Last reviewed: 17 Mar 2025
Last updated: 24 Nov 2023
Summary
Definition
History and exam
Key diagnostic factors
- history of coronary artery disease
- history of hypertrophic cardiomyopathy
- history of idiopathic dilated cardiomyopathy
- presence of other known causes
- asymptomatic presentation
- tachycardia
Risk factors
- coronary artery disease
- left ventricular systolic dysfunction
- hypertrophic cardiomyopathy
- idiopathic dilated cardiomyopathy
- long QT syndrome
- Brugada syndrome
- electrolyte imbalance
- drug toxicity
- Chagas disease and other cardiomyopathies
- sleep-disordered breathing
- catecholaminergic polymorphic VT
- family history of sudden death
- mental or physical stress
Diagnostic tests
Tests to consider
- 24-hour ambulatory ECG monitoring
- echocardiogram
- cardiac catheterization
- cardiac MRI with gadolinium
- electrophysiologic testing
- stress testing
- genetic screening
Treatment algorithm
ONGOING
Contributors
Authors
Fred Kusumoto, MD

Professor of Medicine
Mayo Medical School
Division of Cardiovascular Diseases
Department of Medicine
Mayo Clinic Florida
Jacksonville
FL
Disclosures
FK declares that he has no competing interests.
Acknowledgements
Professor Kusumoto would like to gratefully acknowledge Dr Ronald R. Butendieck Jr, a previous contributor to this topic.
Disclosures
RRB declares that he has no competing interests.
Peer reviewers
Timothy Markman, MD
Assistant Professor of Medicine
Hospital of the University of Pennsylvania
Philadelphia
PA
Disclosures
TM declares that he has no competing interests.
Vias Markides, MB(Hons), BS(Hons), MD, FRCP
Consultant Cardiologist and Chair
Arrhythmias
Royal Brompton & Harefield NHS Trust
Hon. Senior Lecturer
Imperial College
London
UK
Disclosures
VM declares that he has no competing interests.
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