Tricuspid Atresia

Seoul National University Hospital

Department of Thoracic & Cardiovascular Surgery

Tricuspid Atresia

1. Definition Congenital cardiac malformation in which the right atrium fail to open into a ventricle through an A-V valve. The atrial situs is almost solitus in association with a ventricular D-loop, and right ventricle is hypoplastic.

2. History Kuhne : Recognized entity in 1906 Bellet : Description of clinical feature in 1933 Glenn : Glenn shunt in 1958 Fontan : Successful repair in 1968 Kreutzer : Modification in 1973

Tricuspid Atresia

Pathophysiology • Atretic tricuspid valve, hypoplastic right ventricle, ASD,

VSD and restricted pulmonary blood flow(70%) lead to right-to-left shunting and cyanosis.

• In patients with unrestricted pulmonary blood flow (30%), pulmonary overcirculation and congestive heart failure develop.

• Manifestations of left ventricular volume overload (e.g., ventricular dilation, mitral regurgitation, ventricular dysfunction) result from combined systemic and pulmonary venous return.

Tricuspid Atresia

• Deoxygenated blood

• Oxygenated blood

Hemodynamics

Tricuspid Atresia

Surgical Morphology 1. Types of atresia . Muscular : 75% . Membranous Fibrous diaphragm Ebstein variant A-V canal defect variant ; rarer variant 2. Origin of great arteries . Ventriculoarterial concordant : 60~70% . Ventriculoarterial discordant : 30~40% . DORV, DOLV, single outlet with truncus : rarely 3. Others . Abnormality of mitral valve & LV ; high . Juxtaposition of atrial appendage in 11%

Classification of Tricuspid Atresia

1. TA with normal origin of great arteries (type I) . ASD always (4% restrictive) Uncommonly ostium primum defect . Obstruction to pulmonary blood flow : 85% (atretic in 10%) . LSVC (15%), LSVC to LA (1~5%)

2. TA with transposition of great arteries (Type II) . D-malposition, uncommonly L-malposition (Type III) . ASD always (small in 50%) . Lt. atrial juxtaposition (10%), CoA (30%), IAA (rare) . Pulmonary blood flow Usually large flow Subpulmonic stenosis (20~30%, rarely atretic)

Classification of TA

Most frequent

Clinical Features & Diagnosis

1. Symptoms & signs . Usually cyanosis, dyspnea, hypoxic spell depends on severity of PS

. Clubbing in childhood

. Excessive pulmonary flow with mild cyanosis & CHF in minority

. Harsh ejection systolic murmur in most patients

2. Chest radiography . Variable, depends on pulmonary blood flow

3. Electrocardiography . LAD, LVH, abnormal P-wave

4. Echocardiography

5. Cardiac catheterization & cineangiography

Natural History of TA

1. Incidence 1~3% of CHD 2. Survival 1) Normal origin of great arteries . With PS : 10% survival in one year Rapid narrowing of VSD : progressive cyanosis . Without PS : 10% survival in 10 years Congestive heart failure Narrowing of VSD : increasing cyanosis

2) Transposed great arteries . Without PS : almost dead in one year Tendency to close of VSD : subaortic stenosis . With PS : 50% survival in 2 years Narrowing of VSD is slower 3. Modes of death . Hypoxia, LCO in young . Volume overload & hypoxia : cardiomyopathy in old

TricuspidAtresia

Muscular atresia

TricuspidAtresia

VSD

RV

LV

TricuspidAtresia

Membranous atresia

Operative Techniques of TA

1. General plan of Fontan operation . Risk of thrombosis around catheter . Coronary sinus to pulmonary venous chamber . Pericardiopleural window

2. Procedures . Systemic-pulmonary artery shunting . Pulmonary artery banding . Bidirectional superior cavopulmonary shunt . Hemi-Fontan operation . Fontan operation by right atrial-pulmonary artery connection . Fontan operation by total cavopulmonary connection with or without incomplete atrial partition . Total cavopulmonary connection with extracardiac conduit

Repair for Systemic Obstruction

• Repair of hypoplastic aortic arch and pulmonary trunk band placement via thoracotomy

Repair for Systemic Obstruction

• Construction of proximal pulmonary trunk to aortic anastomosis ( Damus-Kaye-Stansel operation ) for systemic outflow tract obstruction

Repair for Systemic Obstruction

• Direct relief of subaortic obstruction in the univentricular heart with transposed great arteries ( VSD extension )

Bidirectional Cavopulmonary Shunt

Hemi-Fontan Operation

Fontan OperationLateral Tunnel

Fontan OperationExtracardiac Conduit

Results of Palliative Operation

1. Systemic pulmonary artery shunting 2. Pulmonary artery banding 3. Glenn operation Pulmonary A-V fistula

4. Incomplete ( partial ) Fontan operation BCPC ( SVC, IVC )

Hemi - Fontan operation

Fontan operation with deliberately incomplete

atrial partitioning

Results of Fontan Operation

1. Survival ; Early & time-related survival 2. Modes of death ; Early & Late 3. Incremental risk factors for death 4. Functional & hemodynamic status 5. Cardiac rhythm 6. Abnormality of pulmonary circulation 7. Protein-losing enteropathy 8. Thromboembolic complication 9. Neurologic complications 10. Desaturation after Fontan operation 11. Reoperation

Incremental Risk Factors for Death

1. Acute ventricular decompression

2. Late pulmonary & ventricular deterioration

3. Age at operation

4. Cardiac morphology

5. Pulmonary artery size

6. PA pressure & PVR

7. Ventricular hypertrophy

8. Atrial isomerism

9. RA-PA connection technique

Operative Indications for TA

1. Indications for palliative procedure . Shunt procedure . Banding

2. Indications for Fontan operation Indicated in whom one ventricle is too small or dysplastic or both, be unable to generate pulmonary or systemic blood flow . Optimal Age : 18 ~ 30 months of age (early : 10~12 months) . Hemi - Fontan or BCPC around 6 months of age . PVR 4units more : contraindicated . Ventricular end-diastolic pressure of greater than 15mmHg ,

important A-V valve incompetence , or EF of less than 45% raises a question of suitability

Special Situations & Controversies

• Types of operation for tricuspid atresia• Valved Fontan pathway• Persistent left superior vena cava with he

miazygos extension of inferior vena cava No longer Kawashima variant• Ideal Fontan technique Currently, extracardiac conduit or lateral tunnel Fontan variants are preferred