Robert J. Newman, MD
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Coronary artery disease (CAD) is the leading cause of death in the United States for both men and women. Chest pain is a common
complaint in primary care and may be the presenting symptom of CAD. Exercise stress testing (EST) is helpful in evaluating
chest pain in selected patients and is a cost-effective strategy for triaging patients with chest pain in the primary care
setting. Consideration should be given to adding this capability to the patient-centered medical home.
Only 13 percent of family physicians currently perform EST. Barriers cited include lack of physician training and the high
cost of EST equipment.1 The first barrier can be overcome by adding EST training during primary care residencies with a standardized curriculum.
High-quality courses are available through the National Procedures Institute and the American Academy of Family Physicians
Annual Scientific Assembly. Cost should not be a concern because the cost of the equipment is reasonable and, when combined
with a Holter-monitoring system, can quickly pay for itself.
INDICATIONS
There are many indications for EST in primary care. Most common and most important is the evaluation of patients with an intermediate
pretest probability of CAD, such as middle-aged and older persons with atypical chest pain. This is a class I indication (highly
recommended) by the American College of Cardiology (ACC)/American Heart Association (AHA) guidelines.2 Other indications include follow-up testing after a CAD diagnosis, pre-exercise screening in asymptomatic patients with
multiple cardiac risk factors (especially diabetes), evaluation of dysrhythmias, and determining functional capacity prior
to writing an exercise prescription.2 There is insufficient evidence to recommend EST as a routine screening modality in asymptomatic adults, although it is often
used for prognostic information in asymptomatic men older than 45 years and women older than 55 with multiple cardiac risk
factors, including hypertension, hypercholesterolemia, diabetes, smoking, and a family history of premature CAD.3 For these individuals, EST has been recommended as an evaluative tool prior to embarking on vigorous competitive sports
activity.4Establishing the pretest probability of CAD is crucial before performing EST. Patient age, sex, and description of the chest
pain are the best determinants, and patients can be stratified into low, intermediate, and high-risk pretest probability.2,5 Each cardiac risk factor increases the pretest probability of CAD. Since the sensitivity of EST in determining CAD is only
67 percent, patients with high pretest probability may need EST testing with Sestamibi (nuclear scan) imaging with its higher
sensitivity of 83 percent. In patients with low-to-intermediate pretest probability, the predictive value of a negative test
can be as high as 99.3 percent.1 This is the population that is usually studied in the primary care office in contrast to cardiology practices, where the
pretest probability is much higher.
CONTRAINDICATIONS
Contraindications to EST include acute myocardial infarction, unstable angina, pulmonary embolism, severe aortic stenosis,
decompensated congestive heart failure, acute medical illness, hypertrophic obstructive cardiomyopathy, uncontrolled hypertension,
dissecting aneurysm, and acute myocarditis or pericarditis.6 Careful selection of patients is critical. Those with left bundle-branch block, patients taking digoxin, patients with pacemakers,
and those with significant ST segment abnormalities at baseline should be considered for Sestamibi nuclear imaging EST or
stress echocardiography. Those unable to walk two blocks or two flights of stairs should have an adenosine or dobutamine Sestamibi
study done instead of EST without imaging.
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