Safety of therapeutic hypothermia combined with primary percutaneous coronary intervention after out-of-hospital cardiac arrest

Background: The safety of therapeutic hypothermia combined with percutaneous coronary intervention (PCI) after out-of-hospital cardiac arrest has been challenged after reports of high risk of stent thrombosis. Methods: We searched the Western Denmark Heart Registry to identify patients with an acute coronary angiography due to out-of-hospital cardiac arrest performed at our institution between September 2010 and September 2013. We identified 68 unconscious patients, who were resuscitated after out-of-hospital cardiac arrest and underwent acute PCI with stent implantation and immediate therapeutic hypothermia, and followed these for 30 days. Target temperature of 32-34 degrees C was achieved by either an invasive or a non-invasive cooling system. Results: All patients had elevated myocardial biomarkers and 37 patients had ST-segment elevation myocardial infarction. Bare metal stents were implanted in 14 and drug-eluting stents in 54 patients. All patients received antithrombotic treatment with a standard loading dose of 300 mg acetylsalicylic acid and 10,000 units heparin intravenously prior PCI. Clopidogrel or ticagrelor was administered orally through a gastric tube immediately after PCI. During the procedure abciximab or bivalirudin was administered in 44 patients. Electrocardiographic and clinical signs of stent thrombosis were found in one patient. Conclusions: We observed one stent thrombosis in this cohort of 68 consecutive patients with out-of-hospital cardiac arrest who were treated with PCI and therapeutic hypothermia. This suggests that PCI with stent implantation can be performed with acceptable safety in these patients.