This thesis is separated in two parts (Part I and Part II) in which normal and abnormal heart development are studied and related to congenital heart disease, in particular to the etiology of supraventricular arrhythmias in fetuses and neonates. Part I describes the development of the posterior heart field derived venous pole of the heart specifically in correlation to the role of Shox2 and podoplanin in that particular area. Furthermore, the developmental processes in this region seem to have an important role in the anlage of the cardiac conduction system and epicardial lineage development of the heart. In the second part of this thesis (Part II) the aetiology of a specific subtype of supraventricular tachycardias i.e. atrioventricular reentry tachycardias (AVRTs) are related to normal heart development in human and mouse. AVRTs are one of the most common types of tachyarrhythmias at the perinatal period of development. We demonstrate that perinatal AVRTs might be related to incomplete formation of the isolating annulus fibrosus resulting in the temporary persistence of accessory myocardial connections between the atria and ventricles. We furthermore, demonstrate the late outcome of fetal brady- and tachyarrhythmia cases.UBL - phd migration 201
