Mitral Valve Replacement/Repair:


Mitral valve prolapse is a heart
problem in which the valve that
separates the upper and lower
chambers of the left side of the heart
does not close properly.


MITRAL VALVE REPAIR       
The heart has four chambers. Each
time the heart contracts (beats), the
chambers on the right send
deoxygenated blood from the body
back to the lungs. The left chambers
pump oxygenated blood to the body.
One-way valves in the heart keep
blood flowing in one direction.

The mitral valve controls the flow of
blood between the upper and lower
chambers on the left side of the heart.
It has two flaps. When the heart beats,
the mitral valve opens to allow the
upper chambers to push blood into the
lower chambers. As the ventricles
contract to push blood to the body, the
flaps on the mitral valve close,
preventing blood from the lower
chamber from leaking back into the
upper chamber.

Sometimes the flaps on the mitral valve
don’t seal properly. Sometimes the
valve flaps are thick or abnormally
large. In any case, the flaps are unable
to form a tight seal, allowing some
blood to leak back into the upper
chamber (called regurgitation).

Most people with mitral valve prolapse
don’t have any problems because the
leakage is minimal. If the leakage is
more significant, patients may have
shortness of breath, fatigue,
palpitations, lack of energy and
swelling of the ankles. In serious
cases, the backward flow of blood can
put a strain on the heart because it
has to work harder to get blood to the
body. This can cause the heart muscle
to increase in size and lead to high
blood pressure in the lungs and
development of an irregular heart beat
(arrhythmia).

In the past, doctors used to replace a
leaky or diseased mitral valve with a
mechanical (man-made) or a biological
(from a human cadaver, pig or cow)
valve. Now, many physicians prefer to
repair the valve rather than replace it.
Mitral valve repair is associated with a
lower risk for mortality, better heart
function, reduced risk for stroke.

Traditionally, mitral valve repair has
been done using a large incision in the
chest and breaking the chest bone to
access the heart. Today, select
physicians are using a minimally
invasive approach, making a two- to
three-inch incision. James Gammie, M.
D., Cardiothoracic Surgeon with the
University of Maryland Medical Center
in Baltimore, says for women, the
incision is typically made under the bra
line. Once the surgeon has access to
the heart, the repair procedure is the
same as in open surgery.

The minimally invasive surgery
patients spend three to four days in
the hospital (versus four to five days
for open surgery patients). Most are
back to work within a week or two.

Gammie says minimally invasive mitral
valve repair is not a very common
procedure. Patients needing surgery
should look for a physician who has a
great deal of experience in the
procedure.

MONARC by Edward Life Sciences:
replacing heart valves with keyhole
surgery in trial EVOLUTION II;


MITRA CLIP TO REPLACE OPEN
HEART SURGERY FOR VALVE
REPAIR
MitraClip, from Abbott Laboratories,not
yet approved by the Food and Drug
Administration. If approved, the device
would enable surgeons to repair leaky
heart valves without the need for full-
blown open heart surgery. They could
do it through two tiny keyholes instead.

The MitraClip is inserted with a
catheter through a leg vessel to
correct mitral regurgitation, which
occurs when the mitral valve doesn’t
close properly causing blood to flow
backward. The condition, which can
lead to heart failure, affects more than
8 million people in the U.S. and
Europe. The defect is currently
managed with drugs or repaired with
surgery.

For decades, patients with severe
mitral regurgitation underwent a
procedure called the double orifice
technique, in which a surgeon sews
together two sides of the mitral valve,
leaving the ends open and ensuring
blood flows in the proper direction. The
MitraClip procedure mimics that
surgery without the intensive
operation, inserting the clip through a
catheter in the leg and clamping the
two sides of the valve shut.

The trial, dubbed Everest II, was
designed to see whether the MitraClip
would be safer than open-heart
surgery and “non- inferior” in terms of
effectiveness.

The device met the study’s goal for
effectiveness.


VALVE-IN-VALVE  PROCEDURE
REPLACES FAILING ANIMAL-BASED
HEART VALVES

Replacing failing artificial animal-based
heart valves by implanting mechanical
valves inside them is an effective
option for high-risk patients, according
to research reported in Circulation:
Journal of the American Heart
Association. In the study, physicians
from Canada and the United Kingdom
describe how 24 high-risk patients
whose previous implants failed
received transcatheter valve-in-valve
implantation, where a new artificial
valve is seated within a previously
implanted valve made of pig or cow
tissue.
The new valve is inserted on a
catheter through a small incision
between the ribs or through a puncture
in a blood vessel in the leg. Placed
inside the old surgically implanted
valve and expanded by inflating a
balloon, the new valve pushes the old
one out of the way.

Once expanded and opened, the new
valve opens and functions similarly to
the patient's own valve. The
advantage is that failing surgical
valves can be replaced without the
need for open-heart surgery.
Many, but not all, surgical valves can
be replaced this way.

The procedure is offered only to
selected patients with failed surgical
valves who would be poor candidates
for another operation.