Improvement in Diagnosis of Sudden Cardiac Death

Sudden death (SD) is often the first clinical manifestation of an underlying disease in previously asymptomatic, apparently “healthy” subjects. Various criteria have been used to define sudden cardiac arrest and sudden cardiac death in the medical literature. The 2006 American College of Cardiology/American Heart Association/Heart Rhythm Society (ACC/AHA/HRS Writing Committee to establish data standards for electrophysiology) included definitions to guide documentation in research and clinical practice. “[Sudden] cardiac arrest is the sudden cessation of cardiac activity so that the victim becomes unresponsive, with no normal breathing and no signs of circulation. If corrective measures are not taken rapidly, this condition progresses to sudden death. Cardiac arrest should be used to signify an event as described above, that is reversed, usually by CPR and/or defibrillation or cardioversion, or cardiac pacing. Sudden cardiac death should not be used to describe events that are not fatal.” Correct identification of future SCD victims is especially important as there is an effective treatment, namely, defibrillation via an external or internal (implanted) defibrillator. Currently, the commonly used SCD risk score based on left ventricular ejection fraction can only predict some cardiac arrest events. There is an urgent need for more effective and reliable SCD risk early warning methods. The rapid development of ECG signals, genetic markers, and a combination of multiple index risk scoring models, including the foregoing two, have opened new paths for SCD early warning diagnosis.