Can ECG Rule Out ACS if Performed While the Patient Is Having Chest Pain?

Mark: This is a prospective, observational study to determine if negative electrocardiography (ECG) performed while the patient is having chest pain can reliably rule out coronary disease. Eligible participants presented to the emergency department with chest pain and had normal initial ECG. Eligibility criteria also included age older than 25 years, two negative troponins over six hours, and admission for a cardiac workup. Patients meeting inclusion criteria were noted to be either pain free or having pain during the initial ECG. They were then followed to see if the incidence of acute coronary syndrome (ACS) differed in those with and without pain during ECG. In other words, does negative ECG performed in patients with pain reliably rule out ACS? A total of 387 (22 percent) of the patients with chest pain met the inclusion criteria. The mean age was 56 years, and 51 percent were men. Overall, 126 patients (33 percent) did not have chest pain during ECG and 261 patients (67 percent) did have chest pain during ECG. ACS was ultimately diagnosed in 67 patients based on a positive stress test, a positive troponin test, or coronary artery stenosis of greater than 70 percent. Sixteen percent of the group with negative ECG performed during chest pain ultimately proved to have ACS, versus 20 percent of those with positive ECG performed while not having chest pain (odds ratio = 0.77; 95% confidence interval = 0.45 to 1.33; P = .4). Importantly, 31 percent of admitted patients did not have a confirmatory test.