Jewish World Review June 7, 2002 / 27 Sivan, 5762

New coronary artery stent reduces risk of restenosis

By Robert A. Wascher, M.D., F.A.C.S. | In the past, people with clinically significant narrowing of their main coronary arteries all required open heart surgery and coronary bypass grafting to restore blood flow to the heart. More recently, however, coronary artery stents (expandable mesh tubes that resembles those paper "Chinese handcuffs" you played with when you were a kid) have made it possible for many patients to avoid going under the surgeon's knife.

These diminutive vascular conduits are threaded-up through an artery in the leg or arm, and are then passed through the area of blockage in the affected coronary artery. These internal bypass devices have a very high rate of success in restoring coronary artery blood flow but, in 25 to 40 percent of cases, the body responds to the device by gradually narrowing the stented artery again. A number of approaches have been taken to reduce the incidence of restenosis in stented arteries.

In this week's New England Journal of Medicine is a study that looked at rapamycin-impregnated stents as a novel way of reducing the restenosis rate. Rapamycin is often used as an anti-rejection medication in transplant patients, as the drug inhibits certain immune cells from dividing and attacking the transplanted organs.

The researchers coated coronary artery stents with rapamycin, and then randomized 238 patients to receive either a rapamycin-coated stent or a non-coated stent. The patients were then followed for at least one year after stenting. The patients who had the rapamycin-coated stents implanted were found to have significantly less restenosis than patients receiving the conventional stents.

After being observed for 12 months, fully 27 percent of the patients with conventional stents developed at least a 50 percent reduction in the diameter of the stented artery, while none of the patients with the rapamycin-coated stents experienced a comparable degree of reduction in arterial diameter. Most importantly, 29 percent of the standard-stent group experienced a heart attack, death, or the need for emergent bypass during the 12 month follow-up period, while only 6 percent of the rapamycin-coated stent group experienced any of these severe complications of coronary artery restenosis.

This study convincingly demonstrated a dramatic reduction in the most common complication associated with coronary artery stents, and along with other similarly successful interventions, further advances the state of the art of non-surgical coronary artery disease treatment.


Parkinson's Disease (PD), which affects about 1.5 million Americans, is a neurological syndrome that causes tremors, difficulties in starting and stopping movements, a peculiar stiffness of the body, depression and, in some cases, dementia.

The area in the brain that is affected by the disease is known as the substantia nigra, and is thought to be an important relay system for nerve cell impulses involved in movement. For reasons that have eluded scientists since it was first described in 1817 by the British physician James Parkinson, dopamine-secreting neurons in this area of the brain die off, causing the symptoms of PD.

However, a new study, just reported in Nature Medicine, has identified at least one possible cause of Parkinson's Disease. A brain protein called alpha-synuclein is known to be elevated in the substantia nigra of most patients with PD. In this study, the scientists added alpha-synuclein to healthy substantia nigra neurons growing in a culture dish, and observed that this protein actually appeared to convert the dopamine secreted by substantia nigra neurons into a toxic compound which then, in turn, killed the neurons. Ironically, alpha-synuclein appears to have a protective effect on neurons that do not secrete dopamine in other parts of the brain.

Most spontaneous cases PD have long been suspected to arise from exposure to unknown environmental toxins. It is, therefore, especially intriguing that this Nature Medicine study concluded that alpha-synuclein converts dopamine into a neurotoxin by way of oxygen free radicals, which are byproducts of normal metabolism, and the metabolism of numerous drugs and toxins as well. If alpha-synuclein does in fact cause or mediate the onset of PD, this knowledge could serve as a critical starting point for the development of drugs that target this protein, or the free radicals that also appear to be involved. PD might then be prevented in many cases or, at least, more effectively treated than is possible at the present time.


Bioflavanoids are in the news a great deal these days. Antioxidant flavanoids contained in tea and other natural sources are thought to have a variety of beneficial effects, including the elimination of potentially harmful free radicals that have been linked to an increased risk of heart disease and some cancers. The journal Cancer Research is reporting that silibinin, a flavanoid found in the milk thistle plant, is capable of significantly inhibiting the growth of human prostate cancer cells implanted in mice. Silibinin reduced tumor volume in these mice by 53 to 64 percent, and appeared to have virtually no observable toxicity. Human studies using this compound are currently being planned.

A Duke University team has studied pregnancy and birth rates among unmarried teenagers in Texas. They found that conception rates dipped during the summer months, and then dramatically increased again when school started in the fall. Their conclusion, not surprisingly, was that most teens meet their sexual partners at school....

When breast cancers spread, their favorite target is the skeletal system. Traditionally, a nuclear medicine bone scan is utilized to evaluate breast cancer patients for possible spread of their cancer to their bones. The nuclear medicine bone scan has been around for decades, and is very sensitive to any disruption of the bone caused by inflammation, injury or tumors.

Unfortunately, arthritis, relatively minor injuries and infections can all cause a positive bone scan result, making this test rather nonspecific as a cancer detection tool. PET scans, on the other hand, are both very sensitive and very specific for tumors. In the Journal of Cancer Research & Clinical Oncology, a new study has compared the two types of scans, and has found PET to be as sensitive as bone scans in detecting metastatic breast cancer lesions in the bone.

However, unlike bone scans, PET was also found to be highly specific for metastatic bone tumors. In another words, bone scans picked up even subtle abnormalities in the skeleton, irrespective of whether cancer metastases were present or not. An abnormal PET scan, however, was far more likely to represent a true metastasis of breast cancer to the bone than an abnormal nuclear medicine bone scan.

JWR contributor Dr. Robert A. Wascher is a senior research fellow in molecular & surgical oncology at the John Wayne Cancer Institute in Santa Monica, CA. Comment by clicking here.


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05/24/02: Molecular detection of tumor cells in the blood & prognosis; Cox-2 & breast/lung cancers; BRCA2 gene mutations & the risk of breast cancer; breast density & the risk of breast cancer

05/19/02: Moderate alcohol intake and blood sugar levels; more good news for tea drinkers; blood potassium levels & the risk of cardiovascular disease; ethnic differences in diabetic complications

05/10/02: Tea drinkers and the risk of death following heart attack; duration of breastfeeding & adult intelligence; abdominal aortic aneurysms: surgery or observation?

05/03/02: Risk of adverse drug reactions from newly released medications; preoperative beta-blockers may reduce heart bypass deaths; shape-shifting plastics may alter surgical practice; weight loss supplement may cause liver damage
04/26/02: Angry young men & risk of premature cardiovascular disease; stay-at-home dads & risk of cardiovascular disease; more on the effects of statins; dairy consumption and the risk of pre-diabetes; smallpox vaccine: good to the last drop?
04/19/02: Change your sex by drinking water?; Anti-inflammatory RXs may reduce growth of breast cancer cells; radiation treatment reduces repeat narrowing of bypass grafts
04/05/02: Fish & Omega-3 fatty acid consumption and cardiac health; news briefs
04/05/02: Can coffee reduce your risk of tooth decay?; exercise & blood pressure; a single high-fat meal reduces coronary artery function
04/01/02: Pre-diabetes: a newly defined category of health risk; teen television viewing and subsequent aggressive behavior; the benefits of strength training in the elderly; more ...
03/22/02: Bacteria, antibiotics & heart disease; mammograms: the debate continues; calcium & the risk of colon cancer ... and more
03/15/02: Mammography debate continues; statins & fracture risk; physical fitness & the risk of death; other intriguing findings
03/08/02: Blows to the chest & sudden cardiac death; air quality & the risk of lung cancer; tomatoes and your prostate
03/01/02: Diet & the risk of ovarian cancer; lifetime risk of developing high blood pressure; Osteoporosis prevention with a once-a-year injection?
02/26/02: The continuing controversy regarding screening mammography
02/22/02: Lowering body temperature after heart attack improves outcome; A silver lining for the chronically sleep-deprived?
02/15/02: Hormone replacement therapy & the risk of breast cancer; use it or lose it: Alzheimer's disease & cognitive stimulation; stress, divorce & death; child daycare, infections & parental guilt
02/08/02: Possible breakthrough in early cancer diagnosis; mammography: the controversy continues; CPR techniques revisited
02/01/02: Antibiotics in livestock feed & human disease; genetic detection of early colon cancer in the stool; genetic analysis of breast cancers may help decide treatment
01/25/02: Drug increases lifespan (if you're a fly...); workplace attitudes and smoking cessation; effects of inadequate sleep on surgeons
01/18/02: Lifelong effects of premature birth; smokers under the knife; aspirin and cardiovascular health
01/11/02: Estrogen levels in the blood & breast cancer risk; Heart attack: sex and survival; dangerous lettuce invaders
01/09/02: Cancer & aging: Two sides of the same coin?
01/04/02: Vitamin a & the risk of hip fracture in postmenopausal women; ovarian cancer risk and oral contraceptives
12/28/01: Magnetic Resonance Imaging (MRI) detects coronary artery disease; new development in obesity research; adverse childhood experiences & the risk of suicide attempts
12/21/01: Vaccination of children controls hepatitis a in the community; a possible cure for sickle cell disease; leptin and the risk of heart attacks
12/14/01: Chernobyl and the Risk of Thyroid Cancer in hildren; children & obesity; gastroesophageal reflux disease update
12/07/01: Update on school shootings; new implantable heart-assist device approved for further evaluation; prevention of fungal infections in pre-term babies
11/30/01: Flu vaccination in asthmatics; low-tar cigarettes are not less harmful; beans and your heart
11/21/01: Modified smallpox vaccine may reduce risk of cervical cancer; New approach to breast cancer diagnosis; New non-invasive prenatal diagnostic test for down's syndrome
11/16/01: Cholesterol-lowering drugs reduce risk of heart attack; supplemental radiation therapy reduces risk of breast cancer recurrence; brains of women may answer age-old questions
11/09/01: Bio-warfare (redux); my gray matter is bigger than yours; mad elk disease?
11/02/01: Making sense of bio-warfare
10/26/01: The impact of mammography on deaths due to breast cancer; diet & exercise may slow cancer cell growth; antidepressants and the risk of heart disease
10/19/01: New insights into autism; the wiley appendix
10/12/01: More bad news about obesity links to other diseases…Hey dad, can I borrow the car keys?
10/05/01: California leads nation in reduction of tobacco-related disease; exercise as an antidepressant?
09/25/01: Advances in the detection of breast cancer; primary care physician awareness of peripheral arterial disease; arsenic in the water
09/17/01: In perspective
09/12/01: Genes may hold secret to long life; men and women: cognitive function in the elderly; physical activity, obesity and the risk of pancreatic cancer
09/05/01: English milk cows prefer Beethoven and Simon & Garfunkel over Bananarama; new prostate cancer prevention study: looking for a few good men; exercise & diet can help prevent diabetes
08/28/01: Arthritis drugs may be linked with increased risk of heart disease; errors in blood clotting tests can be fatal; infant soy formula not associated with reproductive side effects

© 2002, Dr. Robert A. Wascher