Ch. 2 basic embryology & fetal circulation

ultimately, the sinus venosus forms the ___

Posterior portions of the atria

Pulmonary veins

Svc

Ivc

True or false

Prior to week 3, the heart consists of a pair of tubes situated on either side of the midline toward the caudal end of the embryo.

False

The interventricular sulcus divides the primitive ventricle and

bulbus cordis

The primitive atrium will divide into the

right and left atria

The bulbus cordis can be divided into three parts: the proximal bulbus cordis, conus cordis, and truncus arteriosus. Collectively, they form the

Apical portion of the right ventricle, ventricular outflow tracts, aorta, pulmonary artery

Ultimately, the left ___ aortic arch forms the definitive aortic arch.

Fourth

at 21-23 days, the heart tube is connected to the ___ at the cephalic end and the __ at the caudal end of the embryo.

Developing aortic arch system / Sinus venosus

within the atrioventricular canal, the __ grows and fuse until ultimately the atrioventricular canal is divided and the atrio ventricular valves are formed.

endocardial cushions

The sinus venosus and primitive atrium communicate via the

Sinoatrial orifice

Early in development, the __ is the only great vessel leaving the heart

Truncus arteriosus

Perforations develop in the septum primum resulting in the __

ostium secundum

The left and right ventricles are the result of trabecular expansions from two chambers within the bulboventricular loop, what are they?

Primitive ventricle and bulbus cordis

in the embryo, the left ventricle communicates with the right ventricle via

Primary interventricular foramen and secondary interventricular foramen

True or false

The interventricular septum stops growing once the atrial walls are no longer expanding

False

The trabecular interventricular septum is known as the ___ in the adult heart

muscular septum

The ___ interventricular septum forms where the secondary interventricular foramen was once located

membranous

The ___ is/are directly involved with the rotation and division of the truncus arteriosus

Bulbar ridges

The interatrial septum is formed by the septum primum and septum secundum; a remnant of the ___ forms a flap at the level of the foramen ovale that controls the flow between the right atrium and left atrium

Septum primum

By the end of week ___, the major development of the heart is complete

Seven

In the fetus, the ___ is responsible for the exchange of oxygen, carbon dioxide, nutrients, and waste products?

Placenta

True or false

The umbilical vein is the only vessel to carry enriched blood that has not mixed with depleted blood.

True

The majority of the blood in the umbilical vein is dumped into the ___ which connects directly to the IVC

Ductus venosus

True or false

The majority of the enriched blood that enters the right atrium passes on to the right ventricle and pulmonary artery

False

The umbilical artery O2 sat is approx

58%

Correct order of flow

Right atrium, foramen ovale, left atrium, left ventricle, aorta

Depleted blood returns to the heart via the

SVC

While performing an echo on a premature baby, what two findings are to be expected?

Patent ductus arteriosus & patent foramen ovale

What causes the foramen ovale to close?

Increased left atrial pressure

The remnant of the ductus arteriosus is called the

ligamentum arteriosum

Persistent feral circulation is the result of

Pulmonary hypertension and persistent right to left shunting across the PFO and PDA