INTRODUCTION: Tracheal obstruction can have many underlying causes. Commonly encountered causes are neoplastic and benign stenoses. In adults, rare cases of tracheal obstruction are caused from external compression from vascular structures. This case demonstrates airway compromise caused by a combination of an innominate artery aneurysm and severe kyphoscoliosis.
CASE PRESENTATION: An 86 year old woman was admitted to the hospital for “shortness of breath.” Her medical history was remarkable for severe kyphoscoliosis and hypertension, and she was gainfully employed in a full time job as a cashier. She had been hospitalized several times over the last year with symptoms of feeling as though she were choking, chest tightness, wheezing, and intermittent stridor. Her symptoms were relieved with stretching/straightening her neck and leaning her head back, as well as with the use of nebulizers and humidified air. The patient reported that she never had any problems with her breathing until the last year, and she was a life long non-smoker. She was transferred to our hospital after a CT scan of the neck and chest was performed which revealed her trachea to be significantly compromised anteriorly by an innominate artery aneurysm and posteriorly by the anterior portion of her cervical spine. Reconstructed tracheal images revealed a tracheal diameter of 11.5mm at the narrowest point; on bronschoscopic exam, the diameter at maximum was 11.5mm however there was intermittent near complete obstruction of the trachea with pulsation of the innominate artery. A multidisciplinary team including interventional pulmonology, thoracic surgery, vascular surgery, and otolaryngology was involved in the case. The team concluded that endovascular stenting of the innominate artery aneurysm would not have alleviated the pressure in the innominate artery and therefore not alleviate the tracheal compression. Tracheostomy was felt risky; secondary to her severe cervical kyphoscoliosis the tip of the trach tube would lay at the level of the arterial aneurysm with increased theoretical risk of tracheo-arterial fistula. Cardiothoracic surgery reccommended open aneurysmal repair. The patient opted first for non-surgical attempts to alleviate her symptoms. Airway management included a series of rigid bronchoscopies. The first procedure entailed balloon dilation of the stenosed area to 15mm, followed by placement of a Dumon (Bryan Corp, Woburn MA) 16mm x 50mm stent - placed 3cm above the carina. Difficulties with cough ensued, with migration of the stent. The stent was repositioned back to its original location during the second rigid bronchoscopy. Further problems with cough, stent migration, and mucous clearance ensued. To achieve less stent migration, the decision was made to change from a Dumon stent to an Ultraflex (Boston Scientific, Natick MA) 20mm x 40mm covered metallic stent. The patient improved symptomatically and was able to return home with minimal respiratory limitation.
DISCUSSIONS: Innominate artery aneurysms causing tracheal stenosis have been reported in the medical literature. The epidemiology of these aneurysms ranges from Marfan's Syndrome, vasculitidies including Takayusu's arteritis, infectious causes such as leutic aneurysms, iatrogenically from line placements, and from hypertension. Treatment options include treating underlying diseases such as controlling hypertension, surgical resection, and now a successful case of endotracheal stenting relieving obstruction.
CONCLUSION: Innominate artery aneurysms in adulthood are rare. Management when causing tracheal compromise should take a multidisciplinary approach as medical, surgical and interventional pulmonology options are available. From our literature search this is the first tracheal obstruction case secondary to innominate artery aneurysm treated successfully with endotracheal stenting.
DISCLOSURE: Catherine Grossman, None.