.jpg)
Cardiac Pain Referral Mechanism
Definition: The manifestation of caridiogenic pain at a somatic site adjacent or distal to the actual site of injury. Cardiac referred pain is the sensation of pain in the left side of the face, neck, chest, and left upper limb which can sometimes occur on the right in cases of dextrocardia.
Causes: The usual causes of cardiac referred pain include: myocardial infaction or heart attack, dissecting aortic aneurism The precise mechanism behind the referred pain phenomenon remains poorly understood. Cardiac visceral afferent fibres run with the sympathetics back to the spinal cord, where their cell bodies located in the dorsal root ganglia of T1 to T5. The central nervous system interprets cardiogenic pain as of somatic origin corresponding to the T1 to T5 segments. In addition to this, the dermatomes corresponding to this spinal level (T1 to T5) have their cell bodies located in the dorsal root ganglia, and synapse at the same spinal segment as the visceral afferents from the heart. It is suggested that there is some sort of confusion in the interpretation and differentiation of pain.
Examination: In a clinical setting, one must consider cardiac referred pain when assessing a patient complaining of pain in the sites corresponding to this referral pattern. The case history and the character of the of pain are important determinants in the diagnosis or clinical exclusion of cardiac referred pain. It is uncommon for a visceral pathology to be aggravated by provocative stimulation of the soma. A full cardiovascular examination is indicated to rule out cardiac referred pain.