Cardiac Pathways 101
Fundamental Causes for Cardiac Disease - Articles
- IR - responsible for 42% of all heart attacks
BP for Nitrates
Dietary nitrate decreased blood pressure in obstructive sleep apnoea syndrome: a series of N-of-1 trials. https://www.ncbi.nlm.nih.gov/pubmed/26934033
Fat, Not Calcium, Is Heart Attack Culprit
Monday February 26 5:44 PM ET By Suzanne Rostler
NEW YORK (Reuters Health) - Patients whose arteries are clogged with fatty
plaque may be more susceptible to heart attack than those whose arteries
are coated with calcium-containing plaque, researchers report.
The findings indicate that treatments aimed at reducing the build-up of
cholesterol in the arteries may be more useful than drugs that seek to
reduce amounts of plaque that contain calcium deposits.
The study also
highlights the importance of developing new methods for
identifying the most unstable lesions in patients before they rupture,''
such as technologies that can detect the fat content, Dr. Richard T. Lee
from Brigham and Women's Hospital and Harvard Medical School (news - web
sites) in Boston, Massachusetts, and the study's lead author said in an
interview.Currently, this isn't easy to do, but several methods like
magnetic resonance imaging or catheter-based techniques are promising,''
Fatty plaque can be more dangerous than calcium-containing plaque because
it is more likely to rupture and cause the formation of blood clots, which
can cause heart attack and stroke, the researchers explain.
Lee likened the production of artery-clogging lesions to a bench with
supports at each end and in the middle.
If you replaced the support in
the middle with another hard support like calcium, the bench will still be
stable. But if you replaced it with a soft material like lipid (fat), it
would be much less likely to support a heavy person,'' he said.
While calcification may suggest a more extensive form of heart disease, it
appears to be less likely to lead to heart attack, according to the report
published in the February 27th issue of Circulation: Journal of the
American Heart Association (news - web sites).
The researchers examined the composition of artery plaque in 20 cadavers.
Half of lesions were ruptured at the time of death. Fatty plaque appeared
to cause more stress on artery lesions and was up to 25% less stable than
calcified plaque, the report indicates.Our results demonstrate that within a typical lesion, the presence of
lesion lipid (fat) is much more important...than calcium,'' the study
SOURCE: Circulation 2001;103.
Infections Linked to Clogged Arteries
SOURCE: Circulation 2001;103:1064-1070. February 26 5:26 PM ET
By Merritt McKinney
NEW YORK (Reuters Health) - Common, chronic bacterial infections,
including lung and urinary tract infections, as well as gum disease, may
increase the risk of atherosclerosis, a build-up of fatty plaques in the
arteries that could lead to heart attack, study findings suggest.
During the 5-year study, people with chronic bacterial infections were
nearly three times more likely to develop new plaques in carotid arteries,
which are the large arteries in the neck that deliver blood to the brain.
A build-up of fat in the neck arteries can increase the risk of stroke,
and is a sign that heart arteries may be clogged as well.
Our study provides strong evidence that chronic infection is a risk
factor (for) atherosclerotic vascular disease,'' the study's lead author,
Dr. Stefan Kiechl, of the University of Innsbruck in Austria, told Reuters
Health.These data may offer new clues (about) future disease
But Kiechl cautioned that widespread use of antibiotics to fight chronic
infections--and hopefully prevent atherosclerosis--is not justified. Such
an approach must first be tested for safety and effectiveness in clinical
trials, some of which are already under way, he said. In the meantime, he
recommended taking steps to reduce the risk of developing chronic
infections, including improving oral health, eating a healthy diet and not
Previous research has suggested a link between infections and heart
attacks, but few studies have examined the relationship between infections
and atherosclerosis, which can lead to heart attack and stroke, Kiechl and
his colleagues note in a report in the February 27th issue of Circulation:
Journal of the American Heart Association (news - web sites).
The current study included 826 white men and women aged 40 to 79 years who
were followed from 1990 to 1995. Participants underwent ultrasound
scanning of their carotid arteries at the beginning and end of the study.
Chronic infections were present in 268 of the participants. Infections
were more common in heavy smokers and drinkers, older people and
individuals of low socioeconomic status.
During the study, 41% of participants developed new plaques in their
carotid arteries, the researchers report. People who had chronic
infections were 2.78 times more likely to develop new plaques than people
who did not have any infections.
But not all infections were linked to an increased risk of
atherosclerosis. The study found that only bacterial infections, not
infections caused by viruses like cytomegalovirus, the herpes zoster virus
or hepatitis B or C, increased the risk of artery disease.
Kiechl and his colleagues suspect that infection-related inflammation may
play a role in the increased risk. Patients with infections who had high
levels of inflammation tended to have a greater risk of atherosclerosis,
they report. Another possible explanation, according to the authors, is
that bacterial infections may trigger the immune system to turn against
itself. This so-called autoimmune response may damage vessels, making it
easier for fatty deposits to accumulate, they note.
Fatty Acids Up Sudden Death Risk in Healthy Men
Monday August 13 5:34 PM ET
By Suzanne Rostler
NEW YORK (Reuters Health) - Healthy middle-aged men who have elevated
blood levels of
free'' fatty acids may be 70% more likely to experience
sudden cardiac death than their peers with lower levels of the compounds,
French researchers report.
It is known that high levels of fatty acids in the blood--orfree''
fatty acids--can trigger irregular heartbeats, leading to sudden death in
people with heart disease. These compounds now appear to be just as
dangerous for those who have not been diagnosed with heart disease,
according to the report in the August 14th issue of Circulation: Journal
of the American Heart Association (news - web sites).
Researchers led by Dr. Xavier Jouven, of the University of Paris, tracked
the 22-year medical histories of over 5,200 healthy men aged 42 to 53
years. The study authors believe their findings underscore the importance
of reducing heart disease risk factors among all middle-aged men--not just
those with diagnosed heart disease.
The prevention of sudden death is first the prevention of cardiovascular
disease: to quit smoking, balance cholesterol levels and treat high blood
pressure,'' Jouven told Reuters Health.Although its clinical benefit is not yet proven, finding ways to
decrease free fatty acid levels in subjects at high risk for sudden death
may be a target for prevention,'' he said in a prepared statement.
Fatty acids are released into the blood by fat stored in tissue. The type
and levels found in the blood depend largely on diet.
Not all fatty acids are detrimental. In an accompanying editorial, Dr.
Alexander Leaf, a professor at Harvard Medical School (news - web sites)
in Boston, Massachusetts, suggests that increased consumption of omega-3
fatty acids, found in fish, may help to maintain a healthy balance of
fatty acids in the blood.
Studies have suggested that people with higher levels of omega-3 fatty
acids in relation to omega-6 fatty acids--found in vegetable oils--have a
lower risk of heart disease. However, Leaf stressed that the link remains
Sudden cardiac death usually occurs within 2 hours after symptoms of heart
attack begin. It can also occur independent of a heart attack, usually in
patients with cardiovascular disease. People who are at risk for sudden
death include heart attack survivors, individuals with diabetes and those
with a family history of sudden death.
Jouven said it is not entirely clear how fatty acids increase the risk,
but he suggests that high levels somehow cause the muscle cells of the
heart to beat irregularly.
Other factors found to be associated with increased risk of sudden death
included being overweight, high blood pressure, smoking, family history of
sudden death and cholesterol levels, the researchers note.
SOURCE: Circulation 2001;104.
Mental Alertness and Cardiac Diseases
- Dementia's Not All in Your Head -- Your Heart Plays a Part A Heart-Healthy Lifestyle Can Greatly Decrease Your Risk of Dementia By Norra MacReady WebMD Medical News
May 2, 2000 (San Diego) -- Before you grab that double cheeseburger, consider this: If you're middle-aged with two or more risk factors for heart disease, such as obesity and high cholesterol, your risk for dementia by your late 70s is greatly increased. Research detailing the connection between the head and the heart was presented here at the 52nd annual meeting of the American Academy of Neurology.
Dementia is a gradual breakdown in mental function characterized by memory loss, disorientation, and decline in judgment and intellect, lead researcher Sandra Kalmijn, MD, PhD, tells WebMD. Most people think of it in conjunction with Alzheimer's disease, but it has been linked to other conditions as well, such as strokes or mini-strokes.
The findings of this study reflect the long-term, negative effects of what the authors call "syndrome X," a clustering of heart-disease risk factors in one individual. Dementia risk was found to be low among men with no risk factors or only one. Obesity and a high level of certain fats in the blood were the factors most strongly associated with an increased risk of dementia. There was no association between these risk factors and the risk of developing Alzheimer's disease, says Kalmijn, an investigator at the National Institute on Aging (NIA) in Bethesda, Md.
"The point is that these risk factors seem to cluster in certain people," senior researcher Lenore J. Launer, PhD, tells WebMD. People with syndrome X have a higher risk of both heart disease and dementia, she says. Launer is chief of neuroepidemiology at the NIA.
To conduct their research, Launer and her colleagues studied participants in the Honolulu Heart Program. Between 1965 and 1968, this program enrolled all men of Japanese descent living in Honolulu, with the purpose of tracking the effects of various risk factors on heart and blood vessel disease. More than 3,500 men took part, and their average age was 53. In follow-up examinations conducted between 1991 and 1993, 215 of the then elderly men were found to be demented.
"These findings suggest that risk factors in middle age influence the risk of dementia later on," Kalmijn tells WebMD. To her, one of the most interesting findings was the association between obesity and dementia. "If one risk factor is elevated, there's a chance that the others are elevated, too," Kalmijn says. "By losing weight, exercising, stopping smoking, and eating more fruits and vegetables, you can lower most of those risk factors."
"This is an interesting study on a huge number of patients. I think the findings are [relevant]," says Thomas Arnold, MD, a neurologist at the University of Tennessee in Memphis who was not involved in study. "It is not a huge surprise that obesity is a risk factor [for dementia]," Arnold tells WebMD in an interview asking for an expert opinion of the work. "It's best to exercise, not be overweight, and not eat too much fat -- but most patients already know that."