Fetal ECHO Meeting 2012

From Embryology
Embryology - 28 May 2024    Facebook link Pinterest link Twitter link  Expand to Translate  
Google Translate - select your language from the list shown below (this will open a new external page)

العربية | català | 中文 | 中國傳統的 | français | Deutsche | עִברִית | हिंदी | bahasa Indonesia | italiano | 日本語 | 한국어 | မြန်မာ | Pilipino | Polskie | português | ਪੰਜਾਬੀ ਦੇ | Română | русский | Español | Swahili | Svensk | ไทย | Türkçe | اردو | ייִדיש | Tiếng Việt    These external translations are automated and may not be accurate. (More? About Translations)


Dr Mark Hill


This presentation will introduce development of the heart from its earliest origins through to the end of the embryonic period. The main morphological changes in the human heart will be shown in the context of the normal human timeline of development.

Ultrasound scans that occur at the end of the first trimester should show a heart that has completed all aspects of septation (atrial, ventricular and outflow tract).

Heart differences from the adult circulation will be present within the heart the atrial shunt (foramen ovale, or historically foramen Botalli) and just outside the heart the pulmonary-aortic arch shunt (ductus arteriosus).

Note - Please take the opportunity now in your own time to look at the various animations on this page that help your understanding of cardiac development. This page also contains "collapsed tables" that can be opened to show more detailed information.

Please feel free to provide the author Feedback, as I continue to improve the content even after the conference!

Developmental Timings

  • Clinical timings refer to Gestational Age (GA) from the last day of the Last Menstrual Period (LMP).
  • Embryonic timings refer to Ovulation age (OA) from day 14 of the cycle when fertilization occurs.

Other Cardiovascular Pages

Teach yourself about heart development with these online tutorials designed at different 3 levels.

Cardiac Embryology     Begin Basic     Begin Intermediate     Begin Advanced  

The pages below are more detailed descriptions of cardiovascular development, most outside the scope of this presentation. Probably the most relevant page is Abnormalities.

Cardiovascular Links: cardiovascular | Heart Tutorial | Lecture - Early Vascular | Lecture - Heart | Movies | 2016 Cardiac Review | heart | coronary circulation | heart valve | heart rate | Circulation | blood | blood vessel | blood vessel histology | heart histology | Lymphatic | ductus venosus | spleen | Stage 22 | cardiovascular abnormalities | OMIM | 2012 ECHO Meeting | Category:Cardiovascular
Historic Embryology - Cardiovascular 
1902 Vena cava inferior | 1905 Brain Blood Vessels | 1909 Cervical Veins | 1909 Dorsal aorta and umbilical veins | 1912 Heart | 1912 Human Heart | 1914 Earliest Blood-Vessels | 1915 Congenital Cardiac Disease | 1915 Dura Venous Sinuses | 1916 Blood cell origin | 1916 Pars Membranacea Septi | 1919 Lower Limb Arteries | 1921 Human Brain Vascular | 1921 Spleen | 1922 Aortic-Arch System | 1922 Pig Forelimb Arteries | 1922 Chicken Pulmonary | 1923 Head Subcutaneous Plexus | 1923 Ductus Venosus | 1925 Venous Development | 1927 Stage 11 Heart | 1928 Heart Blood Flow | 1935 Aorta | 1935 Venous valves | 1938 Pars Membranacea Septi | 1938 Foramen Ovale | 1939 Atrio-Ventricular Valves | 1940 Vena cava inferior | 1940 Early Hematopoiesis | 1941 Blood Formation | 1942 Truncus and Conus Partitioning | Ziegler Heart Models | 1951 Heart Movie | 1954 Week 9 Heart | 1957 Cranial venous system | 1959 Brain Arterial Anastomoses | Historic Embryology Papers | 2012 ECHO Meeting | 2016 Cardiac Review | Historic Disclaimer

Human Embryo Development

Human development timeline graph 01.jpg

Weeks shown are ovulation age (OA) for gestational age (GA) add 2 weeks.

Carnegie Stages: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | About Stages | Timeline

Human Carnegie stage 1-23.jpg

The above images of human embryonic development to week 8 (gestational age week 10) show the changing growth in size (all to scale) and external appearance of the embryo. Note that by the end of this period, covering most of the first trimester, the embryo is only about 3 cm long.

Heart Embryonic Timeline

Advanced Heart Development Timeline GA.jpg

Weeks shown above are for clinical Gestational Age (GA). Ages shown below are Ovulation Age (OA), subtract 2 weeks from GA. If the linked Advanced pages below are too difficult, try starting with the Basic or Intermediate level descriptions of the same events.

Begin Advanced Heart Fields Heart Tubes Cardiac Looping Cardiac Septation Outflow Tract Valve Development Cardiac Conduction Cardiac Abnormalities Molecular Development

Cardiovascular Movies

These simple cartoons show, almost in developmental sequence, aspects of cardiac development. Each linked page is supported by simple descriptions of events shown in the movie.

Week3 folding icon.jpg
 ‎‎Week 3
Page | Play
Whole Embryo Folding

The animation shows how the folding of the whole embryo in week 3-4 (GA week 5-6) brings the cardiac region into its anatomical location.

Heart1 looping icon.jpg
 ‎‎Heart Looping
Page | Play
Heart Looping

The early heart tube buckles and folds as it grows in length, forming the initial shape of the future heart.

Heart1 realign icon.jpg
 ‎‎Heart Realign
Page | Play
Ventricular Growth

As the ventricular region grows there is a realignment of the ventricles in the developing heart tube.

Heart1 atrium icon.jpg
 ‎‎Atrial Septation
Page | Play
Atrial Septation

The division of the atria occurs by the growth of two separate overlapping septa in the embryonic period. Note that both septa are not complete and allow blood to pass between the two atria during the entire prenatal period (embryonic and fetal).

Heart1 ventricle icon.jpg
 ‎‎Outflow Septation
Page | Play
Outflow Septation

The ventricles initially separate by growth of the inferior muscular wall. Later the superior region separates by outgrowth of membranous regions that extend into the outflow tract. This third and final septation, leads to a separation of the pulmonary and aortic arch circulations. (Note that a shunt, the ductus arteriosus will persist through the entire prenatal period (embryonic and fetal).

Heart1 atrium.gif
Additional Movies
Heart fields 001 icon.jpg
 ‎‎Heart Fields
Page | Play
Heart folding 002 icon.jpg
 ‎‎Primitive Heart Tube
Page | Play
Heart folding 001 icon.jpg
 ‎‎Heart Tubes
Page | Play
Heart looping 006 icon.jpg
 ‎‎Cardiac Looping
Page | Play
Heart septation 001 icon.jpg
 ‎‎Cardiac Septation
Page | Play
Outflow tract 001 icon.jpg
 ‎‎Outflow Tract
Page | Play
The historic movies below include an audio commentary of cardiac development events (note the audio is unfortunately quite poor).
Historic Heart Development Movies (Historic Disclaimer)
Heart historic 001 icon.jpg
Page | Play
Heart historic 002 icon.jpg
 ‎‎Week 3
Page | Play
Heart historic 003 icon.jpg
 ‎‎Week 3-5
Page | Play
Heart historic 004 icon.jpg
 ‎‎Week 4-11
Page | Play
Heart historic 005 icon.jpg
 ‎‎Embryo overview
Page | Play
Heart historic 006 icon.jpg
 ‎‎AV Septation
Page | Play
Heart historic 007 icon.jpg
 ‎‎Outflow Septation
Page | Play
Heart historic 008 icon.jpg
Page | Play

Heart Field

Mesoderm 001 icon.jpg
 ‎‎Week 3 Mesoderm
Page | Play

Week 5 (GA)


Carnegie stage 7

Early Heart Tube (Dorsal).jpg

Dorsal view of 18 day embryo

Early Heart Tube (Lateral).jpg

Lateral view of 18 day embryo

Heart fields 001 icon.jpg
 ‎‎Heart Fields
Page | Play
Week3 folding icon.jpg
 ‎‎Week 3
Page | Play
  • The heart primordium arises predominantly from the primary heart field in splanchnic mesoderm forming in the cardiogenic region of the trilaminar embryo.
  • The cardiogenic region can be thought of as bilateral fields that merge cranially to form a horseshoe-shaped field.
  • During the third week (PO) of development (approximately day 18) angioblastic cords develop in this cardiogenic mesoderm and canalise to form bilateral endocardial heart tubes.
  • The secondary heart field has been described as pharyngeal mesenchyme that contributes myocardium and smooth muscle to the arterial pole.

Heart Tube

Heart Tube Fusion.jpg

Week 5 (GA) to beginning Week 6 (GA)

Heart Tube Segments.jpg

  • The endothelium of the heart tube forms the internal endocardium.
  • The epicardium develops from mesothelial cells arising from the sinus venosus, that spread cranially over the myocardium.

Cardiac Looping

Human heart SEM1.jpg

Image day 21 to 25 (GA Week 6)

Heart Looping Sequence (SEMs).jpg

Stage10 bf3.jpg
  • First stage occurs from late in the sixth week (GA) to early in the seventh week (GA)
    • studied in chick embryos whose initial, straight heart tube is representative of that developing in humans.
  • Second stage (creating S-shape) occurs as the ventricular bend moves caudally and the distance between the outflow and inflow tracts diminishes.
    • dorsal mesocardium degenerates forming the transverse pericardial sinus (a point of communication across the pericardial coelom).
    • atrial and outflow poles converge and myocardial cells are added, forming the truncus arteriosus.
  • Final stage is the wedging of the aorta between the atrioventricular (AV) valves.
    • occurs during septation and is dependent on the retraction and rotation of the myocardium by 45°.

Left-Right Asymmetry

  • Heart is the first organ in the body to express left-right asymmetry in the form of looping.
  • The axis of the heart is established earlier during gastrulation (week 3, GA week 5).

In the first images below the cardiac sac (pericardial sac) has been opened to show the developing heart tube.

Stage11 sem8a.jpg

Stage11 sem5c.jpg

Stage12 sem1.jpg Stage13 bf6.jpg

Stage13 sem1c.jpg

Stage 11 Stage 12

Stage 12 detail

Stage 13

atrioventricular junction


Atrioventricular Canal

  • Partitioning of the primitive heart occurs between the middle of the week 6 (GA) and the end of week 7 (GA).
  • Division of the atrioventricular canal is described below while

Two endocardial cushions form on the dorsal and ventral surfaces of the AV canal. Following expansion of the cardiac jelly, epithelial to mesenchymal transformation (EMT) of the endocardial cells in the canal occurs forming the cushions. Synergistic signalling between BMP and TGFβ facilitates EMT. The cushions grow as they are invaded by mesenchymal cells from the endocardium during the fifth week, eventually fusing to create the right and left AV canals, hence partially separating the primitive atrium and ventricle.

Links: Atrioventricular Canal Septation

Atrial and Ventricular Septation

Development of the Atria
Heart1 atrium icon.jpg
 ‎‎Atrial Septation
Page | Play
Membranous tissue forming the septum primum grows from the roof of the atrium, dividing it into left and right halves. The septum primum originates from myocardium that differentiates from splanchnic mesoderm near the venous pole and approaches the endocardial cushions. The foramen primum refers to the decreasing communication between the septum primum and endocardial cushions. The junction of the septum primum and endocardial cushions becomes myocardialised by ingrowth of myocardial cells, although the centre is maintained as dense connective tissue and is referred to as Todaro’s tendon. Apoptosis-induced perforations appear in the centre of the septum primum to produce the foramen secundum. At this time, the strong, muscular septum secundum grows immediately to the right of the septum primum and gradually overlaps the foramen secundum during the fifth and sixth weeks of development. Part of the atrial septum and dorsal right atrium, as well as the septum secundum develop from left-sided mesenchyme. The incomplete partition of the atrium by the septum secundum forms the foramen ovale. Blood flows through the foramen ovale and foramen secundum to the left atrium. The remaining portion of the septum primum acts as the valve of the foramen ovale. Blood cannot flow in the opposite direction as the muscular strength of the septum secundum prevents prolapse of the septum primum.

Remodelling of the venous pole, including the further induction of myocardial cells, contributes to the development of the atria. In the mouse, myocardial differentiation occurs in the dorsal mesocardium and cells are then recruited to the venous pole. The development of two left to right shunts in the venous system leads to an increase in the right horn of the sinus venosus and consequentially a decrease in left horn by the end of the fourth week (GA 6 week). The sinuatrial orifice correspondingly shifts to the right thus becomes located in the right atrium. Hence the right atrium receives the superior vena cava (SVC) and inferior vena cava (IVC) in the adult. In mice and chicks the left sinus horn develops as the left SVC, however this regresses to form the coronary sinus in humans. Thus the sinus venosus gradually becomes incorporated into the right atrium. It contributes to the smooth walled part of the adult right atrium, referred to as the sinus venarum. The trabeculated right atrium corresponds to the primordial atrium; the division between these structures is indicated by the inner crista terminalis and outer sulcus terminalis. The primordial pulmonary vein develops in the dorsal wall of the left atrium. As the atrium increases in size it incorporates more of the branches of the pulmonary vein, culminating in its receiving the four pulmonary veins. The smooth wall of the adult left atrium originated from the primordial pulmonary vein, while the trabeculated wall represents the primordial atrium.

Heart1 atrium icon.jpg
 ‎‎Atrial Septation
Page | Play
Development of the Ventricles
Heart1 realign icon.jpg
 ‎‎Heart Realign
Page | Play
Minor trabeculations appear during early development of the primordial ventricle. Following growth of the ventricles further trabeculations appear and grow as larger, muscular structures. Some authors tout the idea that as trabeculations grow they coalesce resulting in the formation of the ventricular septum. However, the more commonly described theory of septation begins with the appearance of a primordial muscular interventricular (IV) ridge developing in the floor of the ventricle near the apex. As either side of the ventricle grows and dilates, their medial walls fuse forming the prominent IV septum. The foramen located between the cranial portion of the IV septum and the endocardial cushions, the IV foramen, closes by the end of the seventh week (GA 9 week) as the bulbar ridges fuse with the endocardial cushions.

Links: Atrial and Ventricular Septation

Outflow Tract Septation

  • Cardiac neural crest - levels associated with somites 1 and 3 of the neural tube migrate through the pharyngeal arches to contribute to the conotruncal septum.
  • Week 7 (GA) - proliferation of pharyngeal mesenchyme in the bulbus cordis forms bulbar ridges, continuous in the truncus arteriosus. Cardiac neural crest migrates into these ridges, condensing as cellular columns to support the outflow tract septum. The ridges form a 180° spiral to create the helical aorticopulmonary septum. Myocardialisation of the ridges gives a zippering effect resulting in fusion.
  • Week 8 (GA) - fusion occurs distal to proximal direction, allowing for cleavage of the aorta and pulmonary trunk. The spiralling nature of the ridges causes the pulmonary trunk to twist around the aorta. The bulbus cordis accounts for the smooth conus arteriosus (or infundibulum) in the right ventricle and the aortic vestibule in the left ventricle.
Migration of the cardiac neural crest
Cross-sections of the outflow tract illustrating the truncal and bulbar ridges
Links: Movie - Outflow tract

Heart Week 7 and 10 (GA)

The images below and the associated collapsed tables show detailed histological images of heart development at about the midpoint (week 5, GA week 7) and at the end (week 8, GA week 10) of human embryonic development. (Note - These are in more detail than you currently require, but clearly show the position, size and shape of the heart in the embryo).

Section through the length of the (week 5, GA week 7) embryo.
Stage 13 image 097.jpg Stage 13 image 098.jpg
Stage 13 Embryo (GA Week 7)
Stage 13 image 057.jpg Stage 13 image 058.jpg Stage 13 image 059.jpg Stage 13 image 060.jpg Stage 13 image 061.jpg Stage 13 image 062.jpg Stage 13 image 063.jpg
Stage 13 image 064.jpg Stage 13 image 065.jpg Stage 13 image 066.jpg Stage 13 image 067.jpg Stage 13 image 068.jpg Stage 13 image 069.jpg Stage 13 image 070.jpg
Stage 13 image 071.jpg Stage 13 image 072.jpg Stage 13 image 073.jpg Stage 13 image 074.jpg Stage 13 image 075.jpg Stage 13 image 076.jpg Stage 13 image 077.jpg
Stage 22 Embryo (GA Week 10)
Section Name Description
Stage 22 image 069.jpg C6L L and R common carotid arteries. L and R internal jugular veins.
Stage 22 image 070.jpg C7L L brachiocephalic vein (transverse anastomosis of L, R jugular veins). L common carotid artery. Brachiocephalic trunk.
Stage 22 image 071.jpg D1L Aortic arch. Thymus (retrosternal). Trachea. Oesophagus. Large L and R jugular veins.
Stage 22 image 072.jpg D2L Aortic arch. L jugular lymph sac lying laterally with hemiazygos joining it. Trachea. Oesophagus. Draining of azygos vein into R jugular vein.
Stage 22 image 073.jpg D3L Ascending aorta attached cranial to transverse pericardial sinus. Superior vena cava expanding into R jugular vein. Trachea (bifurcation). Oesophagus. Azygos (R) and hemiazygos (L) veins.
Stage 22 image 074.jpg D4L Ascending aorta. Pulmonary trunk and arteries. Thoracic aorta. Oesophagus. Bronchi. Note azygos vein on right, and precursor of hemiazygos vein on left side.

(Image excerpt different scale from previous images)

Stage 22 image 075.jpg D5L Superior vena cava. Ascending arch of aorta. Pulmonary trunk with the other two semilunar valves.

Sinus above one valve and branching of pulmonary trunk into L and R pulmonary arteries.

Stage 22 image 076.jpg D6L Superior vena cava. Ascending aorta with transverse pericardial sinus behind. Semilunar valve at origin of pulmonary trunk. L. atrium and auricle. Thoracic aorta.
Stage 22 image 077.jpg D7L R atrium with R venous valve. R ventricle close to origin of pulmonary trunk. L.ventricular wall and three semilunar valves of aortic ostium.
Stage 22 image 078.jpg E1L Section through all four chambers of heart.

left ventricle- outflow tract close to origin of ascending aorta. Deep coronary sulcus and transverse pericardial sinus.

right atrium- R venous valve of the inferior vena cava, the small septum secundum, the aperture in the dorsal part of septum primum (ostium secundum). (The foramen ovale arises later with the elongation of the septum secundum).

left atrium- entrance of the L and R pulmonary veins and the auricle.

Stage 22 image 079.jpg E2L Section through all four chambers of heart.

Ventricles. Right venous valve. Between the tiny ridge of the septum secundum of the R atrium and the R venous valve.

right atrium- drainage of the inferior vena cava (cf. E3). R atrioventricular canal. Septum primum.

left atrium- drainage sites of R and L pulmonary veins.

Stage 22 image 080.jpg E3L Section through all four chambers of heart.

Ventricles. Diaphragm and liver. Pericardium and cavity. R atrium and two cusps of the atrioventricular valve. L atrium and its auricle. Thoracic aorta. Inferior vena cava. Coronary sinus.

Valve Development

AV Canal Division (Superior View).jpg

AV Valves.jpg

Development of the mitral and tricuspid valves

  • Week 7 to 10 (GA) - sculpted from the ventricular wall valve leaflets form attached by chordae tendineae insert into small muscles attached to the ventricle wall: the papillary muscles.
    • left AV valve has anterior and posterior leaflets and is termed the bicuspid or mitral valve.
    • right AV valve has a third, small septal cusp and thus is called the tricuspid valve. These concepts are depicted on the right.
  • development of cardiac valves, particularly the process of epithelial to mesenchymal transformation (EMT)
  • expansion of endocardial cushion tissue and remodelled to form thin sheets.
    • cushion proliferation, is limited by neurofibromin acting through the inhibition of Ras signalling as well as Smad6 which interferes with TGFβ signalling.
Semilunar Valves.jpg

Development of the semilunar valves

Semilunar Cusps.jpg

Development of the semilunar cusps

Aortic and pulmonary valves (semilunar valves)

  • formed from the bulbar ridges and subendocardial valve tissue.
  • primordial semilunar valve consists of a mesenchymal core covered by endocardium.
  • mechanisms of valve remodelling may involve apoptotic pathways.

Cardiac Conduction

  • Week 7 (GA) - SA node initially develops in the sinus venosus and then is incorporated into the RA.
  • AV node arises slightly superior to the endocardial cushions.

Cardiac Conduction System.jpg

Diagram of the adult cardiac conduction system

Embryonic Heart Rate

The heart rate data shown below is from a 1996 ultrasound study of normal successful human gestations (34-56 days GA) developmental stages.[1]

  • Week 5-6 (GA) Stage 9 to 10 - 2 mm embryo (gestational sac diameter of 20 mm) EHR at least 75 beats / minute
  • Week 6 (GA) Stage 11 to 12 5 mm embryo (gestational sac diameter of 30 mm) EHR at least 100 beats / minute
  • Week 8 (GA) Stage 16 - 10 mm embryo EHR at least 120 beats / minute
  • Week 9 (GA) Stage 18 - 15 mm embryo EHR at least 130 beats / minute

Links: Week 17 (GA) Fetal Heart Rate

Fetal Heart

Beyond the scope of this current talk.

Study using 3 and 4-dimensional fetal echocardiography between 12 and 41 weeks gestational age measured outflow tract angles.[2]

  • ductal arch and thoracic aorta angle decreased with age.
  • between the ductal arch and the aortic arch angle increased with age.
  • between the left outflow tract (LOT) and right outflow tract (ROT) angle increased with age.


Shown below are images showing the major Congenital Heart Disease (CHD). More details about the abnormality and the associated epidemiology and disease classification (ICD) can be seen by opening the table beside the image. Within the tables for the major CHDs, there are linked pages just about that abnormality.

About - The International Classification of Diseases (ICD)
The International Classification of Diseases (ICD) World Health Organization's classification used worldwide as the standard diagnostic tool for epidemiology, health management and clinical purposes. This includes the analysis of the general health situation of population groups. It is used to monitor the incidence and prevalence of diseases and other health problems. Within this classification "congenital malformations, deformations and chromosomal abnormalities" are (Q00-Q99) but excludes "inborn errors of metabolism" (E70-E90).
Links: ICD - XVII Congenital Malformations

CHD is a feature of many genetic abnormalities, the most relevant statistically would be Trisomy 21, but there are others that can be identified from the genetic links below.

Genetic Links: genetic abnormalities | maternal age | Trisomy 21 | Trisomy 18 | Trisomy 13 | Trisomy X | trisomy mosaicism | Monosomy | Fragile X | Williams | Alagille | Philadelphia chromosome | mitochondria | VACTERL | hydatidiform mole | epigenetics | Prenatal Diagnosis | Neonatal Diagnosis | meiosis | mitosis | International Classification of Diseases | genetics

Ventricular Septal Defect

Ventricular Septal Defect.jpg
About - Ventricular Septal Defect
The Ventricular Septal Defect (VSD)
  • Usually occurs in the membranous (perimembranous) rather than muscular interventricular septum, and is more frequent in males that females.
  • Perimembranous defects are located close to the aortic and tricuspid valves and adjacent to atrioventricular conduction bundle.
  • Growth failure of the membranous interventricular septum or endocardial cushions, resulting in a lack of closure of the interventricular foramen.
  • 30-50% close spontaneously; large VSDs result in dyspnoea and cardiac failure in infancy.
  • Epidemiology - 25% of CHD; more frequent in males.
  • ICD-10 Q21.0 Ventricular septal defect

Links: Ventricular Septal Defects | Search PubMed

Atrial Septal Defects

Atrial Septal Defect.jpg
About - Atrial Septal Defect
The Atrial Septal Defect (ASD)
  • Are a group of common (1% of cardiac) congenital anomolies defects occuring in a number of different forms and more often in females.
  • patent foramen ovale- allows a continuation of the atrial shunting of blood
    • in 25% of people a probe patent (allowing a probe to be passed from one atria to the other) foramen ovale exists.
  • ostium secundum defect
  • endocardial cushion defect involving ostium primum
  • sinus venosus defect - contributes about 10% of all ASDs and occurs mainly in a common and less common form. Common ("usual type") - in upper atrial septum which is contiguous with the superior vena cava. Less common - at junction of the right atrium and inferior vena cava.
  • common atrium

ICD-10 Q21.1 Atrial septal defect Coronary sinus defect Patent or persistent: foramen ovale ostium secundum defect (type II) Sinus venosus defect

Treatment: The surgical repair requires a cardiopulmonary bypass and is recommended in most cases of ostium secundum ASD, even though there is a significant risk involved. Ostium primum defects tend to present earlier and are often associated with endocardial cushion defects and defective mitral or tricuspid valves. In such cases, valve replacement may be necessary and the extended operation has a considerable chance of mortality.

  • Increasingly closure by a transcatheter device closure has been applied.
  • Repair of atrial septal defects on the perfused beating heart (atrial septal defect size 2 cm - 4.5 cm) [3]

Links: Atrial Septal Defects | OMIM: Atrial Septal Defect | Search PubMed | Medline Plus - ASD Repair Video

Patent Ductus Arteriosus

Patent Ductus Arteriosus.jpg
About - Patent Ductus Arteriosus
* Patent ductus arteriosus (PDA), or Patent arterial duct (PAD), occurs commonly in preterm infants, and at approximately 1 in 2000 full term infants.
  • more common in females (to male ratio is 2:1).
  • Can also be associated with specific genetic defects, trisomy 21 and trisomy 18, and the Rubinstein-Taybi and CHARGE syndromes.
  • The opening is asymptomatic when the duct is small and can close spontaneously (by day three in 60% of normal term neonates).
  • The remainder are ligated simply and with little risk, with transcatheter closure of the duct generally indicated in older children.
    • The operation is always recommended even in the absence of cardiac failure and can often be deferred until early childhood.
  • ICD-10 Q25.0 Patent ductus arteriosus Patent ductus Botallo Persistent ductus arteriosus

Links: Patent Ductus Arteriosus |Search PubMed

Tetralogy of Fallot

Tetralogy of Fallot.jpg
About - Tetralogy of Fallot
  • Named after Etienne-Louis Arthur Fallot (1888) who described it as "la maladie blue" and is a common developmental cardiac defect.
  • The syndrome consists of a number of a number of cardiac defects possibly stemming from abnormal neural crest migration.
  • ICD-10 Q21.3 Tetralogy of Fallot Ventricular septal defect with pulmonary stenosis or atresia, dextroposition of aorta and hypertrophy of right ventricle.

Links: Gene expression in cardiac tissues from infants with idiopathic conotruncal defects | Search PubMed

Hypoplastic Left Heart

Hypoplastic Left Heart.jpg
About - Hypoplastic Left Heart
  • Characterized by hypoplasia (underdevelopment or absence) of the left ventricle obstructive valvular and vascular lesion of the left side of the heart.
  • ICD-10 Q23.4 Hypoplastic left heart syndrome Atresia, or marked hypoplasia of aortic orifice or valve, with hypoplasia of ascending aorta and defective develop-ment of left ventricle (with mitral valve stenosis or atresia).

Links: Search PubMed

Double Outlet Right Ventricle

Double Outlet Right Ventricle.jpg
About - Double Outlet Right Ventricle
  • De-oxygenated blood enters the aorta from the right ventricle and is returned to the body.
  • ICD-10 Q20.1 Double outlet right ventricle Taussig-Bing syndrome
Links: Search PubMed

Tricuspid Atresia

Tricuspid Atresia.jpg
About - Tricuspid Atresia
  • Blood is shunted through an atrial septal defect to the left atrium and through the ventricular septal defect to the pulmonary artery.
    • The shaded arrows in the cartoon indicate mixing of the blood.
  • ICD-10 Q22.4 Congenital tricuspid stenosis Tricuspid atresia
  • Fontan Procedure - a surgical procedure developed by Fontan and Baudet (1971) to restore a circulation in patients with tricuspid atresia.

Links: Search PubMed | Fontan procedure


Dextrocardia heart position.jpg

Dextrocardia anatomical heart position[4]


Dextrocardia (postnatal 1 year old)[4]

About - Dextrocardia
  • Initial malrotation of the heart tube bending left instead of right. Results in heart and greater vessels reversed.
  • Can also occur with situs invertus, where viscera are transposed LR.
  • Anatomical left-right normal asymmetry is called situs solitus. The alternative heterotaxy can be either randomization (situs ambiguus) or a complete reversal (situs inversus) of normal organ position.

Links: Chicken Abnormal Heart Movie | Search PubMed

Abnormalities of Conducting System

Also variously called the cardiac conduction system (CCS), cardiac pacemaking and conduction system (CPCS), or atrioventricular conduction system (AVCS). Recently animal models (CCS-lacZ transgenic mouse) have helped identify key processes in the development of this specialized conduction system.

"Known arrhythmogenic areas including Bachmann's bundle, the pulmonary veins, and sinus venosus derived internodal structures, demonstrate lacZ expression." (Jongbloed et al, 2004)

Long QT Syndrome

Congenital long QT syndrome (LQTS) is a group of rare genetic disorders with prolonged ventricular repolarization and a risk of ventricular tachyarrhythmias. Cause is mutations in genes encoding either cardiac ion channels or channel interacting proteins.

Search NCBI Bookshelf: Congenital long-QT syndrome

Links: Search PubMed

Magnetic Resonance Imaging

The following movies show aspects of heart development from mid-embryonic to the end of embryonic development.[5] Original image resolution of the scans ranges from 30-150 microns/pixel.

Gestational Age

Image source: The Kyoto Collection embryo MRIs are reproduced with the permission of Prof. Shige Yamada, Cecilia Lo and Kohei Shiota. This material is provided for educational purposes only and cannot be reproduced electronically or in writing without permission. MRI Atlas of Human Embryo Ref:<pubmed>20503356</pubmed>| PMC3401072

Further Online Reading

Cardiovascular Links: cardiovascular | Heart Tutorial | Lecture - Early Vascular | Lecture - Heart | Movies | 2016 Cardiac Review | heart | coronary circulation | heart valve | heart rate | Circulation | blood | blood vessel | blood vessel histology | heart histology | Lymphatic | ductus venosus | spleen | Stage 22 | cardiovascular abnormalities | OMIM | 2012 ECHO Meeting | Category:Cardiovascular
Historic Embryology - Cardiovascular 
1902 Vena cava inferior | 1905 Brain Blood Vessels | 1909 Cervical Veins | 1909 Dorsal aorta and umbilical veins | 1912 Heart | 1912 Human Heart | 1914 Earliest Blood-Vessels | 1915 Congenital Cardiac Disease | 1915 Dura Venous Sinuses | 1916 Blood cell origin | 1916 Pars Membranacea Septi | 1919 Lower Limb Arteries | 1921 Human Brain Vascular | 1921 Spleen | 1922 Aortic-Arch System | 1922 Pig Forelimb Arteries | 1922 Chicken Pulmonary | 1923 Head Subcutaneous Plexus | 1923 Ductus Venosus | 1925 Venous Development | 1927 Stage 11 Heart | 1928 Heart Blood Flow | 1935 Aorta | 1935 Venous valves | 1938 Pars Membranacea Septi | 1938 Foramen Ovale | 1939 Atrio-Ventricular Valves | 1940 Vena cava inferior | 1940 Early Hematopoiesis | 1941 Blood Formation | 1942 Truncus and Conus Partitioning | Ziegler Heart Models | 1951 Heart Movie | 1954 Week 9 Heart | 1957 Cranial venous system | 1959 Brain Arterial Anastomoses | Historic Embryology Papers | 2012 ECHO Meeting | 2016 Cardiac Review | Historic Disclaimer


  1. <pubmed>8921130</pubmed>
  2. <pubmed>17384040</pubmed>| MC2190734 J Ultrasound Med.
  3. <pubmed>19876418</pubmed>
  4. 4.0 4.1 <pubmed>19142355</pubmed>| Arq Bras Cardiol.
  5. <pubmed>20503356</pubmed>| PMC3401072 | MRI Atlas of Human Embryo

Additional References

Online Textbooks

Search Bookshelf heart development


<pubmed>21940548</pubmed> <pubmed>17224285</pubmed>| PMC1858673 <pubmed></pubmed>


<pubmed></pubmed> <pubmed></pubmed> <pubmed></pubmed> <pubmed>9475206</pubmed>

Search Pubmed

Search Pubmed heart development

External Links

External Links Notice - The dynamic nature of the internet may mean that some of these listed links may no longer function. If the link no longer works search the web with the link text or name. Links to any external commercial sites are provided for information purposes only and should never be considered an endorsement. UNSW Embryology is provided as an educational resource with no clinical information or commercial affiliation.

  • Cardiovascular Ultrasound is an open access, peer-reviewed, online journal covering clinical, technological, experimental, biological, and molecular aspects of ultrasound applications in cardiovascular physiology and disease. Search - Fetal

Glossary Links

Glossary: A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | Numbers | Symbols | Term Link

Cite this page: Hill, M.A. (2024, May 28) Embryology Fetal ECHO Meeting 2012. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Fetal_ECHO_Meeting_2012

What Links Here?
© Dr Mark Hill 2024, UNSW Embryology ISBN: 978 0 7334 2609 4 - UNSW CRICOS Provider Code No. 00098G