differential diagnosis of chest pain

Question 1

how do autonomic innervation and visceral afferent nerves reach the heart?

Answer 1

• via the central plexus

Question 2

how do sympathetic nerve fibres get from the CNS to the organs?

Answer 2

• presynaptic sympa fibres form the brain travel inferiorly within the spinal cord tracts and then exit the spinal cord in one of T1-L2/3 spinal nerves (thoracolumbar) and then either
  1. go into ganglion of that level and synpase
  2. travel superiorly/inferiorly in the sympa chain to another ganglion and synapse

Question 3

how do parasympathetic signals from the CNS reach the organs?

Answer 3

• CN III, IX, X

- CN X (vagus) = presynaptic para fibres in vagus nevre then synapse onto postsynaptic neurones

Question 4

what are the potential sources of chest pain?

Answer 4

• somatic = muscular, joint, bon, intervertebral disc
• sharp, stabbing, well localised
• visceral = heart and great vessles, trachea, oeophagus
• dull, aching, poorly localised

Question 5

what happens at the postcentral gyrus of the partetial lobes (somatosensory)?

Answer 5

• APs arriving here bring body wall (somatic) sensations into consciousness

Question 6

what happens at the precentral gyrus of the frontal lobes (somatomotor)?

Answer 6

• APs originating here bring about contractions of body walls (somatic) skeletal muscle

Question 7

what is herpes zoster (shingles)?

Answer 7

• sharp pain
• in posterior root ganglion
• pain precedes blisters
• in T4/T5 = central chest pain