Objective Patients with carotid stenosis or occlusion may be at increased risk for stroke during air travel. Records from the Carotid Occlusion Surgery Study (COSS), a randomised trial of surgical revascularisation for complete carotid artery occlusion and haemodynamic ischaemia, were examined for evidence of stroke related to air travel.

Methods COSS subjects who travelled by aeroplane to a regional Positron Emission Tomography (PET) centre for a screening of cerebrovascular haemodynamic evaluation were identified. Maximum altitude and total flight time were estimated based on the distance between origin and destination. Ischaemic events were determined by a structured telephone interview within 24 h of travel. Patient demographics, comorbidities, oxygen extraction fraction (OEF) data and 24 h interview responses were recorded.

Results Seventy-seven patients with symptomatic carotid occlusion travelled by aeroplane to a single PET centre (174 flights). Fifty-two (67.5%) were men and 25 (32.5%) were women. The average age was 58.7±1.4 years. Twenty-seven patients (35.1%) demonstrated evidence of ipsilateral haemodynamic cerebral ischaemia as measured by PET OEF, while 50 (64.9%) had normal OEF. Patients flew an average distance of 418.9±25.9 miles for 107.1±4.7 min per trip. No patient reported symptoms of a transient ischaemic attack or stroke during or within 24 h after aeroplane travel (95% CI 0% to 2.0%).

Conclusions The risk of stroke as a consequence of air travel is low, even in a cohort of patients at high risk for future stroke owing to haemodynamic impairment. These patients with symptomatic carotid occlusion should not be discouraged from air travel.