Case 18 Flashcards
What are key findings from history in a child with a VSD and CHF?
Poor feeding, respiratory distress, diaphoresis
What are key physical exam findings from a child with VSD?
Tachypnea, Murmur, hepatomegaly
What is on the differential diagnosis for VSD/CHF?
Bronchiolitis, Pneumonia, GERD, Metabolic disorder
What is seen in a CXR of VSD?
Cardiomegaly, increased pulmonary vascular markings, and pulmonary edema (hallmark findings of a large left-to-right shunt due to congenital heart defect)
What is seen on electrocardiogram of VSD?
Prominent biventricular forces (high voltage QRS complexes in leads V1 and V2), suggesting both LV volume overload and RV pressure overload
What is seen on an echocardiogram of VSD?
2D ECHO demonstrates a large perimembranous ventricular septal defect in the sub-aortic region
Definition of a VSD?
Any persistent communication between the ventricles occurring in isolation or as part of a more complex defect.
What is the anatomy associated with VSD?
Defect of variable size located along embryologic lines of fusion in the ventricular septum.
What is the physiology associated with VSD?
- Left-to-right shunting of blood during ventricular systole causes increased pulmonary blood flow, increased pulmonary venous return, and resultant left ventricular volume overload.
- Magnitude of the shunt depends on size of defect and difference between systemic and pulmonary vascular resistance.
- Newborns have elevated pulmonary vascular resistance. Because the systemic and pulmonary vascular resistances are nearly equal, there is no reason for blood to shunt through the VSD. The murmur of a VSD will appear when the PVR drops, usually at a few days to weeks of age.
What is the presentation of VSD?
- Murmur and clinical signs usually not present in the newborn nursery but are noted from several days to weeks of age.
- Age of presentation and symptoms related to magnitude of left to right shunt.
- Large defects often present with CHF as pulmonary resistance falls in the first weeks of life.
- Small defects usually cause no symptoms
- VSDs tend to diminish in size with time. There is spontaneous closure of approximately 75 percent of small defects and between 25-50 percent of all defects.
- Hyperactive precordium frequently with a thrill at the lower left sternal border.
Etiology of CHF in infancy:
- Heart defects that present with a murmur and signs of CHF in infancy include VSD, severe aortic stenosis or coarctation of the aorta, and a large patent ductus arteriosus (PDA).
- Many other congenital heart defects, such as ASD, do not cause CHF. Most cyanotic heart defects, like tetralogy of Fallot, cause decreased pulmonary blood flow and therefore doe not cause CHF.
How do CHF present in infancy?
- Infants with heart disease are generally otherwise healthy.
- Typically presents with predominantly respiratory symptoms (tachypnea) and feeding difficulties
- The history will often reveal that infant is feeding for longer periods of time than norma, and that feedings are terminated due to respiratory distress.
- Infants frequently become diaphoretic with feedings. Diaphoresis suggests adrenergic activation and is a major sign of CHF in infants.
- Ultimately, due to poor feeding and increased caloric expenditure, poor weight gain ensues (Failure to thrive)
- Hepatomegaly is a reliable finding in infants with heart failure:
- -Decreased renal blood flow via activation of renin-angiotensin system leads to fluid retention, systemic venous congestion and hepatomegaly
How often do breastfeeding and bottle feeding infants usually nurse?
- Young, breastfeeding infants usually nurse for 20-30 min, as often as every 1-2 hours.
- Bottle-fed infants often take more per feed and feed a little less often
How would a problem with maternal breast milk production present?
It would be more likely to present with the infant trying to feed more frequently and continually acting hungry.
Weight loss in a newborn:
- Newborns typically lose between 5-10 percent of their birth weight in the first few days after birth. Most will be back to birth weight by 10-14 days.
- Failure to gain weight adequately in infancy or childhood is referred to as “failure to thrive”
What is a strong indicator of coarctation of the aorta?
A discrepancy in the strength of the brachial and femoral pulses.
What is a simple way to grade murmur intensity?
Grade I - faint and easily missed.
Grade II - obvious
Grade III - loud
Grade IV - Associated with a thrill
What grade of murmur is likely to be pathologic?
Any grade III or IV murmur is likely to be pathologic, and probably should be evaluated by a cardiologist.