Objectives and Backgrounds Current diagnostic strategies using cardiac markers in the assessment of suspected acute coronary syndrome (ACS) involve the measurement of serum troponin 10–12 h after the onset of chest pain. We evaluated the potential impact of a multimarker strategy using point of care (POC) measurement of myoglobin, creatine kinase (CK)-MB and troponin I to exclude MI in ≤90 min.

Methods Patients presenting to the Emergency Department with suspected ACS with non-diagnostic ECGs were included. We measured myoglobin, CK-MB and troponin I with a POC device at presentation and at 90 min. Standard laboratory testing of troponin I was performed at 12 h. Sensitivity, specificity and likelihood ratios for the POC triple cardiac marker strategy were calculated. We also calculated time to decision point for POC testing vs laboratory testing.

Results Complete data were available for 109 patients. 73 patients had negative POC testing and normal laboratory troponin. POC markers were positive in 36 patients, of which 19 had positive 12 h laboratory troponin I. Sensitivity of POC cardiac markers was 100% (95% CI 0.79% to 1.0%), specificity 81% (95% CI 0.71% to 0.88%), negative likelihood ratio <0.001 and positive likelihood ratio 5.29. Mean time to decision point was 700 min earlier for POC testing vs laboratory troponin measurement. We estimate that implementation of the triple cardiac markers POC pathway in our institution would save 3 beds per day.

Conclusions Triple cardiac marker POC testing at 90 min can be used to reliably exclude acute myocardial infarction in patients with low to moderate risk ACS, and has the potential to reduce inpatient medical bed occupancy.