1. P R E S E N T E D B Y : D R . M A H E S H Y A D A V ( P . G . )
R E F E R E N E C E ( N E L S O N 2 1 T H S O U T H I N D I A A S I A E D I T I O N
A N D I N D E R B I R S I N G H T E X T B O O K O F E M B R Y O L O G Y )
DEVELOPMENT OF HEART
AND FETAL CIRCULATION
2. INTRODUCTION
CHANGES IN SINU-ATRIAL ORIFICE
FORMATION OF ATRIA
FORMATION OF INTER ATRIAL SEPTUM
DEVELOPMENT OF RIGHT ATRIUM AND LEFT ATRIUM
DEVELOPMET OF VENTRICLES
DEVELOPMENT OF INTER VENTRICULAR SEPTUM
FETAL CIRCULATION
CHANGES AFTER BIRTH IN CIRCULATION
3. INTRODUCTION
It is splanchnopleuric mesodermal in origin , from the cardiogenic
area(19days) .
First seen in the from of two Endothelial heart tubes – Right and left .
These endothelial tubes fuse together to form a single tube which shows
series of dilation
1. Bulbus cordis
2. Ventricle
3. Atrium
4. Sinus venosus
11. DEVELOPMENT OF LEFT ATRIUM
1. Left half of the primitive atrial chamber .
2. Left half of the atrio- ventricular canal .
3. Absorbed proximal parts of the pulmonary veins .
15. CONGENITAL ANAMOLY OF THE HEART
1. ACYANOTIC CONEGENITAL HEART DISEASE(LEFT TO
RIGHT SHUNT
o PATENT DUCTUS ARTERIOSUS
o ATRIAL SEPTAL DEFECT
o VENTRICULAR SEPTAL DEFECT
o COARTICATION OF AORTA
16. 2. CYANOTIC CONGENITAL HEART DISEASE
o TETRALOGY OF FALLOT
o TRANSPOSITION OF GREAT ARTERIES
o TRUNCUS ARTERIOSUS
o TRICUSPID ATRESIA
17. FETAL CIRCULATION
DEFINITION: The fetal circulation is the circulatory system of a
human fetus, often encompassing the entire fetoplacental circulation
which includes the umbilical cord and the blood vessels within
the placenta that carry fetal blood.
20. PATHWAY
Oxygenated blood from the placenta
through umbilical vein
fetus
liver
Receives deoxygenated blood from the portal vein
through ductus venosus
Inferior vena cava
Right atrium of heart
through foramen ovale
Left atrium of the heart
Left ventricle of the heart
21. During ventricular systole
Left ventricular blood Right ventricular blood
pumped with < o2 content
Ascending aorta and distributed is discharged
by their branches to the heart, Pulmonary arteries
head,neck,brain,arms. Ductus
arteriosus
Descending aorta
Hypogastric arteries
Umbilical arteries
Placenta
22. During fetal life
350ml per kg per min
Cardiac Output
Following birth
500ml per min
Heart Rate 120-140per min
23. At birth
Clamping the cord shuts down low-pressure system
Increased atmospheric pressure(increased systemic vascular
resistance) causes lungs to inflate with oxygen
Lungs now become a low-pressure system
24. CHANGES IN THE FETAL CIRCULATION AFTER BIRTH
Shunt Functional closure Anatomical
closure
Remnant
Ductus
arteriosus
10 – 96 hrs after birth 2 – 3 wks after
birth
Ligamentum
arteriosum
Formamen
ovale
Within several mins
after birth
One year after
birth
Fossa ovalis
Ductus
venosus
Within several mins
after birth
3 – 7 days after
birth
Ligamentum
venosum