The most common electrophysiologic mechanisms leading to SCD are tachyarrhythmias such as ventricular fibrillation (VF) or ventricular tachycardia (VT). Interruption of tachyarrhythmias, using either an automatic external defibrillator (AED) or an implantable cardioverter defibrillator (ICD), has been shown to be an effective treatment for VF and VT. The implantable defibrillator has become the central therapeutic factor in the prevention and treatment of sudden cardiac death.
Patients with tachyarrhythmias, especially VT, carry the best overall prognosis among patients with sudden cardiac arrest (SCA).Out of 1204 cases of out-of-hospital sudden deaths reported to the coroner, the underlying causes were acute myocardial infarction in 31%, coronary artery disease in 26%, hypertensive heart diseases in 14%, ruptured aortic aneurysm in 6%, cardiomyopathies in 5%, other cardiovascular diseases in 7%, and non-cardiovascular causes in 11%.
In less than 1% of these cases, no structural abnormality could be identified by postmortem examination.CPR: Immediate cardiopulmonary resuscitation (CPR) is critical to treating sudden cardiac arrest. By maintaining a flow of oxygen-rich blood to the body's vital organs, CPR can provide a vital link until more advanced emergency care is available. Ongoing Research is being done at cardiac centres.