Definition: Heart block is a type of arrhythmia that causes an abnormal heart rhythm where the heart beats too slowly, also referred to as bradycardia. The electrical signals that tell the heart chambers to contract and pump blood are partially or totally blocked between the upper and lower chambers.
Example: The different types of heart blocks include a first-degree heart block, a second-degree heart bock (type 1), a second-degree heart block (type 2), third-degree heart block, and bundle branch block. While not everyone experiences symptoms, many people experience chest pain, shortness of breath, dizziness, or fainting. Risk factors for heart block can include aging, prior heart attack, heart failure, heart valve abnormalities, heart valve surgery, some medications or exposure to toxic substances, and Lyme disease.