PET Imaging of Cardiac Sympathetic Innervation Predicts Sudden Cardiac Death in Ischemic Cardiomyopathy

According to the American Heart Association, approximately 10,000 implantable cardiac defibrillators (ICDs) are implanted each month. Most of these are for primary prevention, meaning that they are implanted in patients who have never before had cardiac arrest but are at increased risk for a lethal cardiac arrhythmia (ventricular tachycardia or ventricular fibrillation). Left-ventricular ejection fraction (LVEF) remains essentially the only parameter used to estimate risk and allocate patients for ICD implantation. Patients with an LVEF ≤35% despite optimal medical therapy are typically referred for ICD implantation. Most patients who receive ICD implantation for primary prevention never require defibrillation afterward; and despite being at less risk relative to patients with an LVEF ≤35%, patients with an LVEF >35% account for the largest number of sudden cardiac deaths. Objective: To test the hypothesis that inhomogeneity in myocardial sympathetic innervation as assessed wit more...