Topic 9: ASD / VSD Flashcards
1 year
systolic/diastolic
98-104
55-60
2 year
systolic/diastolic
101-107
59-64
5 year
systolic/diastolic
104-114
69-72
> 36 gestation full term
systolic/diastolic
68/43
ASDs - occurs what two places
Most commonly occur as defects in the septum primum within the fossa ovalis (secundum ASD)
Defect can involve the septum secundum near SVC (sinus venosus defects-less common)
Will cause pressure mediated shunting
L->R *compliant right heart
R->L
ASDs most commonly occur where?
Most commonly occur as defects in the septum primum within the fossa ovalis (secundum ASD)
Compliant right heart with an ASD will cause what kind of shunting?
L –> R
What ratio do you intervene with ASDs (Qp:Qs ratio)
The general rule is shunts that DO NOT cause right heart size (Qp:Qs
Most common ASD called what?
Ostium Secundum -(Mid atrial, Most common)
how is Ostium Secundum formed?
formed by failed growth of the septum secundum or
rapid reabsorption of the septum primum
What is the only type of ASD that allows for percutaneous closure?
Ostium Secundum
ASDs - occurs what two places
Most commonly occur as defects in the septum primum within the fossa ovalis (secundum ASD)
Defect can involve the septum secundum near SVC (sinus venosus defects-less common)
Will cause pressure mediated shunting
L->R *compliant right heart
R->L
ASDs most commonly occur where?
Most commonly occur as defects in the septum primum within the fossa ovalis (secundum ASD)
Compliant right heart with an ASD will cause what kind of shunting?
L –> R
how is Ostium Secundum formed?
formed by failed growth of the septum secundum or
rapid reabsorption of the septum primum
What is the only type of ASD that allows for percutaneous closure?
Ostium Secundum
PFO
A patent foramen ovale (PFO) is a small channel that has little hemodynamic consequence; it is a remnant of the fetal foramen ovale.
In some cases the PFO can be larger and require treatment
Channel from birth
Normally closes due to pressure changes very early in life
“flap valve”
How does PFO close?
The initial inflation of the lungs causes
changes:
Decreases PVR results in increased blood flow from PA.
That increased amount of blood flows from the RA to the RV and into the PA’s and less blood flows through the foramen ovale to the left atrium
In addition, more blood returns from the lungs which increases the pressure in the LA.
The increased LA pressure and decreased RA pressure (due to pulmonary resistance) forces blood against the septum primum causing the foramen ovale to close.
This action functionally completes the
separation of the heart into two pumps
Ostium Primum ASD - located where?
Located low in the septum
Considered a type of AV Septal Defect (AVSD)
Could have RA saturations lower than RV without a VSD
Sinus Venosis ASD - located where?
located high in the septum where the vena cava intersects with the right atrium, frequently associated with partial anomalous venous return (PAPVR)
May be inferior and/or superior
May have PAPVR
Embryonic/fetal circulation is ____ to the neonatal circulation
different
Embryonic septation forms
separate chambers
One septal “defect” occurs in us all - -which ?
the foramen ovale (between the 2 atria) which in general closes in the neonate over time
Cardiac Septation when ?
Occurs at Day 27 Lasts 10 days The formation of the cardiac septa occur simultaneously During this time, no major changes in external appearance
Atrial Septation - when? how long?
At day 27-28, the paired atria fuse together to form a common atrium.
Atrial septation occurs simultaneously and in
cooperation with ventricular septation
Atrial septation also lasts approximately 10days