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CHAPTER SUMMARY AND CENTRAL ILLUSTRATION
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Chapter Summary
This chapter provides a structural and practical discussion of sudden cardiac death (SCD), acute resuscitation, and postresuscitation care. The various etiologies of SCD include arrhythmias, coronary disease, genetic electrical syndromes, and structural causes. SCD can strike individuals in the broad population, as well as special populations at risk, including women, underrepresented minorities, and athletes. Paradoxically, a substantial minority of cases classified as SCD are noncardiac and span neurological, respiratory, and other causes. Currently, risk stratification for SCD is suboptimal and future avenues for improved mechanism-based prediction are highlighted. Notably, in-hospital SCD is associated with better prognosis than out-of-hospital SCD. Effective early response is critical and shares similarities for both types of arrest. The chapter details basic and cardiopulmonary resuscitation, including current emergency pharmacological management and coronary catheterization. Postresuscitation care focuses on preserving the brain—including via therapeutic temperature management (induced hypothermia)—neurological recovery, as well as cardiopulmonary management. The ethics of end-of-life management and withdrawal of resuscitation are also emphasized.
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DEFINITION, EPIDEMIOLOGY, AND HISTORICAL CONSIDERATIONS
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Sudden cardiac arrest (SCA) is defined by the World Health Organization (WHO) as a sudden unexpected death either within 1 hour of symptom onset if witnessed, or within 24 hours of having been observed alive and symptom free if unwitnessed.1 If not successfully resuscitated, individuals with SCA progress rapidly to sudden cardiac death (SCD).
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The first successful resuscitation from out-of-hospital SCA was reported in 1956, in a male physician with indigestion who was diagnosed with myocardial infarction and discharged but then collapsed outside the hospital.2 He was resuscitated by using emergency thoracotomy, cardiac massage, and defibrillation. At about that time, Gurvich in the Soviet Union reported external defibrillation in animal studies and Zoll et al. in the United States reported defibrillation in patients. These studies occurred at a time in history when society was beginning to experience electrocution accidents related to electrification.2 The subsequent success of external defibrillation for ventricular fibrillation ushered in the era of coronary care units and the model of rapid defibrillation for SCA.
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SCD is a leading cause of death worldwide and accounts for 180,000 to 450,000 deaths annually in the United States.3 SCD may be a patient’s first clinical presentation, but is also common in patients with known cardiac disease. The incidence of SCD has risen during crises such as the 9/11 attacks,4 and during the COVID-19 pandemic5 in parallel with a drop in admissions for acute coronary syndrome.6 SCD is less common in women than men (42% vs 58% of victims),3 but in Black populations its incidence is double that in White populations7 and it occurs at a younger age8 (Fig. 63–1A). The prevalence of SCD exhibits strong ...