Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Beta-blockers may help broader group of patients with heart problems

09.03.2005


Researchers find drugs boost survival in those with congestive heart failure and mitral regurgitation with normal ejection fraction



Beta-blockers, medications that block the action of certain hormones on the heart, can benefit patients with certain serious heart problems such as diastolic heart failure, according to cardiologists at the Keck School of Medicine of the University of Southern California and Loma Linda University Medical Center.

Researchers presented two reports on the use of beta-blockers in patients with chronic severe mitral regurgitation, or MR, and congestive heart failure, CHF, at the American College of Cardiology’s 54th Annual Scientific Session on March 7. These patients had a normal ejection fraction, a measure of how well the heart pumps out blood. "Our findings are encouraging because there are no data on the survival benefit of medical therapy in CHF or severe MR patients with normal ejection fraction. CHF with normal ejection fraction, popularly referred to as diastolic heart failure, makes up nearly 50 percent of all CHF patients-and these patients have very similar mortality and morbidity as those with reduced ejection fraction," says Padmini Varadarajan, M.D., advanced cardiac imaging fellow in the Department of Cardiovascular Medicine at the Keck School of Medicine and the study’s lead author.


In their first presentation, researchers showed that using beta-blockers as part of therapy significantly reduced risk of death for patients with chronic severe mitral regurgitation with normal ejection fraction. The mitral valve separates the heart’s left atrium from the left ventricle. With every heartbeat, oxygen-rich blood moves from the left atrium, a holding chamber, to the left ventricle, which squeezes or ejects the blood out to the rest of the body. When the mitral valve does not close well, blood can flow from the ventricle back into the atrium-a condition called mitral regurgitation. That means blood flow to the rest of the body decreases, and the heart may have to work extra hard to compensate.

Doctors can see how well the left ventricle works by measuring the ejection fraction, which is the percentage of blood squeezed out of the ventricle with each heartbeat. An ejection fraction of 50 percent means the ventricle spurts out half its volume each time it contracts. Healthy ejection fractions are 50 percent or higher; lower ejection fractions can mean heart disease. But patients may have normal ejection fractions and still have serious heart problems such as severe mitral regurgitation.

In the study, 32 percent of 869 participating mitral regurgitation patients were on a beta-blocker. Beta-blockers reduce the heart rate and the force of muscle contraction, thereby reducing oxygen demand on heart muscle. The researchers found that beta-blockers increased patients’ survival, independent of patients’ age, gender, or whether they had coronary artery disease, diabetes, high blood pressure or valve surgery. In a related poster, researchers showed the drugs’ benefits to patients with diastolic heart failure-those with congestive heart failure, or CHF, who have normal ejection fraction.

Researchers studied 2,246 patients with CHF; 1,079 of them had normal ejection fractions. The patients were on a variety of CHF therapy regimens, which might include aspirin, diuretics, digoxin, ACE inhibitors and beta-blockers.

Beta-blockers were once thought risky for heart-failure patients. But the investigators found that after five years, 65 percent of patients treated with beta-blockers were alive, compared to 50 percent of those who received no beta-blockers. Beta-blocker therapy still showed a strong survival benefit after researchers adjusted for patients’ age, gender, hypertension, diabetes and coronary artery disease.

Ramdas G. Pai, M.D., professor of clinical cardiovascular medicine at the Keck School and the study’s senior author, explained that catecholamines-the hormones released in the body in stress situations such as heart failure and mitral regurgitation-are toxic to the heart muscle. Beta-blockers keep catecholamines from acting. "For the first time, our large observational studies show that beta-blockers may have large benefit in CHF and severe MR patients with normal ejection fraction. However these findings need to be substantiated further by randomized clinical trials," she says. She and her colleagues are planning further study on the drugs.

Sarah Huoh | EurekAlert!
Further information:
http://www.usc.edu

More articles from Health and Medicine:

nachricht Researchers release the brakes on the immune system
18.10.2017 | Rheinische Friedrich-Wilhelms-Universität Bonn

nachricht Norovirus evades immune system by hiding out in rare gut cells
12.10.2017 | University of Pennsylvania School of Medicine

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Osaka university researchers make the slipperiest surfaces adhesive

18.10.2017 | Materials Sciences

Space radiation won't stop NASA's human exploration

18.10.2017 | Physics and Astronomy

Los Alamos researchers and supercomputers help interpret the latest LIGO findings

18.10.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>