fetal circulation and congenital heart disease

•Pressure gradient L:R •Flow from L - R •May lead to RAH and RVH •Typically asymptomatic •Pulmonary HTN late finding

atrial septal defect

umbilical arteries carry _____ blood

deoxygenated

Begins to close within first day of life

ductus arteriosus

Directs blood from pulmonary artery to aorta

ductus arteriosus

is a short blood vessel that connects the pulmonary artery to the aorta in the developing fetus. It is normally open only in a developing fetus.

ductus arteriosus

This shunt effectively bypasses the liver

ductus venosus

a shunt that allows oxygenated blood in the umbilical vein to bypass the liver and is essential for normal fetal circulation. Blood becomes oxygenated in the placenta and travels to the right atrium via umbilical veins through the this, then to the inferior vena cava.

ductus venosus

Blood entering the RT atrium flows across this shunt into the LT atria (RT → LT shunt)

foramen ovale

an aperture in the muscular tissue between the left and right atrium that allows blood to cross the atria and bypass pulmonary circulation during fetal development

foramen ovale

•Narrowed lumen of the aorta •70-80% bicuspid Ao valve •Related to closure of the ductus arteriosus •Upper extremity hypertension •Weak lower extremity pulses •Cool mottled lower extremity skin

coarctation of the aorta

Blood ejected from LT heart is preferentially delivered to ____ and ___ extremities

head upper

fetal circulation has high or low cardiac output?

high

umbilical veins carry _____ blood

oxygenated

Continuous machinery type murmur of the upper LT sternal border

patent ductus arteriosus

This structure provides oxygen and nutrients to your growing baby and removes waste products from your baby's blood.

placenta

where does oxygenation occur in the fetus?

placenta

Ductus arteriosus remains patent due to active relaxation in the presence of what substance?

prostaglandin E2

High fetal ______ ______ resistance

pulmonary vascular

•Congenital narrowing of Pulmonary outflow tract

pulmonic stenosis

•Increase afterload of the RV •Incomplete ejection and RV output •RVH may lead to RAH

pulmonic stenosis

•WORST CASE: RAH and RA pressure may re-open the foramen ovale •Shunt RT - LT

pulmonic stenosis

•Most common cyanotic defect •Symptoms depend upon size of VSD and degree of pulmonary stenosis •Degree of cyanosis depends upon vessel resistance

tetralogy of fallot

Large VSD + overriding Aorta + pulmonic valve stenosis + RVhypertrophy

tetralogy of fallout

•Approximately 50% of blood delivered to the aorta reaches the placenta via two _____ _____

umbilical arteries

•Most common congenital heart abnormality: 25-30% •LT to RT shunting •As pulmonary resistance decreases, symptoms increase •LT sided Failure

ventricular septal defect

•Blood is oxygenated in _____ and returned via the singular ____ ____

villi umbilical vein

fetal circulation has ____ arteries and ____ veins

2 1

low oxygen tension in fetal circulation increases ____ oxygen binding

HgF