30 Shunts

  • ASD: RA and LA
  • VSD: RV and LV
  • PDA: PA and Ao

  • nl pressure always higher in left
  • result: if there's connection, usually left to right flow

  • no cyanosis at birth

  • epo release

VSD

  • tiny hole: restrict the flow, loud murmur, asymptomatic
  • large hole: not loud murmur but symptoms later in life

ASD

  • major consequence: add volume to right side of heart
  • increased flow across PV/TV causes systolic ejection murmur

  • shun run: take samples of different chambers to see O2 sat
  • ASD: step up at RA O2 sat because of blood mixing
  • VSD: step at at RV

Secundum

  • located in middle of wall: mid septum

Primum

  • left: septum primum fusion with EDC
  • right: non fusion, ASD
  • seen in endocardial cushion defects, collective defects in down syndrome

  • hole located lower

PDA

  • constriction of smooth muscle closes

  • differential: cyanosis in lower extremities but not upper, if untreated for years

  • blood drops much more during diastole to create wider pulse pressure

  • tetralogy/pulmonary atresia: cyanotic baby because not enough blood to lungs
  • alprostadil used to drive blood from aorta to PA

Others

  • shunt: blood shunted from left to right

  • very small shunting: no HF/eisenmenger
  • echo: RA on left, LA on right