When the heart rate is less than 60 beats per minute it is calledsinus bradycardia Causes Physiogical
1. During deep sleep.
2. Athletes.
1. Viral infection.
2. Obstructive jaundice.
3. Hypothyroidism
4. Carotid sinus syncope.
5. Increased intracranial tension.
6. Sick sinus syndrome.
7. Hypothermia.
8. Myocardial infarction.
9. Gram negative sepsis.
10. Vasovagal fainting attack.
11. Some cases of severe anemia.
12. Aortic stenosis.
13. Mallory Weiss syndrome.
14.Boerhaave’s syndrome
15. Drugs: Digitalis, Betablocker, Calcium Antagonists
(Verapamil, Diltiazem), Amiodarone, Cimetidine, Clonidine.
16. Giant left atrium.