The Journal of Emergency Medicine released findings in January that showed exercise tolerance may be an important predictor of complications in patients presenting to Emergency Rooms with potential acute coronary syndromes. The researchers found a stronger association between poor exercise tolerance and myocardial infarction (MI) than five traditional cardiac risk factors (diabetes mellitus, hypertension, smoking hyperlipidemia, family history). Although they were hesitant to distinguish between a cause/effect relationship between exercise levels and heart disease, they did infer that, conceptually speaking, the study results most likely parallel the oxygen supply-demand insufficiencies that occur during positive cardiac stress tests. Similar to stress testing, the clinician’s subjective assessment of exercise tolerance precludes completely ruling out heart disease. The researchers do emphasize, however, that exercise tolerance “may be useful as an integral part of model for cardiac evaluation.”

Study Detail
A sample of 166 ER patients presenting with chest pain, dyspnea (shortness of breath), syncope (fainting) or epigastric pain underwent traditional cardiac evaluation and had their exercise tolerance estimated by attending physicians. Tolerance was estimate as excellent in 20%, good in 38%, bad in 30%, and very poor in 12%. The primary outcome, risk of MI or death, was reached in 9 patients. Of these, exercise tolerance was rated as excellent in one patient, good in one patient, bad in five patients, and very poor in two patients.

The secondary outcome, risk of MI or death associated with age, sex or the presence of any of the five traditional cardiac risk factors, demonstrated that patients with low exercise tolerance had an increased risk for MI compared with the risk associated with having any of the five traditional risk factors.

Questions to consider:

• How in-depth is your cardiovascular systems evaluation in terms of exercise or activity tolerance?
• Are you comfortable assessing a patient’s exertion history by simply “looking at the patient?”

For more information on this study please reference www.elsevier.com, search “JEM”, Volume 36, Issue 1.

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