Hyperglycemia in acute coronary syndromes: from mechanisms to prognostic implications:

Hyperglycemia is a frequent condition in patients with acute coronary syndromes (ACS). Hyperglycemia during ACS is caused by an inflammatory and adrenergic response to ischemic stress, when catecholamines are released and glycogenolysis induced. Although the involved pathophysiological mechanisms have not yet been fully elucidated, it is believed that hyperglycemia is associated with an increase in free fat acids (which induce cardiac arrhythmias), insulin resistance, chemical inactivation of nitric oxide and the production of oxygen reactive species (with consequent microvascular and endothelial dysfunction), a prothrombotic state, and vascular inflammation. It is also related to myocardial metabolic disorders, leading to thrombosis, extension of the damaged area, reduced collateral circulation, and ischemic preconditioning. In the last few years, several observational studies demonstrated that hyperglycemia in ACS is a powerful predictor of survival, increasing the risk of immediate and long-term compli...