Spotlight on Research

Abstract

Obtaining a prehospital 12-lead electrocardiograph (ECG) in cases of suspected acute myocardial infarction is routine practice in UK prehospital care and is key to early diagnosis and activation of a primary percutaneous coronary intervention (PCI) team. This two-phase prospective observational study took place in the USA to establish whether independent paramedic interpretation of the 12-lead ECG has appropriate positivepredictive value (PPV) to justify activation of the PCI team, or whether there is benefit to using telemetry for physician review. In Phase I, paramedics looked for ECG evidence of ST-elevation and were responsible for mobilizing the PCI team; in Phase II the ECG was transmitted to the emergency department and reviewed by an emergency physician (EP) before mobilizsing the PCI team. Cardiologist confirmation of a STEMI on the prehospital 12-lead ECG was 42/54 (78%) in Phase I and 54/56 (96%) in Phase II. Disposition to emergent PCI occurred in 38/54 (70%) Phase I patients and 51/56 (91%) Phase II patients. This suggests that transmission to an emergency physician improves the PPV of the prehospital 12-lead ECG. The study limitation of greatest importance for extrapolation to UK practice was that unlike UK paramedics, these paramedics had no previous experience of looking for ST-elevation on a 12- lead ECG. It would be expected that the PPV of UK paramedics should be higher but a UK-based study is necessary to answer the question.