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:6/26/2017)... , ... June 26, 2017 , ... ... staff, and consumers are seeing lots of red these days. According to recent ... charges that result from medical coding errors(1). Some studies point to Electronic Health ...
(Date:6/25/2017)... CA (PRWEB) , ... June 25, 2017 , ... FCPX ... media into an old-fashioned vintage look. FCPX LUT Vintage Volume 2 contains 60 different ... film grain for distorted looks, vignettes and blurs to single out subjects, plus much ...
(Date:6/25/2017)... Rosa, CA (PRWEB) , ... June 25, 2017 , ... ... more green and growing foliage and plants, and along with that; a humdinger of ... sensitive allergy sufferers, it also means an increase in misery-causing grass and weed pollen. ...
(Date:6/25/2017)... ... , ... June is Men’s Health Month and the focus is on prostate cancer. ... the U.S. and the third most common cause of cancer related death today; lung cancer ... will be diagnosed with prostate cancer during his lifetime. Those at highest risk ...
(Date:6/24/2017)... (PRWEB) , ... June 24, 2017 , ... ... Dental365 family. Located at 217 Portion Road in Lake Ronkonkoma, Dental365 offers patients ... and weekends so that visits to the dentist fit into their patients’ busy ...
Breaking Medicine News(10 mins):
(Date:6/5/2017)... The Cincinnati location of ... (NYSE: DPLO), has been awarded a Top Workplaces 2017 ... Results are based on an employee survey administered by WorkplaceDynamics, ... improvement. The survey measures several aspects of workplace culture, including ... ...
(Date:6/3/2017)... , June 3, 2017  Eli Lilly ... announced that results from the Phase 3 MONARCH ... (CDK)4 & 6 inhibitor, in combination with fulvestrant, ... with fulvestrant alone in women with hormone-receptor-positive (HR+), ... breast cancer who have relapsed or progressed after ...
(Date:6/1/2017)... , June 1, 2017 Nutriceutical Holdings (NH), ... Recommended Solutions (VRS), and KD Pharma Group have decided ... Holdings by KD Pharma Group. KD Pharma Group will ... option to acquire the entire company. "We ... They are committed to growing the NH companies by ...
Breaking Medicine Technology: