AKA Arrhythmogenic Right Ventricular Dysplasia (ARVD)
Arrhythmogenic Right Ventricular Cardiomyopathy Overview
- An inherited myocardial disease associated with paroxysmal ventricular arrhythmias and sudden cardiac death.
- Characterized pathologically by fibro-fatty replacement of the right ventricular myocardium.
- The second most common cause of sudden cardiac death in young people (after HOCM), causing up to 20% of sudden cardiac deaths in patients < 35 yrs of age.
- Typically inherited as an autosomal dominant trait, with variable penetrance and expression (there is an autosomal recessive form called Naxos Disease, which is associated with woolly hair and skin changes).
- More common in men than women (3:1) and in people of Italian or Greek descent.
- Estimated to affect approximately 1 in 5,000 people overall.
Diagnosis of ARVC
There is no single diagnostic test for ARVC. The diagnosis is made using a combination of clinical, electrocardiographic and radiological features, as defined by the (horribly complicated) 2010 Task Force Criteria.
- ARVC causes symptoms due to ventricular ectopic beats or sustained ventricular tachycardia (with LBBB morphology) and typically presents with palpitations, syncope or cardiac arrest precipitated by exercise.
- The first presenting symptom may be sudden cardiac death.
- Over time, surviving patients also develop features of right ventricular failure, which may progress to severe biventricular failure and dilated cardiomyopathy.
- There is usually a family history of sudden cardiac death.
ARVD is associated with characteristic ECG abnormalities:
- Epsilon wave (most specific finding, seen in 30% of patients)
- T wave inversions in V1-3 (85% of patients)
- Prolonged S-wave upstroke of 55ms in V1-3 (95% of patients)
- Localised QRS widening of 110ms in V1-3
- Paroxysmal episodes of ventricular tachycardia with LBBB morphology (e.g. right ventricular VT).
- See more examples of Epsilon waves
Prolonged S-wave upstroke and localized QRS widening in V2
- Note: Some authors recommend recording ECG rhythm strips at double speed and double amplitude to enhance the detection of some of these features
- Read more about Right ventricular VT.
- Echocardiography is the first-line investigation, and may demonstrate a dilated, hypokinetic right ventricle with prominent apical trabeculae and dilatation of the RV outflow tract.
- The imaging modality of choice in many centres is cardiovascular MRI, which can accurately demonstrate structural and functional features of ARVD such as fibrofatty infiltration and thinning of the RV myocardium, RV aneurysms, RV dilatation, regional wall motion abnormalities and global systolic dysfunction.
- Other imaging modalities such as CT scanning and right ventricular contrast angiography may be used to make the diagnosis where MRI is unavailable, but have the disadvantages of high radiation burden and/or invasive technique.
- Histological diagnosis, either via endomyocardial biopsy or at autopsy, provides a definitive diagnosis but is impractical, and for those patients diagnosed at post-mortem… far too late!
Patients with ARVD are considered to be at high risk of sudden death if they have any of the following:
- A history of syncope due to cardiac arrest
- Recurrent arrhythmias not suppressed by anti-arrhythmic drug therapy
- A family history of cardiac arrest in first degree relatives
- In patients with no high risk features, initial treatment is with anti-arrhythmic drugs such as beta-blockers or amiodarone to suppress cathecholamine-triggered ventricular arrhythmias. Currently, the most effective drug for this is sotalol.
- Patients with any high risk features require urgent insertion of an implantable cardioverter-defibrillator (ICD).
- In patients with persistent symptomatic arrhythmias, radiofrequency ablation of conduction pathways may be attempted.
- Heart failure is treated in the usual way, with diuretics, ACE inhibitors and anticoagulants. In severe cases, cardiac transplantation may be required.
Learn From The Experts!
- Dr Smith’s ECG Blog — ARVC
- Anderson EL. Arrhythmogenic right ventricular dysplasia. Am Fam Physician. 2006 Apr 15;73(8):1391-8
- ARVD.com. The website of the Johns Hopkins ARVD Patient Registry based in Baltimore, Maryland.
- Perez Diez D, Brugada J. Diagnosis and Management of Arrhythmogenic Right Ventricular Dysplasia: An article from the E-Journal of the ESC Council for Cardiology Practice, European Society of Cardiology 2008
- Protonotarios N, Tsatsopoulou A. Naxos disease. Indian Pacing Electrophysiol J. 2005 Apr 1;5(2):76-80. [PMID: 16943947]
- Brady WJ, Truwit JD. Critical Decisions in Emergency and Acute Care Electrocardiography
- Hampton, JR. The ECG In Practice, 6e
- Surawicz B, Knilans T. Chou’s Electrocardiography in Clinical Practice: Adult and Pediatric, 6e
- Wagner, GS. Marriott’s Practical Electrocardiography 12e
- Chan, TC. ECG in Emergency Medicine and Acute Care
- Mattu, A. ECG’s for the Emergency Physician
LITFL Further Reading
- ECG BASICS — Waves, Intervals, Segments and Clinical Interpretation
- ECG A to Z by diagnosis –alphabetical diagnostic approach to the ECG
- ECG CLINICAL CASES — ECG’s placed in clinical context with a challenging Q&A approach
- 100 ECG Quiz — Self-assessment tool for examination practice
- ECG Reference SITES and BOOKS — the best of the rest
- LITFL ECG IMAGE Database — Searchable database of LITFL ECG’s
- ECG and Cardiology Eponymous Syndromes — Cheats guide to eponymous emancipation
- ECG Exam Template — a framework for answering ECG exam questions.