Reports of nearly 40 vascular trauma events – including 19 deaths– with the EnVeo R replacement heart valve delivery catheter prompted Medtronic (NYSE:MDT) this month to warn doctors not to force passage if the catheter meets resistance.
The EnVeo R device is used to deliver the Evolut R transcatheter aortic valve replacement via the femoral artery. Although the vascular trauma rate of 0.136% is lower than annular dissection and aortic disruption rates shown in a Journal of the American College of Cardiology registry (0.2% and 0.4%, respectively), Medtronic said the severity of the events triggered a “thorough investigation.”
Medtronic employees recreated 3D blood vessel models, spokesman Joey Lomicky told the Minneapolis Star Tribune.
“Through this research it was noted that complex anatomical configurations increase the risk of vascular trauma,” Joey Lomicky said. “The 3D modeling will also help for future iterations of the device as we better understand these complex patient anatomies.”
“When they looked at patients with vascular trauma, they noticed that there is a high mortality rate,” added Dr. Gregory Helmer, director of the University of Minnesota’s TAVR program. “They’re bringing this to light basically to just make everyone aware and improve the overall safety of the TAVR procedure.”
Patients with complex or weakened aortic anatomies run a greater risk of vascular trauma from the EnVeo R device, the company said in a letter to doctors. Physicians should use significant-enough magnification during the procedure to allow them to see the capsule tip’s position.
“If the delivery system tip is observed to bend in a different direction relative to the delivery system capsule, do not force passage. Instead, retract the delivery system into a straight portion of the descending aorta, re-orient it by rotating the delivery system 90 degrees, and carefully reinitiate passage,” Medtronic advised.
If “significant resistance” is met as the EnVeo R is advanced, the company told doctors to stop and assess the vascular system. If no damage is shown, they should retract the system into the straight descending aorta and consider their options: Re-orient and begin passage again, consider a stiffer guidewire, use another device entirely or look at another access method that doesn’t use the femoral artery.
“It’s pretty common sense, but I think they’re just trying to increase awareness of proper technique,” Helmer told the newspaper. “Sometimes people, if they meet resistance, they just push harder. And really what you need to do is back off.”
Medtronic said it plans to update the EnVeo R’s labeling “consistent with this communication.”
It’s not the 1st problem Medtronic has reported with the EnVeo R system, although no adverse events were involved in past events. A year ago the company recalled some 6,900 units after particulate matter turned up in some lots; in December 2014 the company pulled 62 units because the devices were not the same size as indicated on their boxes.
