 5 years, there were no differences between TAVR and SAVR in the composite outcome (Kaplan-Meier estimates 38.0% vs. 36.3%, log-rank test p=0.86) or any of its components. TAVR patients had larger prosthetic valve area (1.7 cm2 vs. 1.2 cm2, p<0.001) with a lower mean transprosthetic gradient (8.2 mm Hg vs. 13.7 mm Hg, p<0.001), both unchanged over time. More TAVR patients had moderate/severe total aortic regurgitation (8.2% vs. 0.0%, p<0.001) and a new pacemaker (43.7% vs. 8.7%, p<0.001). Four patients had prosthetic re-intervention and no difference was found for functional outcomes.

CONCLUSIONS: These are currently the longest follow-up data comparing TAVR and SAVR in lower risk patients, demonstrating no statistical difference for major clinical outcomes 5 years after TAVR with a self-expanding prosthesis compared to SAVR. Higher rates of prosthetic regurgitation and pacemaker implantation were seen after TAVR.

CLINICAL TRIAL REGISTRATION: URL: http://www.ClinicalTrials.gov. Unique identifier: NCT01057173.