Multiple Cardiac Anomalies Flashcards
Cor Triatriatum
- cor triatriatum is a heart with 3 apparent atria (tri-atrial heart)
- congenital anomaly in which 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 The membrane that separates the atrium into 2 parts varies significantly
significantly in size and shape.
Cor Triatriatum may be
▫ a diaphragm
▫ funnel-shaped, bandlike, entirely intact (imperforate)
▫ contains 1 or more openings (fenestrations) ranging from small, restrictive-type to large and widely open.
Cor Triatriatum dextrum
Right Atrial • extremely rare
Cor Triatriatum sinistrum
- Left Atrial
* Misdiagnosed frequently as asthma, mitral stenosis or obstructed pulmonary venous return
Pathophysiolology
• Cor -Triatriatum sinistrum
Current theory holds that cor triatriatum sinistrum 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.
cor triatriatum Cases have been reported in which
1 or 2 pulmonary veins drain into the proximal (accessory) chamber and the others drain directly into the true LA.
• Others believe that the membrane dividing the left atrium is an abnormal growth of the septum primum.
Cor triatriatum dextrum patho
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. This forms a sheet that serves to direct the oxygenated venous return from the IVC across the foramen ovale to the left side of the heart.
Chiari network.
the foramen ovale to the left side of the heart. If this membrane is fenestrated and weblike,
he morbidity and mortality of cor triatriatum sinistrum
is high in those who are symptomatic in infancy.
▫ -this is due to the severely restrictive opening in the accessory membrane and the association with major cyanotic or acyanotic congenital heart lesions.
sinustrum Mortality may exceed
75% in untreated symptomatic infants.
• Severe obstruction = poor prognosis
Surgery Notes
• Performed soon after diagnosis • Median sternotomy • CPB + XC • XC time is short
CPB Considerations: Cannulation
As with ASD’s/VSD’s: • Aortic Arterial cannulation
• Bicaval cannulation: (open procedure) • 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
Patent ductus arteriosus (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),
PDA Flow
• Allows antegrade flow from the RV to aorta prior to birth
• If closes: All flow out the aorta • If open: shunt Ao-PA (L->R due to ↓ PVR)
PDA size determines flow and Qp/QS
Extensive aortic runoff w/low aortic diastolic pressure will cause organ hypoperfusion
Patent Ductus Arteriosis
• -affects
girls more often than boys.
PDA COMMON ON
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
If a large PDA is not corrected, then the pressures in the pulmonary arteries may become very high do to volume from the aorta.
If a large PDA is not corrected, then the pressures in the pulmonary arteries may become very high do to volume from the aorta.
• Shunt reversal can occur in PDA and is called
Eisenmenger’s syndrome”, a condition which may result from several similar abnormalites.
closing the PDA
• 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.
Sometimes, a PDA may close on
its own. Premature babies have a high rate of closure within the first 2 years of life. In full-term infants, a PDA rarely closes on its own after the first few weeks.
closing the PDA
• CATH:
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. Such endovascular coils have been used successfully as an alternative to surgery.
closing the PDA: OR
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.
Surgical Correction keeping the duct open
Exogenous prostaglandins can be used to artificially extend the patency of the ductus in neonates where bypassing the defective vessel or continued mixing of oxygenated and unoxygenated blood is needed to provide adequate systemic circulation.
• Prostaglandin E1 (PGE1),is known pharmaceutically as alprostadil
Surgical Correction keeping the duct open
• PGE1 is routinely used
In infants with ductus- dependent cardiac lesions to improve circulation prior to balloon atrial septostomy or surgery.
therapy with PGE1 IS CONTINUED
is continued until balloon atrial septostomy or cardiac surgery is done.
In most infants, the ductus will reopen
within 30 minutes to 2 hours after starting PGE1
CPB CONSIDERATIONS PDA
Not a pump case when existing alone ▫ Done in NICU/Peds ICU
• Frequently seen with other anomalies in surgery • An atrial septectomy may have to be done if the
balloon procedure fails • Done immediately with 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
Subclavian to PA
Shunts to Increase Pulmonary Blood Flow:Modified Blalock-Taussig shunt
(gore-tex graft)
• • • •
Subclavian to PA
Shunts to Increase Pulmonary Blood Flow:Central
Ascending aorta to main PA (gore tex graft)
Shunts to Increase Pulmonary Blood Flow:Waterston
Ascending aorta to RPA
Shunts to Increase Pulmonary Blood Flow:POTTS
Descending aorta to LPA
Shunts to Increase Pulmonary Blood Flow:Brock
Pulmonary valvotomy, closed
Shunts to decrease pulmonary artery blood flow :
• PA Banding
Shunts to Increase Mixing: blalock hanlon
blade septectomy – cath lab procedure
Shunts to Increase Mixing: rashkind
balloon septostomy
Shunts to Increase Mixing: open atrial septectomy
usually a concomitant procedure
Balloon Septostomy (Palliation)
Balloon septostomy is the 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
ALCAPA
Anomalous left coronary artery from the pulmonary artery (ALCAPA) rare malformation in which the left coronary artery originates from the pulmonary artery
ALCAPA leads to
evere coronary hypoperfusion and left ventricular dysfunction when PVR falls in the postnatal period.
In fetal/early neonatal life, the left coronary artery (LCA) from the pulmonary artery (PA) is well tolerated because:
PAP = systemic pressure (leading to antegrade flow in both the anomalous LCA and the normal RCA)
ALCAPA When PAP < Systemic pressure
(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 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
nd if intercoronary collaterals are inadequate, severe left ventricular dysfunction with ischemic mitral regurgitation develops; the prognosis is poor
ALCAPA if the RCA is dominant
and if collaterals develop efficiently, 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;
Surgical correction performed on making a diagnosis of ALCAPA syndrome
diagnosis of ALCAPA syndrome is considered to be the standard treatment.
ALCAPA The aim of surgery is to
restore a two-coronary- artery circulation system
ALCAPA Technique I:
Coronary Reimplantation
ALCAPA technique 2:
Takeuchi procedure. A transpulmonary baffle between the coronary ostium in the PA and the Ao is created.
• Baffles (tunnels) blood across AortaPA
ALCAPA cpb considerations cannulation hypothermia lv vent
Aortic Arterial cannulation • Bicaval cannulation: (open procedure)
• Hypothermia: Normothermic cardiopulmonary bypass • although moderate hypothermia may be necessary to allow
low flow bypass if needed
• LV Vent: 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 CPB Considerations
• 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 COMING OFF BYPASS
It is very useful to create a small atrial septal defect as a way to unload the failing left ventricle during the early postoperative period.
• After aortic unclamping, a LA line is inserted and weaning from cardiopulmonary bypass is prepared.
• However, cardiopulmonary bypass must be prolonged for a while until left atrial pressure (which is initially high) reaches an acceptably low level, allowing weaning with a moderate inotropic support.
• If this is not the case, 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 ArchLeft aortic arch (anterior)
Left common carotid ▫ Left subclavian
Vascular Rings Double Aortic Arch surgical correction
Surgical division of the vascular ring is indicated in any patient with symptoms of airway or esophageal compression and in patients undergoing surgery for repair of associated cardiovascular or thoracic anomalies
vascular ring Surgical Correction
• The chest is entered
between the fourth and fifth rib (thoracotomy) (as in the operation for PDA or aortic
coarctation)
vascular ring Surgical Correction. 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
vascular ring Surgical Correction. 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 ring cpb considerations
Incision: left lateral thoracotomy • CPB: Off pump
Interrupted Aortic Arch (IAA) is
the absence or discontinuation of a portion of the aortic arch.
Interrupted Aortic Arch is thought to be
a result of faulty development of the aortic arch system during the fifth to seventh week of fetal development. This defect is almost always associated with a large VSD.
Interrupted Aortic Arch (IAA)
• 3 types: based on
the site of aortic interruption:
•
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.
interrupted aortic arch can coexist
with any ventriculoarterial alignment
Interrupted Aortic Arch (IAA. During fetal development, left ventricular output supplies the
arterial circulation proximal to the interruption whereas right ventricular output supplies 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 1.5-3 Mb region of chromosome band 22q11.2, the most common deletion syndrome in humans
Surgical Correction- IAA
Surgical reconstruction of the arch is now relatively straightforward;
▫ attention is increasingly focused on the preoperative identification and surgical management of the aortic valve and subaortic stenosis found in approximately one half of cases.
IAA CPB Considerations: Cannulation
• 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
• 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)
IAA CPB Considerations:
• 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)
IAA cardioplegia
The first cardioplegic administration is performed in the aortic root.
• Subsequent doses may be ostial
Aortic Coarctation Etiology
Coarctation is due to an abnormality in development of the embryologic left fourth and sixth aortic arches
• Congenital narrowing with varying degrees of hypoplasia can exist
Surgical Correction-coarctation
Balloon Aortoplasty
coarctation Surgical Correction
• Four predominant repairs:
- Left subclavian patch angioplasty • 2. Resection: End-to-end anastamosis • 3. Subclavian translocation • 4. Patch angioplasty
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
