Diagnosis of carotid sinus hypersensitivity in older adults: carotid sinus massage in the upright position is essential

A cross-sectional nationwide survey of guideline based syncope units in the Netherlands: the SU-19 score-a novel validation for best practices

AIMS

We aimed to identify all syncope units (SUs) in the Netherlands and assess the extent to which these SUs fulfil the essential requirements outlined by the consensus statements of the European Heart Rhythm Association and the European Society of Cardiology syncope guidelines. For this, we developed the SU-19 score, a novel guideline based validation tool for best practice.

METHODS AND RESULTS

All outpatient clinics of cardiology, neurology, and internal medicine in the Netherlands were screened for presence of any form of structured specialized syncope care. If present, these were included as SUs and requested to complete a questionnaire regarding syncope care. We assessed all SUs using the SU-19 score regarding structure (3 points), available tests (12 points), and initial evaluation (4 points). Twenty SUs were identified in the Netherlands, both academic (5/20) and non-academic hospitals (15/20), 17/20 reported multidisciplinary involvement during initial evaluation. In 19/20, neurology, cardiology, or both were responsible for the syncope management. Non-physicians were involved performing the head-up tilt test (44%) and initial evaluation (40%). The mean SU-19 score was 18.0 ± 1.1, 45% achieved the maximum score of 19 points. Variations were observed in protocols for active standing test, carotid sinus massage, and head-up tilt test.

CONCLUSION

There is a network of 20 SUs in the Netherlands. Forty-five per cent fully met the SU-19 score (mean 18.0 ± 1.1). Slight variety existed in protocols for autonomic function tests. Neurology and cardiology were mostly involved in syncope management. Non-physicians play an important role in syncope care.

Should We Ever Pace for Carotid Sinus Syndrome?

Carotid sinus syndrome has been associated with transient loss of consciousness for millennia, and while steeped in cardiovascular lore, there is little in the way of solid evidence to guide its main treatment modality, permanent cardiac pacing. This article reviews the history of the condition in the context of its contemporary understanding before examining three key concepts in the consideration of what constitutes a manageable disease: first, is there a pathophysiologic rationale for the disease (in this case carotid sinus syndrome)? Second, is there a good diagnostic test that will identify it reliably? And finally, is there a convincingly evidence-based treatment for the disease? Relevant literature is reviewed, and recommendations made in how we view pacing in the context of this intriguingly opaque condition.

Severe bradycardia caused by the deviation of the laryngeal mask airway Supreme: A case report

RATIONALE

Classic laryngeal mask airway (LMA) has long been used for airway management. The LMA Supreme is a modified single-use version of the LMA Proseal, but it still remains some deficits such as the instable positioning that lead to easily sliding and the mask bowl full of air might lead to the reduced blood flow of the internal carotid artery. The carotid sinus is a baroreceptor that responds to the stretching of the arterial wall. Manual pressure of the carotid artery at the upper margin of the sternocleidomastoid muscle provoked bradycardia and hypotension.

PATIENT CONCERNS

A previously fit and well 42-year-old woman presented with breast fibroma on the left side. No other disease history could be recorded. Her family history was negative for neuromuscular and autoimmune disease.

DIAGNOSES

The patient suffered from a severe bradycardia and hypotension when the LMA showed a shift. We presented with a hypothetical that the dislocated LMA may cause carotid sinus syndrome (CSS).

INTERVENTIONS

The patient's heart rate (HR) gradually rosed up as soon as the LMA adjusted back to the normal position.

OUTCOMES

The patient was comfortable in the post anesthesia care unit (PACU) and had no adverse sequelae.

LESSONS

The position of LMA Supreme should be confirmed throughout the surgery especially for the ones who has changed the position and the head was covered by surgical drapes.

Massage du sinus carotidien

Le massage du sinus carotidien (MSC) est un geste simple, utilisé en médecine d’urgence à visées diagnostique et/ou thérapeutique. Les indications principales au MSC sont l’évaluation des syncopes chez les patients de plus de 40 ans et le traitement de première ligne des tachycardies paroxystiques supraventriculaires bien tolérées hémodynamiquement. Les contre-indications incluent un antécédent d’accident vasculaire cérébral ou d’accident ischémique transitoire dans les trois mois qui précèdent ainsi que la présence d’une sténose carotidienne significative ou d’un souffle carotidien. Dans le bilan de la syncope, le MSC permet de diagnostiquer une hypersensibilité du sinus carotidien. Pour les tachycardies supraventriculaires, il permet de préciser le type de tachycardie et, dans certains cas, d’obtenir une restauration d’un rythme sinusal. Les rares complications sont liées au risque de provoquer une embolie cérébrale.

Carotid Sinus Massage in Syncope Evaluation: A Nonspecific and Dubious Diagnostic Method

BACKGROUND

Carotid sinus hypersensitivity (CSH) is a frequent finding in the evaluation of syncope. However, its significance in the clinical setting is still dubious. A new criterion was proposed by Solari et al. with a symptomatic systolic blood pressure (SBP) cut-off value of ≤ 85 mmHg to refine the vasodepressor (VD) response diagnosis.

OBJECTIVE

To determine and compare the response to carotid sinus massage (CSM) in patients with and without syncope according to standard and proposed criteria.

METHODS

CSM was performed in 99 patients with and 66 patients without syncope. CSH was defined as cardioinhibitory (CI) for asystole ≥ 3 seconds, or as VD for SBP decrease ≥ 50 mmHg.

RESULTS

No differences in the hemodynamic responses were observed during CSM between the groups, with 24.2% and 25.8% CI, and 8.1% and 13.6% VD in the symptomatic and asymptomatic groups, respectively (p = 0.466). A p value < 0.050 was considered statistically significant. During the maneuvers, 45 (45.45%) and 34 (51.5%) patients in the symptomatic and asymptomatic groups achieved SBP below ≤ 85 mmHg. Symptoms were reported especially in those patients in whom CSM caused a SBP decrease to below 90 mmHg and/or asystole > 2.5 seconds, regardless of the pattern of response or the presence of previous syncope.

CONCLUSION

The response to CSM in patients with and without syncope was similar; therefore, CSH may be an unspecific condition. Clinical correlation and other methods of evaluation, such as long-lasting ECG monitoring, may be necessary to confirm CSH as the cause of syncope.

The accuracy of anatomical landmarks for locating the carotid sinus

BACKGROUND

carotid sinus massage (CSM) is a valuable clinical test for carotid sinus syndrome (CSS) and relies on accurately locating the carotid sinus (CS).

OBJECTIVE

in this study, we sought to examine the accuracy of using anatomical landmarks for locating the CS.

METHODS

consecutive patients (n = 20) were recruited prospectively. Two clinicians, trained in CSM, were asked to locate the CS using anatomical landmarks. A point on the skin overlying the CS was then marked by a vascular technician using ultrasound. Accuracy of techniques was compared using intra-class correlation coefficients and Bland-Altman statistics.

RESULTS

anatomical landmarks underestimated the CS location by 1.5 ± 1.3 cm. Error extremes ranged from 4 cm below to 2 cm above CS using anatomical landmarks. A moderate correlation between ultrasound and anatomical landmarks was found, r = 0.371 (P = 0.031).

CONCLUSION

this is the first study to characterise the accuracy of standard anatomical landmarks used in CSM. Results suggest that the point of maximal pulsation has the lowest associated error. Future work should examine CSM yield across this and a range of other methodological factors.

Carotid sinus syndrome: Progress in understanding and management

Carotid sinus syndrome (CSS) is a disease of the autonomic nervous system presenting with syncope, especially in older males who often have cardiovascular disease. The aetiology is unknown and epidemiological data is limited. Forty new patients/million population have been estimated to require pacing for CSS and these patients represent ∼9% of those presenting syncope to a specialist facility. CSS is defined as a response to carotid sinus massage (CSM) that includes reproduction of spontaneous symptoms. Cardioinhibitory CSS shows 3s asystole on CSM and vasodepressor CSS shows >50 mmHg fall in blood pressure (BP), there are mixed forms. The methodology of CSM requires correct massage in the supine and upright with continuous ECG and BP. Assessment of the vasodepressor component implies the ‘method of symptoms’ using atropine to prevent asystole. Carotid sinus hypersensitivity (CSH) is a related condition where CSM is positive in an asymptomatic patient. CSH cannot be assumed to respond to pacing. CSS patients present syncope with little or no warning. If no cause is revealed by the initial evaluation, CSM should be considered in all patients >40 years. CSM carries a small risk of thromboembolism. Therapy for cardioinhibitory CSS is dual chamber pacing, which is most effective in patients with a negative tilt test. Syncope recurrence is ∼20% in 5 years in paced patients. Therapy for the vasodepressor component of CSS, as pure vasodepression or mixed, where tilt testing will likely be positive, is often unrewarding: alternative therapeutic measures may be needed including discontinuation/reduction of hypotensive drugs.

Aerobic training in older adults with type 2 diabetes and vasodepressive carotid sinus hypersensitivity

BACKGROUND AND AIMS

Vasodepressive carotid sinus hypersensitivity (V-CSH) is a common but incurable etiology for fainting in older adults with diabetes (OADM), and is diagnosed by carotid sinus massage (CSM). Aerobic exercise has been shown to be an effective therapy for other neuroautonomic etiologies of syncope (such as orthostatic hypotension), but the effectiveness of aerobic training in V-CSH remains unknown. We examined whether aerobic training could attenuate the vasodepressive response to CSM in OADM (older adults with type 2 diabetes) subjects complicated by V-CSH.

METHODS

Forty OADM subjects (mean age 72.2 ± 0.7) complicated by V-CSH were recruited. Subjects were randomized to each of two groups: an aerobic group (AT, n = 20, 3 months vigorous aerobic exercise), and a nonaerobic (NA, n = 20, no aerobic exercise) group. Exercise sessions were supervised by a certified exercise trainer three times per week. The vasodepressive response [defined as the decrease in systolic blood pressure (SBP) during CSM] was measured before and after the training intervention using a Finometer.

RESULTS

The intervention had no impact on the number of subjects that met the criteria for V-CSM in either the AT or NA groups, regardless of the criteria used (-10, -20, -30, -40 and -50 mmHg). There was no training effect on the vasodepressive response in either the AT or NA group (P = 0.214, 2-way analysis of variance, -30 mmHg definition for V-CSH).

CONCLUSIONS

Aerobic training has no effect on the SBP response to CSM in OADM subjects with V-CSH. Unlike in other neuroautonomic etiologies for fainting, aerobic exercise is not effective as a treatment for V-CSH, at least in the OADM population.

Cardiovascular effects of abduction shoulder sling in elderly patients; is it really safe?

OBJECTIVE

The purpose of the prospective study is to investigate the cardiovascular effects of abduction shoulder sling (ASS) in elderly patients who underwent rotator cuff surgery.

METHODS

The study included 49 consecutive patients older than 50 years (mean 59.3 ± 8.2 years) who underwent arthroscopic rotator cuff repair surgery and used ASS in postoperative period. All cases underwent Holter electrocardiographic monitoring before (24 h) and after (48 h) the operation. The Holter findings were read by an experienced cardiologist and a pause of longer than 3 s and heart rate of <40 bpm was evaluated as significant bradycardia.

RESULTS

One patient (61-year-old male) described feeling faint (presyncope) which was confirmed with the Holter finding of a pause more than 3 s which occurred in the day time. Two other patients (52-year-old male, and 62-year-old female) reported severe dizziness (hypotensive attack) which required admission to a general practitioner. However, Holter findings were normal in these patients. These three cases were referred to cardiology department for evaluation of carotid hypersensitivity syndrome (CSH). CSH was confirmed with tests made with provocative maneuvers in a sitting position. CSH was defined as at least 3 s of asystole (cardio-inhibitor type) during carotid massage or systolic blood pressure falling below 50 mmHg (vaso-depressor type). All three patients were obese patients and BMI was higher than 30.

CONCLUSIONS

ASS may trigger CSH in short necked and obese patients by exerting mechanical stimulation to the carotid sinus. These patients should be informed about symptoms and signs of CSH and educated on the proper use of ASS and correct positioning of shoulder strap. CSH should be kept in mind in patients who present with dizziness, presyncope and palpitation during the postoperative period.

At the heart of the arterial baroreflex: a physiological basis for a new classification of carotid sinus hypersensitivity

The aim of this review is to provide an update of the current knowledge of the physiological mechanisms underlying reflex syncope. Carotid sinus syncope will be used as the classical example of an autonomic reflex with relatively well-established afferent, central and efferent pathways. These pathways, as well as the pathophysiology of carotid sinus hypersensitivity (CSH) and the haemodynamic effects of cardiac standstill and vasodilatation will be discussed. We will demonstrate that continuous recordings of arterial pressure provide a better understanding of the cardiovascular mechanisms mediating arterial hypotension and cerebral hypoperfusion in patients with reflex syncope. Finally we will demonstrate that the current criteria to diagnose CSH are too lenient and that the conventional classification of carotid sinus syncope as cardioinhibitory, mixed and vasodepressor subtypes should be revised because isolated cardioinhibitory CSH (asystole without a fall in arterial pressure) does not occur. Instead, we suggest that all patients with CSH should be thought of as being 'mixed', between cardioinhibition and vasodepression. The proposed stricter set of criteria for CSH should be evaluated in future studies.

Carotid sinus syndrome is common in very elderly patients undergoing tilt table testing and carotid sinus massage because of syncope or unexplained falls

BACKGROUND AND AIMS

Although the incidence of falls and syncope increase with age, the underlying mechanisms are not fully understood, particularly in very old patients. We report diagnostic outcomes of tilt table and carotid sinus massage (TT/CSM) testing in a population of older old subjects (82% over 80 years of age) referred for TT/CSM from a falls clinic for assessment of syncope or unexplained falls.

METHODS

Prospective observational study between January 1, 2001 and January 1, 2005 involving 290 consecutive subjects undergoing TT/CSM testing according to European Society of Cardiology guidelines for the diagnosis and management of syncope.

RESULTS

Combination of TT/CSM provided a positive result in 62% of subjects, and was significantly more likely to be positive in subjects over the age of 80 (68% vs 50%, p=0.001). Carotid sinus syndrome (CSS) was the most common diagnosis, and was significantly more common in subjects over 80 (48% vs 34%, p=0.022) particularly due to a higher incidence of mixed CSS (16% vs 7%, p=0.023). There was no significant difference in the diagnosis of subjects referred due to falls and those reporting syncope (p=0.93). No cardiovascular or neurological adverse events occurred.

CONCLUSIONS

In our cohort of very elderly patients, the diagnostic accuracy of tilt testing and carotid sinus massage was high and adverse incidents absent when testing was indicated by a geriatrician experienced in the assessment of falls and syncope. We advocate the use of TT/CSM testing as part of a comprehensive falls/syncope assessment for the diagnostic evaluation of older patients presenting with unexplained falls and/or syncope in whom structured assessment has not identified a cause for their symptoms.

Dissection of carotid sinus hypersensitivity: the timing of vagal and vasodepressor effects and the effect of body position

We assessed the timing of vagal and sympathetic factors that mediate hypotension during CSM (carotid sinus massage) in patients with carotid sinus hypersensitivity. We hypothesized that a fall in cardiac output would precede vasodepression, and that vasodepression would be exaggerated by head-up tilt. We performed pulse contour analyses on blood pressure recordings during CSM in syncope patients during supine rest and head-up tilt. In a subset we simultaneously recorded muscle sympathetic nerve activity supine. During supine rest, systolic blood pressure decreased from 150±7 to 107±7 mmHg (P<0.001) and heart rate from 64±2 to 39±3 beats/min (P<0.01). Cardiac output decreased with heart rate to nadir (66±6% of baseline), 3.1±0.4 s after onset of bradycardia. In contrast, total peripheral resistance reached nadir (77±3% of baseline) after 11±1 s. During head-up-tilt, systolic blood pressure fell from 149±10 to 90±11 mmHg and heart rate decreased from 73±4 to 60±7 beats/min. Compared with supine rest, cardiac output nadir was lower (60±8 compared with 83±4%, P<0.05), whereas total peripheral resistance nadir was similar (81±6 compared with 80±3%). The time to nadir from the onset of bradycardia did not differ from supine rest. At the onset of bradycardia there was an immediate withdrawal of muscle-sympathetic nerve activity while total peripheral resistance decay occurred much later (6–8 s). The haemodynamic changes following CSM have a distinct temporal pattern that is characterized by an initial fall in cardiac output (driven by heart rate), followed by a later fall in total peripheral resistance, even though sympathetic withdrawal is immediate. This pattern is independent of body position.

Arterial stiffness and the response to carotid sinus massage in older adults

BACKGROUND AND AIMS

Carotid sinus hypersensitivity (CSH) is a common cause of fainting and falls in the older adult population and is diagnosed by carotid sinus massage (CSM). Previous work has suggested that age-related stiffening of blood vessels reduces afferent input from the carotid sinus leading to central upregulation of the overall arterial baroreflex response. We examined the differences in arterial stiffness and baroreflex function in older adults at high cardiovascular risk (advanced age, Type 2 diabetes, hypertension and hyperlipidemia) with and without CSH.

METHODS

Forty-three older adults (mean age 71.4+/-0.7) with Type 2 diabetes, hyperlipidemia and hypertension were recruited. After resting supine for 45 minutes prior to the start of data collection, each subject had arterial stiffness measured by pulse wave velocity (PWV, Complior SD), followed by spontaneous baroreflex measures (Baroreflex sensitivity, BRS) and CSM.

RESULTS

Of the 43 subjects tested, 10 subjects met the criteria for CSH (8 pure vasodepressor and 2 mixed CSH). CSH subjects had higher measures of arterial stiffness when compared to normal subjects for both radial PWV (11.5+/-0.6 vs 9.6+/-0.4 m/s, p=0.043) and femoral PWV (13.4+/-0.9 vs 11.0+/-0.5 m/s, p=0.036). The CSH group demonstrated significantly lower BRS as compared to the normal group (BRS, 6.73+/-0.58 vs 10.41+/-0.85 ms/mmHg, p=0.038). These results were unchanged when the analysis was repeated with only the VD subjects.

CONCLUSIONS

Older adults with CSH have higher arterial stiffness and reduced arterial baroreflex sensitivity. There was no evidence to support upregulation of the arterial baroreflex in patients with CSH.

Results of carotid sinus massage in a tertiary referral unit--is carotid sinus syndrome still relevant?

BACKGROUND

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.

OBJECTIVE

we conducted a retrospective observational study to investigate the haemodynamic and symptom responses of a large cohort of patients undergoing carotid sinus massage (CSM).

METHODS

the electronically stored haemodynamic data of 302 consecutive patients, aged 71 +/- 11 years, investigated with CSM for unexplained falls and syncope was analysed. Bilateral sequential CSM was performed in the supine and upright positions with continuous electrocardiogram (ECG) and non-invasive beat-to-beat blood pressure monitoring (Taskforce, CN Systems, Austria). CSH (CSH) was defined by maximal R-R interval > or =3 s (cardioinhibitory) and/or a systolic blood pressure drop of > or =50 mmHg (vasodepressor).

RESULTS

a total of 74/302 (25%) subjects had CSH, 37 (50%) of which were cardioinhibitory (CI) and 37 (50%) were vasodepressor (VD) subtypes. Subjects with positive CSM were significantly older (75.2 vs 70.2 years, P < 0.001), and more likely to be male (32% vs 19%, P < 0.01). CSH was diagnosed with right-sided CSM alone in 45 (61%) subjects and erect CSM only in 36 (49%) subjects. Symptom reproduction was more likely with the CI than the VD subtypes (82% vs 28%; P < 0.001).

CONCLUSION

CSH was diagnosed in 25% of patients investigated with CSM at our specialist unit, lower than the prevalence of 39% reported for community-dwelling older individuals. This discrepancy may be explained by selection bias and demographic differences, but raises the possibility of CSH being an age-related epiphenomenon rather than a causal mechanism for syncope, drop attacks and unexplained falls. Our observations have important implications for clinical practice and the development of future research strategies.

Cardiovascular assessment of falls in older people

Falls in older people can be caused by underlying cardiovascular disorders, either because of balance instability in persons with background gait and balance disorders, or because of amnesia for loss of consciousness during unwitnessed syncope. Pertinent investigations include a detailed history, 12-lead electrocardiography, lying and standing blood pressure, carotid sinus massage (CSM), head-up tilt, cardiac electrophysiological tests, and ambulatory blood pressure and heart rate monitoring, which includes external and internal cardiac monitoring. The presence of structural heart disease predicts an underlying cardiac cause. Conversely, the absence of either indicates that neurally mediated etiology is likely. CSM and tilt-table testing should be considered in patients with unexplained and recurrent falls. Holter monitoring over 24 hours has a low diagnostic yield. Early use of an implantable loop recorder may be more cost-effective. A dedicated investigation unit increases the likelihood of achieving positive diagnoses and significantly reduces hospital stay and health expenditure.

Neurally mediated syncope and unexplained or nonaccidental falls in the elderly

Falls and syncope are among the leading causes for which older patients seek hospital admissions. The prevalence of unexplained or nonaccidental falls is high in this group. The clinical spectrum of falls and syncope has been shown to overlap significantly in the elderly. Carotid sinus syndrome and vasovagal syncope, the two common examples of neurally mediated syncope (NMS), have been increasingly recognised as important attributable causes for unexplained falls and syncope. However, in clinical practice NMS is not widely investigated as a cause of fall and is likely to be underdiagnosed.

Role of autonomic evaluation in the diagnosis and management of syncope

There are many causes of syncope that include neurological (autonomic and non-autonomic), cardiac and psychiatric causes, amongst others. Disorders of the autonomic nervous system, either intermittent or fixed, are increasingly recognised as contributing to a large proportion of syncope. However, the majority of guidelines focus on cardiological and neurological evaluation in these disorders. In this overview we focus specifically on the role of autonomic evaluation. This has dual purposes; to aid the diagnosis and cause of syncope, and furthermore to provide information to understand the pathophysiological basis of syncope and thus improve management of such disorders.

The management of patients with carotid sinus syndrome: is pacing the answer?

Carotid sinus syndrome (CSS) is an under recognized cause of recurrent unexplained syncope and potentially of recurrent falls in the elderly. The mechanisms that lead to syncope in patients with CSS remain debated. However, evidence for both peripheral and central alterations have been recently reported. The diagnosis of CSS is challenging and a high clinical suspicion is usually needed to make the diagnosis. Clinical presentation may be typical and characterized by a clear association between accidental manipulation of the carotid sinus and the presentation of syncope. On the other hand, recurrent unexplained syncope and unexplained falls may be the clinical presentation of patients with CSS without a specific trigger. Carotid sinus hypersensitivity documented by carotid sinus massage (CSM) may be the only finding indicating the possibility of CSS as the cause of syncope. In older patients with recurrent unexplained syncope and a negative diagnostic work-up, carotid sinus massage both in the supine and upright positions is recommended. CSS may present primarily as a cardioinhibitory response or a true vasodepressor response. Therapy should address any underlying pathology if present, and be directed to either prevent cardioinhibition, vasodepression or both alterations. A variety of medical therapies have been used with unclear effects. No appropriately designed controlled clinical trials have been performed comparing pacing with medical therapy. Nonetheless, available information indicates that pacing may have a strong beneficial effect and prevents recurrence of syncope in patients with CSS. The present paper critically reviews the latest insights in the pathophysiology, diagnosis and management of CSS.

[Value and limitations of carotid sinus massage in healthy elderly individuals. Evaluation of diagnostic criteria for hypersensitive carotid sinus syndrome]

OBJECTIVE

To study the value and limitations of carotid sinus massage in healthy individuals older then 50 years of age, in order to assess the validity of the widely used criteria for the diagnosis of hypersensitive carotid sinus syndrome.

METHODS

Right and left carotid sinus massage was performed in 120 healthy individuals older then 50 years of age (74 males and 46 females aged 59 +/- 7 years) who had no prior history of syncope, pre-syncope, or abnormal bradyarrhythmia, during EKG monitoring.

RESULTS

Hypersensitivity of the carotid sinus (HSCS) defined as a pause > 3 s, was found in 28 individuals (23.3%). The pause was induced by right carotid sinus massage in 20 cases and by left carotid sinus massage in 8 cases. Patients demonstrating HSCS were older compared to those who did not develop a pause. One or multiple blocked P wave was seen in 16 cases when carotid sinus massage was performed on the left side compared to 8 with right carotid sinus massage.

CONCLUSION

In healthy individuals older than 50 years of age, it is not rare to induce a significant pause following carotid sinus massage. This limits the validity of the widely used criteria for the diagnosis of hypersensitive carotid sinus syndrome. Additional criteria are proposed to make this diagnosis in front of a brief loss of consciousness.

[Syncope in the elderly: diagnostic utility of carotid sinus massage in the head-up tilt test]

A 71-year-old man presented with a 6-month history of fainting. Consciousness was quickly regained without clouding or confusion. Ancillary investigations were inconclusive and he was treated with carbamazepine. The fainting spells did not cease and he was referred for a tilt-table test exam. In the head-up position (table tilted at 60 degrees), massage of the carotid sinus was immediately followed by asystole, unconsciousness, and a sharp drop in arterial pressure for 5 seconds. The same procedure in the lying position did not elicit clinical symptoms or haemodynamic imbalance. A diagnosis of carotid sinus hypersensitivity with a cardio-inhibitory response pattern was made. Carbamazepine was withdrawn and a double-chamber pacemaker was implanted in his right ventricle. He remained symptom-free for the ensuing 18 months. This case supports the diagnostic utility of carotid sinus massage during the head-up tilt test in patients with unexplained non-convulsive loss of consciousness.

Carotid sinus syndrome

This article reviews the recent literature about carotid sinus syndrome. It looks principally at the various ways in which it may present, the limited knowledge of its pathophysiology, and the role of carotid sinus massage in the investigation of carotid sinus syndrome.

Outcomes of permanent pacemaker implantation for carotid sinus hypersensitivity in a district general hospital with a Falls Fits Faints and Funny Turns Clinic

Permanent pacemaker implantation is considered for carotid sinus hypersensitivity with asystolic pause of > 3 seconds during carotid sinus massage, with or without associated systolic blood pressure drop of > 50 mmHg.

AIMS

To assess the outcome of treatment with dual chamber permanent pacemaker implantation for carotid sinus hypersensitivity in a district general hospital and to compare our practice with available national data.

METHODS

Patients presenting with syncope, dizziness or unexplained falls were initially assessed as outpatient and investigations, commonly cardiovascular were performed including tilt table test with carotid sinus massage to look for carotid sinus hypersensitivity, vasovagal syncope and postural hypotension. A retrospective analysis was performed on patients who had pacemaker implantations for carotid sinus hypersensitivity.

RESULTS

Fifty pacemaker implantations were performed, 14 (28%) were for carotid sinus hypersensitivity. Mean follow-up period was 10 months. Age range was 56-88 (mean = 71.9) years. In the eighteen months prior to pacemaker implantation, 71.4% of patients had syncope, 64% dizziness and 50% had unexplained falls. Following pacemaker implantations, only 2 (14.3%) had symptoms. Scottish national figures show 13.6% of all new pacemaker implants were for carotid sinus hypersensitivity, and in district general hospitals this was 16%.

CONCLUSIONS

Health benefits for patients presenting with syncope dizziness and falls can be achieved by cardiovascular investigations including tilt table testing. We have shown carotid sinus hypersensitivity is successfully treated with pacemaker implantation in a district general hospital setting and this type of clinic has an impact on the rate and type of new pacemaker implantation.

Neurocardiovascular instability in cognitive impairment and dementia

Neurocardiovascular instability (NCVI, neurally mediated disorders causing hypotension with or without bradycardia) represents abnormal neural control of the cardiovascular system and presents as dizziness, syncope, or falls. The mechanisms underpinning NCVI are incompletely understood. The three most common disorders are carotid sinus syndrome (CSS), orthostatic hypotension (OH), and vasovagal syndrome (VVS): CSS, cardioinhibition > 3 s and/or vasodepressor response > or = 50 mmHg drop in systolic pressure during carotid sinus stimulation; OH: fall in systolic blood pressure > 20 mmHg during standing; VVS: cardioinhibition > 3 s and/or vasodepressor response > 50 mmHg during prolonged head-up tilting. In fallers with cognitive impairment or dementia, the prevalence of NCVI is 70%. Multifactorial interventions, including treatment of NCVI, significantly reduce falls and syncope. The predominant components of NCVI in fallers with cognitive impairment and dementia are CSS and OH. In Lewy body and Alzheimer's dementia, the prevalence of NCVI is up to 60%, again predominantly CSS and OH. The prevalence of cardioinhibitory carotid sinus hypersensitivity is particularly high in Lewy body dementia-41% compared with 12% in Alzheimer's disease and 3% in case controls. In addition, patients with Lewy body dementia have greater heart rate slowing (>2 s) and falls in systolic blood pressure (>20 mmHg) than those with Alzheimer's disease or controls during carotid sinus stimulation. The extent of deep white matter hyperintensities on MRI correlates with systolic fall during carotid sinus stimulation (R = 0.58; p < 0.005), suggesting a possible causal association between bradyarrhythmia-induced hypotension and microvascular pathology. NCVI is common in patients with dementia and may be a reversible cause of falls and syncope. Repeated hypotensive episodes may exaggerate cognitive decline in these patients.

Evaluating elderly patients with syncope

Age-related physiologic changes together with high prevalence of chronic illness and the use of multiple medications predispose older adults to syncope. The causes of many of these patients' syncope are unexplained and most remained symptomatic. A thoughtful diagnostic strategy is essential to pinpoint the cause in each patient. The initial assessment includes a comprehensive medical history, preferably with an eye witness account, and a thorough physical examination. The decision for further diagnostic tests often depends on whether there is evidence of underlying structural heart disease. In the absence of heart disease, tilt table testing and the related autonomic function testing are usually most productive. Various cardiac studies will be more appropriate for those with suspected structural heart disease. A cause of syncope can only be concluded if there is a sufficiently strong correlation between syncopal symptoms and the detected abnormalities on investigations. A strategic evaluation of syncope of the elderly subjects should allow a correct diagnosis and appropriate management.

Neurally mediated syncope

The prevalence and incidence of syncope increases with advancing years due to age related physiological changes in the neurocardiovascular, endocrine and renal systems. Cardiovascular syncope can present as falls because of amnesia for loss of consciousness or postural instability due to hypotension. Drop attacks or non accidental falls should thus be investigated for causes of syncope. The most common causes of neurally mediated syncope in older adults are carotid sinus syndrome, orthostatic hypotension and vasovagal syncope.

Carotid sinus syndrome: a modifiable risk factor for nonaccidental falls in older adults (SAFE PACE)

OBJECTIVES

The aim of the study was to determine whether cardiac pacing reduces falls in older adults with cardioinhibitory carotid sinus hypersensitivity (CSH).

BACKGROUND

Cardioinhibitory carotid sinus syndrome causes syncope, and symptoms respond to cardiac pacing. There is circumstantial evidence for an association between falls and the syndrome.

METHODS

A randomized controlled trial was done of consecutive older patients (>50 years) attending an accident and emergency facility because of a non-accidental fall. Patients were randomized to dual-chamber pacemaker implant (paced patients) or standard treatment (controls). The primary outcome was the number of falls during one year of follow-up.

RESULTS

One hundred seventy-five eligible patients (mean age 73 +/- 10 years; 60% women) were randomized to the trial: pacemaker 87; controls 88. Falls (without loss of consciousness) were reduced by two-thirds: controls reported 669 falls (mean 9.3; range 0 to 89), and paced patients 216 falls (mean 4.1; range 0 to 29). Thus, paced patients were significantly less likely to fall (odds ratio 0.42; 95% confidence interval: 0.23, 0.75) than were controls. Syncopal events were also reduced during the follow-up period, but there were much fewer syncopal events than falls-28 episodes in paced patients and 47 in controls. Injurious events were reduced by 70% (202 in controls compared to 61 in paced patients).

CONCLUSIONS

There is a strong association between non-accidental falls and cardioinhibitory CSH. These patients would not usually be referred for cardiovascular assessment. Carotid sinus hypersensitivity should be considered in all older adults who have non-accidental falls.