Risk stratification of high-risk post-myocardial infarction patients has limited value, as 70% to 85% of these patients will not experience a sustained ventricular tachyarrhythmia over several years.
What are the effective strategies for predicting and preventing sudden cardiac death in high-risk patients?
Aggressive treatment and screening are mandatory for high-risk patients to prevent sudden cardiac death, with ICDs, beta-blockers, and specific antiarrhythmics showing varying benefits.
Sudden cardiac death usually occurs secondary to a ventricular tachyarrhythmia. Even under ideal circumstances only 20% of patients who have an out-of-hospital cardiac arrest survive to hospital discharge. Therefore, aggressive treatment and screening of high-risk patients are mandatory to improve survival rates. Risk stratification of high-risk patients, such as the post-myocardial infarction (MI) population, has been of limited value. Between 70% and 85% of "high-risk" post-MI patients, as defined by these screening tests, will not have a sustained ventricular tachyarrhythmia over several years of follow-up. The use of beta-blockers and possibly amiodarone may have some benefit in reducing mortality in high-risk patients after an MI. Several ongoing trials are studying the use of serial drug testing, amiodarone, and implantable cardioverter-defibrillators in reducing the incidence of sudden cardiac death in patients with potentially lethal ventricular arrhythmias. Although implantable cardioverter-defibrillators appear to be superior to antiarrhythmic drugs in reducing sudden cardiac death, total mortality may not be altered. In sustained ventricular tachyarrhythmias, sotalol and amiodarone appear to be superior to other drugs in preventing arrhythmia recurrence. Ongoing trials, such as the Antiarrhythmic Drug versus Implantable Device (AVID) trial may define the best strategy in these high-risk patients.
Gilman et al. (1994) conducted a review in Sudden cardiac death. Antiarrhythmic drugs and implantable cardioverter-defibrillators was evaluated. Risk stratification of high-risk post-myocardial infarction patients has limited value, as 70% to 85% of these patients will not experience a sustained ventricular tachyarrhythmia over several years.