Ann Thorac Surg 2005;80:2368-2370
© 2005 The Society of Thoracic Surgeons
Case report
Mediastinal Fibrosis Causing Myocardial Ischemia
Pankaj Saxena, MCh
*
,
Peter J. Tesar, FRACS
Department of Cardiac Surgery, The Prince Charles Hospital, Brisbane, Australia
Accepted for publication July 14, 2004.
* Address correspondence to Dr Saxena, Department of Cardiac Surgery, The Prince Charles Hospital, Rode Rd, Chermside, Brisbane 4032, Australia (Email: drpankajsaxena{at}hotmail.com).
 |
Abstract
|
|---|
This report describes an unusual etiology of coronary artery disease. A 60-year-old male presented with angina. He was treated with methysergide for migraine. It was determined that the patient possessed an extremely thick-walled ascending aorta that caused the coronary ostial narrowing. He underwent replacement of the ascending aorta and proximal aortic arch. Double vessel coronary artery bypass grafting was performed using saphenous vein. Microscopic examination indicated the pathology to be sclerosing mediastinis.
|
Introduction
|
|---|
Mediastinal fibrosis is an uncommon condition of diverse etiology. This condition can render different manifestations depending upon the structures involved. Narrowing of the coronary arteries by drug-induced sclerosing mediastinitis is a very uncommon entity.
A 60-year-old white male presented with a history of angina pectoris spanning a 15-month duration. A 30-year background history included hypertension, dyslipidemia, and migraine. For nearly 20 years the migraines were treated with methysergide. Clinical examination was normal. Computerized tomography and magnetic resonance imaging demonstrated the presence of a cuff of tissue indicating intermediate density that surrounded the ascending aorta distal to the aortic valve and extended to the proximal aortic arch with involvement of the innominate artery (Fig 1). There was no aneurysm or aortic dissection. The aortic wall was thickened and approached 1 cm in the involved portion. Transesophageal echocardiography identified normal cardiac valves and normal left ventricular function. The patient was human leukocyte antigen B (HLAB27) negative and also indicated a negative serology for syphilis and connective tissue disorders. Coronary angiography indicated the presence of 50% ostial narrowing of both the left main and right coronary arteries (Fig 2). Based on radiologic appearances a probable diagnosis of intramural hematoma or aortitis was considered. Surgical treatment was considered because of considerably apparent coronary artery disease as well as to establish aortic pathology.
View larger version (145K):
[in this window]
[in a new window]
|
Fig 2. Coronary angiography indicating the involvement of left coronary artery ostium by aortic fibrosis (arrow).
|
|
A median sternotomy was performed. There were dense intrapericardial adhesions surrounding the ascending aorta and there was evidence of severe inflammation and thickening of the ascending aortic wall. Cardiopulmonary bypass was established with femoral arterial cannulation and a two-stage single venous cannula in the right atrium. Ascending aortic and proximal aortic arch were dissected on bypass. The heart, other great vessels, and epicardial coronary arteries were of normal appearance. Systemic cooling was actualized to 18°C. Distal coronary anastomoses were fashioned on fibrillating heart using reversed segments of great saphenous vein grafts to left anterior descending and right coronary arteries. The target vessels were 2 mm in size and were free from disease. Total circulatory arrest was achieved. During aortotomy it was noted that the aortic wall was very thick and fibrous (Fig 3). The aortic valve was indicated to be normal. There was narrowing of the coronary ostia caused by aortic wall disease. The wall of the innominate artery was normal and was originating from the abnormal segment of the aorta. The wall of the aorta beyond the origin of the left common carotid artery was relatively thin. Retrograde cerebral perfusion was used. Replacement of the ascending aorta and proximal arch was created using a 20-mm double velour Dacron graft. Innominate and left common carotid arteries were reimplanted on aortic graft using a 12-mm sized Dacron graft. The total circulatory arrest time was 45 minutes. Proximal anastomoses of the vein grafts were performed on the aortic graft during rewarming. Frozen sections of the aortic tissue did not reveal any particular pathology except for the presence of inflammatory cells and fibrosis. The patient experienced an uneventful recovery. Microscopic examination of the specimen was consistent with a minimal intimal atheroma and a normal appearance of the aortic media. There was a marked degree of collagenous thickening regarding the aortic adventitia with paucicellular inflammatory cell infiltration with lymphocytes (Fig 4). There was no evidence of tubercular or fungal granulomas, syphilis, cystic medial necrosis, or malignancy. These appearances were consistent with a diagnosis of sclerosing mediastinitis involving the aorta. The patient was discharged on postoperative day 6. Fungal and tubercular cultures did not indicate any organism growth.
View larger version (162K):
[in this window]
[in a new window]
|
Fig 4. Microphotographs illustrating the process of adventitial sclerosis and inflammatory infiltrate (hematoxylin & eosin, x100).
|
|
|
Comment
|
|---|
Sclerosing or fibrosing mediastinitis is an uncommon chronic inflammatory disorder of diverse etiology. Histoplasma, mycobacteria, nocardia, Hodgkin's disease, sarcoidosis, some collagen vascular autoimmune disorders, and the use of methysergide for the treatment of migraines can cause this process. There is also an association with other fibroinflammatory disorders like retroperitoneal fibrosis, sclerosing cholangitis, orbital pseudotumor, and Riedel thyroiditis [1, 2]. The entity causes the encasement of mediastinal structures. Delayed hypersensitivity reactions to fungal, mycobacterial, or other unknown antigens can cause this reaction. Methysergide is known to promote fibrosis in cardiovascular and pulmonary structures [3]. Histopathology indicates dense bundles and sheets of hyalinized collagen admixed with a relatively sparse inflammatory infiltrate.
The process can involve any mediastinal structure. The superior vena cava is the most often involved structure because it possesses thin walls and a low intraluminal pressure. The tracheobronchial tree, pulmonary artery and vein, esophagus, atrium, inferior vena cava, thoracic duct, and left recurrent laryngeal nerve have been reported to in the literature [4] to also be associated. Involvement of the coronary arteries is extremely rare. Reed described a patient who presented with congestive cardiac failure and bilateral ureteric obstruction. On autopsy he was determined to exhibit retroperitoneal fibrosis and massive periaortic fibrosis in the infrarenal abdominal aorta. The coronary arteries were markedly sclerotic with some distal involvement. In retrospect this patient probably exhibited sclerosing mediastinitis with a pattern of coronary artery and aortic involvement different from the present patient. Another interesting report described a thick fibrotic ring involving the aortic root and the left coronary orifice. Aleksic and associates described a patient who underwent coronary artery bypass surgery regarding the association of the left anterior descending and left circumflex coronary arteries from mediastinal fibrosis involving the ascending aorta. Coronary ostial narrowing of 50% precluded arterial revascularization with regard to the risk of late-phase graft occlusion in our patient [5–7].
This article describes the management of the otherwise uncommon involvement of the thoracic aorta and the extremely rare involvement of the coronary ostia caused by sclerosing mediastinitis. In the absence of other causal factors, we believe that with regard to our patient, methysergide is responsible for the development of mediastinal fibrosis.
|
References
|
|---|
- Dehner LP, Coffin CM. Idiopathic fibrosclerotic disorders and other inflammatory pseudotumors Sem Diag Pathol 1998;15:161-173.
- Flannery MT, Espino M, Altus P, et al. Hodgkin's disease masquerading as sclerosing mediastinitis South Med J 1994;87:921-923.[Medline]
- Popham BI, Stevenson TD. Idiopathic retroperitoneal fibrosis associated with coagulation defect (factor deficiency) Ann Intern Med 1960;52:894-906.
- Schwengerdt CG, Suyemoto R, Main FB. Granulomatous and fibrous mediastinitisa review and analysis of 180 cases. J Thorac Cardiovascular Surg 1969;57:365-379.[Medline]
- Reed GW, Stinely RW. Massive periaortic and periarterial fibrosisreport of a case. New Engl J Med 1959;261:320-333.
- Graham JR, Suby HI, LeCompte PR, et al. New Engl J Med 1966;274:359-368.
- Aleksic I, Saldaña F, Busch T, et al. Ann Thorac Surg 1999;67:224-225.[Abstract/Free Full Text]
This article has been cited by other articles:
|
|
|
|
 
P. Saxena and P. J. Tesar
Vascular obstruction related to mediastinal fibrosis: an interesting clinical entity.
J. Thorac. Cardiovasc. Surg.,
November 1, 2007;
134(5):
1379 - 1379.
[Full Text]
[PDF]
|
|
|
|
|
|
|
C. Zhang, Y. Ni, and J. Zhang
Reply to the Editor.
J. Thorac. Cardiovasc. Surg.,
November 1, 2007;
134(5):
1379 - 1380.
[Full Text]
[PDF]
|
|
|
Top
Abstract
Introduction
