Ann Thorac Surg 1999;68:1416-1418
© 1999 The Society of Thoracic Surgeons
Case Reports
Scimitar syndrome with pulmonary arteriovenous fistulas
Jean Philippe Le Rochais, MDa,
Philippe Icard, MDa,
Sepideh Davani, MDb,
Driss Abouz, MDb,
Claude Evrard, MDa
a Service de Chirurgie Thoracique et Cardiovasculaire, CHU de Caen, Caen, France
b Service de Pneumologie, CHG de Lisieux, Lisieux, France
Address reprint requests to Dr Le Rochais, Service de Chirurgie Thoracique, CHU Côte de Nacre, 14033 Caen cedex, France
e-mail: lerochais-jp{at}chu-caen.fr
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Abstract
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Right abnormal pulmonary venous return into the inferior vena cava associated with abnormal fissure, dextrocardia, and systemic arterial supply of a variable degree, are the characteristics of the scimitar syndrome. We report on a patient in whom this rare syndrome was associated with pulmonary arteriovenous fistulas within the involved lung.
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Introduction
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The most characteristic sign of the scimitar syndrome is a right abnormal venous return into the inferior vena cava [1]. This syndrome also involves various inconsistent abnormalities of the right bronchial branching and segmentations, with systemic arterial supply of a variable degree [1–3]. The association with bronchopulmonary arteriovenous malformations is exceptional.
A 43-year-old man, without significant past medical history, was referred from another hospital to our department in February 1996 after a transient neurologic attack and weakness. A chest radiograph revealed several right inferior lung opacities. Computed tomography scan showed multiple intraparenchymal vascular malformations, localized in the mid-part of the right lung. There was also a cardiac dextroposition. Fiberoptic bronchoscopy was normal, except that the apical branch of the lower lobe was branching with the bronchus of the middle lobe. A pulmonary angiography showed a right pulmonary artery with a reduced caliber. Also, several arteriovenous dilatations were opacified, and the venous return drained into the inferior vena cava just below the diaphragm (Fig 1). An aortography demonstrated a large aberrant artery arising from the celiac trunk of the aorta, which supplied the inferior part of the lung (Fig 2). Respiratory function and blood gas analysis were normal. There was no sign of Rendu-Osler-Weber syndrome with hereditary hemorrhagic telangiectasia. Because of the importance of arteriovenous malformations with the transient neurologic attack, an exploratory thoracotomy was performed, showing a bilobed right lung, without fissure separating the lower lobe from the middle lobe. There were two aberrant arteries (one large and one small) arising from below the diaphragm, with a large satellite vein draining the lower part of the lung, whereas in normal anatomy, the middle part drained into the right superior vein. A right inferior and middle bilobectomy was performed. Postoperative recovery was uneventful. Histologic examination confirmed the diagnosis of scimitar syndrome with several arteriovenous fistulas, partially thrombosed.
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Fig 1. Pulmonary angiogram showing arteriovenous fistulas located in the inferior mid-part of the right lung. Note the abnormal pulmonary venous return into the inferior vena cava.
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Fig 2. Selective arteriogram illustrating the aberrant large artery supplying the involved lung arising from the celiac trunk.
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Comment
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The term dysmorphic lung has been introduced to describe any complex congenital malformation that involves both abnormal vascular morphology and disordered growth of the entire lung [4]. The major group within this definition of dysmorphic lung is the scimitar syndrome, which includes various degrees of hypoplastic malformed right lung with partial or total anomalous venous drainage into the inferior vena cava [1–3]. The incidence is probably 1 to 3 of 100,000 live births [2]. The abnormal venous return is the main component of the syndrome, and gives a characteristic abnormal radiographic shadow descending along the right cardiac border, which resembles a curved Turkish sword (ie, scimitar) [1]. However, as it appears in our patient, this radiologic sign can be hidden behind the dextrocardia [2]. The abnormal vein drains the entire lung, or only the lower lobe, the middle lobe, or both lobes. The upper portion of the lung drains normally into the left atrium, as does sometimes the middle lobe, such as in our patient. As demonstrated, there is also often a reduced size of the right pulmonary artery, and some degree of bronchial anomalies, with absence of fissures, abnormal bronchial connection, which may give an aspect of bronchial isomerism, and the right-side anatomy resembling the left one. The existence of an aberrant artery arising from the aorta or one of its side branches may mimic sequestration. However, because bronchopulmonary sequestration is per definition an area of nonfunctional lung parenchyma that has no connection with the bronchial system, this designation is not correct [5]. As stressed by Panicek and colleagues [4], pulmonary anomalies exist as a continuum, often frustrating our attempts to classify them. Many patients are asymptomatic and the condition is often discovered accidentally. Symptomatic patients are often infants with marked left-to-right shunt and associated severe congenital heart disease. In such patients, results of reimplantation of the anomalous vein have been disappointing [2]; resection of the abnormal lung when feasible, being the treatment of choice [3]. Preoperative morphologic examinations are helpful by depicting the feeding vessels and other associated findings [6]. Pulmonary arteriovenous malformations are often associated with Rendu-Osler-Weber syndrome [6]. They usually act as direct right-to-left shunts, resulting in fatigue, cyanosis, and polycythemia, with a risk of neurologic manifestations [6]. In our patient, the abnormal venous return in the inferior vena cava created a right-to-right shunt; a normal venous return would stop any embolus coming from the inferior part of the lung. Because in our patient, the middle part of the lung was normally drained into the left atrium through the right superior vein, we believe that an embolus had caused the neurologic event. Moreover, as the right lobe was supplied by systemic arterial blood, the patient also had a left-to-right shunt. This association of pulmonary arteriovenous fistulas with a scimitar syndrome is difficult to understand but suggests that all abnormalities occurred at a similar time early in pulmonary embryologic development.
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References
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Neill C.A., Ferencz C., Sabiston D.C., Sheldon H. The familial occurrence of hypoplastic right lung with systemic arterial supply and venous drainage "scimitar syndrome.". Bull Johns Hopkins Hosp 1960;107:1-20.[Medline]
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Dupuis C., Charaf L.A.C., Brevière G.M., Abou P., Rémy-Jardin M., Helmius G. The "adult" form of the scimitar syndrome. Am J Cardiol 1992;70:502-507.[Medline]
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Thibault C., Perrault L.P., Delisle G., et al. Lobectomy in the treatment of the scimitar syndrome. Ann Thorac Surg 1995;59:220-221.[Abstract/Free Full Text]
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Panicek D.M., Heitzman E.R., Randall P.A., et al. The continuum of pulmonary developmental anomalies. Radiographics 1987;7:747-772.[Abstract]
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Savic B., Birtel F.J., Tholen W., Funke H.D., Knoche R. Lung sequestration. Thorax 1979;34:96-101.[Abstract/Free Full Text]
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Keslar P., Newman B., Oh Sang K. Radiographic manifestations of the anomalies of the lung. Radiol Clin North Am 1991;29:255-270.[Medline]
Accepted for publication March 30, 1999.
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Abstract
Introduction
