Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Some heart patients vulnerable to mental stress


Anxiety restricts blood flow in some patients

The fear of public speaking might cause some people to do more than just break out in a cold sweat and battle stomach-churning butterflies - it could prove to have consequences for their heart health.

University of Florida cardiologists have identified a group of heart disease patients who appear especially vulnerable to the physical effects of mental stress.

Chronic anxiety, depression or anger are widely recognized as raising the risk of heart attack, hospitalization or sudden death in patients whose hearts suffer dangerous decreases in blood flow during exercise testing. Even something as simple as public speaking, doing mental arithmetic or recounting an argument with a loved one can trigger a problem.

But until now, patients who trod the treadmill without experiencing chest pain or restricted blood flow had never been similarly scrutinized when it came to mental stress. Yet what goes on in their heads could have consequences for their hearts as well, UF researchers write in today’s (March 7) issue of the Journal of the American College of Cardiology. A third of the heart patients they studied developed temporary changes in heart rhythm or restricted blood flow when they were asked to role-play a difficult interpersonal situation, even though their hearts responded normally to exercise.

"Recently our group and some other investigators have started to expand the population of patients that we’re looking at to try to explore what happens when mental stress is applied," said David S. Sheps, M.D., a professor and associate chairman of cardiovascular medicine at UF’s College of Medicine and the Malcom Randall Veterans Affairs Medical Center. "We believe the phenomenon of mental stress-induced reductions in blood flow to the heart is much more common than has been previously recognized."

In general, studies have shown that as many as two-thirds of patients with coronary artery disease who experience exercise-related reductions in blood flow to the heart respond similarly to mental stress. These bouts often produce no symptoms of chest pain and are rarely detectable on a standard electrocardiogram. Yet last year UF researchers found that these patients have a threefold greater risk of dying - as large a risk factor as cigarette smoking or high cholesterol. Other studies have linked stress experienced after mass disasters or natural catastrophes with a rise in heart attacks and sudden death.

Psychological stress can leave the heart more prone to developing arrhythmias or electrical instability and the blood more prone to clotting. Stress appears to raise heart rate and rapidly hike blood pressure, increasing the heart’s need for oxygen-rich blood, Sheps said. Yet less oxygen is supplied, in part because coronary arteries constrict, impeding blood flow. Doctors are concerned that this reaction to stress in the laboratory is simply a snapshot of how patients respond to the stress of life day in and day out.

In the current study, funded by the National Institutes of Health and Bristol-Myers Squibb, UF researchers studied 21 men and women with documented heart disease who had no signs of reduced blood flow during exercise on the standard exercise treadmill test or on nuclear perfusion scans of the heart. Participants were given two minutes to prepare to deliver a four-minute speech about a hypothetical stressful situation. Blood pressure and electrocardiographic measurements were taken every minute during the speech and for 10 minutes afterward. About half an hour after the speech, participants underwent heart imaging scans that reflected blood flow to the heart during the stressful situation.

"These are patients who for example might have had a severe lesion or a narrowing of one of the coronary arteries and may have had a stent inserted; they’re tested after that and found to have no decreased blood flow with the standard type of exercise testing," Sheps said. "However, we found that about 30 percent of them had evidence of decreased blood flow with the mental stressor."

In general, 20 percent to 30 percent of all patients cardiologists see could respond in a similar fashion, Sheps estimated. Simply warning patients to avoid stress because it’s bad for them is not enough, he added.

"All of us are leading more and more stressful lives, and it’s hard to avoid it," he said. "We as physicians need to find better ways to treat this phenomenon to avoid having patients develop this type of response to an increased stressor."

UF researchers are now conducting a related study involving more than 300 patients. They are interested in replicating the findings and determining whether these patients are more likely to suffer a heart attack, be hospitalized or die from cardiac complications, Sheps added.

Why does mental stress restrict blood flow in some patients even when exercise fails to have the same effect? The effects of mental stress could predominantly affect the heart’s smaller vessels, causing them to spasm and temporarily limiting blood flow, he speculated. In contrast, exercise tends to affect the heart’s larger vessels.

The findings suggest patients who experience reductions in blood flow detectable when they are experiencing mental stress but not during standard exercise radionuclide testing may have a worse form of heart disease than expected, cautioned David S. Krantz, Ph.D., chairman and a professor of medical and clinical psychology at the Uniformed Services University in Bethesda, Md.

"This patient group warrants further study since they may have functionally more severe coronary artery disease," he said.

Melanie Fridl Ross | EurekAlert!
Further information:

More articles from Health and Medicine:

nachricht NIH scientists describe potential antibody treatment for multidrug-resistant K. pneumoniae
14.03.2018 | NIH/National Institute of Allergy and Infectious Diseases

nachricht Researchers identify key step in viral replication
13.03.2018 | University of Pittsburgh Schools of the Health Sciences

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: Researchers at Fraunhofer monitor re-entry of Chinese space station Tiangong-1

In just a few weeks from now, the Chinese space station Tiangong-1 will re-enter the Earth's atmosphere where it will to a large extent burn up. It is possible that some debris will reach the Earth's surface. Tiangong-1 is orbiting the Earth uncontrolled at a speed of approx. 29,000 km/h.Currently the prognosis relating to the time of impact currently lies within a window of several days. The scientists at Fraunhofer FHR have already been monitoring Tiangong-1 for a number of weeks with their TIRA system, one of the most powerful space observation radars in the world, with a view to supporting the German Space Situational Awareness Center and the ESA with their re-entry forecasts.

Following the loss of radio contact with Tiangong-1 in 2016 and due to the low orbital height, it is now inevitable that the Chinese space station will...

Im Focus: Alliance „OLED Licht Forum“ – Key partner for OLED lighting solutions

Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, provider of research and development services for OLED lighting solutions, announces the founding of the “OLED Licht Forum” and presents latest OLED design and lighting solutions during light+building, from March 18th – 23rd, 2018 in Frankfurt a.M./Germany, at booth no. F91 in Hall 4.0.

They are united in their passion for OLED (organic light emitting diodes) lighting with all of its unique facets and application possibilities. Thus experts in...

Im Focus: Mars' oceans formed early, possibly aided by massive volcanic eruptions

Oceans formed before Tharsis and evolved together, shaping climate history of Mars

A new scenario seeking to explain how Mars' putative oceans came and went over the last 4 billion years implies that the oceans formed several hundred million...

Im Focus: Tiny implants for cells are functional in vivo

For the first time, an interdisciplinary team from the University of Basel has succeeded in integrating artificial organelles into the cells of live zebrafish embryos. This innovative approach using artificial organelles as cellular implants offers new potential in treating a range of diseases, as the authors report in an article published in Nature Communications.

In the cells of higher organisms, organelles such as the nucleus or mitochondria perform a range of complex functions necessary for life. In the networks of...

Im Focus: Locomotion control with photopigments

Researchers from Göttingen University discover additional function of opsins

Animal photoreceptors capture light with photopigments. Researchers from the University of Göttingen have now discovered that these photopigments fulfill an...

All Focus news of the innovation-report >>>



Industry & Economy
Event News

Virtual reality conference comes to Reutlingen

19.03.2018 | Event News

Ultrafast Wireless and Chip Design at the DATE Conference in Dresden

16.03.2018 | Event News

International Tinnitus Conference of the Tinnitus Research Initiative in Regensburg

13.03.2018 | Event News

Latest News

TRAPPIST-1 planets provide clues to the nature of habitable worlds

21.03.2018 | Physics and Astronomy

The search for dark matter widens

21.03.2018 | Materials Sciences

Natural enemies reduce pesticide use

21.03.2018 | Life Sciences

Science & Research
Overview of more VideoLinks >>>