Structural changes in the myocardium during diabetes-induced cardiomyopathy

Area of Science:

• Cardiology
• Endocrinology
• Pathology

Background:

• Diabetes mellitus (DM) affects over 250 million globally, with costs nearing £800 billion annually.
• DM complications include micro/macro-angiopathy and heart failure (HF), a leading cause of death in diabetics.
• Hyperglycaemia (HG) precedes diabetes-induced coronary artery disease and cardiomyopathy, contributing to HF.

Purpose of the Study:

• To review structural changes in the heart's myocardium and cardiomyocytes due to diabetes-induced hyperglycaemia (HG).
• To examine the impact of HG-induced oxidative stress on cardiac structures.
• To correlate these structural changes with the development of heart failure in diabetes.

Main Methods:

• Review of existing scientific literature on diabetes, hyperglycaemia, oxidative stress, and cardiac pathology.
• Analysis of ultrastructural changes in cardiomyocytes under chronic HG and oxidative stress.
• Correlation of observed structural alterations with clinical outcomes such as heart failure.

Main Results:

• Chronic HG and oxidative stress induce myocardial hypertrophy and fibrosis compared to control hearts.
• Ultrastructural analysis reveals swollen, reduced mitochondria, defective myofibrils, and intercalated discs in cardiomyocytes.
• Both type 1 and type 2 DM-induced HG contribute to myocardial fibrosis, mitochondriopathy, myocyte hypertrophy, and myofibril derangement.

Conclusions:

• Diabetes-induced hyperglycaemia and oxidative stress cause significant structural damage to the myocardium.
• These structural changes, including mitochondriopathy and myocyte hypertrophy, are key contributors to heart failure in diabetic patients.
• Effective management of hyperglycaemia is crucial to prevent irreversible cardiac structural damage and subsequent heart failure.