Early nimodipine treatment in reversible cerebral vasoconstriction syndrome: a serial transcranial Doppler study

Abstract Background Although nimodipine is commonly used to treat reversible cerebral vasoconstriction syndrome (RCVS), its disease-modifying effects are not yet understood. We aimed to investigate the effect of nimodipine and treatment initiation timing on the prevention of worsened vasoconstriction. Methods We prospectively recruited patients with recent-onset (within 3 weeks of the first thunderclap headache), angiogram-proven RCVS. All participants underwent transcranial Doppler (TCD) examination to evaluate the mean flow velocities (MFVs) of the bilateral middle cerebral arteries at baseline and were serially followed-up after 10, 20, 30, and 90 days. Oral nimodipine treatment was initiated after the baseline TCD study, and patients were split into early and late treatment groups based on the time from onset to initial nimodipine administration. To estimate the worsening of vasoconstriction, we calculated the area of total time spent with MFVs above the baseline value (“MFV area”). We tested the correlation between the number of days from onset to treatment initiation and MFV area and performed linear regression analysis to examine the independent association between earlier treatment and MFV area. Results A total of 32 patients with RCVS (mean age: 51.5 ± 10.3 years; 91% female) completed this study. Baseline TCD assessment was performed at a mean of 7.1 ± 4.2 days after thunderclap headache onset. We observed that earlier treatment with nimodipine correlated with reduced MFV area (r = 0.37, p = 0.038). Furthermore, this association remained significant after adjusting for other clinical variables (regression coefficient 0.673, adjusted p = 0.023) in the multivariable linear regression. Conclusions Early oral nimodipine treatment prevents worsening of vasoconstriction, suggesting that nimodipine may have a disease-modifying effect in RCVS treatment.