title: Carotid baroreceptor stimulation blood pressure response mapped in patients undergoing carotid endarterectomy (C-Map study).
abstract: Continuous stimulation of the carotid baroreceptors has been shown to evoke a sustained systolic blood pressure (SBP) reduction in hypertensive subjects. This study conducted a detailed mapping of the SBP and heart rate response to electrical stimulus at different locations in the carotid sinus region in patients undergoing a carotid endarterectomy (CEA).
  
  
  
  The Carotid Sinus Autonomic Response Mapping (C-Map) Study is a multicenter, prospective, non-randomized, acute feasibility study conducted in 10 hypertensive subjects undergoing CEA. Electrode pairs were placed in multiple locations in the region of the carotid sinus for acute stimulation, and the tests were repeated after plaque removal and vessel repair.
  
  
  
  The configuration that elicited the largest pressure reduction in 8 of 10 patients was with the electrodes arranged longitudinally along the medial (in relation to the bifurcation) wall of the internal carotid artery (ICA) near the bifurcation (11.2±8.1mmHg, p<0.05). There was no difference in average maximum response pre vs. post plaque removal. Spontaneous baroreflex sensitivity increased from 6.0±3.2ms/mmHg pre-CEA to 8.2±5.4ms/mmHg post-CEA (p=0.040).
  
  
  
  Endarterectomy surgery did not affect maximal acute stimulation response but improved baroreflex sensitivity acutely. Acute extravascular baroreceptor stimulation (BRS) mapping demonstrated that blood pressure reductions are dependent on electrode location and orientation. In most subjects, the largest SBP reductions were elicited in the region of the medial wall of the ICA. This area can be targeted for future BRS lead design and implant.
authors.affiliation: University of California, San Diego, VA San Diego Healthcare System, Division of Vascular and Endovascular Surgery, San Diego, CA, United States. Electronic address: nikhil.kansal@steward.org.
authors.forename: Nikhil
authors.initials: N
authors.lastname: Kansal
authors.affiliation: The Cleveland Clinic Foundation, Department of Vascular Surgery, Cleveland, OH, United States.
authors.forename: Daniel G
authors.initials: DG
authors.lastname: Clair
authors.affiliation: Medtronic plc, Cardiac Rhythm and Heart Failure, Minneapolis, MN, United States.
authors.forename: Deborah A
authors.initials: DA
authors.lastname: Jaye
authors.affiliation: Medtronic plc, Cardiac Rhythm and Heart Failure, Minneapolis, MN, United States.
authors.forename: Avram
authors.initials: A
authors.lastname: Scheiner
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D017704:Baroreflex / Q000502:physiology*; D001794:Blood Pressure / Q000502:physiology*; D002346:Carotid Sinus / Q000473:pathology / Q000503:physiopathology / Q000601:surgery; D004558:Electric Stimulation / Q000295:instrumentation / Q000379:methods; D016894:Endarterectomy, Carotid; D005240:Feasibility Studies; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D006973:Hypertension / Q000188:drug therapy / Q000473:pathology / Q000503:physiopathology / Q000601:surgery; D008297:Male; D011311:Pressoreceptors / Q000502:physiology*; D011446:Prospective Studies
keywords: Baroreceptors; Baroreflex; Carotid sinus; Electrical stimulation; Endarterectomy; Hypertension