CHICAGO — Administering a combination of glucose, insulin and potassium cut the risk for death and cardiac arrest in half when treatment was given immediately after diagnosis of acute coronary syndrome, according to data from the IMMEDIATE trial.
The randomized, double blind, placebo-controlled trial tested administration of combination glucose, insulin and potassium (GIK) initiated by paramedics in the home or during hospital transport, for example, confirmed by ED physicians for continued use in hospital for a total of 12 hours.
The primary endpoint of progression of ACS to MI within 24 hours was not different between patients assigned GIK compared with those assigned placebo (48.7% vs. 52.6%). Thirty-day mortality was higher in the placebo group (4% vs. 6%), but this finding did not reach statistical significance. Fewer patients in the GIK group experienced the composite of cardiac arrest or in-hospital mortality compared with the placebo group (4.4% vs. 8.7%; P=.01).
Better outcomes were observed among patients with ST-segment elevation (GIK, n=163; placebo, n=194). Fourteen percent of the placebo group experienced the composite outcome of cardiac arrest or mortality compared with 6% of the GIK group. Progression to MI and 30-day mortality were also lower in these patients assigned GIK.
Although GIK administration did not prevent infarction, early treatment was associated with greater reductions in infarct size compared with placebo (3% of left ventricular mass vs. 12% of left ventricular mass).
Serious adverse events occurred in 6.8% of the GIK group vs. 8.9% of the placebo group.
The data were presented at the American College of Cardiology’s 61st Scientific Sessions.
“We conclude from [these results] that one way to administer GIK in patients of this sort is in the field in the first 1 to 2 hours,” Harry P. Selker, MD, MSPH, executive director of the Institute for Clinical Research Health Policy Studies at Tufts Medical Center, said at a press conference.
The Immediate Myocardial Metabolic Enhancement During Initial Assessment and Treatment in Emergency Care (IMMEDIATE) trial included 911 patients. Patients were randomly assigned to very early use of GIK 30% glucose, 50 U insulin, 80 mEq/L potassium at 1.5 mL/kg/hour) or similar-looking 5% glucose placebo. The researchers evaluated three cohorts: an intention-to-treat group, patients presenting with ST-segment elevation MI or ST-segment elevation in their homes and those in whom the researchers conducted additional biomedical tests. Researchers provided instruments such as electrocardiographs to help paramedics determine whether a patient required treatment.
During the press conference, Selker said GIK received attention in the past because of data that it could prevent MI in animals. Studies in humans, however, indicated little benefit. An added bonus is that GIK is relatively inexpensive, approximately $50, he noted. – by Melissa Foster
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Disclosure:The study was funded by the NIH’s National Heart, Lung and Blood Institute.
As Dr. Selker pointed out, there have been 11 previous trials on GIK and the data have been negative. So, we are not going to suddenly discard those data and only consider [ILLUMINATE]. I think the researchers probably will get funding for a larger study, and if the physiology makes sense and it turns out that we can ultimately reduce mortality with this treatment that would certainly be a good thing. Overall, I don’t think anyone should take the results of this study and start administering GIK to everyone, because that would not be reasonable.
– William Weintraub, MD
Cardiology Today Editorial Board member