Importance of Manchester Triage in acute myocardial infarction: impact on prognosis.

Background: Fast and effective diagnosis of patients with acute myocardial infarction (AMI) in the Emergency Department (ED) is needed. Manchester Triage (MT) is based on identification of the patient's main complaint, establishing, through decision flowcharts, a target-time for first observation. This study aimed to evaluate the impact of MT on short-term mortality in AMI and detect potential improvements, and to analyse high-risk groups: diabetic patients, women and older patients.

Methods: 332 consecutive patients (69.0+13.6 years mean age; 34.9% women) with final diagnosis of AMI were assessed in the ED using MT. Data were analysed according to demographics and risk groups, as well as several AMI parameters, admission duration and intrahospital mortality (IHM). Independent predictors of mortality were determined.

Results: 82.8% of patients met the ideal goal of ≤10 min target-time for a first observation (ITTFO). This was higher (95%) in typical presentations ('chest pain'), versus 52% in other flowcharts; p<0.01. Patients ≥70 years old were less frequently screened with ITTFO ≤10 min (76.2% vs 90.0% in those under 70; p=0.001) or the 'chest pain' flowchart (66.9% vs 77.5%; p=0.031). IHM was 13.3%. Triage with ≤10 min ITTFO and the 'chest pain' algorithm seems to predict a lower mortality (0.33 OR; 95% CI 0.17 to 0.63; p=0.0005 and 0.49 OR; 95% CI 0.24 to 1.03; p=0.056).

Conclusion: MT proved to be an effective system. Patients with typical AMI presentation, ST elevation myocardial infarction and less than 70 years old are protected by MT, with lower ITTFO and better short-term survival.