Jar of Hearts
The cardiogenic field develops from this type of embryonic tissue
What is splanchnic mesoderm?
This heart tube chamber is formed of a small median part called body and 2 lateral horns. After looping, it opens through the primitive atrium through a sinoatrial orifice.
This structure becomes the adult coronary sinus
What is the left horn of the sinus venosus?
The timeframe for the partitioning of the primordial heart is
What is the beginning of the 4th week and end of the 5th week?
This anomaly is characterized by the heart lying on the right side of the thorax
What is Dextrocardia?
There are 2 types of folding that occurs when the heart endocardial tubes change from 2 endocardial tubes to one single tube. The two folds are called
What is lateral folding and cephalo-caudal folding?
1. Lateral folding: where the 2 tubes are brought together forming the primitive heart
2. Cephalo-caudal folding: the primitive heart tube is situated into the thoracic region
During dextral looping, the bublus cordis moves ventral and to the right while the primitive ventricle moves ventral and to the left. This movement is responsible for a particular shaped heart tube. NAME THAT SHAPE!
What is U-shaped heart tube?
(for completeness: primitive atrium moves posterior and superior to them, and into it the sinus venosus will open which forms an s-shaped heart tube)
This vein is the only vein that remains as a vein, but is then called the "oblique vein of the left atrium" which opens in the coronary sinus
What is the left common cardinal vein?
These mesenchymal proliferations of the AV canal approach each other, fusing to form the septum intermedium (separates L and R canal- partially separating the primordial atrium and ventricle)
What are the endocardial cushions?
In this congenital anomaly the oblique passage between septum primum and septum secundum is closed functionally (by increased pressure in LA) but remains patent anatomically, so that a probe can be passed through it. (No health issues).
What is Probe Patent Foramen Ovale?
Blood flow begins during this week and can be visualized by a doppler ultrasound
What is the 4th week (22 days)?
Deoxy: Common cardinal (from body), Vitelline (from yolk sac)
Oxy: Umbilical vein (from placenta)
Name the primitive structures that form the Sinus Venarum (posterior smooth part of the right atrium)
What are the right horn and body of sinus venosus?
The primitive atrium is divided by the interatrial septum into right and left atria. The interatrial septum is formed by these 3 septa
What are the septum primum, septum secondum, septum intermedium?
This congenital anomaly comprises 70% of atrial septal defects. It is either due to excessive resorption of septum primum or shortening/absence of septum secondum
What is Ostium Secondum Defects?
When the dilatations form in the heart tube, it becomes divided into 5 communicating chambers. From cranial to caudal, the 5 chambers are
Cranial to caudal:
truncus arteriosus (outflow part- arterial end of heart tube)
bulbus cordis
primitive ventricle
primitive atrium
sinus venosus (inflow part - venous end of heart tube)
The smooth part of the left atrium is derived from this embryonic structure
What is the absorbed part of the pulmonary veins?
The umbilical veins are formed into remodeling due to gradual invasion by the liver. In the remodel, it loses it's communication with the sinus horns and forms a network with the right vitelline vein (now the superior part of IVC). This remodeled connection is a bypass to the IVC containing pure oxy-blood from the placenta. This important bypass is called the
What is the ductus venous?
During formation of the interatrial septum, the septum secondum does not fuse to the septum primum but covers it, forming this important oblique passageway
What is the Foramen Ovale?
(for completeness: fossa ovalis is the lower part of septum primum and the limbus is the lower crescentic margin of septum secondum)
In this congenital anomaly there is complete failure of fusion of ventral and dorsal endocardial cushions. The atrial and ventricular components are separated by abnormal valve leaflets in the single AV orifice. It is accompanied by ASD and VSD
What is Persistent AV Canal?
During dextral looping the sinus venosus and primitive atrium will form this adult heart chamber
What is the atrium? (will be behind and above)
(for completeness: primitive ventricle + bulbus cordis form the adult ventricle --> will be in front and below)
Name the 3 immediate changes to the heart after birth:
What is the:
1. establishment of pulmonary circulation
2. functional closure of foramen ovale
3. functional closure of ductus arteriosus
The SA orifice (seen inside the cavity of sinus venosus) is form of a right and left valve that unite cranially forming the 'Septum Spurium' to the right of the interatrial septum. The fate of the right valve is ultimately to form these structures (3)
What are the Crista Terminalis, IVC and Coronary Sinus valves?
The rough (trabeculated) anterior part (pectinate muscles) of the right atrium are derived from this primordial structure
What is the right half of the common primordial atrium?
In this congenital anomaly there is complete agenesis of the tricuspid valve. It is associated with patent foramen ovale, VSD, atrophy of RV and hypertrophy of LA and LV
What is tricuspid atresia?