Hidden Heart-Attack Risks (PART 3)

ULTRAFAST scanning of coronary arteries has been used clinically now for about seven years. Proponents say that scanners are capable of spoting trouble long before an angiogram. The test also can motivate people to lower their risk.


Take Frank Ward, a Chicago contractor who was nearing 50 when he heard a radio advertisement for the test at the University of Illinois. Although Ward had moderately high Cholesterol, he considered himself healthy. But he decided the CAT scan would be a great way to persuade his overweight business partner, Dave, to pay attention to his health.

"All I had to do was lie on a table for 15 minutes," Ward remembers. "But when the report came back, I thought they'd given me Dave's results by mistake."


Ward's calcium reading was 392, far too high. His hefty partner's score: a much more acceptable 17. An angiogram revealed an 85-per-cent obstruction near Ward's aorta. He underwent angioplasty and had a stent inserted, and today is doing well on cholesterol medication.


Leg Blockages


Doctors can get information about a patient's arteries just by adding an extra step to a routine blood-pressure test: taking a blood-pressure reading around the ankle. The ankle reading is divided by the arm reading. Any number equal to or below 0.9 is a danger sign.


The aim is to detect blockages in leg arteries, a sign that trouble may be brewing in the coronary arteries. Some people with leg-vessel obstructions have pain when they walk and get relief at rest. "But half the patients have no pain, Dr. Michael Criqui at the University of California, San Diego.


The test seems to be a powerful predictor of life-span. Criqui, who studied 565 people age 66 or above, found that over a ten-year period, those with an ankle/arm index of 0.8 or less were five times likelier to die of cardiovascular disease than people with a higher index. Such patients can be given the appropriate treatment, including cholesterol-lowering drugs, anti-hypertensis or surgery.


ON THE HORIZON, researchers are looking into a blood test to measure C-reactive protein, a substance indicating inflammation of blood-vessel walls. This test derives from the new theory that inflammation--possibly as a result of chronic microbial infection-contributes to the clogging of arteries. If this is true, it raises the prospect of treating heart disease with antibiotics and vaccines.


Another new approach to heart attack prevention is gene testing. "Of some 100 different risk factors that may pave the way for coronary-artery disease, many are genes or environmental components that interact with genes," says Dr. Roger Williams of the University of Utah School of Medicine. As, scientist identify these genes, we'll detect the ones that increase heart-attack risk, and then scan people's DNA to learn who need who needs treatment."


Should you be tested for any of these hidden heart-attack risks? Today the tests are available to most people, but they can be expensive. "Patients should discuss this with their doctors," advises Dr. Phillip Greenland, chairman of the department of preventive medicine at Chicago's Northwestern University Medical School.


All five test are available in some parts of Asia, including Singapore and Hongkong. For more information, have your doctor contact a university medical center with a high risk or preventive-cardiology section. Or visit the American Heart Association's website at www.amhrt.org or HeartInfo, an independent educational Web site co-founded by Dr. Rader, at www.heartinfo.org

Continue Reading»

Posted in: Disease,Health,Heart Attack,HeartAttackRisksFactors,Medical

Hidden Heart-Attack Risks (PART 2)

WHAT seems to make Lp(a) so troublesome is its uniqe design. Ordinary LDL is a ball of cholesterol wrapped by a strand of a protein. As LDL travels through an artery, this protein can latch on to plague and deliver the cholesterol wrapped by a strand of a protein. As LDL travels through an artery, this protein can latch on to plague and deliver the cholesterol cargo. But Lp(a) has an extra protein strand that's shaped like a natural clotbuster in the blood. Since plagues are known to contain blood closts, scientists suspect this look-alike protein actually tricks blockages into soaking up more cholesterol instead of clotbuster.

Special blood tests can identify the problem, but neither a low-fat diet nor most drugs that Lower LDL will budge high levels of Lp(a). Two exceptions are physician-supervised doses of the B vitamin niacin and, for women past menopause, estrogen.

Homocysteine

This amino acid, found in everyone's blood, is estimated to figure in ten to 15 percent of heart attacks, and 30 to 40 percent of strokes. A high homocysteine level is considered to be above 14.

In the 1960's at Boston's Massachusetts General Hospital, doctors examine a young girl wiht a genetic disease that cause a buildup of homocysteine in the blood. The girl had a relative who had died at the age of eight from a similar illness 30 years earlier at the same hospital. When Dr. Kilmer McCully dug out the old records and peered through his microscope at tissue from the long-dead    child, he realized that the boy had the arteries of an old man.

Several months later McCully's antennae were alerted by news of a two-month-old  boy who died of another genetic disease that caused homocysteine buildups. When he looked at this baby's tissue samples, once again he saw clogged arteries. "I began to suspect that people whose homocysteine levels were high might be at risk for heart attacks," recalls McCully.

McCully's theory produced controversy and led to further research. Finally, three decades later, a major study at harvard and Bringham and Women's hospital looked at nearly 15,000 male physicians over five years. In this health-conscious group, only 271 suffered heart attacks. High homocysteine coincides with a deficiency of the B vitamin folic acid and, in some cases vitamin B-6 and  B-12. "people who have five daily servings of green leafy vegetables, beans and citrus fruits or juices can get the required 400 micrograms of folic acid," says Dr. Jacob Selhub, a professor of nutrition.

But doctors estimate that only a small percentage of the population eats that much folic-acid-rich food. "If there's a choice between not getting the vitamin or taking supplements," says Dr. Meir Stampfer of the Harvard School of Public health, I'd choose the supplements." Stampfer adds that the ederly may need suplements because the ability to break down homocysteine declines with age.

Fibrinogen

This substance, protein that helps form blood clots, gained much attention in 1986 when British researchers measured fibrinogen levels in the blood of male workers at a food-processing plant over a five-year period. The scientists discovered that men with a fibrinogen level in the upper third had an 84-percent increased risk of ischemic heart disease over those in the lower third. Since then other studies have added to this evidence.

Although high fibrinogen levels are link to heart-attack risk, science hasn't yet  demonstrated a cause and-effect relationship. But one theory is that the more fibrinogen, the bigger the clots that form after an atherosclerotic plaque breaks.

When Dominic Aievoli had a fatal heart attack at 55, his wife's grief was compounded by her fear that her two sons might also be in danger. Her worries were confirmed when doctors found excessive amounts of two troublemakers in 26-year-old David's blood. One was Lp(a0; the other, fibrinogen.

A first-line defense against surplus fibrinogen is to declare war on other substances that damage arteries. But it may also be possible to battle fibrinogen itself. "Since levels are higher with obesity or hypertension, controlling weight and blood pressure may lower readings," Rader says.

Exercise also lowers levels. David Aievoli has taken up running, and his fibrinogen has been cut.

Calcium Deposits

Calcium accumulates in arterial blockages, which are made up of cholesterol and other substances. One day Dr. Bruce Brundage, a cardiologist at Bend Memorial Clinic in Oregon, had a brainstrom while studying a new CAT scanner capable of taking X rays of the heart between heartbeats. "It dawned on me that this ultrafast scanner could capture sharper images of calcium," says Brundage. "If a scan showed a lot of calcium in a patient's arteries, that person was at increased risk of having dangerous obstructions."

To be continued - Hidden Heart-Attack Risks (PART 3)                                                                                                                                                                                                                                                                                                  

Continue Reading»

Posted in: Disease,Health,Heart Attack,HeartAttackRisksFactors,Medical

Hidden Heart-Attack Risks (PART 1)

These factors can make you more vurnerable, yet won't show up on conventional tests.


DR. MARK GOLD was only seven when his father, age 42, has third heart attack. "The doctor said I should go into the bedroom and talk to my father," he recalls. "It was only later that realized he was telling me, 'Your father is dying. Say goodbye.' The older I get, the more I feel the pain of losing him so early."


Now 52, Gold has a son and daughter of his own. "I don't want to put them in the same position," he says.

Gold's own battle with heart disease began in 1988, when he felt mild chest discomfort while jogging. The-five-foot-seven-inch ophtalmologist weighed under 140 pounds and, other than his family history, had no commonly known risk factors for heart disease. His cholesterol was 203, just above the American   Heart Association's "desirable" level of 200.


Yet an angiogram showed a blocked artery, and Gold was put on medication. I was doing everything right," he says. Nonetheless, one day in 1994 when he went out walking, the pain was there again.


This time doctors found two blocked arteries, so Gold had bypass surgery. "I knew I had a progressive disease that runs through my family," he says. "But what runs through it, I wondered."


Gold's question led him to Dr. Daniel Rader, director of the University of Pennsylvania's Preventive Cardiology Program, who gave him a battery of special tests. One blood test revealed a sky-high level of a worisome fat particle called Lp(a) that may raise heart-attack risks even when the usual cholesterol readings are fine. The typical Lp(a) reading in Caucasians and Asians is under 20; Gold was 88. Fortunately Rader was able to lower it by putting Gold on a special niacin regimen.


A growing number of programs similar to the one at the University of Pennsylvania are uncovering hidden heart-attack risks. Surprisingly many individuals can't assume they're safe. In the Framingham Heart Study, an ongoing analysis of some 11,000 residents of Framingham, Massachusetts, 17 percent of people with early heart disease had none of the "big four" controllable risks: high cholesterol, high blood pressure, diabetes or smoking.


Testing for hidden risks is "most important for people with an ominous family history---at least one-third of the population," says Rader.


"That means a heart attack or chest pain in a male relative by age 70, including grandparents, aunts and uncles."


Others who could benefit are those who already have a risk, such as high cholesterol or who have been diagnosed with heart disease, even though they have no known risk factors.


Here are five newly recognized heart-attack risk factors and what we know about them:


1. Lp(a)


Until now, the substance in the blood getting most of the blame for heart attacks has been "bad" LDL cholesterol. But researchers have begun to recognize that one particular member of the LDL family, Lp(a), carries an additional heart risk.


A Survey of women from the Framingham research showed that a very high Lp(a) level (generally 35 to 40) more than doubled the risk of heart attack. In a study of patients with premature coronary-artery disease, done mainly at Tufts University and New England Medical Center Hospital, there was an "excess" of Lp(a) in 19 percent of the group.


to be continued - Hidden Heart Attack Risks (PART 2)

Continue Reading»

Posted in: Disease,Health,Heart Attack,HeartAttackRisksFactors,Medical