Researchers at the University of California, San Francisco, have found that alcohol can be deadly for people with heart rhythm disorders such as atrial fibrillation.
In fibrillation, the pumping of blood through the atria, which normally occurs through the rhythmic flow of nerve impulses through muscle cells, is disrupted. During a malfunction, the electrical signals begin to flow chaotically through the muscle tissues, causing the heart to stop pumping blood effectively. Atrial fibrillation affects 12 million people in the United States, and 158,000 people die each year. The condition also contributes to blood clots and strokes.
The subjects underwent a standard catheter ablation procedure, which is an effective method of inhibiting fibrillation. It is designed to eliminate the passage of the electrical impulse between the pulmonary veins and the left atrium. Scientists measured the refractory period needed for cells to regain the ability to form an action potential.
It turned out that alcohol lowered the refractory period in the pulmonary vein by 12 milliseconds and also contributed to its reduction at a large number of atrial sites. This increases the risk of arrhythmia, the scientists noted.