This article summarises the potential role of invasive electrophysiological studies (EPS) for the risk stratification and management of inherited channelopathies and cardiomyopathies based on the latest clinical evidence as well as published clinical guidelines, including the American College of Cardiology/American Heart Association guidelines and the Heart Rhythm UK 2010 position statement. Generally speaking, there is no role for EPS and genetic studies in the diagnosis and risk stratification of hereditary channelopathies. Nevertheless, the controversy over the role of EPS in asymptomatic Brugada syndrome remains. In the case of inherited cardiomyopathies, there is no role for invasive EPS in symptomatic patients with hypertrophic cardiomyopathy (HCM) and atherosclerotic renovascular disease (ARVD). On the other hand, in patients with suspected HCM or AVRD, a negative EPS might be helpful in identifying the population at low risk of sudden cardiac death.
Inherited channelopathies and cardiomyopathies include diseases with a wide range of clinical manifestations, from asymptomatic gene carrier status to life-threatening cardiac arrhythmias and sudden cardiac death (SCD). Unfortunately, there is no definitive curative therapy for these diseases, which commonly affect young people. Currently, implantable cardioverter-defibrillators (ICDs) are the only option to prevent SCD in those at risk. However, ICDs impose a tremendous physical, psychological and financial burden on patients and families. It is of paramount importance to select high-risk patients who will benefit most from an ICD and to avoid overtreating low-risk groups, in whom the complications of the device outweigh the benefits. Despite advances in diagnosis and the increasingly widespread recognition of inherited channelopathies and cardiomyopathies, the risk stratification of SCD in these diseases remains challenging. The potential role of invasive electrophysiological studies (EPS) for the risk stratification and management of inherited channelopathies and cardiomyopathies based on the latest clinical evidence and published clinical guidelines is summarised in this article.1-3
Currently, four types of well-described inherited channelopathy have been linked to SCD: long QT syndrome (LQTS), short QT syndrome (SQTS), catecholaminergic polymorphic ventricular tachycardia (CPVT) and Brugada syndrome.
Long QT Syndrome
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