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Idhrees et al. Vessel Plus 2020;4:23 I http://dx.doi.org/10.20517/2574-1209.2020.15 Page 7 of 10
[48]
HLA classes I and II, and ICAM-1, indicating the involvement of an active inflammatory process . A
study of 204 Korean patients showed elevated NT-proBNP in active TA. The possible reasons for the rise
could have been due to elevated filling pressure of the ventricles, pulmonary arterial hypertension, left
[49]
ventricular failure and/or AR in these patients .
PULMONARY ARTERITIS
Pulmonary arteritis (PA) involvement in TA is not uncommon. The incidence of PA in patients with TA
varies greatly in the literature (0-56%) [50,51] . Pulmonary hypertension occurs in 12% to 13% of patients
with TA and in 42.2% of patients with PA [51,52] . As the patients present with non-specific respiratory
symptoms and lack of vessel involvement, the diagnosis is usually delayed in these patients. PA manifests
[52]
as pulmonary hypertension, which indicates a weak response to treatment and carries a poor prognosis .
[53]
The median time from the initial symptoms to definitive diagnosis is 13.5 (1-186) months . High-dose
glucocorticoid remains the standard of care and a combination of glucocorticoid and methotrexate or
azathioprine prolongs disease remission. Few case reports of successful pulmonary artery revascularisations
exist in the literature, but they are reserved for renal vascular hypertension, extremity claudication or
[52]
cerebral vascular disease .

AORTIC VALVE AND AORTIC ROOT
A study of 1,069 patients from China showed that more than one-third (34.9%) of the TA patients had
cardiac valve involvement . Regurgitation lesions are more common than stenosis, with AR being the
[24]
[54]
commonest lesion in TA patients. AR in TA was first described by Jervell in 1954 . The incidence of AR
ranges from 20.0% to 44.8% in different populations [17,55,56] .
Pathogenesis
It is believed that inflammation rarely involves the aortic valve and that AR develops primarily as a result of
annular dilatation. The T lymphocytes and macrophages after infiltration, initiate an immunologic cascade
in the aortic wall. This causes release of cytokines and matrix metalloproteinases, destroying the aortic
wall [57-59] . The inflammation involves the aortic wall from the adventitia to intima, damaging the media.
[24]
This will make the aortic root fragile, which in turn is unable to bear the stress and start to dilate . The
secondary AR jet induces morphological changes in the aortic valve leaflets such as fibrous thickening and
enrolling and thereby worsens the AR itself.

Management
[24]
Chronic AR leads to heart failure, which is the main cause of death in patients with TA . Hence, the
presence of AR necessitates early surgery before decompensating. However, surgical treatment of AR in
TA is difficult because of the need to manipulate fragile and inflamed tissue. The disease actively has to be
monitored as mentioned earlier. When examining a patient with AR, the physician should be aware of the
common differential diagnosis in valvular heart disease- rheumatic heart disease, degenerative valvular
heart. Echocardiogram should identify the pathology of the valve and establish the diagnosis.

Patients who undergo surgery are prone to prosthetic valve detachment, paravalvular leak or
pseudoaneurysm at the anastomotic site. The incidence of postoperative anastomotic aneurysm has been
reported to be 8.5%-13.8%, while that of the prosthetic valve detachment has been reported as 4%-25% in
different series . Miyata et al. reported that occurrence of anastomotic aneurysm was not related to the
[60]
[61]
presence of inflammation, preoperative use of steroids, or pathological stage. This anastomotic aneurysm
could develop any time after the operation, and hence, the patients require alifelong surveillance. There are
[62]
concerns about the dilatation of the ascending aorta after aortic valve replacement alone. Bougioukas et al.
proposed avoiding valve-sparing aortic root replacement in TA patients, as there is a high incidence of