Women More Likely to be Alive 1 Year After TAVR: STS/ACC TVT Registry

Once again, a new analysis of men and women undergoing transcatheter aortic valve replacement is highlighting the differences in baseline and clinical characteristics between the sexes while confirming the significant survival advantage for women undergoing the procedure when compared with their male counterparts.

The analysis is the latest in a growing number of studies to cement the unique advantages a transcatheter approach appears to have in the treatment of aortic stenosis in women.

Using data from the TVT Registry of the Society of Thoracic Surgeons/American College of Cardiology, researchers report that 21.3% of women had died at 1 year compared with 24.5% of men (adjusted HR 0.73; 95% CI 0.63-0.85). The mortality difference was observed despite female patients being older, experiencing more in-hospital vascular complications, and showing a trend toward more bleeding.   

“These data underline the importance of sex differences in this arena and why we need to study women on their own when comparing [surgical] AVR versus TAVR,” senior investigator Roxana Mehran, MD (Icahn School of Medicine at Mount Sinai, New York, NY), told TCTMD in an email.

In an editorial accompanying the study, Molly Szerlip, MD (The Heart Hospital Baylor, Plano, TX), states that the data confirm the sex-based differences observed in randomized clinical trials, which suggests those trial results are generalizable to the treated population after commercial approval. The data, however, should not be extrapolated to lower-risk patient populations or to patients who receive next-generation valves.

Although the exact reasons for the survival benefit in women is unknown—particularly since it is men who have a survival benefit after surgical AVR—Szerlip writes that “as it stands now, being female is truly an advantage.”

Fewer Comorbidities for Female Patients

The analysis, published online today ahead of print in the Journal of the American College of Cardiology, included 11,808 women and 11,844 men who underwent TAVR between 2011 and 2014. The average age of the female and male patients was 82.3 and 81.7 years, respectively.

Overall, female patients were less likely to have coronary artery disease, atrial fibrillation, and diabetes, but they were more likely to have a porcelain aorta, a lower glomerular filtration rate, and a higher mean STS score (9.0% for women vs 8.0% for men; P < 0.001). Women were also more likely to have moderate-to-severe mitral regurgitation. Men had more left ventricular dysfunction than women and a higher prevalence of peripheral vascular disease. Transfemoral access was performed in 65% of male patients versus 55% of female patients.

In-hospital complications occurred in 8.3% and 4.4% of female and male patients, respectively. Bleeding occurred in 8.0% of women and 6.0% of men, a difference that trended to statistical significance (P = 0.06). Despite these differences, all-cause mortality at 1 year, as noted, favored women. The was a trend toward a higher 1-year risk of stroke among women, but the difference was not significant. The combined endpoint of death/MI favored female patients, but the difference in MI between men and women was not significant at 1 year.

The researchers, including lead investigator Jaya Chandrasekhar, MBBS (Icahn School of Medicine at Mount Sinai, New York, NY), note that 66% of women achieved a valve cover index ≥ 8% compared with 54% of men.

In her editorial, Szerlip notes that most patients in the registry were treated with the balloon-expandable valve (Sapien, Edwards Lifesciences) and that the second-generation Sapien XT 29-mm valve was not available for most of the study period. As a result, only 12% of men received the 29-mm valve.

“This factor could have adversely affected male survival by causing both a higher incidence of patient prosthesis mismatch and significant paravalvular leak,” she writes. “Lastly, there may be a difference in the myocardial structural changes between sexes because female patients are known to undergo greater regression of left ventricular hypertrophy after aortic valve replacement than male patients.”

Note: Mehran and co-author George D. Dangas, MD, PhD, are faculty members of the Cardiovascular Research Foundation, the publisher of TCTMD.