Cardiac arrhythmias are abnormalities in the heart's rhythm that can cause symptoms ranging from palpitations to sudden death. The two main types are bradycardias, which are slow heart rates below 60 bpm, and tachycardias, which are fast heart rates over 100 bpm. Arrhythmias can arise from problems in the sinus node, atria, AV junction, or ventricles due to issues with automaticity or re-entry of electrical impulses. Common arrhythmias include sinus tachycardia/bradycardia, premature beats, atrial fibrillation, and heart blocks. Treatment depends on the specific arrhythmia and symptoms but may include lifestyle changes, medications