The initial primitive heart tube is the _______________.
Primitive left ventricle
The ___________ forms from the proepicardial organ.
Epicardium
_______________ is the first step in chamber formation and partitioning.
Cardiac looping
The developing heart normally loops to the ______.
Right
Dextrocardia
Right-sided mirror image heart - associated w/ situs inversus
Defect in cilia - problems rotating and folding
What drives looping?
Addition of cardiac precursors from the secondary heart field
During looping the atria and ventricular chambers ________ due to ___________.
Expand
Ballooning
What is the result of looping?
Proper anatomical relationships between segments and septa
Heart begins to beat at _________.
21-22 days
The precursor tissue of the heart develops from the _______________.
Splanchnic Mesoderm
The smooth part of the left atrium are derived from ________________. while the appendage is derived from the __________.
2. Primordial atrium
The common AV opening expands/shifts due to ______________.
Myocardialization of the inner curvature
Atrial septum operates as a ________ allowing unidirectional blood flow form _______ to ______.
What is a fixed S2 split indicative of?
ASD - 90% occur w/ secundum at fossa ovalis
What is the most common congenital heart anomaly?
VSD - membranous at septum (90%)
What does a harsh, continuous “machinery like murmur” indicate?
PDA
What congenital defect is commonly seen in Down syndrome?
AVSD
What is the most common form of cyanotic congenital HD?
Tetralogy of Fallot
A boot shaped heart indicates what congenital defect?
Tetralogy of Fallot - DiGeorge and Trisomy 21
What is tetralogy of Fallot?
Who is TGA more common in?
Male children and with diabetic mothers
How does the heart remodel in TGA?
Stable w/ VSD (35%)
RV Hypertrophy, pulmonary HTN
Ovall/egg-shaped cardiac silhouette
Mild cardiomegaly
What two congenital heart defects are associated with DiGeorge Syndrome?
Tetralogy of Fallot and Truncus arteriosus
Tricuspid atresia needs what two defects to coexist?
2. VSD