Although the long-term survival of patients suffering from coronary spasm is usually excellent, serious complications can develop, such as disabling pain, myocardial infarction, ventricular tachyarrhythmias, atrioventricular block and sudden cardiac death. A 40-year-old man who had intractable chest pain from coronary artery spasm suffered ventricular fibrillation and an acute anterior myocardial infarction upon first admission. The patient underwent a coronary angiogram, which revealed a spontaneous focal spasm at the proximal left anterior descending coronary artery (LAD). He was treated by the combination of nitrate and calcium channel blocker, but continued to complain of severe chest pain despite intensive medical therapy and he had to be treated in the emergency room 5 times during an 8-month follow-up period. An ergonovine coronary angiogram was performed and an intracoronary ultrasound examination, which revealed a focal spasm at the same site of the proximal LAD with a small amount of localized eccentric atheromatous plaque. A coronary artery stent was placed in the proximal LAD and his symptoms resolved. A follow-up coronary angiogram was performed 3 years after stenting and the stent remained patent without any in-stent restenosis or spasm.
Background Aspirin, one of the antiplatelet agents, improves the survival rate after myocardial infarction. This beneficial effect is known to be obtained in part by the antiarrhythmic action of aspirin. It is not known whether other antiplatelet agents have such effects. This study was performed to compare the effects of aspirin, ticlopidine, and abciximab platelet glycoprotein IIb/IIIa receptor antagonist on the ischemia-induced arrhythmias with a rat model of cardiac regional ischemia. Methods Experiments were performed in 4 groups of rats. The 4 groups were as follows control, n 10 aspirin-pretreated, 300 mg/kg po for 1 week ticlopidine-pretreated, 200 mg/kg po for 1 wk abciximab-pretreated, 2 mg/kg iv 10 20 minutes before experiment. The electrocardiogram and blood pressure were recorded during 20 minutes. The time to the onset of ST-segment elevation and ventricular tachyarrhythmias, frequency and incidence of ventricular tachyarrhythmias, and death rate were assessed during acute myocardial ischemia induced by ligation of proximal left anterior descending coronary artery in anesthetized rats. Results Platelet aggregations to ADP were significantly lower in aspirin 42.8% , ticlopidine 43.8% , and abciximab group 34.0% than in control group 66.4% . The frequencies of sustained ventricular tachycardia VT were 6.8 3.6 in control, 3.6 3.8 aspirin, 4.7 3.7 ticlopidine, and 1.4 2.5 abciximab group. The frequency of sustained VT in the abciximab group was significantly lower than in control group. The incidences of ventricular arrhythmias for 20 min were 10/10 for VT and 8/10 for ventricular fibrillation VF in control group, 7/10 for VT and 3/10 for VF in aspirin group, 10/10 for VT and 3/10 for VF in ticlopidine group, and 5/10 for VT and 4/10 for VF in abciximab group. The incidences of cardiac death during 20 min were 8/10 in control group, 4/10 in aspirin group, 2/10 in ticlopidine group and 5/10 in abciximab group. The incidence of VT in the abciximab group was significantly lower than in control group, incidences of VF in the aspirin and ticlopidine groups were significantly lower than in control group, and death rate in ticlopidine group was significantly lower than in
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.