The most common shockable rhythms associated with cardiac arrest are pulseless ventricular tachycardia and ventricular fibrillation.
The most common underlying causes are ischemic heart disease and myocardial infarction. In some settings, cardiac arrest is the result of respiratory arrest triggered by opioid toxicity.
Presentation is usually sudden and manifests as loss of consciousness but can be preceded by chest pain or dyspnea.
Treatment is through implementing the algorithms for basic and advanced cardiac life support, depending on the provider’s level of training.
The overall survival from cardiac arrest, especially unwitnessed, is poor and, among early survivors, is fraught with complications of many organ systems due to ischemic injury (i.e., multisystem organ failure).
This topic covers cardiac arrest in adults. Sudden cardiac arrest is a sudden state of circulatory failure due to a loss of cardiac systolic function. It is the result of 4 specific cardiac rhythm disturbances: ventricular fibrillation, pulseless ventricular tachycardia (VT), pulseless electrical activity, and asystole. Torsades de pointes is a subgroup of polymorphic VT in patients with an underlying prolonged QT interval, sometimes related to hypomagnesemia.
History and exam
- coronary artery disease (CAD)
- left ventricular dysfunction
- hypertrophic cardiomyopathy (HCM)
- arrhythmogenic right ventricular dysplasia (ARVD)
- long QT syndrome (LQTS)
- medications that prolong the QT interval or cause electrolyte disturbances
- acute medical or surgical emergency
- illicit substances
- Brugada syndrome
- valvular heart disease
- history of eating disorders
Department of Family Medicine
University of Calgary
JW declares that he has no competing interests.
Professor and Department Head of Emergency Medicine
Cumming School of Medicine
University of Calgary
Alberta Health Services
EL declares that he has no competing interests.
Dr John Wink and Professor Eddy Lang would like to gratefully acknowledge Dr Amar Krishnaswamy and Dr Arman T. Askari, previous contributors to this topic.
Professor of Medicine
Division of Cardiology
University of California
VM declares that he has no competing interests.
NYU Department of Medicine (Cardiology)
Leon H Charney Heart Rhythm Center and New York University
AA declares that he has no competing interests.
Honorary Clinical Senior Lecturer/Consultant
Department of Cardiology
Imperial College London
MFP declares that he has no competing interests.
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