Ventricular Hypoplasia Flashcards
HLHS, HRHS/tricuspid atresia
What is Hypoplastic Left Heart syndrome and what are some of the characteristics?
HLHS is a cyanotic abnormality with a severally underdeveloped lefts sided structures.
-Hypoplastic LV
-underdeveloped/atretic MV & AV (MS/AS)
-atretic AV with hypoplastic AAO
-RVE and hypertrophic RV
-ASD for left heart flow
atretic meaning blocked or not letting flow through
In HLHS systemic circulation is ____dependent?
Ductal dependent
PDA flow R-L
Since the left side is severally underdeveloped in the setting of HLHS how does the neonate receive majority of the systemic blood?
Systemic circulation is dependent on the PDA.
-PDA shunt will be RIGHT to LEFT
**hence why this is a cyanotic congenital abnormality
HLHS AAO interegation should show
AAO flow is retrograde for coronary circulation
HLHS PDA Interogation
PDA size
PDA flow R-L
PA dilation
*prostaglandin to keep PDA open
What congenital findings associated with HLHS?
CoA
Interrupted Aortic Arch (IAA)
What is the most common congenital heart defects that can cause death in neonates?
Hypoplastic left heart syndrome (HLHS)
HLHS is more prevalent in?
male or female
Males
Surgical procedure name?
How many stages is the procedure?
Hypoplastic Left Heart Syndrome, HLHS
Corrective surgery is performed in 3 stages, the 3 stage surgeries are known as the Norwood procedure
What is the immediate goal when trying to surgically correct a HLHS?
Converting the RV from a pulmonary circuit to systemic circulation
-and separating the pulmonary and systemic circulations
Hypoplastic Left Heart Syndrome, HLHS
When is the 1st stage of the Norwood usually performed?
Typically, a palliative stage, performed within first few days of life.
Hypoplastic Left Heart Syndrome, HLHS
Norwood stage 1 procedure involves
-palliative options
-main surgical step
constructing a neo-aorta by cutting and suturing the main PA from its branches and attaching/combining it to the hypoplastic AO base and PV
- homograft or autograft patch is used to enlarge AO
-PDA closed
Two palliative procedures in this stage to establish systemic-to-pulmonary connection are:
- Blalock Taussig shunt (BT shunt) between innomonate /BA/RSA to RPA
- Sano shunt, synthetic conduit is placed between the RV and the PA
Hypoplastic Left Heart Syndrome, HLHS
Norwood stage 2 procedure involves
- two other names for this procedure
- main surgical step
also known as Glenn procedure or Hemi Fontan
-Blalock-Taussig (BT) shunt is removed
-SVC is detached from the RA and attached to the RPA establishing systemic venous-to-pulmonary circulation.
** intracardiac mixing will still occur from the IVC
Hypoplastic Left Heart Syndrome, HLHS
When is the Glenn or Hemi Fontan procedure typically performed?
Usually, 4-6 months as a bridge to the third stage of the Norwood.
Hypoplastic Left Heart Syndrome, HLHS
Norwood stage 3 procedure involves
- another name for this step is
- what surgery step is done during this stage
Also known as the Fontan stage
-IVC is attached to the RPA via a tunnel-like patch through the RA or a conduit outside the RA to the RPA
-a fenestration (hole) between tunnel or conduit may be made to relieve high pressures
Hypoplastic Left Heart Syndrome, HLHS
When is the Fontan procedure typically performed?
2 to 3 years of life
hypoplastic right heart syndrome, HRHS definition
All right heart structures are small and dysplastic or atretic
simular to HLHS only affects the right side
HRHS is usually associated with
tricuspid atresia
(may also have pulmonary atresia)
dense, fibrous membrane or plate covering TV opening, no antegrade flow
in HRHS what is necessary for survival
ASD
right to left shunt
HRHS is highly associated with what two congenital defects
Don’t think of shunts
CoA
TGA
HRHS requires what surgical intervention for survival?
Single ventricle/Fontan Repair
Two dimensional findings on echo in HRHS/tricuspid atresia
membrane obliterating the TV orifice (no flow antegrade flow)
small RV
small PA annulus (dysplasia/atretic)
PDA
LVE
LV function may be low due to vol overload
tricuspid atresia definition
cyanotic abnormality characterized by complete failure of the TV to form (RA and RV not connected)
-AO and PA can be normal relation or transposed
In tricuspid atresia the pulmonary circulation is dependant on?
PDA or VSD
VSD is not always present
Degree of tricuspid atresia depends on if there is a
VSD present and the amount of obstruction to the PV
patients with large VSD’s and no pulmonary obstructions will often exhibt incrase pulmonary circulation and experience minimal cyanosis
Tricuspid Atresia is associated with
D-TGA
L-TGA
PLSVC
CoA
Right AO arch
Surgical repair of HRHS/tricuspid atresia involves
- Palliative BT shunt to increase pulmonary flow at 4-6wks,
-if there is a large VSD with excessive pulmonary flow, pulmonary banding may be required instead of a BT shunt. - A two stage fontan procedure
* Glenn (hemi Fontan):
-performed at 4-6months, BT shunt takedown, main PA excised,
-SVC is excised at rt. atrial level and anastomosed to the RPA (making a systemic venous to PA connection)
-intracardiac mixing at atrial level still occurs
* Fontan procedure:
-performed at 2-3 years of age
-complete seperation of systemic and pulmonary circulation
-IVC connected to RPA, either extracardiac or by tunnel like patch through RA
-ASD closed
-A small fenestration hole between lateral tunnel/conduit and the RA to relieve high pressures
lateral tunnel through RA is called (Lateral Tunnel Fontan Procedure)
