147 Pathology of CHD

Question 1

ASD: Secundum type

Answer 1

Question 2

ASD types (4)

Answer 2

**Shunt flow now pressurized**

–PVR may rise, but less common (some pts may never show elevated pressures)

–Less rise in PVR (i.e. Eisenmenger syndrome uncommon)

Long-term complications:

•“right heart failure”

–Elevated RA pressure, impaired SVC/IVC return

–Lower extremity (dependent) edema, ascites (abdominal fluid)

•Atrial dilation leads to atrial arrhythmias

Question 3

Shunts

Answer 3

Question 4

ASD: Primum type

Answer 4

Question 5

VSD

Answer 5

•known VSD without overcirculation in nursery->

–As PVR falls, may see increasing shunting/overcirculation over 1st 1-2 weeks; requires close attention & followup

Question 6

Patent Ductus Arteriosus

Answer 6

Question 7

Pulmonary Stenosis

Answer 7

Question 8

Aortic Stenosis

Answer 8

Question 9

Adult Coarctation

Answer 9

Question 10

Fetal Coarcation

Answer 10

Question 11

Tetralogy of Fallot

Answer 11

•Tetralogy of Fallot

1. –Ventricular septal defect
2. –Pulmonary stenosis
3. –Overriding aorta
4. –Right ventricular hypertrophy

• All result from anterior malalignment of the outflow tract septum
• Mild vs severe PS: “pink” vs “blue” tets
• Infant with borderline sats starts crying, gets agitated

–Increased adrenergic tone -> increased RVOT obstruction -> more RTLS -> lower O2 sats -> more agitation -> loss of consciousness due to low sats

–“Tet spell”

–Treatment: calming, oxygen, morphine, B-blockers, peripheral vasoconstrictors (phenylephrine – alpha agonist)

•Squatting: unrepaired child will get SOB with activity, squats to recover

–Raising systemic vascular resistance

–Decreases RTLS, quicker recovery

Question 12

Cyanosis (3 types)

Answer 12

1. •Shunts with right-sided flow problems causes right-to-left shunting & cyanosis

–Eisenmenger syndrome: PVR > SVR

–Pulmonary valve stenosis with VSD: tetralogy of Fallot (“pink” vs “blue” Tets)

•Dynamic nature of shunting, maneuvers to manipulate shunting

2. “Reversed connections” – transposition of the great arteries

•Balloon septostomy urgently establishes some mixing

3. Single ventricles/common mixing lesions

•If pulmonary outflow is unobstructed, possible severe pulmonary overcirculation & systemic hypoperfusion

Question 13

Transposition of the Great Arteries (TGA)

Answer 13

Question 14

Severe obstruction to systemic outflow (CHD)

Answer 14

• •Severe obstruction to systemic outflow: coarctation/interrupted aortic arch
  
  • –Infantile shock reflecting possible ductal closure
  • –Prostaglandin E “buying time” for more controlled, elective repair
    
    • –Can think of it as returning the infant closer to the fetal circulation that allowed prenatal survival