Study finds Evolut R TAVR device is safe, effective at 30 days in high-risk patients

A prospective, single-arm, non-randomized study found that the CoreValve Evolut R device was safe and effective in the short-term in patients with severe aortic stenosis who underwent transcatheter aortic valve replacement (TAVR).

At 30 days, the all-cause mortality rate was 2.5 percent, while 3.3 percent of patients had disabling stroke, 7.5 percent had major vascular complications, 7.1 percent had life-threatening or disabling bleeding and 16.4 percent had new permanent pacemakers.

All of the patients were considered at least high risk for surgery.

Lead researcher Jeffrey J. Popma, MD, of Beth Israel Deaconess Medical Center in Boston, and colleagues published their results online in JACC: Cardiovascular Interventions on Feb. 13.

Medtronic, which manufactures the CoreValve Evolut R, funded the study. The FDA approved the Evolut R in June 2015 in 23 mm, 26 mm and 29 mm sizes for patients with severe aortic stenosis who are at high or extreme risk for surgery. In October 2016, the agency expanded the approval the device in a 34 mm size.

The researchers mentioned that TAVR has become common in patients with severe aortic stenosis who are at increased risk for surgical aortic valve replacement.

In this trial, known as the CoreValve Evolut R U.S. Clinical Study, the researchers enrolled 241 patients at 23 sites in the U.S. All of the patients had severe, symptomatic aortic stenosis who were deemed to be at high to extreme risk for surgery.

The mean age of patients was 83.3 years old, and the mean Society of Thoracic Surgeons predicted risk of mortality was 7.4 percent. In addition, 237 of the 241 patients underwent TAVR from September 2014 to July 2015.

The researchers noted that they used an iliofemoral access route in 89.5 percent of cases and that 80.7 percent of cases were performed using general anesthesia. None of the patients had an MI, while resheathing or recapturing was performed in 22.6 percent of patients. In addition, 63.7 percent of patients were implanted with a 29 mm device, 35 percent were implanted with a 26 mm device and 1.3 percent were implanted with a 23 mm device.

Of the six deaths during the study, three occurred within the first 24 hours, including two due to aortic dissection and one related to left ventricular perforation. The researchers added that other deaths occurred at day 3 (cardiac arrest following procedural valve in valve and possible stroke), day 5 (retroperitoneal hematoma and respiratory failure) and day 13 (post-procedural left bundle branch block and sudden death while asleep).

At 30 days, there were also significant improvements in aortic valve hemodynamics, including a reduction in mean aortic valve gradient and increase in aortic valve area. No patients had severe paravalvular leaks, while 5.3 percent had moderate residual paravalvular leaks.

The study had a few limitations, according to the researchers, including that it only included patients with perimeter-based diameters between 18 and 26 mm. They also did not examine the effect of annular and left ventricular outflow tract calcification on the frequency of residual aortic regurgitation.

“We conclude that this novel self-expanding transcatheter bioprothesis is safe and effective for the treatment of severe aortic stenosis in patients who are suboptimal for surgery,” the researchers wrote. “The reduced profile allows more patients to be treated with transfemoral access with low rates of vascular and bleeding complications. The ability to reposition the device during deployment allows more precision positioning, resulting in reduced rates of residual aortic regurgitation and conduction disturbances requiring permanent pacemaker placement.”