DOCTOR'S VIEW ARCHIVE
Heart Disease & Stroke - Progress Through Research
Gene therapy designed to grow new blood vessels in the heart muscle led the list of the top 10 research advances in heart disease and stroke compiled by the American Heart Association. The list, first created in 1996, recognizes achievements in basic and clinical research that may have the most impact on the prevention and treatment of cardiovascular disease.
The most recent edition of the list is as follows:
This list was issued at the end of 1999 by the American Heart Association and is based upon developments reported during 1998. We will comment upon each of these ten advances:
1. Gene therapy to create a "natural" bypass to circumvent
plaques obstructing the heart's blood vessels.
Scientists reported that they had used a human growth factor called FGF-1 (fibroblast growth factor-1), obtained through genetic engineering, to induce the growth of new blood vessels in 20 patients with heart disease. In their three-year follow-up study of the patients, the scientists reported that the treatment resulted in a two to three times more blood flow to the heart.
Another growth factor called VEGF (vascular endothelial growth factor) also appears capable of inducing new blood vessel growth for the heart. Gene therapy may thus become an important part of the treatment of heart disease.2. New drugs to prevent clots causing heart attacks and strokes.
Drugs called platelet blockers (or, more formally, IIb/IIIa receptor blockers) were found to keep blood platelets from clumping and forming blood clots that can trigger a heart attack or stroke. In this regard they are like aspirin. However, the platelet blockers -- eptifibatide (brand name: Integrilin), tirofiban (Aggrastatin) and abciximab (ReoPro) -- are more potent than aspirin. And they are administered intravenously (IV).
To test the usefulness of the platelet inhibitor drugs, a total of about 32,000 heart patients received a platelet blocker as part of their treatment for a heart attack or severe chest pain. Some individuals received only the platelet blockers while others were treated with a platelet blocker plus angioplasty -- a procedure that uses a balloon-tipped catheter to restore blood flow in the blood vessel. Those who received the platelet blockers had a 30 percent reduced risk of all-cause death than those who did not receive the drugs. The individuals who particularly benefited from the drugs were those who also were treated with angioplasty. In these individuals the drug was administered just as the coronary arteries were being opened by inflation of the balloon-tipped catheters used for the procedure.
3. Relationship between inflammation and heart attacks.
The area of the blood vessel where an obstructive plaque develops can become inflamed. The inflammatory response may not be localized to the blood vessel wall in that area. It also can occur throughout the bloodstream. This systemic inflammation may explain the development of blood clots on top of relatively stable plaques.
4. Detection of unstable plaques in vessels by imaging