What is Arrhythmogenic Right Ventricular Dysplasia?

A heart is a four-chambered, blood-pumping organ made up of muscles. In arrhythmogenic right ventricular dysplasia (AVRD), the right ventricle of the heart is primarily affected wherein its muscular portion is progressively replaced by fibrofatty tissues. The left ventricle may also be affected, but to a much lesser extent. Arrhythmogenic right ventricular dysplasia/cardiomyopathy (AVRD/C) is a heart disease inherited in an autosomal dominant manner that predisposes the affected individual to excessive rapid heart rate, fainting due to sudden loss of consciousness, and death. During clinical examination, an affected individual may present with nonspecific heart disorder-related signs such as jugular vein distension, enlarged liver, and edema.

The diagnosis of arrhythmogenic right ventricular dysplasia is established by fulfilling two major criteria, or one major and two minor criteria, or four minor criteria, which can be obtained through a thorough history taking and a combination of noninvasive and invasive diagnostic tests. Noninvasive testing includes electrocardiogram, cardiac computed tomography scan, cardiac magnetic resonance imaging, echocardiography, and Holter monitoring. Invasive testing includes right ventricular angiography, electrophysiological testing, and right ventricular endomyocardial biopsy. Major criteria include severe global or segmental dilation of the right ventricle, localized aneurysms in the right ventricle, fibrofatty replacement of heart muscles, QRS prolongation localized to the right precordial leads, and presence of the disease, confirmed at surgery or necropsy, in an immediate family member. Minor criteria include mild global or segmental dilation of the right ventricle, inverted T waves localized to the right precordial leads, left bundle branch block ventricular tachycardia, and family history of sudden death at less than 35 years of age in an immediate family member.

Management of persons with arrhythmogenic right ventricular dysplasia is individualized and focused on prevention of excessive rapid heart rate, fainting due to sudden loss of consciousness, and death. Prevention of these can be done through the use of antiarrhythmic drugs such as amiodarone and sotalol, implantable cardioverter-defibrillators, and education. Implantable cardioverter-defibrillators are considered for high-risk individuals such as those who are intolerant or unresponsive to antiarrythmic drugs, those who have been resuscitated, and those with family history of sudden cardiac arrest. Education about the risk of sudden death should involve not only the affected individuals but also their family members.

Regular screening of the affected individuals and molecular genetic testing of immediate family members at risk are also important. Screening is done annually, or more often depending on the symptoms, through the use of electrocardiogram, echocardiogram, or cardiac magnetic resonance imaging. Genetic testing reduces complications and death by early diagnosis and treatment.