Why are women with heart failure at risk for dangerous heart rhythms?
In women with heart failure the heart does not pump as efficiently as it should, either because of damage to the heart muscle from a heart attack or toxins, or because gradual changes over time have caused the heart’s walls to thicken and become stiff. This damage impairs the heart’s mechanical ability to pump blood, but it can also damage the electrical pathways along which the heartbeat travels. To pump blood effectively, the heart muscle must contract in a coordinated fashion with a regular speed and rhythm. The heart has an electrical system that carries signals telling different areas of the heart muscle when to contract. An arrhythmia is a disturbance in the heart’s normal rhythm. There are many types of arrhythmias, but the most dangerous ones in women and men with heart failure are ventricular tachycardia and ventricular fibrillation. The ventricles are the main pumping chambers of the heart: if they contract too quickly, it is called tachycardia. If the ventricle contracts in
