I'm David Cohen.
I'm a interventional and structural cardiologist.
I work at the Cardiovascular Research Foundation
in New York city and practised at St. Francis Hospital
on Long Island.
(bright intro music)
So the study that I presented at the TCT
was the economic study of the partner three,
randomised trial.
The importance of this study is that
transcatheter aortic valve replacement, TAVR,
as we call it here in the United States
is becoming increasingly popular.
If there are more TAVRs done in the United States
than surgical valve replacements now,
but the valve is quite expensive.
In the United States,
the TAVR valve costs about $32,000
and surgical valves costs between five and $6,000.
So there's quite a large price differential,
and there's always been concern
with the high cost of the TAVR valve,
whether it's economically feasible
from the standpoint of the healthcare system.
And so our study was really designed
to address whether TAVR
compared with surgical aortic valve replacement
is cost-effective for these large group
of low-risk patients.
The data that we used for this study
were came directly from the partner three, randomised trial.
We actually linked the patients in the randomised trial
to Medicare data,
which is available for the vast majority of those patients
because of their age,
and through the Medicare data,
we were able to obtain their in-hospital costs
as well as their follow-up costs
for all of their medical care,
including physician visits, outpatient care,
hospitalizations, rehabilitation,
all of those factors over a two year follow-up period.
The factors that come into play in comparing these costs
really are all of the differences and different patterns
of resource utilisation.
In the initial hospitalisation,
TAVR is a much quicker procedure
with a much shorter hospitalisation.
And then we were interested in understanding
of whether there were additional costs savings
during the follow-up period,
perhaps related to a reduction in rehospitalizations
or on the contrary, of whether there was catch-up,
whether the less invasive nature of TAVR
and some of the complications
that are a little more frequent with TAVR
such as paravalvular regurgitation or pacemakers
led to higher costs in the follow-up period.
In addition, we wanted to understand
the quality of life of these patients,
which was done through patient surveys
that were conducted at different time intervals
over the follow-up period.
So the key findings of our study were several,
first, the procedures were much more expensive
for the TAVR patients by about $19,000.
This was obviously driven by the high cost
of the TAVR valve.
During the remainder of the hospitalisation though,
TAVR led to about four and a half day shorter hospital stays
including about two days shortening of ICU stay.
And that was associated with substantial cost savings.
By the time the patients left the hospital,
the costs were almost identical,
only about $500 higher with TAVR.
Then over the next two years,
there were another $2,600 worth of cost savings with TAVR
and this related mostly to reductions in rehabilitation
and rehospitalization costs that occurred
during the first six months of follow-up.
Finally, there were small
but important improvements in both survival
or life expectancy,
as well as quality of life
in the early follow-up time period,
leading to a gain of about 0.05 quality adjusted life years
with TAVR compared with surgical aortic valve replacement.
When the cost and the quality adjusted life expectancy data
were combined,
TAVR was an economically dominant strategy.
That is, it saved money and improved outcomes for patients
compared with surgical aortic valve replacement
over the two year follow-up period.
The cost-effectiveness ratio
was highly cost-effective at a threshold of $50,000
per quality adjusted year of life gained.
And 95% of replicates indicating
that we are very highly confident
that at least at two year follow-up,
TAVR is highly cost-effective
compared with surgical aortic valve replacement.
These results also extend to lifetime perspective,
but only if one assumes
that there are no major differences in survival
between the two strategies at that time,
which at the present, you know,
currently is not completely certain.
We did a number of subgroup analysis
and there were two groups that really stood out
in terms of cost-effectiveness.
One was patients who had
New York Heart Association class three or four symptoms
when they presented for their valve replacement,
and the other was patients
who had a Kansas City Cardiomyopathy Questionnaire score
of less than or equal to 70.
These are both really saying the same thing,
which is that patients who had more symptoms
and more disability,
more functional limitations when they presented
were more likely to derive a substantial economic benefit.
In those two patient groups,
the cost savings at two year follow-up
were not just $2,000
as they were in the overall population,
but actually between six and $7,000 per patient.
So those two groups really stood out
as being the most cost-effective uses of TAVR
compared with surgical valve replacement.
The take home messages from this study are that at least
over the two-year intermediate term follow-up period,
TAVR is an economically dominant strategy
for these low-risk patients
with severe symptomatic aortic stenosis,
saving money, as well as improving quality of life,
and actually providing a small gain in life expectancy
for these patients.
However, the lifetime cost effectiveness of TAVR
is still very dependent on the long-term outcomes.
If there is a modest survival benefit
with surgical aortic valve replacement,
then these findings would actually reverse
and surgical aortic valve replacement
would become much more cost-effective,
but that is an area of great uncertainty,
and we need to wait for the five
and 10 year follow-up of the trial
in order to understand those findings.
So the next steps are, first of all, to publish our results.
So we're in the process of writing them up
so people will be able to read them
and understand them in great detail.
And then second, most importantly,
to continue to follow the same patients, which is ongoing.
There will be trial follow-up at five years
and the sponsor and the FDA are continuing the follow-up
through 10 years now,
to really understand the long-term outcomes,
whether there are differences in valve durability,
whether there are differences in quality of life,
and whether there are differences in survival
as these patients continue to live
with their prosthetic valves.
(bright music)