Cocaine-Associated AMI

Management of Cocaine-Associated Chest Pain and MI
The most important differences from management of non–cocaine-associated chest pain and MI are use of benzodiazepines and avoidance of beta-blockers for patients with hypertension and tachycardia.

The American Heart Association (AHA) has published a review of recent literature and recommendations for management of patients with cocaine-associated chest pain and myocardial infarction. Cocaine use leads to increased cardiac demand and accelerated atherosclerosis and coronary vasospasm. The AHA recommendations indicate that treatment of cocaine-associated myocardial ischemia differs in several important ways from treatment of non–cocaine-associated ischemia.

• Aspirin and nitrates continue to be strongly recommended as they are for non–cocaine-associated acute coronary syndrome (ACS), but β-blockers (including agents with mixed -adrenergic antagonist effects, such as labetolol) are considered contraindicated, despite a relatively weak evidence base. Theoretically, β-blockade might induce or worsen hypertension and vasospasm.
• If cocaine intoxication is suspected, benzodiazepines are recommended as the primary treatment for anxiety, tachycardia, and hypertension.
• Calcium channel blockers are not recommended. Some evidence from studies of patients with non–cocaine-associated ACS suggests that calcium channel blockers increase mortality rates when used as a first-line agent for control of hypertension.
• Early percutaneous coronary intervention is particularly preferred over fibrinolysis in patients with cocaine-associated MI because of increased risk for intracranial hemorrhage after administration of fibrinolytic agents in cocaine users.

Comment:
Early aggressive treatment continues to be the mainstay of therapy for patients with suspected ACS. However, treatment for cocaine-associated ACS differs in several important ways from treatment for non–cocaine-associated ACS. Clarifying whether cocaine was recently used is important before administering β-blockers.

— Aaron E. Bair, MD, MSc, FAAEM, FACEP
Published in Journal Watch Emergency Medicine May 23, 2008

Citation(s): McCord J et al. Management of cocaine-associated chest pain and myocardial infarction: A scientific statement from the American Heart Association Acute Cardiac Care Committee of the Council on Clinical Cardiology. Circulation 2008 Apr 8; 117:1897.