2-Hour Accelerated Diagnostic Protocol to Assess Patients With Chest Pain Symptoms Using Contemporary Troponins as the Only Biomarker: The ADAPT Trial

Study Questions:

What is the predictive ability of a new accelerated diagnostic protocol (ADP) for cardiac chest pain in identifying low-risk patients suitable for early discharge?


This prospective observational study tested an ADP that included pretest probability scoring by the Thrombolysis In Myocardial Infarction (TIMI) score, electrocardiography (ECG), and 0 + 2 hour values of laboratory troponin I as the sole biomarker. Patients presenting with chest pain due to suspected acute coronary syndrome (ACS) were included. The primary endpoint was major adverse cardiac event (MACE) within 30 days. The sensitivity, specificity, and positive and negative predictive values for hierarchical primary and secondary events were generated using chi-square analyses for the ADP as a whole and its constituents individually or in combination.


Of 1,975 patients, 302 (15.3%) had a MACE. The ADP classified 392 patients (20%) as low risk. One (0.25%) of these patients had a MACE, giving the ADP a sensitivity of 99.7% (95% confidence interval [CI], 98.1-99.9), negative predictive value of 99.7% (95% CI, 98.6-100), specificity of 23.4% (95% CI, 21.4-25.4), and positive predictive value of 19.0% (95% CI, 17.2-21.0). Many ADP-negative patients had further investigations (74.1%), and therapeutic (18.3%) or procedural (2.0%) interventions during the initial hospital attendance and/or 30-day follow-up.


The authors concluded that using the ADP, a large group of patients was successfully identified as at low short-term risk of a MACE, and therefore, suitable for rapid discharge from the emergency department with early follow-up.


This two-center Australasian study prospectively validated a 2-hour ADP incorporating ECG, TIMI score, and cardiac troponin I. With use of this ADP, a large group (20%) of patients presenting with possible ACS was identified as low risk and suitable for outpatient care. The components required for this strategy are already widely available, and therefore, rapid uptake of the ADP is possible by the majority of hospitals, with a potential for immediate health service and resource utilization benefit. While implementation is ongoing, further prospective validation will solidify the role of this ADP.

Clinical Topics: Acute Coronary Syndromes

Keywords: Myocardial Infarction, Acute Coronary Syndrome, omega-Chloroacetophenone, Chest Pain, Troponin I, Emergency Service, Hospital, Confidence Intervals, Patient Discharge

< Back to Listings