Double outlet right ventricle

History, Anatomy, Embryology, Types, Clinical Features, Hemodynamics, evaluation (X Ray, ECG, 2D ECHO, ANGIOGRAM) and Management (MEDICAL and SURGICAL).

1. Double Outlet Right Ventricle Embryology, Anatomy, Hemodynamics , Clinical presentation, and Management By: Himanshu Rana

2. DORV ‘the great Chameleon’

3. Introduction Newfield et al – Both great arteries arise exclusively from RV, neither semilunar valve in fibrous continuity with either AV valve & VSD is usually present as the only outlet from LV Pulmonary valve or sub-pulmonary stenosis may be present or absent. Lev et al. One complete and at least half of the other arterial trunk emerge from RV, and there may or may not be mitral-aortic or mitral-pulmonary continuity Definitions:

4. Introduction Van Praagh et al – Relied on subaortic and subpulmonary conus to produce mitral discontinuity as diagnostic marker. Kirklin - Malformation in which the whole of one great artery and more than half of the other originates from the right ventricle Anderson and his colleagues ( Tynan et al) abnormal ventriculoarterial connection with more than half of each great artery originating above the morphologic RV .

5. HISTORY

6. HISTORY Cond…

7. Incidence <1% of CHD 0.06 case per 1000 live birth No sexual or racial predilection No associated Genetic defect identified Mostly sporadic, 22q11 deletion associated with some cases DORV

8. Goor & Edwards : - “DORV appears to represent a primitive embryologic condition because of failure to achieve cono-truncal rotation and left shift of the conus .” EMBRYOLOGY (Old theory…)

9. EMBRYOLOGY Cont ….

10. EMBRYOLOGY Cont ….

11. EMBRYOLOGY Cont ….

12. CONUS : A circular tube of muscle, upon which semilunar valve sits up. One conus is absorbed normally. The remaining conus grows & pushes the great vessel superiorly and anteriorly & is always connected to the RV. In DORV, absorption of both coni fails & both great vessels are connected to RV. TGA – aortic conus persists DOLV – both coni absorbed TOF – Pulmonic conus persists but there is anterior deviation of the conal septum. Van Praagh called it as Monology of Stenson . EMBRYOLOGY Contd ….

13. Van praagh theory of conal underdevelopment “ the distal or semilunar part of infundibulum or conus arteriosus performs an arterial switch during cardiogenesis ” EMBRYOLOGY Cont ….

14. Van Praagh classification of DORV Type I DORV : Isolated conotruncal anomaly Type II DORV : Conotruncal anomaly with malformations of AV valve & ventricles Type III DORV : Heterotaxy syndromes ( Polysplenia , asplenia )

15. DORV represent a part of the whole spectrum of cono-truncal anomaly Spectrum of cono-truncal anomalies A P VSD TOF DORV TGA (double coni ) A P P P P A A A R L

16. PATHOLOGIC CLASSIFICATION Location of VSD to great arteries Based on Great artery relationship

17. Ventricular septal defect Often the only outflow tract of the left ventricle Mostly cono -ventricular VSD in peri -membranous septum. Due to persistence of the bulbo -ventricular canal. Accordingly, DORV is classified w.r.t. VSD location as: Sub-aortic, Sub-pulmonary, Doubly committed & Non committed.

18. Sub-aortic type(40%) Sub-pulmonary type ( Taussig Bing complex)(20%) Doubly committed(10%) Remote type(<10%) POSITION OF VSD

19. GREAT ARTERY RELATIONSHIPS AT THE LEVEL OF SEMILUNAR VALVES Right posterior aorta A ortic valve & trunk originate from RV post. & to the rt. of pulmonary valve. Right lateral aorta (side-by-side relationship) Aorta is to the rt. of PA., & the semilunar valves lie approximately in the same transverse & coronal plane. The classically described great artery relationship in DORV.

20. Right anterior aorta (D-malposition) A orta is to the rt. & ant. to PA or may be directly ant. Left anterior aorta (L-malposition) A orta is to the lt. & ant. to PA. Least common.

21. 4 x 4 TYPES OF DORV, AND MORE… 16 possible variations of DORV based on the great artery relationships and the location of the VSD In addition, an intact ventricular septum allows four other possible types of DORV, depending on the great artery relationships

22. ASSOCIATED ANOMALIES Pulmonary Stenosis - most common – 40-70% (50%), - frequently co-exists with sub-aortic VSD (80%); - bicuspid pulmonary valve; - rarely seen in sub-pulmonary VSD type.

23. ASSOCIATED ANOMALIES Subaortic stenosis – 3%; common in sub-pulmonic VSD(50%) Coarctation – 12%; common in sub-pulmonic VSD (50%). Mitral valve anomalies 10%; Common in remote VSD ASD – os type 25% of all DORV, TAPVC – 2% AV canal – 5%, Common in remote VSD.

24. CORONARY ANOMALIES (10%) Similar to TOF – LAD from RCA (mc) Similar to TGA – RCA from the right posterior aortic cusp & LCA from the left posterior cusp Anomalous origin of the L Cx from RCA , Single coronary ostium , origin of RCA from LCA .

25. DORV – MAJOR CLINICAL PATERNS Group 1 – Sub-aortic VSD with PS ( resembles TOF ) (MC-40%) Group 2 – Sub-pulmonary VSD, with or without PS ( resembles TGA ). 20%; AKA T-B anomaly Group 3 – Sub-aortic VSD, no PS, ( resembles VSD ) (< 5%) Group 4 – Sub-aortic VSD with PVOD ( Resembles Eisenmenger –complex)

26. DORV ‘the great Chameleon’

27. SUB AORTIC VSD WITH PS RV aorta LV aorta Aortic saturation decreased PBF decreased Resemble TOF 50 % of sub-aortic VSD type have PS which is usually progressive HEMODYNAMICS

28. SUBPULMONARY VSD LV pulmonary trunk RV aorta Pulmonary saturation > Aortic If PVR decreased good aortic saturation; LV volume overload If PVR increases Blood from LV and RV Aorta Aortic saturation decreases. DORV with Sub pulmonic VSD AKA Taussig Bing anomaly & resembles TGA HEMODYNAMICS contd …

29. - Resembles VSD - PBF increased -Aortic saturation is normal. SUBAORTIC VSD WITH DECREASE PVR WITH NO PS HEMODYNAMICS contd …

30. SUBAORTIC VSD – INCREASE PVR -Increased blood to aorta -Decreased flow to pulmonary trunk -Aortic saturation falls Resembles Eisenmengers syndrome HEMODYNAMICS contd …

31. CLINICAL FEATURES

32. GROUP 1 : SUBAORTIC VENTRICULAR SEPTAL DEFECT AND PULMONARY STENOSIS Features similar to TOF PS is severe- early cyanosis, failure to thrive, exertional dyspnea, squatting, plethora due to polycythemia Cyanosis clubbing may be evident.

33. GROUP 1 : SUBAORTIC VENTRICULAR SEPTAL DEFECT AND PULMONARY STENOSIS.. The precordium show evidence of a right ventricular impulse at the left sternal border, prominent systolic thrill upper left sternal border due to obligatory flow across the bulbo -ventricular foramen VSD Grade 4 to 5/6 systolic ejection murmur, which radiates into the lung fields The first heart sound is normal, and the second heart sound is usually single.

34. GROUP 2 : SUBPULMONARY VENTRICULAR SEPTAL DEFECT Features resembling those in TGA with VSD . These patients present with cyanosis and heart failure in early infancy. When PS is also present, the cyanosis and polycythemia may be more severe

35. GROUP 2 : SUBPULMONARY VENTRICULAR SEPTAL DEFECT.. A precordial bulge and right ventricular impulse are present at the left sternal border. A grade 2 to 3/6 high-pitched systolic murmur may be present at the upper left sternal border. .

36. GROUP 2 : SUBPULMONARY VENTRICULAR SEPTAL DEFECT.. When PS is present, a systolic thrill may be present, and the murmur is loud (grade 3 to 4/6 ). The second heart sound is loud and single because of the proximity of the aorta to the chest wall With increased pulmonary flow, an apical diastolic rumble may be present.

37. GROUP 3 : SUBAORTIC VENTRICULAR SEPTAL DEFECT WITHOUT PULMONARY STENOSIS Patients present features typical of those with a large VSD and pulmonary hypertension. Usually, little cyanosis is evident, but failure to thrive and heart failure are dominant features. With increased pulmonary flow, respiratory tract infections are frequent.

38. GROUP 3 : SUBAORTIC VENTRICULAR SEPTAL DEFECT WITHOUT PULMONARY STENOSIS.. A systolic thrill may be present at the upper left sternal border, and a grade 3 to 4/6 holosystolic murmur may be evident at the left sternal border. An apical diastolic rumble and a third heart sound are audible at the cardiac apex.

39. GROUP 4 : SUBAORTIC VENTRICULAR SEPTAL DEFECT WITH PULMONARY VASCULAR OBSTRUCTIVE DISEASE Pulmonary flow is reduced, and heart failure and frequent respiratory infections are less evident. Cyanosis and clubbing may be present .

40. GROUP 4 : SUBAORTIC VENTRICULAR SEPTAL DEFECT WITH PULMONARY VASCULAR OBSTRUCTIVE DISEASE On examination, The systolic murmur may be diminished or absent The second sound is very loud and single. A decrescendo diastolic murmur of pulmonary valve insufficiency may be present .

41. Natural History Infant without PS may develop severe CHF Later PVOD Spontaneous closure of VSD – fatal, rare When PS present ,complications of CCHD - (Polycythemia, CVA) Taussig Bing –severe PVOD develop early as in TGA Associated anomalies COA LV hypoplasia poor prognosis

42. ELECTROCARDIOGRAPHIC FEATURES Right ventricular hypertrophy and right-axis deviation are the most common features Combined ventricular hypertrophy - markedly increased pulmonary flow (observed in patients with sub-pulmonary VSD). First-degree AV conduction delay is a common feature; however, it is not uniformly observed.

43. ELECTROCARDIOGRAPHIC FEATURES Right atrial enlargement -patients with PS left atrial enlargement may be observed in instances of increased pulmonary flow with intact atrial septum. Patients with complete AV septal defect associated with DORV also typically have left axis deviation, combined ventricular hypertrophy, atrial enlargement, and first-degree AV conduction delay .

44. ECG showing peaked right atrial P waves in leads2 and V1. q waves appear in lead 1 and aVL despite right axis deviation . Right ventricular hypertrophy manifested by tall R waves in leads V1 and aVR . The qR pattern in leads V5-6 indicates that left ventricle is well developed, in a case of DORV with subaortic VSD and severe PS .

45. ECG showing deep S wave in V5-6 indicating right ventricular hypertrophy. Biventricular hypertrophy is manifested by large RS complexes in leads V3-6, in a case of DORV, subaortic VSD .

46. ECG showing peaked right atrial P waves in leads 2,3, aVF . The QRS axis is rightward. Right ventricular hypertrophy is reflected by tall R waves in leads V1-2 and in leads aVR and by prominent S waves in left precordial leads, in a case of DORV and subpulmonary VSD.

47. ECG Distinguishing points from TOF Counter clockwise initial force with q waves in leads I & aVL , even when the axis is vertical or rightward. Deep & prolonged terminal force with broad, slurred S waves in leads I, aVL & V5-V6 and broad R wave in lead aVR . TOF

48. CHEST X RAY In patients with PS Features may resemble TOF Mild degree of cardiomegaly Pulmonary vascularity is diminished ( oligemia ) MPA segment is absent, resulting in concave upper left border of heart

49. DORV subaortic VSD with PS

50. DORV subaortic VSD pulmonary atresia

51. In cases of subaortic VSD without PS - Generalized cardiomegaly Prominent main pulmonary artery segment Increased pulmonary vascularity

52. DORV with sub-aortic VSD

53. Taussig Bing anomaly

54. When PVR is high - Prominent MPA peripheral pruning

55. ECHO 4 OBSERVATIONS REQUIRED FOR DIAGNOSIS Origin of one great vessel and overlie of at least 50% of the other great artery over the RV Mitral – semilunar discontinuity with conus Absence of LVOT other than VSD Spatial relationship of great arteries determined by bifurcation of pulmonary artery and branching of aorta .

56. DORV: Aortic-mitral Discontinuity LA LV RV Ao

57. VSD AO. LA CONUS RV L V DORV with Sub-aortic VSD

58. DORV with Sub-aortic VSD VSD AO. LA

59. DORV with sub-pulmonic VSD

60. DORV with doubly committed VSD

61. Echo Evaluation of DORV : Role of Echocardiography in Planning Sx Strategy: The crucial question: IS TWO VENTRICLE REPAIR FEASIBLE? Two ventricle repair is preferred over the single ventricle ( Fontan ) option whenever feasible: Better long term survival Less arrhythmias Better functional capacity

62. Role of Echocardiography In Planning Surgical Strategy: Criteria for Two Ventricle Repair Two good-sized ventricles No straddling of either of the AV valves The VSD should be suitably located for intra-ventricular re-routing No significant AV valve tissue in the way between VSD and the aorta

63. Echo Evaluation of DORV : Two Ventricle Repair Candidates- Additional Issues Branch PAs Origin of LAD in the TOF type of DORV The origin of coronary arteries in the Taussig -Bing anomaly prior to an arterial switch op. Additional muscular VSD which may require closure at the time of sx Other associated anomalies

64. Echo Evaluation of DORV Prior to Single Ventricle Repair Echo complements cardiac catheterization Ventricular function Presence and severity of AV valve regurgitation Size of the branch pulmonary arteries Peripheral pulmonic stenosis if any Severity of pulmonic stenosis (indirect estimate of PA pressures)

65. CARDIAC CATHETERISATION OBJECTIVES: To evaluate Routability of VSD to aorta Branch PA anatomy Pulmonary vascular resistance Coronary artery and aortic arch anatomy.

66. SUB-PULMONIC VSD without PS

67. Tear drop sign SUB-AORTIC VSD WITH PS

68. Management Includes Medical care and surgical management Optimize medical treatment before surgical intervention Surgical P alliative or D efinitive Thorough evaluation important before any plan is made

69. Inadequate pulmonary blood flow – M aintain ductal patency. Prostaglandin E1 (i.e. alprostadil ) until repair. C ongestive heart failure Diuresis , I notropic support Digoxin MEDICAL MANAGEMENT

70. SURGICAL MANAGEMENT When DORV repair is planned – review : PS or PAH Single or Two ventricle repair Relationship of great vessels Location of the VSD and its size Associated lesions

71. Surgical Care - Palliative As medical treatment, this approach helps improve the patient's clinical condition, allowing the baby to gain weight to achieve optimal conditions for definitive surgical repair Palliation Pulmonary artery banding or systemic-to-pulmonary shunt (Modified B-T shunt) Balloon/blade atrial septostomy SURGICAL MANAGEMENT contd …

72. W ith increased PBF and CHF – may first require pulmonary artery banding . NOT RECOMMENDED for infants with ‘Sub-Aortic VSD / Doubly Committed VSD’ “ Primary repair is a better choice ” SURGICAL MANAGEMENT contd … Palliative Procedures

73. SURGICAL MANAGEMENT contd … With pulmonary stenosis – systemic-to-pulmonary shunt, ( modified Blalock- Taussig shunt ), if SpO2< 70%

74. Taussig -Bing type – Balloon/blade atrial septostomy – for better mixing for LA decompression, to relieve PV congestion. Palliative Procedures SURGICAL MANAGEMENT contd …

75. SURGICAL MANAGEMENT contd … Left ventricle to aorta baffle closure ( intra-cardiac rerouting) Simple VSD closure ( subaortic VSD type) Patrick- McGoohan Kawashima (for original Taussig –Bing anomaly) Intraventricular repair with RVOT reconstruction Rastelli REV repair (with Lecompte manuever ) Definitive Procedures

76. Switch operation Arterial switch operation ( Jatene ) Atrial switch operation ( Senning , Mustard) Switch with RVOT reconstruction Switch + Rastelli (or REV) Aortic translocation ( Nikaidoh , double root, truncal switch) Single-ventricle approach Bidirectional Glenn shunt Fontan operation Biventricular repair with DKS Yasui procedure SURGICAL MANAGEMENT contd …

77. Essential Anatomic Determinants of Method of Surgical Repair P osition , size &no. of VSD(s) & its relation to conduction system D istance b/w tricuspid & pulmonary valve Straddling of AV valve Relationship of great arteries Presence of PS/AS Presence of RVOTO/LVOTO & weather fixed or dynamic Coronary artery anatomy

78. IMPORTANCE OF TRICUSPID TO PULMONARY VALVE DISTANCE Dist > diameter of AV – tunnel can be created post. to PV Dist is extremely short – tunnel created to keep PV on LV side Dist < diameter of AV – if tunnel is created post to PV, subaortic stenosis will develop. Tunnel created ant to PV

79. GOALS OF REPAIR Establish connection from LV to aorta To connect RV to PA To close the VSD To correct the associated anomaly SURGICAL MANAGEMENT contd…

80. Principles of surgery Biventricular repair is performed if feasible Adequate LVOT must be created , even if it compromises RVOT RVOT can be reconstructed by infundibulectomy , valvotomy , gusset, or conduit

81. Contraindications to biventricular repair Significant left ventricular hypoplasia Straddling of the atrioventricular valve

82. Ten Commandments Age > 4 yrs Sinus rhythm Normal systemic venous return Normal Right atrial volume Mean pulmonary artery pressure < 15 mm Hg Pulmonary arteriolar resistance < 4 wood units/m 2 Pulmonary artery-aorta ratio >0.75 Left Ventricular ejection fraction >0.60 Competent mitral valve Absence of pulmonary artery distortion

83. Timing of Surgery VSD type One-stage repair as neonate or young infant because of pulmonary over circulation Transposition type One-stage repair as a neonate before LV atrophies Tetralogy type One-stage repair within few months of birth , or T wo stages with initial palliative shunt f/b complete ≥6 months Non-committed type Complete biventricular repair usually deferred beyond 6 months because of complexity of the baffle. Initial palliation with either an aorto -pulmonary shunt or PA band may be needed

84. Timing for Univentricular repair Stable , mildly cyanosed: Direct Fontan operation at 3-4 years of age (Class I) Glenn at 1 yr f/b Fontan at 3-4 year (Class IIa ) Significant cyanosis (SpO2< 70%) Age < 6 month- Systemic to pulmonary artery shunt f/b Glenn at 9 months- 1 year, and Fontan at 3-4 years (Class I). Significant cyanosis (SpO2 <70%) Age > 6 months- BD Glenn followed by Fontan at 3-4 years (Class I).

85. Pulmonary artery assessment In patients with PS, degree of PA hypoplasia to be assessed; McGoon ratio :- ratio of sum of immediate prebranching RPA & LPA diameter to descending Ao diameter just above the diaphragm. Normal = 2 – 2.5 Good Fontan candidate >1.8 Nakata Index: ratio of cross- s ectional area of RPA & LPA to BSA. Normal= 330±30 mm 2 /BSA Good Fontan candidate >250 Good Rastelli candidate>200 Patients < 200 – shunt surgery is better

86. Size of ventricles and AV valves are adequate Yes No VSD to aortic baffle can be created without LVOT obstruction SV or 1½ Repair Glenn/ Fontan Yes No Any obstruction to PV or RVOT VSD to PV baffle can be created without obstruction Yes No DKS with RV-PA Yasul proceedure SV Repair Glenn/ Fontan Yes No Simple IVR IVR with RVOT reconstruction Simple VSD closure Patrick- MacGoohan Kawashima Rastelli REV ( Lecompte ) Any obstruction in Neo PV or RVOT Switch Arterial switch Atrial switch ( Senning /Mustard) Yes No Switch with RVOT reconstruction Switch + Rastelli Switch + REV Nikaidoh (aortic translocation) Double root translocation Truncal switch ( Yamagishi ) DORV Surgical approach Repair of DORV with subaortic VSD Intraventricular tunnel. If the VSD is smaller than the aorta, VSD is enlarged. Mortality rate is <5% (subaortic VSD) REV Proceedure Modified REV procedure: Pulmonary root translocation technique. A, Pulmonary root harvesting. The ascending aorta transected above the sinus–tubular conjunction. B, Lecompte maneuver is done. Restoration of RV–PA continuity. A single-valved bovine jugular vein patch to repair RVOT, enlarge the stenotic main pulmonary artery, and restore the competence of the neo-pulmonary valve. Repair of DORV with subaortic VSD and PS Similar to DORV and subaortic VSD without PS. During repair PS may require : - Pulmonary valvotomy - Infundibular resection - Patch enlargement of RVOT Yasui Proceedure Single ventricle repair Mustard/Senning procedure Nikaidoh procedure

87. Surgical approach to DORV

88. Repair of DORV with subaortic VSD I ntraventricular tunnel. If the VSD is smaller than the aorta, VSD is enlarged. Mortality rate is <5% ( subaortic VSD)

89. Repair of DORV with subaortic VSD and PS Similar to DORV and subaortic VSD without PS. During repair PS may require : - Pulmonary valvotomy - Infundibular resection - Patch enlargement of RVOT

90. REV Proceedure Modified REV procedure: Pulmonary root translocation technique. A , Pulmonary root harvesting. The ascending aorta transected above the sinus–tubular conjunction. B , Lecompte maneuver is done. Restoration of RV–PA continuity. A single- valved bovine jugular vein patch to repair RVOT, enlarge the stenotic main pulmonary artery, and restore the competence of the neo-pulmonary valve.

91. Nikaidoh procedure

92. Single ventricle repair

93. Mustard/ Senning procedure

94. Yasui Proceedure

95. Taussig -Bing Anomaly: - 3 possible approaches. Early surgery is recommended because of rapid development of PVOD. 1. An Intraventricular tunnel between the VSD and PA with the arterial switch operation. Preferred surgical method Mortality 10-15%. Anatomic repair of DORV with subpulmonary VSD

96. Anatomic repair of DORV with subpulmonary VSD

97. The second method – Consists of construction of a long intraventricular tunnel to establish continuity between the LV and the aorta and between the RV and PA.

98. Copyright ©1999 The American Association for Thoracic Surgery

99. The third method C losure of the VSD with baffling of the LVOT to the pulmonary artery with a subsequent atrial baffle ( eg , Senning procedure, Mustard procedure). This method is associated with high operative and late mortality rates.

100. Because coarctation of the aorta is commonly observed in this situation, patients may have to undergo coarctation repair with a pulmonary artery band The subsequent procedure is a single stage complete repair with VSD enlargement if restrictive, repair of the VSD to direct the left ventricular blood to the pulmonary artery, followed by an arterial switch procedure. Aortic arch obstruction - repaired at the same time under hypothermic circulatory arrest

101. Repair of DORV with doubly committed VSD Surgical correction - similar to that described for double outlet right ventricle with subaortic VSD. The VSD, which is typically large, usually does not create difficulty in channeling left ventricular blood to the aorta with an intraventricular tunnel. Concurrent pulmonary stenosis or obstruction of the right ventricular outflow tract due to the tunnel may necessitate the creation of a right ventricle outflow patch or even a right ventricle–to–pulmonary artery conduit.

102. .

103. Repair of DORV with noncommitted VSD Most difficult to correct. High-risk procedure that often involves univentricular repair. However, biventricular repair of double outlet right ventricle with noncommitted VSD has been described and done The major feature of this anomaly is a persistent subaortic conus and a double infundibulum.

104. Repair of DORV with noncommitted VSD The subaortic conus is in excess to essentially normal right ventricular structures. Represents malposition of the aorta, with a normally positioned pulmonary artery and with the great vessels usually side by side. The VSD, usually perimembranous , often has inlet and/or trabecular extension and can be restrictive.

105. POTENTIAL DANGER AREAS DURING SURGICAL CORRECTION

106. MAJOR CONCERNS EARLY AFTER REPAIR PROGRESSIVE VENTRICULAR DYSFUNCTION Residual VSD AV valve insufficiency Prolonged circulatory arrest at intracardiac repair.