Emergency pretreatment for contrast allergy before direct percutaneous coronary intervention for ST-elevation myocardial infarction.

Patients with previous adverse contrast reactions occasionally present with ST-segment elevation myocardial infarction. Whether they can undergo catheterization safely using current contrast and medications is unknown. We reviewed catheterization laboratory records of all 501 patients (January 2005 to December 2006) presenting with ST-segment elevation myocardial infarction who underwent emergency coronary angiography. Six patients (1.2%) reported a previous contrast reaction including rash, acute bronchospasm, or anaphylaxis. All received a combination of intravenous steroids and H1 and H2 blockers in the emergency department or catheterization laboratory before catheterization. None of these had complications or evidence of allergy in any patient. In conclusion, some patients with previous contrast reaction may undergo emergency catheterization without adverse consequences, although the safety of this approach has not been proved.