Cerebral hemodynamics and baroreflex sensitivity after carotid artery stenting Hsu L-C, Chang F-C, Kuo TBJ, Wong WJ, Hu H-H. Cerebral hemodynamics and baroreflex sensitivity after carotid artery stenting. Acta Neurol Scand: 2013: 127: 46–52. © 2012 John Wiley & Sons A/S. Objectives – The long-term hemodynamic effects of carotid angioplasty and stenting (CAS) are unclear. We performed a longitudinal study to investigate the variations in cerebral hemodynamics in patients undergoing CAS. Materials and methods – We performed prospective evaluation of 63 symptomatic male patients (19 patients had transient ischemic attack and 44 had minor stroke; mean age: 77.3 ± 6.3 years [range: 51–86]). The mean blood flow velocities (MBFV) and pulsatility index (PI) of the middle cerebral arteries (MCA) on both sides were evaluated using transcranial color- coded Doppler (TCCD) ultrasonography. Cardiac autonomic activities were evaluated by measuring baroreflex sensitivity (BRS). All parameters were measured at baseline prior to CAS and at 1, 3, 6, and 12 months after CAS. Results – The preoperative MBFV and PI of the ipsilateral MCA were significantly lower than those of the contralateral side. However, after CAS, MBFV in the ipsilateral MCA increased significantly until 2 weeks after stenting, after which the MBFV gradually decreased and remained stable for 1 year after CAS. Further, we observed a nonsignificant increase in MBFV in the contralateral MCA after CAS. In contrast to the MBFV, the BRS values decreased significantly 1 month after stenting and returned to baseline levels 6 months after CAS. Conclusions – Patients with CAS showed improved global cerebral hemodynamic status. However, the BRS did not normalize initially, and baseline value was achieved at 6 months after stenting. L.-C. Hsu 1,2 , F.-C. Chang 2,3 , T. B. J. Kuo 4 , W.-J. Wong 1,2 , H.-H. Hu 1,2 1 Department of Neurology, Taipei Veterans General Hospital, Taipei, Taiwan; 2 School of Medicine, National Yang-Ming University, Taipei, Taiwan; 3 Department of Radiology, Taipei Veterans General Hospital, National Yang-Ming University, Taipei, Taiwan; 4 Institute of Brain Science, National Yang- Ming University, Taipei, Taiwan Key words: baroreflex sensitivity; carotid stenosis; stent; transcranial Doppler H.-H. Hu, Department of Neurology, Taipei Veterans General Hospital, 201 Sec. 2, Shih-Pai Road, Taipei 11217, Taiwan, ROC Tel.: +886 2 2875 7046 Fax: +886 2 2873 9241 e-mail: hhhu@vghtpe.gov.tw Accepted for publication April 11, 2012 Introduction Atherosclerotic carotid stenosis is associated with impaired neurological outcome and high morbidi- ties (1–3). Carotid angioplasty and stenting (CAS) has emerged as a potential therapeutic alternative to carotid endarterectomy (CEA) for patients with severe internal carotid artery (ICA) stenosis; favorable results in terms of subsequent stroke and death rate have been obtained in CAS patients (4–6). Several studies have shown hemo- dynamic changes after CEA (7–12). However, studies on long-term hemodynamic changes and their association with hyperperfusion syndrome (HS) after CAS are relatively rare. Cerebral hemodynamics can be evaluated using transcranial color-coded Doppler (TCCD) ultrasonography, which is a simple, noninvasive tool for the assessment of intracranial blood flow and cerebral perfusion (13–15). Several studies have shown hemodynamic changes after CAS, such as increased blood flow velocities and improved cerebral vasoreactivity in the middle cerebral artery (MCA) (16–20). How- ever, most of these studies involved only short- term evaluations, the longest being 2–4 months after CAS (18). Baroreflex is a key regulatory mechanism in the short-term control of cardiovascular auto- nomic activity, that is, blood pressure and heart rate variability (HRV). Baroreflex sensitivity (BRS) is used to measure the performance of baroreflex, which is defined as changes in the heart rate in response to changes in systolic blood 46 Acta Neurol Scand 2013: 127: 46–52 DOI: 10.1111/j.1600-0404.2012.01679.x Ó 2012 John Wiley & Sons A/S ACTA NEUROLOGICA SCANDINAVICA