Extra-anatomic bypass of the superior vena cava after successful stenting for fibrosing mediastinitis

Multimodality Imaging of Focal and Diffuse Fibrosing Mediastinitis

Fibrosing mediastinitis is a rare benign but potentially life-threatening process that occurs because of proliferation of fibrotic tissue in the mediastinum. The focal subtype is more common and typically is associated with an abnormal immunologic response to Histoplasma capsulatum infection. Affected patients are typically young at presentation, but a wide age range has been reported, without a predilection for either sex. The diffuse form may be idiopathic or associated with autoimmunity, usually affects middle-aged and/or elderly patients, and is more common in men. For both subtypes, patients present with signs and symptoms related to obstruction or compression of vital mediastinal structures. The most common presenting signs and symptoms are cough, dyspnea, recurrent pneumonia, hemoptysis, and pleuritic chest pain. Patients with the diffuse subtype may have additional extrathoracic symptoms depending on the other organ systems involved. Because symptom severity is variable, treatment should be individualized with therapies tailored to alleviate compression of the affected mediastinal structures. Characteristic imaging features of fibrosing mediastinitis include infiltrative mediastinal soft tissue (with or without calcification) with compression or obstruction of mediastinal vascular structures and/or the aerodigestive tract. When identified in the appropriate clinical setting, these characteristic features allow the radiologist to suggest the diagnosis of fibrosing mediastinitis. Careful assessment is crucial at initial and follow-up imaging for exclusion of underlying malignancy, assessment of disease progression, identification of complications, and evaluation of treatment response. Online supplemental material is available for this article. ^©RSNA, 2019.

[Treatment of chronic mediastinitis]

BACKGROUND

Chronic mediastinitis is a rare disorder characterized by the proliferation of fibrous tissue within the mediastinum resulting in compression of mediastinal structures.

OBJECTIVE

This article gives an overview of the treatment options for chronic mediastinitis.

MATERIAL AND METHODS

A literature search was carried out regarding treatment options for chronic mediastinitis

RESULTS AND CONCLUSION

Little is known about the pathogenesis of chronic mediastinitis, which has hampered the development of novel therapeutic approaches. There is no convincing evidence for the success of medicinal (antifungal or conventional anti-inflammatory) therapy and it is not recommended. In cases of clinical symptoms procedures for decompression, such as endovascular or endobronchial stents or surgical procedures, such as decompression interventions or extra-anatomic bypasses should be considered. The prognosis for unilateral involvement is better than for bilateral involvement if performed in specialized centers.

Operative strategies for pulmonary artery occlusion secondary to mediastinal fibrosis

BACKGROUND

Fibrosing mediastinitis is a rare disease characterized by an excessive fibrotic reaction in the mediastinum, which may entrap mediastinal structures including the pulmonary arteries. Our objectives were to assess the surgical strategies and outcomes of repair of pulmonary artery occlusion attributable to mediastinal fibrosis.

METHODS

With approval from the Mayo Clinic Institutional Review Board, we identified all patients with fibrosing mediastinitis who underwent an operation for relief of pulmonary artery obstruction between 1980 and 2008. Perioperative data were collected using medical records and late follow-up surveys.

RESULTS

Operative procedures to bypass or reconstruct an obstructed pulmonary artery were performed in 5 patients. Patients' median age was 40 years (range, 27 to 51 years), and all patients were symptomatic and had right ventricular hypertension. In 3 patients, a double-outlet right ventricle was constructed using a valved conduit (porcine valved conduit, n = 1; aortic homograft, n = 2) from the right ventricle to the right pulmonary artery. Two patients required complete reconstruction of the pulmonary artery confluence using a pulmonary homograft in 1 patient and a hybrid technique of autologous pericardial reconstruction and intraoperative stenting in another patient. All patients had a reduction in right ventricular pressures after operation. One patient died perioperatively owing to respiratory failure; the remaining 4 patients were alive at a median follow-up of 7.4 years (range, 0.5 to 14.7 years). One patient required late balloon dilatation of the conduit and distal pulmonary arteries 10 years after initial operation, but the remaining conduits were widely patent at late follow-up. Late functional improvement was limited owing to other complications from mediastinal fibrosis or other comorbidities.

CONCLUSIONS

Treatment of pulmonary artery occlusion attributable to mediastinal fibrosis can be challenging. Successful operative strategies include both creation of a double-outlet right ventricle and complete reconstruction of the pulmonary artery confluence. Hybrid techniques of both conduit placement and stenting should also be considered for patients with occluded pulmonary arteries.