The aim of this website is to provide information and tools to better understand and manage patients with Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC). A brief section for patients and the public is provided, with links to additional sites for patients and the public. Key elements to look into are:
Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) is an inherited condition characterized by onset of life threatening ventricular arrhythmias in early adulthood, presenting with ventricular tachycardia, cardiac arrest or sudden death. The disease is diagnosed with tests that focus on imaging the right ventricle and assessing for ambient arrhythmia or abnormal electrical substrate. These factors are entered into a score that forms the ARVC Task Force Criteria, known to be specific but not sensitive. These criteria have been revised in 2010, introducing a broader and more quantitative approach to diagnosis including genetic testing results, intended to enhance sensitivity without reducing specificity. They account for findings from genetic testing, confounded in part by the unknown significance of a positive genetic test in the absence of a phenotype in a disease with variable penetrance and expressivity. Genetic testing identifies the underlying mutation in ≈50% of clearly affected patients in one of 6 genes, the most common of which is plakophilin. Recent access to genetic testing has demonstrated that family members of an affected individual often harbor the culprit mutation, with little evidence that they are affected from clinical testing.
The precise cause of ARVC is not known, but the commonly held explanation is that ARVC is a condition that weakens the cell junction (desmosome). The majority of gene positive patients have mutations that affect the genes that code for the components of the cell junction. ARVC is familial. The pattern of inheritance is autosomal dominant, such that the child of an affected parent will have 50% chance of inheriting the abnormal gene. The disease affects men and women equally and has been recognised in people of diverse ethnic origin. It is common to be affected and not have any symptoms, and testing shows varying degrees of abnormalities. This is termed variable penetrance and expressivity.
Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) is an inherited condition characterized by life threatening heart racing, presenting with palpitations, cardiac arrest (collapse requiring an ambulance) or sudden death. The disease affects the right ventricle, the part of the heart that pumps blood to the lungs. ARVC is diagnosed with a wide range of tests that focus on the pumping function and the electrical signals from the right ventricle. There are a number of methods used to diagnose ARVC: ECG, echocardiogram, Holter Monitoring, signal averaged ECG, stress testing, cardiac MRI, right ventricular angiography, electroanatomic mapping and rarely tissue biopsy. These tools can detect an abnormal electrical signal from the involved muscle tissue, or structural abnormalities. The variable presentation typically leads the physician to perform broad testing, since no single test is a gold standard for the diagnosis. Test results, and personal and family history are the basis of the ARVC Task Force Criteria, which assists physicians in making a clinical diagnosis. These have recently been revised, and represent a major complex system based on a broad approach to investigation that is used to identify the strength of the diagnosis.The variable presentation typically leads the physician to perform broad testing, since no single test is a gold standard for the diagnosis.
Genetic testing has identified 6 different genes that lead to ARVC, which are detected in about 60% of patients with ARVC. This allows doctors to test family members of the patient with ARVC to determine if they are at risk of developing the condition. Currently, patients with known or suspected ARVC and their family members undergo testing that includes imaging and electrical tests such as a 24-hour monitor to determine if they have evidence of ARVC. With increasing frequency, family members are found to have the gene that may lead to ARVC, but little or no evidence that their hearts are affected. This may be because the family member is too young to develop the condition, or that other factors that we do not understand have protected them from developing it. Active research is ongoing to better understand this condition.