Researchers Continue Search for Drug to Treat
Seniors for Emerging Form of Heart Failure
Blood pressure drug AvaproTM fails against common
problem for older people, particularly women - diastolic heart failure
Dec. 4, 2008 A medication used for high blood
pressure AvaproTM - does not improve a common form of heart failure,
diastolic heart failure, according to new results from a large, international study. The findings
are disappointing, according to the researchers, who continue to search
for a successful treatment for the condition, which predominantly
affects older people, particularly women.
Thiazolidinediones medications (including rosiglitazone
(Avandia)
produced a significantly increased risk of heart attack, congestive
heart failure and death
The study, which included researchers at Wake
Forest University Baptist Medical Center in key leadership positions,
appears in this week's issue of the New England Journal of Medicine,
published today.
"Heart failure is the only cardiovascular disease
on the rise," said Dalane Kitzman, M.D., a cardiologist and professor in
the Department of Internal Medicine at Wake Forest Baptist, principal
investigator for the Wake Forest Baptist trial site and the national
coordinator for the study.
"And this newer form of the disease is increasing
fastest of all. That's what makes it disconcerting that we don't have
a proven effective treatment. We sort of have to go back to the drawing
board."
Doctors long believed that most heart failure was
caused by a weakening of the heart muscle that kept it from pumping
enough blood out to the body (systolic heart failure). In recent years,
however, they have recognized a second and more common form of the
disorder in which the heart can empty normally, but does not fill with
enough blood (diastolic heart failure).
The result is the same the body does not get
enough oxygen-rich blood for its needs. The most common symptom is
shortness of breath. Other symptoms include fatigue, swelling around the
ankles and high blood pressure.
Few drugs have been tested as treatment strategies
in randomized studies of patients with diastolic heart failure largely
because the condition wasn't recognized as a separate form of heart
failure until the past decade. To date, no effective treatments have
been found.
Wake Forest Baptist researchers and colleagues,
both internationally and within the United States, altogether recruited
4,128 patients with the condition from 25 countries. The patients, all
of whom were at least 60 years old, were randomly placed into two
groups.
One group received 300 milligrams of irbesartan, an
anti-hypertensive medication marketed as AvaproTM.
The other group was given a placebo.
Doctors tracked the patients for five years,
documenting their progress and outcomes.
The study showed treatment with irbesartan did not
reduce the risk of death or hospitalization for cardiovascular causes
among patients who had diastolic heart failure, nor did it improve any
of the secondary clinical outcomes, including quality of life.
Researchers chose irbesartan for the study because
previous, smaller studies in humans with diastolic heart failure
indicated that the drug may have had a potential benefit, Kitzman said.
While irbesartan was not successful in treating
diastolic heart failure, the study showed the medication, though
powerful, was found to be safe for patients with the condition, he said.
There were fewer bad outcomes than predicted,
Kitzman added. This may have been partly because blood pressure was well
controlled from the start of the study by design. While the results were
not positive, Kitzman said, the study does provide helpful clues to
treatment of the disease. "If you have the disease but can control blood
pressure with medication, the patient is likely to do pretty well," he
said.
New Trial Seeks Participants
Because the disease is so common, researchers are
continuing work to find effective treatments. Kitzman and colleagues at
Wake Forest Baptist are collaborating in another ongoing trial called
TOPCAT (Treatment of Preserved Cardiac function heart failure with an
Aldosterone anTagonist), testing another medication for treatment of
this condition. The study is being funded by the National Institutes of
Health. Patients interested in participating can contact (336) 713-4702.
Background Information
Authors of the irbesartan study were Barry M.
Massie, M.D., University of California, San Francisco; Peter E. Carson,
M.D., Georgetown University and the Veterans Affairs Medical Center,
Washington, D.C.; John J. McMurray, M.D., British Heart Foundation
Glasgow Cardiovascular Research Centre; Michel Komojda, M.D., Universitι
Paris 6 and Hospital Pitiι-Salpκtriθre; Robert McKelvie, M.D., Hamilton
Health Sciences, McMaster University, Canada; Michael R. Zile, M.D.,
Ralph H. Johnson Veterans Affairs Medical Center and Medical University
of South Carolina, Charleston; Susan Anderson, M.S., and Erik Iverson,
M.S., University of Wisconsin, Madison; Mark Donovan, Ph.D., and Agata
Ptaszynska, M.D., Bristol-Myers Squibb; and Christoph Staiger, M.D.,
Sanofi-Aventis.
The study was funded by pharmaceutical companies
Bristol-Myers Squibb and Sanofi-Aventis.
Wake Forest University Baptist Medical Center (www.wfubmc.edu)
is an academic health system comprised of North Carolina Baptist
Hospital, Brenner Children's Hospital, Wake Forest University
Physicians, and Wake Forest University Health Sciences, which operates
the university's School of Medicine and Piedmont Triad Research Park.
About Heart Diseases
Also called: Cardiac disease
If you're like most
people, you think that heart disease is a problem for other
folks. But heart disease is the number one killer in the U.S. It
is also a major cause of disability.
There are many
different forms of heart disease.
The most common
cause of heart disease is narrowing or blockage of the coronary
arteries, the blood vessels that supply blood to the heart
itself. This is called
coronary
artery disease and happens slowly over time. It's the
major reason people have
heart
attacks.
Other kinds of heart problems may happen
to the
valves
in the heart, or the heart may not pump well and cause
heart
failure. Some people are
born
with heart disease.
You can help reduce your risk of heart
disease by taking steps to control factors that put you at
greater risk:
● Control your
blood
pressure
● Lower your
cholesterol
● Don't smoke
● Get enough exercise
Heart failure is a condition in which the
heart can't pump enough blood throughout the body. Heart failure
does not mean that your heart has stopped or is about to stop
working. It means that your heart is not able to pump blood the
way it should.
The weakening of the heart's pumping
ability causes
● Blood and fluid to back up into the lungs
● The buildup of fluid in the feet, ankles and legs - called
edema
● Tiredness and shortness of breath
Each year over a million people in the
U.S. have a heart attack. About half of them die. Many people
have permanent heart damage or die because they don't get help
immediately. It's important to know the symptoms of a heart
attack and call 9-1-1 if someone is having them.
Those symptoms include
● Chest discomfort - pressure, squeezing, or pain
● Shortness of breath
● Discomfort in the upper body - arms, shoulder, neck, back
● Nausea, vomiting, dizziness, lightheadedness, sweating
These symptoms can sometimes be different
in
women.
What exactly is a heart attack? Most
heart attacks happen when a clot in the coronary artery blocks
the supply of blood and oxygen to the heart. Often this leads to
an irregular heartbeat called an
arrhythmia - that causes a severe decrease in the pumping
function of the heart. A blockage that is not treated within a
few hours causes the affected heart muscle to die.
Dec. 4, 2008 A medication used for high blood
pressure AvaproTM - does not improve a common form of heart failure,
diastolic heart failure, according to new results from a large, international study. The findings
are disappointing, according to the researchers, who continue to search
for a successful treatment for the condition, which predominantly
affects older people, particularly women.