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Aorto–Left Atrial Tunnel: A Rare Entity
Aorto–Left Atrial Tunnel: A Rare Entity Sajiv K. Paul, MCh, Trushar P. Gajjar, DNB, and Neelam B. Desai, MCh, DNB Sri Sathya Sai Institute of Higher Medical Sciences, Prasanthigram, District Anantapur, Andhra Pradesh, India
Aorto–left atrial tunnel (ALAT) is a vascular channel that originates from 1 of the sinuses of Valsalva and terminates in the left atrium. The aorto–left atrial tunnel is an extremely rare anomaly. We describe here a case of congenital aorto–left atrial tunnel in a 4-year-old child who underwent successful surgical ligation with good immediate and early results. (Ann Thorac Surg 2013;95:e121–2) © 2013 by The Society of Thoracic Surgeons
A
orto–left atrial tunnel (ALAT) is a vascular channel that originates from 1 of the sinuses of Valsalva and terminates in the left atrium [1–5]. The ALAT is an extremely rare anomaly. We describe here a case of congenital ALAT in a 4-year-old child who underwent successful off-pump surgical ligation. A 4-year-old boy presented with recurrent respiratory tract infection. On examination there was grade 3/6 continuous murmur at the left upper sternal border, with bounding peripheral pulses. Chest roentgenography showed a cardiothoracic ratio of 70%, a left ventricular type of apex, and left atrial enlargement (double atrial shadow). Electrocardiography showed sinus rhythm, left atrial enlargement, and left ventricular hypertrophy. Transthoracic 2- and 3-dimensional echocardiography showed a large tunnel arising from the left coronary sinus running posteriorly and opening into the left atrium, and the left coronary artery arising from the proximal part of the tunnel (Fig 1). The aortic root angiogram in lateral view (Fig 2) showed a tunnel arising from the left coronary sinus and opening into the left atrium. The left anterior descending coronary artery and left circumflex artery were seen arising from the tunnel with an apparently normal course. In view of no other associated intracardiac anomaly and our large experience with ligation of aorto–right atrial tunnel, it was decided to ligate the tunnel. A conventional median sternotomy was performed. A dry setup of cardiopulmonary bypass (CPB) was kept on standby. The intraoperative findings showed cardiomegaly, left atrial enlargement with a dilatated aorta, and a large tunnel-like structure of approximately 1 cm in diameter arising from the left coronary sinus and coursing posteriorly and inferiorly over the roof of the left atrium and entering into it. A normal-sized left anterior descending coronary artery and left circumflex coronary artery were seen to originate from the proximal part of the tunnel and course in their normal route. The right atrial appendage was ligated with silk and retracted for
Fig 1. Transthoracic 3-dimensional echocardiogram showing tunnel arising from left coronary sinus and opening into roof of left atrium with left coronary artery arising from proximal portion of tunnel. (AOV ⫽ aortic valve; LA ⫽ left atrium; LCA ⫽ left coronary artery.)
exposure. The tunnel was dissected from the roof of the left atrium between the aorta and the superior vena cava and was doubly looped with No. 2 silk sutures beyond the coronary artery takeoff (Fig 3). A snugger was placed and tightened over the proximal ligature for approximately 2 minutes, and all the electrocardiographic leads were checked for ischemic changes. The tunnel was doubly ligated under controlled hypotension after confirming there was no evidence of ischemia. The postop-
Accepted for publication Nov 6, 2012. Address correspondence to Dr Gajjar, Department of Cardiothoracic and Vascular Surgery, Sri Sathya Sai Institute of Higher Medical Sciences, Prasanthigram–515134, District Anantapur, Andhra Pradesh, India; e-mail: [email protected].
© 2013 by The Society of Thoracic Surgeons Published by Elsevier Inc
Fig 2. Aortic root angiogram in lateral view showing tunnel arising from left coronary sinus and opening into roof of left atrium with left coronary artery (LCA) arising from proximal portion of tunnel. (LA ⫽ left atrium; RCA ⫽ right coronary artery.) 0003-4975/$36.00 http://dx.doi.org/10.1016/j.athoracsur.2012.11.009
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CASE REPORT PAUL ET AL AORTO-LEFT ATRIAL TUNNEL
Fig 3. Intraoperative photograph taken from the head end of the patient showing doubly looped tunnel between aorta and superior vena cava/aorta. (Ao ⫽ aorta; MPA ⫽ main pulmonary artery; RAA ⫽ right atrial appendage; RVOT ⫽ right ventricular outflow tract; SVC ⫽ superior vena cava.)
erative course was uneventful. Immediate postoperative echocardiography showed no flow across the tunnel and good biventricular function. The postoperative echocardiogram obtained before discharge confirmed complete obliteration of the tunnel beyond the ligatures. At 3 months’ follow-up, the patient was asymptomatic, and imaging revealed normal coronary arteries, no aneurysmal changes, and progressive obliteration of the tunnel with remodeling of the aortic root.
Comment A congenital tunnel between the root of the aorta and the left atrium is considered the least common form of aortic cameral communication [1–5]. The ALAT was first described by Yu and colleagues[1] and Freedom and colleagues [3] in 1979. ALAT is of 2 varieties, congenital and acquired. Acquired ALAT can occur from trauma and infective endocarditis or a rheumatic pathologic process [5]. The clinical presentation ranges from an asymptomatic precordial murmur to congestive heart failure [5]. The embryologic background and pathogenesis of this lesion are attributable either to an aneurysmal dilatation of the sinus node artery or to a congenital weakness of the aortic media, [1, 5, 6] leading to progressive enlargement of the tunnel and rupture into the low-pressure left atrium [6]. The lesion can be diagnosed with echocardiography, cardiac catheterization, and computed tomographic angiography [1– 6]. In view of complications, early therapy is recommended in asymptomatic patients or in those with a hemodynamically insignificant shunt [5, 6]. The
Ann Thorac Surg 2013;95:e121–2
available treatments are catheter-based intervention, external ligation under controlled hypotension, or surgical closure under CPB. From our experience [6] with aorto– right atrial tunnel, coil embolization of the tunnel is recommended provided that the atrial end of the tunnel is small or there is a constriction in the course of it and a coil size is available for the size of the tunnel. Ligation of the tunnel can be performed between the superior vena cava and aorta under controlled hypotension, taking care not to compromise the coronary ostia. The open surgical approach is advisable with an associated intracardiac anomaly, and closure of the left atrial orifice alone on CPB may suffice. In our patient, in view of the left coronary ostium arising from the proximal portion of the tunnel and the absence of an associated intracardiac anomaly, we adopted the safer approach of external ligation, leaving a patent cul-de-sac at the aortic end. We considered the possibility of mural thrombosis, its extension or embolism into the coronary branches, and secondary infection in the remnant portion of the tunnel, and therefore placed the child under close clinical and imaging follow-up. In conclusion, ALAT is a rare anomaly. It is often detected during the evaluation of a heart murmur in an asymptomatic patient. The diagnosis can be achieved by echocardiography and aortic root angiography. Surgical closure should be recommended soon after diagnosis because continued patency of the tunnel might predispose patients to the risk of volume overload, congestive cardiac failure, aneurysm formation, infective endocarditis, spontaneous rupture, and increased surgical mortality with age. Coil embolization is a useful modality in selected patients. Surgical options include ligation of the tunnel or direct closure of the atrial opening. Immediate and early results are satisfactory.
References 1. Yu LC, Bharati S, Thilenius O, Lamberti J, Lev M, Arcilla RA. Congenital aortico-left atrial tunnel. Pediatr Cardiol 1979/ 1980;1:153– 8. 2. Jaen R, Fermin H, Velarde H, Lariet A, Silva G. Aorto-left atrial fistula. J Cardiovasc Surg (Torino) 1986;27:355– 8. 3. Freedom RM, Mawson JB, Benson LN. Congenital Heart Disease: Textbook of angiocardiography. Armonk, NY: Futura Publishing; 1997:893. 4. Ozbarlas N, Erdem S, Kucukosmanoglu O, Poyrazoglu H, Salih OK. Congenital aorto-left atrial tunnel: an unusual communication: a case report. Heart Surg Forum 2007;10: E21–3. 5. Maoldomhnaigh CO, Ramsay JM, Finley JP, Andrews D, Murray C. Bilateral aortico-atrial tunnels. Pediatr Cardiol 2011;32:1199 –201. 6. Gajjar T, Voleti C, Matta R, Iyer R, Dash PK, Desai N. Aorta-right atrial tunnel: clinical presentation, diagnostic criteria, and surgical options. J Thorac Cardiovasc Surg 2005;30: 1287–92.
Aorto–left atrial tunnel (ALAT) is a vascular channel that originates from 1 of the sinuses of Valsalva and terminates in the left atrium. The aorto–left atrial tunnel is an extremely rare anomaly. We describe here a case of congenital aorto–left atrial tunnel in a 4-year-old child who underwent successful surgical ligation with good immediate and early results. (Ann Thorac Surg 2013;95:e121–2) © 2013 by The Society of Thoracic Surgeons
A
orto–left atrial tunnel (ALAT) is a vascular channel that originates from 1 of the sinuses of Valsalva and terminates in the left atrium [1–5]. The ALAT is an extremely rare anomaly. We describe here a case of congenital ALAT in a 4-year-old child who underwent successful off-pump surgical ligation. A 4-year-old boy presented with recurrent respiratory tract infection. On examination there was grade 3/6 continuous murmur at the left upper sternal border, with bounding peripheral pulses. Chest roentgenography showed a cardiothoracic ratio of 70%, a left ventricular type of apex, and left atrial enlargement (double atrial shadow). Electrocardiography showed sinus rhythm, left atrial enlargement, and left ventricular hypertrophy. Transthoracic 2- and 3-dimensional echocardiography showed a large tunnel arising from the left coronary sinus running posteriorly and opening into the left atrium, and the left coronary artery arising from the proximal part of the tunnel (Fig 1). The aortic root angiogram in lateral view (Fig 2) showed a tunnel arising from the left coronary sinus and opening into the left atrium. The left anterior descending coronary artery and left circumflex artery were seen arising from the tunnel with an apparently normal course. In view of no other associated intracardiac anomaly and our large experience with ligation of aorto–right atrial tunnel, it was decided to ligate the tunnel. A conventional median sternotomy was performed. A dry setup of cardiopulmonary bypass (CPB) was kept on standby. The intraoperative findings showed cardiomegaly, left atrial enlargement with a dilatated aorta, and a large tunnel-like structure of approximately 1 cm in diameter arising from the left coronary sinus and coursing posteriorly and inferiorly over the roof of the left atrium and entering into it. A normal-sized left anterior descending coronary artery and left circumflex coronary artery were seen to originate from the proximal part of the tunnel and course in their normal route. The right atrial appendage was ligated with silk and retracted for
Fig 1. Transthoracic 3-dimensional echocardiogram showing tunnel arising from left coronary sinus and opening into roof of left atrium with left coronary artery arising from proximal portion of tunnel. (AOV ⫽ aortic valve; LA ⫽ left atrium; LCA ⫽ left coronary artery.)
exposure. The tunnel was dissected from the roof of the left atrium between the aorta and the superior vena cava and was doubly looped with No. 2 silk sutures beyond the coronary artery takeoff (Fig 3). A snugger was placed and tightened over the proximal ligature for approximately 2 minutes, and all the electrocardiographic leads were checked for ischemic changes. The tunnel was doubly ligated under controlled hypotension after confirming there was no evidence of ischemia. The postop-
Accepted for publication Nov 6, 2012. Address correspondence to Dr Gajjar, Department of Cardiothoracic and Vascular Surgery, Sri Sathya Sai Institute of Higher Medical Sciences, Prasanthigram–515134, District Anantapur, Andhra Pradesh, India; e-mail: [email protected].
© 2013 by The Society of Thoracic Surgeons Published by Elsevier Inc
Fig 2. Aortic root angiogram in lateral view showing tunnel arising from left coronary sinus and opening into roof of left atrium with left coronary artery (LCA) arising from proximal portion of tunnel. (LA ⫽ left atrium; RCA ⫽ right coronary artery.) 0003-4975/$36.00 http://dx.doi.org/10.1016/j.athoracsur.2012.11.009
e122
CASE REPORT PAUL ET AL AORTO-LEFT ATRIAL TUNNEL
Fig 3. Intraoperative photograph taken from the head end of the patient showing doubly looped tunnel between aorta and superior vena cava/aorta. (Ao ⫽ aorta; MPA ⫽ main pulmonary artery; RAA ⫽ right atrial appendage; RVOT ⫽ right ventricular outflow tract; SVC ⫽ superior vena cava.)
erative course was uneventful. Immediate postoperative echocardiography showed no flow across the tunnel and good biventricular function. The postoperative echocardiogram obtained before discharge confirmed complete obliteration of the tunnel beyond the ligatures. At 3 months’ follow-up, the patient was asymptomatic, and imaging revealed normal coronary arteries, no aneurysmal changes, and progressive obliteration of the tunnel with remodeling of the aortic root.
Comment A congenital tunnel between the root of the aorta and the left atrium is considered the least common form of aortic cameral communication [1–5]. The ALAT was first described by Yu and colleagues[1] and Freedom and colleagues [3] in 1979. ALAT is of 2 varieties, congenital and acquired. Acquired ALAT can occur from trauma and infective endocarditis or a rheumatic pathologic process [5]. The clinical presentation ranges from an asymptomatic precordial murmur to congestive heart failure [5]. The embryologic background and pathogenesis of this lesion are attributable either to an aneurysmal dilatation of the sinus node artery or to a congenital weakness of the aortic media, [1, 5, 6] leading to progressive enlargement of the tunnel and rupture into the low-pressure left atrium [6]. The lesion can be diagnosed with echocardiography, cardiac catheterization, and computed tomographic angiography [1– 6]. In view of complications, early therapy is recommended in asymptomatic patients or in those with a hemodynamically insignificant shunt [5, 6]. The
Ann Thorac Surg 2013;95:e121–2
available treatments are catheter-based intervention, external ligation under controlled hypotension, or surgical closure under CPB. From our experience [6] with aorto– right atrial tunnel, coil embolization of the tunnel is recommended provided that the atrial end of the tunnel is small or there is a constriction in the course of it and a coil size is available for the size of the tunnel. Ligation of the tunnel can be performed between the superior vena cava and aorta under controlled hypotension, taking care not to compromise the coronary ostia. The open surgical approach is advisable with an associated intracardiac anomaly, and closure of the left atrial orifice alone on CPB may suffice. In our patient, in view of the left coronary ostium arising from the proximal portion of the tunnel and the absence of an associated intracardiac anomaly, we adopted the safer approach of external ligation, leaving a patent cul-de-sac at the aortic end. We considered the possibility of mural thrombosis, its extension or embolism into the coronary branches, and secondary infection in the remnant portion of the tunnel, and therefore placed the child under close clinical and imaging follow-up. In conclusion, ALAT is a rare anomaly. It is often detected during the evaluation of a heart murmur in an asymptomatic patient. The diagnosis can be achieved by echocardiography and aortic root angiography. Surgical closure should be recommended soon after diagnosis because continued patency of the tunnel might predispose patients to the risk of volume overload, congestive cardiac failure, aneurysm formation, infective endocarditis, spontaneous rupture, and increased surgical mortality with age. Coil embolization is a useful modality in selected patients. Surgical options include ligation of the tunnel or direct closure of the atrial opening. Immediate and early results are satisfactory.
References 1. Yu LC, Bharati S, Thilenius O, Lamberti J, Lev M, Arcilla RA. Congenital aortico-left atrial tunnel. Pediatr Cardiol 1979/ 1980;1:153– 8. 2. Jaen R, Fermin H, Velarde H, Lariet A, Silva G. Aorto-left atrial fistula. J Cardiovasc Surg (Torino) 1986;27:355– 8. 3. Freedom RM, Mawson JB, Benson LN. Congenital Heart Disease: Textbook of angiocardiography. Armonk, NY: Futura Publishing; 1997:893. 4. Ozbarlas N, Erdem S, Kucukosmanoglu O, Poyrazoglu H, Salih OK. Congenital aorto-left atrial tunnel: an unusual communication: a case report. Heart Surg Forum 2007;10: E21–3. 5. Maoldomhnaigh CO, Ramsay JM, Finley JP, Andrews D, Murray C. Bilateral aortico-atrial tunnels. Pediatr Cardiol 2011;32:1199 –201. 6. Gajjar T, Voleti C, Matta R, Iyer R, Dash PK, Desai N. Aorta-right atrial tunnel: clinical presentation, diagnostic criteria, and surgical options. J Thorac Cardiovasc Surg 2005;30: 1287–92.