Sudden Cardiac Deaths—WHO Says They Are Always Arrhythmic?

Sudden cardiac death (SCD) is considered a major cause of worldwide mortality, and coronary artery disease (CAD) has long been thought to underlie most SCDs on the basis of historical studies of selected sudden deaths referred for autopsy.¹ More than a decade ago, society guidelines incorporated findings of mortality benefit for primary-prevention implantable cardioverter defibrillators (ICDs) in patients with ischemic heart disease and left ventricular ejection fractions (EFs) of 35% or less, yet most SCDs in the population affected by ischemic conditions have unknown EFs or EFs above this threshold.² Thus, the search has been ongoing for criteria or clinical factors to distinguish which patients with CAD but without severe systolic dysfunction might benefit from prophylactic ICD implantation to prevent SCD.