Self-expanding TAVR linked to aortic regurgitation, 1-year mortality

Data from the FRANCE 2 registry indicated that self-expandable vs. balloon-expandable transcatheter aortic valve replacement independently predicted a post-procedural aortic regurgitation grade of at least 2, which was the strongest predictor of 1-year mortality.

The researchers of the study suggested that TAVR has been associated with significant post-procedural aortic regurgitation in about 10% to 20% of patients. However, predicting this complication in balloon-expandable and self-expandable TAVR has challenged the clinical community.

The current analysis included 3,195 TAVR procedures performed in consecutive patients from 34 hospitals in France. The study cohort was comprised of 2,769 eligible participants from this population who underwent post-procedural transthoracic echocardiography.

The median follow-up duration was 306 days.

There were 1,872 balloon-expandable and 897 self-expandable devices implanted. Around three-quarters of the devices (75.3%) were implanted femorally.

The researchers reported that post-procedural aortic regurgitation ≥ grade 2 occurred in 15.8% of the overall population and more frequently in the self-expandable group than in the balloon-expandable group (21.5% vs. 13.0%; P=.0001).

Multivariate analysis results indicated that the self-expandable device independently prognosticated post-procedural aortic regurgitation ≥ grade 2.

Among eight independent predictors of aortic regurgitation ≥ grade 2 for the balloon-expandable procedure, femoral delivery (P=.04), larger aortic annulus (P=.0004) and smaller prosthesis diameter (P=.0001) were among the most significant. Femoral delivery (P=.0001) was highlighted as an independent predictor of this grade of aortic regurgitation in the self-expandable group. Aortic annulus and prosthesis diameter failed to predict post-procedural aortic regurgitation in the self-expandable group, according to the results.

One-year mortality was predicted by post-procedural aortic regurgitation ≥ grade 2, but not grade 1, for both the balloon-expandable (HR=2.50; P=.0001) and self-expandable (HR=2.11; P=.0001) groups.

The mortality rate for patients with aortic regurgitation ≥ grade 2 at baseline who had this same level of regurgitation post-procedure was 7% at 1 year. However, post-procedural aortic regurgitation ≥ grade 2 yielded a mortality rate of 43% in patients with renal failure, 31% in those with aortic regurgitation < grade 2 at baseline, 35% in those with low transaortic gradient and 45% in those who underwent non-femoral delivery.

E. Murat Tuzcu

E. Murat Tuzcu, MD, Samir R. Kapadia, MD, and Lars G. Svensson, MD, PhD, of the Heart and Vascular Institute at the Cleveland Clinic, wrote an accompanying editorial in which they suggested that the current findings are concordant with previous research. They highlighted several studies that showed aortic regurgitation is more frequent in self-expandable procedures. However, they suggested that many of the datasets suffer from a lack of a randomized comparison group.

Tuzcu and colleagues highlighted the increased frequency of transfemoral access compared with non-transfemoral access in the current study. “One possible reason can be the variation of the valve placement. It is possible that the control of deployment is better if vascular access is closer to the aortic valve,” they wrote, and suggested that this access allows for better co-axial deployment and less regurgitation, “although this is conjectural at this time.”

Another possibility, according to Tuzcu and colleagues, is that non-transfemoral access is restrictive for the size of the implant, which could lead to less likelihood of error on the small valve size. “This bias may result in lower ‘cover index’ and more [aortic regurgitation] although it was not studied in the current study,” they wrote. “The implication is that a smaller valve is inserted via the [transfemoral] route that may not seal as well.”

Tuzcu and colleagues also suggested that paravulvular aortic regurgitation is clinically important, with most effects seen in patients with multiple comorbidities and no previous history of aortic regurgitation. “The registry data is a powerful component of our collective information base as long as we maintain the highest quality of the data that is collected,” they wrote. “Yet, we still need the appropriately controlled studies to understand the comparative effectiveness of the new generation transcatheter valves; the ideal would be randomized controlled trials.”

For more information:

Van Belle E. Circulation. 2014;doi:10.1161/circulationaha.113.002677.

Tuczu EM. Circulation. 2014;doi:10.1161/circulationaha.114.008748.

Disclosure: The researchers report financial disclosures with Abbott, Bayer, Boehringer Ingelheim, Edwards Lifesciences, Medtronic and St. Jude Medical. The editorialists report no relevant financial disclosures.