Case Report
Left Isomerism of the Atrial Appendages With Sinus Venosus Defect and Anomalous Systemic Venous Drainage
World Journal for Pediatric and Congenital Heart Surgery 2016, Vol. 7(5) 661-664 ª The Author(s) 2016 Reprints and permission: sagepub.com/journalsPermissions.nav DOI: 10.1177/2150135115610283 pch.sagepub.com
Sachin Talwar, MCh1, Pradeep Ramakrishnan, MS1, Robert H. Anderson, MD, FRCPath2, Shiv Kumary Choudhary, MCh1, Neeti Makhija, MD1, Sanjiv Kumar, MD1, and Balram Airan, MCh1
Abstract We present a case with left isomerism, interruption of the inferior caval vein, anomalous systemic venous drainage with partially anomalous pulmonary venous drainage, and a sinus venosus type of atrial septal defect in the absence of a right superior caval vein. This report is of interest because of a rare combination of these anomalies, which was accurately diagnosed and successfully repaired. Keywords left isomerism, atrial septal defect, anomalies of systemic veins, anomalies of pulmonary veins Submitted June 08, 2015; Accepted September 03, 2015.
Introduction It is now well recognized that patients with so-called ‘‘heterotaxy’’ can be segregated on the basis of isomerism of the atrial appendages.1 In those with left isomerism, because both appendages are of left morphology, it could be argued that connections of the pulmonary veins to either the right-sided or the left-sided atrium are anatomically ‘‘normal,’’ whereas the systemic veins will always be connected in an anatomically abnormal fashion. In terms of hemodynamics, however, it is necessary to be aware of the precise connections of each vein. This is exemplified by our recent experience in which we encountered a patient with left isomerism in whom all systemic veins were connected to the left-sided atrium, whereas one of the right-sided pulmonary veins was anomalously connected to the left-sided atrium, in combination with a sinus venosus interatrial communication.
Case Report A one-year-old female child presented with tachypnea, increased precordial activity, and frequent infections of the lower respiratory tract since six months of age. Pertinent findings on physical examination were cyanosis and an ejection systolic murmur in the left upper parasternal area. Chest radiography revealed cardiomegaly, with features of increased pulmonary blood flow. The electrocardiogram showed a heart rate of 60/minute, an ectopic atrial rhythm suggestive of the absence of the sinus
node, prolongation of the PR interval, a superior P wave axis, right ventricular hypertrophy, and right bundle branch block. Cross-sectional transthoracic echocardiograms suggested left isomerism with a left-sided heart. The inferior caval vein was not seen in its normal position, and the right-sided superior caval vein was not identified. The pulmonary veins were noted to drain with some degree of symmetry, with the right upper pulmonary vein identified as draining directly into the rightsided atrium, whereas the other right-sided and the left-sided pulmonary veins were noted to drain into the left-sided atrium. A large interatrial communication was present, permitting bidirectional flow, and a small patent arterial duct, 3 mm in diameter, was also identified. Computed tomographic angiography (Figure 1) confirmed the presence of left isomerism with a left-sided heart and showed mixed atrioventricular connections with right-handed ventricular topology and concordant ventriculoarterial connections. The arterial trunks were spiraling and normally related to dilated pulmonary arteries. A left-sided superior caval vein was demonstrated, which
1 Cardiothoracic Centre, All India Institute of Medical Sciences, New Delhi, India 2 Institute of Genetic Medicine, Newcastle University, Newcastle-upon-Tyne, England
Corresponding Author: Sachin Talwar, Department of Cardiothoracic and Vascular Surgery, All India Institute of Medical Sciences, New Delhi 110029, India. Email: [email protected]
Downloaded from pch.sagepub.com at University of Otago Library on November 11, 2016
662
World Journal for Pediatric and Congenital Heart Surgery 7(5)
Figure 1. Computed tomographic angiography images that depict the anatomy. A, Coronal multiplanar reformatted image of the chest showing the LSVC draining into the left-sided atrium and separate drainage of HV into the left-sided atrium. B, Axial CECT image, mediastinal window, showing the right pulmonary vein (single arrow) draining into the RA and the left pulmonary vein (double arrow) draining into the LA. C, Coronal CT image, lung window, showing T and bilateral eparterial bronchus (left isomerism). D, Axial CECT image, mediastinal window, showing bilateral morphologically left atrial appendages (left isomerism). CECT, contrast-enhanced CT; CT, computed tomography; HV, hepatic vein; L, appendage of LA; LA, left-sided atrium; LSVC, left-sided superior caval vein; R, appendage of RA; RA, right-sided atrium; T, trachea.
opened into the left-sided atrium between its appendage and the openings of the left-sided pulmonary veins. The caval vein also drained a left-sided inferior caval vein, which was interrupted, continuing through left-sided azygos venous system. The hepatic veins drained directly into the left-sided atrium, with only the right upper and middle pulmonary veins draining into the right-sided atrium. There was no evidence of a right-sided superior caval vein. There were no extracardiac anomalies. The patient was referred for complete surgical repair. The surgical approach was through a midline sternotomy. A patch of pericardium was harvested and fixed in 0.625% glutaraldehyde for 20 minutes. Cardiopulmonary bypass was established by cannulation of the aorta and the left-sided superior caval vein, with core cooling to 28 C. Another small cannula was placed low in the left-sided atrium adjacent to the site of entry of the hepatic veins to drain the hepatic venous return. After applying the aortic cross clamp and delivering cardioplegia into the aortic root, we opened the right-sided atrium. This permitted us to confirm the connection of the left-sided superior caval vein to the roof of the left-sided atrium and showed that two of the right-sided pulmonary veins drained into the right-sided atrium. The hepatic veins drained into the left-sided atrium in close proximity to the line
of attachment of the interatrial septum. We noted that the upper rim of the oval fossa, which was itself deficient because of the deficiency of the flap valve, separated the oval fossa defect from a second defect in the roof of the atrial chamber. Complete repair was achieved by rerouting the right-sided pulmonary veins into the left-sided atrium and the left-sided superior caval vein, along with the hepatic veins, into the right-sided atrium. So as to achieve this using a single pericardial patch, it was necessary to excise the superior rim of the oval fossa and enlarge the interatrial communication. This made it possible to secure the patch in front of the pulmonary veins but behind the hepatic veins and the orifice of the leftsided superior caval vein, with the suture line transitioning at various points to achieve the desired anatomical configuration (Figure 2). The remainder of the operation was completed in a routine fashion. The aorta was cross clamped for 36 minutes, whereas 74 minutes were required for cardiopulmonary bypass. Intraoperative transesophageal echocardiography excluded any residual shunting and showed the newly constructed systemic and pulmonary venous pathways to be unobstructed. At three months of follow-up, the patient is asymptomatic, with a systemic saturation of 100% and no residual defects on echocardiography.
Downloaded from pch.sagepub.com at University of Otago Library on November 11, 2016
Talwar et al
663
Figure 2. Line drawing showing (A) surgical anatomy and (B) method of repair. For details see text. *Opening of LSVC into the roof of the leftsided atrium. H indicates left-sided azygos venous system; HV, hepatic vein; IVC, inferior caval vein; LSVC, left superior caval vein; P, pericardial patch; PV, pulmonary vein.
Discussion Anomalous venoatrial connections are now well established as one of the primary features of hearts with isomeric atrial appendages.1 Leonardo da Vinci allegedly illustrated such isomeric appendages in his illustrations of the heart.2 It was Ivemark, however, who first pointed to the symmetry to be found in so-called heterotaxy, although he then concentrated on the splenic anomalies, which are also recognized to be features of these syndromes.3 It is now known that interruption of the inferior caval vein, along with anomalous formation of the sinus node, is a feature of left as opposed to right isomerism. Bilateral superior caval veins are also found in around twothirds of such patients, and if one caval vein is lacking, it is usually the left-sided one. When present, furthermore, the leftsided superior caval vein often drains into the coronary sinus. Drainage directly into the atrial roof is unusual, which is reported in less than one-sixth of the cases.1 In our patient, not only did the left-sided caval vein drain directly into the roof of the leftsided atrium, but it did so in the absence of a right-sided superior caval vein. On opening the atrial chambers, however, we found a second superior interatrial communication, outside the confines of the oval fossa, which had obvious muscular rims, with a large defect within it due to the deficiency of its flap valve. Azygos extension of an interrupted inferior caval vein is encountered in about three-quarters of patients with left isomerism, with the vein continuing in posterior location to either the right or the left side of the vertebral column.4,5 In our patient, it was left sided. The hepatic veins also drained into the left-sided atrium. The right upper and middle pulmonary veins
drained into the right-sided atrium, whereas the right lower and left-sided pulmonary veins joined the left-sided atrium. Symmetrical drainage is to be anticipated in hearts with isomeric left atrial appendages, albeit not always present.1 An unexpected feature of our patient was the presence of a second interatrial defect in the roof of the atrial chambers. We interpret the defect as representing a sinus venosus type of communication, although there was an absence of the right superior caval vein. The morphology was comparable to one of our previous cases,6 although that patient had usual atrial arrangement. It is now well recognized that the sinus venosus defect is the consequence of anomalous connection of a pulmonary vein to a systemic vein that has retained its left atrial connection.7 In our patient, it was the anomalously connected right lower pulmonary vein that produced the veno-venous bridge. The defects are differentiated from the more usual defects within the oval fossa by recognition of the integrity of the margins of the fossa. There is a paucity of data in the literature on successful surgical correction of the so-called totally anomalous systemic venous connection. To the best of our knowledge, only 15 patients have thus far been described to have undergone successful surgical repair.8-14 It is arguable as to whether our patient should be considered to have totally anomalous systemic venous drainage, since all of the systemic veins, of necessity, will be connected in an anatomically anomalous fashion when both appendages are of left morphology. The arrangement in our patient is akin to totally anomalous systemic venous drainage as seen in the setting of usual atrial arrangement, since all of the veins were connected to the left-sided atrium. The rightsided atrium, nonetheless, also had an appendage of left
Downloaded from pch.sagepub.com at University of Otago Library on November 11, 2016
664
World Journal for Pediatric and Congenital Heart Surgery 7(5)
morphology. This explains why many patients with left isomerism have symmetrical drainage of the pulmonary veins, although in our patient one of the right-sided veins connected to the left-sided atrium. We are unaware of any previous description of this variant. Our findings emphasize the necessity of providing precise descriptions of all the venoatrial connections in patients with isomeric atrial appendages. Only in this way will we dispel the notion of ‘‘ambiguity’’ produced when such patients are considered to exhibit heterotaxy. Such precise description of the venoatrial connections is then of great importance for the cardiac surgeon. This is because, while performing surgery in these patients, the strategies for venous cannulation are of paramount importance. Both the superior and inferior caval veins need to be cannulated for adequate venous return and to produce the optimal bloodless field. The hepatic venous drainage is usually managed by the placement of the cannula into the inferior caval vein. In the setting of left isomerism, however, as in our patient, the inferior caval vein must be anticipated to be interrupted. In this setting, the hepatic veins drained directly into the atrial chambers. We chose to cannulate the left-sided superior caval vein using a large angled cannula, taking care to place the cannula in such a way that we would not obstruct the opening of the left-sided azygos vein into the left-sided superior caval vein. We used a small angled cannula to manage the hepatic venous return. The strategies for cannulation have been emphasized by Zhang et al.14 When the caval vein is not interrupted, of course, then it is possible to use conventional cardiopulmonary bypass. When the vessel is interrupted, then it is single cannulation of the superior caval vein, irrespective of its sidedness, which permits the use of conventional cardiopulmonary bypass. The safe establishment of cardiopulmonary bypass is a prerequisite to accurate assessment of the underlying anatomy, which itself is essential if the optimal approach to intracardiac rerouting is to be achieved. At least onethird of patients with left isomerism are known to be amenable to biventricular repair, with this proportion likely to increase when greater attention is directed to recognition of the appropriate isomeric features of patient with so-called heterotaxy. Those patients referred for surgical intervention have had better short- and longterm outcomes when compared to those having no intervention.2 Patients with suspected isomerism, of course, should always be evaluated for extracardiac malformations such as polysplenia or extrahepatic biliary atresia and managed appropriately. Accurate diagnosis of all associated features should be expected with modern day diagnostic facilities, particularly the use of computed tomographic angiography. As with the venoatrial connections, description of the various features removes any suspicion of ambiguity in the workup of the patients. Acknowledgments The authors thank Dr Amolkumar Bhoje for drawing Figure 2.
Declaration of Conflicting Interests The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding The author(s) received no financial support for the research, authorship, and/or publication of this article.
References 1. Uemura H, Ho SY, Devine WA, Kilpatrick LL, Anderson RH. Atrial appendages and venoatrial connections in hearts from patients with visceral heterotaxy. Ann Thorac Surg. 1995;60(3): 561-569. 2. Kouchokous NT, Blackstone EH, Hanley FH, Kirklin JK. Atrial isomerism. In: Kouchokous NT, Blackstone EH, Hanley FH, Kirklin JK, eds. Kirklin/Barret-Boyes Cardiac Surgery. 4th ed. Philadelphia, PA: Elsevier Saunders; 2013:2040-2054. 3. Ivemark BI. Implications of agenesis of spleen on pathogenesis of conotruncus anomalies in childhood; analysis of heart malformations in splenic agenesis syndrome, with fourteen new cases. Acta Paediatr. 1955;44(suppl 104): 7-110. 4. Kandpal H, Sharma R, Gamangatti S, Srivastava DN, Vashisht S. Imaging the inferior vena cava: a road less traveled. Radiographics. 2008;28(3): 669-689. 5. Haswell DM, Berrigan TJ Jr. Anomalous inferior vena cava with accessory hemiazygos continuation. Radiology. 1976;119(1): 51-54. 6. Talwar S, Upadhyay M, Choudhary SK, Kothari SS, Anderson RH, Airan B. Interatrial communications with unusual caval venous anomalies. World J Pediatr Congenit Heart Surg. 2010; 1(3): 400-403. 7. Oruganti SS, Jariwala P, Taggarse AK, Mishra RC. Unusual venacaval anomalies in a patient with atrial septal defect. Asian Cardiovasc Thorac Ann. 2008;16(6): 492-494. 8. Awasthy N, Radhakrishnan S, Kaushal S, Sharma R. Total anomalous systemic venous drainage to the left atrium: an entity reviewed and investigated. Ann Pediatr Cardiol. 2014;7(2): 98-102. 9. Krayenbuhl CU, Lincoln JC. Total anomalous systemic venous connection, common atrium, and partial atrio-ventricular canal. A case report of successful surgical correction. J Thorac Cardiovasc Surg. 1977;73(5): 686-689. 10. Danielson GK, McMullan MH, Kinsley RH, DuShane JW. Successful repair of complete atrioventricular canal associated with dextroversion, common atrium, and total anomalous systemic venous return. J Thorac Cardiovasc Surg. 1973;66(5): 817-822. 11. Roberts KD, Edwards JM, Astley R. Surgical correction of total anomalous systemic venous drainage. J Thorac Cardiovasc Surg. 1972;64(5): 803-810. 12. Gueron M, Hirsh M, Borman J. Total anomalous systemic venous drainage into the left atrium. Report of a case of successful surgical correction. J Thorac Cardiovasc Surg. 1969; 58(4): 570-574. 13. Miller GA, Ongley PA, Rastelli GC, Kirklin JW. Surgical correction of total anomalous systemic venous connection: report of case. Mayo Clin Proc. 1965;40: 532-538. 14. Zhang ZW, Duan QJ, Gao Z, Ru W, Ying LY. Total anomalous systemic venous drainage to the left atrium. Ann Thorac Surg. 2009;87(5): 1599.
Downloaded from pch.sagepub.com at University of Otago Library on November 11, 2016
Left Isomerism of the Atrial Appendages With Sinus Venosus Defect and Anomalous Systemic Venous Drainage
World Journal for Pediatric and Congenital Heart Surgery 2016, Vol. 7(5) 661-664 ª The Author(s) 2016 Reprints and permission: sagepub.com/journalsPermissions.nav DOI: 10.1177/2150135115610283 pch.sagepub.com
Sachin Talwar, MCh1, Pradeep Ramakrishnan, MS1, Robert H. Anderson, MD, FRCPath2, Shiv Kumary Choudhary, MCh1, Neeti Makhija, MD1, Sanjiv Kumar, MD1, and Balram Airan, MCh1
Abstract We present a case with left isomerism, interruption of the inferior caval vein, anomalous systemic venous drainage with partially anomalous pulmonary venous drainage, and a sinus venosus type of atrial septal defect in the absence of a right superior caval vein. This report is of interest because of a rare combination of these anomalies, which was accurately diagnosed and successfully repaired. Keywords left isomerism, atrial septal defect, anomalies of systemic veins, anomalies of pulmonary veins Submitted June 08, 2015; Accepted September 03, 2015.
Introduction It is now well recognized that patients with so-called ‘‘heterotaxy’’ can be segregated on the basis of isomerism of the atrial appendages.1 In those with left isomerism, because both appendages are of left morphology, it could be argued that connections of the pulmonary veins to either the right-sided or the left-sided atrium are anatomically ‘‘normal,’’ whereas the systemic veins will always be connected in an anatomically abnormal fashion. In terms of hemodynamics, however, it is necessary to be aware of the precise connections of each vein. This is exemplified by our recent experience in which we encountered a patient with left isomerism in whom all systemic veins were connected to the left-sided atrium, whereas one of the right-sided pulmonary veins was anomalously connected to the left-sided atrium, in combination with a sinus venosus interatrial communication.
Case Report A one-year-old female child presented with tachypnea, increased precordial activity, and frequent infections of the lower respiratory tract since six months of age. Pertinent findings on physical examination were cyanosis and an ejection systolic murmur in the left upper parasternal area. Chest radiography revealed cardiomegaly, with features of increased pulmonary blood flow. The electrocardiogram showed a heart rate of 60/minute, an ectopic atrial rhythm suggestive of the absence of the sinus
node, prolongation of the PR interval, a superior P wave axis, right ventricular hypertrophy, and right bundle branch block. Cross-sectional transthoracic echocardiograms suggested left isomerism with a left-sided heart. The inferior caval vein was not seen in its normal position, and the right-sided superior caval vein was not identified. The pulmonary veins were noted to drain with some degree of symmetry, with the right upper pulmonary vein identified as draining directly into the rightsided atrium, whereas the other right-sided and the left-sided pulmonary veins were noted to drain into the left-sided atrium. A large interatrial communication was present, permitting bidirectional flow, and a small patent arterial duct, 3 mm in diameter, was also identified. Computed tomographic angiography (Figure 1) confirmed the presence of left isomerism with a left-sided heart and showed mixed atrioventricular connections with right-handed ventricular topology and concordant ventriculoarterial connections. The arterial trunks were spiraling and normally related to dilated pulmonary arteries. A left-sided superior caval vein was demonstrated, which
1 Cardiothoracic Centre, All India Institute of Medical Sciences, New Delhi, India 2 Institute of Genetic Medicine, Newcastle University, Newcastle-upon-Tyne, England
Corresponding Author: Sachin Talwar, Department of Cardiothoracic and Vascular Surgery, All India Institute of Medical Sciences, New Delhi 110029, India. Email: [email protected]
Downloaded from pch.sagepub.com at University of Otago Library on November 11, 2016
662
World Journal for Pediatric and Congenital Heart Surgery 7(5)
Figure 1. Computed tomographic angiography images that depict the anatomy. A, Coronal multiplanar reformatted image of the chest showing the LSVC draining into the left-sided atrium and separate drainage of HV into the left-sided atrium. B, Axial CECT image, mediastinal window, showing the right pulmonary vein (single arrow) draining into the RA and the left pulmonary vein (double arrow) draining into the LA. C, Coronal CT image, lung window, showing T and bilateral eparterial bronchus (left isomerism). D, Axial CECT image, mediastinal window, showing bilateral morphologically left atrial appendages (left isomerism). CECT, contrast-enhanced CT; CT, computed tomography; HV, hepatic vein; L, appendage of LA; LA, left-sided atrium; LSVC, left-sided superior caval vein; R, appendage of RA; RA, right-sided atrium; T, trachea.
opened into the left-sided atrium between its appendage and the openings of the left-sided pulmonary veins. The caval vein also drained a left-sided inferior caval vein, which was interrupted, continuing through left-sided azygos venous system. The hepatic veins drained directly into the left-sided atrium, with only the right upper and middle pulmonary veins draining into the right-sided atrium. There was no evidence of a right-sided superior caval vein. There were no extracardiac anomalies. The patient was referred for complete surgical repair. The surgical approach was through a midline sternotomy. A patch of pericardium was harvested and fixed in 0.625% glutaraldehyde for 20 minutes. Cardiopulmonary bypass was established by cannulation of the aorta and the left-sided superior caval vein, with core cooling to 28 C. Another small cannula was placed low in the left-sided atrium adjacent to the site of entry of the hepatic veins to drain the hepatic venous return. After applying the aortic cross clamp and delivering cardioplegia into the aortic root, we opened the right-sided atrium. This permitted us to confirm the connection of the left-sided superior caval vein to the roof of the left-sided atrium and showed that two of the right-sided pulmonary veins drained into the right-sided atrium. The hepatic veins drained into the left-sided atrium in close proximity to the line
of attachment of the interatrial septum. We noted that the upper rim of the oval fossa, which was itself deficient because of the deficiency of the flap valve, separated the oval fossa defect from a second defect in the roof of the atrial chamber. Complete repair was achieved by rerouting the right-sided pulmonary veins into the left-sided atrium and the left-sided superior caval vein, along with the hepatic veins, into the right-sided atrium. So as to achieve this using a single pericardial patch, it was necessary to excise the superior rim of the oval fossa and enlarge the interatrial communication. This made it possible to secure the patch in front of the pulmonary veins but behind the hepatic veins and the orifice of the leftsided superior caval vein, with the suture line transitioning at various points to achieve the desired anatomical configuration (Figure 2). The remainder of the operation was completed in a routine fashion. The aorta was cross clamped for 36 minutes, whereas 74 minutes were required for cardiopulmonary bypass. Intraoperative transesophageal echocardiography excluded any residual shunting and showed the newly constructed systemic and pulmonary venous pathways to be unobstructed. At three months of follow-up, the patient is asymptomatic, with a systemic saturation of 100% and no residual defects on echocardiography.
Downloaded from pch.sagepub.com at University of Otago Library on November 11, 2016
Talwar et al
663
Figure 2. Line drawing showing (A) surgical anatomy and (B) method of repair. For details see text. *Opening of LSVC into the roof of the leftsided atrium. H indicates left-sided azygos venous system; HV, hepatic vein; IVC, inferior caval vein; LSVC, left superior caval vein; P, pericardial patch; PV, pulmonary vein.
Discussion Anomalous venoatrial connections are now well established as one of the primary features of hearts with isomeric atrial appendages.1 Leonardo da Vinci allegedly illustrated such isomeric appendages in his illustrations of the heart.2 It was Ivemark, however, who first pointed to the symmetry to be found in so-called heterotaxy, although he then concentrated on the splenic anomalies, which are also recognized to be features of these syndromes.3 It is now known that interruption of the inferior caval vein, along with anomalous formation of the sinus node, is a feature of left as opposed to right isomerism. Bilateral superior caval veins are also found in around twothirds of such patients, and if one caval vein is lacking, it is usually the left-sided one. When present, furthermore, the leftsided superior caval vein often drains into the coronary sinus. Drainage directly into the atrial roof is unusual, which is reported in less than one-sixth of the cases.1 In our patient, not only did the left-sided caval vein drain directly into the roof of the leftsided atrium, but it did so in the absence of a right-sided superior caval vein. On opening the atrial chambers, however, we found a second superior interatrial communication, outside the confines of the oval fossa, which had obvious muscular rims, with a large defect within it due to the deficiency of its flap valve. Azygos extension of an interrupted inferior caval vein is encountered in about three-quarters of patients with left isomerism, with the vein continuing in posterior location to either the right or the left side of the vertebral column.4,5 In our patient, it was left sided. The hepatic veins also drained into the left-sided atrium. The right upper and middle pulmonary veins
drained into the right-sided atrium, whereas the right lower and left-sided pulmonary veins joined the left-sided atrium. Symmetrical drainage is to be anticipated in hearts with isomeric left atrial appendages, albeit not always present.1 An unexpected feature of our patient was the presence of a second interatrial defect in the roof of the atrial chambers. We interpret the defect as representing a sinus venosus type of communication, although there was an absence of the right superior caval vein. The morphology was comparable to one of our previous cases,6 although that patient had usual atrial arrangement. It is now well recognized that the sinus venosus defect is the consequence of anomalous connection of a pulmonary vein to a systemic vein that has retained its left atrial connection.7 In our patient, it was the anomalously connected right lower pulmonary vein that produced the veno-venous bridge. The defects are differentiated from the more usual defects within the oval fossa by recognition of the integrity of the margins of the fossa. There is a paucity of data in the literature on successful surgical correction of the so-called totally anomalous systemic venous connection. To the best of our knowledge, only 15 patients have thus far been described to have undergone successful surgical repair.8-14 It is arguable as to whether our patient should be considered to have totally anomalous systemic venous drainage, since all of the systemic veins, of necessity, will be connected in an anatomically anomalous fashion when both appendages are of left morphology. The arrangement in our patient is akin to totally anomalous systemic venous drainage as seen in the setting of usual atrial arrangement, since all of the veins were connected to the left-sided atrium. The rightsided atrium, nonetheless, also had an appendage of left
Downloaded from pch.sagepub.com at University of Otago Library on November 11, 2016
664
World Journal for Pediatric and Congenital Heart Surgery 7(5)
morphology. This explains why many patients with left isomerism have symmetrical drainage of the pulmonary veins, although in our patient one of the right-sided veins connected to the left-sided atrium. We are unaware of any previous description of this variant. Our findings emphasize the necessity of providing precise descriptions of all the venoatrial connections in patients with isomeric atrial appendages. Only in this way will we dispel the notion of ‘‘ambiguity’’ produced when such patients are considered to exhibit heterotaxy. Such precise description of the venoatrial connections is then of great importance for the cardiac surgeon. This is because, while performing surgery in these patients, the strategies for venous cannulation are of paramount importance. Both the superior and inferior caval veins need to be cannulated for adequate venous return and to produce the optimal bloodless field. The hepatic venous drainage is usually managed by the placement of the cannula into the inferior caval vein. In the setting of left isomerism, however, as in our patient, the inferior caval vein must be anticipated to be interrupted. In this setting, the hepatic veins drained directly into the atrial chambers. We chose to cannulate the left-sided superior caval vein using a large angled cannula, taking care to place the cannula in such a way that we would not obstruct the opening of the left-sided azygos vein into the left-sided superior caval vein. We used a small angled cannula to manage the hepatic venous return. The strategies for cannulation have been emphasized by Zhang et al.14 When the caval vein is not interrupted, of course, then it is possible to use conventional cardiopulmonary bypass. When the vessel is interrupted, then it is single cannulation of the superior caval vein, irrespective of its sidedness, which permits the use of conventional cardiopulmonary bypass. The safe establishment of cardiopulmonary bypass is a prerequisite to accurate assessment of the underlying anatomy, which itself is essential if the optimal approach to intracardiac rerouting is to be achieved. At least onethird of patients with left isomerism are known to be amenable to biventricular repair, with this proportion likely to increase when greater attention is directed to recognition of the appropriate isomeric features of patient with so-called heterotaxy. Those patients referred for surgical intervention have had better short- and longterm outcomes when compared to those having no intervention.2 Patients with suspected isomerism, of course, should always be evaluated for extracardiac malformations such as polysplenia or extrahepatic biliary atresia and managed appropriately. Accurate diagnosis of all associated features should be expected with modern day diagnostic facilities, particularly the use of computed tomographic angiography. As with the venoatrial connections, description of the various features removes any suspicion of ambiguity in the workup of the patients. Acknowledgments The authors thank Dr Amolkumar Bhoje for drawing Figure 2.
Declaration of Conflicting Interests The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding The author(s) received no financial support for the research, authorship, and/or publication of this article.
References 1. Uemura H, Ho SY, Devine WA, Kilpatrick LL, Anderson RH. Atrial appendages and venoatrial connections in hearts from patients with visceral heterotaxy. Ann Thorac Surg. 1995;60(3): 561-569. 2. Kouchokous NT, Blackstone EH, Hanley FH, Kirklin JK. Atrial isomerism. In: Kouchokous NT, Blackstone EH, Hanley FH, Kirklin JK, eds. Kirklin/Barret-Boyes Cardiac Surgery. 4th ed. Philadelphia, PA: Elsevier Saunders; 2013:2040-2054. 3. Ivemark BI. Implications of agenesis of spleen on pathogenesis of conotruncus anomalies in childhood; analysis of heart malformations in splenic agenesis syndrome, with fourteen new cases. Acta Paediatr. 1955;44(suppl 104): 7-110. 4. Kandpal H, Sharma R, Gamangatti S, Srivastava DN, Vashisht S. Imaging the inferior vena cava: a road less traveled. Radiographics. 2008;28(3): 669-689. 5. Haswell DM, Berrigan TJ Jr. Anomalous inferior vena cava with accessory hemiazygos continuation. Radiology. 1976;119(1): 51-54. 6. Talwar S, Upadhyay M, Choudhary SK, Kothari SS, Anderson RH, Airan B. Interatrial communications with unusual caval venous anomalies. World J Pediatr Congenit Heart Surg. 2010; 1(3): 400-403. 7. Oruganti SS, Jariwala P, Taggarse AK, Mishra RC. Unusual venacaval anomalies in a patient with atrial septal defect. Asian Cardiovasc Thorac Ann. 2008;16(6): 492-494. 8. Awasthy N, Radhakrishnan S, Kaushal S, Sharma R. Total anomalous systemic venous drainage to the left atrium: an entity reviewed and investigated. Ann Pediatr Cardiol. 2014;7(2): 98-102. 9. Krayenbuhl CU, Lincoln JC. Total anomalous systemic venous connection, common atrium, and partial atrio-ventricular canal. A case report of successful surgical correction. J Thorac Cardiovasc Surg. 1977;73(5): 686-689. 10. Danielson GK, McMullan MH, Kinsley RH, DuShane JW. Successful repair of complete atrioventricular canal associated with dextroversion, common atrium, and total anomalous systemic venous return. J Thorac Cardiovasc Surg. 1973;66(5): 817-822. 11. Roberts KD, Edwards JM, Astley R. Surgical correction of total anomalous systemic venous drainage. J Thorac Cardiovasc Surg. 1972;64(5): 803-810. 12. Gueron M, Hirsh M, Borman J. Total anomalous systemic venous drainage into the left atrium. Report of a case of successful surgical correction. J Thorac Cardiovasc Surg. 1969; 58(4): 570-574. 13. Miller GA, Ongley PA, Rastelli GC, Kirklin JW. Surgical correction of total anomalous systemic venous connection: report of case. Mayo Clin Proc. 1965;40: 532-538. 14. Zhang ZW, Duan QJ, Gao Z, Ru W, Ying LY. Total anomalous systemic venous drainage to the left atrium. Ann Thorac Surg. 2009;87(5): 1599.
Downloaded from pch.sagepub.com at University of Otago Library on November 11, 2016
