Objective. To investigate the diagnostic accuracy and clinical benefit of point-of-care Troponin T testing (POCT-TnT) in the management of patients with chest pain. Design. Observational, prospective, cross-sectional study with followup. Setting. Three primary health care (PHC) centres using POCT-TnT and four PHC centres not using POCT-TnT in the southeast of Sweden. Patients. All patients ≥35 years old, contacting one of the primary health care centres for chest pain, dyspnoea on exertion, unexplained weakness, and/or fatigue with no other probable cause than cardiac, were included. Symptoms should have commenced or worsened during the last seven days. Main Outcome Measures. Emergency referrals, patients with acute myocardial infarctions (AMI), or unstable angina (UA) within 30 days of study enrolment. Results. 25% of the patients from PHC centres with POCT-TnT and 43% from PHC centres without POCT-TnT were emergently referred by the GP ( ). Seven patients (5.5%) from PHC centres with POCT-TnT and six (8.8%) from PHC centres without POCT-TnT were diagnosed as AMI or UA ( ). Two patients with AMI or UA from PHC centres with POCT-TnT were judged as missed cases in primary health care. Conclusion. The use of POCT-TnT may reduce emergency referrals but probably at the cost of an increased risk to miss patients with AMI or UA. 1. Introduction Chest pain is a frequent complaint in primary health care and a daily diagnostic challenge to the general practitioner (GP). The outcome of GPs’ diagnostic capability has been investigated and clinical decision rules have been suggested based on history, symptoms, signs, and electrocardiogram findings [1–5]. Elevation of cardiac-specific troponins, for example, Troponin T, is one of the cornerstones in diagnosing acute myocardial infarction (AMI) in hospital care [6]. The additional value of point-of-care Troponin T testing (POCT-TnT) in primary health care has not been fully evaluated [7–9]. On one hand, support from POCT-TnT may reduce referrals to the emergency room, but on the other hand a very recent AMI or unstable angina (UA) may be overlooked if the GPs rely too much on a laboratory finding. The aim of this study was to investigate the diagnostic accuracy and clinical benefit of POCT-TnT in the management of patients with chest pain in a primary health care setting. 2. Material and Methods 2.1. Study Design The study was performed between May 2009 and January 2011 in the county of ？sterg？tland, situated in the southeast of Sweden. It was an observational, prospective, crosssectional study with followup.
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