Abstract Background and aims Cerebral autoregulation maintains brain perfusion despite blood pressure fluctuations. Our aim is to identify clinical variables associated with dynamic cerebral autoregulation (dCA) early after a successfully treated ischaemic stroke. Methods This prospective single-centre pilot study enrolled patients with MCA ischaemic stroke treated with effective recanalisation (mTICI ≥2b). Within 24 hours of thrombectomy, bilateral transcranial Doppler and continuous blood pressure monitoring were performed. dCA was assessed using Transfer Function Analysis by an in-house software compliant with CARNet guidelines. Univariable and multivariable linear regression models were used to explore associations with Very Low Frequency (VLF) phase shift (PS). Results Twenty-six patients were included (median age 70 years; 65% male; median baseline NIHSS 15). In multivariable models, age emerged as the main determinant of VLF-PS (estimate −0.90 per year, 95% CI −1.55 to −0.26; p=0.008). Mean flow velocity (MFV) ratio (stroke/contralateral side) was not independently associated with VLF phase shift; however, a significant interaction between age and MFV ratio was observed (p=0.049), indicating that flow asymmetry was associated with lower PS predominantly in older patients. Age was not associated with MFV ratio. MFV ratio 1.3 (i.e. ≥30% higher velocity in the treated side) showed a borderline independent association with reduced VLF-PS (estimate −19.7 degrees, 95% CI −40.6 to 1.1; p=0.062). A trend toward higher VLF-PS was observed in patients with hypertension (p=0.082). Conclusions Early impairment of dCA after successful thrombectomy is primarily age-related. Post-reperfusion flow asymmetry (hyperperfusion) seems associated with worse autoregulation, mainly in older patients, potentially reflecting delayed adaptation of vasodilatory mechanisms after recanalisation. Conflict of interest Matteo Paolucci: nothing to disclose; Giacomo Urbinati: nothing to disclose; Ludovica Migliaccio: nothing to disclose; Mauro Gentile: nothing to disclose; Giorgia Arnone: nothing to disclose; Stefano Forlivesi: nothing to disclose; Andrea Zini: received funding for the study by Fondazione Carisbo 2023
Paolucci et al. (Fri,) studied this question.