carotid sinus


Summary: The dilated portion of the common carotid artery at its bifurcation into external and internal carotids. It contains baroreceptors which, when stimulated, cause slowing of the heart, vasodilatation, and a fall in blood pressure.

Top Publications

  1. Klawe J, Tafil Klawe M, Sikorski W, Szajnoch W, Jeske K. Age-related circadian variations of cardiac and respiratory components of the carotid baroreflex in humans. J Physiol Pharmacol. 2004;55 Suppl 3:83-8 pubmed
    ..Two neck-chambers were used to produce a brief suction, applied to carotid sinus regions, activating the carotid baroreceptor...
  2. Tan M, Newton J, Reeve P, Murray A, Chadwick T, Parry S. Results of carotid sinus massage in a tertiary referral unit--is carotid sinus syndrome still relevant?. Age Ageing. 2009;38:680-6 pubmed publisher
    b>carotid sinus hypersensitivity (CSH) is associated with syncope, drop attacks and unexplained falls in older people. However, a recent study has also reported a prevalence of 35% in asymptomatic community-dwelling older people.
  3. Parry S, Steen N, Bexton R, Tynan M, Kenny R. Pacing in elderly recurrent fallers with carotid sinus hypersensitivity: a randomised, double-blind, placebo controlled crossover trial. Heart. 2009;95:405-9 pubmed publisher
    While carotid sinus syndrome (CSS) is traditionally defined by the association of carotid sinus hypersensitivity (CSH) with syncope, uncertainty remains over the role, if any, of complex pacing in patients with CSH and unexplained or ..
  4. Miller V, Kenny R, Slade J, Oakley A, Kalaria R. Medullary autonomic pathology in carotid sinus hypersensitivity. Neuropathol Appl Neurobiol. 2008;34:403-11 pubmed
    b>Carotid sinus hypersensitivity (CSH) is an ageing-related autonomic disorder, rarely occurring before the age of 50 years but increasing in incidence thereafter...
  5. Conde S, Obeso A, Gonzalez C. Low glucose effects on rat carotid body chemoreceptor cells' secretory responses and action potential frequency in the carotid sinus nerve. J Physiol. 2007;585:721-30 pubmed
    ..glucose homeostasis, but this role has been questioned on the basis of a lack of effect of low glucose on the carotid sinus nerve activity...
  6. Coplan N. Carotid sinus hypersensitivity and syncope: cause/effect or true/true/unrelated. Arch Intern Med. 2006;166:491-2 pubmed
  7. Kenny R, Richardson D. Carotid sinus syndrome and falls in older adults. Am J Geriatr Cardiol. 2001;10:97-9 pubmed
    ..we undertook a prospective, explanatory, single-center study of cardiac pacing for falls in patients with carotid sinus syndrome in a consecutive series of over 56,000 adult visitors to an emergency department...
  8. Tordoir J, Scheffers I, Schmidli J, Savolainen H, Liebeskind U, Hansky B, et al. An implantable carotid sinus baroreflex activating system: surgical technique and short-term outcome from a multi-center feasibility trial for the treatment of resistant hypertension. Eur J Vasc Endovasc Surg. 2007;33:414-21 pubmed
    To assess perioperative outcomes and blood pressure (BP) responses to an implantable carotid sinus baroreflex activating system being investigated for the treatment of resistant hypertension.
  9. Cole C, Zuckerman J, Levine B. Carotid sinus "irritability" rather than hypersensitivity: a new name for an old syndrome?. Clin Auton Res. 2001;11:109-13 pubmed
    b>Carotid sinus hypersensitivity (CSH) is a well-described cause of syncope, resulting in bradycardia and/or hypotension in response to neck pressure...

More Information


  1. Kawada T, Shimizu S, Li M, Kamiya A, Uemura K, Sata Y, et al. Contrasting effects of moderate vagal stimulation on heart rate and carotid sinus baroreflex-mediated sympathetic arterial pressure regulation in rats. Life Sci. 2011;89:498-503 pubmed publisher
    To examine whether moderate efferent vagal nerve stimulation (VNS) attenuates the carotid sinus baroreflex-mediated arterial pressure (AP) regulation via its antagonism to the sympathetic system.
  2. Sutherland J, Stobie P, Swarup V, Tierney S, Lin A, Burke M. Hypersensitive carotid sinus syndrome due to neurofibromatosis-1 and manifested by repeated episodes of syncope. Pacing Clin Electrophysiol. 2004;27:1571-3 pubmed
    ..Imaging of her head and neck demonstrated a large neurofibroma enveloping her right carotid sinus without vessel occlusion or evidence of malignancy. An event recorder documented asystole...
  3. Ng M, Sica D, Frishman W. Rheos: an implantable carotid sinus stimulation device for the nonpharmacologic treatment of resistant hypertension. Cardiol Rev. 2011;19:52-7 pubmed publisher
    ..resistant to multidrug therapy, by activating the carotid baroreflex through electrical stimulation of the carotid sinus wall...
  4. Sabbah H, Gupta R, Imai M, Irwin E, Rastogi S, Rossing M, et al. Chronic electrical stimulation of the carotid sinus baroreflex improves left ventricular function and promotes reversal of ventricular remodeling in dogs with advanced heart failure. Circ Heart Fail. 2011;4:65-70 pubmed publisher
    Autonomic abnormalities exist in heart failure and contribute to disease progression. Activation of the carotid sinus baroreflex (CSB) has been shown to reduce sympathetic outflow and augment parasympathetic vagal tone...
  5. Krediet C, Parry S, Jardine D, Benditt D, Brignole M, Wieling W. The history of diagnosing carotid sinus hypersensitivity: why are the current criteria too sensitive?. Europace. 2011;13:14-22 pubmed publisher
    The carotid sinus syndrome and carotid sinus hypersensitivity (CSH) are closely related disorders. The first is characterized by syncope triggered by manipulation of the carotid sinus in daily life (e.g. shaving)...
  6. Illig K, Levy M, Sanchez L, Trachiotis G, Shanley C, Irwin E, et al. An implantable carotid sinus stimulator for drug-resistant hypertension: surgical technique and short-term outcome from the multicenter phase II Rheos feasibility trial. J Vasc Surg. 2006;44:1213-1218 pubmed
    ..Electrical stimulation of the carotid sinus baroreflex system has been shown to produce significant chronic blood pressure decreases in animals...
  7. Sloand J, Illig K, Bisognano J. Improved control of resistant hypertension with device-mediated electrical carotid sinus baroreflex stimulation. J Clin Hypertens (Greenwich). 2007;9:716-9 pubmed
  8. Claesson J, Kristensson B, Edvardsson N, Wahrborg P. Less syncope and milder symptoms in patients treated with pacing for induced cardioinhibitory carotid sinus syndrome: a randomized study. Europace. 2007;9:932-6 pubmed
    The aim of this study was to examine the effect on symptoms in patients with induced cardioinhibitory carotid sinus syndrome (ICSS) when treated or not treated with a pacemaker.
  9. Blessing W, Yu Y, Nalivaiko E. Medullary projections of rabbit carotid sinus nerve. Brain Res. 1999;816:405-10 pubmed
    In New Zealand white rabbits, cholera-toxin HRP was injected into the carotid sinus nerve just proximal to the carotid sinus. After survival periods of 3-5 days the rabbits were anesthetized and the brain fixed with aldehyde solution...
  10. Humm A, Mathias C. Abnormal cardiovascular responses to carotid sinus massage also occur in vasovagal syncope - implications for diagnosis and treatment. Eur J Neurol. 2010;17:1061-7 pubmed publisher
    b>Carotid sinus massage (CSM) is commonly used to identify carotid sinus hypersensitivity (CSH) as a possible cause for syncope, especially in older patients...
  11. Humm A, Mathias C. Unexplained syncope--is screening for carotid sinus hypersensitivity indicated in all patients aged >40 years?. J Neurol Neurosurg Psychiatry. 2006;77:1267-70 pubmed
    To determine the frequency, age distribution and clinical presentation of carotid sinus hypersensitivity (CSH) among 373 patients (age range 15-92 years) referred to two autonomic referral centres during a 10-year period.
  12. Shu H, Wang B, Wang S, Yao W, Huang H, Zhou Z, et al. IL-1beta inhibits IK and increases [Ca2+]i in the carotid body glomus cells and increases carotid sinus nerve firings in the rat. Eur J Neurosci. 2007;25:3638-47 pubmed test whether IL-1beta could stimulate the CB glomus cells and alter the discharge properties in the carotid sinus nerve, the afferent nerve innervating the organ...
  13. Sanchez L, Illig K, Levy M, Trachiotis G, Shanley C, Irwin E, et al. Implantable carotid sinus stimulator for the treatment of resistant hypertension: local effects on carotid artery morphology. Ann Vasc Surg. 2010;24:178-84 pubmed publisher
    The Rheos System is a chronically implanted carotid sinus baroreflex activating system with a pulse generator and bilateral perivascular carotid sinus leads (CSLs) that is being evaluated in prospective clinical trials for the treatment ..
  14. Jordan J, Heusser K, Brinkmann J, Tank J. Electrical carotid sinus stimulation in treatment resistant arterial hypertension. Auton Neurosci. 2012;172:31-6 pubmed publisher
    ..control of sympathetic activity and blood pressure providing an impetus for the development of electrical carotid sinus stimulators...
  15. Bin Jaliah I, Maskell P, Kumar P. Indirect sensing of insulin-induced hypoglycaemia by the carotid body in the rat. J Physiol. 2004;556:255-66 pubmed
    ..1 mmoll(-1)) significantly increased spontaneous ventilation in sham-operated animals but not in bilateral carotid sinus nerve sectioned (CSNX) animals...
  16. Al Rawi P, Sigaudo Roussel D, Gaunt M. Effect of lignocaine injection in carotid sinus on baroreceptor sensitivity during carotid endarterectomy. J Vasc Surg. 2004;39:1288-94 pubmed
    ..carotid endarterectomy (CEA), by investigating intraoperative hemodynamic changes induced by intraluminal carotid stretch stimulation, before and after application of local anesthetic to the adventitial layer of the carotid sinus region.
  17. Clarke J, Daly M, Ead H, Hennessy E. The carotid body of the spontaneous insulin-dependent diabetic rat. Braz J Med Biol Res. 1999;32:85-91 pubmed
    ..In one diabetic specimen the carotid sinus nerve showed signs of diabetic neuropathy, axonal swelling and intramyelinic oedema...
  18. Conde S, Monteiro E, Rigual R, Obeso A, Gonzalez C. Hypoxic intensity: a determinant for the contribution of ATP and adenosine to the genesis of carotid body chemosensory activity. J Appl Physiol (1985). 2012;112:2002-10 pubmed publisher
    ..To test this hypothesis we measured carotid sinus nerve (CSN) activity in response to moderate and intense hypoxic stimuli (7 and 0% O(2)) in the absence and in ..
  19. Toorop R, Scheltinga M, Moll F, Bleys R. Anatomy of the carotid sinus nerve and surgical implications in carotid sinus syndrome. J Vasc Surg. 2009;50:177-82 pubmed publisher
    The carotid sinus syndrome (CSS) is characterized by syncope and hypotension due to a hypersensitive carotid sinus located in the carotid bifurcation...
  20. Takata T, Wasmund S, Smith M, Li J, Joglar J, Banks K, et al. Serotonin reuptake inhibitor (Paxil) does not prevent the vasovagal reaction associated with carotid sinus massage and/or lower body negative pressure in healthy volunteers. Circulation. 2002;106:1500-4 pubmed
    ..We hypothesized that Paxil prevents neurally mediated syncope (NMS) by attenuating the sympathoinhibition and vagotonia associated with a vasovagal reaction...
  21. Kameda Y, Ito M, Nishimaki T, Gotoh N. FRS2 alpha 2F/2F mice lack carotid body and exhibit abnormalities of the superior cervical sympathetic ganglion and carotid sinus nerve. Dev Biol. 2008;314:236-47 pubmed publisher
    ..The number of carotid sinus nerve fibers that reached the carotid bifurcation region was markedly decreased, and baroreceptor fibers ..
  22. Parry S, Richardson D, O Shea D, Sen B, Kenny R. Diagnosis of carotid sinus hypersensitivity in older adults: carotid sinus massage in the upright position is essential. Heart. 2000;83:22-3 pubmed
    To assess the diagnostic value of supine and upright carotid sinus massage in elderly patients.
  23. Tan M, Kenny R, Chadwick T, Kerr S, Parry S. Carotid sinus hypersensitivity: disease state or clinical sign of ageing? Insights from a controlled study of autonomic function in symptomatic and asymptomatic subjects. Europace. 2010;12:1630-6 pubmed publisher
    This study sought to improve the currently limited understanding of the pathophysiology of carotid sinus hypersensitivity (CSH) by comparing autonomic function measured by heart rate variability (HRV) and baroreflex sensitivity ..
  24. Bollmann A, Wodarz K, Esperer H, Toepffer I, Klein H. Response of atrial fibrillatory activity to carotid sinus massage in patients with atrial fibrillation. Pacing Clin Electrophysiol. 2001;24:1363-8 pubmed
    In some cases carotid sinus massage (CSM) may induce AF, whereas it may terminate AF in others. The purpose of this study was to investigate the influence of CSM on atrial fibrillatory frequency using spectral analysis of the surface ECG...
  25. Takahashi T, Obata N, Sugawara N, Fujita K, Oikawa K, Yoshimoto M, et al. Carotid sinus syncope in a patient with relapsed cervical lymphoma. Int J Hematol. 2006;84:92-3 pubmed
  26. Roux J, Peyronnet J, Pascual O, Dalmaz Y, Pequignot J. Ventilatory and central neurochemical reorganisation of O2 chemoreflex after carotid sinus nerve transection in rat. J Physiol. 2000;522 Pt 3:493-501 pubmed
    ..early time course and pattern of hypoxic ventilatory response (HVR) recovery following irreversible bilateral carotid sinus nerve transection (CSNT)...
  27. Ryan D, Nick S, Colette S, Roseanne K. Carotid sinus syndrome, should we pace? A multicentre, randomised control trial (Safepace 2). Heart. 2010;96:347-51 pubmed publisher
    Cardioinhibitory carotid sinus hypersensitivity (CICSH) is highly prevalent among older people with falls.
  28. Leftheriotis G, Dupuis J, Victor J, Saumet J. Effect of cardiac pacing on peripheral and cerebral hemodynamics in patients with carotid sinus syndrome. Am J Cardiol. 1999;83:974-7, A10 pubmed
    The effect of dual-chamber detected atrioventricular pacing mode alone and combined with rate-drop response reduced vasodepression and cerebral hypoperfusion induced by carotid massage in patients with carotid sinus syndrome.
  29. Querry R, Smith S, Strømstad M, Ide K, Secher N, Raven P. Anatomical and functional characteristics of carotid sinus stimulation in humans. Am J Physiol Heart Circ Physiol. 2001;280:H2390-8 pubmed
    Transmission characteristics of pneumatic pressure to the carotid sinus were evaluated in 19 subjects at rest and during exercise...
  30. Davies A, Steen N, Kenny R. Carotid sinus hypersensitivity is common in older patients presenting to an accident and emergency department with unexplained falls. Age Ageing. 2001;30:289-93 pubmed
    To determine the prevalence of carotid sinus hypersensitivity and orthostatic hypotension in older patients with non-accidental falls attending an accident and emergency department.
  31. Puggioni E, Guiducci V, Brignole M, Menozzi C, Oddone D, Donateo P, et al. Results and complications of the carotid sinus massage performed according to the "method of symptoms". Am J Cardiol. 2002;89:599-601 pubmed
  32. Claassen J, Jansen R. Carotid sinus syndrome: looking sideways is sufficient cause for syncope. J Am Geriatr Soc. 2006;54:188-9 pubmed
  33. Wang R, Xu F, Zhuang J, Zhang C. Carotid sinus nerve is involved in cardiorespiratory responses to intracarotid injection of capsaicin in the rat. J Appl Physiol (1985). 2006;100:60-6 pubmed
    The carotid sinus nerve (CSN), important in cardiorespiratory modulation, mainly contains C fibers (CSCFs)...
  34. Roy A, Mandadi S, Fiamma M, Rodikova E, Ferguson E, Whelan P, et al. Anandamide modulates carotid sinus nerve afferent activity via TRPV1 receptors increasing responses to heat. J Appl Physiol (1985). 2012;112:212-24 pubmed publisher
    ..that independent perfusion of carotid arteries with supraphysiological concentrations of ANA strongly excites carotid sinus nerve afferents and that this activity is sufficient to increase phrenic activity...
  35. Kumar N, Thomas A, Mudd P, Morris R, Masud T. The usefulness of carotid sinus massage in different patient groups. Age Ageing. 2003;32:666-9 pubmed
    to determine the positive yield of carotid sinus massage in different patient groups: unexplained syncope, falls, dizziness and controls.
  36. Kawada T, Inagaki M, Takaki H, Sato T, Shishido T, Tatewaki T, et al. Counteraction of aortic baroreflex to carotid sinus baroreflex in a neck suction model. J Appl Physiol (1985). 2000;89:1979-84 pubmed
    Although neck suction has been widely used in the evaluation of carotid sinus baroreflex function in humans, counteraction of the aortic baroreflex tends to complicate any interpretation of observed arterial pressure (AP) response...
  37. Mohaupt M, Schmidli J, Luft F. Management of uncontrollable hypertension with a carotid sinus stimulation device. Hypertension. 2007;50:825-8 pubmed
  38. Xiao L, Wu Y, Zhang H, Liu Y, He R. Hydrogen sulfide facilitates carotid sinus baroreflex in anesthetized rats. Acta Pharmacol Sin. 2006;27:294-8 pubmed
    To study effects of hydrogen sulfide (H2S) on the carotid sinus baroreflex (CSB).
  39. Leftheriotis G, Rozak P, Dupuis J, Victor J, Tadei A, Saumet J. Cerebral hemodynamics during carotid massage in patients with carotid sinus syndrome. Pacing Clin Electrophysiol. 1998;21:1885-92 pubmed
    ..Doppler has been investigated during carotid massage in 11 patients (62-87 years, mean age 72) with carotid sinus syndrome. The patients were tested in the OOO mode (n = 11) with six tested in the DDD mode...
  40. Marek W, Muckenhoff K, Prabhakar N. Significance of pulmonary vagal afferents for respiratory muscle activity in the cat. J Physiol Pharmacol. 2008;59 Suppl 6:407-20 pubmed
    ..and lung inflations were performed during hyperoxic normocapnia, during electrical stimulation of one carotid sinus nerve (CSN) or the intracranial medullary chemosensitivity (MCS), during hypercapnia or the combination of CSN ..
  41. Leisch F, Kerschner K, Hofmann R, Steinwender C, Grund M, Bibl D, et al. Carotid sinus reactions during carotid artery stenting: predictors, incidence, and influence on clinical outcome. Catheter Cardiovasc Interv. 2003;58:516-23 pubmed
    b>Carotid sinus reactions (CSR), defined as asystole >/= 3 sec and hypotension (systolic blood pressure </= 90 mm Hg), are frequent events during carotid artery stenting (CAS)...
  42. Milton J, Lee T, Jackson S. Determinants of a positive response to carotid sinus massage and head-up tilt testing. Eur J Intern Med. 2009;20:709-11 pubmed publisher
    Orthostatic hypotension (OH) and carotid sinus hypersensitivity (CSH) are common causes of syncope in older people...
  43. Kerr S, Pearce M, Brayne C, Davis R, Kenny R. Carotid sinus hypersensitivity in asymptomatic older persons: implications for diagnosis of syncope and falls. Arch Intern Med. 2006;166:515-20 pubmed
    b>Carotid sinus hypersensitivity is the most commonly reported cause of falls and syncope in older persons. Recent guidelines recommend 5 to 10 seconds of carotid sinus massage in supine and upright positions with beat-to-beat monitoring...
  44. Parry S, Baptist M, Gilroy J, Steen N, Kenny R. Central alpha2 adrenoceptors and the pathogenesis of carotid sinus hypersensitivity. Heart. 2004;90:935-6 pubmed
  45. Ogoh S, Fadel P, Nissen P, Jans Ø, Selmer C, Secher N, et al. Baroreflex-mediated changes in cardiac output and vascular conductance in response to alterations in carotid sinus pressure during exercise in humans. J Physiol. 2003;550:317-24 pubmed
    ..Acute changes in carotid sinus transmural pressure were evoked using 5 s pulses of neck pressure (NP) and neck suction (NS) from +40 to -80 ..
  46. McDonald D. Morphology of the rat carotid sinus nerve. I. Course, connections, dimensions and ultrastructure. J Neurocytol. 1983;12:345-72 pubmed
    An analysis of the morphology of the carotid sinus nerve in 39 rats revealed that the nerve emerged from the glossopharyngeal nerve (nerve IX) 0.6-1.0 mm beyond the distal extent of the petrosal ganglion...
  47. Cordina S, Qureshi A. Syncope and carotid artery stenosis. Minerva Med. 2009;100:321-7 pubmed
    The carotid sinus plays an important role in systemic blood pressure regulation. The baroreceptor mechanism that underlies this physiological process is affected by underlying disease processes and therapeutic procedures...
  48. He L, Liu X, Chen J, Dinger B, Stensaas L, Fidone S. Modulation of chronic hypoxia-induced chemoreceptor hypersensitivity by NADPH oxidase subunits in rat carotid body. J Appl Physiol (1985). 2010;108:1304-10 pubmed publisher
    ..Our findings suggest that increased ROS production by NOX enzymes in type I cells dampens CH-induced hypersensitivity in carotid body chemoreceptors...
  49. Masson C. Carotid sinus hypersensitivity: an age-related phenomenon. J Neurol Neurosurg Psychiatry. 2006;77:1207 pubmed
  50. Chen H, Chang K, Kang B, Liu D. Baroreflex adaptation and resetting on the control of arterial pressure. Chin J Physiol. 1990;33:19-30 pubmed
    In anesthetized and vagotomized dogs, the carotid sinuses were vascularly isolated to control and adjust the carotid sinus pressure (CSP)...
  51. Takahashi T, Osanai S, Nakano H, Ohsaki Y, Kikuchi K. Doxapram stimulates the carotid body via a different mechanism than hypoxic chemotransduction. Respir Physiol Neurobiol. 2005;147:1-9 pubmed
    ..Neither pinacidil nor levcromakalim affected the stimulatory effect of doxapram. We conclude that doxapram stimulates the carotid body via a different mechanism than hypoxic chemotransduction...
  52. Osborne R. Nonpulsatile carotid body tumor in a teenager. Ear Nose Throat J. 2005;84:133-4 pubmed
  53. Fuller D, Bavis R, Vidruk E, Wang Z, Olson E, Bisgard G, et al. Life-long impairment of hypoxic phrenic responses in rats following 1 month of developmental hyperoxia. J Physiol. 2002;538:947-55 pubmed
    ..To examine the central integration of carotid chemoafferent inputs, steady-state relationships between carotid sinus nerve (electrical) stimulation frequency and phrenic nerve activity were compared in aged control (n = 7) and ..