Case Analysis

The cause of death in this patient was an acute antero-septal myocardial infarction, which was evident by the chest pain, elevated enzymes (LDH, CK and SGPT) and ECG changes. However, the most significant findings were related to the aorta and coronary arteries. The gross and microscopic changes in combination with the clinical history and distribution of lesions (e.g. large caliber vessels and branches), are in keeping with the diagnosis of aortitis and coronary arteritis. Although many of the findings described, such as intimal fibrosis, cholesterol clefts and focal calcification, are by themselves indicative of atherosclerosis and non-specific, their occurrence in a young woman, especially in association with focal inflammation of the vessel wall, support this diagnosis. Furthermore, atherosclerosis may be superimposed upon a vessel damaged by vasculitis.

The forms of vasculitis that affect large vessels include: Giant cell arteritis and Takayasu's arteritis. Giant cell arteritis occurs in patients over 50 years and commonly involves small muscular arteries such as the temporal and carotid arteries. Two histologic variants have been described: 1) granulomatous with giant cells and mononuclear cells infiltrating the inner half of the media; and, 2) non-specific panarteritis that comprises a mixed inflammatory infiltrate. Although giant cell arteritis has a female preponderance and carotid involvement, our patient was young and did not have evidence of temporal arteritis.

Takayasu's arteritis (TA) is a disease of younger individuals, particularly females and it is the most likely diagnosis in this case. It is characterized by a panarteritis that may affect any segment of the aorta and its branches. It is presumably an autoimmune disorder that in early phases presents with non-specific symptoms but later evolves into a more severe disease. The symptoms are related to the portion of aorta that becomes involved. In this patient, symptoms such as chest pain, dyspnea and shortness of breath associated with hypoxemia, were due to acute pulmonary edema secondary to myocardial infarction caused by the inflammation and subsequent thrombotic occlusion of the coronary vessels. This last event was preceded by episodes of angina pectoris and angina intestinalis (the postpyramidal abdominal pain was related to mesenteric involvement). She was hypotensive due to decreased peripheral vascular resistance. However, it is significant that there was no history of hypertension, which is a common symptom in TA as it is related to renal artery stenosis. The patient had no involvement of the right renal artery, and in the left side, one of the two vessels was patent and maintained the function of the upper 1/3 of the left kidney; therefore, sparing her of renovascular hypertension. The left pulmonary artery showed intimal proliferation and thickened adventitial vessels with perivascular infiltrates. These changes were focal with no significant occlusion; thus, the absence of pulmonary hypertension and right ventricular hypertrophy. It is worth mentioning that TA may present with a distinct pulmonary arteriopathy that consists of outer media defects with capillary ingrowth in this layer and in the thickened and fibrosed intima.

The occlusion of the subclavian and iliac arteries was responsible for the diminished or absent peripheral pulses. The asymmetry as well as the absence of the peripheral pulses is quite characteristic of this entity, hence the term "pulseless" disease. TA is not a common disorder; therefore, other causes of reduced peripheral pulses should be considered such as arteriosclerotic occlusive disease, coarctation of the aorta, syphilis and neoplasias.

Coarctation of the aorta is more common in males and in patients with gonadal dysgenesis. It is also associated with other congenital cardiac abnormalities in approximately 10% of cases. It presents in early childhood unless the coarctation is distal to the ductus arteriosus, in which case the onset of symptoms occurs much later in life. This could have been a consideration in this case, because coarctation of the aorta can present with diminished pulses in the lower extremities. Additionally, it is associated with cardiomegaly, hypertension in the arms and engorged collateral vessels in the intercostal and subscapular areas. Both the clinical history and autopsy did not reveal any of these findings in our patient. Coarctation of the aorta has a characteristic chest X ray with a "3" sign made by the stenotic area and the 2 adjacent dilated segments. The ECG and echocardiogram invariably show left ventricular hypertrophy, but other findings depend on the location of the coarctation and presence of other heart anomalies.

Syphilis is another form of arteritis that might be considered in this case, but it is usually seen in older patients and most often spares the abdominal aorta. The characteristics features of syphilitic arteritis were not present in our patient. Although there was perivascular inflammation involving the vasa vasorum of the adventitia, it was not prominent and the infiltrate did not consist predominantly of plasma cells.

TA is suspected to be an autoimmune disorder, but the etiology and pathogenesis are not known. HLA typing studies have shown some correlation with the markers HLA-A10, B5 Bw52, DR2, DR4, and MB1. In addition, TA has been associated with other diseases. One of these, is ulcerative colitis, a gastro-intestinal inflammatory disease in which HLA DR2 expression has also been described. Another important association is the one between TA and ankylosing spondylitis, despite the lack of association between TA and the expression of HLA-B27, which is frequently present in ankylosing spondylitis. Some authors have proposed that TA may be the result of an abnormal immune response elicited by certain infectious organisms (e.g. acid fast bacilli). As in other forms of vasculitis, sensitized T cells have been considered to play an important role in the manifestation of the disease. Abnormal endocrine manifestations have also been reported, which may be an interesting observation, since our patient had a history of hyperthyroidism of unclear etiology.

Suggested Readings

1. Kerr G. Takayasu's arteritis. Curr Opin Rheumatol. 1994; 6: 32-8.

2. Matsubara O; Kuwata T; Nemoto T; Kasuga T; Numano F. Coronary artery lesions in Takayasu arteritis: pathological considerations. Heart Vessels Suppl. 1992; 7:26-31.

3. Hall S; Buchbinder R. Takayasu's arteritis. Rheum Dis Clin North Am. 1990; 16:411-22.

4. Rizzi R, Bruno S, Stellacci C, Dammacco R. Takayasu's arteritis: a cellmediated large-vessel vasculitis. Int J Clin Lab Res. 1999; 29:8-13.

5. Morita Y, Yamamura M, Suwaki K, Mima A, Ishizu T, Hirohata M, Kashihara N, Makino H, Ota Z. Takayasu's arteritis associated with ulcerative colitis; genetic factors in this association. Intern Med. 1996; 35:574-8.

Bifurcated Left Renal Vein

Figure S3. Takayasu's arteritis. Segment of aorta narrowed before the bifurcation into the common iliac arteries (RRA = right renal artery, LRA = left renal artery,

Takayasu Arteritis Histology
Figure 84. Takayasu's arteritis, histologic section. Granulomatous inflammation involving the adventitia of the aorta. The infiltrate consists of lymphocytes, hystiocytes
Reducing Blood Pressure Naturally

Reducing Blood Pressure Naturally

Do You Suffer From High Blood Pressure? Do You Feel Like This Silent Killer Might Be Stalking You? Have you been diagnosed or pre-hypertension and hypertension? Then JOIN THE CROWD Nearly 1 in 3 adults in the United States suffer from High Blood Pressure and only 1 in 3 adults are actually aware that they have it.

Get My Free Ebook

Post a comment