Cardiac dysrhythmia is an abnormal heart beat:
- rhythm may be irregular in its pacing or the heart rate may be low or high
- some dysrhythmias are potentially life threatening while other dysrhythmias (such as sinus arrhythmia) are a normal variant
Heart rate and origin (atria or ventricles) are used to help classify cardiac dysrhythmias.
Tachycardia is a fast (over 100 beats per minute) heart rhythm
- tachycardias can originate in the atria or ventricles.
Dysrhythmias that originate in the atria are termed supraventricular dysrhythmias (supraventricular means above the ventricles).
- these dysrhythmias include:
- atrial flutter
- atrial fibrillation
- paroxysmal supraventricular tachycardia
- atrial tachycarda
- sinus tachycardia
Ventricular dysrhythmias originate in the ventricles and include:
- ventricular fibrillation
- ventricular ectopics
- ventricular tachycardia
Bradycardia is a slow (under 60 beats per minute) heart rhythm.
Bradyarrhythmias are slow heart rhythms arising from disease in the cardiac electrical conduction system.
- sinus bradycardia
- atrioventricular conduction block
- sick sinus syndrome
A premature beat is an extra beat, occurring earlier than normal - it is termed an ectopic beat and may be atrial or ventricular in origin
- despite being an extra beat, patients may indicate feeling a "skipped beat"