Nearly two years after the FDA opened up minimally invasive aortic heart valve replacements to younger, healthier people more likely to make it through open surgery with fewer complications, Medtronic has delivered new safety data that aim to show the agency made the right decision.
Transcatheter systems such as Medtronic’s Evolut device were first designed to reach patients with too many risk factors or comorbidities to undergo a taxing open procedure, and to instead treat narrowing heart valves by threading the replacement up through the blood vessels from a smaller incision.
Now, the medtech giant has unveiled two-year outcomes from a randomized, head-to-head trial in low-risk patients, comparing its transcatheter aortic valve replacement system to the gold standard of open heart surgery.
The data showed Evolut’s approach was not inferior to surgery when it came to a combined rate of death or disabling stroke after the procedure, with 4.3% for TAVR and 6.3% for surgery.
“We know that TAVR has an advantage over surgery in certain near-term outcomes; however, in these low-risk studies, longer term outcomes are more important than ever,” said the study’s principal investigator, John Forrest, M.D., director of interventional cardiology at the Yale School of Medicine.
The study—presented at EuroPCR, the annual meeting of the European Association of Percutaneous Cardiovascular Interventions—also showed that the transcatheter valves maintained a slightly larger opening after two years, with stronger blood flow and less pressure buildup across the aortic valve.
In addition, Evolut also more often correctly matched valve orifice diameters with the patient’s body size, compared to open surgery.
“There are some clear differences in secondary outcomes, and the long-term impact in areas such as hemodynamics, pacemakers and prosthesis-patient mismatch will be important to follow,” Forrest said in a statement.
In August 2019, the FDA broadened its premarket approvals for Medtronic’s Evolut line of transcatheter valves, as well as Edwards Lifesciences’ Sapien system, to include aortic stenosis patients at all levels of surgical risk.
At the time, Medtronic had delivered TAVR clinical trial results spanning more than 1,400 patients, showing that people at low risk had seen shorter hospital stays and near-term improvements in quality of life.
The company also presented an adaptive, Bayesian statistical analysis of its Evolut data at the 2019 meeting of the American College of Cardiology, which predicted outcomes compared to open surgery out to two years based on 30-day and 12-month follow-up data.
That paper, published in The New England Journal of Medicine that year, estimated the incidence of combined mortality and stroke as slightly farther apart than the latest two-year results but still within non-inferior bounds, at 5.3% in the TAVR group and 6.7% from surgery.
“Results from this landmark study reassure us that the positive outcomes presented using the Bayesian statistical analysis at ACC.19, before the full two-year outcomes were available, matched the actual two-year outcomes and thus was an extremely accurate and scientifically rigorous methodology that researchers can feel confident about moving forward,” said Jeffrey Popma, vice president and chief medical officer for Medtronic’s coronary, renal denervation, structural heart and aortic businesses.
Popma was also co-principal investigator for the Evolut Low Risk Trial and the NEJM paper while serving as director of interventional cardiology at Beth Israel Deaconess Medical Center.