Case Study
One-stage repair of tetralogy of Fallot with coarctation of the aorta
Asian Cardiovascular & Thoracic Annals 2014, Vol. 22(7) 855–857 ß The Author(s) 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/0218492313487080 aan.sagepub.com
Zeena Makhija1, Sitaraman Radhakrishnan2, Apporva Goel3 and Rajesh Sharma1
Abstract We describe the rare case of a 10-month-old girl who had coarctation of the aorta in association with tetralogy of Fallot. The surgical management and postoperative course is described. This case highlights the rare association of coarctation with tetralogy of Fallot, with a large intracardiac right-to-left shunt. Although an exception to the rule, it challenges the reduced fetal blood flow theory and the smooth muscle cell migration theory as embryological explanations for the development of coarctation.
Keywords Aortic coarctation, tetralogy of fallot
Introduction Complex coarctation of the aorta (CoA) occurs in association with left-sided obstructive lesions of the heart, which cause a left-to-right intracardiac shunt. Hemodynamic theory proposes that reduced blood flow through the fetal aortic arch leads to subsequent development of coarctation.1 We describe a rare case of CoA with tetralogy of Fallot (TOF), which causes a right-to-left shunt, and discuss the embryology. We speculate whether the theory of reduced fetal blood flow across the aortic isthmus is credible in this configuration.
Case report A 10-month-old girl presented with fatigue and poor weight gain. On examination, a systolic murmur grade 3/6 was present at the left upper sternal border. Cyanosis was noted. All peripheral pulses were weak. Transthoracic echocardiography revealed a nonrestrictive perimembranous ventricular septal defect with severe infundibular and valvular stenosis. She had confluent branch pulmonary arteries (PA) with left PA origin stenosis, a patent ductus arteriosus with left-to-right shunting, and severe biventricular dysfunction. There was severe CoA of a right aortic arch (gradient: 49 mm Hg). A computed tomography-angiogram delineated narrowing of the origins of the right carotid and right subclavian artery (SCA); the latter arose from the coarcted segment (Figure 1). The left SCA had an
anomalous origin from the descending aorta beyond the coarcted segment, and an aberrant retroesophageal course (Figure 2). The left common carotid artery had a proximal diverticulum but was normal in course and calibre (Figure 3). The patient underwent complete intracardiac repair. A routine median sternotomy was performed. The thymus was excised. A pericardial patch was harvested and treated with 6% glutaraldehyde for 15 min. The right aortic arch, which arose high in the neck, was dissected out along with all its branches. Due to the high ascent, the descending aorta came off at a sharp angle, and the angulation between the descending and ascending aorta was the site of coarctation from which the right SCA also arose. High ascending aortic cannulation was chosen, using a 10F Bio-Medicus cannula. Bicaval cannulation was utilized for venous drainage, and cooling to 18 C was started. The patent ductus arteriosus was sutureligated and divided. During cooling, the arch vessels 1 Division of Congenital Cardiac Surgery, Fortis Escorts Heart Research Institute, New Delhi, India 2 Department of Pediatric Cardiology, Fortis Escorts Heart Research Institute, New Delhi, India 3 Department of Radiology, Fortis Escorts Heart Institute and Research Center, India
Corresponding author: Zeena Makhija, Division of Congenital Cardiac Surgery, Fortis Escorts Heart Research Institute, New Delhi, India. Email: [email protected]
Downloaded from aan.sagepub.com at OAKLAND UNIV on June 2, 2015
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Asian Cardiovascular & Thoracic Annals 22(7)
Figure 1. Stenosed origins of right carotid and right subclavian arteries.
Figure 3. Proximal diverticulum at the origin of left carotid artery.
A vent was placed in right superior pulmonary vein. The aorta was crossclamped and cardioplegia was delivered into the ascending aorta (St. Thomas’ Hospital solution, 20 mLkg 1, 8 C). The right atrium was opened and stays were applied. The tricuspid valve leaflets were retracted. Infundibular resection was carried out while preserving the moderator band. The ventricular septal defect was closed using an autologous tanned pericardial patch. A transannular patch extending to the left PA origin was placed with monocusp implantation, using Gore-Tex pericardial membrane. The right atrium was closed. The heart was deaired and the crossclamp was released. The heart returned to sinus rhythm spontaneously. The patient was weaned off cardiopulmonary bypass at 34 C on dobutamine support. Decannulation was completed, and hemostasis was secured. The chest was closed using a blood bag over the left atrial line and pacing wires. Figure 2. Aberrant retroesophageal course of left subclavian artery.
Discussion
and proximal descending aorta were mobilized and looped. Care was taken to preserve the vagus, phrenic, and recurrent laryngeal nerves. When the rectal temperature was less than 18 C, a crossclamp was placed to occlude the descending aorta and a C-clamp was placed on the undersurface of the proximal aortic arch, excluding the neck vessels. The descending aorta was anastomosed to the back wall of the dilated ascending aorta during a period of nonperfusion to the lower body. The proximal aorta was ligated and transfixed and left to supply the right SCA and right carotid artery. The patient was gradually warmed to 26 C.
Frequently, CoA is associated with left heart anomalies. This credits the reduced fetal blood flow theory with the formation of CoA. Histologic examination of the resected coarcted segment often reveals an intimal shelf, similar to myxomatous tissue seen in the ductus. Smooth muscle cells infiltrating the aorta and forming a circumferential noose around the aorta have also been demonstrated.2 Their contraction in the early postnatal period is purported to give rise to coarctation. It has been hypothesized that ductal flow from the PA to the aorta in left heart obstructive lesions results in migration of smooth muscle cells into the proximal descending aorta. Interestingly, that is why coarctation has
Downloaded from aan.sagepub.com at OAKLAND UNIV on June 2, 2015
Makhija et al.
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only been reported twice before in patients with rightto-left intracardiac shunts (such as TOF) where the aortic outflow is greater.3,4 In this case, there was a left-sided duct with coarctation of the right-sided aortic arch, with no evidence of bilateral ducts. This means that another explanation for CoA in this combination of lesions has to be evoked. Right heart obstructive anomalies result in ductal flow from the aorta to the PA, which opposes the natural direction of migratory cells. Increased antegrade aortic flow deters the proliferation of ductal tissue into the aorta. The aortic arch is derived from pharyngeal arches that develop as bilateral symmetric structures but undergo a programmed sequence of regression and apoptotic resorption to give rise to various branches.5 In this case, the hypoplastic segment extended well beyond the right SCA, pointing to involvement of the left embryonic dorsal aorta. The separate origins of the right external and internal carotid arteries from the arch as independent vessels points to the persistence of a right dorsal aorta between the third and fourth arches (which normally obliterate). Inadvertently, the right SCA (persistent 4th pharyngeal arch) became the right innominate artery in this case, which explains its bend at a sharp right angle to the transverse arch and the apparent right subclavian ostial stenosis. The child had no symptoms of right ventricular outflow tract obstruction. She had failure to thrive, pulmonary issues, and recurrent chest infections. Because her systemic outlet was obstructed, the increased systemic afterload probably resulted in sufficient pulmonary blood flow despite severe right ventricular outflow tract obstruction. Preoperative balloon dilatation of the coarctation was planned but abandoned due to the proximity of the right carotid and right subclavian origins to the coarcted segment. The choice of therapeutic strategies included staged coarctation repair followed by TOF repair or single-stage repair of both defects. Due to severe biventricular dysfunction, we decided to address both issues simultaneously. Postoperative recovery was slow due to persistent left ventricular dysfunction. Echocardiography showed turbulence at the anastomotic site of the coarctation, which was dilated in the catheter laboratory. As all limb vessels (both femoral, left subclavian) either arose distal to coarctation or were involved in the coarctation, residual obstruction could not be diagnosed clinically. Catheterization was repeated, a gradient of 26 mm Hg at the coarctation was detected, and balloon dilatation was performed (Figure 4). Subsequently, the child could be weaned from the ventilator and discharged. The left ventricular ejection fraction improved to 35% from a preoperative value of 15%. At the 1-year followup, the child was in New York Heart Association functional class I with a reasonable quality of life.
Figure 4. Postoperative dilatation of the residual coarct segment.
Echocardiography revealed an ejection fraction of 40% with no significant gradient across the aortic arch, an acceptable right ventricular outflow tract gradient, and mild pulmonary regurgitation. This case highlights the rare association of CoA with TOF, with a large intracardiac right-to-left shunt. Although an exception to the rule, it challenges the reduced fetal blood flow theory and the smooth muscle cell migration theory of embryological explanations for the development of CoA. Our surgical strategy shows that one-stage repair may be a successful treatment for this combination of defects, despite severe biventricular dysfunction. Funding This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.
Conflicts of interest statement None declared.
References 1. Campbell M and Polani PE. The aetiology of coarctation of the aorta. Lancet 1961; 1(7175): 463–468. 2. Jonas RA. Coarctation: do we need to resect ductal tissue? Ann Thorac Surg 1991; 52: 604–607. 3. Elami A, Rein AJ, Preminger TJ and Milgalter E. Tetralogy of Fallot, absent pulmonary valve, partial anomalous pulmonary venous return and coarctation of the aorta. Int J Cardiol 1995; 52: 203–206. 4. Bullaboy CA, Derkac WM, Johnson DH and Jennings RB Jr. Tetralogy of Fallot and coarctation of the aorta: successful repair in an infant. Ann Thorac Surg 1984; 38: 400–401. 5. Anfossi C. Anatomo-surgical study of the aortic arch and its large branches. I. Arch Sci Med (Torino) 1955; 99: 400–417.
Downloaded from aan.sagepub.com at OAKLAND UNIV on June 2, 2015
One-stage repair of tetralogy of Fallot with coarctation of the aorta
Asian Cardiovascular & Thoracic Annals 2014, Vol. 22(7) 855–857 ß The Author(s) 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/0218492313487080 aan.sagepub.com
Zeena Makhija1, Sitaraman Radhakrishnan2, Apporva Goel3 and Rajesh Sharma1
Abstract We describe the rare case of a 10-month-old girl who had coarctation of the aorta in association with tetralogy of Fallot. The surgical management and postoperative course is described. This case highlights the rare association of coarctation with tetralogy of Fallot, with a large intracardiac right-to-left shunt. Although an exception to the rule, it challenges the reduced fetal blood flow theory and the smooth muscle cell migration theory as embryological explanations for the development of coarctation.
Keywords Aortic coarctation, tetralogy of fallot
Introduction Complex coarctation of the aorta (CoA) occurs in association with left-sided obstructive lesions of the heart, which cause a left-to-right intracardiac shunt. Hemodynamic theory proposes that reduced blood flow through the fetal aortic arch leads to subsequent development of coarctation.1 We describe a rare case of CoA with tetralogy of Fallot (TOF), which causes a right-to-left shunt, and discuss the embryology. We speculate whether the theory of reduced fetal blood flow across the aortic isthmus is credible in this configuration.
Case report A 10-month-old girl presented with fatigue and poor weight gain. On examination, a systolic murmur grade 3/6 was present at the left upper sternal border. Cyanosis was noted. All peripheral pulses were weak. Transthoracic echocardiography revealed a nonrestrictive perimembranous ventricular septal defect with severe infundibular and valvular stenosis. She had confluent branch pulmonary arteries (PA) with left PA origin stenosis, a patent ductus arteriosus with left-to-right shunting, and severe biventricular dysfunction. There was severe CoA of a right aortic arch (gradient: 49 mm Hg). A computed tomography-angiogram delineated narrowing of the origins of the right carotid and right subclavian artery (SCA); the latter arose from the coarcted segment (Figure 1). The left SCA had an
anomalous origin from the descending aorta beyond the coarcted segment, and an aberrant retroesophageal course (Figure 2). The left common carotid artery had a proximal diverticulum but was normal in course and calibre (Figure 3). The patient underwent complete intracardiac repair. A routine median sternotomy was performed. The thymus was excised. A pericardial patch was harvested and treated with 6% glutaraldehyde for 15 min. The right aortic arch, which arose high in the neck, was dissected out along with all its branches. Due to the high ascent, the descending aorta came off at a sharp angle, and the angulation between the descending and ascending aorta was the site of coarctation from which the right SCA also arose. High ascending aortic cannulation was chosen, using a 10F Bio-Medicus cannula. Bicaval cannulation was utilized for venous drainage, and cooling to 18 C was started. The patent ductus arteriosus was sutureligated and divided. During cooling, the arch vessels 1 Division of Congenital Cardiac Surgery, Fortis Escorts Heart Research Institute, New Delhi, India 2 Department of Pediatric Cardiology, Fortis Escorts Heart Research Institute, New Delhi, India 3 Department of Radiology, Fortis Escorts Heart Institute and Research Center, India
Corresponding author: Zeena Makhija, Division of Congenital Cardiac Surgery, Fortis Escorts Heart Research Institute, New Delhi, India. Email: [email protected]
Downloaded from aan.sagepub.com at OAKLAND UNIV on June 2, 2015
856
Asian Cardiovascular & Thoracic Annals 22(7)
Figure 1. Stenosed origins of right carotid and right subclavian arteries.
Figure 3. Proximal diverticulum at the origin of left carotid artery.
A vent was placed in right superior pulmonary vein. The aorta was crossclamped and cardioplegia was delivered into the ascending aorta (St. Thomas’ Hospital solution, 20 mLkg 1, 8 C). The right atrium was opened and stays were applied. The tricuspid valve leaflets were retracted. Infundibular resection was carried out while preserving the moderator band. The ventricular septal defect was closed using an autologous tanned pericardial patch. A transannular patch extending to the left PA origin was placed with monocusp implantation, using Gore-Tex pericardial membrane. The right atrium was closed. The heart was deaired and the crossclamp was released. The heart returned to sinus rhythm spontaneously. The patient was weaned off cardiopulmonary bypass at 34 C on dobutamine support. Decannulation was completed, and hemostasis was secured. The chest was closed using a blood bag over the left atrial line and pacing wires. Figure 2. Aberrant retroesophageal course of left subclavian artery.
Discussion
and proximal descending aorta were mobilized and looped. Care was taken to preserve the vagus, phrenic, and recurrent laryngeal nerves. When the rectal temperature was less than 18 C, a crossclamp was placed to occlude the descending aorta and a C-clamp was placed on the undersurface of the proximal aortic arch, excluding the neck vessels. The descending aorta was anastomosed to the back wall of the dilated ascending aorta during a period of nonperfusion to the lower body. The proximal aorta was ligated and transfixed and left to supply the right SCA and right carotid artery. The patient was gradually warmed to 26 C.
Frequently, CoA is associated with left heart anomalies. This credits the reduced fetal blood flow theory with the formation of CoA. Histologic examination of the resected coarcted segment often reveals an intimal shelf, similar to myxomatous tissue seen in the ductus. Smooth muscle cells infiltrating the aorta and forming a circumferential noose around the aorta have also been demonstrated.2 Their contraction in the early postnatal period is purported to give rise to coarctation. It has been hypothesized that ductal flow from the PA to the aorta in left heart obstructive lesions results in migration of smooth muscle cells into the proximal descending aorta. Interestingly, that is why coarctation has
Downloaded from aan.sagepub.com at OAKLAND UNIV on June 2, 2015
Makhija et al.
857
only been reported twice before in patients with rightto-left intracardiac shunts (such as TOF) where the aortic outflow is greater.3,4 In this case, there was a left-sided duct with coarctation of the right-sided aortic arch, with no evidence of bilateral ducts. This means that another explanation for CoA in this combination of lesions has to be evoked. Right heart obstructive anomalies result in ductal flow from the aorta to the PA, which opposes the natural direction of migratory cells. Increased antegrade aortic flow deters the proliferation of ductal tissue into the aorta. The aortic arch is derived from pharyngeal arches that develop as bilateral symmetric structures but undergo a programmed sequence of regression and apoptotic resorption to give rise to various branches.5 In this case, the hypoplastic segment extended well beyond the right SCA, pointing to involvement of the left embryonic dorsal aorta. The separate origins of the right external and internal carotid arteries from the arch as independent vessels points to the persistence of a right dorsal aorta between the third and fourth arches (which normally obliterate). Inadvertently, the right SCA (persistent 4th pharyngeal arch) became the right innominate artery in this case, which explains its bend at a sharp right angle to the transverse arch and the apparent right subclavian ostial stenosis. The child had no symptoms of right ventricular outflow tract obstruction. She had failure to thrive, pulmonary issues, and recurrent chest infections. Because her systemic outlet was obstructed, the increased systemic afterload probably resulted in sufficient pulmonary blood flow despite severe right ventricular outflow tract obstruction. Preoperative balloon dilatation of the coarctation was planned but abandoned due to the proximity of the right carotid and right subclavian origins to the coarcted segment. The choice of therapeutic strategies included staged coarctation repair followed by TOF repair or single-stage repair of both defects. Due to severe biventricular dysfunction, we decided to address both issues simultaneously. Postoperative recovery was slow due to persistent left ventricular dysfunction. Echocardiography showed turbulence at the anastomotic site of the coarctation, which was dilated in the catheter laboratory. As all limb vessels (both femoral, left subclavian) either arose distal to coarctation or were involved in the coarctation, residual obstruction could not be diagnosed clinically. Catheterization was repeated, a gradient of 26 mm Hg at the coarctation was detected, and balloon dilatation was performed (Figure 4). Subsequently, the child could be weaned from the ventilator and discharged. The left ventricular ejection fraction improved to 35% from a preoperative value of 15%. At the 1-year followup, the child was in New York Heart Association functional class I with a reasonable quality of life.
Figure 4. Postoperative dilatation of the residual coarct segment.
Echocardiography revealed an ejection fraction of 40% with no significant gradient across the aortic arch, an acceptable right ventricular outflow tract gradient, and mild pulmonary regurgitation. This case highlights the rare association of CoA with TOF, with a large intracardiac right-to-left shunt. Although an exception to the rule, it challenges the reduced fetal blood flow theory and the smooth muscle cell migration theory of embryological explanations for the development of CoA. Our surgical strategy shows that one-stage repair may be a successful treatment for this combination of defects, despite severe biventricular dysfunction. Funding This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.
Conflicts of interest statement None declared.
References 1. Campbell M and Polani PE. The aetiology of coarctation of the aorta. Lancet 1961; 1(7175): 463–468. 2. Jonas RA. Coarctation: do we need to resect ductal tissue? Ann Thorac Surg 1991; 52: 604–607. 3. Elami A, Rein AJ, Preminger TJ and Milgalter E. Tetralogy of Fallot, absent pulmonary valve, partial anomalous pulmonary venous return and coarctation of the aorta. Int J Cardiol 1995; 52: 203–206. 4. Bullaboy CA, Derkac WM, Johnson DH and Jennings RB Jr. Tetralogy of Fallot and coarctation of the aorta: successful repair in an infant. Ann Thorac Surg 1984; 38: 400–401. 5. Anfossi C. Anatomo-surgical study of the aortic arch and its large branches. I. Arch Sci Med (Torino) 1955; 99: 400–417.
Downloaded from aan.sagepub.com at OAKLAND UNIV on June 2, 2015
