Full text of DOI:10.1002/clc.4960250406

Clin. Cardiol. 25, 161–166 (2002)
Exaggerated Carotid Sinus Massage Responses Are Related to Severe Coronary
Artery Disease in Patients Being Evaluated for Chest Pain
COSTAS P. TSIOUFIS, M.D., FESC, IOANNIS E. KALLIKAZAROS, M.D., FESC, KONSTANTINOS P. TOUTOUZAS, M.D.,
CHRISTODOULOS I. STEFANADIS, M.D., FACC, PAVLOS K. TOUTOUZAS, M.D., FACC
Department of Cardiology, Hippokration Hospital, University of Athens, Athens, Greece
Summary
Background: Previous studies have reported that carotid si-
nus massage responses are associated with advancing age and
carotid or coronary artery disease.
Conclusion: In patients being evaluated for suspected is-
chemic heart disease, carotid sinus massage responses are re-
lated to severe coronary disease. The absence of hypersensitiv-
ity may reflect absence of left main stem disease.
Hypothesis: This study was undertaken to investigate
the potential role of carotid sinus hypersensitivity as a marker
for the presence of coronary artery disease, and especially left
main stem disease, in patients who were referred for evalua-
tion of chest pain.
Key words: carotid sinus hypersensitivity, left main stem
coronary artery disease
Methods: Toward this end, carotid sinus stimulation with si-
multaneous recordings of the electrocardiogram and aortic
pressure was performed before coronary arteriography in 150
selected consecutive patients (mean age 59.4 ± 9 years) who
were referred for evaluation of chest pain.
Introduction
The carotid sinus as a part of the baroreceptor system plays
an important role in the normal reflex regulation of the car-
1, 2
diovascular system. Carotid sinus massage (CSM) fre-
quently serves as an important diagnostic aid in deciphering
cardiac arrhythmias and has been regarded as a useful thera-
peutic maneuver in relieving anginal pain or acute pulmonary
edema in patients with coronary artery disease (CAD) or hy-
Results: Coronary artery disease was present in 118 patients
(78.7%); of these, 35 had single-vessel disease, 35 had double-
vessel disease, 33 had triple-vessel disease, and 15 had left
main stem with or without such vessel disease. Carotid sinus
hypersensitivity was found in 40 patients (26.6%). The inci-
dence of hypersensitivity in patients with single-, double-, or
triple-vessel disease and left main stem disease was 8.5, 14.2,
3–5
pertension. In addition, previous studies have suggested
that carotid sinus hypersensitivity (CSH) is associated with
6–8
advancing age and coronary or carotid artery disease. The
aim of the present study was to assess the possible relation-
ship between CSH and the presence or absence of severe
CAD in patients who were referred for evaluation of chest
pain by coronary angiography.
57.5, and 73.3%, respectively. Stepwise multiple logistic re-
gression analysis revealed that left main stem disease was sig-
nificantly and independently related to the presence of carotid
sinus hypersensitivity (p < 0.05). In addition, the presence of
hypersensitivity had 73.3% sensitivity, 86.2% specificity, and
96.3% negative predictive value for the presence of left main
stem disease.
Subjects and Methods
Study Population
The study group included 210 consecutive patients, in sinus
rhythm, who were referred for coronary angiography for eval-
uation of chest pain and/or abnormal noninvasive test results
suggestive of ischemic heart disease.
From our study we excluded (1) patients in whom CSM
could induce risk (such as patients with recent cerebrovascular
infarction, ulcerated carotid atherosclerotic plaque, or total
carotid artery occlusion detected by ultrasonography, uncon-
trolled hypertension, and unstable angina or recent acute my-
ocardial infarction), and (2) patients in whom the interpreta-
Address for reprints:
Dr. Costas Tsioufis
4
1
Athanasiou Diakou Street
5127 Melissia
Athens, Greece
Received: November 13, 2000
Accepted with revision: July 16, 2001

162
Clin. Cardiol. Vol. 25, April 2002
tion of coronary angiography was obscured (such as patients
with coronary bypass graft or percutaneous transluminal coro-
nary angioplasty). Also, we excluded patients with cardiomy-
opathy, valvulopathy, sinus dysfunction, or persistent sinus
bradycardia below 50 beats/min and any systemic disease.
Finally, 150 patients fulfilling the above criteria were selected.
After a detailed history, all patients underwent a physical
examination, chest x-ray, electrocardiogram (ECG), and an ul-
trasound examination of the heart and carotid arteries. The in-
stitutional ethics committee of our hospital approved the study
protocol that included an evaluation of risk factors for car-
diovascular diseases, carotid sinus massage, and coronary an-
giography—left ventriculography. Written informed consent
was obtained from all patients after a detailed description of
the procedure.
fashion: we began our stimulation basically with a light touch
to observe the response and then we increased the strength of
the stimulation in successive attempts. If there was no re-
sponse, pressure was increased for an additional 5 s. The di-
rection of the compression in the carotid bifurcation was usu-
ally against the vertebral spine. We made sure that the pressure
applied did not occlude the carotid artery by simultaneous pal-
pation of the ipsilateral temporary artery pulse. The massage
was terminated prematurely only if an asystole longer than 3 s
resulted. To reestablish control conditions after the massage of
the sinus was completed, we repeated the CSM on the other
side 2 min later.
The massage was carried out by the same investigator who
was blinded to clinical history of the patients, including the re-
sults of the ischemic workup, with the same intensity in order
to maintain uniformity of stimulus. Simultaneous recording of
the aortic pressure and the ECG started 10 s before and contin-
ued during and after CSM until arterial pressure and heart rate
returned to baseline levels.
The following variables from the ECG and the aortic pres-
sure recordings were measured (Fig. 1): (1) Max R-R (in s):
the longest R-R interval on the ECG recording during carotid
sinus massage. (2) Max AoP Fall (in mmHg): the difference
between baseline systolic aortic pressure (average of 5 con-
secutive beats) immediately before CSM and the lowest sys-
tolic pressure during massage or immediately after massage
termination.
Evaluation of Risk Factor Variables
The risk factor variables that were evaluated in this study in-
cluded age, hypercholesterolemia (defined as total plasma
cholesterol > 210 mg/dl in the previous 12 months, or docu-
mented hypercholesterolemia requiring lipid-lowering drug
therapy), hypertension (coded as present if there was any histo-
ry of high blood pressure or if the blood pressure measured at
the hospital had at least twice exceeded 150 mmHg systolic or
95 mmHg diastolic), diabetes mellitus (defined as patient his-
tory of diabetes requiring treatment, or Hb A1c value >8%),
smoking behavior (if the patient had smoked for > 20 pack-
years), and family history (coded as positive if a first degree
According to their exaggerated response to CSM, our
patients were classified into three types: patients with cardio-
inhibitory type (characterized by the provocation of ventricu-
lar asystole of a 3 s minimum duration), vasodepressor type
(characterized by the provocation of a decrease in systolic
aortic pressure of at least 50 mmHg or a decrease of 30
mmHg in the presence of neurologic symptoms), and mixed
type (a combination of cardioinhibitory and vasodepressor
9
relative had had a serious coronary event before the age of 60).
Carotid Sinus Massage
Carotid sinus massage was performed in the catheterization
laboratory, after overnight fasting, just before coronary an-
giography. Cardiovascular medications were discontinued for
at least five drug half lives before CSM was performed and
premedication was not administered. A pigtail, fluid-filled
catheter was advanced to the ascending aorta through a 7F
sheath placed into the right femoral artery in order to record
the aortic pressure.
A temporal pacemaker electrode was advanced to the right
ventricle through a 5F sheath placed into the right femoral vein
and was on standby. Two surface ECG leads were also moni-
tored continuously. Carotid sinus massage was performed 20
min after the instrumentation and before coronary angiogra-
phy to allow patients to relax and for hemodynamic parame-
ters to stabilize, and also to exclude any effect of the contrast
medium on the carotid sinus reflex. Electrocardiogram and
aortic pressure tracings were recorded simultaneously on a
Honeywell multichannel strip chart recorder (Honeywell
Medical Electronic Division, New York, N.Y., USA) at paper
speeds of 25 and 50 mm/s.
2, 3, 10, 11
types).
In patients who exhibited asystole > 3 s, the
CSM was repeated after the intravenous administration of
0.02 mg/kg atropine in order to eliminate heart rate slowing
and to allow the differentiation of the pure cardioinhibitory
type, the vasodepressor type, or the mixed type.
To test the reproducibility of CSM responses, we repeated
the CSM in 15 patients 30 min after the first massage and be-
fore coronary angiography. We found a significant correlation
(r = 0.80) between the results of the first and second massage as
far as both normal and exaggerated responses are concerned.
Coronary Angiography
Coronary angiography and left ventriculography were per-
formed using the standard Judkins technique. The percentage
of diameter stenosis was calculated by quantitative coronary
angiography with a commercially available automated coro-
nary analysis system (DCI-S, Phillips Medical System,
Bothell, Wash., USA). Coronary artery disease was defined
as diameter stenosis of > 50% in at least one major coronary
artery. According to the number of diseased vessels, our pa-
tients were classified into the following five groups : Group 1:
The technique used to perform the test has been previously
2, 3, 6
described.
In brief, with the patient in the supine position,
during normal respiration, the carotid sinus region was identi-
fied and the massage was gently applied for 5 s in a progressive

C. P. Tsioufis et al.: Carotid sinus hypersensitivity and coronary disease
163
Carotid sinus massage
ECG
Max R-R
Max AoP fall
Aortic pressure
(A)
(B)
(C)
FIG. 1 (A) Recordings of simultaneous intra-aortic pressure and two-lead electrocardiogram (ECG) before, during, and after carotid sinus mas-
sage in a patient. With the onset of right carotid massage, there is an increased responsiveness regarding the heart rate and the aortic pressure. See
text for definitions of intervals. (B) Coronary angiography of this patient shows left main stem coronary artery disease and triple-vessel disease
in the left anterior oblique with cranial angulation view.
no vessel disease, Group 2: single-vessel disease, Group 3:
double-vessel disease, Group 4: triple-vessel disease, and
Group 5: left main stem (LMS) CAD (with or without such
vessel disease).
Coronary Angiographic Findings
Coronary angiography revealed CAD in 118 patients
(78.7%). In particular, 35 patients (23.3%) had single-vessel
disease, 35 patients (23.3%) had double-vessel disease, 33 pa-
tients (22 %) had triple-vessel disease, and 15 patients (10%)
had LMS-CAD. The remaining 32 patients (21.3%) had coro-
nary arteries without critical stenosis. Furthermore, the ejec-
tion fraction was 52 ± 10 % (range 25–75).
Statistical Analysis
Data were expressed as mean ± standard deviation. For
comparison between means, the paired Student’s t-test or the
chi-square test was used where appropriate. Logistic regres-
sion analysis was applied to identify possible predictors of
a dichotomous dependent variable. A value of p < 0.05 was ac-
cepted as statistically significant.
Carotid Sinus Massage Responses
The procedure of CSM was carried out without any mor-
bidity. The mean values of max R-R interval and max AoP
fall was 1.63 s (range 0.5–13) and 30.8 mmHg (range 5–70),
respectively.
The CSM responses, according to the massage on the left
and the right carotid sinus, did not differ (p = 0.38). Almost all
patients (147 of the 150) had some heart rate slowing and a de-
crease in blood pressure with CSM.
Carotid sinus hypersensitivity was found in 40 patients
(26.6%). The mean values of the Max R-R interval was 3.84 s
(range 0.60–13.00) and Max AoP fall was 43.5 mmHg (range
20–70).
Results
Clinical Features
The study group consisted of 127 men and 23 women with
a mean age of 59.4 years (range 34–79). Of these, 91 (60.7%)
were smokers, 64 (42.7%) had hypercholesterolemia, 63
(42%) had hypertension, 35 (23.3%) had diabetes mellitus,
and 22 (14.7%) had positive family history.

164
Clin. Cardiol. Vol. 25, April 2002
TABLE I Clinical characteristics of the hypersensitive population
1
00.0
90.0
80.0
70.0
60.0
50.0
40.0
30.0
Age (years)
Sex (male/female)
Smoking (%)
Hypertension (%)
Positive family history (%)
Diabetes mellitus (%)
Hypercholesterolemia (%)
64.8 ± 8.11
34/6
28 (70.0)
17 (42.5)
10 (25)
7
3.3%
57.5%
10 (25)
29 (72.5)
1
4.2%
2
1
0.0
0.0
8.5%
6
.2%
0
.0
0
-VD
1-VD
2-VD
3-VD LMCAD
Cardioinhibitory type response was present in 29 patients
Extent of coronary artery disease
(
72.5%), vasodepressor type in 5 patients (12.5%), and mixed
type in 6 patients (15%). Only three of the patients with CSH
had a history of dizziness and confusion interfering with their
daily activity. In these patients, CSM was sufficient to repro-
duce spontaneous symptoms and they were found to belong to
the cardioinhibitory type. The clinical characteristics of these
patients are presented in Table I. We noticed a stepwise in-
crease in the percentage of hypersensitive patients as the age
increased: The incidence of CSH was 15.4% in patients aged
FIG. 2 Plot showing distribution of patients with carotid sinus hy-
persensitivity (CSH) as a function of the extent of coronary artery
disease. 0-VD = coronary arteries without critical stenosis, 1-VD =
single-vessel disease, 2-VD = double-vessel disease, 3-VD = triple-
vessel disease, LMCAD = left main coronary artery disease.
the presence of CSH (Table II). Moreover, CSM responses
show a satisfactory sensitivity (73.3%) and specificity (78.5%)
and a high negative predictive value (96.3%) for the presence
of LMS -CAD (Table III).
4
0–49 years, 25.9% in patients 60–69 years, and 52.9% in pa-
tients age 70–79 years.
Relation of Carotid Sinus Responses to Coronary
Artery Disease
Discussion
The incidence of CSH in patients without CAD was 6.2%
(2/32) while in patients with CAD it was 32.2% (38/118).
Accordingly, CSH was present in 3 of 35 patients (8.5%) with
single-vessel disease, in 5 of 35 patients (14.2%) with double-
vessel disease, in 19 of 33 patients (57.5%) with triple-vessel
disease, and in 11 of 15 patients (73.3%) with LMS-CAD
In this study we reported the close relationship between
CSM responses and the severity and extent of atherosclerosis
in the coronary arteries in patients evaluated for suspected is-
chemic heart disease. The major finding of our study was that
CSH is independently related to LMS-CAD and furthermore,
in this study population, the absence of CSH reflects the ab-
sence of LMS-CAD.
(
Fig. 2).
Forward stepwise logistic regression analysis revealed that
only the presence of LMS-CAD was independently related to
TABLE II Stepwise multiple logistic regression coefficients for the relationship between night variables and carotid sinus hypersensitivity
Variables
Coefficient (b)
Wald
6.46
p Value
0.011
Left main stem coronary artery disease
Constant
1.99 ± 0.78
ꢀ2.45 ± 0.34
The variables age, male sex, smoking, diabetes mellitus, hypertension, heredity, hypercholesterolemia, triple-vessel coronary disease, and ejec-
tion fraction did not enter the equation, according to the selection criteria (probability for entry < 0.05, probability of removal > 0.01).
TABLE III Carotid sinus hypersensitivity as predictor for coronary artery disease and left main stem coronary disease
Sensitivity
Specificity
Positive predictive value
Negative predictive value
Prediction of
Coronary artery disease (%)
Left main stem coronary disease (%)
32.2
73.3
93.7
78.5
95
27.5
27.2
96.3

C. P. Tsioufis et al.: Carotid sinus hypersensitivity and coronary disease
165
Carotid Sinus Massage Responses and
Atherosclerotic Disease
the decreased baroreflex sensitivity and resetting of carotid
sinus baroreceptors in atherosclerosis. Apart from the above-
mentioned mechanical component, the accompanied endothe-
lial dysfunction with the resulting defect in endogenous pro-
duction of prostacyclin enhances formation of oxygen-free
radicals and platelet aggregation and contributes to the im-
Previous studies have reported an association between CSH
5, 6
and atherosclerotic vascular disease. Brown et al. were the
first to show that the exaggerated response to CSM in the pres-
ence of symptomatic CAD is associated with the total CAD
18, 22–24
paired baroreceptor activity.
Keeping in mind that the
11
score; however, possible additional associations between
CSM responses and the severity of CAD have not been well
addressed. To investigate this issue further, we focused our at-
tention on the exact relation between CSH and LMS-CAD.
Thus, in the present study using CSM in a series of consecutive
patients evaluated for suspected ischemic heart disease, the in-
cidence of CSH was increased in proportion to the severity of
CAD: from 6% in the patients with no vessel disease to 57 and
severity of carotid artery disease is strongly and consistently
associated with the coronary status and especially with LMS-
25, 26
CAD,
we suggest that our findings are in agreement with
the above concept.
Limitations
Several factors may have limited the apparent strength of the
relation we found between CMS responses and LMS-CAD.
First, we studied a group of consecutive patients who were re-
ferred for coronary angiography for suspected ischemic heart
disease. This selection bias means that our findings regarding
the relation of carotid sinus responses with the presence of
LMS-CAD are relevant only to this special group of patients
and may not be applicable to the general population.
7
3% in patients with triple-vessel disease and LMS-CAD, re-
spectively. In addition, carotid sinus responses appear to be re-
lated to the absence of LMS-CAD, since CSH had a high neg-
ative predictive value (96.3%) for the presence of LMS-CAD.
Indications of Carotid Sinus Stimulation
In the past, CSM has been considered to be a useful diag-
nostic and therapeutic maneuver in patients with angina pec-
toris.
suggest that carotid sinus pressure may relieve anginal pain.
Lown and Levine reported the diagnosis of CAD in patients in
their late thirties and early forties who complained of atypical
chest pain, exhibited nonspecific alterations in ST segments
and T-wave complexes, and responded to mild and brief CSM
Also, although we discontinued the cardiovascular medica-
tion for at least five drug half lives before CMS was per-
formed, we cannot exclude the possibility that the observed
carotid sinus responses have been influenced by the induced
hyperadrenergic state in a group of patients who were previ-
3, 5, 12, 13
In 1928, Wassermann and Weber were the first to
5
20
ously being treated with beta blockers. Second, regardless of
the method of analysis, coronary angiography frequently un-
derestimates the severity of atherosclerotic disease, although it
is a reasonable method for measuring the extent and severity of
CAD. Also, the classification of CAD extent based on the
number of diseased vessels may not be as precise as other spe-
cific indices such as the Gensini score. However, this classifi-
cation is very common in every day clinical practice and con-
sequently the relation of CSH to the diseased vessels is of
practical value. Finally, as it has been suggested by others in
similar studies, the reproducibility of the response to CSM
3
with partial or complete heart block. Since LMS-CAD is a
disease of high morbidity and mortality, evidence derived
from CSM responses could be very helpful in the evaluation
and treatment of these patients until the definite diagnosis can
be made by cardiac catheterization. Obviously, CSM cannot
replace the already existing, noninvasive tests for the evalua-
tion of CAD, such as stress test, echo-dobutamine, and so
forth, and probably the greatest clinical value of CSM is clari-
fying the type or the mechanism of different rhythm distur-
bances and confirming the presence of hypersensitivity.
Taken into consideration that manipulation of the carotid sinus
can be accomplished at the bedside and, when done properly,
carries little risk, we suggest that CSM is a simple, safe, non-
invasive test, at bedside, that may provide useful information
in everyday clinical practice in selected patients under evalua-
tion for chest pain.
2, 10
3, 14, 15
may not be as high; however, in this study, we observed a
good reproducibility of the CMS responses either performed
invasively or noninvasively. A possible explanation for our
good reproducibility is that we used a standardized stimulation
protocol.
16
Conclusion
Mechanisms of Carotid Sinus Hypersensitivity
In patients who were referred for evaluation of chest pain,
CSM responses are significantly related to the presence of
LMS-CAD. The absence of CSH may reflect absence of
LMS-CAD.
Although the mechanisms of the relation between athero-
sclerotic disease and exaggerated carotid sinus responses are
not fully understood, it is currently believed that the bulk of the
abnormalities in the carotid sinus reflex is present in the central
nervous system, especially in the cardiovascular regulation
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