ViV TAVR Bests Redo Surgery for Failed Valves: Retrospective Study

For patients with a failed biological aortic prosthesis, a valve-in-valve (ViV) TAVR procedure is associated with lower early mortality, lower morbidity, and shorter hospital stay as well as increased survival compared with redo surgery, according to a new propensity-matched analysis.

Prior studies in this space have generally been small and have shown no difference in early and late mortality. Even so, rates of redo surgery have been on the decline.

“Overall, these findings suggest that the less invasive approach with ViV TAVR reduces upfront mortality and morbidity leading to improved late survival,” write lead author Derrick Tam, MD (Sunnybrook Health Sciences Centre, Toronto, Canada), and colleagues.

Speaking with TCTMD, senior author Stephen Fremes, MD (Sunnybrook Health Sciences Centre), said the results “certainly” support ViV TAVR for patients older than 70 years, while those younger than 60 would likely still be candidates for redo surgery. “For patients in their 60s, a heart team decision is probably most appropriate to determine what the optimal form of treatment for that individual should be,” he added.

For the study, published online today ahead of print in JACC: Cardiovascular Interventions, the researchers linked clinical and administrative databases in Ontario, Canada, to evaluate outcomes following redo SAVR (n = 344) and ViV TAVR (n = 214) in 131 propensity-matched pairs over a period of approximately 10 years. The ViV TAVR patients were older and had more comorbidities compared to those who underwent redo surgery.

In the matched analysis, ViV TAVR was associated with lower absolute risks of early mortality (-7.5%), permanent pacemaker implantation (-9.8%), and blood transfusion (-63.1%) as well as shorter length of stay (7 vs 14 days) over redo surgery.

Over a median follow-up period of 3.2 years, 5-year survival in the matched analysis was higher with ViV TAVR than with redo surgery (76.8% vs 66.8%; HR 0.55; 95% CI 0.30-0.99). However, there were no differences in all-cause readmission or freedom from MACCE at 5 years.

In the unmatched analysis, the early and late outcomes findings were similar, but ViV TAVR was associated with higher late all-cause readmission than redo surgery.

Choosing the Right Patients

“Patient selection remains key in the treatment of biological aortic valve prosthesis failure,” the authors write. “Indeed, certain anatomic and patient characteristics may drive the decision regarding approach.”

Both bioprosthetic valve fracture as well as the BASILICA laceration technique have emerged as novel strategies to assist in this field and “will likely expand the eligible pool of patients with failed biological prothesis for ViV TAVR,” they note.

Commenting for TCTMD, Amar Krishnaswamy, MD (Cleveland Clinic, OH), who was not involved in the study, said his institution employs bioprosthetic valve fracture routinely for “almost all” of their ViV TAVR cases. “We believe it provides the optimal hemodynamic result for patients moving forward,” he said. “Similarly, it’s important to consider whether coronary obstruction either at the time of the index valve-in-valve procedure, or if we’re thinking about a future valve-in-valve procedure, whether BASILICA may be necessary at either of those times. It’s important that operators are facile with some of those techniques.”

The patient’s overall valve life journey is something that is an important topic of conversation at all the major meetings nowadays, specifically to address these kinds of issues. Amar Krishnaswamy

Krishnaswamy agreed with Fremes that ViV TAVR should be the first choice for patients over 70 years, but said “the question about whether younger patents should have a valve-in-valve TAVR I think in large part centers on the size of the TAVR valve that we can place. If we’re able to place a very large TAVR valve, even for a younger patient, that could be a reasonable strategy because they would simply have more room in their aortic annulus for future valve-in-valve. On the other hand, for a younger patient with an already small surgical valve, putting in one valve-in-valve may not really be that helpful because they might be looking at a redo cardiac surgery further down the road.”

Occasionally, he noted, patients in their 50s and 60s opt for ViV TAVR over surgery due to family and lifestyle reasons. “The patient’s overall valve life journey is something that is an important topic of conversation at all the major meetings nowadays, specifically to address these kinds of issues,” Krishnaswamy said.

No ‘Panacea’ Yet

Noting the recent approval of TAVR for use in low-risk patients with severe aortic stenosis, Stefan Stortecky, MD, and Daniel Malebranche, MD (both Bern University Hospital, Switzerland), write in an accompanying editorial that “the TAVR landscape is rapidly expanding and indications will change in the near future.” Because of this, they estimate “ViV TAVR will likely expand not only in SAVR patients with failed bioprosthetic valves but also in TAVR patients with structural valvular deterioration.”

Stortecky and Malebranche point to several limitations of the study, “including the potential influence of unmeasurable confounders and treatment allocation bias.” Also, propensity matching was not possible for about 30% of the ViV patients, and “this may have served to create a relatively selected patient population and a biased view when interpreting the results of this study,” they add.

Even so, the study findings “corroborate the results of other reports in the literature and consistently show that ViV TAVR is associated with favorable outcomes,” the editorialists write. “This may pave the way for future studies evaluating the potential factors contributing to improved outcomes such as augmented aortic valve areas, reduced gradients across the aortic valve and higher rates of LV mass regression. Furthermore, as the number of TAVR platforms continues to increase, it will also be interesting to evaluate additional data on the impact of annular versus supra-annular TAVR devices on ViV TAVR procedures.”

In the meantime, Fremes said, operators are “going to continue treating patients before we actually know whether what is the right thing to do.” It’s likely that ViV TAVR will “become a better option as there is device improvement and also as there is procedural improvement in those who are not so well suited for valve-in-valve at the moment [as well as] some changes in the surgically implanted valves to make them more TAVR-friendly,” he continued, adding that his team has been running models to try and simulate best options.

Going forward, Krishnaswamy said, it will “be really important to understand whether there's any difference in valve durability when it’s applied in the valve-in-valve setting versus the native aortic valve setting, and there are certain different considerations about flow stasis and flow dynamics in the aortic root that may imply differences in durability though we don’t really have any understanding of that yet.”

The question remains as to how many times a valve-in-valve procedure can be performed, he added. “Will we be able to place a valve sort of indefinitely, or like a Russian nesting doll situation? [Or] because of the scarring that develops in the valve leaflets, will we be unable to do more than one more valve or more than two more valves? I think that’s specifically germane if we're talking about applying the valve-in-valve therapy in younger patients.”

“While the panacea for failed bioprosthetic valves (both surgical and TAVR) may not yet be here, this could still be the beginning of an exciting new paradigm in repeat aortic valvular intervention,” conclude Stortecky and Malebranche.