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C HAP TE R 1 9 / Exercise Testing 421

traindications to exercise testing. 4,17 If the reason the patient was
DISPLAY 19-1 Contraindications to Exercise Testing referred for the test in unclear, it should be postponed until this is
clarified. The medical history should include any remote or recent
Absolute
medical problems, symptoms, medication use, and findings from
1. A recent change in the resting electrocardiogram sug- previous examinations and tests. Major CAD risk factors and
gesting infarction or other acute cardiac event signs and symptoms suggesting cardiopulmonary disease should
2. Recent complicated MI be identified. Physical activity patterns, vocational requirements,
3. Unstable angina and family history of cardiopulmonary and metabolic disorders
4. Uncontrolled ventricular arrhythmia should also be assessed. Identification of absolute contraindica-
5. Uncontrolled atrial arrhythmia that compromises car- tions (see Display 19-1) should result in cancellation of the test
diac function
6. Third-degree atrioventricular heart block without and referral of the patient to the primary physician for further
pacemaker medical management. Patients with relative contraindications
7. Acute congestive heart failure may be tested only after careful evaluation of the risk-to-benefit
8. Severe aortic stenosis ratio.
9. Suspected or known dissecting aneurysm Detailed verbal and written instructions, provided to the pa-
10. Active or suspected myocarditis or pericarditis tient in advance, should include a request that the patient refrain
11. Thrombophlebitis or intracardiac thrombi from ingesting food, alcohol, and caffeine or using tobacco prod-
12. Recent systemic or pulmonary embolus ucts within 3 hours of testing. Patients should be well rested and
13. Acute infections avoid vigorous activity the day of the test. Clothing should be
14. Significant emotional distress (psychosis)
comfortable and provide freedom of movement as well as allow
access for electrode and blood pressure cuff placement. Properly
Relative
fitting shoes with rubber soles should be worn to ensure good
1. Resting diastolic blood pressure 115 mm Hg or rest- traction, particularly if a treadmill is the mode of testing. A thor-
ing systolic blood pressure 200 mm Hg ough explanation of the potential risks and discomforts associated
2. Moderate valvular heart disease with exercise testing should be provided. Written informed con-
3. Known electrolyte abnormalities (hypokalemia, hypo-
magnesemia) sent has important ethical and legal implications and ensures the
4. Fixed-rate pacemaker patient knows and understands the purposes and risks associated
5. Frequent or complex ectopy with the exercise test. There is sufficient case law to suggest that
6. Ventricular aneurysm informed consent should always be obtained before beginning a
12
7. Uncontrolled metabolic disease (e.g., diabetes, thyro- test, although this issue has also been debated. A demonstration
toxicosis, or myxedema) of how to get on and off the testing apparatus should be given,
8. Chronic infectious disease (e.g., mononucleosis or what is expected of the patient should be described (reporting of
myxedema) symptoms, level of exertion, testing endpoints), and any questions
9. Neuromuscular, musculoskeletal, or rheumatoid disor- the patient has should be answered.
ders exacerbated by exercise
10. Advanced or complicated pregnancy Whether patients should remain on all cardiovascular medi-
cines for exercise testing has been the source of some debate.
Many commonly used drugs can influence hemodynamic and
Modified from Gibbons, R. J., Balady, G. J., Bricker, J. T., et al. (2002). ACC/AHA 4,17
2002 guideline update for exercise testing. A report of the ACC/AHA Task Force on electrocardiographic responses to exercise (Table 19-1), but re-
Practice Guidelines (Committee on Exercise Testing). Journal of the American College moving patients from their usual medicines can cause instability
of Cardiology,40, 1531–1540.
of symptoms, rhythm, blood pressure, and other problems. Re-
cent versions of the aforementioned exercise testing guidelines 4,8
or technician conducting the test should have a comprehensive
knowledge of the indications, contraindications, equipment, suggest that most patients can remain on their medical regimen
physiologic responses to exercise, and clinical condition of the pa- for testing without greatly compromising the diagnostic perform-
tient to optimize the information yield and conduct the test safely. ance of the test. Tapering -blockers over several days or discon-
A joint statement by the American College of Physicians, the tinuing antianginal medications for a particular number of hours
ACC, and the AHA regarding clinical competence in exercise test- before testing should be reserved for particular patients in whom
ing outlined the cognitive skills needed to perform exercise test- diagnostic sensitivity is paramount, and the tapering process
ing. 11 These include knowledge of indications and contraindica- should be carefully supervised by a physician.
tions to testing, basic exercise physiology, principles of
interpretation, and emergency procedures. The committee sug- Preparation for Electrocardiogram
gested that at least 50 procedures were required during training to
achieve these skills. ACSM certification 8,10 is widely used to es- Diagnostically, the electrocardiographic response is the corner-
tablish competency for technicians, nurses, or physiologists who stone of the clinical exercise test. Thus, reliable test interpretation
oversee exercise testing and training. and patient safety mandate a high-quality exercise electrocardio-
gram. Proper skin preparation and precise electrode placement are
critical to obtaining a high-quality electrocardiogram tracing. The
goal of skin preparation is to decrease resistance at the skin–
PRETEST CONSIDERATIONS electrode interface and thus improve the signal-to-noise ratio. Af-
ter removing hair from the general areas of placement, each site
Before an exercise test, all patients should undergo a complete should be vigorously rubbed with an alcohol pad to remove skin
medical evaluation and a physical examination to identify con- oil. To further reduce resistance, the skin should be lightly