How to evaluate risk when TAVR patients require surgery later in life

Operative mortality for isolated SAVR after TAVR has declined substantially as operators gain more experience, while the newly developed risk model showed excellent accuracy for all patients and surgical procedures. The study also found that a large portion of TAVR explant cases that can be defined as low surgical risk had outcomes that compared very favorably to valve-in-valve TAVR data.

TAVR is being used more and more to treat younger patients, and there is a question on how long these valves will last before they need to be replaced. The additional hardware and leaving the native valve in place means there is less room for additional TAVR devices, so surgeons argue younger patients should receive a surgical valve and keep TAVR as an option later in life.

“We have shown that surgically removing TAVR valves carries a higher risk than a first-time surgical AVR. Our study showed that surgeons are improving with experience, that the risk of TAVR explant is decreasing, and that we can now predict—with very good accuracy—the risk of surgical TAVR explant for individual patients.” Hawkins said.

Unlike an earlier STS model that focused only on isolated SAVR after TAVR, the new calculator incorporates a wide range of concomitant procedures frequently required in these patients. Hawkins said nearly 60% of patients in the database underwent additional procedures beyond valve replacement, including treatment for coronary artery disease, mitral valve disease, aortic pathology and atrial fibrillation.

The expanded model gives heart teams a more complete picture of surgical risk, allowing them to compare surgery with alternative strategies such as redo TAVR.

"We're able to provide this more comprehensive assessment," Hawkins explained. "It allows the heart team to understand from a surgical perspective what the risks of the surgery might be."

The calculator may be particularly valuable as clinicians consider the broader benefits of surgery. Patients with concomitant atrial fibrillation, for example, may undergo surgical ablation procedures that have been associated with improved long-term survival.

"Part of the heart team discussion can be maybe you want to redo TAVR, but a clip and an ablation; a surgical approach has all of these additional benefits that might be worth it," Hawkins said. "But we really need to know that upfront risk."

Surgical outcomes are improving

One of the study's most encouraging findings is that outcomes for isolated SAVR after TAVR have improved substantially as centers gain more experience with TAVR explant procedures.

According to Hawkins, mortality rates for isolated SAVR after TAVR have fallen from approximately 13% in the earliest era of TAVR explants to about 3.5% in more recent years among carefully selected patients.

"That risk has come way down. In the most recent era, it's only 3.5% mortality, and that's comparable to repeat TAVR," he said.

High-risk patients who got TAVR are now low-risk surgical candidates

Another trend that is reshaping conversations with patients is how the use of TAVR in high-risk surgical patients appears to be helping them become low-risk surgical candidates later on when they need a new valve replacement. Many of those patients are now years older but may still qualify as low-risk surgical candidates under contemporary risk assessments.

"We're seeing patients who were in the moderate-risk TAVR trials and now get a predicted risk score that's 2% and are technically low risk," Hawkins said.

The findings underscore the importance of viewing valve disease through a lifetime-management lens, particularly as TAVR use expands into younger populations.

"Patients are realizing we really do need lifetime management," Hawkins said. "You can't just put 15 TAVRs in there."

Durability of valves remain a big question

A major challenge facing clinicians is the lack of long-term durability data for transcatheter valves.

While structural valve degeneration is becoming more common as first-generation TAVR recipients age, Hawkins said it is only one of several failure mechanisms. Other causes of TAVR explant include infective endocarditis, aortic insufficiency and paravalvular leak.

The timing of those failures can also vary significantly, making risk prediction difficult. Although current estimates suggest bioprosthetic surgical valves in patients aged 65 to 80 typically last 10 to 15 years, Hawkins cautioned that more data are needed to understand whether transcatheter valves will ultimately match surgical valve durability.

Some 5-6 year data from TAVR trials suggested certain transcatheter valves might outlast surgical bioprosthetic valves. But more recent analyses are raising concerns that some TAVR devices may demonstrate slightly worse durability over time, though the differences remain relatively small.

While there is currently a debate about reducing registry requirements and heart team infrastructure, Hawkins argued that continued data collection is essential.

"We don't have the answers yet," he said. "We need to work with surgeons. We need to work with cardiologists. We need to all come together because without the data, or we won't ever have the answers."