12. Multiple Cardiac Anomalies- Exam 3 Flashcards
Cor Triatriatum=
heart with 3 apparent atria (tri-atrial heart)
-the left atrium (cor triatriatum sinistrum) or right atrium (cor triatriatum dextrum) is divided into 2 parts by a fold of tissue, a membrane, or a fibromuscular band
Cor Triatriatum: left atrium is known as
cor triatriatum sinistrum
–Misdiagnosed frequently as asthma, mitral stenosis or obstructed pulmonary venous return
Cor Triatriatum: right atrium is known as
cor triatriatum dextrum
–extremely rare
Cor Triatriatum- The membrane that separates the atrium into 2 parts varies significantly in size and shape.
•may be what 3 options
- a diaphragm
- funnel-shaped, bandlike, entirely intact (imperforate)
- contains 1 or more openings (fenestrations) ranging from small, restrictive-type to large and widely open
when/how does the Cor Triatriatum develop
-occurs when the common pulmonary vein fails to incorporate the pulmonary circulation into the left atrium.
•The result is a septum-like structure that divides the left atrium into 2 compartments
describe the development of the Cor triatriatum dextrum
- During embryogenesis, the original embryologic RA forms the trabeculated anterior portion of the RA
- Complete persistence of the right sinus valve of embryonic life results in separation of the smooth and trabeculated portions of the right atrium and constitutes cor triatriatum dextrum
he development of the Cor triatriatum dextrum forms a sheet that serves to do what?
serves to direct the oxygenated venous return from the IVC across the foramen ovale to the left side of the heart
If sheet formed from the Cor triatriatum dextrum is fenestrated and weblike, then it is referred to as the?
Chiari network
Cor Triatriatum mortality rate
may exceed 75% in untreated symptomatic infants.
•Severe obstruction = poor prognosis
The morbidity and mortality of cor triatriatum sinistrum is high in those who are symptomatic in infancy. Why?
due to the severely restrictive opening in the accessory membrane and the association with major cyanotic or acyanotic congenital heart lesions
Cor Triatriatum: surgery notes
- Performed soon after diagnosis
- Median sternotomy
- CPB + XC
- XC time is short
Cor Triatriatum: CPB considerations
- Procedure will be quick if the Pulmonary Veins are not involved
- Mild to “drift” cooling
- Circulatory arrest if a small child or Pulmonary veins involved
Cor Triatriatum: arterial and venous cannulation
Aortic Arterial cannulation
Bicaval cannulation: (open procedure)
Patent Ductus Arteriosis (PDA)=
the ductus arteriosus fails to close normally in an infant soon after birth.
•Leads to abnormal blood flow between the aorta and pulmonary artery (A-P shunt)
Patent Ductus Arteriosis (PDA): describe the flow
Allows antegrade flow from the RV to aorta prior to birth
Patent Ductus Arteriosis (PDA): difference in flow if it is open or closed
If closes: All flow out the aorta
If open: shunt Ao-PA (L->R due to ↓ PVR)
PDA size determines flow and Qp/QS
Patent Ductus Arteriosis (PDA): Extensive aortic runoff w/low aortic diastolic pressure will cause what?
organ hypoperfusion
Patent Ductus Arteriosis (PDA) is common in what demographics (4)
- affects girls more often than boys.
- common in premature infants and those with neonatal respiratory distress syndrome.
- seen in Down’s syndrome
- common in babies with congenital heart problems, such as hypoplastic left heart syndrome (HLHS), transposition of the great vessels (TGV/TGA), and pulmonary stenosis
Patent Ductus Arteriosis (PDA): If a large PDA is not corrected, then what can happen
-the pressures in the pulmonary arteries may become very high do to volume from the aorta.
-Shunt reversal can occur
•This situation is called “Eisenmenger’s syndrome”, a condition which may result from several similar abnormalites.
Eisenmenger’s syndrome=
Shunt reversal
Patent Ductus Arteriosis (PDA): goal of treatment? what the exception?
- The goal of treatment, if the rest of circulation is normal or close to normal, is to close the PDA.
- In the presence of certain other heart problems, such as HLHS the PDA may actually be lifesaving and medicine may be used to prevent it from closing
Patent Ductus Arteriosis (PDA): Sometimes, a PDA may close on its own. Premature babies have a high rate of closure within the first __ years of life. In full-term infants, a PDA rarely closes on its own after the first few ____
2 years
weeks
Patent Ductus Arteriosis (PDA): treatment via cath lab to close it
- A transcatheter device closure is a minimally invasive procedure that uses a thin, hollow tube.
- The doctor passes a small metal coil or other blocking device through the catheter to the site of the PDA. This blocks blood flow through the vessel.
Patent Ductus Arteriosis (PDA): treatment via OR to close it
- Surgery may be needed if the catheter procedure does not work or cannot be used.
- Surgery involves making a small cut between the ribs (thoracotomy) to tie off the PDA
Patent Ductus Arteriosis (PDA): treatment to keep it open
Prostaglandin E1 (PGE1),is known pharmaceutically as alprostadil
Patent Ductus Arteriosis (PDA): when is PGE1 given
prior to balloon atrial septostomy or surgery.
•therapy with PGE1 is continued until balloon atrial septostomy or cardiac surgery is done
Patent Ductus Arteriosis (PDA): how long does it take for PGE1 to take effect
the ductus will reopen within 30 minutes to 2 hours after starting PGE1
Patent Ductus Arteriosis (PDA): CPB considerations
Not a pump case when existing alone
▫Done in NICU/Peds ICU
Frequently seen with other anomalies in surgery
Patent Ductus Arteriosis (PDA): An _________ may have to be done if the balloon procedure fails. Done immediately with ____ or _____.
atrial septectomy
TAPVR, HLHS
Goals of Palliative Shunts:
- Increase pulmonary blood flow
- Decrease pulmonary artery blood flow
- Improve mixing
- Reduce ventricular work
Shunts to Increase Pulmonary Blood Flow=
Classic Blalock-Taussig shunt Modified Blalock-Taussig shunt Central Waterston Pott's Brock
Classic Blalock-Taussig shunt=
Subclavian to PA
Modified Blalock-Taussig shunt=
(gore-tex graft) Subclavian to PA
Central=
Ascending aorta to main PA (gore-tex graft)
Waterston=
Ascending aorta to RPA
Pott’s=
Descending aorta to LPA
Brock=
Pulmonary valvotomy, closed
Brock=
Pulmonary valvotomy, closed
Shunts to decrease pulmonary artery blood flow=
PA Banding
Shunts to Increase Mixing=
Blalock-Hanlon
Rashkind
Open Atrial Septectomy
Blalock-Hanlon=
blade septectomy – cath lab procedure
Rashkind=
balloon septostomy
Open Atrial Septectomy=
usually a concomitant procedure
Balloon Septostomy (Palliation)=
widening of a foramen ovale, (PFO), or ASD via cardiac cath (or bedside) using a balloon)
•This procedure allows a greater amount of oxygenated blood to enter the circulation (IMPROVES MIXING)
Shunts to Decrease Ventricular Work:
Bi-Directional Glenn Shunt
Anomalous Left Coronary Artery to Pulmonary Artery (ALCAPA)=
rare malformation in which the left coronary artery originates from the pulmonary artery
• leads to severe coronary hypoperfusion and left ventricular dysfunction when PVR falls in the postnatal period
ALCAPA: In fetal/early neonatal life, the left coronary artery (LCA) from the pulmonary artery (PA) is well tolerated because of what 3 things?
PAP = systemic pressure (leading to antegrade flow in both the anomalous LCA and the normal RCA)
•When PAP
ALCAPA: when PAP = systemic pressure- this leads to what
leading to antegrade flow in both the anomalous LCA and the normal RCA
ALCAPA: when PAP
flow in the LCA decreases and then reverses, which leads to myocardial ischemia and infarction
ALCAPA: As long as PVR is high, coronary perfusion is maintained even if what happens?
the anomalous artery carries desaturated blood coming from the pulmonary artery. When pulmonary artery pressure falls, perfusion of the left coronary artery becomes inadequate
ALCAPA: If the LCA is dominant and if intercoronary collaterals are inadequate–what happens?
severe left ventricular dysfunction with ischemic mitral regurgitation develops
–the prognosis is poor
ALCAPA: If the RCA is dominant and if collaterals develop efficiently–what happens?
normal LCA perfusion may be maintained while left-to-right shunt from the right coronary artery to the left coronary artery and the pulmonary artery progressively increases
goal of ALCAPA surgery
The aim of surgery is to restore a two-coronary-artery circulation system
- 2 techniques are used
1. Coronary Reimplantation
2. Takeuchi procedure
Takeuchi procedure=
A transpulmonary baffle between the coronary ostium in the PA and the Ao is created.
•Baffles (tunnels) blood across Aorta–>PA
ALCAPA: arterial+venous cannulas
Aortic Arterial cannulation
Bicaval cannulation: (open procedure)
ALCAPA: LV venting
a left ventricular vent is inserted through the superior right pulmonary vein (RSPV) and both pulmonary arteries are snared to avoid runoff of coronary perfusion into the pulmonary circulation
ALCAPA: cardioplegia
Aortic root + ostial:
•The first cardioplegic administration is performed in the aortic root (and thus right coronary artery) and it is completed by direct administration into the anomalous LCA (ostial)
•Both RCA and LCA ostial are given for maintenance doses
ALCAPA: temperatures
Hypothermia: Normothermic cardiopulmonary bypass
•although moderate hypothermia may be necessary to allow low flow bypass if needed
ALCAPA: It is very useful to create a small ______ as a way to unload the failing left ventricle during the early postoperative period
atrial septal defect
ALCAPA: terminating bypass
After aortic unclamping, a LA line is inserted and weaning from CPB is prepared.
•However, CPB must be prolonged for a while until LA pressure (which is initially high) reaches an acceptably low level, allowing weaning with a moderate inotropic support
ALCAPA: when terminating bypass, if the LA pressure does not drop to an acceptable level, what do you do?
a left heart VAD or ECMO must be done to allow cardiac assistance for a few days until left ventricular function recovers enough to allow weaning in good hemodynamic conditions.
Vascular Rings Double Aortic Arch=
Trachea and esophagus are encircled by vascular structures
Vascular Rings Double Aortic Arch: Right arch (posterior)=
Right common carotid
Right subclavian
Vascular Rings Double Aortic Arch: Left aortic arch (anterior)=
Left common carotid
Left subclavian
Vascular Rings Double Aortic Arch: Surgical division of the vascular ring is indicated in what patients
in any patient with symptoms of airway or esophageal compression and in patients undergoing surgery for repair of associated cardiovascular or thoracic anomalies
Vascular Rings Double Aortic Arch: Surgical division of the vascular ring is indicated in what patients
in any patient with symptoms of airway or esophageal compression and in patients undergoing surgery for repair of associated cardiovascular or thoracic anomalies
Vascular Rings Double Aortic Arch: surgical correction steps (3)
- The chest is entered between the fourth and fifth rib (thoracotomy) (as in the operation for PDA or aortic coarctation)
- Upon dissecting the arches off the trachea and esophagus, the arches can be divided. After division the two aortic ends are oversewn with 2 running layers of non-absorbable sutures
- Additional relief can be obtained by stitching the lateral wall of the aorta to the adjacent rib to pull it away from the esophagus
Vascular Rings Double Aortic Arch: CPB considerations
Incision: left lateral thoracotomy
CPB: Off pump
Interrupted Aortic Arch (IAA)=
absence or discontinuation of a portion of the aortic arch
-3 types
Interrupted Aortic Arch (IAA): thought to be a result of faulty development of the aortic arch system during what week of fetal development?
fifth to seventh week of fetal development.
–This defect is almost always associated with a large VSD.
Interrupted Aortic Arch (IAA)- Type A=
interrupted left aortic arch: the arch interruption occurs distal to the origin of the left subclavian artery
Interrupted Aortic Arch (IAA)- Type B=
interrupted left aortic arch, the interruption occurs distal to the origin of the left common carotid artery.
Interrupted Aortic Arch (IAA)- Type C=
interrupted left aortic arch, the interruption occurs proximal to the origin of the left common carotid artery
An interrupted aortic arch can coexist with any _____
ventriculoarterial alignment
Interrupted Aortic Arch (IAA): During fetal development: -left ventricular output supplies the?
-right ventricular output supplies the?
left= arterial circulation proximal to the interruption right= arterial circulation distal to the interruption via the left ductus arteriosus
Interrupted Aortic Arch (IAA): Postnatally, this arrangement continues, with the addition of the
pulmonary blood flow to the load of the left ventricle
Approximately one half of patients with interrupted aortic arch have a hemizygous deletion of a ____ region of chromosome band ____, the most common deletion syndrome in humans
- 5-3 Mb
22q11. 2
Interrupted Aortic Arch (IAA): surgical correction: attention is increasingly focused on the preoperative identification and surgical management of what?
the aortic valve and subaortic stenosis found in approximately one half of cases.
Interrupted Aortic Arch (IAA): arterial+venous cannula
•Arterial: uses 2 aortic cannula: The arterial line is “Y’d” to allow 2 identical cannula (i.e. 2 - 8fr.) to be used to ensure an even split of flow
▫Circulation is divided into upper and lower body
•Venous: Single Venous
Interrupted Aortic Arch (IAA): cardioplegia
The first cardioplegic administration is performed in the aortic root.
•Subsequent doses may be ostial
Interrupted Aortic Arch (IAA): temperatures
Hypothermia: DHCA to allow arch and head vessel reconstruction (rarely antegrade cerebral and retrograde cerebral perfusion since head vessels rarely have to be cut off)
Interrupted Aortic Arch (IAA): temperatures
Hypothermia: DHCA to allow arch and head vessel reconstruction (rarely antegrade cerebral and retrograde cerebral perfusion since head vessels rarely have to be cut off)
Aortic Coarctation=
due to an abnormality in development of the embryologic left fourth and sixth aortic arches
•Congenital narrowing with varying degrees of hypoplasia can exist
Aortic Coarctation: treatment
Balloon Aortoplasty
Aortic Coarctation: Four predominant repairs
- Left subclavian patch angioplasty
- Resection: End-to-end anastamosis
- Subclavian translocation
- Patch angioplasty
Aortic Coarctation: CPB considerations
- Incision: posterior left lateral thoracotomy
- Aorta is clamped, cut and re-sewn off CPB
- CPB: Off pump standby or LHB
- In rare cases of severe coarctation left heart bypass can be utilized from LA to descending aorta
