GAINESVILLE,
Fla. – For patients who have
severe narrowing of the aortic valve, a condition known as aortic stenosis,
standard treatment is surgical replacement of the damaged valve. But advanced
age or medical problems such as lung disease prevent many of those patients
from having open chest surgery. In the past, the best such patients could hope
for was to control their symptoms with medications.
Now they can live longer thanks to a new minimally invasive
treatment that involves inserting an artificial valve that takes over the work
of the diseased valve. The University
of Florida is among a
limited number of facilities around the country initially approved to offer the
procedure.
“Its exciting – this technology opens an option for
patients who otherwise do not have a repair option,” said cardiologist Anthony
A. Bavry, M.D., M.P.H., an assistant professor in the UF College of Medicines
department of medicine. “Previously we had to treat these patients with
medications, and unfortunately many did not do well. This is a big change.”
The new valve replacement technique, called transcatheter
aortic valve replacement, or TAVR, was approved by the U.S. Food and Drug
Administration in November 2011. Medical practices approved to perform the
procedure had to demonstrate high levels of expertise and collaboration in
cardiology and surgery, as well as high-quality facilities for conducting the
procedure and collecting data for patient care and monitoring.
Bavry and R. David Anderson, M.D., M.S., director of
interventional cardiology at UF, will team with thoracic and cardiovascular
surgeons Thomas M. Beaver, M.D., M.P.H., and Charles T. Klodell, M.D., to do
the procedure at UF&Shands, the University of Florida Academic Health
Center. Working in such multidisciplinary teams streamlines and speeds patient
evaluation and decisions about the best course of action.
“You have both a surgeon and a cardiologist seeing a
patient, reviewing the data and making the best decision about how to treat,”
Bavry said.
Among the elderly, severe aortic stenosis is the most common
abnormality of the heart valves. But up to one-third of such patients are
considered ineligible for surgery. They are instead given medicines to control
heart rate and blood pressure, and their heart volume is monitored in order to
head off congestive heart failure. Medical treatments ease symptoms but do not
prolong life.
In the new TAVR procedure, the artificial valve – framed by
a stent and wrapped around a balloon – is transported up to the aortic valve
via a large catheter in the leg. The new valve is then anchored into position
inside the diseased valve by inflation of the balloon. Placement of the stent
is monitored with X-ray and ultrasound imaging.
Patients survival chances improve with the new technique.
In clinical trials involving 700 patients, treatment with the new procedure cut
the death rate nearly in half after one year of having the implanted device,
compared with medical therapy alone.
“This is one of the best things that has happened in the
last 10 years in interventional cardiology,” said Samir Kapadia, M.D., an
interventional cardiologist at the Cleveland Clinic who is one of the leaders
in clinical trials of the new technique. “Procedurally, its like a miracle –
patients are sick, you do the critical part of the valve replacement in 15 to
30 seconds and all of a sudden the heart starts working more efficiently. It
has changed the way we do things and has provided treatment options for lots of
people who did not have an option before.”
The procedure has also been compared with traditional open
surgery in patients who were operable but had a high risk of dying if they did
have surgery. After a year, patient outcomes were comparable to those of
surgery patients. Additional studies are being carried out to see how the
procedure works among patients who are at lower risk of death if they have
surgery.
The UF team has begun evaluating patients to see who might
be good candidates for the procedure. Tests include chest CT scans, cardiac
catheterization and EKGs. They are also reaching out to physicians whose
patients might benefit.
Research continues on new ways to insert the valve, as well
as on new types of valves, including one that can be repositioned after it has
been placed inside the body.
Posted by Sean Fenske, Editor-in-Chief, MDT
