Clinical Pearls & Morning Reports
Published April 5, 2017
Reardon et al. conducted a study that compared the safety and efficacy of transcatheter aortic-valve replacement (TAVR) performed with the use of a self-expanding bioprosthesis with surgical aortic-valve replacement in patients who were deemed to be at intermediate risk for surgery. The mean age of the participants was 79.8 ±6.2 years, and most had coexisting illnesses.
Q: Is TAVR widely used for patients with aortic stenosis who are at high surgical risk?
A: The adoption of TAVR in patients with aortic stenosis at high risk for surgery has been rapid, as shown by enrollment in the ongoing Society of Thoracic Surgeons–American College of Cardiology Transcatheter Valve Therapy Registry. The comparative efficacy of TAVR and surgery has been less well studied among patients with aortic stenosis who are at lower surgical risk.
Q: What criteria are used to designate a patient as being at “intermediate” surgical risk?
A: In the trial by Reardon et al., eligible patients with symptomatic, severe aortic stenosis were determined by the local multidisciplinary heart team to be at intermediate surgical risk, which was defined as an estimated risk of 30-day surgical death of 3 to 15%, according to the criteria of the Society of Thoracic Surgeons Predicted Risk of Mortality (STS-PROM), as well as such nontraditional factors as coexisting illnesses, frailty, and disability.
A: Reardon et al. found that TAVR was statistically noninferior to surgery in patients who were deemed to be at intermediate surgical risk by a multidisciplinary heart team. The primary end point was a composite of death from any cause or disabling stroke at 24 months. The incidence of the primary end point at 24 months was 12.6% in the TAVR group and 14.0% in the surgery group (95% credible interval [Bayesian analysis] for difference, −5.2 to 2.3%; posterior probability of noninferiority, >0.999). At 24 months, the rate of death from any cause was 11.4% in the TAVR group and 11.6% in the surgery group (95% credible interval for difference, −3.8 to 3.3%); the rate of disabling stroke was also similar in the two groups.
A: Early (≤30 day) acute kidney injury stage 2 or 3 and new or worsening atrial fibrillation occurred more often in the surgery group than in the TAVR group, whereas major vascular complications and the need for permanent pacemaker implantation occurred more often in the TAVR group. Transfusions were more common in the surgery group than in the TAVR group, including an increase by a factor of 3.5 in the need for four or more red-cell units. Aortic-valve hemodynamics improved in both the TAVR group and the surgery group. The TAVR group had lower mean aortic-valve gradients and larger aortic-valve areas than did the surgery group. Moderate or severe residual paravalvular regurgitation was more common in the TAVR group at 1 year (5.3% in the TAVR group vs. 0.6% in the surgery group; 95% credible interval for difference, 2.8 to 6.8%).