This ECG shows P waves that are not always associated with a QRS complex. This is called "AV dissociation" and occurs in complete heart block (a.k.a. 3rd degree heart block). In this situation, the P ...

First-degree ventricular (heart) block affects the electrical signal that makes the heart beat. It causes a delay in a portion of the heart beat and may lead to a slow heart beat. Healthcare ...

Second-degree heart block is a potentially serious but treatable condition affecting the heart’s electrical system. Treatment may require a pacemaker to stabilize the heart’s rhythm. Electrical ...

First-degree heart block is the mildest type and often requires no treatment. Third-degree heart block is the most severe and ...

Complete heart block means that there’s a complete separation of electrical activity between the upper and lower chambers of the heart. Without prompt medical attention, it can be fatal. Your heart ...

Heart block is a type of arrhythmia that affects the electrical system of the heart and causes it to beat irregularly and slower than usual. A third degree heart block is the most serious type. It can ...