Development of a Novel Risk-Prediction Tool for Emergency Department Patients with Symptoms of Coronary Artery Disease: A Research Study Protocol.

Patients with chest pain and symptoms of acute coronary syndromes account for > 600,000 emergency department (ED) visits annually in Canada. Of these patients, 85% do not have acute coronary syndromes, and most are discharged from the ED after a thorough evaluation. However, a large proportion of these patients are referred for outpatient cardiac testing after ED discharge, even though their short-term risk of major adverse cardiac events (MACE), including death, new myocardial infarction, and need for revascularization, is very small. These referrals contribute to substantial low-value healthcare utilization, and limit access for those patients who are more likely to benefit from objective testing.Existing risk-prediction tools-developed prior to the advent of new high-sensitivity cardiac troponin assays-were derived in nonrepresentative populations, and when applied to ED patients with low cardiac troponin concentrations, systematically overestimate the short-term risk of MACE.This multicentre prospective cohort study will enroll ED patients with chest pain to derive and validate a novel risk prediction tool that distinguishes patients at low risk of MACE who do not require further cardiac testing from those who may benefit from additional cardiac testing. We will enroll 6500 patients in 13 Canadian EDs and prospectively follow them to ascertain a primary outcome of MACE within 30 days after their index ED encounter. The risk-prediction tool developed in this project will guide the safe, efficient, and appropriate referral of ED patients with chest pain. Clinical Trial Registration: NCT06743672.