The EKG does have some role in diagnosis, helping to determine whether the chest pain is caused by a heart problem, Timmis noted.
"The study is a reminder of the importance of taking a detailed history and making a thorough physical examination, and that additional information from the EKG is helpful in some patients but does not predict risk in everyone," Dr. Beth Abramson, director of the Cardiac Prevention Centre at St. Michael's Hospital in Toronto, wrote in an accompanying journal editorial.
The study showed that the combination of an EKG and a stress test can be helpful because "an abnormal EKG and abnormal stress test independently predicted adverse events, such as death or acute coronary syndrome in the cohort study," Abramson wrote.
But some people with normal EKGs and normal stress tests in the study did have coronary events, "so the study cannot provide an answer about which approach should be used in patients with a normal EKG," she wrote. "These patients need to have their cardiac risk factors assessed regularly by their general practitioner and, if necessary, modified."
The study also showed that "the stress test and EKG are not foolproof indicators of risk," Abramson wrote. "However, even though these tests cannot predict all future events, they are a necessary extension of the physical examination in patients with suspected angina."
Timmis said, "We are looking for better tests to classify patients in terms of risk." Some newer methods show promise, "but all these tests need to be assessed not for their standalone value but for clinical value in these patients."
More details on EKGs are described by the U.S. Library of Medicine.
SOURCES: Adam Timmis, M.D., professor, clinical cardiology, London Chest Ho
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