Background/Purpose:

Patients with Takayasu’s arteritis (TAK) can experience symptoms due to vascular inflammation or vascular damage. The study objective was to investigate whether specific vascular symptoms are more closely associated with vascular disease activity measured by ¹⁸F-fluorodeoxyglucose positron emission tomography (FDG-PET) or vascular damage assessed by magnetic resonance angiography (MRA).

Methods:

Patients with TAK were recruited into a prospective observational cohort. Participants underwent clinical assessment and standardized imaging assessment (FDG-PET and MRA) within a 24-hour period, blinded to each other. Vascular disease activity was defined as arterial FDG uptake > liver by visual assessment. Vascular damage was defined as either stenosis, occlusion, or aneurysm in specific arterial territories on MRA. Clinical symptoms present on the day of evaluation (carotidynia; frontal headache; arm claudication) were compared to imaging findings in corresponding arterial territories. Generalized symptoms (headache; dizziness; history of CNS event defined as TIA/stroke or syncope) were studied in association with the number of affected neck vessels by MRA. Performance characteristics were calculated and the association between clinical symptoms and imaging features was assessed by Fisher’s exact test.

Results:

51 participants contributed data from 92 study visits. For FDG-PET, the sensitivity (SN) of specific clinical symptoms ranged from 16% to 33% and specificity (SP) from 74% to 98%. For MRA the SN of the same symptoms ranged from 6% to 71% and SP from 79% to 100%. Details of specific associations are shown in the Table. Carotidynia was significantly associated with carotid activity by FDG-PET (p<0.01) but not carotid damage by MRA (p=0.18). Frontal headache was significantly associated with both carotid activity by FDG-PET (p<0.01) and carotid damage by MRA (p=0.04). Arm claudication was significantly associated with subclavian damage by MRA (p<0.01) but not subclavian activity by FDG-PET (p=0.47). Headache (p=0.02) and history of CNS events (p<0.01) was significantly associated with damage to ≥2 neck arteries, and dizziness (p<0.01) was associated with damage to ≥ 3 neck arteries.

Conclusion:

Absence of clinical symptoms does not rule out vascular abnormalities by FDG-PET or MRA, but presence of symptoms is often associated with imaging abnormalities. Certain features are more closely associated with FDG-PET activity while others are more closely linked to vascular damage. Complaints of headache, dizziness, and CNS events are associated with the burden of vascular pathology in the neck arteries. These findings have direct clinical implications and may inform the development of disease activity indices in TAK.