Case Study Asian Cardiovascular & Thoracic Annals 2015, Vol. 23(5) 567–569 ß The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/0218492314522471 aan.sagepub.com
Pryce type I sequestration: No mosquito shooting Ramachandra Barik1, Amar Narayan Patnaik1, Amaresh Rao Malempati1,2 and Lalita Nemani1
Abstract We report a case of a 40-year-old woman with congenital dual arterial supply to an otherwise normal left lower lobe, causing hyperperfusion lung injury. In addition to near normal pulmonary arterial supply, the lower lobe of the left lung received a systemic arterial supply from the descending thoracic aorta. The patient was successfully managed by surgical ligation of the systemic arterial supply without lobectomy. We discuss when to defer lobectomy in Pryce type I sequestration.
Keywords Aorta, thoracic, bronchopulmonary sequestration, coronary angiography, lung, pulmonary artery
Introduction Systemic arterial supply to the lungs can be congenital or acquired. In the commonly reported congenital form of systemic arterial supply to the lower segment of the left lower lobe, there is abrupt dilatation followed by tapering of the systemic arterial supply from the descending thoracic aorta distal to the origin of the superior segmental artery.1–3 We report a rare case of dual arterial supply from the pulmonary and systemic arteries to the basal segments of the left lower lobe with a normal bronchial tree. The additional injurious systemic blood source from the descending thoracic aorta was removed. We discuss when to avoid lobectomy.
Case report A 40-year-old housewife presented with scanty recurrent hemoptysis over the past year. She denied having fever, chest pain, night sweats, shortness of breath, any anticoagulant use, or history of excessive sputum production, tuberculosis, or congenital heart disease. On physical examination, she appeared to be in good general condition. Clinical examination and routine laboratory investigations were normal. A chest radiograph in anterior posterior projection appeared normal. Echocardiography showed no chamber dilatation.
Bronchoscopy was normal. Cardiac catechization was normal except for a selective left pulmonary angiogram that showed reduced calibre and distribution of the left lower lobe pulmonary artery with intact venous drainage (Figure 1). A selective angiogram of the abnormal arterial supply to the left lobe was consistent with a computed tomography abdominal aortogram carried out subsequently (Figure 2). Computed tomography angiography of thoracoabdominal aorta was performed with a LightSpeed scanner using 0.625 mm collimation and 80 mL of nonionic intravenous contrast. The post-processing was undertaken using multiplanar reformation, maximum intensity projections, curved planar reformations, and volume rendering techniques. The aortic root, ascending aorta, arch and its branches are normal. The main pulmonary artery was mildly dilated (27 mm). The right pulmonary artery measured 18 mm. The right upper, middle, and lower lobar 1 Department of Cardiology, Nizam’s Institute of Medical Sciences, Hyderabad, Andhra Pradesh, India 2 Department of Cardiothoracic Surgery, Nizam’s Institute of Medical Sciences, Hyderabad, Andhra Pradesh, India
Corresponding author: Ramachandra Barik, DNB, Department of Cardiology, Nizam’s Institute of Medical Sciences, Hyderabad 500082, Andhra Pradesh, India. Email: [email protected]
Downloaded from aan.sagepub.com at U.A.E University on November 14, 2015
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Asian Cardiovascular & Thoracic Annals 23(5)
Figure 1. Selective left pulmonary angiogram showing a small left lower lobe pulmonary artery with scanty supply to the lower lobe. LPA: left pulmonary artery; RPA: right pulmonary artery.
Figure 2. Computed tomography revealing that the lower lobe segments are supplied by a large tortuous systemic artery arising from the left anterolateral wall of the descending aorta at D8 level.
arteries including their segmental and subsegmental divisions were normal. The left lower pulmonary artery measured 11 mm. Upper lobar, segmental, and subsegmental pulmonary arteries were normal. The lingular arteries were also normal. The descending pulmonary artery was small in calibre and supplied segment 6. The rest of the lower lobe segments were supplied by a large tortuous systemic arterial supply arising from the left anterolateral wall of the descending aorta at D8 level (Figure 2). It measured 7 mm in diameter at the ostial-proximal portion and showed diffuse ectasia and aneurysmal dilatation distally, measuring 18 mm. Focal thin calcified intimal plaques were noted in the dilated segment of this artery. There was no evidence of any intra- or extralobar sequestration. Partial volume loss of the left lower lobe was noted, with associated diffuse subtle ground-glass attenuation,
Figure 3. Identifying and ligating the systemic arterial supply from the descending thoracic aorta to the left lower lobe.
mild interlobar attenuation, and mild interlobular septal thickening. Normal pulmonary venous drainage of the lower lobe was observed. No evidence of arteriovenous fistula could be demonstrated in this study. The rest of the lung parenchyma and pleura in both lungs were normal. Although we obtained consent for a thoracoscopic lung biopsy to rule out hypertensive changes in the left lower lobe, we had no consent for device closure. Simple surgical ligation of the abnormal arterial connection and lung biopsy were undertaken via a left lateral thoracotomy. The left lower lobe looked hyper-perfused but there was no obvious scar or swelling. The bronchus was felt far into the distal part of the lobe. The pressure in the dilated portion of the abnormal artery (92/67 mm Hg) was close to the systemic pressure. We were surprised to see that after more than 1 h of clamping of the abnormal artery, there was no difference between the upper and lower lobe, indicating adequate pulmonary arterial supply during both deflation and inflation (Figure 3). The abnormal vessel was ligated and incised. The patient recovered well without any symptoms such as hemoptysis. On day 6, a chest radiograph showed an almost normal lung. Histopathology was nearly normal expect for hyperemia. A ventilation and perfusion scan was normal on the 10th day, the day of discharge.
Discussion Dual arterial supply to the left lower lobe of the lung is mainly congenital, and the usual additional source of blood supply is the descending thoracic aorta.2 Classic sequestration is defined as a non-functioning mass of lung tissue with no communication with the tracheobronchial tree and a single blood supply from the systemic circulation. However, the spectrum of sequestration includes various combinations of abnormal bronchial connection, arterial supply, and venous drainage. Anomalous systemic arterial supply to
Downloaded from aan.sagepub.com at U.A.E University on November 14, 2015
Barik et al.
569
normal segments of the lung has been classified as Pryce type I sequestration.3 Anomalous systemic arterial supply to the lungs may be simply an injurious addon to normal pulmonary blood flow. Classic findings include absence of the interlobar artery distal to the origin of the superior segmental artery, and abrupt tapering of the left lower lobar pulmonary artery distal to the origin of the superior segmental artery, with an aberrant systemic artery originating from the descending thoracic aorta. The arterial branches access the lung through the pulmonary hilum or inferior pulmonary ligament, and there are insignificant lung parenchyma findings such as ground-glass opacity and some volume loss,4,5 as seen in our case. Other sources may be collateral vessels from the celiac trunk or left subclavian artery in a case like this with a normal tracheobronchial tree and severe hypoplasia of the pulmonary artery.4,6 When the basal segments of the right lower lobe are involved, the systemic arterial supply may be from the descending thoracic aorta, abdominal aorta, or coeliac axis.7,8 There is a single case report of the peripheral parts of an otherwise normal left lung supplied by major systemic arteries arising from the left subclavian, internal mammary, and coeliac arteries. In our case, there was systemic arterial supply to the lung via a transpleural route. Clinically, anomalous systemic arterial supply to normal lungs is usually asymptomatic or minimally symptomatic. Frank hemoptysis and blood-stained sputum are the most frequent clinical symptoms. Other signs and symptoms of this disease are exertional dyspnea, a lower thoracic murmur, and congestive heart failure due to left heart overload. Chest radiography may show lung opacity, most commonly in the left retrocardiac area. Computed tomography of the thorax is the most useful modality to evaluate cases of suspected sequestration or anomalous systemic arterial supply to the lungs, because it clearly shows the bronchial and vascular anatomy of the lung. Computed tomography-angiography can clearly depict the origin of an aberrant systemic artery to the lungs. Bronchoscopy is helpful to exclude endobronchial causes of hemoptysis. A ventilation and perfusion scan also aids decision-making. Although most patients are minimally symptomatic, increased blood supply to the lungs over time can lead to congestive heart failure or hemoptysis. The decision to defer lobectomy is
derived mostly from noninvasive tests. Preoperative thoracoscopy is not always possible. Mosquito shooting is a metaphor: we do not shoot at a mosquito when it bites as it would injure the person but not the mosquito. In the same way, in the treatment of Pryce type I sequestration where the left lower part of lung is usually almost normal, there is no role of lobectomy; ligation of the aberrant artery is enough. An unnecessary lobectomy invites complications such as bronchopleural fistula and other related complications. In Pryce type I sequestration, when the diagnosis is well confirmed, lobectomy may be safely deferred. Funding This research received no specific grant from any funding agency in the public, commerical, or not-for-profit sectors.
Conflict of interest statement None declared.
References 1. Ando K, Maehara T, Adachi H, et al. Intralobar pulmonary sequestration supplied by an anomalous aneurysmal artery. Ann Thorac Surg 2012; 93: 319–322. 2. Ellis K. Fleischner lecture. Developmental abnormalities in the systemic blood supply to the lungs. ARJ Am J Roentgenol 1991; 156: 669–679. 3. Pryce DM. Lower accessory pulmonary artery with intralobar sequestration of lung: a report of seven cases. J Pathol Bacteriol 1946; 58: 457–467. 4. Yamanaka A, Hirai T, Fujimoto T, Hase M, Noguchi M and Konishi F. Anomalous systemic arterial supply to normal basal segments of the left lower lobe. Ann Thorac Surg 1999; 68: 332–338. 5. Kim TS, Lee KS, Im JG, Goo JM, Park JS and Kim JH. Systemic arterial supply to the normal basal segments of the left lower lobe: radiographic and CT findings in 11 patients. J Thorac Imaging 2002; 17: 34–39. 6. Irodi A, Cherian R, Keshava SN and James P. Dual arterial supply to normal lung: within the sequestration spectrum. Br J Radiol 2010; 83: e86–e89. 7. Litwin SB, Plauth WH Jr and Nadas AS. Anomalous systemic arterial supply to the lung causing pulmonary-artery hypertension. N Engl J Med 1970; 283: 1098–1099. 8. Flisak ME, Chandrasekar AJ, Marsan RE and Ali MM. Systemic arterialization of lung without sequestration. AMJ Am J Roentgenol 1982; 138: 751–753.
Downloaded from aan.sagepub.com at U.A.E University on November 14, 2015
Pryce type I sequestration: No mosquito shooting Ramachandra Barik1, Amar Narayan Patnaik1, Amaresh Rao Malempati1,2 and Lalita Nemani1
Abstract We report a case of a 40-year-old woman with congenital dual arterial supply to an otherwise normal left lower lobe, causing hyperperfusion lung injury. In addition to near normal pulmonary arterial supply, the lower lobe of the left lung received a systemic arterial supply from the descending thoracic aorta. The patient was successfully managed by surgical ligation of the systemic arterial supply without lobectomy. We discuss when to defer lobectomy in Pryce type I sequestration.
Keywords Aorta, thoracic, bronchopulmonary sequestration, coronary angiography, lung, pulmonary artery
Introduction Systemic arterial supply to the lungs can be congenital or acquired. In the commonly reported congenital form of systemic arterial supply to the lower segment of the left lower lobe, there is abrupt dilatation followed by tapering of the systemic arterial supply from the descending thoracic aorta distal to the origin of the superior segmental artery.1–3 We report a rare case of dual arterial supply from the pulmonary and systemic arteries to the basal segments of the left lower lobe with a normal bronchial tree. The additional injurious systemic blood source from the descending thoracic aorta was removed. We discuss when to avoid lobectomy.
Case report A 40-year-old housewife presented with scanty recurrent hemoptysis over the past year. She denied having fever, chest pain, night sweats, shortness of breath, any anticoagulant use, or history of excessive sputum production, tuberculosis, or congenital heart disease. On physical examination, she appeared to be in good general condition. Clinical examination and routine laboratory investigations were normal. A chest radiograph in anterior posterior projection appeared normal. Echocardiography showed no chamber dilatation.
Bronchoscopy was normal. Cardiac catechization was normal except for a selective left pulmonary angiogram that showed reduced calibre and distribution of the left lower lobe pulmonary artery with intact venous drainage (Figure 1). A selective angiogram of the abnormal arterial supply to the left lobe was consistent with a computed tomography abdominal aortogram carried out subsequently (Figure 2). Computed tomography angiography of thoracoabdominal aorta was performed with a LightSpeed scanner using 0.625 mm collimation and 80 mL of nonionic intravenous contrast. The post-processing was undertaken using multiplanar reformation, maximum intensity projections, curved planar reformations, and volume rendering techniques. The aortic root, ascending aorta, arch and its branches are normal. The main pulmonary artery was mildly dilated (27 mm). The right pulmonary artery measured 18 mm. The right upper, middle, and lower lobar 1 Department of Cardiology, Nizam’s Institute of Medical Sciences, Hyderabad, Andhra Pradesh, India 2 Department of Cardiothoracic Surgery, Nizam’s Institute of Medical Sciences, Hyderabad, Andhra Pradesh, India
Corresponding author: Ramachandra Barik, DNB, Department of Cardiology, Nizam’s Institute of Medical Sciences, Hyderabad 500082, Andhra Pradesh, India. Email: [email protected]
Downloaded from aan.sagepub.com at U.A.E University on November 14, 2015
568
Asian Cardiovascular & Thoracic Annals 23(5)
Figure 1. Selective left pulmonary angiogram showing a small left lower lobe pulmonary artery with scanty supply to the lower lobe. LPA: left pulmonary artery; RPA: right pulmonary artery.
Figure 2. Computed tomography revealing that the lower lobe segments are supplied by a large tortuous systemic artery arising from the left anterolateral wall of the descending aorta at D8 level.
arteries including their segmental and subsegmental divisions were normal. The left lower pulmonary artery measured 11 mm. Upper lobar, segmental, and subsegmental pulmonary arteries were normal. The lingular arteries were also normal. The descending pulmonary artery was small in calibre and supplied segment 6. The rest of the lower lobe segments were supplied by a large tortuous systemic arterial supply arising from the left anterolateral wall of the descending aorta at D8 level (Figure 2). It measured 7 mm in diameter at the ostial-proximal portion and showed diffuse ectasia and aneurysmal dilatation distally, measuring 18 mm. Focal thin calcified intimal plaques were noted in the dilated segment of this artery. There was no evidence of any intra- or extralobar sequestration. Partial volume loss of the left lower lobe was noted, with associated diffuse subtle ground-glass attenuation,
Figure 3. Identifying and ligating the systemic arterial supply from the descending thoracic aorta to the left lower lobe.
mild interlobar attenuation, and mild interlobular septal thickening. Normal pulmonary venous drainage of the lower lobe was observed. No evidence of arteriovenous fistula could be demonstrated in this study. The rest of the lung parenchyma and pleura in both lungs were normal. Although we obtained consent for a thoracoscopic lung biopsy to rule out hypertensive changes in the left lower lobe, we had no consent for device closure. Simple surgical ligation of the abnormal arterial connection and lung biopsy were undertaken via a left lateral thoracotomy. The left lower lobe looked hyper-perfused but there was no obvious scar or swelling. The bronchus was felt far into the distal part of the lobe. The pressure in the dilated portion of the abnormal artery (92/67 mm Hg) was close to the systemic pressure. We were surprised to see that after more than 1 h of clamping of the abnormal artery, there was no difference between the upper and lower lobe, indicating adequate pulmonary arterial supply during both deflation and inflation (Figure 3). The abnormal vessel was ligated and incised. The patient recovered well without any symptoms such as hemoptysis. On day 6, a chest radiograph showed an almost normal lung. Histopathology was nearly normal expect for hyperemia. A ventilation and perfusion scan was normal on the 10th day, the day of discharge.
Discussion Dual arterial supply to the left lower lobe of the lung is mainly congenital, and the usual additional source of blood supply is the descending thoracic aorta.2 Classic sequestration is defined as a non-functioning mass of lung tissue with no communication with the tracheobronchial tree and a single blood supply from the systemic circulation. However, the spectrum of sequestration includes various combinations of abnormal bronchial connection, arterial supply, and venous drainage. Anomalous systemic arterial supply to
Downloaded from aan.sagepub.com at U.A.E University on November 14, 2015
Barik et al.
569
normal segments of the lung has been classified as Pryce type I sequestration.3 Anomalous systemic arterial supply to the lungs may be simply an injurious addon to normal pulmonary blood flow. Classic findings include absence of the interlobar artery distal to the origin of the superior segmental artery, and abrupt tapering of the left lower lobar pulmonary artery distal to the origin of the superior segmental artery, with an aberrant systemic artery originating from the descending thoracic aorta. The arterial branches access the lung through the pulmonary hilum or inferior pulmonary ligament, and there are insignificant lung parenchyma findings such as ground-glass opacity and some volume loss,4,5 as seen in our case. Other sources may be collateral vessels from the celiac trunk or left subclavian artery in a case like this with a normal tracheobronchial tree and severe hypoplasia of the pulmonary artery.4,6 When the basal segments of the right lower lobe are involved, the systemic arterial supply may be from the descending thoracic aorta, abdominal aorta, or coeliac axis.7,8 There is a single case report of the peripheral parts of an otherwise normal left lung supplied by major systemic arteries arising from the left subclavian, internal mammary, and coeliac arteries. In our case, there was systemic arterial supply to the lung via a transpleural route. Clinically, anomalous systemic arterial supply to normal lungs is usually asymptomatic or minimally symptomatic. Frank hemoptysis and blood-stained sputum are the most frequent clinical symptoms. Other signs and symptoms of this disease are exertional dyspnea, a lower thoracic murmur, and congestive heart failure due to left heart overload. Chest radiography may show lung opacity, most commonly in the left retrocardiac area. Computed tomography of the thorax is the most useful modality to evaluate cases of suspected sequestration or anomalous systemic arterial supply to the lungs, because it clearly shows the bronchial and vascular anatomy of the lung. Computed tomography-angiography can clearly depict the origin of an aberrant systemic artery to the lungs. Bronchoscopy is helpful to exclude endobronchial causes of hemoptysis. A ventilation and perfusion scan also aids decision-making. Although most patients are minimally symptomatic, increased blood supply to the lungs over time can lead to congestive heart failure or hemoptysis. The decision to defer lobectomy is
derived mostly from noninvasive tests. Preoperative thoracoscopy is not always possible. Mosquito shooting is a metaphor: we do not shoot at a mosquito when it bites as it would injure the person but not the mosquito. In the same way, in the treatment of Pryce type I sequestration where the left lower part of lung is usually almost normal, there is no role of lobectomy; ligation of the aberrant artery is enough. An unnecessary lobectomy invites complications such as bronchopleural fistula and other related complications. In Pryce type I sequestration, when the diagnosis is well confirmed, lobectomy may be safely deferred. Funding This research received no specific grant from any funding agency in the public, commerical, or not-for-profit sectors.
Conflict of interest statement None declared.
References 1. Ando K, Maehara T, Adachi H, et al. Intralobar pulmonary sequestration supplied by an anomalous aneurysmal artery. Ann Thorac Surg 2012; 93: 319–322. 2. Ellis K. Fleischner lecture. Developmental abnormalities in the systemic blood supply to the lungs. ARJ Am J Roentgenol 1991; 156: 669–679. 3. Pryce DM. Lower accessory pulmonary artery with intralobar sequestration of lung: a report of seven cases. J Pathol Bacteriol 1946; 58: 457–467. 4. Yamanaka A, Hirai T, Fujimoto T, Hase M, Noguchi M and Konishi F. Anomalous systemic arterial supply to normal basal segments of the left lower lobe. Ann Thorac Surg 1999; 68: 332–338. 5. Kim TS, Lee KS, Im JG, Goo JM, Park JS and Kim JH. Systemic arterial supply to the normal basal segments of the left lower lobe: radiographic and CT findings in 11 patients. J Thorac Imaging 2002; 17: 34–39. 6. Irodi A, Cherian R, Keshava SN and James P. Dual arterial supply to normal lung: within the sequestration spectrum. Br J Radiol 2010; 83: e86–e89. 7. Litwin SB, Plauth WH Jr and Nadas AS. Anomalous systemic arterial supply to the lung causing pulmonary-artery hypertension. N Engl J Med 1970; 283: 1098–1099. 8. Flisak ME, Chandrasekar AJ, Marsan RE and Ali MM. Systemic arterialization of lung without sequestration. AMJ Am J Roentgenol 1982; 138: 751–753.
Downloaded from aan.sagepub.com at U.A.E University on November 14, 2015
