Atheriosclerosis - Exposure to second hand smoke speeds progression of atherosclerosis
Exposure to second hand smoke speeds progression of atherosclerosis
A build up of plaque inside the arteries, according to a new study which also suggests that the negative effects of smoking may be irreversible. The study which was published in the Journal of the American Medical Association, analyzed 10,914 middle aged adults enrolled in the Atherosclerosis Risk in Communities study between 1987 and 1989. Researchers examined the carotid arteries in the neck which supply blood to the brain. Narrowing of these arteries can mean atherosclerosis exists in other arteries such as those that feed the heart muscle. The study found that compared to people who had never smoked, smokers had a 50% increase in the progression of atherosclerosis and past smokers had a 25% increase. Compared to those with no exposure, those who were exposed to second hand smoke had a 20% increase. The impact of smoking was greater for people with diabetes and high blood pressure. Atherosclerosis progression was related to the amount and duration of smoking but did not differ significantly between current and past smokers, suggesting the damage may be cumulative.and perhaps irreversible.
French researchers have found that plaques remain active following a heart attack far longer than was previously believed. After rupturing and producing blood clots that cause a heart attack, plaques (fatty growths) are still active sometimes weeks later and can still cause additional damage to the heart even though patients have taken aggressive anti-clot therapy. The researchers at Hospital Cardiologique in Lille,France, observed the diseased arteries in 56 heart attack survivors using a tiny camera inserted in the coronary arteries. In 77% of the patients, blood clots were visibly protruding from blood vessel walls and in more than half (54%) there was evidence that the plaques were not healing. Forty of the patients had received thrombolytic therapy to dissolve their clots at the time of their heart attack, but these patients were just as likely to have a vascular blood clot later as those who did not receive the drugs. It was previously believed that ruptured plaques heal within as little as a few days after a heart attack. The findings of this new study, which was published in Circulation, a journal of the American Heart Association, could have a significant impact on post heart attack treatment procedures.
A simple blood test that measures white blood cells levels may help predict long term survival in prospective transplant patients with congestive heart failure, according to new research. In a study of 211 men with heart failure who were awaiting heart transplants, researchers found that the patients with low lymphocyte levels were more likely to die than those with normal levels of this type of white blood cell that is made in lymph tissues. The survival rate was 34% for those men with concentrations of less than 20.3% compared to 73% in those subjects who had concentrations over 20.3%. The finding that lymphocyte concentrations are significantly related to survival could help in the selection of appropriate patients for heart transplants. The study was published in Circulation, a journal of the American Heart Association.