Transaxillary TAVR emerges as top alternative to femoral access

Transsubclavian or transaxillary (TAx) access has become the preferred route for balloon-expandable TAVR when femoral access isn’t feasible, a new study found. Outcomes were generally favorable with TAx TAVR compared to other alternative access techniques, with the exception of higher stroke rates, researchers reported in JACC: Cardiovascular Interventions.

“Unlike the iliofemoral artery, which tends to calcify with age, the axillary/subclavian artery is surprisingly resistant to calcification,” Vinayak Bapat, MS, DNB, and Gilbert H.L. Tang, MD, MBA, wrote in a related editorial. “This may explain why patients with advanced peripheral vascular disease, even aortoiliac occlusive disease, may be amenable to TS (transsubclavian) TAVR.”

Still, nonfemoral access is only used in 6% to 10% of patients in the U.S., Bapat and Tang noted. But TAx appears to be overtaking transapical (TA) and transaortic access (TAo) as the most popular form of nontransfemoral TAVR, at least for balloon-expandable valves.

Thom G. Dahle, MD, with Centracare Heart & Vascular Center in St. Cloud, Minnesota, and colleagues studied data from 63,581 patients from the Transcatheter Valve Therapy Registry who underwent TAVR with the Sapien 3 valve (Edwards Lifesciences) from June 2015 through February 2018. Of that number, 3,628—or 5.7%—had nontransfemoral access, with TAx comprising 34.4% of those patients.

Notably, the proportion of nontransfemoral patients who underwent TAx TAVR increased from 20.2% in the third quarter of 2015 to 49% in the fourth quarter of 2017. Meanwhile, TA or TAo access decreased from 61.9% to 35.3% over that same period.

The researchers propensity-matched 1,180 pairs of patients based on baseline characteristics to study how access route (TAx versus TA or TAo) was associated with outcomes.

Those undergoing TAx TAVR showed a lower risk of 30-day mortality (5.3% vs 8.4%), new-onset atrial fibrillation (2% vs 13%) and 30-day hospital readmission (11.6% vs 15.1%). Their median length of stay in the hospital was half the total for TA of TAo procedures at three days instead of six, and median time spent in the ICU was also shorter (26.3 hours vs 47 hours).  

However, stroke rates were 6.3% for TAx TAVR and 3.1% for transapical or transaortic TAVR.

“This is the first registry data to compare traditional transthoracic alternative TAVR (TA and TAo) with TAx TAVR,” Dahle et al. wrote. “Our results showed that TAx access had lower mortality, shorter ICU and hospital stays, but a higher stroke rate. With further understanding of stroke mechanism, it is expected that the number of TAx TAVR procedures will continue to grow as the second most used access route for TAVR.”

The positive results came in spite of 78.2% of the included facilities performing five or fewer TAVRs with that approach over the study period.

“Despite the lack of experience, procedural success with TAx TAVR was quite high (97.4%), and the vascular complication rate was only 2.5% in this high-risk, vasculopathic population,” Dahle and co-authors wrote.

Although the benefit of cerebral embolic protection devices in this population remains inconclusive, both Dahle et al. and the editorialists noted it may be a strategy worth considering to potentially cut down on stroke rates.

“Further study of TAx TAVR with comparisons between other alternative approaches, including transcarotid or transcaval, is needed to understand whether the TAx approach should be the preferred alternative when femoral access is not available,” Dahle and colleagues wrote.