Glucose-insulin-potassium infusion as adjunctive therapy in myocardial infarction: Current evidence and potential mechanisms

Background. In ST-elevation myocardial infarction (STEMI) there is conflicting evidence that mortality, morbidity and infarct size is reduced by therapies influencing myocardial metabolism, such as infusion of glucose-insulin-potassium (GIK). Several clinical trials with GIK have already provided insight into the magnitude of this effect. The aim of this article was to review randomized trials on adjunctive GIK infusion in STEMI. Methods. Randomized trials comparing GIK with placebo or untreated controls in patients with STEMI were identified by electronic and manual searches. A systematic analysis of all data was performed, with regard to inclusion criteria, dose of GIK and additional use of reperfusion therapy. Thirteen trials, involving 4992 patients, were included. Results. Overall, hospital mortality was 10.8% after GIK compared to 12.9% in controls (p = 0.02). GIK infusions were in particular effective when a high dose was used and if given as an adjunct to reperfusion therapy. In patients with heart failure on admission, GIK may have worse effects. In all analyzed trials, GIK infusion caused only mild adverse effects, although fluid overload may be a problem in certain patients. Conclusions. GIK may reduce mortality in patients with STEMI, particularly if a high dose is used and when GIK is administered as an adjunct to reperfusion therapy. However, all studies had a relative small sample size and additional large randomized trials are certainly needed before a definite conclusion can be made. The limited evidence currently available does not warrant GIK therapy to be applied in patients at the present time.