TAVI not inferior to SAVR in low-risk patients with severe aortic stenosis

Use of transcatheter aortic valve implantation (TAVI) does not increase the risks and contributes to a decrease in the rates of death or stroke at 1 year in patients with severe aortic stenosis when compared with surgical aortic-valve replacement (SAVR), suggests a study presented at ACC.24.

“We can now provide strong data that in this low-risk patient population, you could very safely offer TAVR versus SAVR,” said one of the study authors Moritz Seiffert, MD, professor of cardiology at BG University Hospital Bergmannsheil, Ruhr University Bochum in Bochum, Germany, in a press release. [https://tinyurl.com/5xbz7nka]

Seiffert and his team performed a randomized noninferiority trial at 38 sites in Germany and assigned 1,414 patients (mean age 74 years, 57 percent men) with severe aortic stenosis at low or intermediate surgical risk to undergo TAVI (n=701) or SAVR (n=713). Participants had a median Society of Thoracic Surgeons risk score of 1.8 percent (low risk). [N Engl J Med 2024;doi:10.1056/NEJMoa2400685]

In addition, percutaneous- and surgical-valve prostheses were chosen based on operator discretion. A composite of death from any cause or fatal or nonfatal stroke at 1 year served as the primary endpoint.

The Kaplan‒Meier estimate of the primary endpoint was 5.4 percent and 10.0 percent in the TAVI and SAVR groups, respectively (hazard ratio [HR] for death or stroke, 0.53, 95 percent confidence interval [CI], 0.35‒0.79; p<0.001 for noninferiority). [Seiffert M, et al, ACC 2024]

Death from any cause was lower in patients who received TAVI than in those who underwent SAVR (2.6 percent vs 6.2 percent; HR, 0.43, 95 percent CI, 0.24‒0.73), as was the incidence of stroke (2.9 percent vs 4.7 percent; HR, 0.61, 95 percent CI, 0.35‒1.06). In addition, the rate of procedural complications was 1.5 percent and 1.0 percent in the TAVI and SAVR groups, respectively.

“Although we primarily tested for noninferiority, the magnitude of the difference surprised us,” Seiffert said. “Valve prosthesis selection based on individual patients’ anatomical and medical considerations may have played a role.” [https://tinyurl.com/5xbz7nka]

“In addition, the COVID-19 pandemic might have amplified the surgical risk,” he said. “In fact, the relative difference was comparable to previous studies, but the overall higher event rates and larger patient population may have led to these significant results.”

Other trials

The findings on the primary endpoint were consistent with those of the PARTNER 3 trial, while those on other secondary outcomes in the TAVI and SAVR groups were also similar with the results of earlier studies. [N Engl J Med 2019;380:1695-1705; Eur Heart J 2023;44:836-852]

Furthermore, <1 percent of patients in both treatment groups experienced aortic-valve reintervention, valve thrombosis, or endocarditis. The higher rates of residual aortic regurgitation among patients in the TAVI arm warrant a longer follow-up, according to Seiffert and colleagues.

In terms of early bioprosthetic-valve failure following TAVI, other studies did not find an increased likelihood when patients were followed for 8 years. [N Engl J Med 2023;389:1949-1960; J Am Coll Cardiol 2023;82:2163-2165; Eur Heart J 2021;42:2912-2919; Eur Heart J 2021;42:2912-2919; JAMA Cardiol 2022;7:1000-1008]

“What [the current finding] really adds to previous trials is that it mirrors clinical routine,” Seiffert said. “It’s completely industry independent, not focused on one particular device but comparing a catheter-based strategy to a surgical strategy overall. That makes it more applicable and aligned with the types of decisions physicians are making in their daily medical work.” [https://tinyurl.com/5xbz7nka]

“TAVR is less invasive; it’s usually performed under local anaesthesia, lasting 30‒60 minutes, and the convalescence is shorter than with open chest surgery,” he said.

“[These findings offer] a strong argument toward catheter-based treatment, at least for the 1-year timeframe of this study, in these patients,” Seiffert added.