A Rare Anatomical Variant of Pulmonary Sequestration

Abstract

SESSION TITLE: Fellow Case Report Slide: Pulmonary Critical Care Disorders: Think Twice SESSION TYPE: Affiliate Case Report Slide PRESENTED ON: Sunday, October 23, 2016 at 10:45 AM - 12:00 PM INTRODUCTION: Pulmonary sequestrations are a rare congenital anomaly of the lung, rarely diagnosed in adults and rarely found in the right middle lobe (RML). CASE PRESENTATION: A 68 year old woman with granulomatous lung disease, right middle lobe and right lower lobe bronchiectasis, and prior history of massive hemoptysis treated with bronchial artery embolization presented with multiple episodes of bronchitis and pneumonia before developing recurrent episodes of gross hemoptysis. Bronchoscopy demonstrated recent but no active bleeding which seemed to localize to the RML. There were no malignant cells on bronchial wash. With continued hemoptysis over a month later, a video-assisted thorascopic surgery for a right middle lobe lobectomy was planned. Review of computerized tomography images performed with intravenous contrast suggested a feeding artery originating from the right renal artery, therefore to mitigate intraoperative bleeding, a coil embolization of the feeding artery was performed. Pathology was consistent with intralobar pulmonary sequestration. Intraoperative wound cultures grew Pseudomonas aeruginosa species identical to previous sputum cultures. DISCUSSION: Pulmonary sequestrations occur most commonly in the left lower lobe (71.5%) and right lower lobe (26.0%) with systemic blood supplies most commonly originating from the thoracic (76.6%) and abdominal aorta (18.5%). In one case series of 2,625 patients with pulmonary sequestration, only two cases involved the RML (0.08%). A few other RML sequestrations have been reported separately — one receiving its systemic blood supply from an aberrant artery in the fissure, one from left coronary artery, and another with multiple feeding arteries from the internal mammary artery and the diaphragmatic artery. To our knowledge, there was only one other case receiving its systemic blood supply from the renal artery. These cases highlight the diversity of anatomical possibilities of pulmonary sequestrations. CONCLUSIONS: Right middle lobe sequestrations are exceedingly rare and may receive systemic blood supply from sources as distal as the renal arteries. This highlights the importance of preoperative angiography and consideration of embolization. Reference #1: Hamaji M. Int J Surg Case Rep. 2013; 4(10):861-862. Reference #2: Wei Y and Li Fan. Eur J Cardiothoracic Surgery. 2011; 40: e39-42. Reference #3: Xie D. Ann Thorac Surg. 2013;96:e131. DISCLOSURE: The following authors have nothing to disclose: Jennifer Fu, Aaron Parrish, Yvonne Carter, Janine Vintch No Product/Research Disclosure Information