Author + information
- Received July 13, 2016
- Revision received August 23, 2016
- Accepted August 25, 2016
- Published online December 12, 2016.
- Karl B. Kern, MDa,∗ (, )
- Joseph M. Hanna, MDa,
- Hayley N. Younga,
- Carl J. Ellingson, BSa,
- Joshua J. White, BSa,
- Brian Heller, MSa,
- Uday Illindala, MSb,
- Chiu-Hsieh Hsu, PhDa and
- Mathias Zuercher, MDa,c
- aUniversity of Arizona Sarver Heart Center, Tucson, Arizona
- bZoll Circulation, San Jose, California
- cUniversity of Basel, Basel, Switzerland
- ↵∗Reprint requests and correspondence:
Dr. Karl B. Kern, Sarver Heart Center, University of Arizona, 1501 North Campbell Avenue, Tucson, Arizona 85724.
Objectives The aim of this study was to test the hypothesis that hypothermia and early reperfusion are synergistic for limiting infarct size when an acutely occluded coronary is associated with cardiac arrest.
Background Cohort studies have shown that 1 in 4 post–cardiac arrest patients without ST-segment elevation has an acutely occluded coronary artery. However, many interventional cardiologists remain unconvinced that immediate coronary angiography is needed in these patients.
Methods Thirty-two swine (mean weight 35 ± 5 kg) were randomly assigned to 1 of the following 4 treatment groups: group A, hypothermia and reperfusion; group B, hypothermia and no reperfusion; group C, no hypothermia and reperfusion; and group D, no hypothermia and no reperfusion. The left anterior descending coronary artery was occluded with an intracoronary balloon, and ventricular fibrillation was electrically induced. Cardiopulmonary resuscitation was begun after 4 min of cardiac arrest. Defibrillation was attempted after 2 min of cardiopulmonary resuscitation. Resuscitated animals randomized to hypothermia were rapidly cooled to 34°C, whereas those randomized to reperfusion had such after 45 min of left anterior descending coronary artery occlusion.
Results At 4 h, myocardial infarct size was calculated. Group A had the smallest infarct size at 16.1 ± 19.6% (p < 0.05). Group C had an intermediate infarct size at 29.5 ± 20.2%, whereas groups B and D had the largest infarct sizes at 41.5 ± 15.5% and 41.1 ± 15.0%, respectively.
Conclusions Acute coronary occlusion is often associated with cardiac arrest, so treatment of resuscitated patients should include early coronary angiography for potential emergent reperfusion, while providing hypothermia for both brain and myocardial protection. Providing only early hypothermia, while delaying coronary angiography, is not optimal.
This work was funded by the Steven M. Gootter Foundation and Zoll Circulation. Dr. Kern is a member of the science advisory board for Zoll Medical. Dr. Illindala was an employee of Zoll Circulation during this study. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
- Received July 13, 2016.
- Revision received August 23, 2016.
- Accepted August 25, 2016.
- 2016 American College of Cardiology Foundation