[Cardiac MR imaging in arrhythmogenic heart diseases].

INTRODUCTION Cardiac arrhythmias are assessed with a combination of history, clinical examination, electrocardiogram, Holter monitor, if necessary supplemented by invasive cardiac electrophysiology. In ischemic heart disease (IHD) coronary angiography is performed in addition. METHODS Echocardiography is usually the primary imaging modality. MRI is increasingly recognized as an important investigation allowing more accurate cardiac morphological and functional assessment. RESULTS Approximately one-fifth of deaths in Western countries are due to sudden cardiac death, 80% of which are caused by arrhythmias. Typical causes range from diseases with high prevalence (IHD in men 30%) to myocarditis (prevalence 1-9%) and rare cardiomyopathies (prevalence HCM 0.2%, ARVC 0.02%, Brugada syndrome approx. 0.5%). The characteristic MRI features of arrhythmogenic diseases and the new aspects of characteristic distribution of late enhancement allow etiologic classification and differential diagnosis. CONCLUSION MRI represents an important tool for detection of the underlying cause and for risk stratification in many diseases associated with arrhythmias.