What researchers from the low-risk TAVR trial anticipate they will find in their decade-long assessment.
At the American College of Cardiology (ACC) 2019 Annual Scientific Session in New Orleans, LA, Michael J. Reardon, MD, presented data transcatheter aortic valve replacement (TAVR) in severe aortic stenosis patients with a low risk of death from surgery is a potentially significantly greater options for care than surgery itself.
The two-year TAVR data is promising, but long-term assessment may be more affirmative. In an interview with MD Magazine®, Reardon, a professor of Cardiothoracic Surgery and Allison Chair of Cardiovascular Research at Houston Methodist Hospital, mapped out a ten-year assessment under the Bayesian analysis. Their findings could better dictate prescribing specialists.
MD Mag: What is the clinical significance in assessing TAVR for two-year outcomes?
Reardon: Well this trial will be followed for 10 years, and so we're going to get some really good data. We chose a two-year endpoint of all-cause mortality or disabling stroke because it's a low-risk-population, and we thought we needed to choose very objective measurements. Death and disabling stroke, they’re objective. You can't be subjective, and this is basically an open-label trial. You know what you got, you know if you had TAVR or surgery.
So, hospitalizations can be more subjective. Now, the other trial used hospitalizations, but their data was so good it doesn't really matter. They beat them in all levels, just like we beat him in all levels. And so we didn't use hospitalization. We used 2 years because we wanted what we thought was a stronger endpoint for the lowest population.
We used Bayesian analysis because it allows us to get our data out earlier, and bring this therapy to patients who really need it. Now quality of life, in every single trial that we've run—randomized against surgery—quality of life improves faster at 1 month in TAVR than does surgery. But by 6 months, they're both have large improvements in quality of life, and it's equal. And it stayed equal across the spectrum that we follow to at least 5 years.
What are the goals in assessing for even further long-term outcomes?
The best hope for outcomes is that the survival of TAVR across 10 years is as good as or better than surgery. And we hope that the quality of life remains as good as or better, which I think that's going to be true, and that these valves are durable.
One of the things we worry about with biologic valves, even surgical biologic valves, is they can wear out over time. And the older you are when we put them in, the faster you die, because you're already older, and the longer the valves last.
So there's a switchover place where we start using biologic valves, and for most surgeons that's somewhere between 60 and 65 years of age. Between 50 and 60, if I talk about mechanical valves versus biologic, the survival is the same. It's a risk of anticoagulation bleeding for the mechanical valve, and the risk of deterioration and having a re-do procedure for the biologic valve—which used to be re-do a valve replacement. Now it's transcatheter valve.
So if a patient comes to me and they're a candidate for a biologic valve, I think I really need to have a conversation with them about what's out there. We have data out to 6 and 7 years now in these valves, and the durability seems to be absolutely as good as surgery.