Key points Is transcatheter aortic valve implantation (TAVI) noninferior to surgical aortic valve replacement (surgery) in patients aged 70 years or older with severe, symptomatic aortic stenosis and moderately increased surgical risk? Findings In this randomized clinical trial that included 913 patients at moderately increased surgical risk due to age or comorbidity, one-year all-cause mortality was 4.6% with TAVI versus 6.6% with surgery, a difference that met the prespecified non-inferiority margin of 5%. Meaning Among patients aged 70 years or older with symptomatic severe aortic stenosis and moderately increased surgical risk, TAVI treatment was noninferior to surgery with respect to all-cause mortality at 1 year. |
End-stage valvular aortic stenosis obstructs blood flow from the left ventricle to the aorta. Before the development of the heart-lung machine in 1953, apart from a few reports of direct fracture of the stenosed valve in a beating heart or with hypothermic cardiac arrest, there were no effective treatments to relieve outflow obstruction.
Beginning in the 1960s, the use of mechanical and then bioprosthetic heart valves led to a substantial improvement in the survival of patients with severe aortic stenosis. Over the next 60 years, there were progressive improvements in mechanical prostheses and in the material and design of bioprosthetic valves (from homografts to xenografts to stented surgical aortic valve prostheses).
Importance
Transcatheter aortic valve implantation (TAVI) is a less invasive alternative to surgical aortic valve replacement and is the treatment of choice for patients at high surgical risk. The role of TAVI in lower-risk patients is unclear.
Aim
To determine whether TAVI is noninferior to surgery in patients with moderately elevated surgical risk.
Design, environment and participants
In this randomized clinical trial conducted at 34 centers in the United Kingdom, patients were enrolled between April 2014 and April 2018 and followed until April 2019.
Interventions
TAVI using any valve with CE marking (indicating the valve’s compliance with all legal and safety requirements for sale in the European Economic Area) and any access route (n = 458) or surgical replacement of the aortic valve ( surgery; n = 455).
Main results and measures
The primary outcome was all-cause mortality at 1 year. The primary hypothesis was that TAVI was noninferior to surgery, with a noninferiority margin of 5% for the upper limit of the one-sided 97.5% CI for the absolute difference between groups in mortality.
There were 36 secondary outcomes (30 reported here), including length of hospital stay, major bleeding events, vascular complications, conduction disorders requiring pacemaker implantation, and aortic insufficiency.
Results
Among 913 randomized patients (median age, 81 years [IQR, 78 to 84 years]; 424 [46%] were women; median Society of Thoracic Surgeons mortality risk score, 2.6% [IQR, 2.0% to 3.4%]), 912 (99.9%) completed follow-up and were included in the noninferiority analysis.
At 1 year, there were 21 deaths (4.6%) in the TAVI group and 30 deaths (6.6%) in the surgery group, with an adjusted absolute risk difference of −2.0% (one-sided CI 97 .5%, −∞ to 1.2%; P < .001 for noninferiority).
Of the 30 prespecified secondary outcomes reported here, 24 showed no significant differences at 1 year.
TAVI was associated with a significantly shorter postprocedural hospitalization (median 3 days [IQR, 2 to 5 days] vs. 8 days [IQR, 6 to 13 days] in the surgery group).
At 1 year, there were significantly fewer major bleeding events after TAVI compared with surgery (7.2% vs 20.2%, respectively; adjusted hazard ratio [HR], 0.33 [CI]. 95%, 0.24 to 0.45]), but significantly more vascular complications (10.3% vs 2.4%; adjusted HR, 4.42 [95% CI, 2.54 to 7.71]) , conduction disorders requiring pacemaker implantation (14.2% vs. 7.3%; adjusted HR, 2.05 [95% CI, 1.43 to 2.94]), and mild (38.3% vs. to 11.7%) or moderate aortic insufficiency (2.3% vs. 0.6%) ( adjusted odds ratio for mild, moderate,
Conclusions and relevance Among patients aged 70 years or older with severe, symptomatic aortic stenosis and moderately increased surgical risk, TAVI was noninferior to surgery with respect to all-cause mortality at 1 year. |
Registration: ISRCTN57819173
