The usefulness of carotid sinus massage in different patient groups

AIM: to determine the positive yield of carotid sinus massage in different patient groups: unexplained syncope, falls, dizziness and controls. DESIGN: observational study. SETTING: teaching hospital. METHODS: we studied consecutive patients over the age of 60 years referred to the 'falls clinic' with a history of unexplained syncope, unexplained falls and unexplained dizziness. We also studied asymptomatic control subjects recruited from a general practice register aged 60 years and over. All patients and control subjects underwent a full clinical assessment (comprehensive history and detailed clinical examination including supine and erect blood pressure measurements) and 12-lead electrocardiography. We performed carotid sinus massage in the supine position for 5 seconds separately on both sides followed by repeating the procedure in the upright positions using a motorised tilt table. Heart rate and blood pressure were recorded using a cardiac monitor and digital plethysmography respectively. The test was considered positive if carotid sinus massage produced asystole with more than a 3 second pause (cardioinhibitory type of carotid sinus syndrome), or a fall in systolic blood pressure of more than 50 mmHg in the absence of significant cardioinhibition (vasodepressor type of carotid sinus syndrome) or where there was evidence of both vasodepressor and cardio-inhibition as above (mixed type). RESULTS: we studied 44 asymptomatic control subjects and 221 symptomatic patients (130 with unexplained syncope, 41 with unexplained falls and 50 with unexplained dizziness). In the overall symptomatic patient group, the positive yield (any type of carotid sinus syndrome) was 17.6% (95% CI = 12.7-22.5). The positive yield in men (26.3% (95% CI = 16.4-36.2)) was twice that in women (13.1% (95% CI = 7.6-18.6)) (P = 0.014). Overall any type of carotid sinus syndrome was present in 22.3% (n = 29) of the syncope group, 17.1% (n = 7) in the unexplained fallers group and 6% (n = 3) in the dizziness group. We also found that no women with unexplained dizziness had a positive carotid sinus massage test. None of the controls demonstrated a positive response. None of the subjects suffered any complications during or after the test. CONCLUSION: the positive yield of carotid sinus massage in symptomatic patients was 17.6% with the yield in men being twice that in women. None of the asymptomatic control subjects demonstrated a positive response. The yields in unexplained syncope and unexplained falls patients were around 4-fold and 3-fold higher respectively than in unexplained dizziness patients. The positive yield in women with unexplained dizziness (without a definite history of syncope and falls) is zero. Hence, carotid sinus massage in older adults should particularly be targeted at patients with unexplained syncope and unexplained falls.     

Carotid sinus hypersensitivity is common in older patients presenting to an accident and emergency department with unexplained falls

OBJECTIVE: To determine the prevalence of carotid sinus hypersensitivity and orthostatic hypotension in older patients with non-accidental falls attending an accident and emergency department. DESIGN: A prospective case-control non-randomized study. Data were collected from semi-structured interviews, physical examination and neurocardiovascular investigations. SETTING: We recruited cases and controls from an inner-city accident and emergency department. PARTICIPANTS: 26 consecutive patients presenting to accident and emergency with non-accidental falls and 54 controls matched for age, sex and cognitive function presenting to the same department either because of an accidental fall or a reason other than falling. MAIN VARIABLES MEASURED: Detailed history and clinical evaluation, including postural phasic blood pressure measurements, heart rate and blood pressure responses to supine and upright carotid sinus stimulation. RESULTS: Orthostatic blood pressure responses did not differ between groups. The heart rate and blood pressure responses to carotid sinus massage were abnormal in patients with non-accidental falls compared with controls (P=0.002). Asystolic responses were present in 12 (46%) of 26 cases and seven (13%) of 54 controls. Loss of consciousness occurred during carotid sinus massage in seven (27%) of the cases, all of whom had asystole, and in none of the controls. CONCLUSIONS: Almost half of the cognitively normal older patients attending accident and emergency with non-accidental falls have carotid sinus hypersensitivity, emphasizing that a post-fall intervention strategy should include carotid sinus studies.     

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.     

Predictors of falls in elderly people during rehabilitation after hip fracture--who is at risk of a second one?

BACKGROUND: A fall in old age is known as a common consequence of frailty and decline as well as a risk factor for further falls. Studies identifying hip fracture patients who are at risk of a further fall are lacking. Therefore it was of interest to evaluate the risk factors for falling in a high-risk population, i.e., patients during rehabilitation after recent proximal femur fracture. METHODS: 935 consecutive patients who had surgical intervention after acute fracture of the proximal femur underwent a multidimensional assessment within the first two days after admission to the rehabilitation ward. Falls during the stay on the rehabilitation ward were registered. The baseline data were compared between fallers and non-fallers. FINDINGS: 11.8% of the patients fell during rehabilitation. Risk factors associated with a fall were increasing age, male gender, type of surgery, the use of a rollator and nocturnal urinary incontinence. The risk of falling increased in the middle of the second week of rehabilitation, when frailer patients gained mobility and ability to walk by themselves, while they were not yet safe enough. INTERPRETATION: It was possible to compose a risk profile for future falls. Those identified as 'at risk of a further fall' should be selectively offered protective devices and special training programs in order to prevent future fractures. As for the surgical intervention, the type of surgery in relation to age and long-term outcome is of particular interest since the use of the more expensive total hip arthroplasty procedure may be more cost effective in the long term.     

Characteristics of early fallers on elderly patient rehabilitation wards

BACKGROUND: falls are one of the most frequent complications on rehabilitation wards for elderly patients. OBJECTIVE: to study the characteristics of early and late fallers. DESIGN: prospective observational study with blinded end-point evaluation. SETTING: a non-acute geriatric hospital. SUBJECTS: 1025 consecutive patients admitted for rehabilitation following treatment for an acute illness. MAIN OUTCOME MEASURES: early/late fallers and time to first fall from admission. RESULTS: we identified 824 non-fallers and 201 fallers. Seventy seven (38.3%) fell during the first week. The incidence decreased progressively in subsequent weeks. Early fallers were more likely to have a past history of falls (P=0.0009), an unsafe gait (P=0.001), confusion (P<0.0001) and be admitted from medical wards (P=0.03). Patients admitted from orthopaedic wards having sustained a lower limb fracture were significantly less likely to have an early fall compared to all other patients (P=0.027). When compared to later fallers, early fallers were more likely to have a past history of falls (P=0.045). They were less likely to be admitted from an orthopaedic ward (P=0.01) or to have sustained a fracture of the lower limbs (P=0.002). Logistic regression analysis showed that a past history of falls, confusion and an unsafe gait were independent risk factors predisposing to early falls. The Kaplan-Meier survival analysis showed a significantly higher cumulative risk of falling associated with these characteristics. CONCLUSION: the initial week of patients' rehabilitation is associated with the greatest risk of falling. Early fallers can be predicted by easily identifiable characteristics. This highlights the need for early fall risk assessment.     

Diagnostic utility of mechanical, pharmacological and orthostatic stimulation of the carotid sinus in patients with unexplained syncope.

OBJECTIVES: The purpose of the present study was to systematically evaluate the diagnostic utility of mechanical, pharmacological and orthostatic stimulation of the carotid sinus in a consecutive series of patients with recurrent unexplained syncope. BACKGROUND: Carotid sinus hypersensitivity (CSH) is an infrequently recognized cause of recurrent unexplained syncope usually diagnosed by carotid sinus massage (CSM) in the supine position. The diagnostic utility of systematic assessment of mechanical, pharmacological and orthostatic stimulation of the carotid sinus has not been clearly established. METHODS: Eighty consecutive patients (63 +/- 12 years) with a history of recurrent unexplained syncope (mean episodes: 6 +/- 3); 30 age-matched controls (65 +/- 14 years) and 16 patients (59 +/- 12 years) with syncope not related to CSH were studied. Pharmacological stimulation of the carotid sinus was achieved by randomly administering bolus injections of nitroprusside and phenylephrine. Mechanical stimulation of the carotid sinus was performed by CSM applied for 5 s in the supine position and after 2 min at 60 degrees. A 60 degree low-dose isoproterenol head-up tilt test (HUTT) was also performed for a total duration of 30 min. RESULTS: Carotid sinus hypersensitivity was elicited by CSM in the supine position in seven (8.7%) patients, two (6.6%) controls and one (6.3%) patient with syncope unrelated to CSH, compared with 48 (60%) patients, two (6.6%) controls and one (6.3%) syncope unrelated to CSH patient after 60 degree HUTT, increasing the diagnostic yield by 51%. Baroreceptor gain was significantly reduced in the CSH group. Head-up tilt test was positive in 12 (25%) patients with CSH, two (6.6%) controls and two (12%) with documented syncope but not positive in any of the patients in which syncope remained unexplained. Diagnostic accuracy was enhanced by 38% (31% supine vs. 69% upright) when CSM was performed at 60 degrees. CONCLUSIONS: CSH was documented in 68% of patients, 8.7% in the supine position and 60% in the upright position. Sensitivity was increased by 51%, and diagnostic accuracy was enhanced by 38% by performing CSM in the upright position. Decreased baroreceptor gain was documented and may play a role in the pathophysiology of CSH.     

Prevalence of hypotensive disorders in older patients with a pacemaker in situ who attend the Accident and Emergency Department because of falls or syncope.

AIMS: To ascertain the proportion of adults with a pacemaker in situ attending the Accident and Emergency Department because of syncope or unexplained falls and the cause of index symptoms in these patients, including the prevalence of hypotensive syndromes. METHODS AND RESULTS: Patients presenting to the Accident and Emergency Department with unexplained syncope or non-accidental falls, who had a pacemaker in situ, were studied. Eligible patients had cardiovascular assessment (morning orthostatic blood pressure measurement, heart rate and BP measurements during carotid sinus stimulation (supine and upright), head-up tilt at 70 degrees for 40 min), assessment of haemodynamics during fixed mode pacing and gait and balance assessment. Of 5863 patients screened, 13.5% had unexplained syncope or a non-accidental fall; of these only 3% (26 patients) had pacemakers in situ. Of 18 study patients (82 +/- 8 years), 10 were female. Sixteen had a hypotensive diagnosis. Seven had more than one attributable hypotensive diagnosis. Five of 13 with vasodepressor carotid sinus syndrome had no previous diagnosis of carotid sinus hypersensitivity. No patients had vasovagal syncope induced during passive head-up tilt testing. CONCLUSION: It is rare for patients who attend the Accident and Emergency Department because of syncope or unexplained falls to have a pacemaker in situ. In those who do, hypotensive disorders are a common finding.     

Orthogeriatrics service for hip fracture patients in Dunedin Hospital: Achieving standards of hip fracture care

PurposeTo evaluate the orthogeriatrics service (consult liaison provided by geriatricians on an orthopedics ward) for hip fracture patients in Dunedin Hospital and to assess how well standards of hip fracture patient care were achieved. These standards (adapted from British Orthopaedics Association) include admission to ward within 4 hours, surgery within 48 hours, assessment and care to reduce pressure ulcer risk, access to orthogeriatrics services, and secondary prevention of falls and osteoporotic fractures.MethodsThis retrospective audit reviewed patients above age 65 years admitted to the orthopaedic service in Dunedin Public Hospital with a neck of femur fracture between January 1, 2010, and December 31, 2010.ResultsThere were 144 patients with median age of 86 years. 24.5% were admitted to the Orthopaedics ward within 4 hours: 70.8% had surgery within 48 hours and 73.6% had pressure ulcer assessment completed as per our hospital protocol. One-third was seen by the orthogeriatrics team on the day of surgery or earlier. History of falls was not documented in about one third of patients. Only 20.8% had postural blood pressure measured, and 35.6% of those discharged home had a home visit. About 30% did not have documentation of previous fractures, and one-quarter were not assessed for consideration of bisphosphonate therapy. Inpatient mortality was 9%.ConclusionsSeveral areas for improvement were identified from this retrospective study. Suggestions for achieving the standards of hip fracture care are provided. Further audit after implementing these changes is recommended.     

Enhanced vagal activity and normal arginine vasopressin response in carotid sinus syndrome: implications for a central abnormality in carotid sinus hypersensitivity

The relation between arginine vasopressin and vagal activity in carotid sinus syndrome was studied in 10 patients and 17 age matched controls using head up tilt as a stimulus. Of the controls, seven had unexplained syncope and 10 were healthy elderly subjects with no previous history of syncope. Subjects were studied supine for 45 min and thereafter during 120 min head up tilt to 40 degrees. Phasic arterial pressure and heart rate were monitored throughout. Serum was sampled at frequent intervals to measure arginine vasopressin, noradrenaline, and adrenaline concentrations. Seventy per cent of carotid sinus patients had vasovagal syncope at (mean(SD)) 25(4) min after tilt compared with 43% of subjects with unexplained syncope and one healthy elderly control. The maximum (mean(SD)) fall in systolic blood pressure and heart rate was 70(20) mmHg and 20(7) beats.min-1 (p less than 0.001 and p less than 0.01 respectively). Arginine vasopressin, noradrenaline, and adrenaline concentrations rose significantly in syncopal subjects (p less than 0.001, p less than 0.01, and p less than 0.05 respectively). Changes in systolic blood pressure, heart rate, and hormone concentrations were similar for patients with carotid sinus syndrome and control subjects. For those who completed the tilt period without the development of symptoms, systolic blood pressure and arginine vasopressin and adrenaline concentrations were unchanged, whereas noradrenaline concentrations and heart rate rose significantly. Vasovagal activity is thus appreciably increased in carotid sinus syndrome. Furthermore, the afferent limb of the carotid sinus reflex appears to be intact in patients with carotid sinus syndrome since the pattern of arginine vasopressin release was not different from controls.(ABSTRACT TRUNCATED AT 250 WORDS)     

Prevalence and One-year Outcome of Carotid Sinus Hypersensitivity in Unexplained Syncope: A Prospective Cohort Study from South India

Background

Carotid sinus syndrome accounts for one third of patients who presents with unexplained syncope. Prevalence of carotid sinus hypersensitivity (CSH) in Indians has not been studied till now.

SAFE PACE 2: Syncope and Falls in the Elderly--Pacing and Carotid Sinus Evaluation: a randomized controlled trial of cardiac pacing in older patients with falls and carotid sinus hypersensitivity.

SAFE PACE is a multicentre randomized controlled trial to assess the efficacy of dual-chamber pacing in older patients with carotid sinus hypersensitivity and recurrent unexplained falls. Patients are eligible if they have had two or more unexplained falls (+/- up to one syncope) and if they have a cardio-inhibitory response (>3 s asystole) to carotid sinus massage. Patients will be randomized to receive either a Medtronic Kappa 700(Europe)/Kappa 400(North America) pacemaker or an implantable loop recorder (ILR)(control group). Patients will be required to complete weekly fall diaries. The primary outcome measure is the number of patients who fall in the 24-month follow-up period. Recruitment began in October 1998 and continues for 12 months; the follow-up is for 24 months.     

Carotid sinus syndrome and falls in older adults

Retrospective and circumstantial evidence supports an overlap between symptoms of falls and syncope in older adults. Because of this overlap, 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. One third attended because of a fall; one in five fallers had unexplained falls, and one third of these had carotid sinus hypersensitivity, of whom one half had a cardioinhibitory or mixed response that may be expected to respond to cardiac pacing. In a randomized, controlled trial of a subset of these patients, cardiac pacing was shown to significantly reduce subsequent fall rates by two thirds and syncopal rates during 1-year follow-up. The current pacing rate for carotid sinus syndrome is much higher in our practice than in other series because our facility is dedicated to falls and syncope in older subjects who have direct access to referring physicians and family practitioners. Of the implants in our region, 24% are for carotid sinus syndrome, compared with 43% for atrioventricular block, 20% for sick sinus syndrome, and 12% for atrial fibrillation. These rates do not include pacing in patients who fall, but rather reflect pacing rates consistent with American College of Cardiology guidelines for carotid sinus syndrome, such as recurrent syncope. These preliminary results from a local explanatory study are now being tested in a multicenter study entitled Syncope and Falls in the Elderly: Pacing and Carotid Sinus Evaluation (SAFE-PACE II).     

Intensive physical training in geriatric patients after severe falls and hip surgery

BACKGROUND: Intensive exercise training can lead to improvement in strength and functional performance in older people living at home and nursing home residents. There is little information whether intensive physical exercise may be applicable and effective in elderly patients suffering from the acute sequelae of injurious falls or hip surgery. OBJECTIVE: To assess the feasibility, safety and efficacy of intensive, progressive physical training in rehabilitation after hip surgery. DESIGN: Prospective, randomised, placebo-controlled intervention study of a 3-months training intervention and a 3-months' follow-up. SETTING: Physical training 6-8 weeks after hip surgery. SUBJECTS: Twenty-eight (15 intervention, 13 control) elderly patients with a history of injurious falls admitted to acute care or inpatient rehabilitation because of acute fall-related hip fracture or elective hip replacement. METHODS: Progressive resistance and functional training to improve strength and functional performance. RESULTS: No training-related medical problems occurred in the study group. Twenty-four patients (86%) completed all assessments during the intervention and follow-up period. Adherence was excellent in both groups (intervention: 93, 0+/-13, 5% versus control: 96, 7+/-6, 2%). Training significantly increased strength, functional motor performance and balance and reduced fall-related behavioural and emotional problems. Some improvements in strength persisted during 3-months follow-up while other strength variables and functional performances were lost after cessation of training. Patients in the control group showed no change in strength, functional performance and emotional state during intervention and follow-up. CONCLUSIONS: Progressive resistance training and progressive functional training are safe and effective methods to increase strength and functional performance during rehabilitation in patients after hip surgery and a history of injurious falls. Because part of the training improvements were lost after stopping the training, a continuing training regime should be established.     

Syncope-related falls in the elderly

Age-related physiological impairments of heart rate, blood pressure and cerebral blood flow, in combination with comorbid conditions and concurrent medications, account for an increased susceptibility to syncope in older adults. Common causes of syncope are orthostatic hypotension, neurally-mediated syncope (including carotid sinus syndrome) and cardiac arrhythmias. A high proportion of older patients with cardiovascular syncope present with falls and deny loss of consciousness. Patients who are cognitively normal and have unexplained falls should have a detailed cardiovascular assessment. (J Geriatr Cardiol 2005; 2 (2): 74-83).     

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.     

A hypothesis: the causes of hip fractures

Neither age-related osteoporosis nor the increasing incidence of falls with age sufficiently explain the exponential increase in the incidence of hip fracture with aging. We propose that four conditions must be satisfied in order for a fall to cause a hip fracture: (a) the faller must be oriented to impact near the hip; (b) protective responses must fail; (c) local soft tissues must absorb less energy than necessary to prevent fracture, and (d) the residual energy of the fall applied to the proximal femur must exceed its strength. All of these events become more likely with aging and lead to an exponential rise in the risk of hip fracture with advancing age. This model also suggests that a combination of measurements of neuromuscular function and of bone strength may be the most accurate approach to assessing the risk of hip fracture.     

Carotid sinus syndrome--clinical characteristics in elderly patients.

Carotid sinus massage was carried out on 130 consecutive patients referred for investigation of dizziness, syncope or unexplained falls. Carotid sinus syndrome was diagnosed in 33 for whom no other cause of symptoms was identified. Right-sided hypersensitivity was more frequent than left-sided. Thirty per cent identified a prodrome before syncope and 30% had retrograde amnesia for the event. In 52%, symptoms were precipitated by head movement and in 48% by vagal stimuli. Seven described 'drop attacks' but symptoms were reproduced with carotid sinus massage during head-up tilt. Injuries, including fractured neck of femur, were sustained by the majority. Carotid sinus massage should be performed routinely on all elderly patients who have symptoms of unexplained dizziness, falls or syncope. Cardiac pacing relieves syncopal symptoms in those with a predominant cardio-inhibitory response and recurrent syncope.     

Fracture of the femur in old age: A two-centre study of associated clinical factors and the cause of the fall

All patients with fractured neck of the femur admitted to hospitals in two areas (North London and Manchester) in a period of one year have been examined--a total of 384 patients. Compared to control groups of similar age, the older fracture patients showed a higher prevalence of chronic brain syndrome, they were in poorer physical state and their skinfold thickness was less. They also had more unrecognized visual disorders. Those who were younger had a higher prevalence of stroke than comparable controls. The type of fall leading to the fracture varied with age--tripping was the commonest cause in the younger patients the 'drop attacks' in the older. Both stroke and partial sightedness were associated with falls due to loss of balance. The older patients had a very high prevalence of pyramidal tract abnormality associated with chronic brain syndrome--and it appears that these demented patients fall not because of mental confusion but because of associated motor abnormalities. Extra-capsular fractures occur in older patients. They are more likely to have a history of falls but previous fracture is equally common at this age in the fracture and control series.     

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.     

Carotid Sinus Hypersensitivity in Patients Undergoing Coronary Arteriography:

Carotid Sinus Hypersensitivity and Atherosclerosis. Introduction: The purpose of the present investigation was to study the precise relationship between carotid sinus hypersensitivity (CSH) and both the severity of carotid atherosclerosis and the extent of coronary artery disease in patients who were referred for evaluation for suspected ischemic heart disease.
Methods and Results: Duplex echocardiography and coronary angiography were used to assess carotid and coronary artery atherosclerosis in 130 consecutive patients. Carotid sinus stimulation was performed before coronary arteriography with simultaneous recordings of the ECG and aortic pressure. Coronary artery disease was present in 103 patients (79%). Thirty patients (23.08%) had one-vessel disease (1-VD), 31 (23.85%) had 2-VD, 29 (22.31%) had 3-VD, and 13 patients (10%) had left main coronary artery disease. Carotid artery atherosclerosis was present in 100 patients (76.92%) and carotid disease (diameter stenosis ≥ 50%) was present in 24 patients (18.46%). CSH was found in 33 patients (25%). The incidence of CSH was 9% in patients with carotid stenosis 1%-15%, 17% in patients with stenosis 16%-49%, 85% in patients with stenosis 50%-79%, and 100% in patients with stenosis ≥ 80%. The incidence of CSH was 11%, 17%, 23%, 34%, and 62% in patients with no VD, 1-VD, 2-VD, 3-VD, and left main coronary artery disease, respectively. Stepwise multiple logistic regression analysis revealed that carotid disease and left main coronary artery disease were the most significant determinants of CSH (P < 0.001 and P = 0.013, respectively).
Conclusion: The incidence of CSH increased in proportion to the severity of carotid and coronary atherosclerosis. These data provide evidence that CSH is closely related to severe carotid atherosclerosis or left main coronary artery disease in patients being evaluated for suspected ischemic heart disease.