Navigation Links
Cold air chills heart's oxygen supply
Date:2/28/2012

People with heart disease may not be able to compensate for their bodies' higher demand for oxygen when inhaling cold air, according to Penn State researchers, making snow shoveling and other activities dangerous for some.

"This study can help us understand why cold air is such a trigger for coronary events," said Lawrence I. Sinoway, Distinguished Professor of Medicine and director of the Heart and Vascular Institute, Penn State College of Medicine.

Breathing cold air during exercise can cause uneven oxygen distribution throughout the heart. But a healthy body generally corrects for this problem and redistributes blood flow, making sure the heart continues to function properly. In people with heart problems -- such as coronary artery disease -- this may not be the case, said Sinoway.

"If you are doing some type of isometric work and you're breathing cold air, your heart is doing more work -- it's consuming more oxygen," said Sinoway, also director of the Clinical and Translational Science Institute at Penn State.

Isometric work includes such activities as shoveling snow and carrying a briefcase or laptop bag. The heart works harder when exerted in cold temperatures and the number of deaths due to cardiac arrest peaks during the winter.

"There are two different things going on here -- demand and supply," said Matthew D. Muller, postdoctoral fellow at the Heart and Vascular Institute, Penn State College of Medicine. "We thought that oxygen demand in the heart would be higher with cold-air breathing and we also thought that oxygen supply would be a little bit impaired. And that's generally what we found."

Sinoway, Muller and colleagues reported their results in a recent issue of the Journal of Applied Physiology and in the current issue of the American Journal of Physiology, Heart and Circulatory Physiology.

The researchers first studied healthy young adults in their 20s and then studied a group of healthy older adults in their 60s so that they could learn how the heart functions in people without disease. Each subject was monitored for lung function and heart functions during the trials.

In order to measure heart function during exercise, the participants performed an isometric, or static, handgrip, which is a maneuver known to increase blood pressure. Subjects squeezed the handgrip device and held it still for two minutes, providing a consistent workload on the heart for the researchers to measure. Muller and Sinoway found that there was a supply-demand mismatch in the left ventricle -- where the heart receives oxygenated blood -- yet the heart was able to continue functioning appropriately.

These findings "suggest that healthy humans can adequately redistribute blood to the subendocardium (the blood vessels entering the heart) during the combined stimulus of cold-air inhalation and handgrip exercise," the researchers stated.


'/>"/>

Contact: Victoria M. Indivero
vmi1@psu.edu
814-865-9481
Penn State
Source:Eurekalert

Related medicine news :

1. “Hearts and Minds” Education Program Launched: On Average, People with Mental illness Live 25 Years Less than Other Americans
2. Hearts of Hospice Patients Being Needlessly Shocked
3. Healing Wounds and Hearts: Warrior Weekend Helps Soldiers and Marines Relax and Recover
4. Researchers discover chemical that may protect hearts of muscular dystrophy patients
5. Hearts and Minds Promotes Wellness; African Americans Living with Mental Illness Have Higher Risk for Other Illnesses.
6. Tiny Fish Might Help Humans Fix Damaged Hearts
7. Mans Best Friend Helps Mend Broken Hearts
8. Stem cells from surgery leftovers could repair damaged hearts
9. High-Stress Jobs Tax Womens Hearts, Too
10. 2 BigHearts Board Announces Addition to Board of Directors: Michael Unetich
11. Hostile, Competitive Types May Be Harming Their Hearts
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/29/2016)... ... 2016 , ... Since launching its annual volunteer campaign on ... footwear industry, has broken all previous participation records in its first two weeks ... during the months of April and May, the 2016 Footwear Cares initiative is ...
(Date:4/29/2016)... ... April 29, 2016 , ... Our bodies are bombarded daily by ... and deal with these stressors is to adopt a more healthful diet, but too ... Risa Groux, a certified Holistic Nutritionist and the creator of the Newport Beach Cleanse ...
(Date:4/29/2016)... CA (PRWEB) , ... April 29, 2016 , ... ... advocating optimistic healthcare awareness and author of best seller "LOVE, MEDICINE and MIRACLES") ... Radio Monday, May 2, 2016 and podcasted thereafter . Dr. Bernie Siegel, ...
(Date:4/29/2016)... Fort Stewart, GA (PRWEB) , ... April 29, 2016 , ... ... on Monday, May 16, 2016, at its new location in the Exchange Furniture Mall ... including a raffle for a 50-inch Samsung Smart TV. Plus attendees will have the ...
(Date:4/29/2016)... ... April 29, 2016 , ... ... team BioCellection won the $30,000 Perlman Grand Prize of the 2016 Wharton Business ... Award, the Michelson People’s Choice Award, and the Committee Award for Most ‘Wow ...
Breaking Medicine News(10 mins):
(Date:4/27/2016)... Schweiz, April 27, 2016 ... CEO Forums in Zürich gab Strekin AG ... Wirkstoffkandidaten STR001 zur Erhaltung des Resthörvermögens von ... bekannt. Für die umfassende Phase-II-Doppelblindstudie mit Placebo-Kontrollgruppe ... angeworben. STR001 wird während der Operation direkt ...
(Date:4/27/2016)... , April 27, 2016   Zillion ... its digital health technology platform, which specializes in ... programs into scalable digital products, Zillion enables companies ... and empower consumers to take control of their ... live video conferencing – including one-to-one, group and ...
(Date:4/27/2016)... 2016 Oasmia Pharmaceutical AB ... a new generation of drugs within human and ... for Paclical/Apealea in the Phase III study that ... ovarian cancer. These preliminary results showed non-inferiority between ... carboplatin versus Taxol in combination with carboplatin. In ...
Breaking Medicine Technology: