Risk of Mortality, Stroke Similar After TAVR for Aortic Stenosis

Raj R. Makkar, MD

A recent study evaluated the outcomes of transcatheter aortic valve replacement (TAVR) with contemporary balloon-expandable transcatheter heart valves in bicuspid aortic stenosis versus tricuspid aortic stenosis in patients at low surgical risk.

As a result, a team of investigators, led by Raj R. Makkar, MD, Cedars-Sinai Heart Institute, observed no significant difference in mortality or stroke at 30 days or 1 year in patients who underwent TAVR for bicuspid or tricuspid aortic stenosis.

Methods

The team evaluated all consecutive patients who underwent TAVR with contemporary balloon-expandable transcatheter heart valves in the US from June 2015 - October 2020 in the study.

The primary population consisted of patients at low surgical risk undergoing TAVR, while the secondary population included all patients, regardless of surgical risk, undergoing TAVR for aortic stenosis.

Low surgical risk was defined as a STS president risk of mortality score of <3%, with higher scores indicating higher risk of death within 30 days after surgery.

Primary outcomes included the rates of death and stroke at 30 days and 1 year. Moreover, secondary outcomes included procedural and in-hospital outcomes, echocardiographic outcomes, functional status, and health status.

The team used propensity score-based matching to account for differences between patients with bicuspid and tricuspid aortic stenosis. These were calculated using logistic regression based on 29 baseline patient characteristics, including age, sex, BMI, and aortic valve type as the dependent variable.

Results

Through the study inclusion period, a total of 159,661 patients underwent TAVR for aortic stenosis with balloon-expandable transcatheter heart valves at 684 institutions in the US.

Of this population, 37,660 patients were included in the analysis, consisting of 3243 patients with bicuspid aortic stenosis and 34,417 patients with tricuspid aortic stenosis were included in the analysis.

After propensity-score matching of patients with bicuspid and tricuspid aortic stenosis, 3168 low surgical-risk pairs and 6995 all-risk pairs were generated. Data show the proportion of patients with bicuspid aortic stenosis undergoing TAVR showed an increase from 2.8% in 2015 to 6.8% in 2020.

Analysis of the low-surgical risk pair show a mean age of 69 years and 69.8% men, with a 1.7% STS-predicted risk of mortality for both bicuspid and tricuspid aortic stenosis.

Further, no significant difference was shown between the rates of death in the bicuspid and tricuspid group at 30 days (0.9% versus 0.8%; hazard ratio, 1.18, 95% CI, 0.68 - 2.03, P = .55) and at 1 year (4.6% versus 6.6%; HR 0.75, 95% CI, 0.55 - 1.02, P = .06).

Additionally, no significant difference was found in the rate of stroke in either group at 30 days (1.4% versus 1.2%; HR. 1.14; 95% CI, 0.73 - 1.78, P = .55) and at 1 year (2.0% versus 2.1%; HR, 1.03, 95% CI, 0.69 - 1.53, P = .89).

Moreover, no significant differences were observed between the 2 groups in procedural complications, valve hemodynamics (aortic valve gradient: 13.2 mm Hg versus 13.5 mm Hg) and moderate or severe paravalvular leak (3.4% versus 2.1%).

Conclusion

The study concluded no significant difference in mortality or stroke was observed in patients treated with TAVR for bicuspid versus tricuspid aortic stenosis.

However, they noted that patient selection may have played a role in the efficacy and safety outcomes of this present study.

“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,” investigators wrote.

The study, “Association Between Transcatheter Aortic Valve Replacement for Bicuspid vs Tricuspid Aortic Stenosis and Mortality or Stroke Among Patients at Low Surgical Risk,” was published online in JAMA.