Pedi CV Flashcards
4th-8th week of gestation. Major cause of death related to birth defects 0-1y. Associated with certain syndromes: Trisomy 21, DeGeorge, Apert, Cri du chat, Noonan
Congenital CV Disorders
Common causes: Infection Autoimmune response Environment? Heredity
Acquired CV Disorders
Maternal: infection, substance use in pregnancy, diabetes.
Genetic: History of CHD in other family members, syndromes, other anomalies, congential or chromosomal
Risk factors of Pediatric Cardiovascular Disorders
Gas exchange shifts to lungs. Umbilical cord cut. Lungs inflate (PVR decreases), SVR increases, Blood to LA increases. Flow through fetal shunts reversed: PFO closes d/t L sided pressure. PDA closes within 24-48 hours
Newborn (pulmonary) Circulation
INCREASED PULMONARY BLOOD FLOW. ACYANOTIC. Ductus arteriosus fails to close (usually 2-3 days). Blood from aorta to PA. Common; 5-10% of infants with CHD.
Treatment: IV ibuprofen, indomethacin to stimulate closure in premature infants. Surgical ligation of PDA.
Goals: Prevent pulmonary hypertension, vascular issues
Patent Ductus Arteriosus (PDA)
INCREASED PULMONARY BLOOD FLOW. ACYANOTIC. L TO R SHUNT. Hole in atrial septum. Oxygenated blood from L atrium mixes with non oxygenated blood with R atrium. Common; 6-10% of CHD. May hear murmur. Echo may show dilated R ventricle.
Treatment: Rest, nutrition, surgical repair: patch placed.
Goals: Prevent adult complciations; stroke, arrythmias, pulm htn
Atrial Septal Defect (ASD)
INCREASED PULMONARY BLOOD FLOW. ACYANOTIC. L TO R SHUNT. Hole in ventricular septum. Oxygenated blood from L ventricle to non-oxygenated blood in R ventricle. Common; 20-25% of CHD.
Treatment: Digoxin- controls rate and rhythm. Lasix- diuresis. ACE inhibitors- decrease SVR, aortic pressure and shunting. Surgical: temporary branding of pulmonary vessels (reduce flow to lungs), patch at 3-12 mo.
Goals: Prevent heart failure and pulm htn (in moderate to large VSDs)
Ventricular Septal Defect (VSD)
OBSTRUCTED BLOOD FLOW. ACYANOTIC. Narrowing of the descending aorta. 5-8% of CHD. Once PDA closes, perfusion to lower extremeties impaired. 4-extremity Bps (higher in arms than legs). Treatment: Prostaglandin to keep PDA open (perfuse kidneys and lower extremities). Diuretics, O2, inotropes. Surgical repair- end to end anastomosis.
Goals: Prevent shock, heart failure, renal failure, NEC
Coarctation of the Aorta
OBSTRUCTED BLOOD FLOW. ACYANOTIC. Narrowing of the aortic valve. Systemic blood flow compromised.
Treatment: Surgical repair/balloon valvuloplasty/Ross, bacterial endocarditis prophylaxis, exercise restrictions
Aortic Stenosis
OBSTRUCTED BLOOD FLOW. ACYANOTIC. L side of the heart severely underdeveloped (mitral & aortic valves ascending aorta). Decreased force of L ventricle contraction. Reduced systemic blood flow. Open PDA allows R-L shunting; mixing in R ventricle. Most common cause of death among neonates with CHD. R ventricle dilation/hypertrophy.
Treatment: Prostaglandin to keep PDA open and maintain systemic perfusion. Surgical repair- Norwood- 3 stage repair. 1) RV converted to systemic effects. 2.) Separate pulm/systemic circulation
Hypoplastic Left Heart Syndrome
DECREASED PULMONARY BLOOD FLOW. CYANOTIC. OBSTRUCTION OF FLOW TO LUNGS. R TO L SHUNT. Most common cyanotic heart defect in infants. Four (sometimes five) defects: Pulmonic stenosis, right ventricular hypertrophy, VSD (sometimes ASD), overriding aorta. Progressive cyanosis “tet spells” - knee to chest (decreases return to heart). 10% of CHD.
Treatment: Surgical repair- BT shunt. Close VSD/ASD. Relieve pulmonary stenosis.
Goals: Manage hypercyanotic episodes, prevent metabolic acidosis.
Tetralogy of Fallot
DECREASED PULMONARY BLOOD FLOW. CYANOTIC. OBSTRUCTION OF BLOOD FLOW TO LUNGS (R to L SHUNT). Flow from R ventricle to pulmonary artery obstructed. 3 types, severity can vary: subvalvular, valvular, supravalvular. 2nd most common CHD, 5-10%.
Treatment: Surgical repair: (depend on type). Valvuloplasty via cardiac cath; patch angioplasty. Lifelong prophylaxis for infective endocarditis. Goals: prevent heart failure.
Pulmonic Stenosis
DECREASED PULMONARY BLOOD FLOW. OBSTRUCTION OF BLOOD FLOW TO LUNG. CYANOTIC. Pulmonic valve underdeveloped or closed. Blood cannot get to lungs for oxygenation. Cyanosis immediately. RV and tricuspid valve small, dysfunctional. ASD usually present (R-L shunting)
Treatment: Must be managed at birth- Prostaglandins immediately to keep PDA open. Goals: Manage hypercyanotic episodes. Prevent metabolic acidosis.
Pulmonary Atresia
DECREASED PULMONARY BLOOD FLOW. CYANOTIC. OBSTRUCTION OF BLOOD FLOW TO LUNGS. Tricuspid valve did not form- no flow from R atrium to R ventricle (CYANOSIS). ASD present (R-L shunt). R ventricle hypoplastic; R atrium enlarged/hypertrophic. L ventricle overloaded- enlarged, fx decreases. 1 in 10,000 babies. Treatment: PGA immediately to keep PDA open. 3 surgeries to establish pulmonary circulation: BT shunt, Glenn, Fontan. Prophylaxis for endocarditis. May require anticoaglant treatment.
Goals: Prevent hypoxemia
Tricuspid Atresia
Gas exchange in the placenta. Oxygenated blood via the umbilical vein. High PVR (lungs not used yet). Placenta and PDA = low SVR. IVE to RA to Foramen Ovale to LA. SVC to RA to RV to Ductus Arteriosus to descending aorta (lungs are bypassed)
Fetal Circulation
ability to produce contraction
Contractility
Amount of blood pumped from L ventricle each minute
Cardiac Ouput
How much blood pumped with each beat
Stroke Volume
How much blood in heart/ventricle at end of diastole
Preload
How much pressure in great vessels
Afterload