The association between symptom onset characteristics and prehospital delay in women and men with acute coronary syndrome.

Background: A decision to delay seeking treatment for symptoms of acute coronary syndrome increases the risk of serious complications, disability, and death.

Aims: The purpose of this study was to determine if there was an association between gradual vs abrupt symptom onset and prehospital delay for patients with acute coronary syndrome and to examine the relationship between activities at symptom onset and gradual vs abrupt symptom onset.

Methods: This was a secondary analysis of a large prospective multi-center study. Altogether, 474 patients presenting to the emergency department with symptoms of acute coronary syndrome were included in the study. Symptom characteristics, activity at symptom onset, and prehospital delay were measured with the ACS Patient Questionnaire.

Results: Median prehospital delay time was four hours. Being uninsured (β=0.120, 0.031) and having a gradual onset of symptoms (β=0.138, 0.003) were associated with longer delay. A diagnosis of ST-elevation myocardial infarction (β=-0.205, 0.001) and arrival by ambulance (β=-0.317, 0.001) were associated with shorter delay. Delay times were shorter for patients who experienced an abrupt vs gradual symptom onset (2.57 h vs 8 h, <0.001). Among men with an abrupt onset of symptoms and a ST-elevation myocardial infarction diagnosis, 54% reported that symptoms were triggered by exertion (=0.046).

Conclusion: Patients should be counselled that a gradual onset of symptoms for potential acute coronary syndrome is an emergency and that they should call 911. Men with ischemic heart disease or with multiple risk factors should be cautioned that symptom onset following exertion may represent acute coronary syndrome.