1. Ion channel dysfunction: - Insulin resistance can alter the expression and function of cardiac ion channels, particularly potassium channels. - This can lead to prolonged action potential duration and QT interval, increasing the risk of arrhythmias.
2. Autonomic nervous system imbalance: - Insulin resistance is associated with increased sympathetic activity and reduced parasympathetic tone. - This imbalance can affect heart rate variability and increase susceptibility to arrhythmias.
3. Fibrosis and remodeling: - Insulin resistance promotes cardiac fibrosis and structural remodeling. - These changes can disrupt normal conduction pathways, potentially leading to re-entry circuits and arrhythmias.
4. Calcium handling abnormalities: - Insulin resistance can impair intracellular calcium homeostasis in cardiomyocytes. - Altered calcium handling can lead to delayed afterdepolarizations and triggered activity, promoting arrhythmias.
5. Oxidative stress: - Increased oxidative stress associated with insulin resistance can damage cardiac tissues, including conduction system components. - This may lead to conduction abnormalities and increased arrhythmia risk.
6. Microvascular dysfunction: - Insulin resistance can impair coronary microvascular function. - Reduced blood flow to the conduction system may contribute to conduction disturbances.
7. Metabolic disturbances: - Altered substrate metabolism in insulin-resistant states can affect the energy supply to the conduction system. - This may impact the function of pacemaker cells and conduction velocities.
These mechanisms collectively contribute to an increased risk of various cardiac arrhythmias and conduction disturbances in insulin-resistant individuals, including:
