Arrhythmogenic right ventricular cardiomyopathy Is it right?

Sammanfattning: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited heart disease, where sudden cardiac death in young seemingly healthy persons may be the first symptom. There is a need for more sensitive and accurate diagnostic methods to detect signs of disease, at an early stage and in relatives of affected individuals. The aim of this thesis is the evaluation of new non-invasive modalities in assessment of right ventricular (RV) volume and function with focus on patients with ARVC.Clinical and non-invasive follow-up of fifteen patients with ARVC during a mean period of 8 years permitted the evaluation of disease progression. RV volume analysis by magnetic resonance imaging relies on short axis (SA) views. A new axially rotated modality acquisition was tested and its feasibility in assessment of RV volume was evaluated. This acquisition seems to be able to improve the assessment of RV volume and function by reducing the uncertainty in defining the basal slice of the RV. A third study concentrated on analysis of RV regional and general function by echocardiography, using tissue Doppler imaging as well as two dimensional (2D) longitudinal strain based on speckle tracking in patients with ARVC, their first degree relatives and in healthy subjects. 2D strain showed a good feasibility in analysis of the RV function in relatives and controls but less in ARVC patients probably due to the progressive myocardial cell death with fibro-fatty replacement of the RV wall. In order to detect and follow up echocardiographic changes an index was developed combining dimensional and functional parameters for the left and for the right ventricle. Advances in the molecular genetics of ARVC have provided new insights into the understanding of the disease. Hitherto, 9 candidate genes have been identified. A new mutation in the plakophilin 2 gene was detected in a three generation family. The clinical phenotype related to this mutation was investigated.The studies have evaluated and developed methods for studying the right ventricle with special emphasis on ARVC. With the ultimate goal of preventing sudden death in ARVC, a combination of genetic testing and improved diagnostic methods may create an improved algorithm for risk stratification and selection to prophylactic treatment.