Some chest pain patients may benefit from more evaluation

New research shows that almost 3 percent of patients who went to hospital emergency rooms with chest pain – but who weren’t initially diagnosed with heart problems – went on to have heart attacks or other heart-related events within a month.

The study, by Wake Forest University Baptist Medical Center researchers and colleagues from seven other medical centers, will be reported in the December issue of Annals of Emergency Medicine and is currently available on-line. “Not all chest pain is heart related and, unfortunately, some patients whose pain is diagnosed as non-heart related end up having heart attacks,” said Chadwick Miller, M.D., lead researcher, from Wake Forest Baptist. “We wanted to know how frequently this happens and what characteristics these patients have in common that could help physicians in the difficult task of evaluating chest pain.”

The researchers reviewed data from 15,608 patients who were evaluated for chest pain in nine hospital emergency departments between June 1999 and July 2001. All patients with a diagnosis of non-cardiac chest pain were contacted by phone, and researchers reviewed their hospital records to determine their outcome at 30 days. Other diagnoses included heart attack, low-risk chest pain, unstable angina and high-risk chest pain.

The analysis found that 2.8 percent of patients who were initially diagnosed with non-cardiac chest pain had definitive evidence of a heart attack, unstable angina, cardiac death or a procedure to re-open blocked heart vessels within a month after their diagnosis. Another 3.5 percent of the patients had possible evidence of an adverse heart event, but there was not enough information to say for sure.

Miller said these levels may seem relatively low, but would represent a significant level of death and illness on a nationwide scale.

There is no single, definitive test to diagnose heart attacks, making it difficult to evaluate chest pain patients, the researchers said. It is too costly to admit seemingly low-risk patients to the hospital for extensive testing. On the other hand, physicians do not want to miss a heart attack diagnosis.

Most doctors err on the side of caution, the researchers said. More than two-thirds of patients admitted to the hospital with chest pain are not having a heart attack. Physicians typically base treatment decisions on an initial impression from the patient’s history, physical exam and findings from an electrocardiogram. “This is a practical approach, but until this study, there was no information on the outcomes of patients with a diagnosis of non-cardiac chest pain,” said Miller.

Causes of non-cardiac chest pain can include stomach disorders, blood clots in the lungs, pneumonia, chest wall disorders, and anxiety.

The researchers found that patients who were diagnosed with non-cardiac chest pain and then had heart events were older (61 year versus 48 years) and more likely to be men (60 percent versus 39 percent) than the patients who did not have events. Other factors associated with adverse cardiac events were high cholesterol, diabetes, a history of heart vessel disease and a history of congestive heart failure, which is when the heart does not pump enough blood to meet the body’s demands. “When the doctor’s initial impression is non-cardiac chest pain, further evaluation should be considered if the patient has high-risk features such as a history of heart vessel disease, older age and high cholesterol,” said Miller.

The researchers said the findings could help improve care and reduce costs. “If we could use this new information to reduce the number of patients who have heart attacks after leaving the emergency department, quality will improve,” said Miller. “Furthermore, if physicians can safely identify a group of patients who do not require additional evaluation, health care spending will decrease.”