Collection of signs and symptoms caused by coronary artery occlusion. 3 clinical manifestations.

Mechanism of Cardiac Pain

ischemia → excitement of chemo/mechanoreceptors → adenosine/bradykinin release → excitement of sympathetic and vagal afferent fibres → sympathetic afferent impulses converge with impulses from somatic thoracic structures → chest/ referred pain

Clinical Features

• Severe sudden onset chest pain
• Sweating, radiation of pain to arm and jaw
• Anxiety, restlessness, nausea and vomiting
• Signs of haemodynamic compromise – hypotension, pulmonary oedema, tachycardia, tachypnoea

<aside> 💡 Diabetics may be painless due to autonomic neuropathy affecting sensory innervation of the heart

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<aside> 💡 Women are more likely to experience nausea and vomiting, cold/clammy skin back pain fatigue and SOB without chest pain.

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Aetiology/Pathology

• STEMI: caused by complete occlusion of coronary artery, cutting off blood supply to full thickness of myocardium
• NSTEMI: a partial occlusion of a coronary artery that only causes ischemia to the inner layer of the heart. This results in subendocardial infarction
• Unstable Angina: partial occlusion of coronary vessels, leading to reduced blood supply to cardiac myocytes leading to ischemic symptoms (even at rest). The blockage is relieved prior to cellular damage