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Bronchial Artery Embolization: Anatomy and Technique
Bronchial Artery Embolization: Anatomy and Technique Jean-Pierre Pelage, PhD, MD Transcatheter embolization has become a first-line therapy in the management of hemoptysis. Knowledge of the arterial anatomy and variants is the key to safe and successful procedure. Tech Vasc Interventional Rad 10:274-275 © 2007 Elsevier Inc. All rights reserved. KEYWORDS bronchial, artery-arterial, embolization-hemoptysis-spiral CT-pulmonary, artery
H
emoptysis is the expectoration of blood or bloodstained sputum from the lungs or airways (bronchi, larynx, trachea). Massive hemoptysis, defined as hemoptysis exceeding 200 to 600 mL within a period of 24 hours or less, is a medical emergency since the reported mortality rate can be as high as 75%.1 Blood traversing the lungs can originate from low pressure and low resistance pulmonary arteries accounting for 99% of the cardiac output and high-pressure and high-resistance bronchial arteries accounting for 1% of the cardiac output.1,2 The pulmonary arteries supply exclusively the pulmonary capillary bed, whereas the bronchial arteries provide the nutritive blood supply to the airways, the lymph nodes, visceral pleura, and other portions of the mediastinum. There are normal anastomoses between both circulations but any abnormal process creating obstruction, compression, or destruction of the pulmonary capillary bed may induce a compensatory development of these anastomoses.2 Thus, despite the quantitatively smaller contribution of the bronchial circulation to the normal pulmonary blood flow, the bronchial arteries are generally a more important source of bleeding than the pulmonary circulation (90% versus 10% approximately). In addition to being perfused at a high pressure, the bronchial arteries supply blood to lesions within the airways and may become hyperplastic and tortuous, potentially causing massive hemoptysis.2 In the presence of pleural thickening, nonbronchial systemic feeder arteries may develop through the pleural surface and become enlarged as a result of the inflammatory pulmonary process. Many researchers currently suggest that contrast-enhanced spiral computed tomography (CT) should be performed before bronchoscopy, particularly in the case of massive hemoptysis.3,4 CT may demonstrate the site and the Department of Radiology, Hôpital Ambroise Paré, Université Paris Ile-deFrance Ouest 9, Boulogne-Billancourt, France. Address reprint requests to Jean-Pierre Pelage, PhD, MD, Department of Radiology, Hôpital Ambroise Paré, Université Paris Ile-de-France Ouest 9, avenue Charles De Gaulle, F 92104 Boulogne-Billancourt, France. E-mail: [email protected].
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1089-2516/07/$-see front matter © 2007 Elsevier Inc. All rights reserved. doi:10.1053/j.tvir.2008.03.005
cause of bleeding. Multidetector CT allows rapid scanning throughout the thorax, multiplanar reconstructions without loss of z-axis information owing to near isotropic voxel size, and acquisition of various three-dimensional images.4 Analysis of both lung parenchyma and visualization of the bronchial and nonbronchial systemic feeder vessels and pulmonary artery branches can be achieved simultaneously when iodinated-contrast material is administered. Multiplanar (parallel to the axis of the bronchial arteries) and maximum intensity projection (MIP) reconstructions are helpful to identify the origin and course of the bronchial and nonbronchial enlarged systemic arteries.3,4 The sensitivity and accuracy of MDCT in the depiction of nonbronchial arteries is as high as 80% and may be particularly helpful before embolization.3,4 Arteriography has been a major addition to the diagnostic and therapeutic armamenterium for the management of hemoptysis.5 Since the majority of massive bleeds arise from the bronchial circulation, bronchial arteriography has a higher yield than pulmonary angiography. The pulmonary arterial circulation is the source of bleeding in fewer than 10% of patients with massive hemoptysis. Systemic arteriography is performed with a digital substraction technique by using a transfemoral approach and with the Seldinger technique. The most commonly used catheters to select the bronchial arteries are Cobra, Mikaelson, Simmons, or Judkins right catheters. For safe catheterization and embolization of the bronchial artery, the use of 2.4/2.8-French microcatheters is recommended. The usual angiographic criteria for arteries causing hemoptysis include enlarged and tortuous bronchial or nonbronchial arteries, neovascularity or hypervascularity, antegrade or retrograde shunting to the pulmonary artery, extravasation of contrast material, or bronchial artery aneurysms. Both bronchial and nonbronchial transpleural systemic arteries should be investigated.6 Nonbronchial arteries frequently involved in recurrent bleeding include intercostal, inferior phrenic, subclavian, axillary, and internal mammary arteries. There is also a high incidence of bleeding from non-
Bronchial artery embolization bronchial systemic collateral vessels among patients who have undergone a previous bronchial artery embolization procedure.6 Therefore, persistence of bleeding after a technically good embolization suggests an origin other than those previously occluded.6 Bronchial arteries of anomalous origin or nonbronchial arteries initially not evaluated or missed, and the pulmonary circulation, should then be studied.2,4,6 Jacques Remy and coworkers reported for the first time successful bronchial artery embolization in four patients with massive or repeated hemoptysis in 1973.5 In 90% of cases, the source of hemoptysis is the bronchial circulation. Knowledge of the bronchial artery anatomy, together with an understanding of the pathophysiologic features of massive hemoptysis, are essential for planning and performing arterial embolization in affected patients.2 According to Cauldwell and coworkers, the bronchial arteries originate with a few exceptions from the proximal portion of the descending thoracic aorta.2 The right bronchial artery arises from the lateral or dorsolateral aspect of the aorta, most frequently in a common trunk with an intercostal artery (intercostobronchial artery).2 The left bronchial artery usually originates from the anterior aspect of the thoracic aorta or the concavity of the aortic arch.2 A left-right bronchial artery may also be seen.2 Radiologists should be alerted to the possible presence of anomalous bronchial arteries, especially when significant bronchial artery supply to areas of abnormal pulmonary parenchyma is not demonstrated at a catheter search or aortography of the descending aorta. Thus, bronchial arteries of anomalous origin may arise from the convex surface of the aortic arch from the supra-aortic arteries.4,7 Nonbronchial systemic circulation of the lung may also cause hemoptysis. Finally, the arteries of the pulmonary ligament may also be a rare source of hemoptysis.2 Special attention should be paid to identification of a spinal artery particularly when catheterizing a right intercostobronchial artery. Other arteries to be identified to reduce the risks of ischemic complications are esophageal, tracheal, pericardiophrenic, and coronary branches.4 Various embolization materials have been used to perform bronchial artery embolization. The use of resorbable pledgets of gelatin sponge, nonspherical or spherical polyvinyl alcohol particles, tris-acryl gelatin microspheres, acrylic glue, and steel coils has been already reported.5-9 When microcatheters are used, nonspherical polyvinyl alcohol particles or calibrated microspheres should be favored. The optimal size depends on the underlying condition. If microspheres larger than 500 m are usually the first choice for bronchial artery embolization, larger particles (⬎700 m) are recommended
275 in case of large bronchial artery-to-pulmonary artery antegrade shunts to prevent nontarget embolization. Since recurrence of bleeding is reported in up to 30% of patients, it is usually advised not to use coils for bronchial artery embolization. Coils occlude the bronchial arteries proximally and may therefore prevent future re-embolization. Technical failure of attempted embolization can be observed in about 10 to 20% of cases because of catheterization failure, catheter instability, or visualization of dangerous branches such as the anterior spinal artery. Embolization is able to achieve an immediate control of hemoptysis in 70 to 95% of cases, confirming that systemic circulation is the primary source of bleeding in hemoptysis.5-9 Complications are rare in experienced hands but major complications have already been reported. Spinal cord injury related to invisible anastomotic connections between the bronchial circulation and the anterior spinal artery have been reported.10 Careful analysis of the angiographic images particularly to identify a spinal artery when injecting into a right intercostobronchial artery, and the systematic use of microcatheters may reduce the rate of this complication.
References 1. Cahill BC, Ingbar DH: Massive hemoptysis: assessment and management. Clin Chest Med 15:147-167, 1994 2. Cauldwell E, Siekert R, Lininger, et al: The bronchial arteries: an anatomic study in 150 human cadavers. Surg Gynecol Obstet 86:395-412, 1948 3. Revel MP, Fournier LS, Hennebicque AS, et al: Can CT replace bronchoscopy in the detection of the site and cause of bleeding in patients with large or massive hemoptysis. AJR Am J Roentgenol 179:12171224, 2002 4. Remy-Jardin M, Bouaziz N, Dumont P, et al: Bronchial and nonbronchial systemic arteries at multi-detector row CT angiography: comparison with conventional angiography. Radiology 233:741-749, 2004 5. Remy J, Voisin C, Ribet M, et al: Treatment, by embolization, of severe or repeated hemoptysis associated with systemic hypervascularization [in French]. Presse Med 2:2060, 1973 6. Mal H, Rullon I, Mellot F, et al: Immediate and long-term results of bronchial artery embolization for life-threatening hemoptysis. Chest 115:996-1001, 1999 7. Do KH, Goo JM, Im JG, et al: Systemic arterial supply to the lungs in adults: spiral CT findings. Radiographics 21:387-402, 2001 8. Tanaka N, Yamakado K, Murashima S, et al: Superselective bronchial artery embolization for hemoptysis with a coaxial microcatheter system. J Vasc Interv Radiol 8:65-70, 1997 9. White RI Jr: Bronchial artery embolotherapy for control of acute hemoptysis: analysis of outcome. Chest 115:912-915, 1999 10. Miller FJ, Mineau DE: Transcatheter arterial embolization: major complications and their prevention. Cardiovasc Intervent Radiol 6:141149, 1983
H
emoptysis is the expectoration of blood or bloodstained sputum from the lungs or airways (bronchi, larynx, trachea). Massive hemoptysis, defined as hemoptysis exceeding 200 to 600 mL within a period of 24 hours or less, is a medical emergency since the reported mortality rate can be as high as 75%.1 Blood traversing the lungs can originate from low pressure and low resistance pulmonary arteries accounting for 99% of the cardiac output and high-pressure and high-resistance bronchial arteries accounting for 1% of the cardiac output.1,2 The pulmonary arteries supply exclusively the pulmonary capillary bed, whereas the bronchial arteries provide the nutritive blood supply to the airways, the lymph nodes, visceral pleura, and other portions of the mediastinum. There are normal anastomoses between both circulations but any abnormal process creating obstruction, compression, or destruction of the pulmonary capillary bed may induce a compensatory development of these anastomoses.2 Thus, despite the quantitatively smaller contribution of the bronchial circulation to the normal pulmonary blood flow, the bronchial arteries are generally a more important source of bleeding than the pulmonary circulation (90% versus 10% approximately). In addition to being perfused at a high pressure, the bronchial arteries supply blood to lesions within the airways and may become hyperplastic and tortuous, potentially causing massive hemoptysis.2 In the presence of pleural thickening, nonbronchial systemic feeder arteries may develop through the pleural surface and become enlarged as a result of the inflammatory pulmonary process. Many researchers currently suggest that contrast-enhanced spiral computed tomography (CT) should be performed before bronchoscopy, particularly in the case of massive hemoptysis.3,4 CT may demonstrate the site and the Department of Radiology, Hôpital Ambroise Paré, Université Paris Ile-deFrance Ouest 9, Boulogne-Billancourt, France. Address reprint requests to Jean-Pierre Pelage, PhD, MD, Department of Radiology, Hôpital Ambroise Paré, Université Paris Ile-de-France Ouest 9, avenue Charles De Gaulle, F 92104 Boulogne-Billancourt, France. E-mail: [email protected].
274
1089-2516/07/$-see front matter © 2007 Elsevier Inc. All rights reserved. doi:10.1053/j.tvir.2008.03.005
cause of bleeding. Multidetector CT allows rapid scanning throughout the thorax, multiplanar reconstructions without loss of z-axis information owing to near isotropic voxel size, and acquisition of various three-dimensional images.4 Analysis of both lung parenchyma and visualization of the bronchial and nonbronchial systemic feeder vessels and pulmonary artery branches can be achieved simultaneously when iodinated-contrast material is administered. Multiplanar (parallel to the axis of the bronchial arteries) and maximum intensity projection (MIP) reconstructions are helpful to identify the origin and course of the bronchial and nonbronchial enlarged systemic arteries.3,4 The sensitivity and accuracy of MDCT in the depiction of nonbronchial arteries is as high as 80% and may be particularly helpful before embolization.3,4 Arteriography has been a major addition to the diagnostic and therapeutic armamenterium for the management of hemoptysis.5 Since the majority of massive bleeds arise from the bronchial circulation, bronchial arteriography has a higher yield than pulmonary angiography. The pulmonary arterial circulation is the source of bleeding in fewer than 10% of patients with massive hemoptysis. Systemic arteriography is performed with a digital substraction technique by using a transfemoral approach and with the Seldinger technique. The most commonly used catheters to select the bronchial arteries are Cobra, Mikaelson, Simmons, or Judkins right catheters. For safe catheterization and embolization of the bronchial artery, the use of 2.4/2.8-French microcatheters is recommended. The usual angiographic criteria for arteries causing hemoptysis include enlarged and tortuous bronchial or nonbronchial arteries, neovascularity or hypervascularity, antegrade or retrograde shunting to the pulmonary artery, extravasation of contrast material, or bronchial artery aneurysms. Both bronchial and nonbronchial transpleural systemic arteries should be investigated.6 Nonbronchial arteries frequently involved in recurrent bleeding include intercostal, inferior phrenic, subclavian, axillary, and internal mammary arteries. There is also a high incidence of bleeding from non-
Bronchial artery embolization bronchial systemic collateral vessels among patients who have undergone a previous bronchial artery embolization procedure.6 Therefore, persistence of bleeding after a technically good embolization suggests an origin other than those previously occluded.6 Bronchial arteries of anomalous origin or nonbronchial arteries initially not evaluated or missed, and the pulmonary circulation, should then be studied.2,4,6 Jacques Remy and coworkers reported for the first time successful bronchial artery embolization in four patients with massive or repeated hemoptysis in 1973.5 In 90% of cases, the source of hemoptysis is the bronchial circulation. Knowledge of the bronchial artery anatomy, together with an understanding of the pathophysiologic features of massive hemoptysis, are essential for planning and performing arterial embolization in affected patients.2 According to Cauldwell and coworkers, the bronchial arteries originate with a few exceptions from the proximal portion of the descending thoracic aorta.2 The right bronchial artery arises from the lateral or dorsolateral aspect of the aorta, most frequently in a common trunk with an intercostal artery (intercostobronchial artery).2 The left bronchial artery usually originates from the anterior aspect of the thoracic aorta or the concavity of the aortic arch.2 A left-right bronchial artery may also be seen.2 Radiologists should be alerted to the possible presence of anomalous bronchial arteries, especially when significant bronchial artery supply to areas of abnormal pulmonary parenchyma is not demonstrated at a catheter search or aortography of the descending aorta. Thus, bronchial arteries of anomalous origin may arise from the convex surface of the aortic arch from the supra-aortic arteries.4,7 Nonbronchial systemic circulation of the lung may also cause hemoptysis. Finally, the arteries of the pulmonary ligament may also be a rare source of hemoptysis.2 Special attention should be paid to identification of a spinal artery particularly when catheterizing a right intercostobronchial artery. Other arteries to be identified to reduce the risks of ischemic complications are esophageal, tracheal, pericardiophrenic, and coronary branches.4 Various embolization materials have been used to perform bronchial artery embolization. The use of resorbable pledgets of gelatin sponge, nonspherical or spherical polyvinyl alcohol particles, tris-acryl gelatin microspheres, acrylic glue, and steel coils has been already reported.5-9 When microcatheters are used, nonspherical polyvinyl alcohol particles or calibrated microspheres should be favored. The optimal size depends on the underlying condition. If microspheres larger than 500 m are usually the first choice for bronchial artery embolization, larger particles (⬎700 m) are recommended
275 in case of large bronchial artery-to-pulmonary artery antegrade shunts to prevent nontarget embolization. Since recurrence of bleeding is reported in up to 30% of patients, it is usually advised not to use coils for bronchial artery embolization. Coils occlude the bronchial arteries proximally and may therefore prevent future re-embolization. Technical failure of attempted embolization can be observed in about 10 to 20% of cases because of catheterization failure, catheter instability, or visualization of dangerous branches such as the anterior spinal artery. Embolization is able to achieve an immediate control of hemoptysis in 70 to 95% of cases, confirming that systemic circulation is the primary source of bleeding in hemoptysis.5-9 Complications are rare in experienced hands but major complications have already been reported. Spinal cord injury related to invisible anastomotic connections between the bronchial circulation and the anterior spinal artery have been reported.10 Careful analysis of the angiographic images particularly to identify a spinal artery when injecting into a right intercostobronchial artery, and the systematic use of microcatheters may reduce the rate of this complication.
References 1. Cahill BC, Ingbar DH: Massive hemoptysis: assessment and management. Clin Chest Med 15:147-167, 1994 2. Cauldwell E, Siekert R, Lininger, et al: The bronchial arteries: an anatomic study in 150 human cadavers. Surg Gynecol Obstet 86:395-412, 1948 3. Revel MP, Fournier LS, Hennebicque AS, et al: Can CT replace bronchoscopy in the detection of the site and cause of bleeding in patients with large or massive hemoptysis. AJR Am J Roentgenol 179:12171224, 2002 4. Remy-Jardin M, Bouaziz N, Dumont P, et al: Bronchial and nonbronchial systemic arteries at multi-detector row CT angiography: comparison with conventional angiography. Radiology 233:741-749, 2004 5. Remy J, Voisin C, Ribet M, et al: Treatment, by embolization, of severe or repeated hemoptysis associated with systemic hypervascularization [in French]. Presse Med 2:2060, 1973 6. Mal H, Rullon I, Mellot F, et al: Immediate and long-term results of bronchial artery embolization for life-threatening hemoptysis. Chest 115:996-1001, 1999 7. Do KH, Goo JM, Im JG, et al: Systemic arterial supply to the lungs in adults: spiral CT findings. Radiographics 21:387-402, 2001 8. Tanaka N, Yamakado K, Murashima S, et al: Superselective bronchial artery embolization for hemoptysis with a coaxial microcatheter system. J Vasc Interv Radiol 8:65-70, 1997 9. White RI Jr: Bronchial artery embolotherapy for control of acute hemoptysis: analysis of outcome. Chest 115:912-915, 1999 10. Miller FJ, Mineau DE: Transcatheter arterial embolization: major complications and their prevention. Cardiovasc Intervent Radiol 6:141149, 1983