Long-Term Outcomes After Transcatheter Aortic Valve Replacement: Not All Bicuspid Aortic Valves Are the Same

As transcatheter aortic valve replacement (TAVR) expands into younger, lower-risk populations, the question of how valve anatomy influences long-term outcomes becomes increasingly important—especially in patients with bicuspid aortic valves.

A recently published study in JACC: Cardiovascular Interventions provides new insight into this issue. This international, multicenter retrospective cohort study included 2,553 patients who underwent TAVR before October 2018 at three high-volume heart centers in China, Germany, and Denmark. With follow-up extending to 2023, this is among the most comprehensive evaluations to date of how aortic valve morphology influences long-term clinical outcomes following TAVR.

Key Findings:

Patients were classified according to anatomical subtypes:

• Type 0 bicuspid aortic valve (n = 134)
• Type 1 bicuspid aortic valve (n = 305)
• Tricuspid aortic valve (n = 2,114)

The primary outcome was all-cause mortality at five years. The results revealed significant differences in long-term survival based on valve anatomy:

• The five-year all-cause mortality rate was 11.0 percent in the type 0 bicuspid group, 34.5 percent in the type 1 bicuspid group, and 45.5 percent in the tricuspid group.
• Cardiovascular mortality was similarly lower in the type 0 bicuspid group (4.3 percent) compared with type 1 bicuspid (18.1 percent) and tricuspid (27.9 percent) patients.
• In fully adjusted Cox regression models, the risk of all-cause death was more than three times higher in tricuspid valve patients compared with those with type 0 bicuspid valves (adjusted hazard ratio 3.02). Type 1 bicuspid patients also had a higher risk (adjusted hazard ratio 2.38).

Device Type Matters—But Only in Certain Anatomies:

Among patients with bicuspid aortic valves, the type of transcatheter heart valve used was strongly associated with long-term outcomes:

• Patients treated with self-expanding valves had significantly lower all-cause mortality (23.6 percent) compared with those treated with balloon-expandable valves (41.7 percent).
• Cardiovascular mortality was similarly lower in the self-expanding valve group (11.0 percent versus 24.4 percent).
• No significant difference in long-term mortality by device type was observed among patients with tricuspid valves.

These findings suggest a potential interaction between anatomical subtype and valve platform selection. Notably, the hemodynamic advantages of self-expanding valves—particularly in terms of mean gradient reduction over time—may contribute to this survival benefit in bicuspid anatomy.

Anatomical Subtype as a Predictor of Outcome:

What explains the superior outcomes observed in patients with type 0 bicuspid valves?

Several hypotheses are proposed. Type 0 bicuspid aortic valve is considered a congenital malformation, with less contribution from systemic degenerative or inflammatory processes. These patients were younger, had fewer comorbid conditions, and experienced the lowest rates of permanent pacemaker implantation post-TAVR.

By contrast, type 1 bicuspid aortic valves—defined by fusion at the raphe—may combine features of congenital and degenerative disease. The hybrid pathology may result in ongoing disease progression even after mechanical correction of the stenosis, which may partially account for the intermediate outcomes seen in this group.

Tricuspid aortic stenosis, predominantly a degenerative condition, was associated with the highest mortality at five years.

Sensitivity and Subgroup Analyses:

The investigators performed extensive sensitivity analyses, including:

• Landmark analysis at 30 days
• Complete-case five-year follow-up
• Geographic subgroup analysis
• Subgroup comparisons across procedural characteristics

All analyses confirmed the primary findings: patients with type 0 bicuspid valves had the most favorable long-term outcomes, followed by type 1 bicuspid, and then tricuspid valve patients.

Implications for Practice:

This study adds important context to the growing literature on TAVR in bicuspid aortic valve disease:

1. Not all bicuspid valve anatomies are the same. Distinguishing between type 0 and type 1 bicuspid valves is not academic—it has long-term prognostic implications.
2. Type 0 bicuspid patients may be particularly well suited for TAVR using self-expanding valves, based on the combination of favorable anatomy and improved long-term hemodynamics.
3. As TAVR use expands, accurate anatomical characterization and valve-device matching will be critical to optimizing outcomes.

Next Steps:

Randomized controlled trials are needed to confirm these observational findings and to guide evidence-based selection of valve platforms based on bicuspid subtype. Moreover, the high proportion of type 0 bicuspid patients in some Asian populations provides an opportunity to conduct focused clinical trials in a population enriched for this anatomy.

Future research should also explore genetic and molecular contributors to differential outcomes among bicuspid subtypes, particularly the role of structural valve degeneration, systemic inflammation, and myocardial remodeling.

Conclusion:

In long-term follow-up, patients with type 0 bicuspid valves had significantly better survival after transcatheter aortic valve replacement than those with type 1 bicuspid or tricuspid valves. The results highlight the importance of anatomical classification and support a precision approach to device selection in patients with bicuspid aortic stenosis.

As TAVR moves into younger and lower-risk populations, these insights will be critical for improving procedural durability and long-term patient outcomes.