Why does the pain occur in angina pectoris?

The pain comes as a consequence of the lack of oxygen in the heart muscle, which in turn, comes as a consequence of lack of blood circulation in the heart blood vessels (less blood circulating). The lack of oxygen triggers interoceptive nerve endings.

Throughout this buildup of low oxygen levels in the system, the buildup of other molecules is observed such as lactic, pyruvic and phosphoric acid, which come from the anaerobic metabolism of the heart muscle (the muscles produce energy without oxygen, and thus produce the aforementioned dangerous acids as byproducts of the anaerobic (without oxygen) metabolism).

Medically Reviewed by a doctor on 24 Jan 2018
Medical Author: Dr. med. Diana Hysi