ACUTE AND CHRONIC COCAINE EXPOSURE CAN PRODUCE MYOCARDIAL-ISCHEMIA AND INFARCTION IN YUCATAN SWINE

The purpose of this study was to determine whether the acute and chron ic administration of cocaine could induce myocardial infarction. Twent y-five minipigs were studied before and 4 months after balloon angiopl asty of the left anterior descending artery (LAD) and balloon denudati on of the left circumflex artery (LCx). Minipigs received cocaine in t he initial and in the 4-month study (0.1, 0.5, and 3 mg/kg i.v.). Mini pigs were randomized to group I (high-cholesterol diet + daily cocaine ; 500 mg i.m.; n = 8), group II (high-cholesterol diet + no i.v. cocai ne; n = 5), group III (chow diet + daily cocaine; 500 mg i.m.; n = 6), group IV (chow diet + no i.v. or i.m. cocaine; n = 6). In vivo, coron ary flow significantly decreased and vascular resistance significantly increased after the administration of cocaine. Histamine significantl y decreased the luminal diameters (LAD and LCx) in groups I, II, and I II. There were a total of five acute and 16 chronic infarctions among the three groups that received either short- or long-term cocaine; how ever, no infarct occurred in group IV. The combination of daily cocain e abuse with a cholesterol-rich diet enhanced coronary vasoreactivity in vivo and in vitro. We conclude that long-term or sporadic cocaine a buse can induce myocardial infarction.