Research is constantly under way to better understand how the human body works. Refined surgical techniques, new drugs and disease treatments are providing doctors with better tools to keep patients healthy. Such advances may promise new life for the approximately 16 million people who live with various forms of coronary heart disease.
During the past few years a procedure known as transmyocardial revascularization (TMR) has become a popular alternative to traditional artery-clearing treatments, such as angioplasty, bypass surgery and drugs.
In TMR, a doctor uses a laser to cut between 20 and 40 one-millimeter “tunnels” in the heart in order to increase blood flow. The laser shoots through the heart’s left ventricle while it is filled with blood—this protects the inside of the heart. To seal the outer openings but keep the inner channels open, the doctor presses one finger on the outside opening of the channel. This allows oxygen-rich blood to flow through the heart muscle and encourages new blood vessels to grow.
TMR candidates include those who …
- are too high risk for a second bypass or angioplasty
- have a blockage that is too widespread to be treated with bypass alone
- develop new buildup after a heart transplant
Most TMR patients go from having chest pains that awaken them from sleep to experiencing discomfort only upon exertion.
Although still in clinical trials, gene therapy appears to hold much promise. The treatment involves introducing a gene into the heart to stimulate the growth of new blood vessels. These new vessels feed blood to the heart when other arteries are too clogged to do so. In effect, gene therapy makes it possible for the heart to grow its own bypass. The gene can either be injected into the heart or taken as a pill.
In a test case, gene therapy relieved angina in 24 people who had had at least one heart attack and an average of two bypass surgeries. Prior to undergoing gene therapy, some patients had as many as 60 angina attacks in one week. After the therapy, they only experienced chest pain about three times a week.
Gene therapy is also being tested to prevent high blood pressure and high cholesterol, two risk factors for heart disease.
Researchers are also working on ways to speed the diagnosis of heart attack. For example, a simple blood sample can now tell doctors whether a patient has had a heart attack. By being tested for an enzyme called creatine-kinase MB, which is released by dying heart cells, patients can find out within hours if they’ve had a heart attack. This test can replace the series of tests normally given.