Mild Hypothermia in Cardiogenic Shock Complicating Myocardial Infarction – The Randomized SHOCK-COOL Trial [Original Research Article]

Background—Experimental trials suggest improved outcome by mild therapeutic hypothermia for cardiogenic shock following acute myocardial infarction. The objective of this study was to inves-tigate hemodynamic effects of mild therapeutic hypothermia in patients with cardiogenic shock complicating acute myocardial infarction.Methods—Patients (n=40) with cardiogenic shock undergoing primary percutaneous coronary in-tervention without classical indication for mild therapeutic hypothermia underwent randomization in a 1:1 fashion to mild therapeutic hypothermia for 24 h or control. The primary endpoint was cardiac power index at 24 h; secondary endpoints included other hemodynamic parameters as well as serial measurements of arterial lactate. Results—No relevant differences were observed for the primary endpoint cardiac power index at 24 h (mild therapeutic hypothermia vs. control: 0.41 [interquartile range 0.31-0.52] vs. 0.36 [inter-quartile range 0.31-0.48] W/m2; p=0.50, median difference -0.025 [95% confidence interval -0.12 to 0.06 W/m2]). Similarly, all other hemodynamic measurements were not statistically different. Arterial lactate levels at 6, 8 and 10 hours were significantly higher in patients in the MTH group with a slower decline (p for interaction 0.03). There were no differences in 30-day mortality: (60 vs. 50%, hazard ratio 1.27 [95% confidence interval 0.55-2.94]; p=0.55).Conclusions—In this randomized trial mild therapeutic hypothermia failed to show a substantial beneficial effect in patients with cardiogenic shock after acute myocardial infarction on cardiac power index at 24 h.Clinical Trial Registration—URL: www.clinicaltrials.gov Unique Identifier: NCT01890317