Recurrent Syncope Due to Carotid Sinus Hypersensitivity in Cerebral

Clinical/Scientific Note

Clinical & Translational Neuroscience January–June 2018: 1–3 ª The Author(s) 2018 Recurrent syncope due to carotid Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/2514183X18764788 sinus hypersensitivity in cerebral journals.sagepub.com/home/ctn atherosclerosis

Bjo¨rn Zo¨rner1,2, Jan Steffel2,3, Michael Linnebank1,2, and Alexander A Tarnutzer1,2

Abstract A 62-year-old female with a history of stroke due to cerebral arteriosclerosis suffered from recurrent fainting (<10s) provoked by rapid head movements up to four times per month for at least two years. There was no evidence of new strokes in repeated MRI and no high-grade vertebral artery stenosis on catheter angiography. Electroencephalography and cardiovascular workup were normal. Because fainting was head-position triggered, carotid massage was performed, demonstrating transient sinus arrest and carotid sinus syndrome (CSS) was diagnosed. After pacemaker implantation, episodes disappeared. Based on this case we discuss the diagnostic approach and also potential pitfalls and limitations of CSS.

Keywords Loss of consciousness, vertigo, cardiac arrhythmia, dizziness, pacemaker

Case description of the vertebral arteries bilaterally were not confirmed by catheter angiography (Figure 1(a) and (b)) and on the inter- A 62-year old female podiatrist with a history of stroke nal carotid arteries no significant (i.e. 50%) stenoses were due to left-sided internal carotid artery stenosis at age noted either. Finally, right-sided carotid sinus massage was 59 years suffered from short (lasting seconds), recurrent performed in supine position demonstrating transient sinus episodes with dizziness and sudden loss of consciousness arrest for about 5 s (Figure 1c), and a cardioinhibitory up to four times a month for a period of at least 2 years. carotid sinus syndrome (CSS)1 was diagnosed. There was Events were provoked by rapid head movements, for no clinical evidence for cerebral ischemia provoked by the example, during walking, but also at rest. Typically, faint- carotid massage. After pacemaker implantation (DDD ing occurred when she worked overhead with her arms type, i.e. with dual chamber pacing and sensing, both trig- elevated and the head reclined. For example, hanging up gered and inhibited mode),2 no further episodes occurred the laundry or taking things down from shelves triggered (11 months follow-up). the spells. Fall-relatedinjuriessuchasdeeplacerations at the head and the arms were linked to these transient losses of consciousness. Further consequences included social withdrawal, avoidance behavior, and the develop- 1 ment of depressive symptoms. Department of Neurology, University Hospital Zurich, Zurich, In repeated brain magnetic resonance imaging scans, Switzerland 2 University of Zurich, Zurich, Switzerland there was no evidence of recent cerebrovascular ischemia. 3 Department of Cardiology, University Hospital Zurich, Zurich, Electroencephalographys and cardiovascular workup Switzerland including electrocardiography (ECG) monitoring over 7 days, however, without recording a fainting spell, were Corresponding author: Alexander A Tarnutzer, Department of Neurology, University Hospital normal. Although initially postulated based on magnetic Zurich, Frauenklinikstr. 26, 8091 Zurich, Switzerland. resonance angiography and duplex, high-grade stenoses Email: [email protected]

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Figure 1. (a, b) Catheter angiography demonstrated minor stenosis (<30%) only of left VA and was otherwise normal. (c) ECGs before and after pacemaker implantation. Before treatment, carotid sinus massage triggered asystolia. After implantation, a pacemaker- triggered heartbeat was seen during carotid sinus massage. VA: vertebral artery.

CSS is a frequent cause of transient loss of conscious- lasting less than 3 s.6 In some cases, both asystole lasting ness affecting primarily subjects above the age of 50 years, more than 3 s and a drop in blood pressure of more than 50 with prevalence rates as high as 22–68% of all patients with mmHg can be observed; this condition has been termed unexplained syncope being reported.1,3 Associated factors mixed CSS.6 Noteworthy, neurologic and cardiovascular include hypertension, general atherosclerosis and coronary complications seem to be rare after carotid sinus massage heart disease,4 tight collars, neck tumors, and neck surgery/ and therapeutic consequences may be significant.1 Accord- irradiation may trigger the reflex.3 Neurodegenerative pro- ing to a recent review, neurologic complications due to cesses in the medulla oblongata and impaired function of cerebral embolism occur at a rate of approximately 1 in the baroreceptors in the internal carotid arteries were pos- 1000 patients, being transient in most cases.7 Nonetheless, tulated to be involved in its pathophysiology.1 However, persistent deficits may result in major disability8 or even the specific mechanisms leading to hypersensitivity of the death9 in selected cases. Contraindications for carotid sinus carotid sinus reflex are still largely unknown.5 Two differ- massage include recent (i.e., within the last three months) ent types of carotid sinus syndrome can be distinguished. In transient ischemic attacks, strokes, and myocardial infarc- the first type, called cardioinhibitory CSS ventricular asys- tions.6 Carotid bruits are also considered a contraindica- tole for more than 3 s reproducing the spontaneous symp- tion, except carotid Doppler excludes significant toms is seen. In the secondtype,referredtoas stenosis.6 Overall, in elderly patients with unexplained syn- vasodepressor CSS, the blood pressure drops more than cope—especially if triggered by certain head positions— 50 mmHg while ventricular asystole is either absent or monitored carotid sinus massage should be performed by Zo¨rner et al. 3 the specialist and only after contraindications have been References excluded. 1. Seifer C. Carotid sinus syndrome. Cardiol Clin 2013; 31: 111–121. Authors’ contributions 2. Lopes R, Goncalves A, Campos J, et al. The role of pacemaker BZ: acquisition and interpretation of the data, drafting the manu- in hypersensitive carotid sinus syndrome. Europace 2011; 13: script. JS: acquisition of data, revising the manuscript. ML: inter- 572–575. pretation of the data, revising the manuscript. AAT: interpretation 3. Sutton R. Carotid sinus syndrome: progress in understanding of the data, revising the manuscript. and management. Glob Cardiol Sci Pract 2014; 2014: 1–8. 4. Tsioufis CP, Kallikazaros IE, Toutouzas KP, et al. Exagger- Declaration of conflicting interests ated carotid sinus massage responses are related to severe cor- The author(s) declared the following potential conflicts of interest onary artery disease in patients being evaluated for chest pain. with respect to the research, authorship, and/or publication of this Clin Cardiol 2002; 25: 161–166. article: Dr Steffel has received consultant and/or speaker fees 5. Tea SH, Mansourati J, L’Heveder G, et al. New insights into from Amgen, Astra-Zeneca, Atricure, Bayer, Biosense Webster, the pathophysiology of carotid sinus syndrome. Circulation Biotronik, Boehringer-Ingelheim, Boston Scientific, Bristol- 1996; 93: 1411–1416. Myers Squibb, Cook Medical, Daiichi Sankyo, Medtronic, Novar- 6. Writing Committee M, Shen WK, Sheldon RS, et al. 2017 tis, Pfizer, Sanofi-Aventis, Sorin, St. Jude Medical/Abbott, and ACC/AHA/HRS guideline for the evaluation and management Zoll. Her reports ownership of CorXL. Dr Steffel has received of patients with syncope: a report of the American College of grant support through his institution from Bayer Healthcare, Bio- Cardiology/American Heart Association Task Force on Clin- sense Webster, Biotronik, Boston Scientific, Daiichi Sankyo, ical Practice Guidelines and the Heart Rhythm Society. Heart Medtronic, and St. Jude Medical/Abbott. Dr. Zo¨rner, Prof. Linne- bank and Dr. Tarnutzer do not report any conflict of interest. Rhythm 2017; 14: e155–e217. 7. Amin V and Pavri BB. Carotid sinus syndrome. Cardiol Rev 2015; 23: 130–134. Funding 8. Munro NC, McIntosh S, Lawson J, et al. Incidence of compli- The author(s) received no financial support for the research, cations after carotid sinus massage in older patients with syn- authorship, and/or publication of this article. cope. J Am Geriatr Soc 1994; 42: 1248–1251. 9. van Munster CE, van Ballegoij WJ, Schroeder-Tanka JM, et al. ORCID iD A severe stroke following carotid sinus massage. Ned Tijdschr Alexander A Tarnutzer http://orcid.org/0000-0002-6984-6958 Geneeskd 2017; 161: D826.