TAVR non-inferior to SAVR in Low to Intermediate Risk Patients With Severe Aortic Stenosis: DEDICATE-DZHK6 Trial

By Christina Lalani on

Key Points

  • In the DEDICATE-DZHK6 trial, patients with a history of severe aortic stenosis who were ≥ 65 years old and low to intermediate risk for surgery were randomized to receive TAVR versus SAVR.
  • TAVR was noninferior to SAVR with respect to death from any cause or stroke at 1 year.
  • Patients who received a TAVR had improved secondary outcomes including lower rates of disabling stroke, cardiovascular death, bleeding and new-onset atrial fibrillation compared to those who received a SAVR 

Although the current ACC guidelines recommend transcatheter aortic valve replacement (TAVR) in patients with severe aortic stenosis who have high surgical risk, there ongoing debate about the use of transcatheter aortic valve replacement (TAVR) versus surgical aortic valve replacement (SAVR) in patients who are young and/or low risk. In the DEDICATE-DZHK6 trial, the investigators aim to compare outcomes between the “real-world” population of patients with severe aortic stenosis who receive TAVR versus SAVR. To be eligible for the trial, patients had to be 65 to 85 years old and have low or intermediate operative risk such that they were eligible for either TAVR or SAVR based on interdisciplinary heart team assessment. Patients with a history of a bicuspid aortic valve, prior cardiac surgery, other coronary/valvular disease that would require intervention, severely reduced left ventricular systolic function (LVEF < 20%) or recent stroke/intracranial bleeding in the past month were excluded. The primary endpoint was a composite outcome of mortality or stroke at one year with the goal of demonstrating non-inferiority. The secondary outcomes included all-cause death and disabling stroke. 

The trial enrolled 1414 patients across 38 centers in Germany and all patients were randomly assigned to receive TAVR versus SAVR. The mean age of enrolled patients was 74 years old and 42% of the population was female. The mean STS-PROM score was 1.8% in the TAVR group and 1.9% in the SAVR group. At 12 months, death or stroke occurred in 5.4% of patients who received TAVR compared to 10.0% of patients who received SAVR (HR: 0.53, 95% CI: 0.35-0.79, p < 0.001). There was also a lower risk of all-cause death at one year (2.6% versus 6.2%) among patients who received a TAVR compared to SAVR (HR: 0.42, 95% CI: 0.24-0.73). Patients who received a TAVR had improved performance on many secondary endpoints including lower rates of disabling stroke, cardiovascular death, bleeding and new-onset atrial fibrillation. However, these patients did have higher rates of vascular access site complications, new onset left bundle branch block and new permanent pacemaker implantation. 

One of the unique features of this trial is its attempt to mimic the real-world patient population with severe aortic stenosis. As Dr. Moritz Seiffert, an interventional cardiologist who serves as the coordinating investigator for the DEDICATE-DZHK6 trial notes, “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.” One limitation of the study is that patients were enrolled during the COVID-19 pandemic, which could have contributed to worsened outcomes among surgical patients. This population will be followed for five years and further analysis will be done to look at quality of life metrics and specific subgroups.