Development of the heart Dr. Altdorfer Development of the heart

Overview Cardiogenic plate Heart tube Devel. of the atria Devel. of the ventricles Aorticopulmonary septum Malformations

1. Cardiogenic plate 3. week Cardiogenic plate (in front of the buccopharyngeal membrane), splanchnopleura Anterior folding (4. week):

1. Cardiogenic plate Lateral folding: fusion of the endocardial heart tubes

2. Heart tube Arterial and venous ends

2. Heart tube Arterial and venous ends Bulbo-ventricular loop Transverse sinus of pericardium

3. Atria – interatrial septum

3. Atria 2 sources of the 2 sources of the right atrium left atrium

3. Atria – interatrial septum Septum spurium (sinu-atrial junction)

3. Atria – interatrial septum Septum spurium Eustach Thebesius

4. Ventricles – interventricular septum

5. Aorticopulmonary septum Divides the bulbus cordis and truncus arteriosus → aorta + pulmonary trunk Neural crest cells! Endocardial swellings, cushions Truncal ridges, bulbar ridges → spiral course

5. Aorticopulmonary septum + semilunar valves

6. Malformations Situs inversus totalis < 1:10000 Dextrocardy

6. Malformations Atrial septal defects (ASD) - ostium secundum type - persisting foramen ovale (PFO) Ventricularis septal defects (VSD) – usually at the pars membranacea region

6. Malformations

„Some people say, that the heart is a paired organ” Images: Dr. Ádám Dr. Lendvai Dr. Kozsurek