Transcript Atrial Septal Defect

Atrial Septal Defect
Seoul National University Hospital
Department of Thoracic & Cardiovascular Surgery
Atrial Septal Defect
1. Definition
A hole of variable size in the atrial septum.
A patent foramen ovale functionally closed is excluded.
Partial anomalous pulmonary venous connections may
occur as isolated lesion or in combination with ASD.
2. History
Roesler : ASD diagnosed during life in 1934.
Bedford : Diagnosis of ASD clinically in 1941.
Winslow : Description of PAPVC in 1739.
Murray : External suture of ASD in 1948.
Lewis & Taufic
: 1st open repair with inflow stasis
and cooling in 1953.
Gibbon : 1st open heart surgery in 1953.
Composition of Atrial Septum
1. Thick superior portion derived from infolded atrial
roof that forms the secondary atrial septum of the
embryo, this terminates in the superior limbic bands.
2. Thin lower portion derived from the septum primum
which extends superiorly and to the left of the limbus.
The lower edge of the septum primum normally fuses
with developing endocardial cushions.
Atrial Septal Defect
Pathophysiology
• Atrial septal defects permit left-to-right
shunting, increasing pulmonary blood flow.
• Over time, the increased pulmonary
overcirculation leads pulmonary vascular
occlusive disease, pulmonary hypertension,
right ventricular failure, and the atrial
arrhythmias.
Anatomy of Right Atrium
ASD . Surgical Pathology
Atrial Septal Defect
Types
 Fossa ovalis defect (ostium secundum defect)
 Posterior defect
 Ostium primum defect
 Coronary sinus defect
 Subcaval defect (sinus venosus defect ,
superior vena caval defect)
 Confluent ASD
Types of Atrial Septal Defect
ASD . Gross Morphology
ASD. Secundum, Large
ASD. Secundum, Multiple
ASD. Secundum
ASD. Sinus Venosus Type
ASD. Sinus Venosus Type
ASD. Sinus Venosus Type
Pericardial Patch Closure
ASD. Sinus Venosus Type
Types of PAPVC
1. Sinus venosus malformation (syndrome)
2. Right superior pulmonary vein to SVC
without superior caval ASD
3. Rt. PVs to Rt. atrium with or without ASD
4. Rt. PVs to IVC (Scimitar syndrome)
5. Rare connections of Rt. PVs
6. Anomalous Lt. PV connections
7. Bilateral partial anomalous PV connection
Pathophysiology of PAPVC
• One or more, but not all, all the pulmonary
veins drain into the right atrium or its venous
tributaries ; ASDs are commonly associated.
• This anomaly results in a left-to-right shunt
leading to pulmonary hypertension, pulmonary
vascular disease, and congestive heart failure if
left untreated.
• It comprises less than 1% of congenital heart
diseases.
Morphology of Atrial Septal Defect
1. Cardiac chamber
. Enlarged thick right atrium
. Increased diastolic RV
. LV dynamic abnormality
2. Mitral valve
. Mitral prolapse
. Mitral incompetence
. Cleft mitral leaflet
3. The lungs
. Pulmonary vascular disease
. Compress smaller airways
4. Cardiac conditions
. All varieties of CHD coexist
. Mitral valvar disease
. Tricuspid incompetence
5. Other conditions
. Marfan
. Turner
. Noonan
. Holt-Oram syndrome
. Rarely all these conditions
Clinical Features & Diagnosis
1. Prevalence
. 10% of CHD
.M : F = 1 : 2
. Fossa ovalis defect is most common (80%)
2. Symptoms and signs
. No symptoms & signs when Qp/Qs is less than 1.5
. Effort breathlessness and respiratory infections
. Active parasternal systolic lift & fixed splitting of S2
3. Chest radiography, electrocardiography
4. Two-dimensional echocardiography
5. Cardiac catheterization and cineangiography
Natural History of ASD
1. Survival
5-15% die in 3rd decade
Premature death with CHF
Rarely paradoxical emboli
2. Pulmonary hypertension
3. Functional status
1% with large ASD have
symptoms during 1 year
4. Spontaneous closure
Uncommon after 1 year
5. Changes in Qp/Qs with time
6. Rt & Lt ventricular function
7. AV valvar dysfunction
8. Supraventricular arrhythmia
AF in adult
Sinus node dysfunction
9. Systemic hypertension
No definite causes,
but increased incidence
Changes of Qp/Qs in ASD
• Decreasing LV compliance may increase Qp/Qs in
patients with ASD during 5th – 6th decades
• Systemic arterial hypertension may accelerate this
process and unmask an ASD
• Most ASDs increase in size & shunt as time passes,
as with tendency toward mitral valve prolapse
• These increase in shunt with time do not occur when
the shunt is from the PAPVC without ASD
• Qp/Qs decreases when the pulmonary hypertension
develops with decreased RV compliance with RVH
Ventricular Functions in ASD
• Right ventricular volume overload and increased RV
diastolic dimensions are characteristic, and the
ventricular septum is displaced posteriorly and leftward
• These features of RV are well tolerated much longer than
volume-overloaded LV, volume-overloaded RV by acute
tricuspid or pulmonary regurgitation
• RV failure eventually occurs, however, with decreased
RV ejection fraction and hypokinesia
• Most adult patients with large ASD have normal LV
systolic dimensions but subnormal diastolic dimensions
• Some loss of LV functional reserve is present in most
adult patients and in some children & preoperative LV
abnormalities by the effects of volume-overloaded RV
Indications for Operation
1. Uncomplicated ASD or PAPVC, RV volume overload
& Qp/Qs greater than 1.5 in uncomplicated ASD
2. Scimitar syndrome with severe hypoplasia of Rt lung
and Qp/Qs less than 2 is not an indication.
3. Isolated PAPVC without ASD, when Qp/Qs is less than
1.8 is not an indication.
4. Optimal age is under 5 years of age and also can be
considered to be 1-2 years of age recently.
5. Pulmonary vascular disease of sufficient severity
(8-12u) is not indicated.
Techniques of Operation
1. Repair of fossa ovalis type
2. Repair of posterior ASD
3. Repair of coronary sinus type
4. Repair of sinus venosus type
5. Repair of anomalous PV connections
6. Repair of mitral or tricuspid valve disease
Primary Closure of ASD
Patch Closure of Secundum ASD
Sinus Venosus Type of ASD
Sinus Venosus Type with PAPVC
Sinus Venosus Type with PAPVC
Warden Operation
Warden Operation
Repair of PAPVR
Connection Left Pulmonary Vein to Innominate Vein
• Anastomosis of left pulmonary vein to left atrial appendage
Perforated Flap-valve Patch
Operation for Scimitar Syndrome
• Direct anastomosis of Scimitar vein to LA
Features of Postoperative Care
1. Convalescence of most patients is uneventful.
2. Unusually high LA pressure in early after operation
in older patients because of impaired ventricular
function
3. Incidence of pulmonary & systemic embolization occur,
anticoagulation for 8-12 weeks in old patients
4. When mitral regurgitation has been underestimated
preoperatively and there are signs of pulmonary
venous hypertension, urgent evaluation & reoperation
for valve is required
Special Situations & Controversies
1. Closure of ASD by percutaneous technique
2. Need for cold cardioplegic myocardial protection
3. Direct suture versus patch repair
Patch closure of large defects to avoid excessive tension
4. Patch material in the atrial septum
5. Complications of sinus venosus syndrome
Postoperative narrowing due to small size or patch
Compromise of sinus node by suture retraction
Development of junctional rhythm by junctional incision
. V-Y atrioplasty
. Warden operation
Choice of Intraatrial Patch
Autologous pericardium
• When a regurgitation jet may strike the patch
• When pericardium forms part of the wall of
an intracardiac conduit, the precise contour
(position) of which is determined by pressure
difference
• When the patch is sewn to a very delicate area
Operative Results of ASD
1. Survival
. Hospital mortality
. Time-related survival
4. Functional status
5. Hemodynamic results
2. Modes of death
6. Ventricular function
3. Incremental risk factors
7. Arrhythmic events
for death
1) Pulmonary vascular
disease (contraindication
more than 6~8 units)
2) Older age at operation
3) Anatomic type
8. Thromboembolism
9. Reinterventions