antiarítmico

An antiarrhythmic is a medication used to treat abnormal heart rhythms, also known as arrhythmias. Arrhythmias occur when the electrical signals that control the heart's beat are disrupted, causing the heart to beat too fast, too slow, or irregularly. Antiarrhythmics work by affecting the electrical activity of the heart's cells, specifically by influencing the movement of ions like sodium, potassium, and calcium across cell membranes. This modulation helps to restore a normal heart rhythm.

There are several classes of antiarrhythmic drugs, each with a different mechanism of action. Class I drugs, for example, block sodium channels, slowing the conduction of electrical impulses. Class II drugs, such as beta-blockers, reduce the heart rate and the force of contractions by blocking the effects of adrenaline. Class III drugs primarily affect potassium channels, prolonging the repolarization phase of the cardiac action potential. Class IV drugs, calcium channel blockers, decrease the influx of calcium into heart cells, slowing conduction through the AV node and reducing heart rate.

The choice of antiarrhythmic medication depends on the specific type of arrhythmia, the patient's overall health, and the presence of other medical conditions. These drugs can be administered orally, intravenously, or sometimes as injections. While effective, antiarrhythmics can also have side effects, some of which can be serious. Therefore, they are typically prescribed and monitored by healthcare professionals.