Congenital Heart Disease 2 Flashcards
congestive heart failure - overview & causes in adults vs. infants
*defined as state where the heart is unable to pump blood/oxygen at rate needed by the body’s demands
*several mechanisms:
-weak heart (most adult pts)
-strong but inefficient heart (infants with congenital heart disease, esp shunt lesions)
CHF - compensatory changes
*hypovolemia detected by the body leads to:
-renal salt & water retention
-increased catecholamine levels
-cardiac remodeling
causes of CHF in pediatrics - by age group
*neonates: obstructive lesions (coarctation, aortic stenosis)
*infants: shunt lesions (VSD, PDA)
*older children/adolescents: cardiomyopathy
CHF physical exam in pediatrics
*vital signs - HR, RR, BP
*respiratory status (usually tachypneic)
*distal perfusion (cap refill, temperature)
*pulses (often diminished, but could be bounding)
*hepatomegaly
*extracardiac malformations
atrioventricular septal defect - aka
*endocardial cushion defect
*AV canal
atrioventricular septal defect - consists of
- ostium primum ASD
- VSD
- common AV valve
atrioventricular septal defect (AVSD) - physiology
*behaves like a large VSD:
-left to right shunt
-congestive heart failure (poor feeding/poor weight gain, pulmonary edema & respiratory distress, diaphoresis)
*treatment involves surgical repair at 4-6 months of age
atrioventricular septal defect & trisomy 21
*40-50% of AVSD patients will have trisomy 21
*45% of children with trisomy 21 have a heart defect
*at least 25% of trisomy 21 patients have an AVSD
hypoplasia - defined
*developed, but smaller than normal
atresia - defined
*never formed at all
*valve atresia = door never opened; a solid shelf exists instead of a functional valve
stenosis - defined
*only opens partially
*obstructed
acyanotic congenital heart defects - obstructive lesions
*pulmonic stenosis (PS)
*aortic stenosis (AS)
*coarctation of the aorta
pulmonic/aortic stenosis - murmur
*murmur due to turbulent blood flow through narrowed valve orifice
*higher pressure gradient, higher pitch
*thrill = vibration felt over the skin, indicating severe turbulence
pulmonic/aortic stenosis - clinical findings
*mild to moderate pulmonic/aortic stenosis: asymptomatic
*some findings include:
-shift in PMI
-RVH on EKG
*severe pulmonary stenosis = CYANOSIS
*sever aortic stenosis = SHOCK (cardiogenic)
pulmonic/aortic stenosis - physiology
*higher ventricular pressures need to overcome valve stenosis
pulmonic/aortic stenosis - treatment
*neonate: prostaglandins (to maintain PDA as a second source) until surgery
*no treatment needed for mild to moderate aortic or pulmonic stenosis
*if severe stenosis or sick infant:
-valvuloplasty (catheter placement with balloon to expand the valve)