Advances in Understanding and Treating Heart Disease

2010 also brought advances in medical technology that may make treating heart disease simpler, less expensive, and less invasive. One of the most important is a blood test that can predict heart attack risk.

A blood test may be even more useful than a treadmill test

After the age of 40, many doctors want all of their patients to take a stress test for heart disease. Patients are injected with a radioactive dye, put on a treadmill that runs faster and faster and at a steeper and steeper slant until their hearts are beating at a maximum rate, and then they are put in a CAT scanner to detect arterial blockages. Researchers at the University of Texas Southwestern Medical Center in Dallas have developed a blood test that may offer much of the same information. A very sensitive assay for a protein called troponin, the same protein that is found in the bloodstream after a heart attack, this test can identify patients who are up to 7 times more likely to have a future heart attack even without testing on a treadmill.

The heart renews itself more and more quickly as we age

After the age of 65, many heart patients are given less aggressive treatment on the assumption that aging hearts can't mend. A study at Brigham and Women's Hospital in Boston found that this assumption simply is not true. Stem cells are found in the body throughout life. Our bodies use our own stem cells to make replacement tissues, although the process is not as dramatic as the action of stem cells in the embryo. To the investigators' surprise, the older we get, the more stem cells our hearts produce to renew aging tissue. In a study of people aged 19 to 104, scientists found:

•    At age 20, heart cell renewal rates were 10 percent in women and 7 percent in men.
•    At age 60, heart cell renewal rates were 15 percent in women and 12 percent in men.
•    At age 100, heart cell renewal rates were 40 percent in women and 32 percent in men.

The older you get, the more power your heart has to heal itself. Men's heart tissues are programmed to "wear out" faster than women's heart tissues, but the net effect is to give men's and women's hearts similar function.