The role of the sympathetic nervous system in sudden cardiac death

Sudden cardiac death (SCD) is a complex disease and represents one of the largest burdens to health care worldwide. It is known to be associated with various disease conditions, including but not limited to, cardiac arrhythmias, coronary artery disease, cardiomyopathies, valvular disorders and diabetes. Although much work is left to be done in uncovering the underlying mechanisms of SCD, response of the sympathetic nervous system to a prolonged stressful stimulus and the release of excessive amounts of catecholamines and their subsequent oxidation has potential to explain the regularly observed etiologies and provide a unified mechanism for the occurrence of SCD. Current possible treatments for patients at risk for SCD range from the implantation of cardioverter defibrillators to pharmaceutical interventions including anti-arrhythmic drugs, antiplatelet agents and β-adrenoceptor blockers. However, there are some studies suggesting the merit of prophylactic treatment using antioxidants such as vitamins A, C and E in preventing arrhythmias and consequent SCD. Overstimulation of the sympathetic stress response may result in SCD, and combination therapy with antioxidants and β-adrenoceptor blockers may be suitable for its prevention.