Congenital Defects Flashcards
When do congenital heart defects usually arise? What do they usually result in?
Arise during embryogenesis (usually weeks 3 through 8) seen in 1% of live births. Often result in shunting between left (systemic) and right (pulmonary) circulations.
How do defects with right-to-left shunting usually present?
As cyanosis shortly after birth
How do defects with left-to-right shunting present?
May be asymptomatic at birth but the shunt can eventually reverse. 1. Increased flow through the pulmonary circulation results in hypertrophy of pulmonary vessels and pulmonary hypertension 2. Increased pulmonary resistance eventually results in reversal of shunt, leading to late cyanosis (Eisenmenger syndrome) with right ventricular hypertrophy, polycythemia and clubbing
What is the most common congenital heart defect? What is it associated with?
Ventricular septal defect. Associated with fetal alcohol syndrome
What does Ventricular septal defect result in? What can large defects lead to? How i treated?s Ventricular septal defect
Left-to-right shunt. Large defects can lead to Eisenmenger syndrome. Treatment involves surgical closure.
What is the most common type of Atrial Septal Defect? What does it result in? What does it sound on auscultation? What is an important complication?
Ostium secundum (90% of cases). Results in left-to-right shunt and split S2 on ausculatation due to delayed closure of pulmonary valve from increased blood in right heart. Paradoxical emboli are an important complicaiton.
What is patent ductus arteriosis (PDA) What is it associated with? What does it result in?
Failure of ductus arteriosis to close. Associated with congenital rubella. Results in left-to-right shunt between the aorta and the pulmonary artery.
How does patent ductus arteriosis (PDA) present at birth? What can it lead to? How is it treated?
Asymptomatic at birth with continuous ‘machine-like’ murmur. May lead to Eisenmenger syndrome, resulting in lower extremity cyanosis. Treatment involves indomethacin which decreases Prostaglandin E (PGE) resulting in PDA closure.
What is the role of ductus arteriosus during development?
Normally shunts blood from the pulmonary artery to the aorta bypassing the lungs.
What is the role of ductus arteriosus during development?
Normally shunts blood from the pulmonary artery to the aorta bypassing the lungs.
What are the characteristics of Tetralogy of Fallot? What do you see on X-ray?
- Stenosis of right ventricular outflow tract 2. right ventricular hypertrophy 3. VSD 4. An aorta that overrides the VSD
‘Boot-shaped’ Heart on x-ray
How do patients with Tetralogy of Fallot respond to a cyanotic spell? How does it work?
Patinets learn to squat in response to a cyanotic spell. Increased arterial resistance decreses shunting and allows more blood to reach the lungs.
What is transposition of the great vessels? What is it associated with?
Characterized by pulmonary artery arising from the left ventricle and aorta arising from the right ventricle. Associated with maternal diabetes.
How does transposition of the great vessels present? What does it result in? How is it treated?
Presents with early cyanosis. Pulmonary and systemic circulation do not mix. Creation of shunt (allowing blood to mix) after birth is required for survivial. Results in hypertrophy of the right ventricle and atrophy of the left ventricle. PGE (Prostaglandin E) can be administered to maintain a Patent Ductus Arteriosus until surgery.
What is truncus arteriosus? How does it present?
Characterized by a single large vessel arising from both ventricles. Truncus fails to divide. Presents with early cyanosis; deoxygenated blood from Right Ventricle mixes with oxygenated blood from left ventricle before pulmonary and aortic circulation separate.
