Intralobar Sequestration of the Lung Presenting Continuous Murmur—A Case Report
as a
D. Vaidiyanathan, M.D., D.M. K. Meenakshi, M.D., D.M. S. Elangovan, M.D., D.M. J. Jeyachandran, M.D. V. Chockalingam, M.D., D.M.
and A.
Tajamul Hussain, M.D.,
D.M.
MADRAS, INDIA
Abstract An eighteen-year-old asymptomatic woman with a continuous murmur, normal two-dimensional echocardiogram, and mild haziness of the left lower segment of the lung on chest x-ray was diagnosed to have sequestration based on the presence of a large anomalous systemic artery arising from the descending thoracic aorta supplying the lower lobe of the left lung. Normal bronchial connections with the rest of the lung on bronchoscopy and delayed dye clearance from the left lower lobe bronchioles on bronchogram indicated its intralobar nature. The cause of the continuous murmur was thought to be the large flow through the anomalous systemic artery. Introduction
Pulmonary sequestration is the term applied to a congenital malformation characterized by of embryonic lung tissue that derives its blood supply from an anomalous systemic artery. The formation of an accessory lung bud caudal to the normal lung bud in embryonic life is the cause of this anomaly. The anomalous systemic artery is due to the persistence of the communications between the dorsal aorta and the splanchnic vascular bed. an area
CASE REPORT An
eighteen-year-old asymptomatic woman, bom of a nonconsanguineous parentage, was referred for the evaluation of a continuous murmur over the chest. There was no cyanosis, the mean jugular venous pressure was normal, and the blood pressure was 150/70 mmHg and From the
Department of Cardiology,
Government General
Hospital, Madras,
India
610 Downloaded from ang.sagepub.com at FLORIDA INTERNATIONAL UNIV on July 6, 2015
611
The heart sounds were normal and there was a continuous murmur that was best heard in the lower left interscapular and infrascapular regions. Other systems were normal. The patient was subjected to detailed clinical examination, electrocardiogram (ECG), twodimensional echocardiography, Doppler, color flow Doppler imaging (CFDI), chest x-ray, barium swallow, meal and follow through, fibrooptic bronchoscopy, bronchography, and aortography. The ECG appeared normal. The x-ray revealed normal cardiothoracic ratio with mild haziness of the left lower segment of the lung (Fig. 1). Fibrooptic bronchoscopy showed normal vocal cord, trachea, and bronchopulmonary segments and their connections. Twodimensional echocardiography, pulsed-wave Doppler, CFDI, and contrast echo yielded normal findings. Barium swallow and meal and follow through were normal. A bronchogram indicated normal bronchopulmonary segments with mild caliber reduction in the segments of the bronchi of the left lower lobe. Other divisions of the bronchi and alveolar filling were normal. There was poor bronchial dye clearance from the left lower lobe bronchioles without cystoadenomatous malformation (Fig. 2). Aortic root and descending aortography showed a large anomalous systemic artery arising from the descending thoracic aorta (Fig. 3). It supplied the posterobasal segment of the left lower lobe, and the venous drainage was into the pulmonary vein and then into the left atrium (Fig. 4).
equal in all four limbs.
Discussion
Sequestration is a rare anomaly occurring in less than 7 % of all congenital lung malformations.’ It is more common in the left lower lobe.’ Sequestration can be divided into intralobar and extralobar forms. The extralobar form develops early in embryonic life, has its own pleural covering, is more common in males, and has no bronchial communication with the rest
Fic. 1. Chest x-ray, PA view, showing mild haziness of the lower segment of the left lung.
FIG. 2. Bronchogram of the left lung, PEA view, indicatmild caliber reduction of the left lower bronchioles without cystoadenomatous malformation.
ing
Downloaded from ang.sagepub.com at FLORIDA INTERNATIONAL UNIV on July 6, 2015
612
FIG. 3. Descending aortogram, PA view, showing opacification from a large anomalous artery arising from the descending thoracic aorta.
FIG. 4. Aortographm, LAO view, showing the anomalous systemic artery supplying the posterobasal segment of the left lower lobe. The venous drainage is into the pulmonary vein and then into the left atrium.
of the lung. Associated abnormalities like diaphragmatic hernia, pectus excavatum, congenital cardiac abnormalities, and bronchial communications with fore-gut are common. It has an anomalous systemic arterial supply from the descending thoracic aorta, and the venous drainage is into a systemic azygos or hemiazygos vein. It presents early in life with respiratory 2 distress and/or a triangular mass lesion on chest x-ray.2 The intralobar type can be divided into the cystic bronchiectatic and pseudotumorous forms. The cystic bronchiectatic group can be further divided into a solitary cystic, polycystic (most common), and mixed forms.’ The accessory lung bud develops earlier in embroyonic life than it does in the extralobar form, and so it gets incorporated within the normal lung and is invested by the normal pleura. This form shows no sex predilection, and associated malformations are rare. It has an anomalous systemic arterial supply from the descending thoracic aorta, and the venous draingage is into the pulmonary vein. It has a delayed clinical presentation ususally as a left lower lobe abscess cavity. Ours is a case of intralobar sequestration based on anomalous arterial supply, venous drainage into the pulmonary vein, normal bronchopulmonary segments, and their communications with the rest of the lung. In the past decade, contrast-enhanced tomography has been used to identify the anomalous vessel, which can be multiple in as many as 20% of cases.2 The wall of the anomalous systemic artery histopathologically resembles that of a pulmonary artery.’ Continuous murmurs sometimes occur in sequestration owing to significant flow through the systemic artery. Symptomatic intralobar sequestration requires lobectomy. The surgery should be performed during a quiescent phase and under antibiotic coverage. It is imperative to ligate the anomalous systemic vessel before lobectomy, failing which catastrophic hemorrhage may result. 2,4
Downloaded from ang.sagepub.com at FLORIDA INTERNATIONAL UNIV on July 6, 2015
613
Conclusion
diagnosis of sequestration is dependent on the identification of an anomalous systemic arterial supply to a segment of the lung, and its differentiation into extralobar and intralobar The
forms is based on the bronchial anatomy. Normal bronchial communications with the rest of the lung occur in intralobar forms, but communications are absent in extralobar forms. D.
Vaidiyanathan, M.D., D. M. Professor of Cardiology No. 7, Sylvan Lodge Colony Kilpauk Additional
Madras-10, India
References 1. Sir Crofton J, Douglas A: Congenital and Familial Conditions. Respiratory Diseases, ed. 3. Blackwell Scientific Publications, 1981, pp 136-138. 2. Ferguson TB: Congenital lesions of the lung and emphysema. In: Gibons Surgery of the Chest, vol 1, ed. 4. Philadelphia: W.B. Saunders Co, 1983, pp 684-688.
3. Savic B, Birtel FJ, Tholen W, et al: Lung sequestration : Report of seven cases and review of 540 published cases. Thorax 34:96-101, 1979. 4. Durnin RE, Lababidi Z, Butler C, et al: Bronchopulmonary sequestration. Chest 57:454-459, 1970.
Downloaded from ang.sagepub.com at FLORIDA INTERNATIONAL UNIV on July 6, 2015
as a
D. Vaidiyanathan, M.D., D.M. K. Meenakshi, M.D., D.M. S. Elangovan, M.D., D.M. J. Jeyachandran, M.D. V. Chockalingam, M.D., D.M.
and A.
Tajamul Hussain, M.D.,
D.M.
MADRAS, INDIA
Abstract An eighteen-year-old asymptomatic woman with a continuous murmur, normal two-dimensional echocardiogram, and mild haziness of the left lower segment of the lung on chest x-ray was diagnosed to have sequestration based on the presence of a large anomalous systemic artery arising from the descending thoracic aorta supplying the lower lobe of the left lung. Normal bronchial connections with the rest of the lung on bronchoscopy and delayed dye clearance from the left lower lobe bronchioles on bronchogram indicated its intralobar nature. The cause of the continuous murmur was thought to be the large flow through the anomalous systemic artery. Introduction
Pulmonary sequestration is the term applied to a congenital malformation characterized by of embryonic lung tissue that derives its blood supply from an anomalous systemic artery. The formation of an accessory lung bud caudal to the normal lung bud in embryonic life is the cause of this anomaly. The anomalous systemic artery is due to the persistence of the communications between the dorsal aorta and the splanchnic vascular bed. an area
CASE REPORT An
eighteen-year-old asymptomatic woman, bom of a nonconsanguineous parentage, was referred for the evaluation of a continuous murmur over the chest. There was no cyanosis, the mean jugular venous pressure was normal, and the blood pressure was 150/70 mmHg and From the
Department of Cardiology,
Government General
Hospital, Madras,
India
610 Downloaded from ang.sagepub.com at FLORIDA INTERNATIONAL UNIV on July 6, 2015
611
The heart sounds were normal and there was a continuous murmur that was best heard in the lower left interscapular and infrascapular regions. Other systems were normal. The patient was subjected to detailed clinical examination, electrocardiogram (ECG), twodimensional echocardiography, Doppler, color flow Doppler imaging (CFDI), chest x-ray, barium swallow, meal and follow through, fibrooptic bronchoscopy, bronchography, and aortography. The ECG appeared normal. The x-ray revealed normal cardiothoracic ratio with mild haziness of the left lower segment of the lung (Fig. 1). Fibrooptic bronchoscopy showed normal vocal cord, trachea, and bronchopulmonary segments and their connections. Twodimensional echocardiography, pulsed-wave Doppler, CFDI, and contrast echo yielded normal findings. Barium swallow and meal and follow through were normal. A bronchogram indicated normal bronchopulmonary segments with mild caliber reduction in the segments of the bronchi of the left lower lobe. Other divisions of the bronchi and alveolar filling were normal. There was poor bronchial dye clearance from the left lower lobe bronchioles without cystoadenomatous malformation (Fig. 2). Aortic root and descending aortography showed a large anomalous systemic artery arising from the descending thoracic aorta (Fig. 3). It supplied the posterobasal segment of the left lower lobe, and the venous drainage was into the pulmonary vein and then into the left atrium (Fig. 4).
equal in all four limbs.
Discussion
Sequestration is a rare anomaly occurring in less than 7 % of all congenital lung malformations.’ It is more common in the left lower lobe.’ Sequestration can be divided into intralobar and extralobar forms. The extralobar form develops early in embryonic life, has its own pleural covering, is more common in males, and has no bronchial communication with the rest
Fic. 1. Chest x-ray, PA view, showing mild haziness of the lower segment of the left lung.
FIG. 2. Bronchogram of the left lung, PEA view, indicatmild caliber reduction of the left lower bronchioles without cystoadenomatous malformation.
ing
Downloaded from ang.sagepub.com at FLORIDA INTERNATIONAL UNIV on July 6, 2015
612
FIG. 3. Descending aortogram, PA view, showing opacification from a large anomalous artery arising from the descending thoracic aorta.
FIG. 4. Aortographm, LAO view, showing the anomalous systemic artery supplying the posterobasal segment of the left lower lobe. The venous drainage is into the pulmonary vein and then into the left atrium.
of the lung. Associated abnormalities like diaphragmatic hernia, pectus excavatum, congenital cardiac abnormalities, and bronchial communications with fore-gut are common. It has an anomalous systemic arterial supply from the descending thoracic aorta, and the venous drainage is into a systemic azygos or hemiazygos vein. It presents early in life with respiratory 2 distress and/or a triangular mass lesion on chest x-ray.2 The intralobar type can be divided into the cystic bronchiectatic and pseudotumorous forms. The cystic bronchiectatic group can be further divided into a solitary cystic, polycystic (most common), and mixed forms.’ The accessory lung bud develops earlier in embroyonic life than it does in the extralobar form, and so it gets incorporated within the normal lung and is invested by the normal pleura. This form shows no sex predilection, and associated malformations are rare. It has an anomalous systemic arterial supply from the descending thoracic aorta, and the venous draingage is into the pulmonary vein. It has a delayed clinical presentation ususally as a left lower lobe abscess cavity. Ours is a case of intralobar sequestration based on anomalous arterial supply, venous drainage into the pulmonary vein, normal bronchopulmonary segments, and their communications with the rest of the lung. In the past decade, contrast-enhanced tomography has been used to identify the anomalous vessel, which can be multiple in as many as 20% of cases.2 The wall of the anomalous systemic artery histopathologically resembles that of a pulmonary artery.’ Continuous murmurs sometimes occur in sequestration owing to significant flow through the systemic artery. Symptomatic intralobar sequestration requires lobectomy. The surgery should be performed during a quiescent phase and under antibiotic coverage. It is imperative to ligate the anomalous systemic vessel before lobectomy, failing which catastrophic hemorrhage may result. 2,4
Downloaded from ang.sagepub.com at FLORIDA INTERNATIONAL UNIV on July 6, 2015
613
Conclusion
diagnosis of sequestration is dependent on the identification of an anomalous systemic arterial supply to a segment of the lung, and its differentiation into extralobar and intralobar The
forms is based on the bronchial anatomy. Normal bronchial communications with the rest of the lung occur in intralobar forms, but communications are absent in extralobar forms. D.
Vaidiyanathan, M.D., D. M. Professor of Cardiology No. 7, Sylvan Lodge Colony Kilpauk Additional
Madras-10, India
References 1. Sir Crofton J, Douglas A: Congenital and Familial Conditions. Respiratory Diseases, ed. 3. Blackwell Scientific Publications, 1981, pp 136-138. 2. Ferguson TB: Congenital lesions of the lung and emphysema. In: Gibons Surgery of the Chest, vol 1, ed. 4. Philadelphia: W.B. Saunders Co, 1983, pp 684-688.
3. Savic B, Birtel FJ, Tholen W, et al: Lung sequestration : Report of seven cases and review of 540 published cases. Thorax 34:96-101, 1979. 4. Durnin RE, Lababidi Z, Butler C, et al: Bronchopulmonary sequestration. Chest 57:454-459, 1970.
Downloaded from ang.sagepub.com at FLORIDA INTERNATIONAL UNIV on July 6, 2015
