Transcatheter aortic valve replacement (TAVR) provides comparable stroke and mortality rates out to 1 year in low-risk patients with bicuspid and tricuspid aortic stenosis, registry data suggest.
Recent pivotal randomized trials expanded the indication for TAVR to low-surgical-risk patients with aortic stenosis, but excluded those with bicuspid anatomy. TAVR registry data also have been limited to smaller or older, high-risk patients.
The current study focused on 3168 pairs of propensity-matched patients with bicuspid and tricuspid aortic stenosis, drawn from 37,660 patients at low surgical risk (STS score, <3%) who underwent TAVR with a contemporary balloon-expandable valve between June 2015 and October 2020 in the Society of Thoracic Surgeons/American College of Cardiology (STS/ACC) TVT Registry. Their mean age was 69 years and mean STS score was 1.7%.
Procedural complications were uncommon, at 0.5% or less, and did not differ between the bicuspid and tricuspid groups.
There was no significant difference in the primary outcomes of death and stroke at 30 days and 1 year between the bicuspid and tricuspid cohorts, reported lead author Raj R. Makkar, Cedars Sinai Medical Center, Los Angeles.
30-day death: 0.9% vs 0.8% (hazard ratio [HR], 1.18; P = .55)
30-day stroke: 1.4% vs 1.2% (HR, 1.14; P = .55)
1-year death: 4.6% vs 6.6% (HR, 0.75; P = .06)
1-year stroke: 2.0% vs 2.1% (HR, 1.03; P = .89)
There were also no significant differences at either time point in valve hemodynamics or moderate/severe paravalvular leaks. Both groups also had similar and significant gains in functional status and quality-of-life measures.
Nevertheless, Makkar and colleagues say the findings should be interpreted as "exploratory" and that further research is needed to direct the optimal approach in younger patients with bicuspid aortic stenosis, who are likely to require multiple valve procedures over their lifetime because of limited bioprosthetic valve durability.
"Because of the potential for selection bias and absence of a control group treated surgically for bicuspid stenosis, randomized trials are needed to adequately assess the efficacy and safety of transcatheter aortic valve replacement for bicuspid aortic stenosis in patients at low surgical risk," they conclude.
Although TAVR is clearly possible in these patients, "it is unclear whether TAVR is an appropriate option due to clinical concerns, such as valve durability and procedural risk, and anatomic challenges, such as asymmetrical valve anatomy, annular calcification, and associated aortic disease," say Catherine M. Otto, MD, University of Washington School of Medicine, Seattle, and David E. Newby, MD, University of Edinburgh, United Kingdom.
They point out in an accompanying editorial that patients with bicuspid aortic valve disease develop severe aortic stenosis about 10 years earlier than those with a tricuspid valve, and those study participants were 7.2 years younger than their tricuspid counterparts in the study.
"Therefore, questions regarding longevity of transcatheter bioprosthetic valves becomes increasing important, with this study reporting only 1-year outcomes and robust data extending to only about 5 years available in the published literature," Otto and Newby say. "Younger patients also may be less willing to accept the need for permanent pacemaker implantation (as occurred in the 6.2% of BAV patients in the study by Makkar et al) given the associated long-term complications of such devices."
The editorialists also observe that US guidelines continue to recommend surgical aortic valve replacement over TAVR in patients with severe aortic stenosis younger than 65 years.
Makkar reported receiving research grants from Edwards Lifesciences, Medtronic, Abbott, and Boston Scientific; and receiving personal fees from Edwards Lifesciences for travel. Otto and Newby reported no relevant financial relationships.
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Cite this: TVT Registry Low-risk Bicuspid TAVR 1-Year Results Hit Print - Medscape - Sep 24, 2021.