Early Redo TAVI Outcomes Look Good, but ‘Far From Definitive’

Operators can achieve equally good clinical outcomes when performing redo TAVI in patients with a failing balloon- or self-expandable transcatheter aortic valve (TAV), according to new registry data.

In selected patients enrolled in the international Redo Registry, the initial and subsequent valve type used as part of the TAV-in-TAV had no impact on safety or mortality, report investigators. However, use of the self-expanding valve for the redo TAVI was associated with greater device success, driven by lower residual gradients compared with balloon-expandable transcatheter valves.

Lead investigator Uri Landes, MD (Wolfson Medical Center, Holon, Israel), said there is a growing awareness that younger, lower-risk patients with longer life expectancies will live beyond the valve’s life span, making TAV-in-TAV procedures more common going forward. “We know that valve-in-valve—a transcatheter valve inside of a surgical tissue valve—is a practical management strategy for many patients, but now it’s important to see whether or not TAV-in-TAV is an option as well,” Landes told TCTMD.

In terms of the new findings, it’s “comforting” to know that the initial implanted device doesn’t impact TAV-in-TAV outcomes to a great extent, he said. “It’s the second valve that makes the difference,” Landes told TCTMD, although adding that difference was solely in terms of valve hemodynamics.

What we can say is that in these selected patients, the outcomes are quite reassuring. Uri Landes

Guilherme Attizzani, MD (UH Cleveland Medical Center, OH), who wasn’t involved in the new study, agreed that long-term patient management is now at the forefront of physicians’ minds when they treat patients with severe symptomatic aortic stenosis. For that reason, these new data are a welcome addition.

“We need to understand our ability to be able to redo the procedure down the road, mostly in these younger, lower-risk patients that we’re treating now,” he told TCTMD. “We didn’t have this challenge when the therapy started, but our responsibility as operators has increased. We not only have to make sure we can deliver great results right now, but also be able to intervene in patients in the future.”

Many Configurations, Permutations

One of the issues with understanding the safety and feasibility of TAV-in-TAV is that there are a number of device permutations possible based on the patient’s initial and subsequent valve types. The unique configuration of the valves could potentially result in differing performance and safety that could impact device selection for redo procedures, said Landes.

The new study, which was published July 13, 2022, in JACC: Cardiovascular Interventions, included 221 propensity-matched patients treated at 42 centers between 2008 and 2021. Before matching, patients with a failed balloon-expandable TAV presented later after the initial procedure than those with a failed self-expanding valve. They were also less likely to be male, had more severely stenotic valves, and had less aortic regurgitation.

Overall, 55.4% of patients with a failed balloon-expandable valve received a subsequent balloon-expandable valve and 44.6% received a self-expanding device. In cases where the self-expandable TAV failed, 47.3% received a balloon-expandable valve and 52.7% another self-expandable TAV. After propensity-weighting, the mean patient age was 79.0 years, the STS risk score was 7.0%, and 56.5% of patients were male. 

We didn’t have this challenge when the therapy started, but our responsibility as operators has increased. Guilherme Attizzani

Mortality rates at 30 days were low and similar across groups. Early safety, a composite of freedom from all-cause mortality, all stroke, major bleeding, major vascular/structural complications, acute kidney injury, moderate-to-severe aortic regurgitation, new permanent pacemaker, or reintervention, was similar across all groups at 30 days. At 1 year, there was no difference in mortality between patients based on the initial and subsequent valve type.

Device success was similar regardless of the initial failed TAV type but was better if a self-expandable TAV was used for the redo procedure (77.2% with a self-expanding TAV vs 64.3% with a balloon-expandable TAV; P = 0.045). This greater procedural success was driven by better residual mean aortic valve pressures after a redo TAVI with a self-expanding TAV (10.3 vs 15.2 mm Hg with a balloon-expandable THV; P < 0.001).

Finally, in a subgroup analysis comparing the four different TAV-in-TAV combinations, the residual mean aortic gradient were: 15.7 mm Hg after balloon-expandable TAV in balloon-expandable TAV, 14.2 mm Hg after balloon-expandable TAV in self-expanding TAV, 10.7 mm Hg after self-expanding TAV in the same valve type TAV, and 10.0 mm Hg following a self-expanding TAV in the failed balloon-expandable TAV.

Some Risks of TAV-in-TAV

For Attizzani, the study shows that good outcomes can be achieved using both the self-expanding and balloon-expandable devices in failed valves. In fact, good outcomes were achieved with all of the potential combinations, although his experience also suggests that, if the anatomy is favorable, a self-expanding TAV might lead to more-favorable aortic gradients.

“The hemodynamics tend to be better,” said Attizzani. “Then again, I’ve done [redo] cases with the balloon-expandable valve inside of a self-expandable valve and it works very well. It depends on the anatomy of the patient.”

Last year, Attizzani and colleagues published their analysis of redo TAVI with the self-expanding Evolut R/PRO/PRO+ platform (Medtronic) in the TVT Registry. Short-term outcomes were also good, they reported, with device success achieved in nearly 95% of patients. At 30 days, mean gradients were 11.9 mm Hg and three-quarters of patients had no/trace aortic regurgitation. In that series, there were no cases of acute coronary occlusion. 

Comprehensive procedural planning with CT is critical for redo procedures given that there are risks to TAV-in-TAV, such as the potential for acute coronary occlusion, said Attizzani. As the second valve is implanted, the original leaflets are pinned open against the frame by the second valve, which could seal off a coronary ostium. Even in the absence of acute coronary occlusion, there is the potential that access could be limited for future coronary interventions. The present study doesn’t provide any information about the ability to access the coronary arteries after the repeat TAVI, Attizzani noted.

“It depends on the native anatomy of the patient,” said Attizzani. “The larger the anatomy—such as large sinotubular junction, large sinus of Valsalva, and high coronary takeoff—that makes our lives easier to access to the coronary arteries.”

In the current study, acute coronary obstruction occurred in two patients. Landes said that while that number is reassuring, the Redo Registry included highly selected patients deemed anatomically suitable for TAV-in-TAV. As a result, there is an inherent selection bias in the analysis. “We don’t know how many patients were denied the procedure because of an anatomical concern,” said Landes. “What we can say is that in these selected patients, the outcomes are quite reassuring and we’re probably not doing a bad job screening.”

In an editorial accompanying the paper, Neal Kleiman, MD (Houston Methodist DeBakey Heart and Vascular Center, Houston, TX), and John Carroll, MD (University of Colorado, Aurora), also point to the flaws in registry data, given the highly selected patient population. The findings highlight “key issues and imply that appropriate patient selection for redo-TAVR is possible and can yield very acceptable results,” they say, but there is still a lot more to learn.

They also point out that no device has been designed to facilitate redo TAVI, but industry is thinking about the lifetime management of TAVI patients. For example, the self-expanding Evolut FX (Medtronic), approved by the US Food and Drug Administration last year, has gold markers on the frame so that operators visualize implant depth and leaflet location during implantation.

Attizzani noted that other devices, such as the investigational Acurate neo2 (Boston Scientific), have larger cells to facilitate access to the coronary arteries.