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V. Hraška, P. Murín, Surgical Management of Congenital Heart Disease I, DOI:10.1007/978-3-642-24169-7_4, © Springer-Verlag Berlin Heidelberg 2012

Contents

Tetralogy of Fallot

Contents

◙ Introduction 152 ◙ Tetralogy of Fallot with Pulmonary Stenosis 153

◙ Anatomy 153 ◙ Indication for Surgery 154 ◙ Approach and Cardiopulmonary Bypass Strategy 154 ◙ Transatrial Approach with Release of the Right Ventricular Outflow Tract Obstruction 154

◙ The Goal of Surgery 154 ◙ Patient Characteristics 155 ◙ Specific Steps of Operation 155

◙ Transatrial Approach with Resection of the Right Ventricular Outflow Tract and Valvotomy of the Pulmonary Valve 159


◙ Transatrial Approach with a Mini-Transannular Patch 160 ◙ The Goal of Surgery 160 ◙ Patient Characteristics 160 ◙ Specific Steps of Operation 161

◙ Tetralogy of Fallot with Pulmonary Atresia and Ductus-Dependent Pulmonary Circulation 164

◙ Anatomy 164 ◙ Indication for Surgery 164 ◙ Transventricular Approach Preserving the Natural Connection of the Right Ventricle and Pulmonary Artery with Patch Enlargement of the Outflow Tract 164


◙ Direct Connection of the Pulmonary Artery and Right Ventriculotomy with Patch Enlargement of the Outflow Tract 168


152 V. Hraška, P. Murín

Introduction

Evidence suggests that early correction minimizes secondary damage to the heart or other organ systems due to chronic hypoxia, promotes pulmonary ar-tery growth, and alleviates the stimulus for continuous right ventricular hy-pertrophy, thus preserving the mechanical and electrical stability of the heart. In the majority of centers, therefore, primary repair is electively performed before 6 months of age. The strategy of primary repair provides excellent out-comes, with mortality approaching zero, and acceptable morbidity. Avoidance of a shunt also has economical and psychosocial advantages. A combination of transatrial and transpulmonary approach is the preferred method. An effort is made to preserve the pulmonary valve, thus potentially limiting the negative impact of pulmonary regurgitation on right ventricular function. The need for a transannular patch is determined by the hypoplastic pulmonary artery annulus, and it is not eliminated by the shunt procedure. If a transannular approach is unavoidable, excision and patching should be minimal to prevent the long-term adverse sequelae associated with right ventriculotomy, particularly in the pres-ence of pulmonary insufficiency. Depending on the institutional experience and policy, the staged approach remains a reasonable option.

◙ Tetralogy of Fallot with Absent Pulmonary Valve Syndrome 173 ◙ Anatomy 173 ◙ Indication for Surgery 173 ◙ Technique of Anterior Translocation of the Pulmonary Artery 173


◙ Recommended Reading 181

1534 Tetralogy of Fallot

Tetralogy of Fallot with Pulmonary Stenosis

Anatomy

The anatomic feature of the tetralogy of Fallot is underdevelopment of the subpulmonary infundibulum, therefore the “tetralogy” is in fact a “monology.” The abnormal superior, anterior, and leftward position of the infundibular sep-tum results in crowding of the right ventricular outflow tract, a nonrestric-tive malalignment-type ventricular septal defect, caused by non-occlusion of the infundibular septum with the left anterosuperior and right posteroinferior limbs of the septal band, varying degrees of overriding of the aorta, and ulti-mately, secondary hypertrophy of the right ventricle. The mechanism of the right ventricular outflow tract obstruction usually includes a combination of infundibular, valvar, and supravalvar obstruction. Isolated infundibular steno-sis is created by a prominent parietal band, which has a well-developed infun-dibular chamber and pulmonary artery. The right ventricular-pulmonary trunk junction, surgically called the annulus, is small and obstructive when there is diffuse infundibular hypoplasia and/or fibrosis surrounding the subvalvar area. A stenotic pulmonary valve is present in 75% of cases. The valve is frequently bicuspid, with tethering of the leaflets; a commissural fusion is less common. The pulmonary trunk is frequently waisted at the commissural attachments of the pulmonary valve, creating supravalvar narrowing. If there is no additional source of pulmonary blood flow (apart from the ductus arteriosus), the capac-ity of the pulmonary artery bed should be adequate. However, anomalies such as stenosis at the origin of the pulmonary arteries, narrowing of left pulmonary artery with ductal shelf, or an absent left pulmonary artery with ductus depen-dent perfusion can occur. Typically, the ventricular septal defect is classified as type 2, (perimembranous) conal septal malalignment, tetralogy type. When the infundibular septum is absent, the ventricular septal defect is subarterial. Coronary artery anomalies are seen in approximately 5–7% of the cases. From a surgical point of view, the most important aspect is the origin of the entire left anterior descending coronary artery from the right coronary artery, which crosses the infundibulum at a variable distance from the annulus. The conduc-tion system follows the same course as in other perimembranous ventricular septal defects. If there is a prominent posteroinferior limb of the septal band (trabecula septomarginalis), the conduction system is safely covered; other-


wise, the bundle of His penetrates the right fibrous trigone and courses for-ward toward the muscle of Lancisi, along the inferior margin of the defect.

Indication for Surgery

Elective primary repair of tetralogy of Fallot with pulmonary stenosis in asymptomatic patients is delayed beyond 3 months of age. In symptomatic patients, primary repair is performed irrespective of age, weight, and preopera-tive status.

In the vast majority of patients, the size of the pulmonary arteries is ad-equate for correction. In newborns, the pulmonary arteries are undistended due to diminished pulmonary blood flow; therefore, a diameter of about 3 mm is sufficient. However, there is small subset of patients in whom the pulmonary arteries are indeed diminutive, precluding closure of the ventricular septal de-fect. The staged approach using a shunt is considered if the preoperative status precludes using the pump. The small size of the pulmonary arteries is not an indication for a shunt, because if the pulmonary arteries are suitable for a shunt, they should also be adequate for correction.

Approach and Cardiopulmonary Bypass Strategy

The heart is approached through a median sternotomy. The standard technique of cardiopulmonary bypass with mild hypothermia (32°C) is used. A left ven-tricular vent is inserted through the entrance of the right pulmonary veins.

Transatrial Approach with Release of the Right Ventricular Outflow Tract Obstruction

The Goal of SurgeryWorking through the tricuspid valve, effective release of the right ventricular outflow tract obstruction is accomplished by transection of the parietal band. Subsequently, the ventricular septal defect and atrial septal defects are closed.


Patient Characteristics

Age at operation: 5 monthsDiagnosis: 1. Tetralogy of Fallot with infundibular stenosis2. Secundum atrial septal defect3. Restrictive ductus arteriosus 4. Down syndromeHistory: Failure to thrive, cyanosis

Procedure:1. Transatrial correction with patch closure of the

ventricular septal defect and resection of the right ventricular outflow tract obstruction

2. Direct closure of the atrial septal defect3. Clip on the patent ductus arteriosus

Specific Steps of Operation

Clip1

Echocardiogram and external anatomy of the heart.

Hans

Schreibmaschinentext

Hans

Schreibmaschinentext


Clip2

Dissection of the pulmonary arteries, closure of the ductus arteriosus. The aortic cross clamp was applied, and antegrade cold crystalloid cardioplegia was delivered. The pulmonary trunk was opened to inspect the pulmonary valve. The pulmonary valve was tricuspid, well developed and had no structural alterations.

Clip3

Release of the right ventricular outflow tract ob-struction.


Clip4

Patch closure of the ventricular septal defect.

Clip5

Closure of the atrial septal defect and pulmonary artery trunk.


Clip6

Postoperative findings.

fullversion



Age at operation: 5 monthsDiagnosis: 1. Tetralogy of Fallot with infundibular stenosis

and pulmonary valve stenosis2. Secundum atrial septal defect3. DiGeorge syndromeHistory: Elective surgery


ventricular septal defect and resection of the right ventricular outflow tract obstruction

2. Valvotomy of the stenotic pulmonary valve with patch enlargement of the pulmonary trunk

3. Direct closure of the atrial septal defect


Clip1

Commissurotomy of the stenotic bicuspid pulmo-nary valve, and transatrial correction, with patch closure of the ventricular septal defect.

Transatrial Approach with Resection of the Right Ventricular Outflow Tract and Valvotomy of the Pulmonary Valve

The Goal of SurgeryWorking through the pulmonary trunk and tricuspid valve, effective release of the right ventricular outflow tract obstruction is accomplished by transection of the parietal band and by pulmonary valve surgery. Subsequently, the ven-tricular septal defect and atrial septal defects are closed. The pulmonary trunk should be enlarged with a pericardial patch.



Age at operation: 2 monthsDiagnosis: 1. Tetralogy of Fallot with infundibular and

pulmonary valve stenosis (pulmonary annulus 5 mm in diameter)

2. Secundum atrial septal defect History: Progressive cyanosis


ventricular septal defect2. Mini-transannular patch enlargement of the

right ventricular outflow tract3. Direct closure of the atrial septal defect

Transatrial Approach with a Mini-Transannular Patch

The Goal of SurgeryThe need for transannular patch is determined by the severity of the right ven-tricular outflow tract obstruction. If the diameter of the pulmonary artery an-nulus is ≥ –3 Z, a mini-transannular patch is indicated. The short transannular ventriculotomy incision (5–10 mm in length) should avoid any conal branches of the right coronary artery. Only the parietal band is transected, preserving the moderator band. The ventricular septal defect is closed through the tricuspid valve. The geometry of the pericardial patch enlargement of the right ventricu-lar outflow tract should be consistent with the size of the normal pulmonary annulus. If there is stenosis at the origin of the left pulmonary artery or if there is ductal shelf, a patch plasty is needed. The mini-transannular patch technique can result in significantly less right ventricular dilatation and better preserva-tion of the right ventricular function in the long run.



Clip1


Clip2

Opening of the right ventricular outflow tract and transection of the parietal band.


Clip3


Clip4

Construction of the mini-transannular patch.


Clip5

Postoperative findings.

fullversion


Tetralogy of Fallot with Pulmonary Atresia and Ductus-Dependent Pulmonary Circulation

Anatomy

Tetralogy of Fallot with pulmonary atresia and ductus-dependent pulmonary circulation is the simplest form of pulmonary atresia with a ventricular sep-tal defect. The pulmonary arteries are reasonably well developed. The right ventricular outflow tract either terminates at an imperforate pulmonary valve or narrows to a blind end point. The infundibulum either is developed, but is hypertrophied, thus obstructing the outflow, or the infundibulum is nearly completely absent. In this case, the ventricular septal defect is subarterial, and the aortic valve is anteriorly located, very close to the free wall of the right ventricle. In any case, there is no luminal continuity between the right ventricle and the diminutive pulmonary trunk or the pulmonary arteries. The ductus ar-teriosus is usually long and tortuous.


Diagnosis is indication for surgery. Complete correction is preferable. If there is severe prematurity or any other preoperative risk factors contraindicating use of the pump, either stenting of the duct or shunt placement might be con-sidered.

Transventricular Approach Preserving the Natural Connection of the Right Ventricle and Pulmonary Artery with Patch Enlargement of the Outflow Tract

The Goal of SurgeryResection of obstructing muscles in the outflow and opening of the atretic valve is required to create a natural connection between the right ventricle and the pulmonary artery trunk. The outflow is subsequently reconstructed with a pericardial patch, with or without monocusp valve. The closure of the ventricu-lar septal defect is performed through the ventriculotomy.



Age at operation: 5 daysDiagnosis: 1. Tetralogy of Fallot with pulmonary atresia

(imperforate pulmonary valve)2. Patent ductus arteriosus3. Secundum atrial septal defect History:1. Prenatally diagnosed, elective indication for

surgery

Procedure:1. Transventricular correction with patch closure

of the ventricular septal defect2. Resection of the atretic valve and patch en-

largement of the right ventricular outflow tract and pulmonary trunk

3. Direct closure of the atrial septal defect4. Ligation of the patent ductus arteriosus


Clip1


Clip2

Opening of the right ventricular outflow tract and resection of the obstructing muscles – opening of the imperforated pulmonary artery valve.


Clip3

Transection of the obstructing muscles.

Clip4



Clip5

Reconstruction of the right ventricular outflow tract.

Clip6

Final result.

fullversion


Direct Connection of the Pulmonary Artery and Right Ventriculotomy with Patch Enlargement of the Outflow Tract

The Goal of SurgeryThe pulmonary artery is connected with the right ventriculotomy, either directly or by conduit. In newborns, it is nearly always possible to achieve direct, tension-free connection of the pulmonary artery with the right ventricle after thorough mo-bilization of the pulmonary arteries. Subsequently,

the outflow is reconstructed with a pericardial patch. If a conduit is necessary, a pulmonary ho-mograft or bovine jugular vein conduit is prefer-able. The closure of the ventricular septal defect is performed through the ventriculotomy.


Age at operation: 18 daysDiagnosis: 1. Tetralogy of Fallot with pulmonary atresia 2. Patent ductus arteriosus3. Secundum atrial septal defect History:1. Prenatally diagnosed, elective surgery

Procedure:1. Transventricular correction with patch closure

of the ventricular septal defect2. Direct connection of the pulmonary artery

with the right ventriculotomy, with patch en-largement of the right ventricular outflow tract and pulmonary trunk

3. Direct closure of the atrial septal defect4. Transection of the patent ductus arteriosus



Clip1

Preoperative echocardiogram.

Clip2

Mobilization of the pulmonary arteries, transection of the ductus arteriosus.


Clip3

Transection and opening of the pulmonary trunk and the left pulmonary artery.

Clip4

Ventriculotomy and transection of the parietal band.


Clip5


Clip6

Reconstruction of the right ventricular outflow tract.


Clip7

Final results of reconstruction.

fullversion


Tetralogy of Fallot with Absent Pulmonary Valve Syndrome

Anatomy

The absent pulmonary valve syndrome is very rare, accounting for 3–6% of all patients with tetralogy of Fallot. Apart from the intracardiac anatomy typical of tetralogy of Fallot, the pulmonary annulus is mildly to moderately hypoplastic, with vestigial nubbins of nonfunctional myxomatous tissue rather than devel-oped valve cusps. However, the distinctive feature is the airway obstruction due to tracheobronchial compression that results from massive dilatation of the main pulmonary artery and its first- and second-order branches and from the abnormal branching of the segmental arteries. Consequential tracheomalacia and bronchomalacia determine the timing and severity of respiratory compro-mise, as well as the morbidity and mortality of these patients. A patent ductus arteriosus is never present.


Early primary repair should always be considered. Symptomatic patients need to proceed directly to surgery, and asymptomatic patients should undergo re-pair early enough to minimize the potentially harmful effect of dilated pulmo-nary arteries on the tracheobronchial tree. These patients are operated on an elective basis, between 3 and 6 months of age.

Technique of Anterior Translocation of the Pulmonary Artery

The Goal of SurgeryThe first goal of surgery is the correction of the tetralogy of Fallot, using either the trans-atrial or the transventricular approach. The second, very specific goal is to decompress the airways from the dilated pulmonary arteries. The classical ap-proach to decompression of the airways has focused on plication and reduction of the anterior or posterior wall of the normally positioned pulmonary arteries or on replacing the aneurysmatic pulmonary arteries by pulmonary homograft. Alter-natively, one can translocate the pulmonary artery anterior to the aorta and away


from the tracheobronchial tree. This technique has the potential to reduce or eliminate bronchial com-pression. One should keep in mind that only dilated right and left pulmonary arteries, up to the hilum, are amenable to surgery. Abnormalities of arborization, with tufts of arteries encircling and compressing the intrapulmonary bronchi, cannot be addressed dur-ing surgery. This could partially explain the high

mortality rate of the youngest, symptomatic group of patients. Particularly in symptomatic patients, insertion of a valve homograft with anterior and/or posterior plication of the pulmonary arteries should also be considered, in order to decrease the wall ten-sion and prevent later development of aneurysmal dilatation of the pulmonary arteries.


Age at operation: 1 monthDiagnosis: 1. Tetralogy of Fallot with absent pulmonary

valve syndrome2. Secundum atrial septal defect History: Since-birth repeated respiratory infections, other-wise circulatory stable

Procedure:1. Transatrial correction with patch closure of

ventricular septal defect2. Anterior translocation of the pulmonary arter-

ies above the aorta and direct connection with the right ventricular outflow tract

3. Direct closure of the atrial septal defect


Clip1

Preoperative echocardiogram.


Clip2

The ascending aorta, aortic arch, and brachioce-phalic vessels are widely mobilized. The superior vena cava is dissected free, and the azygos vein is transected to improve mobility of the superior vena cava.

Clip3

The standard technique of cardiopulmonary bypass with full flow and mild hypothermia (32°C) is employed. Myocardial protection is provided by crystalloid antegrade cardioplegia.


Clip4

Repair of the tetralogy of Fallot is undertaken first.

Clip5

A short, vertical incision is made in the infundibu-lar portion of the right ventricle. Subsequently, the pulmonary artery trunk is transected above the annulus.


Clip6

After another dose of cardioplegia, the aorta is transected just above the commissures. At this point, one should consider shortening the aorta by resecting the appropriate tubular segment to facili-tate an anteposition of the pulmonary artery.

Clip7

The pulmonary artery is brought anteriorly.


Clip8

The end-to-end anastomosis of the ascending aorta is performed.

Clip9

Direct connection between the obliquely shortened pulmonary trunk and the right ventricular outflow tract is accomplished.


Clip10

Complementary anterior–posterior downsizing of the pulmonary arteries is performed to decrease wall tension and prevent later development of an-eurysmal dilatation of the pulmonary artery.

Clip11

Final result.


Clip12

Postoperative echocardiogram.

fullversion


Recommended ReadingApitz Ch, Anderson RH, Redington AN (2010) Tetralogy of Fallot with pulmonary stenosis. In: Anderson RH, Becker EJ, Penny D et al (eds) Pediatric cardiology, 3rd edn. Churchill-Livingstone, London, pp 753–774

Bacha EA, Scheule AM, Zurakowski D et al (2001) Long-term results after early primary repair of tetralogy of Fallot. J Thorac Cardiovasc Surg 122:154–161

Becker EJ, Anderson RH (2010) Tetralogy of Fallot with pul-monary atresia In: Anderson RH, Becker EJ, Penny D et al (eds) Pediatric cardiology, 3rd edn. Churchill-Livingstone, London, pp 775–794

Chowdhury UK, Sathia S, Ray R et al (2006) Histopathology of the right ventricular outflow tract and its relationship to clinical outcomes and arrhythmias in patients with tetralogy of Fallot. J Thorac Cardiovasc Surg 132:270–277

Hirsch JC, Mosca RS, Bove EL (2000) Complete repair of te-tralogy of Fallot in the neonate: results in the modern era. Ann Surg 232:508–514

Hraška V (2000) A new approach to correction of tetral-ogy of Fallot with absent pulmonary valve. Ann Thorac Surg 69:1601–1603

Hraška V (2005) Tetralogy of Fallot with absent pulmonary valve syndrome using a new approach. Pediatr Cardiac Surg Annul Semin Thorac Cardiovasc Surg 8:132–35

Hraška V (2007) Absent pulmonary valve repair. Op Tech Tho-rac Cardiovasc Surg 12:36–46

Hraška V, Photiadis J, Schindler E et al (2009) A novel approach to the repair of tetralogy of Fallot with absent pulmonary valve and the reduction of airway compression by the pulmonary artery. Semin Thorac Cardiovasc Surg Pediatr Card Surg Ann 12:59–62

Hraška V, Murín P, Photiadis J et al (2010) Surgery for tetral-ogy of Fallot – absent pulmonary valve syndrome. Technique of anterior translocation of the pulmonary artery. MMCTS. doi:10.1510/mmcts.2008.003186

Jacobs ML (2000) Tetralogy of Fallot. Annals 69(Suppl):S77–S82

Jonas RA (2004) Tetralogy of Fallot with pulmonary stenosis. In: Jonas RA (ed) Comprehensive surgical management of con-genital heart disease. Arnold, London, pp 279–300

Kantorova A, Zbieranek K, Sauer H et al (2008) Primary early correction of tetralogy of Fallot irrespective of age. Cardiol Young 18:153–157

Karl TR, Sano S, Pornvilliwan S et al (1992) Tetralogy of Fallot: favorable outcome of non-neonatal transatrial, transpulmonary repair. Ann Thorac Surg 54:903–907

Ooi A, Moorjani N, Baliulis G et al (2006) Medium term out-come for infants in tetralogy of Fallot: indications for timing of surgery. Eur J Cardiothorac Surg 30:917–922

Pigula FA, Khalil PN, Mayer JE, del Nido PJ, Jonas RA (1999) Repair of tetralogy of Fallot in neonates and young infants. Cir-culation 100(Suppl):S157–S161

Reddy VM, Liddicoat JR, McElhinney DB et al (1995) Rou-tine primary repair of tetralogy of Fallot in neonates and infants less than three months of age. Ann Thorac Surg 60(6Suppl):S592–S596

Redington AN (2006) Physiology of right ventricular failure. Semin Thorac Cardiovasc Surg Pediatr Card Surg Ann 9:3–10

Seliem MA, Wu YT, Glenwright K (1995) Relation between age at surgery and regression of right ventricular hypertrophy in te-tralogy of Fallot. Pediatr Cardiol 16:53–55

Steward RD, Backer CL, Young L et al (2005) Tetralogy of Fal-lot: results of a pulmonary valve-sparing strategy. Ann Thorac Surg 80:1431–1438

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