Patients who tend to have smaller heart valves and a tighter gap where the organ connects to the outgoing aorta—a group that mostly includes women—also tend to see additional complications after replacing their aortic valve with a minimally invasive implant.
That includes losses in the new valve’s performance and durability, as well as an increased risk of the implant not properly fitting within the patient’s anatomy—where size mismatches can lead to higher rates of heart failure, reduced quality of life and earlier deaths.
Now, data from the largest randomized trial to compare to the two most-used transcatheter aortic valve replacements in the U.S. head-to-head—Medtronic’s Evolut family and Edwards Lifesciences’ Sapien platform—is also the first to take a closer look at primarily women.
The study, known as SMART, included 716 international patients with a small aortic annulus, about 87% of whom were women. After one year, Medtronic’s Evolut was shown to perform on par with Edwards’ Sapien in terms of clinical safety—with each TAVR system offering similar composite rates tallying patient deaths, disabling strokes or rehospitalizations for heart failure.
However, Evolut’s self-expanding structure delivered superior results in measures of valve function, compared to Sapien’s balloon-powered frame, in what Medtronic described as a landmark trial.
The rate of bioprosthetic valve dysfunction through 12 months was 9.4% in the Evolut arm—with its Pro, Pro+ and FX models—far below the 41.6% seen with the Sapien 3 and 3 Ultra valves. That includes cases of structural valve deterioration and calcification, as well as the formation of blood clots or bacterial infections.
The trial’s results were presented as a late-breaking study at the annual scientific session of the American College of Cardiology in Atlanta and were simultaneously published in the New England Journal of Medicine.
“This was a bold decision—you don’t see many head-to-head trials in healthcare,” Medtronic CEO Geoff Martha said this week during a company call with investors. “We had that kind of confidence in the technology, but we also thought it was important to highlight this underrepresented cohort of people.”
According to Medtronic, while women statistically may have longer life expectancies, they see higher rates of death compared to men following a diagnosis of severe aortic stenosis, even when accounting for differences in age. The company also recently presented survey results showing lower rates of heart disease screening and awareness of aortic stenosis among older women.
“We had two goals for this trial,” said Nina Goodheart, president of Medtronic’s structural heart and aortic valve business. “The first was to take the two most commonly used valve platforms—the Evolut platform and the Sapien platform—and compare them in this very large small annulus patient population, 90% of which are women, and see whether or not we could truly see significant benefits. I think what you saw today was unequivocally yes.”
“The second thing we wanted to do was to think about that small annulus patient and to think about… how women present differently,” Goodheart added. “When I think about someone who looks like me, how could they possibly be treated the same?… We had no data to show that there was an optimal treatment for somebody my size versus somebody larger. We now have that with this trial.”
“That’s hugely important, hugely impactful—and it has to raise the question now in every heart team, that when a female patient is put up for discussion of what TAVR valve to get, we now have answered the question on what’s the optimal TAVR valve for this patient population.”
Medtronic estimates that 40% of all TAVR patients worldwide may have a small aortic annulus, as well as about 35% of patients that receive a Sapien valve in the U.S. The medtech giant believes it can now chip away at that market share a little better, supported by the recent FDA approval of its most recent Evolut valve, the FX+.
While largely the same in structure as the previous FX, its successor—slated for a U.S. rollout this summer—features larger windows in its nitinol frame, designed to provide an easier path for clinicians looking to pass through catheters to the heart’s coronary arteries during future procedures. Medtronic also said that will become especially important as TAVR valves move into younger patients who may need additional cardiac interventions.