Downsizing, Underexpansion Common in Redo TAVI With Sapien 3

During valve-in-valve TAVI procedures using the Sapien 3 balloon-expandable valve (Edwards Lifesciences) as the second prosthesis, downsizing and underexpansion are frequently observed, particularly when the initial valve was an Evolut (Medtronic), a small study indicates.

This may result in suboptimal hemodynamics, potentially affecting long-term durability of the transcatheter heart failure and patient outcomes, Alejandro Travieso, MD (Rigshospitalet, Copenhagen University Hospital, Denmark), and colleagues suggest in a research letter published online this week in JACC: Cardiovascular Interventions.

These findings, though preliminary, indicate that “we are not fully understanding yet what the best strategy is for redo TAVR,” senior author Ole De Backer, MD, PhD (Rigshospitalet, Copenhagen University Hospital), told TCTMD. What is still missing, he added, is information about “what valve type, which valve size, and which valve position will result in the best outcome for revalving of a TAVR device.”

This study, he continued, “was a first small attempt to increase the knowledge in this field, but clearly, there is more needed to fully understand what the better redo TAVR strategies will be in the future.”

There is indeed plenty of evidence for TAVI when used to treat native aortic stenosis, but there are limited data—beyond bench testing—when it comes to redo or valve-in-valve procedures, De Backer said. And although redo TAVI is becoming more common as the procedure becomes increasingly used in younger patients and/or those with longer life expectancies, volumes remain very low.

To start to fill the evidence gap around redo TAVI, he and his colleagues examined postprocedural cardiac CT scans—which give “very valuable insight in how these valves interact,” De Backer said—from 30 consecutive patients who underwent redo TAVI:

• 14 treated with a Sapien 3 implanted in a Sapien 3
• 10 treated with a Sapien 3 implanted in a low position in an Evolut
• Six treated with a Sapien 3 implanted in a high position in an Evolut

Overall, the researchers found that downsizing Sapien 3 during the redo procedures occurred in seven cases (23%). This was most common when a Sapien 3 was placed in a high position in an Evolut (66.7% of cases).

Undersizing is common because “very often these first index TAVR devices are less expanded than we anticipate,” De Backer explained. “Another important factor is, of course, that if you do revalving of the Sapien in an Evolut, especially in a high position, you are revalving in the waist of the Evolut, which is a narrower part of the valve.”

The investigators also frequently observed underexpansion of the redo Sapien 3 valve when placed into an Evolut, particularly when the implant position was low. In addition, deformation and eccentricity of the redo Sapien 3 valve was worse when the initial valve was an Evolut, which could have contributed to the impaired hemodynamics (ie, mean gradients) seen in this situation. Effective orifice areas were lowest in Sapien 3-in-Evolut configurations as well.

“The problem with underexpansion of a Sapien device is that you get leaflet pinwheeling, and leaflet pinwheeling can result in worse valve hemodynamics,” De Backer said. “So that’s something you want to avoid.”

The study emphasizes “that it’s really mandatory that if you plan for a redo TAVR, that you at least do a CT scan of your post-index TAVR” and not base decisions simply on what is in the patient’s medical record regarding the initial procedure, he said. Care should also be taken to maintain coronary access as well, he added.

There are additional tools available to help operators in this situation, said De Backer, including the Redo TAV smartphone app developed by Vinayak Bapat, MD. He added, too, that simulations may be helpful when it comes to procedural planning in redo TAVI.