Surgical or Transcatheter Aortic-Valve Replacement in Intermediate-Risk Patients (SURTAVI Investigators)

Transcatheter aortic valve replacement (TAVR) is superior to medical therapy in inoperable patients with severe, symptomatic aortic stenosis (AS), and may be the preferred option in high-risk surgical patients. The comparative efficacy of TAVR and surgical aortic valve replacement (SAVR) in intermediate risk AS patients has been less well studied. The PARTNER 2 randomized trial showed non-inferiority of balloon expandable TAVR compared to SAVR in intermediate risk patients at 2 years. In the Surgical Replacement and Transcatheter Aortic Valve Implantation (SURTAVI) trial, a self-expandable TAVR prosthesis (Medtronic’s CoreValve [84%] and Evolut R [16%]) was randomized against SAVR in 1660 intermediate risk patients. The primary endpoint was a composite of death from any cause and disabling stroke at 24 months. The mean age was 79.8±6.2 years with an average Society of Thoracic Surgeons (STS) estimated risk of death of 4.5±1.6%. At 24 months, the TAVR group was non-inferior to the SAVR group for the primary endpoint (12.6% vs. 14.0%, posterior probability of non-inferiority, >0.999). Rates of both individual components of this endpoint were also similar. TAVR, compared to surgery was associated with lower rates of acute kidney injury (1.7% vs. 4.4%), atrial fibrillation (12.9% vs. 43.4%), and transfusion requirements (12.5% vs. 41.1%), but higher rates of residual aortic regurgitation (5.3% vs. 0.6%) and need for pacemaker implantation (25.9% vs. 6.6%).

Conclusions
While the trials migrate across risk spectrum and prosthesis type, short term outcomes with TAVR are equivalent to, if not better than, SAVR. Two large industry-sponsored randomized trials of TAVR vs SAVR in low surgical risk individuals are currently on-going and are sure to be scrutinized closely. Evidence for transcatheter valve durability remains a critical unknown that will need to be addressed prior to full-scale adoption of TAVR as first-line therapy in younger individuals.
Reardon MJ, Van Mieghem NM, Popma JJ, et al., for the SURTAVI Investigators. Surgical or Transcatheter Aortic-Valve Replacement in Intermediate-Risk Patients. N Engl J Med 2017;376:1321-31.

 

Enrique Zolezzi, James M McCabe

University of Washington, Division of Cardiology