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Dr Anil Dwivedi
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Outline
Early development with regulating Genes.
Primordial Heart circulation.
Partitioning of AV canal.
Partitioning of Primordial Atrium.
Changes in Sinus Venosus.
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Formation of RA & LA.
Partitioning of Primordial Ventricle & BC.
Development of Cardiac Valves & Conducting System.
Congenital Anomalies.
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DEVELOPMENT OF HEART
•CVS – 1st major system.•why?•From-
•splanchnic mesoderm•paraxial & lat meso •neural crest cells.
•Earliest sign – angioblastic cords.
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•18 days embryo.•Dorsal view
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•Angioblastic cord in cardiogenic area.•Pericardial coelom.
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•4th week•Effect of head fold on position of Heart•Septum transversum-central tendon of Diaph.
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•20 days•Dorsal view•Two endocardial Heart tube & lat fold.
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•22 days•Formation of pericardial cavity & fusing heart tubes•Single Heart tube suspended by dorsal mesocardium
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•28 days•Degeneration of central part of dorsal mesocardium•Formation of Tr. Sinus•Three layers of Heart wall.
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Genetic basis of growth of heart tube
6 HLH
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•Rt & Lt Heart tubes•Cranial to caudal fusion•Partial fusion of Sinus Venosus.
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Subdivisions of Heart tube & their fate
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26 dayshorns of sinus Venosus
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• The Bulbus cordis moves Inf Ant & to the embryo Rt.
• The primitive ventricle moves to Lf
• The prim Atrium & Sinus venosus moves sup & post
• Sinus venosus is post to atrium.
Early Heart development & folding of primitive Heart tube
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Early Heart development & folding of primitive Heart tube
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Circulation through primordial Heart
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Partitioning of Atrioventricular canal
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Partitioning of Atrioventricular canal
Partition of the Atrioventricular canal
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Partitioning of primordial Atrium
•4th week•Septum primum•Foramen primum•Foramen secundum•Septum secundum•Foramen ovale
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Partitioning of primordial Atrium
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Partitioning of primordial Atrium
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Partitioning of primordial Atrium
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Partitioning of the primordial atrium
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Changes in the Sinus Venosus
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Changes in the Sinus Venosus
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Changes in the Sinuatrial Orifice
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Formation of the Right AtriumRt ½ primitive atriumSinus venosusRt ½ AV canal
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Formation of the Right Atrium
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Formation of the Left Atrium & PPV
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Partitioning of primordial Ventricle
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Partitioning of primordial Ventricle
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Partitioning of primordial Ventricle
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Partitioning of Bulbus Cordis & TA
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Developments of the Cardiac Valves
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Developments of the Cardiac Valves
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Developments of the Cardiac Valves
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Conducting system of the Heart
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Anomalies of the Heart
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Anomalies of the Heart
• Dextrocardia
Anomalies of Position
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Anomalies of the HeartAnomalies of PositionEctopia Cardis
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Atresia or Stenosis
• Aortic valve Stenosis• Pulmonary valve Stenosis
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Defective formation of septa
ASD• Patent oval foramen.• F>M• Probe patent foramen
incomplete adh of sep sec.
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Defective formation of septaASD• Ostium secundum ASD
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Defective formation of septaASD• Endocardial cushion defect with Ostium primum ASD
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Defective formation of septaASD
• Sinus Venosus ASD
• Common Atrium.
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Defective formation of septaVSD- most common CHD. -25%, M>F, • Membranous – most common.
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Defective formation of septaVSD• Muscular(Swiss cheese)• Single ventricle
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Persistent Truncus ArteriosusFailure of-• Truncal ridges• aorticopulmonaryseptum
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Transposition of Great Arteries
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Tetralogy of Fallot• Pulmonary Stenosis• VSD• Overriding of aorta• Right ventricular
hypertrophy
Unequal div of TA
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SUMMARY
1. Formation and division of the heart tube;
2. Partitioning of Atrioventricular canal, atrium, ventricle, and Truncus and Bulbus;
3. Congenital heart diseases.