Arrythmogenic Right Ventricular Dysplasia / Cardiomyopathy (ARVD/ARVC)

Introduction

genetic disease of desmosome dysfunction resulting in the progressive replacement of the RV myocardium by fatty fibrous tissue which slows cardiac impulse conduction through the RV
may account for 3-5% of sudden cardiac death under the age of 65 years as it may cause exercise or catecholamine-induced LBBB pattern Right Ventricular Outflow Tract Tachycardia (RVOT) and ventricular fibrillation (VF), while survivors often develop RV failure

Epsilon wave - a small positive deflection at the very end of the QRS complex
- Fontaine bipolar precordial leads (F-ECG) are used to increase the sensitivity of epsilon wave detection
T wave inversion in V1-3
localized QRS widening and prolonged S-wave upstroke in V1-V3
see https://litfl.com/arrhythmogenic-right-ventricular-dysplasia-arvd/

a cyclic-AMP-mediated form of VT that is classically triggered by exercise or catecholamine excess
ventricular tachycardia (VT) with a LBBB pattern
- this needs to be differentiated from:
  - supraventricular tachycardias (SVT) with LBBB
  - supraventricular tachycardias (SVT) with WPW
  - see https://lifeinthefastlane.com/ecg-library/basics/vt_vs_svt/
2 main causes of RVOT:
- Idiopathic RVOT these patients have structurally normal hearts, more common in women, generally benign
- ARVD

patients with high risk features require urgent insertion of an implantable cardioverter-defibrillator (ICD)
anticoagulation to prevent RV thrombus formation
beta adrenergic blockers such as sotalol to reduce catecholamine-triggered VT/VF if no ICD inserted