As preference for TAVR grows, consider risks, benefits when selecting patients
Click Here to Manage Email Alerts
Procedural expertise and equipment have markedly improved since the first transcatheter aortic valve replacement procedure was performed in 2002 on an inoperable patient with severe symptomatic aortic stenosis.
Today, TAVR is becoming the procedure of choice over surgical aortic valve replacement for patients and many clinicians. Demand has continued to rise as more trial data affirm its safety and efficacy in new patient groups.
After unveiling of the PARTNER 3 and Evolut Low Risk trial data, presented at the American College of Cardiology Scientific Sessions in 2019, the expansion of TAVR to patients with severe symptomatic aortic stenosis and low surgical risk became inevitable. At the time, long-term data comparing outcomes of TAVR with surgical AVR were lacking, but 2-year results from PARTNER 3 provide a glimpse into how the two procedures compare.
“In the early days of TAVR, we were just learning how to perform the procedure, and we were looking at mortality,” Michael J. Reardon, MD, co-investigator for the Evolut Low Risk Trial, the Allison Family Distinguished Chair of Cardiovascular Research and professor of cardiovascular surgery at Houston Methodist Hospital, told Healio. “Now, we have improved to the point where we are looking to eliminate all the complications that go with this — eliminate pacemakers, eliminate stroke, eliminate bleeding. We can get people out of the hospital in 1 or 2 days and back to normal life in 1 week. People now realize this, and referring doctors and patients are coming in and asking for it.”
Healio spoke with Reardon about the impact of the low-risk studies on guidelines and practice, the growing demand for TAVR vs. selecting the best candidates, and remaining knowledge gaps in the field.
TAVR volume rising
When data from PARTNER 3 and Evolut Low Risk showed TAVR was superior to surgery in low-risk patients, the findings took many experts by surprise, given its non-inferior performance in high- and intermediate-risk patients.
In PARTNER 3, TAVR with a balloon-expandable valve (Sapien 3, Edwards Lifesciences) was superior to surgery for the primary composite endpoint of death, stroke or rehospitalization at 1 year. Similarly, in Evolut Low Risk, TAVR with a self-expanding supra-annular bioprosthesis (CoreValve Evolut R or Evolut Pro, Medtronic) was noninferior to surgery, with the estimated incidence of the primary endpoint of death or disabling stroke lower with TAVR at 2 years.
The 2020 American College of Cardiology/American Heart Association Guideline for the Management of Patients with Valvular Heart Disease reflects these new data, embracing less-invasive interventions and shared decision-making between patients and clinicians.
“Two years since presenting the low-risk data at ACC, we have seen a new set of guidelines from ACC and the AHA that no longer talks about risk,” Reardon said. “There is a class I indication for three different groups. Those aged younger than 65 years or with more than 20 years of life expectancy should undergo surgery; those aged at least 80 years or with less than 10 years life expectancy, TAVR.”
For patients who fall in the “middle” group — those aged 65 to 80 years — clinicians must balance the physiologic risk of surgery and the anatomic risk of TAVR with the patient’s desires, Reardon said.
“That is a huge change in how we look at aortic stenosis,” Reardon said. “What that means clinically is that now people are coming into my valve clinic at all ages, and they are asking for TAVR.”
In a state-of-the-art review published in the Journal of the American College of Cardiology in November 2020, researchers reported that TAVR volumes have increased every year, exceeding surgical AVR in 2019 (72,991 vs. 57,626). Since 2011, the 30-day mortality rate has decreased (7.2% to 2.5%) and stroke has started to decrease (2.75% to 2.3%), though pacemaker need has remained unchanged (10.9% to 10.8%). Alive with acceptable patient-reported outcomes was achieved in eight of 10 patients at 1 year, according to the analysis of registry data.
The volume of TAVR procedures performed in the U.S. will continue to increase, Reardon said. As more patients ask for the procedure, interventional cardiologists and surgeons must understand who was included — and who was not included — in the low-risk trials.
“These randomized trials only apply to those who were tested,” Reardon said. “That must be understood so we can make the best decisions for the lifetime management of our patients.”
Matching patient to procedure
The average age of pa rticipants in PARTNER 3 was 74 years; however, a less-invasive procedure is equally appealing to younger patients, Reardon said.
“Almost no one comes into my office now and says, ‘Would you please operate on me?’” Reardon said. “They all say, ‘Can I have a TAVR?’”
Not every patient who wants a TAVR is the ideal candidate , though, Reardon said. Particularly for patients who are younger, the clinician must weigh the risks and benefits.
“If someone comes in and is aged 62 years, then I have to sit down with them and say, ‘We will get your anatomy and see if you are even a candidate,'” Reardon said. “Then, if you are a candidate anatomically, we talk about what was not treated [in the trial], what we know and what we do not know. Then, the patient plays a part in the decision. But everyone wants TAVR, and I do not blame them.”
Interventional cardiologists and surgeons should select low-risk patients who match the participants in the low-risk trials: those with tricuspid valves, without significant coronary disease and without significant left ventricular outflow tract calcification. However, patients with significant coronary disease, those who require a concomitant procedure such as mitral valve repair or replacement or those who may be candidates for mechanical valves may not be a good fit for the procedure.
“These patients were not tested [in the trials], and we still do not know about their outcomes,” Reardon said.
With the removal of surgical risk from the equation, clinicians rely on age and life expectancy as the two biggest determinants of who is best suited for TAVR vs. surgical AVR , Reardon said.
“A normal person aged 65 years is probably going to live another 23 to 25 years; however, not all 65-year-olds are ‘normal,’” Reardon said. “If you have less than 10 years of life expectancy, you start to fall into the TAVR category.”
Clinicians should also consider factors that were not tested in the low-risk studies — among them, severe coronary disease and bicuspid valves analyzed in a randomized fashion, or mitral regurgitation that could be repaired at the same time surgically.
The ACC/AHA guideline states that the choice of type of intervention for a patient with severe aortic stenosis should be a shared decision-making process that considers the lifetime risks and benefits associated with the type of valve (mechanical vs. bioprosthetic) and type of approach (transcatheter vs. surgical).
For those who do not study the low-risk TAVR data extensively, it can be difficult to discern the nuances of the low-risk trials, such as the number of people who were rejected at the national level because of anatomy, Reardon said.
“If you look at the low-risk trials, every one of those patients was seen by their local heart team, and the local heart team signed off on whether they met the inclusion/exclusion criteria ,” Reardon said. “ They also met the anatomy for TAVR with the chosen valve, and for surgery. One would think when they got to national screening, they would all be accepted for the trials. Yet, PARTNER 3 rejected 34% of their patients, and we rejected 14.8%. It is clear this is not an all - comers , low-risk, tricuspid valve group of patients. That is important to understand.”
More to learn
Despite advances in TAVR, several key knowledge gaps remain, Reardon said.
“We still need to look at people with enlarged aortas who have not met the guideline for replacement,” Reardon said. “If we just perform a TAVR, what will happen to those people in the next 20 years? Should we have replaced them?”
Researchers are also gaining knowledge on patients with bicuspid valves, but the data remain observational and randomized studies are lacking. Researchers also lack data on people with significant coronary disease or mitral valve disease that needs to be repaired at the same time, particularly degenerative mitral valve disease, Reardon said. Still other considerations include atrial fibrillation and the possibility of performing a maze procedure and left atrial appendage occlusion at the same time.
“TAVR is a stunning advance and what goes unnoticed to most people is that, for those who started this, it was not clear at all that this was going to work,” Reardon said. “This was a very brave move on their part. Everyone looks at this now and says, ‘Of course, I would do this.’ When it started, there was huge risk for failure. For those who initiated this, kudos to them.”
References:
Carroll JD, et al. J Am Coll Cardiol. 2020;doi:10.1016/j.jac.2020.09.595.
Mack M, et al. N Engl J Med. 2019;doi:10.1056/NEJMoa1814052.
Popma JJ, et al N Engl J Med. 2019;doi:10.1056/NEJMoa1816885.
Otto CM, et al. Circulation. 2020;doi:10.1161/CIR.0000000000000923.
Collapse
Click Here to Manage Email Alerts