Search results
Results From The WOW.Com Content Network
The fetal circulation is composed of the placenta, umbilical blood vessels encapsulated by the umbilical cord, heart and systemic blood vessels. A major difference ...
Persistent fetal circulation is a condition caused by a failure in the systemic circulation and pulmonary circulation to convert from the antenatal circulation pattern to the "normal" pattern. Infants experience a high mean arterial pulmonary artery pressure and a high afterload at the right ventricle.
There are three stages of fetal development. The first stage is the germinal stage begins at conception and is the shortest stage. The second stage is the embryonic stage which begins around the third week of pregnancy and ends at the eighth week. The final stage is the fetal stage which begins at the ninth week of pregnancy and lasts until birth.
The "E" series of prostaglandins are responsible for maintaining the openness of the ductus arteriosus (by dilation of vascular smooth muscle) throughout the fetal period. [3] Prostaglandin E2 (PGE 2 ), produced by both the placenta and the DA itself, is the most potent of the E prostaglandins, but prostaglandin E1 (PGE 1 ) also has a role in ...
The sinus venosus connects to the fetal circulation. The heart tube elongates on the right side, looping and becoming the first visual sign of left-right asymmetry of the body. Septa form within the atria and ventricles to separate the left and right sides of the heart. [3]
All of these cardiovascular system changes result in the adaptation from fetal circulation patterns to an adult circulation pattern. During this transition, some types of congenital heart disease that were not symptomatic in utero during fetal circulation will present with cyanosis or respiratory signs.
Fetal programming, also known as prenatal programming, is the theory that environmental cues experienced during fetal development play a seminal role in determining health trajectories across the lifespan. Three main forms of programming that occur due to changes in the maternal environment are:
The first and second arches disappear early. A remnant of the 1st arch forms part of the maxillary artery, [3] a branch of the external carotid artery. The ventral end of the second develops into the ascending pharyngeal artery, and its dorsal end gives origin to the stapedial artery, [3] a vessel which typically atrophies in humans [4] [5] but persists in some mammals.