New Drug May Help Prevent Sudden Death
April 8, 2004 -- An experimental new drug may one day help prevent sudden death in millions of people with heart failure or inherited heart defects that put them at risk for potentially dangerous heart rhythms known as arrhythmias, according to initial animal tests of the drug.
Arrhythmias of the lower chambers of the heart, called ventricular arrhythmias, are a common cause of sudden death, especially among people with heart failure. Researchers estimate that about half of the 4.6 million people with heart failure will die from ventricular arrhythmia, which produces a fast, erratic heartbeat.
Many of the previous medications designed to treat ventricular arrhythmias have proven too toxic and have been removed from the market.
But a study in the April 9 issue of Science showed that the experimental drug safely prevented ventricular arrhythmias in mice bred to have the same defect that causes these arrhythmias in humans. Further studies are necessary to see if the drug works the same way in humans.
Drug May Stop Arrhythmias
In the study, researchers treated 10 mice with the experimental drug. The mice were bred to have a defect that causes calcium to leak from heart muscle cells. This leak can trigger a fatal arrhythmia in people with heart failure or during exercise in people with a certain genetic defect in their heart.
The study showed that all 10 mice treated with the experimental drug, known as JTV519, survived and never developed an arrhythmia. In comparison, eight of nine untreated mice with the same defect developed arrhythmia and died.
Researchers say the drug works by patching the leak. They say it may also have the potential to slow the decline in heart function associated with heart failure.
"By fixing the leak, you could potentially slow the progression of heart failure and allow patients to live their lives more normally, not in and out of hospitals," says researcher Andrew Marks, MD, director of the Center for Molecular Cardiology at Columbia University Medical Center, in a news release. "Our idea is to take a pill instead of spending hundreds of thousands of dollars on implants and heart transplants."