Cocaine and Chest Pain

Epidemiology

• ~450,000 ED visits per year for cocaine related complaints
• 0.7-6% of patients with CP and cocaine are having an MI

Mechanism of Action

• Cocaine blocks reuptake of norepinephrine + dopamine at adrenergic synapse leading to accumulation of catecholamines and thus sympathomimetic effects
• Vasoconstriction, increased cardiac contractility, increased HR, increased SBP/DBP/MAP
• Cocaine can cause coronary vasospasm (angina) and may increase coronary atherosclerosis and thrombosis (infarction)
• Initial cardiac effects are rapid (~1 hour) but metabolites may continue to cause symptoms for up to 4 days

Detection

• Urine cocaine test checks for benzoylecgonine (cocaine metabolite) and is specific (95%) and sensitive (99%)
• Eliminated from urine in 12 hours but may last up to 72 hours in heavy users

Treatment

• Consider other causes of chest pain (i.e. aortic dissection, pulmonary HTN, "crack lung")
• Treat agitation and cardiac effects with Benzodiazepines
• Treat HTN with Nitroglycerin, Nitroprusside, Phentolamine
• Treat Tachyarrhythmias with bicarbonate, lidocaine, or amiodarone
• Avoid beta-blockers (may worsen coronary vasospasm)

Source: http://journals.lww.com/em-news/blog/spontaneouscirculation/Pages/default.aspx
Source: http://circ.ahajournals.org/content/117/14/1897.full.pdf+html