Featured Research

from universities, journals, and other organizations

Commonly prescribed PAH medications could have adverse effects

Date:
January 17, 2013
Source:
University of Alberta Faculty of Medicine & Dentistry
Summary:
Scientists have reported findings that significantly improve understanding of how widely used drugs in Pulmonary Arterial Hypertension affect the heart health of treated patients.

A research team with the Faculty of Medicine & Dentistry at the University of Alberta reported findings that significantly improve understanding of how widely used drugs in Pulmonary Arterial Hypertension (PAH) affect the heart health of treated patients.

Related Articles


The research shows that medications often prescribed for PAH could block the function of an important hormone in the heart, decreasing the strength of contraction of the right heart chambers, a potentially important and yet unrecognized adverse effect.

PAH is a disease that affects the blood vessels of the lungs, causing a progressive narrowing and restriction of the blood flow through the lungs. This narrowing puts a significant strain in the right chamber (right ventricle) of the heart that pushes the blood through the lungs. Eventually the right ventricle fails, causing heart failure and death.

One of the causes of the narrowing of the lung blood vessels is the increased levels of endothelin in the lungs, a hormone that constricts blood vessels throughout the body. Commonly used and very expensive drugs that block the actions of endothelin, which are called endothelin receptor antagonists, or ERAs, are now used throughout the world to treat PAH patients. However, the effects of these drugs in the right ventricle had not previously been studied, until now.

Led by cardiologist Evangelos Michelakis and cardiac surgeon Jayan Nagendran's in a laboratory setting, a multidisciplinary team of cardiologists, cardiac surgeons, pathologists and scientists at the U of A studied human hearts from 50 PAH patients and laboratory models. The team showed that, while in the normal hearts, ERAs do not have significant effects because the endothelin levels are quite low, this is not the case in the diseased hearts of PAH patients. In the thickened right ventricles from PAH patients, the levels of endothelin are significantly increased.

This new finding suggests that this increase may be beneficial for hearts impacted by PAH, since endothelin is known to increase the strength of contraction of the heart muscle. In other words, as the right ventricle has to work harder pushing blood through the narrowed blood vessels, endothelin may help it function better, but this may be blocked by ERAs. The research team also showed that, as expected, ERAs decrease the strength of contraction of the diseased right ventricles.

"These new findings -- that ERAs have direct effects on the right chambers of the heart -- have important implications for treated patients" said Nagendran. "For example, PAH patients treated with ERAs can develop fluid retention (swelling), which is currently treated with diuretics. As fluid retention can be a result of decreased right ventricle function, the new findings suggest that this could be a previously unrecognized important adverse effect of these drugs."

In other words, while ERAs may have a beneficial effect on the lung blood vessels, they may also have unwanted effects on the heart.

"While this does not mean that PAH patients should stop using these drugs, this new research sheds more light on the overall mechanism of action of these drugs in PAH patients," said Michelakis. "It may also help physicians to better approach the treatment of PAH patients and design clinical studies to validate these new findings in large populations."

PAH tends to mostly affect younger women, although both sexes of all ages can be affected. The survival of PAH patients is similar to that of patients with metastatic breast cancer, but the yearly cost of treatment can be more than double compared to that of metastatic breast cancer, and can exceed $200,000 per patient.


Story Source:

The above story is based on materials provided by University of Alberta Faculty of Medicine & Dentistry. Note: Materials may be edited for content and length.


Cite This Page:

University of Alberta Faculty of Medicine & Dentistry. "Commonly prescribed PAH medications could have adverse effects." ScienceDaily. ScienceDaily, 17 January 2013. <www.sciencedaily.com/releases/2013/01/130117133330.htm>.
University of Alberta Faculty of Medicine & Dentistry. (2013, January 17). Commonly prescribed PAH medications could have adverse effects. ScienceDaily. Retrieved October 24, 2014 from www.sciencedaily.com/releases/2013/01/130117133330.htm
University of Alberta Faculty of Medicine & Dentistry. "Commonly prescribed PAH medications could have adverse effects." ScienceDaily. www.sciencedaily.com/releases/2013/01/130117133330.htm (accessed October 24, 2014).

Share This



More Health & Medicine News

Friday, October 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

IKEA Desk Converts From Standing to Sitting With One Button

IKEA Desk Converts From Standing to Sitting With One Button

Buzz60 (Oct. 24, 2014) IKEA is out with a new convertible desk that can convert from a sitting desk to a standing one with just the push of a button. Jen Markham explains. Video provided by Buzz60
Powered by NewsLook.com
Ebola Protective Suits Being Made in China

Ebola Protective Suits Being Made in China

AFP (Oct. 24, 2014) A factory in China is busy making Ebola protective suits for healthcare workers and others fighting the spread of the virus. Duration: 00:38 Video provided by AFP
Powered by NewsLook.com
WHO: Millions of Ebola Vaccine Doses by 2015

WHO: Millions of Ebola Vaccine Doses by 2015

AP (Oct. 24, 2014) The World Health Organization said on Friday that millions of doses of two experimental Ebola vaccines could be ready for use in 2015 and five more experimental vaccines would start being tested in March. (Oct. 24) Video provided by AP
Powered by NewsLook.com
Doctor in NYC Quarantined With Ebola

Doctor in NYC Quarantined With Ebola

AP (Oct. 24, 2014) An emergency room doctor who recently returned to the city after treating Ebola patients in West Africa has tested positive for the virus. He's quarantined in a hospital. (Oct. 24) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins