18 F-Fluorodeoxyglucose-Positron Emission Tomography As an Imaging Biomarker in a Prospective, Longitudinal Cohort of Patients With Large Vessel Vasculitis

Vascular calcification in patients with large-vessel vasculitis compared to patients with hyperlipidemia

OBJECTIVE

Calcification of the coronary arteries, aorta, and branch vessels can occur in both large-vessel vasculitis (LVV) and atherosclerosis. The study objective was to determine the location and amount of vascular calcification in patients with LVV versus hyperlipidemia (HLD) and to identify risk factors associated with vascular calcification in LVV.

METHODS

Patients with giant cell arteritis (GCA), Takayasu's arteritis (TAK), and HLD underwent non-contrast computed tomography of the aorta and branch vessels. Vascular calcification in 14 specific arterial territories (4 segments of the aorta, 9 branch arteries, and the coronary arteries) was quantified throughout the large arteries by a cumulative Agatston score. Multivariate linear regression analyses were used to identify associations between traditional and disease-specific risk factors and total Agatston score.

RESULTS

A total of 88 subjects, including GCA (n = 29); TAK (n = 22); and HLD (n = 37), participated. Prevalence of vascular calcification in the aorta and branch vessels significantly differed in the coronary arteries (HLD = 67%, GCA = 35%, TAK = 9%, p < 0.01). Total Agatston scores were higher in GCA (median 3260, range 25-18,138) versus HLD (460, 19-17,215) (p < 0.01) but did not significantly differ between GCA and TAK (1944, 52-47,520) (p = 0.53). In multivariable regression analysis, age, type of vasculitis, and prednisone use was associated with vascular calcification in LVV.

CONCLUSION

The prevalence of coronary artery calcification is lower in LVV compared to HLD, but the amount of total vascular calcification throughout the large arteries is greater in LVV. Both traditional and disease-specific risk factors are associated with vascular calcification in LVV.

Clinical presentation, treatment and outcome of Takayasu's arteritis in southern Chinese: a multicenter retrospective study

To study the clinical presentation, treatment and outcome of southern Chinese patients with Takayasu's arteritis (TA). This is a retrospective chart review study of 78 patients managed in 14 public hospitals in Hong Kong between the years 2000 and 2010. Patients were identified from the hospital registry using the ICD-10 diagnostic code of the disease. The classification of TA was based on the American College of Rheumatology (ACR) or modified Ichikawa's criteria. Demographic data, clinical presentation, angiographic findings, pattern of vascular involvement (Numano's classification), treatment and outcome of these patients were presented. 78 patients were studied (82% women, age at presentation 34.2 ± 14 years). The estimated point prevalence of TA was 11/million population. The commonest initial manifestations were hypertension (62%) and vascular ischemic symptoms (38%). Systemic symptoms occurred in nine (12%) patients only. The proportion of patients fulfilling the angiographic subtypes of the Numano's classification was: types I (13%), IIa (4%), IIb (12%), III (12%), IV (20%) and V (39%), respectively. Thirty-two patients (41%) were treated with high-dose glucocorticoids (GCs) and 22 patients (28%) received additional non-GC immunosuppressive drugs. Vascular complications occurred in 26 (33%) patients and revascularization surgery was performed in 23(29%) patients. Three (4%) patients died of vascular complication at a median of 8 years after disease onset. TA is rare in southern Chinese patients of Hong Kong. Most patients present with ischemic symptoms during the stenotic phase of the disease. Although mortality is low, a significant proportion of patients developed vascular stenosis that required surgical interventions. More awareness of TA as a differential diagnosis of non-specific systemic symptoms with elevated inflammatory markers in younger patients is needed for earlier diagnosis.

Surgical intervention and its role in Takayasu arteritis

Vascular surgery remains an important option in the management of Takayasu arteritis (TA). Its use is predominantly confined to the treatment of symptomatic organ ischaemia or life-threatening aneurysm formation. In most cases, this follows the failure of medical therapy to prevent arterial injury. Open surgery and endovascular approaches are used. The choice between them, at least in part, is determined by the site and nature of the lesion. Open surgery, although more invasive, offers enhanced duration of arterial patency, whereas for endovascular intervention, primary angioplasty without stenting is preferred, with stenting reserved for primary or secondary angioplasty failures. Although there is increasing interest in the role of stent grafts and tailor-made endovascular stents, long-term outcomes remain to be reported. Interventional outcomes are improved and complications reduced by therapeutic control of disease activity before and after surgery. The wider use of combined immunosuppression and the introduction of biologic therapy for refractory TA may reduce future requirements for surgical intervention.

Use of Noninvasive Imaging in Giant Cell Arteritis

Giant cell arteritis (GCA) requires a prompt diagnosis to avoid significant morbidity among the elderly. An accurate diagnosis is also paramount given the side effect profile of long-term corticosteroid treatment. Temporal artery biopsy (TAB) has long remained the gold standard for the diagnosis of GCA but requires an invasive procedure that is not without risk. This article discusses the argument for and against the use of noninvasive imaging including ultrasound, magnetic resonance imaging, and positron emission tomography scanning for the diagnosis of GCA. It also provides a suggested diagnostic algorithm for when to consider noninvasive imaging versus TAB.

Arterial lesions in giant cell arteritis: A longitudinal study

OBJECTIVES

To evaluate large-vessel (LV) abnormalities on serial imaging in patients with giant cell arteritis (GCA) and discern predictors of new lesions.

METHODS

Clinical and imaging data from patients with GCA (including subjects diagnosed by LV imaging) enrolled in a prospective, multicenter, longitudinal study and/or a randomized clinical trial were included. New arterial lesions were defined as a lesion in a previously unaffected artery.

RESULTS

The study included 187 patients with GCA, 146 (78%) female, mean (±SD) age at diagnosis 68.5 ± 8.5 years; 39% diagnosed by LV imaging. At least one arterial lesion was present in 123 (66%) on the first study. The most frequently affected arteries were subclavian (42%), axillary (32%), and thoracic aorta (20%). In 106 patients (57%) with serial imaging, new arterial lesions were noted in 41 patients (39%), all of whom had a baseline abnormality, over a mean (±SD) follow-up of 4.39 (2.22) years. New abnormalities were observed in 33% patients by year 2; clinical features of active disease were present at only 50% of these cases. There were no differences in age, sex, temporal artery biopsy positivity, or disease activity in patients with or without new lesions.

CONCLUSIONS

In this cohort of patients with GCA, LV abnormalities on first imaging were common. Development of new arterial lesions occurred in patients with arterial abnormalities at first imaging, often in the absence of symptoms of active disease. Arterial imaging should be considered in all patients with GCA at diagnosis and serial imaging at least in patients with baseline abnormalities.

Comparison of magnetic resonance angiography and 18F-fluorodeoxyglucose positron emission tomography in large-vessel vasculitis

OBJECTIVES

To assess agreement between interpretation of magnetic resonance angiography (MRA) and ¹⁸F-fluorodeoxyglucose positron emission tomography (PET) for disease extent and disease activity in large-vessel vasculitis (LVV) and determine associations between imaging and clinical assessments.

METHODS

Patients with giant cell arteritis (GCA), Takayasu's arteritis (TAK) and comparators were recruited into a prospective, observational cohort. Imaging and clinical assessments were performed concurrently, blinded to each other. Agreement was assessed by per cent agreement, Cohen's kappa and McNemar's test. Multivariable logistic regression identified MRA features associated with PET scan activity.

RESULTS

Eighty-four patients (GCA=35; TAK=30; comparator=19) contributed 133 paired studies. Agreement for disease extent between MRA and PET was 580 out of 966 (60%) arterial territories with Cohen's kappa=0.22. Of 386 territories with disagreement, MRA demonstrated disease in more territories than PET (304vs82, p<0.01). Agreement for disease activity between MRA and PET was 90 studies (68%) with Cohen's kappa=0.30. In studies with disagreement, MRA demonstrated activity in 23 studies and PET in 20 studies (p=0.76). Oedema and wall thickness on MRA were independently associated with PET scan activity. Clinical status was associated with disease activity by PET (p<0.01) but not MRA (p=0.70), yet 35/69 (51%) patients with LVV in clinical remission had active disease by both MRA and PET.

CONCLUSIONS

In assessment of LVV, MRA and PET contribute unique and complementary information. MRA better captures disease extent, and PET scan is better suited to assess vascular activity. Clinical and imaging-based assessments often do not correlate over the disease course in LVV.

TRIAL REGISTRATION NUMBER

NCT02257866.

Recent Advances in Giant Cell Arteritis

PURPOSE OF REVIEW

Giant cell arteritis (GCA) is the most common systemic vasculitis. GCA is categorized as a granulomatous vasculitis of large and medium size vessels. Majority of the symptoms and signs of GCA result from involvement of the aorta and its branches intra- and extracranial. Temporal artery biopsy continues to be the cardinal diagnostic procedure despite new imaging modalities for diagnosing GCA with cranial involvement. Great advances in awareness have led to improvement in preventing irreversible vision loss due to early diagnosis.

RECENT FINDINGS

The cause of GCA has not been elucidated but major progress has been made in the knowledge of its pathogenesis leading to new therapeutic targets, particularly inhibition of interleukin 6. IL 6 plays a key role in the regulation of TH17/Tregs imbalance in GCA and appears to correlate with clinical disease activity in GCA. All of this has led to the first FDA (food and drug administration) approved treatment for GCA, Tocilizumab. Abatacept and Ustekinumab are promising targets for therapy in LVV but still need further research. This paper is a review of the recent progress in the understanding of GCA pathogenesis, diagnosis, treatment, and prognosis.

Surgical strategy for refractory aortitis

In some instances, we encounter cases suffered from inflammatory aortic diseases (aortitis) in Japan, some of which are at the active stages with systemic inflammation. Most of them are refractory with some technical difficulties of surgical treatment. The aortic wall, particularly, at the active stage, is too fragile to hold the surgical sutures. Consequently, the suture reinforcement with Teflon felt is required. In the late stage after surgery, false aneurysms on the suture line, that is, suture detachment potentially occur. To prevent such sequelae in the early and late phases, continuous (life-long) as well as perioperative inflammation control using corticosteroid as an initial drug and/or other immunosuppression agents. This decade, instead of the conventional open surgical repairs, endovascular treatments have widely spread, predominantly for stenotic aortic/arterial lesions. In particular, for more difficult patients suffered from more troublesome Behçet disease, endovascular treatments would have greater advantages to avoid more occasionally occurred pseudo-aneurysm on the other parts as well as the surgical suture lines. The key issues on surgical treatment for refractory aortitis are perioperative inflammation control including the long term with corticosteroid and/or immunosuppressive agents, appropriate open surgical or endovascular treatment approaches, and sufficient reinforcement of surgical suture lines.