Arrhythmogenic right ventricular cardiomyopathy/ dysplasia (ARVC/D) was defined as a clinical entity in 1978 and in 1988 was recognised as significant among the less frequent causes of sudden death among young persons. Understanding of its complex pathogenesis and clinical manifestations has advanced during the past decade, but many aspects still await elucidation. Patients with ARVC/D either die suddenly and unexpectedly or present with arrhythmia with or without right ventricular failure. As a cause of sudden death among young people the condition could be as frequent as pulmonary embolism, myocarditis and aortic dissection together. Clinical diagnosis should be contemplated in all patients with palpitations or syncope, especially if they are young, if they ave male and if their ventricular tachycardia is of left bundle-branch morphology and exercise-induced. Electrocardiography, assessment of right and left ventricular function, and right ventricular tissue characterisation are essential for a definitive diagnosis. Late depolarisation abnormalities may be documented as an epsilon wave in leads V1 or V2 or as late potentials of signal averaged EGG. Repolarisation is also abnormal, causing an inversion of T waves in right precordial leads. Non-sustained or sustained ventricular tachycardias or frequent ventricular ectopic beats (> 1000/24 hours) usually have left bundle-branch morphology and more than one morphology might be observed. The right ventricle may be dilated globally with decreased systolic function, or segmental hypokinesia and/or dyskinesia may be documented. Left ventricular function is usually normal or slightly compromised, but can be significantly impaired at the late stage of the disease. A myocardial biopsy showing a fibrofatty infiltration of the right ventricular wall or septum confirms the diagnosis; alternatively, magnetic resonance imaging scan can be useful for tissue characterisation. The cause of ARVC/D is not well understood. The familial form is associated with the long arm of chromosome 14, and it seems prudent to screen all families in which a sudden unexpected death has occurred, especially when related to exertion. The sporadic form may be related to previous myocarditis, but this association has not been definitively proven. Involvement of the, left ventricle has been recognised and accepted as a feature of ARVC/D, especially in the advanced stages, indicating that the disease is probably another form of generalised cardiomyopathy with a preference for the right ventricle. Arrhythmogenic right ventricular cardiomyopathy/ dysplasia is a progressive disease associated with significant morbidity; however, mortality is probably less than 2% per year. Treatment options range from pharmacological intervention, catheter ablation or implantation of cardioverter/defibrillator to surgery - either right ventricular isolation or heart transplantation. All these have been used, but there are no definitive data on their efficacy and indications, so the management of the individual patient remains largely empirical.
