Ortner’s syndrome is a rare cause of left recurrent laryngeal nerve palsy. The enlargement of any intrathoracic structure close to the recurrent laryngeal nerve such as left atrial enlargement, dilatation of the left pulmonary artery, or thoracic aortic aneurysm can result in a compressive nerve palsy2, 3. In the superior mediastinum, the left recurrent laryngeal nerve is a branch of the vagus nerve that descends down antero-lateral to the arch of aorta, passes deep to the ligamentum arteriosum and then ascends in the tracheo-oesophageal groove. The nerve can be compressed by a widening aortic aneurysm sac at the aorta4. 3 of our patients had hoarseness as the first symptom, their aneurysms were mainly arising from the arch and proximal descending aorta. In another patient, the position where the diameter of aneurysm increased due to endoleak was similar. These may be related to the anatomical position of the recurrent laryngeal nerve.
Generally, patients with hoarseness leads them to the otolaryngologist for evaluation. Although, the laryngoscopy can diagnose vocal cord paralysis easily, the differential diagnosis can be challenging5. Most vocal cord paralysis is due to neoplasia, followed by iatrogenic procedures, and the intracranial diseases or aortic diseases need to be considered too. In aortic disease, in addition to TAA, mycotic aneurysm and aortic dissection may also cause hoarseness, and most of the latter two have other symptoms2, 4, 6. Most TAAs are asymptomatic, but part of TAA patients may have other symptoms include dysphagia due to compression of the oesophagus and breathing difficulties due to incomplete opening of the glottis7. Therefore, when the common cause of hoarseness is not found, beware of hoarseness caused by compression of the left recurrent laryngeal nerve, and the chest CT or X-ray may be ordered.
The management of aortic aneurysm disease mainly includes stent-graft repair of thoracic aneurysms and open surgery with aorta replacement8. According to the patient's condition, our patients opting for TEVAR, combining with chimney graft and hybrid repair of thoracic aortic aneurysms. Early diagnosis of Ortner syndrome may be helpful in starting immediate treatment to restore vocal cord function and prevent permanent damage to the left recurrent laryngeal nerve. Voice improvement is expected within a few weeks of surgery and hoarseness has been reported to resolve completely at least within 4 months after surgery7. Endovascular stent grafting of the underlying TAA causes progressive shrinkage of the excluded and thrombosed aneurysm reducing the nerve compression leading to resolution of the left recurrent laryngeal nerve palsy.
In our patients, 1 patient’s symptom was fully recovered, 2 patients had partially improvement of hoarseness, and 1 patient’s hoarseness remained. Among them, patients who were treated earlier recovered better (Table 1). The patient with no improvement received treatment 2 years later after his hoarseness onset. These results indicate that for patients with Ortner syndrome secondary to thoracic aortic aneurysm, early treatment may be beneficial to restore vocal cord function.