Arrhythmias, or irregularities in the heart's rhythm, are common medical conditions and can range from minor to life-threatening. The two most common arrhythmias are Atrial Fibrillation (AF) and Premature Ventricular Contractions (PVCs). AF is an irregular and often rapid heart rate caused by disorganized electrical activity in the atria. PVCs are extra, “premature” heartbeats that occur in the ventricles. Both arrhythmias can lead to palpitations, chest pain, shortness of breath, and fatigue, and can be triggered by certain medications, stress, or other medical conditions. To diagnose arrhythmias, doctors use ECGs and Holter monitors to measure the heart's electrical activity. Treatment for arrhythmias varies depending on the type and severity, and may include lifestyle changes, medications, or implanted medical devices such as pacemakers.