Treatment of Carotid Sinus Hypersensitivity: The authors reply

Abstract

We are grateful to Dr. Trout for his additional insights into the treatment of carotid sinus hypersensitivity. Carotid sinus denervation has indeed been recognized as a potential therapeutic approach for this syndrome since 1939, when 13 patients who underwent this procedure at the Mayo Clinic were described in a published report.1Craig WM Smith HL The surgical treatment of hypersensitive carotid sinus reflexes: a report of thirteen cases.Yale J Biol Med. 1939; 11: 415-422PubMed Google Scholar The outcome in that group was equivocal, and Dr. Trout is to be congratulated for his improved results.2Trout III, HH Brown LL Thompson JE Carotid sinus syndrome: treatment by carotid sinus denervation.Ann Surg. 1979; 189: 575-580Crossref PubMed Scopus (43) Google Scholar We would, however, be reluctant to accept the statement that carotid sinus denervation is the treatment of choice in patients with syncope and a hypersensitive carotid sinus reflex in the absence of a cardiac conduction defect. We have observed that the syncope of most patients with carotid sinus hypersensitivity, whether vasodepressor or cardioinhibitory, cannot be directly attributed to manipulation, compression, or distention of the carotid sinus despite the attention given to the relatively rare patient with “necktie” syncope. Rather, excessive bradycardia, hypotension, or symptoms caused by carotid sinus stimulation essentially serve as a provocative test of the cardioinhibitory-vasodepressor reflex arc. Patients in whom the defect may be located centrally or in the efferent limb of the reflex arc might best be managed by counteracting the effect at the target organ—for example, by cardiac pacing or pharmacologic therapy. The observation that ventricular pacing (as opposed to dual-chamber pacing, which we recommend) not uncommonly leads to pacemaker syndrome in these patients suggests that other afferent input, such as atrial mechanoreceptors, may also participate in the development of symptoms. Moreover, cardiac pacing is easily accomplished, widely accessible, highly reliable and safe, efficiently monitored, and effective in treating other concomitant bradyarrhythmias. On the basis of Dr. Trout's observations, we believe that carotid sinus denervation may be appropriately considered in patients with profound syncope related to mild carotid sinus massage (as exemplified by several of his patients2Trout III, HH Brown LL Thompson JE Carotid sinus syndrome: treatment by carotid sinus denervation.Ann Surg. 1979; 189: 575-580Crossref PubMed Scopus (43) Google Scholar). The possibility that this procedure may be particularly useful in vasodepressor carotid sinus syncope is attractive but cannot be evaluated on the basis of available data. Treatment of Carotid Sinus HypersensitivityMayo Clinic ProceedingsVol. 60Issue 2PreviewI applaud the initiation of “Cardiovascular Clinics” in the September 1984 issue of the Proceedings and thought that the article “Carotid Sinus Hypersensitivity and Syncope” (pages 637 to 640) was well written and informative. In the discussion, however, I was surprised that no mention was made of carotid sinus denervation as a treatment option. This simple operative procedure, which may be performed with use of local anesthesia, achieves excellent results with minimal associated morbidity.1 Moreover, long-term administration of anticholinergic drugs or insertion of a pacemaker is avoided. Full-Text PDF