Congenital Heart Disease Most common type of heart disease among children a) ~ 1% of live births b) most causes unknown i) ~ 10% genetic - e.g., trisomy 21 (Down syndrome) - congenital defect in parent or sibling is greatest risk factor
Types:a) L to R shuntb) R to L shuntc) obstructions 1.- L to R shuntsa) ASD, VSD, PDAi) pulmonary blood flow (ASD)- NO cyanosisb) RV pressures and Vol. (VSD,PDA)i) hypertrophyii) PVR (vasoconstriction)- to prevent edema
c) Over time PVR to that of SVRi) reverses shunt (cyanosis)2.- R to L shunta) pulmonary blood flowi) Cyanosis “blueness” of skinb) examples:i) tetralogy of Fallot ii) great vessel transpositioniii) truncus arteriosusiv) tricuspid atresiav) anomalous pulmonary venous connection
c) long standing cyanosis is associated with “clubbing” of the tips of the fingers and toes
3.- Obstructions (of flow)a) coarctation of the aortab) valvular stenosisi) aorticii) pulmonary c) complete obstruction is called “Atresia”
Left to Right Shunts Most common: a) VSD, ASD, PDA and AVSD
i) VSD most common - close spontaneously (50%) ii) ASD usually not symptomatic before 30 yrsiii) DA remains open after birth- ~ 90% occur as isolated anomaly - reversal of flow with PVR causes cyanosis- PGE will maintain DAcardiac defects such as obstructive disease iv) complete atrioventricular canal defect- all 4 chambers freely communicate (Down syndrome)
Right to Left Shunts Tetralogy of Fallot a) Most common form of cyanotic congenital heart disease Defects: a) VSD b) Pulmonary artery stenosis i) determines clinical outcome c) aorta that overrides VSD d) RV hypertrophy
Tetralogy of Fallot (TOF) Michael P. D'Alessandro, M.D. Peer Review Status: Internally Peer Reviewed
Clinical Presentation: a) The onset and degree of cyanosis depends on: i) severity of the pulmonary obstruction ii) the size of the shunt. b) Cyanosis is usually not seen until 3- 6 months of age. c) The cyanosis is due to right ventricle outflow obstruction causing unoxygenated blood through the VSD.
Transposition of the Great Arteries(TGA)a) aorta arises from RVi) is anterior and to the right of the pulmonary arteryb) pulmonary artery arises from LVc) total separation of pulmonary and systemic circulationsi) need a shunt to survive following birth- VSD stable shunt
- PDA, foramen ovale unstable shunt (close quickly after birth) need surgery the aorta originates from the right ventricle, so most of the blood returning to the heart from the body is pumped back out without first going to the lungs. the pulmonary artery originates from the left ventricle, so that most of the blood returning from the lungs goes back to the lungs again
Truncus Arteriosus Failure of separation into aorta and pulmonary arterya) results in single great arteryi) receives blood from both ventricles- early systemic cyanosisb) accompanying VSDc) pulmonary blood flowi) danger of irreversible pulmonary hypertension
Tricuspid Atresia Clinical Presentation: a) Cyanosis is almost always present at birth and is progressive. b) Etiology/Pathophysiology: i) Due to absence of the tricuspid valve. This leads to an interatrial right to left shunt, usually through a patent foramen ovale.
Total Anomalous Pulmonary Venous Connection (TAPVC) No pulmonary veins directly join LA a) drain into left innominate vein or coronary sinus b) PV drain into RA ASD or foramen ovale always present a) allows PV blood to enter LA b) R to L shunt Volume and pressure hypertrophy of RV
Obsttructive Congenital Anomalies Coarctation of the Aorta Narrowing Males 2:1 vs. female a) females with Turners frequently have coarctation 2 types: a) infantile (with PDA; poor outcome) i) prior to PDA - symptoms early in life - cyanosis of lower body
b) adult (without PDA) i) most children asymptomatic until late in life ii) hypertension in upper extremities iii) hypotension in lower extremities LV hypertrophy