Case Study
Hemitruncus, septal defect, and anomalous coronary artery from pulmonary artery
Asian Cardiovascular & Thoracic Annals 21(3) 338–341 ß The Author(s) 2012 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/0218492312454018 aan.sagepub.com
Sachin Talwar, Palleti Rajashekar, Saurabh Kumar Gupta, Gurpreet Singh Gulati, Shiv Kumar Choudhary and Balram Airan
Abstract An 8-month-old boy with aortic origin of the right pulmonary artery, ventricular septal defect, and anomalous origin of the left main coronary artery from the right pulmonary artery, underwent uneventful single-stage surgical correction. The rarity and technical aspects of managing this condition are discussed.
Keywords Coronary vessel anomalies, heart defects, congenital, heart septal defects, ventricular, pulmonary artery
Introduction Anomalous origin of a branch pulmonary artery (PA) from the aorta (hemitruncus) is a rare congenital cardiac anomaly in which of one of the branch PA arises from the ascending aorta and the other arises from the right ventricular outflow tract in the presence of 2 semilunar valves.1 It is often associated with other intracardiac defects.2 However, the combination of hemitruncus, ventricular septal defect (VSD) and anomalous origin of the left main coronary artery (LMCA) from the right PA is extremely unusual.
Case report An 8-month-old boy, weighing 4.5 kg, presented with tachypnea, sweating during feeding, poor weight gain, and recurrent lower respiratory tract infections since birth. On examination, he appeared poorly nourished, his pulse rate was 102 beats per minute, and all peripheral pulses were palpable and synchronous. The apex beat was in the 6th intercostal space lateral to the midclavicular line. The 1st heart sound was normal, the 2nd heart sound was loud, and a grade 3/6 pansystolic murmur was heard at the left 3rd intercostal space. Chest radiography revealed left ventricular enlargement. An electrocardiogram also showed left
ventricular enlargement with no evidence of myocardial ischemia. Transthoracic echocardiography demonstrated a large perimembranous VSD with a leftto-right shunt, a patent foramen ovale, and severe PA hypertension. The right PA was seen to be dilated and arising from the aorta. There was a suspicion of the LMCA arising from the right PA. Computed tomography angiography revealed a large perimembranous VSD with the right PA (1 cm) arising from the posterior aspect of the ascending aorta, while the left PA (0.77 cm) was a continuation of the normally arising main PA (1.76 cm; Figure 1). The LMCA was seen to arise from the undersurface of the proximal right PA well beyond its aortic origin. After a median sternotomy, the aorta, left and right PA were dissected free and mobilized. A tourniquet was passed around the right PA. After establishing standard hypothermic (28 C) cardiopulmonary bypass (CPB) by high aortic and bicaval cannulation, the tourniquet around the right
Department of Cardiothoracic and Vascular Surgery, All India Institute of Medical Sciences, New Delhi, India Corresponding author: Sachin Talwar, MCh, Department of Cardiothoracic and Vascular Surgery, All India Institute of Medical Sciences, New Delhi 110029, India. Email: [email protected]
Talwar et al.
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Figure 1. Computed tomography angiograms: (a) axial thick multiplanar reconstruction demonstrating the right pulmonary artery (RPA) arising from the ascending aorta (AA), and the left pulmonary artery (LPA) arising normally; (b) curved thick multiplanar reconstruction demonstrating the anomalous origin of the of left main coronary artery (*) from the RPA.
PA was tightened to prevent run-off into the right lung. Both PA were dissected up to the hilum of the lungs. After applying an aortic crossclamp and delivering cardioplegia, the right atrium was opened, the VSD was closed using a patch, and the patent foramen ovale was closed directly. Another dose of cardioplegia was administered, and the ascending aorta was transected well above the sinotubular junction and above the origin of the right PA. The ostium of the LMCA was identified on the inferior surface of the right PA, approximately 10 mm from the aortic origin of the right PA. A 1.5-mm coronary probe was passed through the LMCA ostium, and it was noted that the LMCA ran an intramural course within the posterior wall of the aorta from where it emerged on the left side to bifurcate normally into its left anterior descending and left circumflex branches. The origin and distribution of the right coronary artery was normal. The right PA was divided from the ascending aorta, leaving a sleeve of the right PA along with the origin of the LMCA with the aorta. The aortic end was primarily sutured in 2 layers. An arteriotomy was made at the angle of the main PA and the left PA, and an end-toside anastomosis was fashioned between the right and main PA using a continuous 6/0 polypropylene suture. The transected ends of the aorta were sutured together, anterior to the reconstructed PA, using a continuous 6/0 polypropylene suture. After closing the right atrium and routine de-airing maneuvers, the aortic crossclamp was released, and the patient was weaned off CPB uneventfully with minimal inotropic support of nitroglycerine 0.05 mgkg 1min 1 and dobutamine 5 mgkg 1min 1. The CPB time was 126 min, and the aortic crossclamp time was 76 min. The child was electively ventilated for 48 h in view of PA hypertension, and he recovered uneventfully after extubation. After 6 months of follow-up, he was off all cardiac medication, a follow-up electrocardiogram was normal, and
echocardiography reveled no residual surgical defect, no gradient across the right PA, and normal flow into the LMCA.
Discussion Hemitruncus is known to be associated with a variety of intracardiac defects. Anomalous LMCA from the PA may occur in isolation or combined with other intracardiac defects.3 However, the usual site of origin of an anomalous LMCA is from the main PA; origin from a branch PA, specially the right PA, is extremely rare, and only 2 such cases have been reported in the English medical literature.4,5 To the best of our knowledge, the combination of hemitruncus, VSD, and anomalous LMCA from the right PA has not been reported previously. Usually, patients with anomalous LMCA from the main PA present with severe left ventricular dysfunction and features of myocardial ischemia, but these were not observed in our patient because the LMCA received blood at aortic pressure from the right PA which originated from the aorta. Many such patients would be operated on after an echocardiographic diagnosis only, therefore, every attempt should be made to clearly identify the origin of both coronary arteries in relation to the anomalous PA, and when needed, computed tomography angiography or magnetic resonance imaging should be performed to accurately delineate coronary artery anatomy because it has important surgical implications. Repair of isolated hemitruncus has been accomplished without CPB;2 however, this was not applicable in our patient because of the VSD and anomalous coronary artery, which necessitated institution of CPB. Another important feature of this case was that aortic transection facilitated accurate delineation of the anatomy, simplified the surgical repair, and provided excellent exposure of the proposed anastomosis site of the right
340
Asian Cardiovascular & Thoracic Annals 21(3)
Figure 2. (a) External findings on inspection: dotted lines show the proposed sites of aortic transaction and the site of detachment of the right pulmonary artery (RPA) from the aorta (Ao). The ventricles and atria are not shown for the sake of clarity. Dotted intramural part of the LMCA is shown. (b) Internal findings after aortic transaction and detachment of the RPA from the aorta. Note the ostium of the RPA from the posterior part of the ascending aorta. The arteriotomy in the MPA is also shown. The intramural LMCA is omitted for clarity. (c) The aortic end of the RPA has been closed, and implantation of the RPA into the MPA has been started. The intramural LMCA is omitted for clarity. (d) Completed reconstruction after anastomosis of the transected aortic ends. The intramural LMCA is omitted for clarity. Ao: aorta; LPA: left pulmonary artery; MPA: main pulmonary artery; LMCA: left main coronary artery; RCA: right coronary artery; RPA: right pulmonary artery.
PA to the main PA. This also prevented accidental damage to the coronary artery, which is not difficult particularly if it pursues an intramural course and emerges on the left side of the aorta. By extensive mobilization of the right and left PA, direct tissue-totissue anastomosis was possible, avoiding the use of a conduit. We did not consider unroofing of the intramural part of the coronary artery as the child weighed only 4.5 kg and we wanted to keep the procedure simple and safe. The ostium of the LMCA was wide enough, and the coronary artery did not cross any of the aortic commissures. In the event of the latter, unroofing would have been an important adjunct to obtain wide unobstructed flow into the coronary artery, without any risk of stenosis. Also, because the right PA was adequately mobilized, a segment of it could be sacrificed to provide flow into the LMCA. If the right PA is short, unroofing of the coronary would also allow shifting the ostium of the LMCA to the site of its normal origin, and give the option of dividing the right PA flush with the aorta. This case highlights a rare anomaly, and details its surgical management.
Funding This research received no specific grant from any funding agency in the public, commerical, or not-for-profit sectors.
Conflicts of interest statement None declared. Figure 2.
References 1. Kutsche LM and Van Mierop LH. Anomalous origin of a pulmonary artery from the ascending aorta: associated anomalies and pathogenesis. Am J Cardiol 1988; 61: 850–856. 2. Garg P, Talwar S, Kothari SS, Saxena A, Juneja R, Choudhary SK, et al. Anomalous origin of the branch pulmonary artery from the ascending aorta. Interact Cardiovasc Thorac Surg. Epub ahead of print Mar 30, 2012. 3. Talwar S, Bhan A, Sharma R, Choudhary SK, Airan B, Saxena A, et al. Two-coronary repair for anomalous left coronary artery from pulmonary artery. Asian Cardiovasc
Talwar et al. Thorac Ann 2000; 8: 27–31. (Available at: http://asianannals.ctsnetjournals.org (accessed May 03, 2012). 4. Rao BN, Lucas Jr RV and Edwards JE. Anomalous origin of the left coronary artery from the right pulmonary artery associated with ventricular septal defect. Chest 1970; 58: 616–620.
341 5. Driscoll DJ, Garson A and McNamara DG. Anomalous origin of the left coronary artery from the right pulmonary artery associated with complex congenital heart disease. Cathet Cardiovasc Diagn 1982; 8: 55–61.
Hemitruncus, septal defect, and anomalous coronary artery from pulmonary artery
Asian Cardiovascular & Thoracic Annals 21(3) 338–341 ß The Author(s) 2012 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/0218492312454018 aan.sagepub.com
Sachin Talwar, Palleti Rajashekar, Saurabh Kumar Gupta, Gurpreet Singh Gulati, Shiv Kumar Choudhary and Balram Airan
Abstract An 8-month-old boy with aortic origin of the right pulmonary artery, ventricular septal defect, and anomalous origin of the left main coronary artery from the right pulmonary artery, underwent uneventful single-stage surgical correction. The rarity and technical aspects of managing this condition are discussed.
Keywords Coronary vessel anomalies, heart defects, congenital, heart septal defects, ventricular, pulmonary artery
Introduction Anomalous origin of a branch pulmonary artery (PA) from the aorta (hemitruncus) is a rare congenital cardiac anomaly in which of one of the branch PA arises from the ascending aorta and the other arises from the right ventricular outflow tract in the presence of 2 semilunar valves.1 It is often associated with other intracardiac defects.2 However, the combination of hemitruncus, ventricular septal defect (VSD) and anomalous origin of the left main coronary artery (LMCA) from the right PA is extremely unusual.
Case report An 8-month-old boy, weighing 4.5 kg, presented with tachypnea, sweating during feeding, poor weight gain, and recurrent lower respiratory tract infections since birth. On examination, he appeared poorly nourished, his pulse rate was 102 beats per minute, and all peripheral pulses were palpable and synchronous. The apex beat was in the 6th intercostal space lateral to the midclavicular line. The 1st heart sound was normal, the 2nd heart sound was loud, and a grade 3/6 pansystolic murmur was heard at the left 3rd intercostal space. Chest radiography revealed left ventricular enlargement. An electrocardiogram also showed left
ventricular enlargement with no evidence of myocardial ischemia. Transthoracic echocardiography demonstrated a large perimembranous VSD with a leftto-right shunt, a patent foramen ovale, and severe PA hypertension. The right PA was seen to be dilated and arising from the aorta. There was a suspicion of the LMCA arising from the right PA. Computed tomography angiography revealed a large perimembranous VSD with the right PA (1 cm) arising from the posterior aspect of the ascending aorta, while the left PA (0.77 cm) was a continuation of the normally arising main PA (1.76 cm; Figure 1). The LMCA was seen to arise from the undersurface of the proximal right PA well beyond its aortic origin. After a median sternotomy, the aorta, left and right PA were dissected free and mobilized. A tourniquet was passed around the right PA. After establishing standard hypothermic (28 C) cardiopulmonary bypass (CPB) by high aortic and bicaval cannulation, the tourniquet around the right
Department of Cardiothoracic and Vascular Surgery, All India Institute of Medical Sciences, New Delhi, India Corresponding author: Sachin Talwar, MCh, Department of Cardiothoracic and Vascular Surgery, All India Institute of Medical Sciences, New Delhi 110029, India. Email: [email protected]
Talwar et al.
339
Figure 1. Computed tomography angiograms: (a) axial thick multiplanar reconstruction demonstrating the right pulmonary artery (RPA) arising from the ascending aorta (AA), and the left pulmonary artery (LPA) arising normally; (b) curved thick multiplanar reconstruction demonstrating the anomalous origin of the of left main coronary artery (*) from the RPA.
PA was tightened to prevent run-off into the right lung. Both PA were dissected up to the hilum of the lungs. After applying an aortic crossclamp and delivering cardioplegia, the right atrium was opened, the VSD was closed using a patch, and the patent foramen ovale was closed directly. Another dose of cardioplegia was administered, and the ascending aorta was transected well above the sinotubular junction and above the origin of the right PA. The ostium of the LMCA was identified on the inferior surface of the right PA, approximately 10 mm from the aortic origin of the right PA. A 1.5-mm coronary probe was passed through the LMCA ostium, and it was noted that the LMCA ran an intramural course within the posterior wall of the aorta from where it emerged on the left side to bifurcate normally into its left anterior descending and left circumflex branches. The origin and distribution of the right coronary artery was normal. The right PA was divided from the ascending aorta, leaving a sleeve of the right PA along with the origin of the LMCA with the aorta. The aortic end was primarily sutured in 2 layers. An arteriotomy was made at the angle of the main PA and the left PA, and an end-toside anastomosis was fashioned between the right and main PA using a continuous 6/0 polypropylene suture. The transected ends of the aorta were sutured together, anterior to the reconstructed PA, using a continuous 6/0 polypropylene suture. After closing the right atrium and routine de-airing maneuvers, the aortic crossclamp was released, and the patient was weaned off CPB uneventfully with minimal inotropic support of nitroglycerine 0.05 mgkg 1min 1 and dobutamine 5 mgkg 1min 1. The CPB time was 126 min, and the aortic crossclamp time was 76 min. The child was electively ventilated for 48 h in view of PA hypertension, and he recovered uneventfully after extubation. After 6 months of follow-up, he was off all cardiac medication, a follow-up electrocardiogram was normal, and
echocardiography reveled no residual surgical defect, no gradient across the right PA, and normal flow into the LMCA.
Discussion Hemitruncus is known to be associated with a variety of intracardiac defects. Anomalous LMCA from the PA may occur in isolation or combined with other intracardiac defects.3 However, the usual site of origin of an anomalous LMCA is from the main PA; origin from a branch PA, specially the right PA, is extremely rare, and only 2 such cases have been reported in the English medical literature.4,5 To the best of our knowledge, the combination of hemitruncus, VSD, and anomalous LMCA from the right PA has not been reported previously. Usually, patients with anomalous LMCA from the main PA present with severe left ventricular dysfunction and features of myocardial ischemia, but these were not observed in our patient because the LMCA received blood at aortic pressure from the right PA which originated from the aorta. Many such patients would be operated on after an echocardiographic diagnosis only, therefore, every attempt should be made to clearly identify the origin of both coronary arteries in relation to the anomalous PA, and when needed, computed tomography angiography or magnetic resonance imaging should be performed to accurately delineate coronary artery anatomy because it has important surgical implications. Repair of isolated hemitruncus has been accomplished without CPB;2 however, this was not applicable in our patient because of the VSD and anomalous coronary artery, which necessitated institution of CPB. Another important feature of this case was that aortic transection facilitated accurate delineation of the anatomy, simplified the surgical repair, and provided excellent exposure of the proposed anastomosis site of the right
340
Asian Cardiovascular & Thoracic Annals 21(3)
Figure 2. (a) External findings on inspection: dotted lines show the proposed sites of aortic transaction and the site of detachment of the right pulmonary artery (RPA) from the aorta (Ao). The ventricles and atria are not shown for the sake of clarity. Dotted intramural part of the LMCA is shown. (b) Internal findings after aortic transaction and detachment of the RPA from the aorta. Note the ostium of the RPA from the posterior part of the ascending aorta. The arteriotomy in the MPA is also shown. The intramural LMCA is omitted for clarity. (c) The aortic end of the RPA has been closed, and implantation of the RPA into the MPA has been started. The intramural LMCA is omitted for clarity. (d) Completed reconstruction after anastomosis of the transected aortic ends. The intramural LMCA is omitted for clarity. Ao: aorta; LPA: left pulmonary artery; MPA: main pulmonary artery; LMCA: left main coronary artery; RCA: right coronary artery; RPA: right pulmonary artery.
PA to the main PA. This also prevented accidental damage to the coronary artery, which is not difficult particularly if it pursues an intramural course and emerges on the left side of the aorta. By extensive mobilization of the right and left PA, direct tissue-totissue anastomosis was possible, avoiding the use of a conduit. We did not consider unroofing of the intramural part of the coronary artery as the child weighed only 4.5 kg and we wanted to keep the procedure simple and safe. The ostium of the LMCA was wide enough, and the coronary artery did not cross any of the aortic commissures. In the event of the latter, unroofing would have been an important adjunct to obtain wide unobstructed flow into the coronary artery, without any risk of stenosis. Also, because the right PA was adequately mobilized, a segment of it could be sacrificed to provide flow into the LMCA. If the right PA is short, unroofing of the coronary would also allow shifting the ostium of the LMCA to the site of its normal origin, and give the option of dividing the right PA flush with the aorta. This case highlights a rare anomaly, and details its surgical management.
Funding This research received no specific grant from any funding agency in the public, commerical, or not-for-profit sectors.
Conflicts of interest statement None declared. Figure 2.
References 1. Kutsche LM and Van Mierop LH. Anomalous origin of a pulmonary artery from the ascending aorta: associated anomalies and pathogenesis. Am J Cardiol 1988; 61: 850–856. 2. Garg P, Talwar S, Kothari SS, Saxena A, Juneja R, Choudhary SK, et al. Anomalous origin of the branch pulmonary artery from the ascending aorta. Interact Cardiovasc Thorac Surg. Epub ahead of print Mar 30, 2012. 3. Talwar S, Bhan A, Sharma R, Choudhary SK, Airan B, Saxena A, et al. Two-coronary repair for anomalous left coronary artery from pulmonary artery. Asian Cardiovasc
Talwar et al. Thorac Ann 2000; 8: 27–31. (Available at: http://asianannals.ctsnetjournals.org (accessed May 03, 2012). 4. Rao BN, Lucas Jr RV and Edwards JE. Anomalous origin of the left coronary artery from the right pulmonary artery associated with ventricular septal defect. Chest 1970; 58: 616–620.
341 5. Driscoll DJ, Garson A and McNamara DG. Anomalous origin of the left coronary artery from the right pulmonary artery associated with complex congenital heart disease. Cathet Cardiovasc Diagn 1982; 8: 55–61.
