Stress May Be Tougher on Women's Hearts
Than Men's: Study
Preliminary research found blood flow doesn't rise in women,
possibly raising their cardiac risk.
Heart blood flow increases
in men when they experience mental stress, but does not change in women, a
small new study suggests. The finding may explain why women are more likely
than men to have heart trouble when they suffer emotional distress, the Penn
State College of Medicine researchers said.
The investigators measured
heart rate, blood pressure and heart blood flow in 17 healthy adults -- a
near-equal mix of men and women -- at rest and while they did three minutes of
mental arithmetic. In order to increase the stress of doing the math task, the
researchers urged the participants to hurry up or informed them they were wrong
even when they gave the right answer.
At rest, men and women
showed little difference in heart rate, blood pressure and heart blood flow.
During the math task, all the participants had increases in heart rate and
blood pressure. Heart blood flow also increased in men during the stressful
task, but did not change in women.
The study was slated for
Tuesday presentation at the Experimental Biology meeting, in San Diego.
The findings suggest that
women may be more susceptible to heart problems while under stress and could
explain why women tend to have more heart troubles after stressful events, such
as losing a spouse, study leader Chester Ray said.
The results also underscore
how mental stress can affect health.
"Stress reduction is
important for anyone, regardless of gender, but this study shines a light on
how stress differently affects the hearts of women, potentially putting them at
greater risk of a coronary event," Ray said in an American Physiological
Society news release.
He added that further
research on the mechanism behind this difference between women and men could
someday lead to more targeted treatments and prevention efforts for women at
risk of coronary artery disease.
Because this study was
presented at a medical meeting, the data and conclusions should be viewed as
preliminary until published in a peer-reviewed journal.
(SOURCE: American Physiological Society, news
release, April 24, 2012)
Study Explores Fish Oil's Healthy Effect
on Heart
Researchers rule out one possible explanation.
A small new study may rule
out one possible mechanism behind omega-3 fatty acids' healthy effects on the
heart.
It's been established that
omega-3 fatty acids, found in foods such as fish oil, help prevent
cardiovascular disease (conditions of the heart and blood vessels), as well as
heart attacks and strokes in people who already have cardiovascular disease.
The evidence is so strong
that the American Heart Association recommends eating fish or taking fish oil
as a preventive measure both for healthy people and cardiovascular-disease
patients.
The ways in which omega-3
fatty acids provide these heart-healthy benefits, however, aren't known.
In the new study,
researchers from the Penn State College of Medicine investigated if omega-3s
might improve cardiac diastolic function -- the ability of the heart to relax
and refill with blood at each beat. This ability declines with age.
The researchers used
echocardiograms to assess heart structure and function in 11 healthy men and
women with an average age 66 at the start of the study. The participants took
daily omega-3 supplements for 12 weeks, and then had another echocardiogram.
The results showed that
taking the omega-3 supplements did not change diastolic function in the
participants. This suggests that the benefits of omega-3 fatty acids may occur
in other areas of heart function, the researchers said.
The findings, scheduled for
presentation Tuesday at the Experimental Biology 2012 meeting in San Diego,
should not discourage people from taking fish oil or other omega-3 supplements
for heart health, researcher Kevin Monahan said in a Federation of American
Societies for Experimental Biology news release.
"I don't think there's
any reason to stop taking fish oil based on our data," he said in the
release. "From a big-picture standpoint, we know that consumption of fish
and fish oil reduces cardiac disease risk and mortality. Just because omega-3
supplements don't improve diastolic function over 12 weeks in this population
doesn't mean that these nutrients don't exert other important cardiac
effects."
Pacemakers, Defibrillators Sources of
Deadly Infections: Study
As implanted heart devices increase, so do serious
complications, research says.
Life-saving implantable
pacemakers or defibrillators pose a risk for developing deadly infections, a
new study suggests.
More than 4.2 million
people in the United States had a permanent pacemaker or defibrillator
implanted between 1993 and 2008, and heart-device infections increased 210
percent during that time, according to the study.
"These infections tend
to occur in very vulnerable patients who have other medical conditions that may
partially contribute to developing an infection," said study author Dr.
Andrew Wang, a cardiologist at Duke University Hospital in Durham, N.C.
Pacemakers help control
abnormal heart rhythms. Defibrillators use shocks to help manage
life-threatening heart-rhythm abnormalities that can cause sudden cardiac
death.
The findings appear in the
April 25 issue of the Journal of the American Medical Association.
Heart-device-related
infections, which are caused by bacteria, grow more dangerous when they spread
to the heart valve or other organs. Treating these infections requires
prolonged antibiotic therapy, removal of the device and possibly device
reimplantation, but repeat surgeries also can be risky. Hospital charges for
this complication are at least $146,000, the authors said.
Researchers set out to
determine how common and lethal these infections are, and which heart patients
are at greatest risk. Using data from 61 centers in 28 countries, they found
that of 2,760 people with an infection of the heart's lining or valves
(endocarditis), an implantable heart device was the cause in 177 cases.
Endocarditis carries an
increased risk of death compared to other heart-device-related infections.
Overall, device-related
infections were more common in older men, who were about 71 on average. The
infection reached the heart valve in 66 people in the study. Other
complications included heart failure and persistent blood infections.
Factors such as longer
hospital stays and medical procedures unrelated to the implantable device also
increase the likelihood of infection. Health-care-associated infection was seen
in 81 of the patients with an implantable cardiac device, the study showed.
Device removal sometimes
carries more risks than benefits. "It comes down to a decision as to
whether the device infection can be cleared without having to remove it,"
Wang said. "In general, most experts feel removing the device is
necessary."
Infections are more likely
to be fatal when the valve is involved, but those people who have the infected
device removed at the time of the initial infection do live longer, the study
showed.
Preventing these infections
is a challenge, Wang said. Knowing the signs and symptoms can help identify
device infections early. There may be skin inflammation if it is an infection
of the pacemaker leads or wires. There also are systemic signs of infection,
including low-grade fever, weight loss and night sweats. Earlier detection
lowers risk of infection spreading to a valve, but some strains of bacteria are
stealthier than others, he said.
This risk is "real and
sobering," said Dr. Gregory Crooke, a cardiac surgeon at Maimonides
Medical Center in New York City. "It is not insignificant. Catch it as
early as possible and intervene as early as possible."
Hardware removal is
preferable to antibiotics, Crooke said.
"Removal of the
infected device is simpler than open heart surgery, which is what will be
needed if the infection spreads to the valve," he said.
Crooke said prevention
starts when the device is first implanted. Doctors need to take all precautions
to make sure it is done in a sterile and hygienic environment.
Dr. Ranjit Suri, director
of the Electrophysiology Service and Cardiac Arrhythmia Center at Lenox Hill
Hospital in New York City, agreed. "We should do everything in our power
to prevent these infections starting with using pristine sterile
techniques," he said.
"We should try and
limit our exposure to pathogens in the hospital by prevention techniques,
including hand washing and shortening a patient's stay in the hospital,"
Suri said. "The longer they stay in the hospital, the higher their risk of
infection."
If a patient does develop
an infection, "there is clearly a survival advantage with removal of the
whole system," Suri added. "Antibiotics themselves won't sterilize
the infection."
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