Global First: Chinese SEASON-AR Trial Demonstrates TAVR Efficacy in Pure Aortic Regurgitation

BEIJING—A landmark Chinese trial is reshaping how doctors think about treating patients with severe aortic regurgitation who can't undergo open-heart surgery, offering the first randomized evidence that a minimally invasive valve replacement can dramatically cut hospitalizations and improve outcomes in this high-risk population.

The SEASON-AR study, published in Circulation, represents a watershed moment for interventional cardiology. For years, physicians have faced a difficult dilemma: patients with pure aortic regurgitation—who often present with symptoms of heart failure—had limited options if they were deemed poor candidates for surgical valve replacement. Now, for the first time, there is randomized controlled trial data showing that transcatheter aortic valve replacement, or TAVR, can meaningfully improve their prognosis.

"This fills a critical gap in our evidence base," said the study investigators. The trial enrolled 212 patients across 18 centers in China, randomly assigning them to receive either the VitaFlow transcatheter valve system plus guideline-directed medical therapy, or medical therapy alone.

The results were striking. At one year, the composite endpoint of all-cause death, disabling stroke, or heart failure rehospitalization occurred in just 8.3% of patients in the TAVR group, compared with 24.8% in the medical therapy group—a 66% relative risk reduction.

Heart failure rehospitalization drove much of this benefit. Even when accounting for death as a competing risk, TAVR patients remained significantly less likely to be hospitalized for heart failure.

Functional outcomes also favored the intervention. At one year, 84.7% of TAVR patients were in NYHA functional class I or II—meaning they had minimal or no symptoms—compared with 62.4% of those receiving medical therapy alone. The TAVR group also walked significantly farther on the six-minute walk test. Echocardiographic imaging showed more pronounced reverse remodeling of the left ventricle in the TAVR group, with greater improvements in ejection fraction and global longitudinal strain.

By the Numbers: The SEASON-AR trial enrolled 212 patients with severe pure aortic regurgitation who were deemed high-risk for surgery or refused surgical intervention. The median age was 74 years, and 63.3% were male. The median STS-PROM score was 6.2%, with 30.5% of patients scoring 8% or higher—indicating substantial surgical risk.

But the trial also highlighted important safety considerations. The rate of permanent pacemaker implantation was 20.2% in the TAVR group, and major or life-threatening bleeding within 30 days occurred in 9.2% of patients. Two patients (1.9%) required emergency conversion to surgery due to aortic dissection or valve migration.

The elevated pacemaker rate reflects a technical challenge specific to pure aortic regurgitation. Unlike aortic stenosis, where calcium deposits help anchor the prosthetic valve, patients with pure regurgitation lack this calcification. To achieve stable anchoring, operators often need to implant the valve deeper, which can increase interaction with the heart's conduction system and raise the risk of heart block requiring a pacemaker.

The VitaFlow system—manufactured by MicroPort CardioFlow Medtech Corporation—was used in 97.1% of cases. The device features a near-cylindrical frame and a double-layer sealing skirt, which the investigators noted may help achieve anchoring in the non-calcified annulus and reduce paravalvular leak.

Procedural details revealed that all 105 completed TAVR procedures were performed via the transfemoral approach under general anesthesia. Operators recaptured or repositioned the valve in 32.7% of cases, and 9.6% required valve-in-valve implantation.

The trial's open-label design is a notable limitation—both physicians and patients knew which treatment was assigned, which could influence decisions about hospitalization. The sample size of 212 patients was also insufficient to detect differences in individual components of the primary endpoint, such as death or stroke. And because 64.8% of patients came from a single center, and only the VitaFlow platform was evaluated, the findings may not generalize to all TAVR systems or practice settings.

Still, the study represents a significant advance. Pure aortic regurgitation has long been an orphan condition in structural heart disease, with limited evidence to guide treatment decisions. The SEASON-AR trial provides the first randomized data supporting TAVR in this population, offering hope to patients who previously had few options beyond medical management.

The findings also underscore the rapid evolution of TAVR. Originally approved for patients with aortic stenosis who were too sick for surgery, the procedure has expanded to lower-risk populations and, now, to patients with pure regurgitation. Dedicated devices for pure aortic regurgitation—such as the JenaValve Trilogy, J-Valve, and Pioneer Valve—have shown technical success rates of 95% to 99% in prospective studies, but until SEASON-AR, none had randomized evidence demonstrating clinical benefit over medical therapy.

Looking ahead, longer-term follow-up will be critical to determine whether the early benefits of TAVR are sustained, and whether the procedure ultimately reduces mortality in this population. Future studies comparing different TAVR platforms and refining patient selection criteria will also be important.

For now, the SEASON-AR trial marks a turning point—proof that even in the absence of calcification, transcatheter valves can deliver meaningful clinical benefit to patients with severe aortic regurgitation who have no good alternatives.