Acute Decompensated Aortic Stenosis: Time for an Urgent TAVI Pathway?

LONDON, England—Patients identified as having acute decompensated aortic stenosis (ADAS) during their index hospitalization do best if their TAVI procedures are done as soon as possible, a single-center study suggests.

Longer hospitalizations in these patients were independently associated with adverse outcomes, said Michael Mc Kenna, MD (Barts Health NHS Trust, London, England), who presented the retrospective analysis here at PCR London Valves 2023.

The findings lend support to TAVI programs that are evolving different triage processes based on patients’ presentation and represent a key departure from surgical approaches, which have emphasized stabilization before intervention.

“Expediting TAVI in ADAS patients may result in significantly lower rates of heart failure hospitalizations, cardiovascular mortality, and all-cause mortality over medium-term follow-up,” Mc Kenna said. Based on these observational data, his hospital has piloted an urgent care pathway for TAVI in ADAS, known as ASTRID-AS (Assessment and Treatment of Decompensated Aortic Stenosis), which he likened to acute MI and acute stroke programs. “Time to TAVI is potentially a modifiable risk factor in patients with ADAS,” he said.

Mc Kenna estimated that up to one-third of aortic valve replacements entail patients who present with ADAS, with this subgroup facing a higher risk of prolonged hospitalizations, acute kidney injury, and long-term mortality. Mc Kenna and his colleagues became interested in these patients because they don’t always have overt heart failure (HF) symptoms; they may have preserved ejection fraction, yet they present with very advanced AS, he said. Current practice, however, can lead to unnecessary delays—his own center does not have an emergency department, so patients are already arriving a few days into their acute decompensation. And their transfer typically happens after the patient has been stabilized and sent for cardiac imaging, which might be staggered over days or weeks. Moreover, patients found to have asymptomatic AS are typically managed with a watch-and-wait strategy.

“Based on previous studies, people had always assumed there was an element of time,” said Mc Kenna. “There's always this kind of paradigm of people thinking that, with asymptomatic severe aortic stenosis, you can just leave them basically untreated in terms of interventional treatment until they develop symptoms, or until the echocardiographic parameters become so severe. . . . We've lived with [that paradigm] for so long and I think maybe that's the difference between aortic stenosis and other kinds of more urgent conditions.”

Prior studies of patients with aortic stenosis and cardiogenic shock have supported a role for urgent balloon angioplasty versus a wait-to-stabilize approach, he noted. The aim of this study was to take that one step further with an urgent TAVI pathway.

Time to TAVI

The analysis included all patients with ADAS undergoing urgent TAVI during their index hospitalization, excluding any patients who had a prior ADAS diagnosis. Patients were then stratified according to whether their time to TAVI was shorter or longer than the median delay.

As Mc Kenna showed here, 276 patients were admitted with ADAS, with a median time to TAVI of 22 days (ranging from 12 to 32 days). Procedural complications, he noted, were no different according to time to TAVI, mean ejection fraction at admission was 55%, and follow-up was a mean of 3.1 years.

Overall rates of HF hospitalization/all-cause mortality were 58% for these ADAS patients following TAVI, while rates of HF hospitalization/CV mortality were 35%.

When patients were stratified, however, according to whether they waited more than 22 days to TAVI, or 22 days or less, those with shorter delays had significantly lower rates of all-cause death or HF hospitalization out to 4 years. When patients were further stratified by quartile of delay to TAVI, those in the lowest quartile—less than 13 days—were significantly less likely to die or be hospitalized.

“Oftentimes we think it seems sensible that we should medically stabilize someone and have them kind of optimized before we go into urgent TAVI, but it's a question of whether or not those kinds of assumptions actually are reflected in clinical practice,” Mc Kenna told TCTMD. “We're conscious of the fact that this is one center, it's a retrospective cohort study, but I suppose it does raise the question of whether we should be taking that as gospel or whether we should be exploring this more.”

Different Waiting Lists

Commenting on the study for TCTMD, Guillaume Bonnet, MD, PhD (Cardiovascular Research Foundation, New York, NY, and University Hospital of Bordeaux, France), who presented two cases of emergency TAVI procedures here at the meeting, said other centers are also rethinking the approach to unstable AS patients.

While he is not convinced that ADAS patients make up one-third of the TAVI population, he said the subset is not insignificant, and warrants attention. “I think there is a shift in the pathway of aortic stenosis care,” he said. In the early days of transcatheter aortic valve interventions, procedures were typically planned weeks in advance. Now, triage protocols and advanced training allow for more-rapid identification, workup, and imaging of patients who need TAVI not within weeks, but within hours or days. “Now, for many reasons, there is clearly a place to do some procedures in an emergency fashion,” Bonnet said.

This break from the stabilize-first approach, pioneered by surgeons, speaks to a growing evidence base supporting the leveraging of less-invasive procedures to be used emergently, not just for aortic stenosis, but also mitral regurgitation, Bonnet added. In his own case-based presentations at PCR London Valves, Bonnet made the case for “Shock Heart” teams made up of the surgeon, interventionalist, anesthesiologist, and ICU cardiologist who are on call at any given time and who can make quick decisions as to whether a decompensated AS patient needs urgent transcatheter repair.

Such teams, he stressed, need to share the same mindset regarding the benefits and rationale for treating these patients emergently, and be available on call for weekend or after-hours consultation, just as is done for acute MI. Rather than disrupting waiting lists, he said, hospitals may want to think of these kinds of aortic stenosis patients according to entirely different pathways of care—two different waiting lists.

Patrick W. Serruys, MD, PhD (University of Galway, Ireland), commenting on the data following Mc Kenna’s presentation, said the study carried an “important message.” It’s long been assumed that patients should be “compensated” before heading to aortic valve replacement, sometimes even getting sent home from the hospital and then brought back. This small, single-center study implies that presumption needs a second look, he said.