Upper limb ischemic preconditioning prevents recurrent stroke in intracranial arterial stenosis

OBJECTIVE: This study aims to evaluate protective effects of brief repetitive bilateral arm ischemic preconditioning (BAIPC) on stroke recurrence in patients with symptomatic atherosclerotic intracranial arterial stenosis (IAS). METHODS: A total of 68 consecutive cases with symptomatic IAS, diagnosed by imaging, were enrolled in this prospective and randomized study. All patients received standard medical management. Patients in the BAIPC group (n = 38) underwent 5 brief cycles consisting of bilateral upper limb ischemia followed by reperfusion. The BAIPC procedure was performed twice daily over 300 consecutive days. Incidence of recurrent stroke and cerebral perfusion status in BAIPC-treated patients were compared with the untreated control group (n = 30). RESULTS: In the control group, incidence of recurrent stroke at 90 and 300 days were 23.3% and 26.7%, respectively. In the BAIPC group, incidence of recurrent stroke was reduced to 5% and 7.9% at 90 and 300 days (p < 0.01), respectively. The average time to recovery (modified Rankin Scale score 0-1) was also shortened by BAIPC. Cerebral perfusion status, measured by SPECT and transcranial Doppler sonography, improved remarkably in BAIPC-treated brain than in control (p < 0.01). CONCLUSION: This study provides a proof-of-concept that BAIPC may be an effective way to improve cerebral perfusion and reduce recurrent strokes in patients with IAS. Further investigation of this therapeutic approach is warranted as some patients were excluded after randomization.