Pediatr Cardiol 13:33-36, 1992
Pediatric Cardiology 9 Springer-VerlagNew York Inc. 1992
Case Reports Acquired Coarctation of the Aorta Thomas J. S t a r c , 1 Sara J. Abramson, 2 Fredrick Z. Bierman, 1 Joan A. Regan, 1 Anneliese L. Sitarz, 1 Eric A. Rose, 3 R. Peter Altman, 3 Margaret H. Collins, 4 and Sylvia P. Griffiths~ Departments of ~Pediatrics, -'Radiology, ~Surgery, and 4pathology, Columbia University, College of Physicians and Surgeons, New York, New York, USA
SUMMARY. Coarctation of the aorta is usually caused by a congenital narrowing of the aorta. This report describes two children who developed hypertension secondary to an acquired coarc l tation of the aorta. In one patient the coarctation was temporally related to umbilical artery catheterization and was associated with thrombosis and aneurysmal dilatation of the aorta. In the second patient, the coarctatiun occurred after surgical aortotomy during the removal of an intrathoracic neuroblastoma. Patients who have interventional damage to the aorta should be periodically examined for the appearance of a coarctation. Although an acquired coarctation of the aorta is an infrequent complication of invasive or surgical procedures, it should be identified since it represents a remediable cause of hypertension in children. KEY WORDS: Coarctation of the a o r t a - H y p e r t e n s i o n - Children
Coarctation of the aorta most commonly occurs because of a congenital narrowing of the aorta and is usually present at the time of birth. This report describes two children who developed an acquired coarctation of the aorta manifested by upper extremity hypertension and diminished femoral pulses. In the first patient the coarctation was associated with thrombosis and aneurysmal dilatation of the aorta which was temporally related to umbilical artery catheterization. In the second patient the acquired coarctation occurred after surgical aortotomy. Although an acquired coarctation is an infrequent complication of invasive or surgical procedures, it should be identified since it represents a remediable cause of hypertension in infants and children. Case Reports Case 1 The patient was a full-term infant who developed respiratory distress secondary to a left-sided diaphragmatic hernia. At 8 h of age an umbilical artery catheter was inserted with the position of Address offprint requests to: Dr. Thomas J. Starc, Department of Pediatrics, Division of Pediatric Cardiology, Columbia University, 630 West 168th Street, New York, NY 10032, USA
the catheter tip corresponding to the level of 10th thoracic vertebral body. The diaphragmatic hernia was successfully repaired at 12 h of age and the umbilical catheter was removed at 4 days of age. At 1 week of age the infant developed a new episode of respiratory distress. Physical examination at that time revealed a systolic blood pressure of 80 mmHg in the right arm and 30 mmHg in the right leg. The infant had a gallop rhythm, poor perfusion of the lower extremities, and metabolic acidosis. Right upper extremity systolic blood pressure increased to 150 mmHg over the next 2 days accompanied by diminished pulses in the lower extremities. Abdominal ultrasound imaging revealed an echogenic focus consistent with an aortic thrombus at a site corresponding to the location of the tip of the previously removed umbilical artery catheter (Fig. 1). The patient was treated with ventilatory support and antibiotics for presumed bacterial sepsis. The hospital course was complicated by ascites, hepatic and renal failure, and fungal sepsis secondary to Candida albicans. Although symptoms of organ failure and sepsis resolved, the pressure gradient between the upper and lower extremities persisted. Ultrasound studies demonstrated resolution of the thrombus, however, progressive enlargement of the descending aorta was observed (Fig. 2). Two-dimensional echocardiography delineated a normal transverse and juxtaductal aorta with dilatation of the descending aorta. Doppler flow evaluation of the descending aorta, below the dilated segment, revealed diminished systolic and diastolic flow patterns. Magnetic resonance imaging revealed an aneurysm of the aorta above the origin of the celiac artery. At 3 months of age a saccular aneurysm of the thoracic aorta measuring approximately 10 x 10 x 2 mm was resected (Fig. 3). No thrombus was found in the aneurysm. Microscopically, there was an abrupt transition between the wall of the
34
Pediatric CardioIogy Vol. 13, No. 1, 1992
Fig. 1. Case I. Longitudinal scan through the thoracic aorta reveals an echogenic focus within the aorta in this 8-day-old baby. Fig. 2. Case I. Longitudinal scan through the same area 2 months later shows aneurysmal dilatation of the aorta. The echogenic focus is no longer visible.
Fig. 3. Case l. The resected aorta at 3 months has been opened lengthwise and the walls laid out flat. The mouth of the aneurysm (arlwws) is large but does not involve the entire circumference of the aorta.
normal aorta and the wall of the aneurysm (Fig, 4). The inner wall of the aneurysm was composed of loose mesenchymal tissue, whereas the outer wall was composed of a thin layer of fibromuscular tissue and did not contain stainable elastic fibers. There were small loci of inflammation in the wall of the aneurysm, consisting predominately of eosinophils, lymphocytes, and macrophages and very few neutrophils. The macrophages contained hemosiderin pigment. Aortic reconstruction was accomplished using an 8-ram Gore-Tex graft. Upper extremity hypertensi ~n resolved after surgery and the infant remains normotensive after 18 months of observation.
Case 2 A 4-year-old boy presented with hypertension and clinical signs of coarctation of the aorta. Blood pressure in each of his arms was 140/82 mmHg. Further examination demonstrated decreased systolic blood pressure in the legs (90 mmHg), as well as a harsh systolic murmur over the lower thoracic paravertebral area. His past history revealed that at 2 years of age he had surgical removal of a thoracic neuroblastoma located in the left paraspinal area. During excision of the tumor mass, which was intimately adherent to the aorta, the aorta was entered and repaired. Doppler echocardiography demonstrated diminished blood flow in the descending aorta and magnetic resonance imaging demonstrated a narrowed segment of the aorta in the region
of the lower thoracic spine (Fig. 5). At 5 years of age, the blood pressure in his upper extremities decreased slightly to 125/80, while the pressure in his legs has remained unchanged. Close observation of the blood pressure gradient between the upper and lower extremities is being maintained in anticipation of eventual correction of the coarctation, either by balloon angioplasty or surgical repair.
Discussion
Signs and symptoms of coarctation of the aorta may occur after trauma to the vessel walt. In the first patient the appearance of symptoms consistent with a coarctation of the aorta was temporally related to the umbilical artery catheterization, aortic thrombosis, and fungal sepsis. The second patient developed a coarctation of the aorta after surgical aortotomy. Although coarctation of the aorta is usually caused by a congenital narrowing of the aorta, an acquired coarctation of the aorta is a known complication of several vascular disorders including Takayasu's disease [7], intimal fibromuscular dysplasia [5], and neurofibromatosis [i]. Even more rarely, an acquired coarctation has been documented after injury to the aorta due Io radiation [9], infection [10], aortic thrombosis [4, l l], and stab wound [8]. The first patient had an aortic thrombus and later developed an aortic aneurysm. The hemosiderin-laden macrophages in the wall of the resected aneurysm probably represent residue of the thrombus. Aortic thrombosis is a well-recognized complication of umbilical artery catheterization [6, 11] and has even been reported to occur spontaneously in the newborn [4]. Symptoms may mimic those of a congenital coarctation of the aorta and include hypertension in the upper extremities and absent pulses below the level of the thrombus. In our patient, upper extremity hypertension and diminished
Starc et al.: Acquired Coarctation of tl~e Aorta
35
i ii iiii~il
~!!1%;i
i?!ii'i!i!)!i
Fig. 4. Case I. The parallel arrangement of the multiple tayers of wavy elastic tissue fibers in the wall of the normal aorta is illustrated at the right of the photomicrograph. In contrast, the walt of the aneurysm seen on the left side of the photomicrograph contains no elastic tissue, (yon Gieson elastic tissue stain; original magnification, x 60). Fig. 5. Case 2. Saggital Tl-weighted magnetic resonance image in this 4-year-old boy, 2 years after removal of a thoracic neuroblastoma, demonstrates the narrowing of the aorta in the region of the lower thoracic spine.
lower extremity pulses persisted until surgical repair of the aortic aneurysm, despite echocardiographic resolution of the thrombus in the descending aorta. An aortic aneurysm is a rare sequela of umbilical artery catheterization. It is speculated that damage to the endothelium results in aneurysm formation near the site of the tip of the catheter [15]. The clinical course is usually complicated by sepsis and is associated with high morbidity and mortality rates. Inflammation in the wall of the resected aneurysm in our patient was not marked, but is consistent with the appearance of a mycotic aneurysm 3 months after formation. Gram and silver stains failed to identify bacteria or fungi, respectively, in
the resected aneurysm. In addition to the patient described in this report, at least one other neonate with an infected aneurysm, who developed a pressure gradient between the upper and lower extremities, has been described [2]. However, the actual incidence of a coarctation-like syndrome in infants with an infected aneurysm remains unknown, since blood pressures are often not described in reports of this condition. Although aneurysms complicating congenital coarctation of the aorta have been reported, they are rare and usually occur in older children or young adults [12]. The existence of both an underlying congenital coarctation of the aorta and a superimposed aneurysm at the site of an indwelling um-
Pediatric Cardiology Vol. 13, No. t, 1992
36
bilical artery catheter has been described in one infant [13]. This led those authors to recommend that umbilical catheters be avoided in patients with known anomalies of the aortic arch. Since the aortic arch was normal in our patient, we suspect that the aneurysm and blood pressure differential were secondary to infection and trauma from the umbilical artery catheter, rather than secondary to a congenital anomaly of the aorta. As demonstrated by the second patient, surgical trauma to the descending thoracic aorta may also lead to coarctation. One adult who developed a coarctation of the aorta after a knife wound has been previously described [8]. In such a patient the mechanism of coarctation is presumed to be secondary to scar tissue formation at the site of the repair. Recent advances in noninvasive ultrasonographic imaging techniques allow detailed examination of the thoracic and abdominal aorta [3, 14]. Magnetic resonance imaging is also extremely valuable in the evaluation of vascular structures. Abnormalities of the vessels, as well as their displacement and destruction by surrounding pathologic processes, are readily apparent on TI-weighted images. In addition, the ability to image in multiple anatomical planes aids in the diagnosis. Ultrasonography and magnetic resonance imaging are noninvasive and involve no radiation. With further experience, use of these modalities may replace invasive procedures, such as aortic angiography, in the diagnosis of many aortic lesions. In summary, we recommend that patients who have interventional damage to the aorta be periodically examined for the appearance of a coarctation. Careful blood pressure measurements in the upper extremity remain of critical importance in the diagnosis of this lesion, in addition to observations of lower extremity pulse and pressure. In the presence of a persistant blood pressure gradient between the upper and lower extremities, the entire aorta should be examined by specialized techniques, such as ultrasonography and magnetic resonance imaging.
References 1. Bloor K, Williams RT (1963) Neurofibromatosis and coarctation of the abdominal aorta with renal artery involvement. Br J Surg 50:811-813 2. Drucker DEM, Greenfield LJ, Ehrlich F, Salzberg AM (1986) Aorto-iliac aneurysms following umbilical artery catheterization. J Pediatr Surg 21:725-730 3. Gaffney JW, Bierman FZ, Donnelly CM, Sutton M, Piomelli S, Gersony WM (1988) Cardiovascular adaptations of transfusion/chelation therapy of homozygote sickle cell anemia. Am J Cardiol 62:121-125 4. Hamilton RM~ Penkoske PA, Byrne P, Duncan NF (1988) Spontaneous aortic thrombosis in a neonate presenting as coarctation. Ann Thorac Sm'g 45:564-565 5. Keech AC, Westlake GW, Wallis PL, Hamer AWF (1988) An acquired case of aortic coarctation. Am Heart J 115:1328-1332 6. LeBlanc JG, Culham JAG, Chan K-W, Patterson MW, Tipple M, Sandor GG (1986) Treatment of grafts and major vessel thrombosis with low-dose streptokinase in children. Ann Thorac Surg, 41:630-635 7. McKusick VA (1962) A form of vascular disease relatively frequent in the Orient. Am Heart J 63:57-64 8. Newby JP, Gesink MH, Newman MM (1966) Post-traumatic acquired coarctation of the descending thoracic aorta. J Thorac Cardiovasc Sur L, 51:883-886 9. Ormerod LP (1976) Acquired coarctation of the aorta--Long term complication of radiation. Br Med J 2:977 10. Reidemeister JC, Zerkowski HR, Rohm N, Machado JLB (1984) Acquired aortic coarctation due to posttuberculotic gibbous formation. Thomc Cardiovasc Surg 32:54-56 11. Rodriguez M, Sosenko l (1989) Catheter-induced aortic thrombus masquerading as coarctation of the aorta. Clin Pediatr 28:581-584 12. Schneider JA, Rheuban KS, Crosby IK (1979) Rupture of postcoarctation mycotic aneurysms of the aorta. Ann Thorac Surg 27:185-190 13. Spangler JG, Kleinberg F, Fulton RE, Barnhorst DA, Ritter DG (1977) False aneurysm of the descending aorta. A complication of umbilical artery catheterization. Am J Dis" Child 131:1258-1259 14. Starc R J, Krongrad E, Bierman FZ (1989) Two-dimensional echocardiography and Doppler findings in cerebral arteriovenous malformation. Am J Cardiol 64:252-254 15. Thompson TR, Tilleli J, Johnson DE, Britt W, L'Heureux P, Williams H, Jarvis C, Burke BA (1980) Umbilical artery catheterization complicated by mycotic aortic aneurysm in neonates. Adv Pediatr 27:275-318
Pediatric Cardiology 9 Springer-VerlagNew York Inc. 1992
Case Reports Acquired Coarctation of the Aorta Thomas J. S t a r c , 1 Sara J. Abramson, 2 Fredrick Z. Bierman, 1 Joan A. Regan, 1 Anneliese L. Sitarz, 1 Eric A. Rose, 3 R. Peter Altman, 3 Margaret H. Collins, 4 and Sylvia P. Griffiths~ Departments of ~Pediatrics, -'Radiology, ~Surgery, and 4pathology, Columbia University, College of Physicians and Surgeons, New York, New York, USA
SUMMARY. Coarctation of the aorta is usually caused by a congenital narrowing of the aorta. This report describes two children who developed hypertension secondary to an acquired coarc l tation of the aorta. In one patient the coarctation was temporally related to umbilical artery catheterization and was associated with thrombosis and aneurysmal dilatation of the aorta. In the second patient, the coarctatiun occurred after surgical aortotomy during the removal of an intrathoracic neuroblastoma. Patients who have interventional damage to the aorta should be periodically examined for the appearance of a coarctation. Although an acquired coarctation of the aorta is an infrequent complication of invasive or surgical procedures, it should be identified since it represents a remediable cause of hypertension in children. KEY WORDS: Coarctation of the a o r t a - H y p e r t e n s i o n - Children
Coarctation of the aorta most commonly occurs because of a congenital narrowing of the aorta and is usually present at the time of birth. This report describes two children who developed an acquired coarctation of the aorta manifested by upper extremity hypertension and diminished femoral pulses. In the first patient the coarctation was associated with thrombosis and aneurysmal dilatation of the aorta which was temporally related to umbilical artery catheterization. In the second patient the acquired coarctation occurred after surgical aortotomy. Although an acquired coarctation is an infrequent complication of invasive or surgical procedures, it should be identified since it represents a remediable cause of hypertension in infants and children. Case Reports Case 1 The patient was a full-term infant who developed respiratory distress secondary to a left-sided diaphragmatic hernia. At 8 h of age an umbilical artery catheter was inserted with the position of Address offprint requests to: Dr. Thomas J. Starc, Department of Pediatrics, Division of Pediatric Cardiology, Columbia University, 630 West 168th Street, New York, NY 10032, USA
the catheter tip corresponding to the level of 10th thoracic vertebral body. The diaphragmatic hernia was successfully repaired at 12 h of age and the umbilical catheter was removed at 4 days of age. At 1 week of age the infant developed a new episode of respiratory distress. Physical examination at that time revealed a systolic blood pressure of 80 mmHg in the right arm and 30 mmHg in the right leg. The infant had a gallop rhythm, poor perfusion of the lower extremities, and metabolic acidosis. Right upper extremity systolic blood pressure increased to 150 mmHg over the next 2 days accompanied by diminished pulses in the lower extremities. Abdominal ultrasound imaging revealed an echogenic focus consistent with an aortic thrombus at a site corresponding to the location of the tip of the previously removed umbilical artery catheter (Fig. 1). The patient was treated with ventilatory support and antibiotics for presumed bacterial sepsis. The hospital course was complicated by ascites, hepatic and renal failure, and fungal sepsis secondary to Candida albicans. Although symptoms of organ failure and sepsis resolved, the pressure gradient between the upper and lower extremities persisted. Ultrasound studies demonstrated resolution of the thrombus, however, progressive enlargement of the descending aorta was observed (Fig. 2). Two-dimensional echocardiography delineated a normal transverse and juxtaductal aorta with dilatation of the descending aorta. Doppler flow evaluation of the descending aorta, below the dilated segment, revealed diminished systolic and diastolic flow patterns. Magnetic resonance imaging revealed an aneurysm of the aorta above the origin of the celiac artery. At 3 months of age a saccular aneurysm of the thoracic aorta measuring approximately 10 x 10 x 2 mm was resected (Fig. 3). No thrombus was found in the aneurysm. Microscopically, there was an abrupt transition between the wall of the
34
Pediatric CardioIogy Vol. 13, No. 1, 1992
Fig. 1. Case I. Longitudinal scan through the thoracic aorta reveals an echogenic focus within the aorta in this 8-day-old baby. Fig. 2. Case I. Longitudinal scan through the same area 2 months later shows aneurysmal dilatation of the aorta. The echogenic focus is no longer visible.
Fig. 3. Case l. The resected aorta at 3 months has been opened lengthwise and the walls laid out flat. The mouth of the aneurysm (arlwws) is large but does not involve the entire circumference of the aorta.
normal aorta and the wall of the aneurysm (Fig, 4). The inner wall of the aneurysm was composed of loose mesenchymal tissue, whereas the outer wall was composed of a thin layer of fibromuscular tissue and did not contain stainable elastic fibers. There were small loci of inflammation in the wall of the aneurysm, consisting predominately of eosinophils, lymphocytes, and macrophages and very few neutrophils. The macrophages contained hemosiderin pigment. Aortic reconstruction was accomplished using an 8-ram Gore-Tex graft. Upper extremity hypertensi ~n resolved after surgery and the infant remains normotensive after 18 months of observation.
Case 2 A 4-year-old boy presented with hypertension and clinical signs of coarctation of the aorta. Blood pressure in each of his arms was 140/82 mmHg. Further examination demonstrated decreased systolic blood pressure in the legs (90 mmHg), as well as a harsh systolic murmur over the lower thoracic paravertebral area. His past history revealed that at 2 years of age he had surgical removal of a thoracic neuroblastoma located in the left paraspinal area. During excision of the tumor mass, which was intimately adherent to the aorta, the aorta was entered and repaired. Doppler echocardiography demonstrated diminished blood flow in the descending aorta and magnetic resonance imaging demonstrated a narrowed segment of the aorta in the region
of the lower thoracic spine (Fig. 5). At 5 years of age, the blood pressure in his upper extremities decreased slightly to 125/80, while the pressure in his legs has remained unchanged. Close observation of the blood pressure gradient between the upper and lower extremities is being maintained in anticipation of eventual correction of the coarctation, either by balloon angioplasty or surgical repair.
Discussion
Signs and symptoms of coarctation of the aorta may occur after trauma to the vessel walt. In the first patient the appearance of symptoms consistent with a coarctation of the aorta was temporally related to the umbilical artery catheterization, aortic thrombosis, and fungal sepsis. The second patient developed a coarctation of the aorta after surgical aortotomy. Although coarctation of the aorta is usually caused by a congenital narrowing of the aorta, an acquired coarctation of the aorta is a known complication of several vascular disorders including Takayasu's disease [7], intimal fibromuscular dysplasia [5], and neurofibromatosis [i]. Even more rarely, an acquired coarctation has been documented after injury to the aorta due Io radiation [9], infection [10], aortic thrombosis [4, l l], and stab wound [8]. The first patient had an aortic thrombus and later developed an aortic aneurysm. The hemosiderin-laden macrophages in the wall of the resected aneurysm probably represent residue of the thrombus. Aortic thrombosis is a well-recognized complication of umbilical artery catheterization [6, 11] and has even been reported to occur spontaneously in the newborn [4]. Symptoms may mimic those of a congenital coarctation of the aorta and include hypertension in the upper extremities and absent pulses below the level of the thrombus. In our patient, upper extremity hypertension and diminished
Starc et al.: Acquired Coarctation of tl~e Aorta
35
i ii iiii~il
~!!1%;i
i?!ii'i!i!)!i
Fig. 4. Case I. The parallel arrangement of the multiple tayers of wavy elastic tissue fibers in the wall of the normal aorta is illustrated at the right of the photomicrograph. In contrast, the walt of the aneurysm seen on the left side of the photomicrograph contains no elastic tissue, (yon Gieson elastic tissue stain; original magnification, x 60). Fig. 5. Case 2. Saggital Tl-weighted magnetic resonance image in this 4-year-old boy, 2 years after removal of a thoracic neuroblastoma, demonstrates the narrowing of the aorta in the region of the lower thoracic spine.
lower extremity pulses persisted until surgical repair of the aortic aneurysm, despite echocardiographic resolution of the thrombus in the descending aorta. An aortic aneurysm is a rare sequela of umbilical artery catheterization. It is speculated that damage to the endothelium results in aneurysm formation near the site of the tip of the catheter [15]. The clinical course is usually complicated by sepsis and is associated with high morbidity and mortality rates. Inflammation in the wall of the resected aneurysm in our patient was not marked, but is consistent with the appearance of a mycotic aneurysm 3 months after formation. Gram and silver stains failed to identify bacteria or fungi, respectively, in
the resected aneurysm. In addition to the patient described in this report, at least one other neonate with an infected aneurysm, who developed a pressure gradient between the upper and lower extremities, has been described [2]. However, the actual incidence of a coarctation-like syndrome in infants with an infected aneurysm remains unknown, since blood pressures are often not described in reports of this condition. Although aneurysms complicating congenital coarctation of the aorta have been reported, they are rare and usually occur in older children or young adults [12]. The existence of both an underlying congenital coarctation of the aorta and a superimposed aneurysm at the site of an indwelling um-
Pediatric Cardiology Vol. 13, No. t, 1992
36
bilical artery catheter has been described in one infant [13]. This led those authors to recommend that umbilical catheters be avoided in patients with known anomalies of the aortic arch. Since the aortic arch was normal in our patient, we suspect that the aneurysm and blood pressure differential were secondary to infection and trauma from the umbilical artery catheter, rather than secondary to a congenital anomaly of the aorta. As demonstrated by the second patient, surgical trauma to the descending thoracic aorta may also lead to coarctation. One adult who developed a coarctation of the aorta after a knife wound has been previously described [8]. In such a patient the mechanism of coarctation is presumed to be secondary to scar tissue formation at the site of the repair. Recent advances in noninvasive ultrasonographic imaging techniques allow detailed examination of the thoracic and abdominal aorta [3, 14]. Magnetic resonance imaging is also extremely valuable in the evaluation of vascular structures. Abnormalities of the vessels, as well as their displacement and destruction by surrounding pathologic processes, are readily apparent on TI-weighted images. In addition, the ability to image in multiple anatomical planes aids in the diagnosis. Ultrasonography and magnetic resonance imaging are noninvasive and involve no radiation. With further experience, use of these modalities may replace invasive procedures, such as aortic angiography, in the diagnosis of many aortic lesions. In summary, we recommend that patients who have interventional damage to the aorta be periodically examined for the appearance of a coarctation. Careful blood pressure measurements in the upper extremity remain of critical importance in the diagnosis of this lesion, in addition to observations of lower extremity pulse and pressure. In the presence of a persistant blood pressure gradient between the upper and lower extremities, the entire aorta should be examined by specialized techniques, such as ultrasonography and magnetic resonance imaging.
References 1. Bloor K, Williams RT (1963) Neurofibromatosis and coarctation of the abdominal aorta with renal artery involvement. Br J Surg 50:811-813 2. Drucker DEM, Greenfield LJ, Ehrlich F, Salzberg AM (1986) Aorto-iliac aneurysms following umbilical artery catheterization. J Pediatr Surg 21:725-730 3. Gaffney JW, Bierman FZ, Donnelly CM, Sutton M, Piomelli S, Gersony WM (1988) Cardiovascular adaptations of transfusion/chelation therapy of homozygote sickle cell anemia. Am J Cardiol 62:121-125 4. Hamilton RM~ Penkoske PA, Byrne P, Duncan NF (1988) Spontaneous aortic thrombosis in a neonate presenting as coarctation. Ann Thorac Sm'g 45:564-565 5. Keech AC, Westlake GW, Wallis PL, Hamer AWF (1988) An acquired case of aortic coarctation. Am Heart J 115:1328-1332 6. LeBlanc JG, Culham JAG, Chan K-W, Patterson MW, Tipple M, Sandor GG (1986) Treatment of grafts and major vessel thrombosis with low-dose streptokinase in children. Ann Thorac Surg, 41:630-635 7. McKusick VA (1962) A form of vascular disease relatively frequent in the Orient. Am Heart J 63:57-64 8. Newby JP, Gesink MH, Newman MM (1966) Post-traumatic acquired coarctation of the descending thoracic aorta. J Thorac Cardiovasc Sur L, 51:883-886 9. Ormerod LP (1976) Acquired coarctation of the aorta--Long term complication of radiation. Br Med J 2:977 10. Reidemeister JC, Zerkowski HR, Rohm N, Machado JLB (1984) Acquired aortic coarctation due to posttuberculotic gibbous formation. Thomc Cardiovasc Surg 32:54-56 11. Rodriguez M, Sosenko l (1989) Catheter-induced aortic thrombus masquerading as coarctation of the aorta. Clin Pediatr 28:581-584 12. Schneider JA, Rheuban KS, Crosby IK (1979) Rupture of postcoarctation mycotic aneurysms of the aorta. Ann Thorac Surg 27:185-190 13. Spangler JG, Kleinberg F, Fulton RE, Barnhorst DA, Ritter DG (1977) False aneurysm of the descending aorta. A complication of umbilical artery catheterization. Am J Dis" Child 131:1258-1259 14. Starc R J, Krongrad E, Bierman FZ (1989) Two-dimensional echocardiography and Doppler findings in cerebral arteriovenous malformation. Am J Cardiol 64:252-254 15. Thompson TR, Tilleli J, Johnson DE, Britt W, L'Heureux P, Williams H, Jarvis C, Burke BA (1980) Umbilical artery catheterization complicated by mycotic aortic aneurysm in neonates. Adv Pediatr 27:275-318
