Objectives Evaluation for a potentially life-threatening cardiac event in the emergency department (ED) is a stressful experience that can result in symptoms of post-traumatic stress disorder, which are associated with increased risk of morbidity and mortality in patients. No study has tested whether good clinician–patient communication in the ED is associated with better psychological outcomes in these individuals and whether it can mitigate other risk factors for post-traumatic stress symptoms (PSS) such as perception of life threat and vulnerability in the ED.

Methods Data were analysed from 474 participants in the Reactions to Acute Care and Hospitalization (REACH) study, an observational cohort study of ED predictors of medical and psychological outcomes after evaluation for suspected acute coronary syndrome. Participants were recruited from November 2013 to January 2015 at a single-site academic medical centre (New York-Presbyterian-Columbia University Medical Center). Participants reported threat perceptions in the ED and provided information on their perceptions of clinician–patient communication using the Interpersonal Process of Care Survey. PSS were assessed using the Acute Stress Disorder Scale during follow-up.

Results 474 subjects were enrolled in the study. Median length of follow-up was 3 days after ED presentation, range 0–30 days, 80% within 8 days. Perceptions of good clinician–patient communication in the ED were associated with lower PSS, whereas increased threat perception was associated with higher PSS. A significant interaction between clinician–patient communication and threat perception on PSS suggested that patients with higher threat perception benefited most from good clinician–patient communication.

Conclusion Our study found an association between good clinician–patient communication in the ED during evaluation of potentially life-threatening cardiac events and decreased subsequent post-traumatic stress reactions. This association is particularly marked for patients who perceive the greatest degree of life threat and vulnerability during evaluation.