Glucose Level Fluctuations Linked to Heart Attack Severity

Recent research from Brazilian scientists has unveiled a significant correlation between fluctuations in glucose levels and the severity of damage caused by heart attacks. This discovery could pave the way for improved patient outcomes following acute myocardial infarctions.

The study focused on glycemic variability, particularly glycemic delta, which was found to be associated with the extent of heart tissue damage and a decrease in left ventricular ejection fraction (LVEF). LVEF is an important measure of heart function, indicating the heart's ability to pump blood effectively, and its reduction can lead to heart failure.

Conducted at Hospital São Paulo, the research involved 244 participants who experienced their first acute myocardial infarction, regardless of their diabetes status. The key metric, glycemic delta, is determined by subtracting the estimated average blood glucose level, derived from glycated hemoglobin tests, from the blood glucose level recorded upon hospital admission.

To assess heart damage and muscle loss, participants underwent magnetic resonance imaging (MRI) 30 days post-heart attack. The collaborative study included experts from the Federal University of São Paulo (UNIFESP), the Dante Pazzanese Institute, and the Albert Einstein Jewish Brazilian Hospital, alongside researchers from Laval University in Canada. Findings from this research were published in the journal Diabetology & Metabolic Syndrome.

One of the researchers indicated that these findings were unexpected and represent a novel contribution to understanding the pathophysiology of myocardial infarction. The study suggests that a routine, cost-effective test--namely the glycated hemoglobin test--can provide valuable biomarkers for predicting myocardial damage. Patients exhibiting a higher glycemic delta are likely to experience more severe heart damage and may require more intensive myocardial protection measures during treatment.

Acute myocardial infarction, commonly known as a heart attack, stands as the leading cause of mortality in Brazil, with estimates indicating between 300,000 and 400,000 cases annually. This condition involves the death of heart muscle cells due to blood clots that obstruct blood flow, resulting in symptoms such as chest pain that may radiate to other areas of the body, sweating, and shortness of breath. Prompt treatment is crucial for reducing mortality risk.

The study's cohort consisted of patients over 18 years of age who received fibrinolytics--medications aimed at dissolving the blood clots--within six hours of symptom onset. Initially treated within Brazil's national public health network, these patients were subsequently transferred to Hospital São Paulo. Participants varied in their diabetic status, including individuals with diabetes, prediabetes, and those without any glucose metabolism disorders.

The current standard treatment for myocardial infarction typically involves primary angioplasty and the initiation of fibrinolysis. Among those receiving pharmacoinvasive treatment, higher glycemic delta values were correlated with larger infarct sizes and lower left ventricular ejection fractions.

Researchers emphasized the importance of validating these findings in other populations to better understand the implications for patient health. Future research is expected to delve into the molecular pathways and cellular mechanisms that contribute to these findings, as well as explore targeted therapeutic approaches to improve outcomes for high-risk individuals. Additionally, mortality data analysis related to the study is forthcoming.