Pediatric Nursing: Congenital Heart Disease Part VII
Cardiac structure and function
Cardiovascular disorders in children are divided in to two major groups: Congenital
Cardiac Defects and Acquired Heart Disorders.
Congenital heart defects are anatomic abnormal it is present at birth that result in
abnormal cardiac function.
The clinical consequences of congenital heart defects fall into two broad categories:
Congestive Heart Failure and Hypoxemia.
Acquired cardiac disorders refer to disease processes or abnormalities that occur after
birth and can be seen in the normal heart or in the presence of congenital heart
defects. They result from various factors, including infection, autoimmune
responses, environmental factors, and familial tendencies.
The heart and other components of the circulatory system (blood, blood vessels,
lymph) begin to develop during the fourth week of gestation and are completed by
the eighth week.
1
, Pediatric Nursing: Congenital Heart Disease Part VII
Fetal circulation
The fetal brain requires highest oxygen concentration. The lungs are essentially
nonfunctional, and the liver is only partially functional: therefore, less blood is
needed in these organs in fetal life.
Blood carrying oxygen and nutritive materials from the placenta enters the fetal
system through the umbilicus via )the large umbilical vein(. The blood then travels to
the liver, where it divides; part of the blood enters the portal and hepatic circulation
of liver; and the remainder travels directly to the inferior vena cava (IVC) by way of
the ductus venosus. Because of the higher pressure of blood entering the RA from the
IVC it is directed posteriorly in a straight pathway across the RA and through the
foramen ovale to the LA. Oxygenated blood enters the LA and LV to be pumped
through the aorta to the head and upper extremities. Blood from the head and upper
extremities entering the RA from the superior vena cava (SVC) is directed downward
through the tricuspid valve into the RV. From there it is pumped through the
pulmonary artery, where the major portion is shunted to the descending aorta via the
ductus arteriosus. A small amount flows to and from the nonfunctioning fetal lungs.
Blood is returned to the placenta from the descending aorta through the placenta from
the descending aorta through the two umbilical arteries.
2
Cardiac structure and function
Cardiovascular disorders in children are divided in to two major groups: Congenital
Cardiac Defects and Acquired Heart Disorders.
Congenital heart defects are anatomic abnormal it is present at birth that result in
abnormal cardiac function.
The clinical consequences of congenital heart defects fall into two broad categories:
Congestive Heart Failure and Hypoxemia.
Acquired cardiac disorders refer to disease processes or abnormalities that occur after
birth and can be seen in the normal heart or in the presence of congenital heart
defects. They result from various factors, including infection, autoimmune
responses, environmental factors, and familial tendencies.
The heart and other components of the circulatory system (blood, blood vessels,
lymph) begin to develop during the fourth week of gestation and are completed by
the eighth week.
1
, Pediatric Nursing: Congenital Heart Disease Part VII
Fetal circulation
The fetal brain requires highest oxygen concentration. The lungs are essentially
nonfunctional, and the liver is only partially functional: therefore, less blood is
needed in these organs in fetal life.
Blood carrying oxygen and nutritive materials from the placenta enters the fetal
system through the umbilicus via )the large umbilical vein(. The blood then travels to
the liver, where it divides; part of the blood enters the portal and hepatic circulation
of liver; and the remainder travels directly to the inferior vena cava (IVC) by way of
the ductus venosus. Because of the higher pressure of blood entering the RA from the
IVC it is directed posteriorly in a straight pathway across the RA and through the
foramen ovale to the LA. Oxygenated blood enters the LA and LV to be pumped
through the aorta to the head and upper extremities. Blood from the head and upper
extremities entering the RA from the superior vena cava (SVC) is directed downward
through the tricuspid valve into the RV. From there it is pumped through the
pulmonary artery, where the major portion is shunted to the descending aorta via the
ductus arteriosus. A small amount flows to and from the nonfunctioning fetal lungs.
Blood is returned to the placenta from the descending aorta through the placenta from
the descending aorta through the two umbilical arteries.
2
