Arrhythmias

Excerpt

Arrhythmia is an abnormal rhythm of the heart. The only normal rhythm of the heart is a normal sinus rhythm. In this rhythm, an impulse is generated in the sinoatrial (SA) node, which is conducted through and slowed down while passing through the atrioventricular node (AV). It is then conducted through the bundle of His, to the left and right bundle branches, and eventually into the Purkinje fibers. Any deviation from this conduction pathway results in arrhythmia. Arrhythmias can be classified based on various criteria. The most common way to categorize them is based on the rate of conduction as bradyarrhythmia with a heart rate of fewer than 60 beats per minute (bpm) and tachyarrhythmia with a heart rate higher than 100 bpm.