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Overview of Exercise Stress Testing


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Exercise stress testing is a non-invasive, safe and affordable screening test for coronary artery disease (CAD), provided there is careful patient selection for better predictive value. Patients at moderate risk for CAD are best served with this kind of screening, with the exception of females during their reproductive period, when a high incidence of false positive results has been reported. Patients with a high pretest probability for CAD should undergo stress testing combined with cardiac imaging or cardiac catheterization directly. Data from the test, other than ECG changes, should be taken into consideration when interpreting the exercise stress test since it has a strong prognostic value, i.e. workload, heart rate rise and recovery and blood pressure changes. Only a low-level exercise stress test can be performed early post myocardial infarction (first week), and a full exercise test should be delayed 4 to 6 weeks post uncomplicated myocardial infarction. The ECG interpretation with myocardial perfusion imaging follows the same criteria, but the sensitivity is much lower and the specificity is high enough to overrule the imaging part.
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Ann Saudi Med 26(1) January-February 2006
From the Department of
Cardiovascular Disease, King
Faisal Specialist Hospital and
Research Centre, Riyadh, Saudi
Suleiman M. Kharabsheh, MD
Consultant Cardiologist
Department of Cardiovascular
King Faisal Specialist Hospital and
Research Centre
MBC 16
P.O. Box 3354
Riyadh 11211
Saudi Arabia
Tel: +966-1-442-7472
Fax: +966-1-442-7478
Accepted for publication
February 2004
Ann Saudi Med 2006;26(1):1-6E
xercise stress testing has been used for decades as a noninvasive
test to diagnose and risk stratify coronary artery disease (CAD).
However, it lacks adequate sensitivity, which nevetheless de-
pends on the pretest probability of CAD in the population tested. e
overall sensitivity has ranged from 60% to 70% with a specificity of
Due to the innumerable criteria set for the EKG stress test
interpretation and reporting, a lot of confusion arises between institu-
tions. To make it easier on the practitioner at our institution, we have
adopted the criteria outlined in this review for interpretation of test
Indications and safety of exercise testing
Although exercise testing is generally a safe procedure, both myocardial
infarction and death have been reported and can be expected to oc-
cur at a rate of up to 1 per 2500 tests. Good clinical judgment should
therefore be used in deciding which patients should undergo exercise
testing. Common indications and contraindications are listed in Table
1 e prognosis of the individual tested is not only linked to the result
of the test whether it is positive or negative, but also depends on the
exercise capacity, heart rate rise, heart rate recovery and blood pressure
rise and recovery.
Exercise capacity is based on metabolic equivalents (MET) achieved,
(one MET is defined as 3.5 mL O2 uptake/kg per min, which is the
resting oxygen uptake in a sitting position). Less than 5 METS is poor,
5-8 METS is fair, 9-11 METS is good, and 12 METS or more is ex-
cellent. An inability to exercise >6 minutes on the Bruce protocol, or
Overview of Exercise Stress Testing
Suleiman M Kharabsheh, Abdulaziz Al-Sugair, Jehad Al-Buraiki, Joman Farhan
Exercise stress testing is a non-invasive, safe and affordable screening
test for coronary artery disease (CAD), provided there is careful patient
selection for better predictive value. Patients at moderate risk for CAD
are best served with this kind of screening, with the exception of fe-
males during their reproductive period, when a high incidence of false
positive results has been reported. Patients with a high pretest prob-
ability for CAD should undergo stress testing combined with cardiac im-
aging or cardiac catheterization directly. Data from the test, other than
ECG changes, should be taken into consideration when interpreting the
exercise stress test since it has a strong prognostic value, i.e. workload,
heart rate rise and recovery and blood pressure changes. Only a low-
level exercise stress test can be performed early post myocardial infarc-
tion (first week), and a full exercise test should be delayed 4 to 6 weeks
post uncomplicated myocardial infarction. The ECG interpretation with
myocardial perfusion imaging follows the same criteria, but the sensi-
tivity is much lower and the specificity is high enough to overrule the
imaging part.
Ann Saudi Med 26(1) January-February 2006
an inability to increase heart rate (HR) to >85% of
maximum predicted heart rate (MPHR) are signifi-
cant indicators of increased risk of coronary events
with a 5-year survival ranging from 50% to 72%.
However, patients who attain >10 METS enjoy an
excellent prognosis regardless of the test result even
in the presence of known CAD, with a 5-year sur-
vival of 95%.
e heart rate should reach or exceed 85% of
MPHR calculated according to the formulae,
MPHR=220-age. e HR rises prortionately with
the intensity of the workload. An excessive rise in
rate results primarily from a reduced stroke vol-
ume, which in turn is often caused by physical de-
conditioning, cardiac disease or arrhythmias like
atrial fibrillation or supraventricular tachycardias
and other noncardiac abnormalities like anemia and
hypovolemia. In these situations the HR reaches its
peak early, which limits maximum exercise capac-
ity. An impaired chronotropic response to exercise
as defined by failure to achieve 85% of MPHR
and/or a low chronotropic index (<0.8 of heart rate
reserve at peak exercise) caused by sinus node dys-
function, medications like β−blockers, or ischemia,
are occasionally associated with increased mortality
and cardiac events even after adjusting for left ven-
tricular function and the severity of exercise-induced
myocardial ischemia.
e HR should decrease by at
least 12 beats in the first minute of recovery, which
is mediated through vagal reactivation. Otherwise,
recovery is considered abnormal, which has a bad
prognosis, with a 6-year mortality 2-3 times greater
than those with normal recovery.
BP should increase by at least 10 mm Hg during
exercise except in patients on antihypertensive treat-
ment where a blunted response is observed. Diastolic
blood pressure (DBP) exhibits little or no change
(<10 mm Hg) during exercise because of peripheral
vasodilatation. A sustained drop of SBP>10 mm Hg,
confirmed within 15 seconds, often indicates severe
left ventricular dysfunction and severe CAD and is
an indication to stop the test immediately and re-
fer for further evaluation and treatment (Table 2).
Failure to increase systolic blood pressure by 10 to
30 mm Hg during exercise testing is an independent
predictor of adverse outcome in patients after myo-
cardial infarction.
However, it is crucial to exclude
other causes that could cause a drop in SBP with
exercise without the presence of severe CAD or left
ventricular dysfunction, i.e. vasovagal syncope, cardi-
ac arrhythmias, left ventricular outflow obstruction
or hypovolemia. In addition, an abnormal BP recov-
ery, defined by the SBP at 3 minutes of recovery over
an SBP at 1 minute of recovery >1, is associated with
a greater likelihood of severe angiographic CAD.
An abnormal rise of SBP to a level > 214 mm
Hg in patients with a normal resting BP predicts an
increased risk for future sustained hypertension, esti-
mated at approximately 10% to 26% over the next 5
to 10 years.
However, in adults evaluated for CAD,
exercise hypertension is associated with a lower like-
lihood of angiographically severe disease and a lower
adjusted mortality rate on follow up.
Table 1. Common indications and contraindications for exercise stress testing.
Evaluating the patient with chest pain or dyspnea with other findings suggestive,
but not diagnostic of coronary artery disease (CAD)
• Risk stratification post-myocardial infarction
• Determining prognosis and severity of coronary artery disease
• Evaluating the effects of medical and surgical therapy
• Screening for latent coronary disease
• Evaluation of congestive heart failure
• Evaluation of arrhythmias
• Evaluation of functional capacity and formulation of an exercise prescription
• Evaluation of congenital heart disease
• Stimulus to a change in lifestyle
Contraindications (absolute)
• Very recent MI, < 3-4 days
• Unstable angina, not previously stabilized by medical therapy
• Severe symptomatic left ventricular dysfunction
• Life threatening dysrhythmias
• Severe aortic stenosis ( relative?)
• Acute pericarditis, myocarditis or endocarditis
• Acute aortic dissection
Contraindications (relative)
• Left main coronary stenosis
• Moderate stenotic valvular heart disease
• Electrolyte abnormalities
• Severe arterial hypertension (SBP>200 mmHg or DBP>110 mmHg)
• Tachyarrhythmias or bradyarrhythmias
• Hypertrophic cardiomyopathy and other forms of outflow tract obstruction
• Mental or physical impairment leading to inability to exercise adequately
• High-degree atrioventricular block
Ann Saudi Med 26(1) January-February 2006
Interpretation of the electrocardiogram
ST changes should be read at 60 to 80 ms from the
J point,
and the test should be considered positive
for ischemia if there is a 2 mm or more rapidly up-
sloping ST depression (when the slope is more than
1 mV/s) ,
a 1.5 mm or more slowly up-sloping
ST depression (when the slope is less than 1 mV/s)
(Figure 1), or a 1 mm or more horizontal or down
sloping ST depression (Figure 2, 3).
Ischemic ST-segment changes developing dur-
ing recovery from treadmill exercise in apparently
healthy individuals has adverse prognostic signifi-
cance similar to those appearing during exercise.
Resting ST-segment depression has been identified
as a marker for adverse cardiac events in patients
with and without known CAD.
end points of 2 mm of additional exercise-induced
ST-segment depression or downsloping depression
of 1 mm or more in recovery were particularly use-
ful markers in these patients for diagnosis of any
coronary disease (likelihood ratio 3.4, sensitivity 67
percent, specificity 80 percent).
Factors that
preclude or interfere with proper interpretation of
ECG are listed in Table 3.
In a recently published study, after 23 years of fol-
low up, patients with frequent ventricular ectopy (a
run of 2 or more consecutive premature ventricular
contractions (PVC) making up more than 10% of
all PVCs on any 30 seconds ECG) had an increased
risk of death from cardiovascular causes by a fac-
tor of 2.5 times, similar to that observed in patients
who had a positive ischemic response to exercise.
Frequent PVCs at rest or during recovery were not
associated with an increase in cardiovascular mortal-
ity in this study, but in another study a stronger as-
sociation between ventricular ectopy during recovery
and increased 5-year mortality was noted.
Exercise-induced right bundle branch block
(RBBB) or left bundle branch block (LBBB) is usu-
ally considered nonspecific unless it is associated
with evidence of ischemia, i.e. angina, and then it
is strongly suggestive of ischemia. Causes for a false
positive test include left ventricular hyprtrophy
(LVH), which is associated with decreased exercise
testing specificity, but sensitivity is unaffected.
Digitalis causes exercise-induced ST depression in
25% to 40% of normal subjects.
Other diseases
that might cause a false positive test include mitral
or aortic valve dysfunction or mitral valve prolapse,
pulmonary hypertension, pericardial constriction,
hypokalemia, glucose ingestion prior to the test and
Figure 3. Down-sloping ST depression.
Figure 2. Horizontal ST depression.
Figure 1. Slowly up-sloping ST
in females during reproductive
Causes of false negative test
include use of β-blockers, which
may reduce the diagnostic or
prognostic value of exercise test-
ing because of inadequate heart
rate response, but the decision to
remove a patient from β-blocker
therapy for exercise testing should
be made on an individual basis
and should be done carefully to
avoid a potential hemodynamic
rebound effect, which can lead
to accelerated angina or hyperten-
Acute administration of
nitrates can attenuate the angina
and ST depression associated
with myocardial ischemia. Atrial
repolarization waves are opposite
in direction to P waves and may
extend into the ST segment and T
wave. Exaggerated atrial repolar-
ization waves during exercise can
cause downsloping ST depression
in the absence of ischemia.
e final Interpretation of the ECG is positive if
the ST criteria are met at any heart rate, and there
are no factors to preclude appropriate interpretation
of the test. e interpretation is negative if no sig-
nificant ST changes are noticed. e test is nondi-
Ann Saudi Med 26(1) January-February 2006
agnostic if the patient fails to achieve 85% of the
MPHR and the test was negative. e results are
indeterminate if the patient has baseline LBBB, a
paced rhytm, LVH with repolarization changes and/
or is on digoxin therapy. Patients with an abnormal
exercise ECG, but a normal perfusion scan have a
low risk for future cardiac events (<1%).
Exercise testing in women
Numerous reports have demonstrated a lower di-
agnostic accuracy for exercise electrocardiography
in women, in particular the occurrence of 1 mm of
ST segment depression. e average sensitivity and
specificity for the exercise electrocardiogram are 61%
and 69%.
e increased age of presentation by
women, coincident with functional impairment, is
associated with lower exercise capacity and an in-
ability to attain maximal stress. Additional critical
factors that have been reported to affect test accuracy
in women include resting ST-T wave changes in hy-
pertensive women and lower electrocardiographic
voltage and hormonal factors. For the premenopaus-
al woman, endogenous estrogen has a digoxin-like
effect that may precipitate ST segment depression,
resulting in a false positive test. Physicians who test
pre-menopausal women with chest pain or estab-
lished coronary disease should caution the use of
exercise stress testing in a womans mid-cycle where
estrogen levels are highest. Reports have noted a re-
duced frequency of ischemic episodes and chest pain
during this phase of the menstrual cycle. e accu-
racy of the exercise electrocardiogram in women is
highly variable and is influenced by multiple factors,
including exercise capacity and hormonal status. e
current American College of Cardiology/American
Heart Association (ACC/AHA) guidelines
exercise testing recommend this test as a first-line
test for those with a normal resting 12-lead ECG
and for those capable of performing maximal stress.
Although maximal stress may be defined by achiev-
ing 85% of predicted maximal heart rate, care should
be taken when interpreting a womans heart rate re-
sponse. For deconditioned patients, a hyperexagger-
ated response to physical work may result in marked
increases in heart rate. us, the test should be con-
tinued until maximal symptom-limited exercise ca-
pacity. Women incapable of performing a minimum
of 5 METS of exercise should be considered candi-
dates for myocardial perfusion imaging with phar-
macologic stress.
Women with diabetes are a special population
worthy of mention. ey are at an increased risk for
premature atherosclerosis and at significant risk for
myocardial infarction and cardiac death. e unique
pathophysiology of diabetes mellitus makes tradi-
tional symptoms less reliable and diagnosis of CAD
more challenging. e ECG is often a less reliable
indicator of significant CAD in the diabetic patient.
Myocardial perfusion imaging has been shown to be
accurate in the risk assessment and prediction of fu-
ture cardiac events in the diabetic woman.
Stress testing following myocardial infarc-
tion (MI)
Exercise stress testing is an invaluable tool for risk
stratification post-MI. In the early days post MI
(days 3-7), a low level stress test limited to 5 METS,
Table 3. Factors that preclude interpretation of exercise stress testing results.
• Left bundle branch block
• Left venticular hypertrophy with repolarization changes
• Digoxin therapy
• Right bundle branch block, cannot interpret leads V1-V3
Marked ST abnormalities at baseline with ST depression > 1 mm in at least two
• Paced ventricular rhythm
• Preexcitation syndrome (Wolff-Parkinson-White)
Table 2. Indications for early termination of exercise stress testing
• Hypotension, with SBP drop > 10 mmHg
• Ventricular or Supraventricular arrhythmias other than PVC’s or PACs
• Severe Hypertension, SBP >250 or DBP >120 mmHg
ST elevation (> 1mm in leads without Q waves), if transient, often indicate severe
proximal coronary stenosis and ominous prognosis
• Angina with dynamic ST changes
• Excessive ST Depression, > 2 mm horizontal or downsloping
• Signs of poor perfusion, i.e. pallor or cyanosis
• Achieving 100% of MPHR
High-risk criteria:
• Hypotension with systolic BP drop > 20 mm Hg
• Early positivity, within the first or second stage of the Bruce protocol
• Late recovery
• Diffuse ST-T changes
• More than 2 mm ST depression in multiple leads
• ST elevation
Ann Saudi Med 26(1) January-February 2006
75% of MPHR or 60% of MPHR on β−blockers, is
very helpful in patients who were treated conserva-
tively with no revascularization to assess for ischemia
at low workload, arrhythmias, to start cardiac reha-
bilitation and gaining self confidence. Late post-MI
(4-6 weeks), symptom limited stress testing is usu-
ally performed to assess revascularization, medical
therapy or need for any further intervetions.
EKG interpretation with pharmacologic
stress testing
e same criteria in exercise stress testing applies,
but the sensitivity of an adenosine and dipyridam-
ole pharmacologic stress EKG is much lower than
exercise stress testing (30% vs. 65% respectively).
However, specificity (95% vs. 85% respectively) and
PPV (90%) is much higher than exercise stress test-
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e finding of ischemic ECG changes with normal
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sociated with a higher subsequent cardiac event rate
than is customarily associated with normal images.
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had a sensitivity, specificity, PPV, and NPV of 52%,
64%, 72%, and 41%, respectively.
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nosing, risk stratifying or assessing cardiac patients
provided appropriate patient selection is used to en-
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... A full exercise test should be delayed for 4-6 weeks after myocardial infarction. 1 Complications of stress electrocardiography are rare. Serious complications (myocardial infarction, sustained ventricular arrhythmia, and death) occur in one out of 10,000 patients. ...
... Indications for discontinuation of the test1,14,15 Hypotension with systolic blood pressure drop >20 mm Hg (high-risk criteria) or systolic blood pressure drop >10 mm Hg. Malignant disorders of rhythm, ventricular or supraventricular origin. ...
Full-text available
Aim: To point out the importance of stress electrocardiography and to present the indications, contraindications, as well as reasons for test termination with reference to the interpretation of the findings. Background: Despite the development of modern cardiology and the availability of methods for the visualization of coronary artery disease (CAD), stress electrocardiography still has a role in clinical practice. Review results: It is a safe, affordable, and cheap test for the evaluation of CAD, with clear indications, contraindications, and a clearly defined population for which it is intended. Conclusion: It is imperative to correlate findings of stress electrocardiography with clinical symptoms, comorbidities, positive family history, and life habits, as well as pharmacological therapy of the patient. Clinical significance: Stress electrocardiography should be a part of the daily work of cardiologists. Keywords: Electrocardiography, Heart, Ischemia, Prevention.
... Noninvasive diagnostic testing (either exercise or pharmacological) is preferred and plays an important role in the diagnosis of cardiovascular disorders [2]. In addition to providing predictive value [2], the exercise stress test is inexpensive, widely accessible, and reasonably safe [3]. In this case report, we highlight the case of a patient who experienced Takotsubo syndrome/cardiomyopathy (TTS) during an exercise stress echocardiography. ...
Noninvasive stress testing is routinely indicated and preferable in the diagnosis of coronary artery disease. We present the case of a patient who developed Takotsubo syndrome/cardiomyopathy (TTS) as a result of an exercise stress echocardiography, as well as a literature review of comparable cases. An abnormal stress test necessitated coronary angiography, which revealed nonobstructive coronaries with apical left ventricular ballooning and a decreased ejection fraction (EF), both of which are concerning for TTS. The patient was medically managed with metoprolol and lisinopril, with improvement in the EF on the follow-up echocardiogram.
... The modified Bruce protocol [22] was applied. 12-lead ECG, heart rate, and blood pressure were closely monitored, symptoms constantly evaluated, and parameters such as maximal rate pressure product and metabolic equivalents (METs) of estimated exercise capacity systematically reported [22,23]. ...
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Background. Exercise stress test (EST) has been scarcely investigated in patients with arrhythmic myocarditis. Objectives. To report the results of EST late after myocarditis with arrhythmic vs. nonarrhythmic presentation. Methods. We enrolled consecutive adult patients with EST performed at least six months after acute myocarditis was diagnosed using gold-standard techniques. Patients with ventricular arrhythmia (VA) at presentation were compared with the nonarrhythmic group. Adverse events occurring during follow-up after EST included cardiac death, disease-related rehospitalization, malignant VA, and proven active myocarditis. Results. The study cohort was composed of 128 patients (age 41 ± 9 y, 70% males) undergoing EST after myocarditis. Of them, 64 (50%) had arrhythmic presentation. EST was performed after 15 ± 4 months from initial diagnosis, and was conducted on betablockers in 75 cases (59%). During EST, VA were more common in the arrhythmic group (43 vs. 4, p < 0.001), whereas signs and symptoms of ischemia were more prevalent in the nonarrhythmic one (6 vs. 1, p = 0.115). By 58-month mean follow-up, 52 patients (41%) experienced adverse events, with a greater prevalence among arrhythmic patients (39 vs. 13, p < 0.001). As documented both in the arrhythmic and nonarrhythmic subgroups, patients had greater prevalence of adverse events following a positive EST (40/54 vs. 12/74 with negative EST, p < 0.001). Electrocardiographic features of VA during EST correlated with the subsequent inflammatory restaging of myocarditis. Nonarrhythmic patients with uneventful EST both on- and off-treatment were free from subsequent adverse events. Conclusions. Late after the arrhythmic presentation of myocarditis, EST was frequently associated with recurrent VA. In both arrhythmic and nonarrhythmic myocarditis, EST abnormalities correlated with subsequent adverse outcomes.
... According to the 2019 European Society of Cardiology (ESC) guideline, an exercise electrocardiogram (ECG) is a valuable tool for confirming the diagnosis of coronary artery disease (CAD) in suspected patients, but it is not indicated in the asymptomatic population without suspicion toward CAD (1). The interpretation of this test to detect CAD is commonly known to rely substantially on the development of ST-segment deviation (2). However, premature ventricular complexes (PVCs), another ECG sign, can also develop during exercise ECG (3)(4)(5). ...
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Background Recent investigations suggest that premature ventricular complexes (PVCs) during an exercise test are associated with an elevated risk of mortality in asymptomatic individuals. However, given the small number of studies included, the association between these two entities in the asymptomatic population remains obscure. Our aim was to evaluate this matter. Methods A comprehensive literature search was conducted utilizing several online databases up to April 2022. The study comprised cohort studies examining the relationship between exercise-induced premature ventricular complexes (EI-PVCs) and all-cause mortality (ACM) as well as cardiovascular mortality (CVM) in asymptomatic populations. To provide diagnostic values across the statistically significant parameters, we additionally calculated sensitivity, specificity, and area under the curve (AUC). Results A total of 13 studies consisting of 82,161 patients with a mean age of 49.3 years were included. EI-PVCs were linked to an increased risk of ACM (risk ratio (RR) = 1.30 (95% confidence interval (CI) = 1.18–1.42); p < 0.001; I ² = 59.6%, p -heterogeneity < 0.001) and CVM (RR = 1.67 (95% CI = 1.40–1.99); p < 0.001; I ² = 7.5%, p -heterogeneity = 0.373). Subgroup analysis based on the frequency of PVCs revealed that frequent PVCs were similarly related to a higher risk of ACM and CVM, but not infrequent PVCs. Moreover, diagnostic test accuracy meta-analysis showed that recovery phase EI-PVCs have a higher overall specificity than exercise phase EI-PVCs regarding our outcomes of interest. Conclusion EI-PVCs are correlated with a higher risk of ACM and CVM. When compared to the exercise phase, the specificity of PVCs generated during the recovery period in predicting interest outcomes is higher. As a result, we propose that the exercise ECG be utilized on a regular basis in middle-aged asymptomatic individuals to measure the frequency of PVCs and stratify the risk of mortality. Systematic review registration [ ], identifier [CRD42022328852].
... The following data were collected or calculated based on the electronic health record of Sheba Medical Center in the year in which the index colonoscopy was performed: For each subject, we extracted the metabolic equivalents (MET) scoring achieved during a treadmill stress test by the Bruce protocol, as an indicator for exercise capacity [18]. We also defined a categorical variable "METs score ≥ 10" representing METs score ≥ 10 during stress test, indicating a lower probability for ischemic heart disease [19]. ...
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Background The association between diverticular disease and atherosclerotic cardiovascular disease (ASCVD) has been demonstrated previously, mainly in symptomatic subjects. Aims To evaluate 10 years cardiovascular risk, exercise performance and association to ASCVD among subjects with asymptomatic diverticulosis. Methods A retrospective cross-sectional cohort of self-referred participants in a medical screening program, who underwent a screening colonoscopy. Demographics, clinical and laboratory variables, ASCVD score, and metabolic equivalents (METs) during treadmill stress test were compared between subjects with and without diverticulosis as diagnosed on screening colonoscopy. Results 4586 participants underwent screening colonoscopy; 799 (17.4%) had diverticulosis. Among 50–69 yo participants, diverticulosis subjects had a higher ASCVD score compared to non-diverticulosis subjects. Exercise performance was comparable between the groups, across all age groups. Using logistic regression analysis, advanced age group (50–59 yo Adjusted odds ratio (AOR) [95% confidence interval (CI)] 2.57 (1.52–4.34), p < 0.001; 60–69 yo, AOR 2.87 (2.09–3.95), p < 0.001; ≥ 70 yo AOR 4.81 (3.23–7.15), p < 0.001; compared to < 50 yo age group), smoking [AOR 1.27 (1.05–1.55), p = 0.016], HTN [AOR 1.27 (1.03–1.56), p = 0.022], obesity [AOR 1.36 (1.06–1.74), p = 0.014] and male sex [AOR 1.29 (1.02–1.64), p = 0.036] were associated with diverticular detection during screening colonoscopy. Among males, achieving METs score ≥ 10 was inversely associated with diverticular detection during screening colonoscopy [AOR 0.64 (0.43–0.95), p = 0.027]. Conclusions Ten years probability for ASCVD estimated by the ASCVD score is higher among subjects with asymptomatic diverticulosis compared to subjects without diverticulosis. Improved exercise performance is demonstrated for the first time to correlate with decreased probability for diverticular disease in screening colonoscopy.
... Cardiac stress testing tracks and identifies CVD-related risks in asymptomatic patients with 85% specificity and 60-70% sensitivity [17]. The electrocardiogram stress test effectively determines ischemic changes in asymptomatic CVD patients. ...
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The cardiac stress testing, carotid duplex, coronary artery calcium (CAC) scoring, myocardial perfusion imaging, coronary angiography, C-reactive protein (CRP), glycated hemoglobin (HbA1C), total serum cholesterol, duplex ultrasonography, digital subtraction angiography, magnetic resonance angiography (MRA), computed tomography angiography (CTA), digital subtraction angiography, and ankle-brachial index (ABI) independently predict the risks and prognostic outcomes in asymptomatic cardiovascular disease (CVD) patients. The peripheral artery disease (PAD) screening guides the diagnosis, management, and prognosis of hemodynamically significant arterial stenosis, calcification, and malignant hypertension in patients with CVD without symptoms. The 79% sensitivity and 96% specificity of ABI screening, 90% sensitivity and 97% specificity of MRA, and 95% sensitivity and 50% specificity of CTA for tracking arterial occlusion indicate the high prognostic value of these tests in the setting of CVD. The 85% specificity and 60-70% sensitivity of cardiac stress testing substantiate its suitability to determine asymptomatic CVD prognosis related to myocardial ischemia, heart failure, multivessel disease, and unstable angina. The carotid duplex ultrasound potentially identifies long-term mortality, stroke, atherosclerosis, plaque instability, and angiographic stenosis among asymptomatic CVD patients with 94% specificity and 90% sensitivity. The CAC scoring has a positive predictive value (PPV) of 45.7% for identifying aortic valve calcium and PPV of 79.3% for tracking thoracic artery calcium. The medical literature provides substantial evidence concerning the validity, reliability, and prognostic value of cardiovascular testing for asymptomatic patients. Future studies are needed to undertake detailed assessments of benefits versus adverse outcomes associated with the prospective scaling (of cardiovascular testing) across asymptomatic CVD patients.
INTRODUCTION: The exercise electrocardiogram (ExECG), or stress test, is a widely used screening tool in occupational medicine designed to detect occult coronary artery disease, and assess performance capacity and cardiovascular fitness. In some guidelines, it is recommended for high-risk occupations in which occult disease could possibly endanger public safety. In aviation medicine, however, there is an ongoing debate on the use and periodicity of ExECG for screening of aircrew.METHOD: In the German Armed Forces, aircrew applicants and active-duty aircrew undergo screening ExECG. We analyzed 7646 applicant ExECGs (5871 from pilot and 1775 from nonpilot applicants) and 17,131 ExECGs from 3817 active-duty pilots. All were performed at the German Air Force Centre of Aerospace Medicine (GAFCAM) and analyzed for ECG abnormalities, performance capacity, blood pressure, and heart rate response.RESULTS: Only 15/5871 (0.2%) of pilot applicants required further investigation and none were ultimately disqualified for aircrew duties due to their ExECG results. Of the nonpilot applicants, 22/1775 (1.2%) required further diagnostic work-up due to their ExECG findings, with only 1 ultimately disqualified. From active-duty pilots, 84/17,131 (0.5%) ExECGs revealed findings requiring further investigation, with only 2 pilots ultimately disqualified from flying duties.DISCUSSION: The extremely low yield of ExECG findings requiring further evaluation and/or disqualification for aircrew duties suggest its use is questionable and not cost-effective as a screening tool in this cohort. It may be enough to perform ExECG on clinical indication alone.Guettler N, Nicol ED, Sammito S. Exercise ECG for screening in military aircrew. Aerosp Med Hum Perform. 2022; 93(9):666-672.
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Excess epicardial adiposity, within a state of obesity and metabolic syndrome, is emerging as an important risk factor for the development of cardiovascular diseases (CVDs). Accordingly, increased epicardial fat thickness (EFT) implicates the exacerbation of pathological mechanisms involving oxidative stress and inflammation within the heart, which may accelerate the development of CVDs. This explains increased interest in targeting EFT reduction to attenuate the detrimental effects of oxidative stress and inflammation within the setting of metabolic syndrome. Here, we critically discuss clinical and preclinical evidence on the impact of physical exercise on EFT in correlation with reduced CVD risk within a setting of metabolic disease. This review also brings a unique perspective on the implications of oxidative stress and inflammation as major pathological consequences that link increased EFT to accelerated CVD risk in conditions of metabolic disease.
In an era where cardiovascular disease continues to increase in prevalence, chest pain is a commonly encountered complaint in the outpatient setting. Clinicians are often tasked with the challenge of selecting the most appropriate screening tool in the evaluation of a patient with suspected coronary artery disease. With proper consideration of indications and contraindications, exercise electrocardiogram (ECG) stress testing is an accessible, cost-conscious, and validated outpatient diagnostic modality for predicting coronary artery disease.
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The diagnosis of coronary-artery disease has become increasingly complex. Many different results, obtained from tests with substantial imperfections, must be integrated into a diagnostic conclusion about the probability of disease in a given patient. To approach this problem in a practical manner, we reviewed the literature to estimate the pretest likelihood of disease (defined by age, sex and symptoms) and the sensitivity and specificity of four diagnostic tests: stress electrocardiography, cardiokymography, thallium scintigraphy and cardiac fluoroscopy. With this information, test results can be analyzed by use of Bayes' theorem of conditional probability. This approach has several advantages. It pools the diagnostic experience of many physicians ans integrates fundamental pretest clinical descriptors with many varying test results to summarize reproducibly and meaningfully the probability of angiographic coronary-artery disease. This approach also aids, but does not replace, the physician's judgment and may assit in decisions on cost effectiveness of tests.
A 6 year follow-up study of 438 patients who underwent maximal treadmill stress testing revealed the following annual incidence rate of coronary events (death, myocardial infarction or onset or progression of angina pectoris): 13 percent in 84 subjects whose stress test produced 2 mm downsloping S-T segment depression, 9 percent in 230 subjects with 2 mm horizontal S-T depression and 9 percent in 124 subjects who had an upsloping S-T segment with 2 mm S-T depression measured 0.08 second from the J point.
Factors causing the false positive stress test and the ability of the computer to improve test classification were studied in 95 patients with a positive stress test and normal coronary angiograms and 125 patients with a true positive stress test. Multivariate analysis revealed that in men the following clinical findings other than S-T depression were useful in correct stress test classification: (1) maximal heart rate, (2) maximal systolic blood pressure, (3) contour of S-T segment, (4) age, (5) history of chest pain, (6) T waves in resting record, (7) chest pain during test, (8) S-T and T changes with hyperventilation, (9) resting electrocardiogram, (10) time of onset of S-T depression, and (11) increase in P wave negativity in lead V1 with exercise. These variables, presented in order of importance, had a different ranking in women.
This study presents the results of maximal treadmill testing and cardiac catheterization in 40 asymptomatic and apparently healthy men with acquired right bundle-branch block. Eight of the men had significant angiographic coronary artery disease, and six of the eight only had single-vessel disease. The 40 men had normal maximal oxygen consumptions, normal maximal heart rates, and normal maximal blood pressure responses; none of the men had abnormal ST-segment changes in response to maximal treadmill testing. Thus, the sensitivity of exercise testing for coronary artery disease in men with right bundle branch block is uncertain. However, the apparently high specificity of exercise testing demonstrated by this study necessitates further evaluation for coronary artery disease in men with right bundle branch block who develop abnormal ST-segment depression in response to exercise testing.
Resting ST segment depression has been identified as a marker for adverse cardiac events in patients with and without known coronary artery disease. To correlate this with exercise testing, coronary angiography, and how it impacts on long-term prognosis, a retrospective study was performed on 476 patients, of whom 223 had no clinical or electrocardiographic evidence of prior myocardial infarction while 253 were survivors of an infarction. All patients performed a standard exercise test and underwent diagnostic coronary angiography within an average of 32 days of their exercise test (range 0 to 90 days). Exclusions were women, those with left bundle branch block, left ventricular hypertrophy, use of digoxin, previous revascularization procedures, or significant valvular or congenital heart disease. Long-term follow-up was carried out for an average of 45 months (± 17). Of the patients without prior infarction, 23 (10%) had persistent resting ST segment depression, and of those with a prior history of infarction, 37 (15%) also had resting ST segment depression. Patients with resting ST segment depression and no prior myocardial infarction had a higher prevalence of severe coronary disease (three-vessel and/or left main) (30%) than those without resting ST segment depression (16%) (95% confidence interval [Cl] for observed difference −5.0% to 33.9%, p = 0.12. The criterion of ≥ 2 mm of additional exercise-induced ST segment depression was a particularly useful marker in these patients for the diagnosis of any coronary disease (likelihood ratio 3.35, 95% Cl 0.56 to 19.93, p = 0.06). Patients with resting ST segment depression and a prior myocardial infarction had a 2.5 times higher prevalence of severe coronary artery disease compared with patients without resting ST segment depression (43% versus 17% prevalence, respectively, 95% Cl for observed difference 9.38% to 42.8%, p < 0.001) and also had larger left ventricles postinfarction (left ventricular end-diastolic volume index 102 ml/m2 compared with 96 ml/m2, p < 0.001). To identify severe coronary artery disease in post-infarction patients with persistent resting ST segment depression, the criteria of ⩾2 mm of additional exercise-induced ST segment depression (likelihood ratio 2.96, 95% Cl 1.12 to 7.92, p = 0.02) or having the additional exercise-induced ST segment depression persist ⩾ 4 minutes into recovery (likelihood ratio 3.62, 95% Cl 1.41 to 9.27, p = 0.002) were better markers than the standard criterion of ⩾1 mm of additional ST segment depression (likelihood ratio 1.67, 95% Cl 1.07 to 2.61, p = 0.02). Receiver operating characteristic curve analysis revealed that additional exercise-induced ST segment depression continued to discriminate between those with or those without any, or severe, coronary disease despite having baseline ST segment depression at rest (p ⩽ 0.005). After a cumulative follow-up of 4.4 years, patients with resting ST segment depression, with (p = 0.079) or without (p = 0.009) prior myocardial infarction, had a lower infarct-free survival rate than those without it. Resting ST segment depression (not due to left ventricular hypertrophy, conduction defects, or drug effect) is a marker for a higher prevalence of severe coronary artery disease with a poor prognosis, and standard exercise testing continues to be diagnostically useful in these patients.
This study presents the results of maximal treadmill testing and coronary angiography in 31 asymptomatic USAF aircrewmen with acquired left bundle branch block. There were two subgroups: 26 men with normal coronary angiography and five men with significant angiographic coronary angiography and five men with significant angiographic coronary artery disease. The mean amount of maximal ST-segment depression induced by treadmill exercise was −0.5 mv. for both groups and the range in the normal subgroup was −0.3 to −1.0 mv. No significant differences were found between the groups. We concluded that apparently healthy, asymptomatic men with acquired left bundle branch block can have considerable ST-segment depression in response to maximal treadmill testing and that their ST-segment response cannot be used to make diagnostic decisions about them.
A review of 6040 consecutive exercise tests yielded 106 patients without previous myocardial infarction (MI) who had exercise-induced ST elevation (greater than or equal to 0.5 mm in a 15-lead ECG system). In 46, ST elevation was correlated with left ventriculography and coronary angiography. Coronary artery disease (CAD) (greater than or equal to 70% narrowing) was detected in 40 of 46 patients: 12 patients had one-vessel disease, 13 had two-vessel disease, and 15 had three-vessel disease. Resting ventriculograms were normal in 36 of 40 patients. Of 21 patients with anterior (V1-V3) ST elevation, 86% had a left anterior descending (LAD) obstruction and 78% had obstruction proximal to the first diagonal branch. LAD disease occurred significantly more frequently than right and circumflex CAD. There was no anatomic correlation of three persons with lateral (leads V4--6, I or aVL) or 27 patients with inferior-posterior (leads II, III, aVF, Y or Z) exercise-induced ST elevation. Therefore, exercise-induced ST elevation is strongly correlated with CAD but not resting wall motion abnormalities. Further, anterior exercise-induced ST elevation in patients without a previous MI often predicts a significant proximal LAD obstruction.
The effects of propranolol, digoxin and combination therapy (/D) on the resting and exercise ECG were studied in ten normal subjects and 20 patients with coronary artery disease (CAD) given a sequence of oral placebo, propranolol, P/D, digoxin and placebo, for two week periods. Digoxin produced a significant decrease in T-wave amplitude and often resulted in ST segment depression in the resting ECG. Propranolol, digoxin, and P/D tended to decrease the QTc interval and prolong the PR interval. However, CAD patients were more sensitive to PR prolongation than normals while receiving propranolol or digoxin alone. Propranolol therapy did not significantly affect the ST segment of the exercise ECG in the normal subjects or the CAD patients without an ischemic control exercise ECG. By contrast, 50 per cent of the normal subjects developed "false-positive" ischemic ST segment responses to exercise while receiving digoxin of P/D and three of eight CAD patients without ischemic control exercise ST segments had a similar response to digoxin or P/D. In 12 CAD patients with ischemic control exercise ST segments, propranolol did not affect the amount of ST segment depression at the onset of angina or the maximum amount of ST segment depression. Digoxin or P/D both uniformly increased the maximum amount of ST segment depression which was greater with digoxin than P/D. However, the maximum heart rate on P/D was significantly reduced as compared to that on digoxin. It is concluded that (1) CAD patients are more sensitive to propranolol or digoxin-induced AV block than normals, (2) propranolol does not change the magnitude of ischemic exercise ST segment depression, (3) digoxin increases ischemic exercise ST segment depression and results in a high incidence of false-positive exercise tests, and (4) the addition of propranolol to digoxin attenuates the effects of digoxin on the exercise ST segment.
In 1214 symptomatic medically treated patients with coronary artery disease, 57 noninvasive baseline clinical characteristics and 24 catheterization descriptors were analyzed by a multivariable analysis technique to determine the characteristics that were independent predictors of survival and, in particular, to determine whether noninvasive characteristics contributed prognostic information in addition to catheterization findings. When the noninvasive characteristics were analyzed, 31 characteristics were significant (p<0.05) univariate predictors of survival, but only 12 contained significant independent prognostic information. Five- and 7-year survival rates in 197 patients who had none of the independently significant noninvasive characteristics were both 90%. Nineteen variables were significant when the catheterization descriptors were analyzed individually. Only seven were independently significant when they were analyzed jointly. When all 81 baseline characteristics were analyzed jointly, seven noninvasive characteristics (history of peripheral vascular disease, New York Heart Association class IV heart failure, nonspecific intraventricular conduction defect, progressive chest pain, nocturnal pain, premature ventricular complexes on the resting ECG, and left bundle branch block) and six invasive characteristics (left-main stenosis, arteriovenous oxygen difference, number of diseased vessels, abnormal left ventricular contraction, left ventricular end-diastolic pressure and anterior asynergy) were independently significant. Different survival rates may occur in subsets that are uniform with respect to only one or two important characteristics (e.g., coronary anatomy and ventricular function) because of differences in other important baseline characteristics. Both noninvasive and invasive characteristics must be taken into account to define prognosis in coronary disease fully.