Study Shows Need for TEVAR Devices Specifically Suited for Women's Anatomy

January 7, 2014—The Society for Vascular Surgery (SVS) announced the publication of a study indicating that women are more likely than men to experience complications from thoracic endovascular aortic repair (TEVAR) because the current devices are too large for women’s anatomy. George J. Arnaoutakis, MD, et al published the study in SVS’s Journal of Vascular Surgery (2014;59:45–51). 

“This study is a call to action to decrease device size to improve outcomes for women,” commented study investigator Christopher Abularrage, MD, in the SVS press release. Dr. Abularrage, who is Assistant Professor of Surgery at Johns Hopkins University, added, “With the device size of TEVAR delivery systems and women’s generally smaller iliac arteries, women are more likely to have complicated access issues that directly result in increased blood loss and death.”

According to SVS, the investigators reviewed data on TEVAR procedures that were performed between 2005 and 2011. They found that women were approximately three times as likely to require more invasive procedures, significantly increasing their risk of death. Additionally, women had longer TEVAR procedure times and were at greater risk for bleeding.

SVS noted that previous studies have shown that women are at greater risk for death after TEVAR, but until now, there has not been a well-designed study to identify the cause of this disparity between the sexes.

SVS President, Julie Freischlag, MD, who is Chair of the Department of Surgery at Johns Hopkins University and one of the study’s investigators, stated, “Everyone had an inkling, but now we have proof that device size is an issue. One of the early challenges in treating vascular disease in women was recognizing the illness—for a long time we believed being female protected against vascular disease. Now we’re past that and realize that there is a whole population of patients that could be treated better with devices better matched to their anatomy.”

In the Journal of Vascular Surgery, the investigators noted in the study background that previous studies have shown that female sex is associated with increased morbidity and mortality after endovascular abdominal aortic aneurysm repair. The goal of this study was to assess the effect of sex on 30-day outcomes after TEVAR using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database.

As summarized in the article, the investigators conducted a review of the 2005 to 2011 ACS-NSQIP database to identify all patients who underwent TEVAR for nonruptured thoracic aortic aneurysms. Procedure and diagnosis codes were used to capture the study population. Patients were stratified according to sex. Baseline, operative, and outcomes data were compared in a bivariate fashion. The primary outcome measure was 30-day mortality, and a risk-adjusted generalized linear model with Poisson distribution was used to identify relative risk.

During the study period, 649 patients (279 women [43%] and 370 men [57%] underwent TEVAR. Baseline demographics according to patient sex were similar; however, women were less likely to drink alcohol (1% vs 5%; P = .001) and to have a history of cardiac surgery (14% vs 27%; P < .001). 

Further, more women required iliac artery exposure (18% vs 7%; P < .001). Operative times (173.6 ± 6.3 minutes vs 159.8 ± 5.2 minutes; P = .03), transfusion rates (30% vs 17%, P = .001), and hospital length of stay (7.7 ± 0.5 days vs 7.6 ± 0.5 days; P = .009) were increased in women compared with men. 

Overall, postoperative complications were similar, but unadjusted mortality was significantly greater in women (6% vs 3%; P = .03). On multivariable analysis, female sex was no longer a significant predictor of mortality (relative risk [RR], 2.3; 95% confidence interval [CI], 0.99–5.34; P = .053). Independent predictors of 30-day mortality included older age (RR, 1.05; 95% CI, 1.01–1.09; P = .02), emergent procedure setting (RR, 3.76; 95% CI, 1.79–7.87; P < .001), and iliac artery exposure (RR, 4.42; 95% CI, 2.07–9.44; P < .001).

The investigators concluded that 30-day unadjusted mortality after TEVAR for nonruptured thoracic aortic aneurysms was higher in women compared with men, but this univariate finding did not persist after risk adjustment. Multivariable analysis showed that a need for iliac artery exposure, older age, and emergency surgery were independently associated with higher mortality rates. These results suggest a need for decreased device delivery sizes and improvements in endovascular technology, stated the investigators in the Journal of Vascular Surgery.