Glucose levels may indicate severity of heart attack damage

High glucose levels could serve as a biomarker indicating a worse outcome in patients who have experienced their first acute myocardial infarction, according to researchers in Brazil.

The study demonstrated that glycaemic variability, particularly glycaemic delta, is associated with the size of the infarction and a reduction in left ventricular ejection fraction (LVEF). LVEF shows the strength of the heart’s contraction; if it is reduced, heart failure may result.

To evaluate muscle loss and heart damage, a magnetic resonance imaging (MRI) scan was performed 30 days after the heart attack. Based on a sample of 244 individuals treated at Hospital São Paulo, the study concluded that higher glycaemic delta is associated with worse myocardial damage, regardless of whether the patient has diabetes.

The study was conducted by the Federal University of São Paulo (UNIFESP), the Dante Pazzanese Institute, and the Albert Einstein Jewish Brazilian Hospital – as well as from Laval University in Canada. The results of the study were published in the journal Diabetology & Metabolic Syndrome.

‘The findings surprised us, and based on our literature review, they were unprecedented. They open a number of doors for us to further study the pathophysiology of patients who have had a myocardial infarction,’ said Prof Henrique Tria Bianco, a cardiologists at UNIFESP.

Professor Francisco Antonio Fonseca of São Paulo Research Foundation said the findings suggest glucose could be used as a biomarker. ‘Through a simple, inexpensive test that almost all patients do, which is glycated haemoglobin for hospital admission, we end up with an easy-to-obtain biomarker with important implications,’ he said.

‘In other words, patients with a higher delta will have greater infarct mass and will need myocardial protection, both in relation to blood glucose and, for example, the use of beta-blockers, to improve their prognosis.’