Patients with symptomatic bicuspid aortic stenosis (AS) with low surgical risk who underwent TAVR continued to show excellent clinical outcomes and valve hemodynamics at one year. The rate of subclinical leaflet thrombosis in this subset of 72 patients was similar to patients with trileaflet aortic valve morphology treated with TAVR.
Bicuspid patients were a 72 patient sub-study excluded from the Low Risk TAVR (LRT) study and were recruited between August 2016 and February 2020. The LRT bicuspid cohort objective was to assess the feasibility of TAVR with commercially available valves in patients with low risk (STS PROM <3) bicuspid patients with symptomatic, severe AS. Outcomes at 30-days were presented back in February 2020, showing zero mortality and zero disabling strokes at 30 days. Results of one-year follow-up from this sub-study were presented recently as part of CRT 2021 Virtual Conference.
Compared to their trileaflet counterparts, the bicuspid cohort was younger (mean age = 68.1 +/- 7.7 years compared to 73.6 +/- 6.1 years) with a similar constellation of comorbid conditions. One year outcome data were evaluable for 67 bicuspid patients; 3 were lost to follow up,1 withdrew from the study and 1 had not reached one year. The evaluable bicuspid TAVR cohort had rates of mortality, stroke, acute myocardial infarction and new-onset atrial fibrillation (AF) at one year that were similar to trileaflet patients treated in the main LRT study. One bicuspid patient (1.5%) died suddenly at 291 days, 3 (4.5%) sustained non-disabling strokes and 2 (3%) developed new AF. Pacemakers were required in 9/67 (13.4%) patients available for evaluation at 1 year.
The majority of treated patients with bicuspid AS were classified as Sievers Type 1 (82.5%) while 14.2% of patients were classified as Sievers Type 0 (no raphe). All patients were treated via transfemoral approach, and less than one-fifth of the bicuspid TAVR cohort were treated with a 23 mm valve or smaller, compared to the surgical bicuspid cohort, in which the majority were treated with a 23 mm or smaller; 48/72 (66.7%) patients were treated with balloon-expandable valves and the remainder were self-expanding.
This important study adds to evolving evidence that TAVR may have a role in selected patients with bicuspid aortic valve morphology. This is one of the few cardiovascular studies with a majority of female patients enrolled (54.2%) despite bicuspid aortic valve disorders being 2 to 3 times more prevalent in males. This, and the somewhat advanced age of enrolled patients compared with the overall population of people with symptomatic bicuspid aortic stenosis, indicates this is a highly select group of bicuspid aortic stenosis patients.