Patients with acute myocardial infarction (MI) have longer duration of chest pain than those without MI. Patients with chest pain of short duration, less than 5 minutes, are unlikely to have an acute infarction and have a good prognosis at 30 days.

A single–center study showed that only 8.9% of the patients received a final diagnosis of acute MI, and these patients had a significantly longer duration of chest pain compared with the rest of the cohort (120 versus 40 minutes) according to Carlos Calle–Muller, MD, of Henry Ford Hospital in Detroit, and colleagues. Those who had chest pain lasting less than 5 minutes always had a good outcome, with no acute MIs or deaths within 30 days, as reported in the journal Critical Pathways in Cardiology.

If the clinical assessment and ECG are benign, such patients might be able to be discharged directly from the emergency department without stress testing for outpatient follow-up.

The median chest pain duration was 180 minutes among the 10 patients who died and only 40 minutes for the others.

Among patients with acute MI, longer chest pain duration was not associated with higher 30–day mortality, but it was associated with a higher initial level of cardiac troponin-I.