ABSTRACT

BACKGROUND - Experimental trials suggest improved outcome by mild therapeutic hypothermia for cardiogenic shock following acute myocardial infarction. The objective of this study was to investigate 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 intervention 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 TRAIL REGISTRATION - URL: www.clinicaltrials.gov Unique Identifier: NCT01890317.