Abnormalities of Ventricular Outflow Flashcards
AS, Sub/Supra AS, CoA, interrupted aortic arch
PDA usually closes within hours or days or a newborn who has achieved ___ weeks gestation
40 weeks
What is the typical origin to find a CoA?
Just distal to the left subclavian artery and just opposite to the PDA, where the natural occurring aortic shelf (aortic isthmus) is located.
Can occur at any level o the AO including the abdominal AO
What are the 3 types of CoA based upon the relationship of the PDA?
Preductal
Juxtaductal
Postductal
What is considered a significant pressure gradient across the Aortic Shelf and is indictive of CoA?
Any pressure gradient greater than 16mmHg is abnormal.
CW Doppler may show “shelfing” representing normal AO flow and higher velocity CoA flow with diastolic runoff
How does CoA affect the blood pressure?
CCI
Elevated upper extremity BP with lower BP in the lower extremities
upper pressures can be significantly higher by 10mmHg or more.
What is a sign of CoA when dopplering the abdominal AO?
When abdominal AO is non-pulsatile and blunted, always consider CoA.
A: Normal individual. B: Severe aortic insufficiency. C: Severe coarctation. D: Individual with tricuspid atresia and failed systemic venous to pulmonary artery connection (Fontan operation) demonstrating a low cardiac output and increased peripheral vasoconstriction.
What is often associated with CoA?
Bicuspid AV is present 50% of the time.
VSD
PDA
Congenital cardiac anomalies and shunts associated with CoA may include?
-PDA, ASD, VSD
-AS or LVOT obstruction
-Cor triatriatum
-D-TGA
-DORV
Can CoA develop in a newborn who recently underwent PDA ligation?
Yes, one should always interrogate the AO post PDA ligation on every exam.
What is a clinical sign on chest x-ray in the presence of CoA
Figure “3” sign and rib notching
CoA EKG often shows
LVH
Name the 4 surgical repairs for CoA Repair and the pros and cons of each.
- Balloon angioplasty done in the cath lab
- End-to-end anastomosis: 2 ends of the AO are sutured together, this is the preferred method because it preserves LSA.
- Synthetic Dacron graft/patch: Coarcted portion is resected and replaced with a patch, preserves LSA but at risk for AO aneurysm later on
- LSA Patch: LSA is excised from AO and used to repair coarct. There is less chance of rejection, however, loss of the LSA reduces the blood supply to the left arm.
Congenital AS is more prevalent in males or females?
Males
Two surgical repairs used to correct AS
- Ross procedure: switch PV to AV position, insert a RV-PA conduit
- konno procedure: Involves an incision from the aortic root down through the ventricular septum to widen the LVOT.
- Can have a combinationof the two
Can also do a balloon valvuloplast
What syndrome is highly associated with supravalvular AS
Williams syndrome
Supravalvular AS will appear hourglass shape in the AAO in PLAX
Bicuspid AV is highly associated with
CoA
What is the leading cause of sudden unexplained death in young athletes?
Hypertrophic obstructive cardiomyopathy, (HOCM, HCM)
-subaortic stenosis
Congenital cardiac defect associated with subaortic stenosis are?
IAA
CoA
VSD’s
Definition of AP window and direction of shunt
rare supravalvular defect which there is direct communication between AAO and MPA superior to semilunar valves
-shunt is usually L-R
AP window can cause what affect on the heart
enlarged right side structures and PHTN due to volume overload
AP window Surgical repair usually involves?
Closing the AP window ASAP with a synthetic patch or small piece of pericardium.
sooner to reduce permenant damage to the lungs
Are there usually other cardiac defects associated with a AP window?
Yes, 50% of the time
- IAA, type A
- CoA
- TET
- Anomalous coronaries
- AO atresia
- D-TGA
- Double AO arch
Definition of interrupted aortic arch
Complete separation of the arch between the AAO and the DAO.
What are the three types of IAA
-percentages
Type A (30-40%): distal to the LSA
Type B (55-60%): occurs between the LCC and LSA
Type C (rare; less than 5%): occurs distal to the brachiocephalic artery and proximal to LCC
Clinical sign of IAA
Cyanosis of the lower extremities
tachypnea
CHF
shock
With IAA how does the lower extremity receive blood flow?
continuation of the main PA through the ductus arteriosus
Nearly ALL IAA will have what type of shunt?
-direction
Don’t think about the PDA shunt
VSD
L-R flow
helps increase O2 flow in the PA for the DAO segment and lower extremities
What type of anastomosis is used to surgically repair IAA?
end-to-end
What type of murmur is PPS
Systolic murmur that radiates to the back
When trying to figure the pressure gradients in PPS other than the PA pressures themselves what other way can you measure the gradient?
TR Jet
RVSP
In PPS it’s important to measure the branches for ___ placement?
Stent/balloon angioplasty
True or false, Pulmonary branch stenosis usually occurs as a result of PHTN?
True
vasoconstrictive response to reduce flow to the lungs due to elevated pressures in the lungs, resolve over time if no other major complications
What is considered abnormal pressure gradient across the Pulmonary artery?
gradients greater than 16mmHg
normal pressures are a third of systemic pressures
Pulmonary artery banding purpose is to
used to alleviate severe pulmonary over circulation in neonates
Tightened till pressures distal to the band are within normal range
Definition of double chamber RV
septated RV into a proximal and distal portion by a hypertrophied muscle bundles
What is highly associated with double RV
VSD
subaortic stenosis
Best view to appreciate the double RV is
Subcostal coronal view with an anterior tilt to the RVOT
subcostal long axis
Definition of pulmonary atresia
cyanotic defect lacking the normal opening at the level of the PV, no antegrade flow
What are the two types of pulmonary atresia
membranous: thin may be able to perforate
fibromuscular: thick muscular obstruction, requires surgery
In pulmonary atresia pulmonary flow is ____ dependent?
Ductal dependent
prostaglandins administered to keep PDA open
What should be closely evaluated within the RV muscle when pulmonary atresia is present
myocardial sinusoids especially in cases with intact IVS, decrease color scale to rule out
coronary artery sinusoids
could be resposible for cardiac ischemia and death following repair if not identified
Severity of pulmonary atresia with intact ventricular septum (PA-IVS) depends on?
Degree of RV hypoplasia
tricuspid valve stenosis
if coronary artery sinusoids are present
What can be done to increase pulmonary flow in the setting of pulmonary atresia?
atrial septostomy
Pulmonary atresia in the setting of a large VSD is commonly considered
to be a severe form of Tetralogy of Fallot
In general, pulmonary atresia surgery
can vary drastically depend on if the septum is intact or not
can resemble Tet repair if VSD present
or a single ventricle repair if RV hypoplastic no VSD
palliative BT shunt, then transannular patch to open the RVOT and new PV
Left aortic arch lies to the ___ of the trachea
Left
The branches are part of what segment of the AO arch?
Transverse AO
Right aortic arch is a ___ image of the left
Mirror image (turn probe slightly to the right arm)
Branches in this order:
RSA
RCCA
Left side BA
Right aortic arch is highly associated with
TOF
In embryology, Two primitive aortic tubes encircle esophagus and trachea forming a vascular ring. Which tube should dissipate to leave a normal aortic arch?
Right arch should dissipate leaving the BA, and RCCA behind. And the left arch will form as normal making the LCCA and LSA
Double aortic arch occurs when
right aortic arch fails to dissipate during development in the vascular ring continues to circle the trachea and esophagus.
What happens when the left arch dissipates leaving the right arch
The right arch becomes dominant and is a mirror image of a left aortic arch
Sometimes the origin of the branches can be affected
In the presence of a double aortic arch, what should be determined?
Which arch is dominant by measuring the flow across both arches
Determine the origin of the branches
