I am Dr. Raj Makkar
from Cedars-Sinai medical center in Los Angeles.
Well, transcatheter aortic valve replacement
has become a very acceptable treatment
for patients with aortic stenosis
based on pivotal randomized clinical trials
that have been done in the last decade.
But, however, these trials excluded
bicuspid aortic stenosis anatomy.
So in young patients, as we, you know
are treating more and more younger patients,
almost 50% of these patients have bicuspid anatomy.
It is therefore imperative that we have more data on the use
of TAVR in patients with bicuspid aortic stenosis.
In the United States, all transcatheter aortic valve
replacement procedures are registered in a registry,
it's called the SDS ACC TVT registry.
So, this data set essentially provides us
an opportunity to look at all patients with TAVR,
including patients who had bicuspid aortic stenosis
and an event transcatheter aortic valve replacement.
So, between 2015 and 2020,
there were almost 150,000 patients
that underwent transcatheter aortic valve replacement
with the balloon expandable SAPIEN 3
or SAPIEN 3 ultra valve.
And of these, more than 30,000 patients
actually very low risk for surgery.
Our primary goal here was to see what are the outcomes
of transcatheter aortic valve replacement
in patients who have bicuspid aortic stenosis
and who are low risk for surgery.
So, essentially in the entire dataset, there were more than
7,000 patients with bicuspid aortic stenosis,
and more than 3,200 patients actually
were bicuspid aortic stenosis and were low risk for surgery.
We looked at the outcomes of TAVR in these patients
and we compared them to the outcomes
of patients with tricuspid aortic stenosis
by performing what is called a propensity
one-to-one matching.
What we found was that in these low-risk patients
where the average age was less than 69 years,
both for bicuspid and tricuspid aortic stenosis,
the STS was 1.7,
which means that the expected mortality was 1.7% at 30 days.
When TAVR was performed,
the outcomes were actually quite good.
The intra-procedural outcomes were good
in hospital mortality in patients
with tricuspid aortic stenosis was 0.6% compared to 0.4%.
You know, in patients who had tricuspid aortic stenosis,
similarly the stroke rates were around one or 1.2%
in both bicuspid and tricuspid aortic stenosis.
So, similar outcomes, in terms of death and stroke,
were also seen at 30 days and one year.
So at 30 days, the mortality
from TAVR or mortality in patients who had undergone TAVR
with bicuspid aortic stenosis was 0.9%.
So this is pretty good.
This is, you know, comparing it to patients
with tricuspid aortic stenosis
and comparing it to the published literature
with surgery, with bicuspid aortic stenosis,
our conclusion was that at 30 days,
these outcomes are quite competitive.
In addition, they're looking at the mortality
and stroke rates at one year.
Once again, what we found was that the mortality
with bicuspid aortic stenosis at one year was about 4%.
And similarly with tricuspid aortic stenosis
it was about 6%.
So, our conclusion is that these end points
of death and stroke are similar between
bicuspid and tricuspid aortic stenosis in patients
who are at low-risk for surgery.
The intra-procedural outcomes, including conversion
to open heart surgery were very low in these patients.
Similarly, the rates of re-intervention
after bicuspid aortic stenosis were also quite low,
you know, after TAVR.
We also looked at the echocardiographic outcomes,
which is the gradients and the valve areas
and there were similar.
We also looked at the functional measures
which is quality of life, you know,
in terms of the improvement in KCCQ scores
and the improvement in NYHA class.
And they were quite impressive and similar between bicuspid
and tricuspid aortic stenosis, indeed,
at one year almost 95% of the patients
that had undergone TAVR for bicuspid aortic stenosis
were in NYHA class one or class two.
So, I would deduce that,
based on these results, we feel that,
you know, in selected patients,
the TAVR is actually a very reasonable
alternative to surgery in patients with bicuspid anatomy.
So, the way TAVR is performed
in the United States is with a heart team approach.
Specific anatomical characteristics when
not collected in the TVT registry,
and we do know that morphology can play an important role
in the outcomes of TAVR after bicuspid aortic stenosis.
So that, in a way, is somewhat of a limitation of the study.
But nonetheless, what can be said is that
if the heart team decides, after evaluating clinical aspects
of the patient and the imaging characteristics of a patient,
at least in the United States,
in this consecutive series of patients,
when TAVR was performed
the outcomes were actually quite good.
I think we need to gather more data,
precisely to guide what anatomical characteristics
should dictate the patient undergo TAVR versus surgery.
We have performed one such study,
but I think we need to do further work in that area.
And finally, I do believe that it would be ideal
to do a randomized clinical trial
between surgery and transcatheter aortic valve
in patients who have bicuspid aortic stenosis
and who are at low risk for surgery.