Cardiac development : the posterior heart field and atrioventricular reentry tachycardia

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

Ductal flow ratio as a measure of transition in preterm infants after birth: a pilot study

Background: Cardiovascular changes during the transition from intra- to extrauterine life, alters the pressure gradient across the ductus arteriosus (DA). DA flow ratio (R-L/L-R) has been suggested to reflect the infant's transitional status and could potentially predict neonatal outcomes after preterm birth.Aim: Determine whether DA flow ratio correlates with oxygenation parameters in preterm infants at 1 h after birth.Methods: Echocardiography was performed in preterm infants born < 32 weeks gestational age (GA), as part of an ancillary study. DA flow was measured at 1 h after birth. DA flow ratio was correlated with FiO(2), SpO(2), and SpO(2)/FiO(2) (SF) ratio. The DA flow ratio of infants receiving physiological-based cord clamping (PBCC) or time-based cord clamping (TBCC) were compared.Results: Measurements from 16 infants were analysed (median [IQR] GA 29 [27-30] weeks; birthweight 1,176 [951-1,409] grams). R-L DA shunting was 16 [17-27] ml/kg/min and L-R was 110 [81-124] ml/kg/min. The DA flow ratio was 0.18 [0.11-0.28], SpO(2) 94 [93-96]%, FiO(2) was 23 [21-28]% and SF ratio 4.1 [3.3-4.5]. There was a moderate correlation between DA flow ratio and SpO(2) [correlation coefficient (CC) -0.415; p = 0.110], FiO(2) (CC 0.384; p = 0.142) and SF ratio (CC -0.356; p = 0.175). There were no differences in DA flow measurements between infants where PBBC or TBCC was performed.Conclusion: In this pilot study we observed a non-significant positive correlation between DA flow ratio at 1 h after birth and oxygenation parameters in preterm infants.Developmen

Balloon atrial septostomy for transposition of the great arteries: safety and experience with the Z-5 balloon catheter

BackgroundBalloon atrial septostomy (BAS) is an emergent and essential cardiac intervention to enhance intercirculatory mixing at atrial level in deoxygenated patients diagnosed with transposition of the great arteries (TGA) and restrictive foramen ovale. The recent recall of several BAS catheters and the changes in the European legal framework for medical devices (MDR 2017/745), has led to an overall scarcity of BAS catheters and raised questions about the use, safety, and experience of the remaining NuMED Z-5 BAS catheter.AimsTo evaluate and describe the practice and safety of the Z-5 BAS catheter, and to compare it to the performance of other BAS catheters.MethodsA retrospective single-center cohort encompassing all BAS procedures performed with the Z-5 BAS catheter in TGA patients between 1999 and 2022.ResultsA total of 182 BAS procedures were performed in 179 TGA-newborns at Day 1 (IQR 0–5) days after birth, with median weight of 3.4 (IQR 1.2–5.7) kg. The need for BAS was urgent in 90% of patients. The percentage of BAS procedures performed at bedside increased over time from 9.8% (before 2010) to 67% (2017–2022). Major complication rate was 2.2%, consisting of cerebral infarction (1.6%) and hypovolemic shock (0.5%). The rate of minor complications was 9.3%, including temporary periprocedural AV-block (3.8%), femoral vein thrombosis (2.7%), transient intracardiac thrombus (0.5%), and atrial flutter (2.2%). BAS procedures performed at bedside and in the cardiac catheterization laboratory had similar complication rates.ConclusionsBAS using the Z-5 BAS catheter is both feasible and safe at bedside and at the cardiac catheterization laboratory with minimal major complications.Thoracic Surger

Perinatal management and long-term cardiac outcome in fetal arrhythmia

Item does not contain fulltextBACKGROUND: cardiac arrhythmias are commonly observed in the fetus, however, may have major consequences for fetal development and post natal life. AIMS: to evaluate the perinatal management and cardiac outcome of fetuses with tachy- or bradyarrhythmia. STUDY DESIGN: perinatal management, outcome and long-term cardiac follow-up were evaluated retrospectively in consecutive fetuses with cardiac arrhythmias. RESULTS: forty-four fetuses were diagnosed: supraventricular tachycardia (SVT, n=28), atrial flutter (AF, n=7) and atrioventricular block (AVB, n=9). The overall incidence of cardiac anomalies was 18% mainly in the AVB group; hydrops was present in 34%. Direct or transplacental fetal anti-arrhythmic medication was given in 76%. Mortality was 6% in SVT/AF and 78% in the AVB group, respectively. AF resolved in all patients. In the SVT group, Wolff-Parkinson-White (WPW) syndrome was present in 21%, diagnosed at birth or later in life. After the age of one year about 90% of patients in the SVT group remained asymptomatic and free of drugs (median follow-up 76months). CONCLUSIONS: mortality rate is low in patients with fetal SVT and AF but high in patients with AVB. Related morbidity includes WPW-syndrome and congenital cardiac anomalies. Electrocardiographic screening is recommended in all fetal SVT cases before adolescence since WPW-syndrome may occur later in life

Normal and abnormal development of the cardiac conduction system; implications for conduction and rhythm disorders in the child and adult

Cardiolog

Accessory Atrioventricular Myocardial Pathways in Mouse Heart Development: Substrate for Supraventricular Tachycardias

Cardiac Dysfunction and Arrhythmia

Echocardiographic Assessment of Embryonic and Fetal Mouse Heart Development: A Focus on Haemodynamics and Morphology

Cardiolog

Abnormal sinoatrial node development resulting from disturbed vascular endothelial growth factor signaling

Cardiolog