Different giant cell arteritis phenotypes may present distinct types of ischaemic complications

To determine if the subtype of vascular ultrasound (US) presentation is associated with different types of ischaemic complications (IC) in giant cell arteritis (GCA). Retrospective observational analysis of GCA clinically confirmed patients referred to US fast-track clinics at two centres. All patients underwent baseline US of cranial and extracranial arteries (carotid, subclavian and axillary). Two patterns of IC were analysed: the occurrence of acute anterior ischaemic optic neuropathy (AION) or the presence of a non-AION pattern (including stroke, acute coronary syndrome, pulmonary embolism or peripheral artery disease) at diagnosis and in the following 3 months, excluding other potentially implicated causes. Of 188 clinically confirmed GCA patients, 43 (22.9%) had IC: 24 (12.8%) AION and 19 (10.1%) non-AION. Patients with AION more often exhibited US cranial involvement versus those with non-AION IC and without IC (100%, 63.2%, and 79.3%, respectively; p=0.009). Patients with AION less frequently presented signs of US large vessel (LV)-GCA than those with non-AION IC and without IC (25%, 63.2% and 55.2%, respectively; p=0.014). Patients with previous polymyalgia rheumatica (PMR) (p=0.049) or concomitant PMR symptoms at the time of diagnosis (p=0.014) showed less frequent AION. In contrast, patients with non-AION IC more frequently had positive LV-GCA US findings vs the other two groups (63.2%, 25% and 55.2%, respectively; p=0.014). The subtype of vascular US presentation influences the IC in GCA. US cranial-GCA patients more frequently present AION, while predominantly US LV-GCA more frequently exhibit non-AION IC.