Pre-hospital Wireless Transmission of Electrocardiograms to a Cardiologist Via a Hand-held Device: The TIME Multicenter Study
Pre-hospital Wireless Transmission of Electrocardiograms to a Cardiologist Via a Hand-held Device: The TIME Multicenter Study
Aim: To determine the impact of wireless transmission of prehospital ECGs to a hand-held computer on time to treatment and myocardial salvage in acute MI patients.
Background: The TIME-1 investigators documented a 27% (109 to 80 minutes) reduction of time from EMT arrival at the scene to successful primary PCI implementing pre-hospital ECG transmission to the ED. ECG transmission directly to a physician's cellular phone/PDA through a wireless modem has only recently become an option. The recently completed TIME-NorthEast (NE) study tested the Welch Allyn version of this system and the results show a reduction in time to reperfusion for acute MI patients by 66 minutes (116 to 50).
Methods: This study will involve approximately 20 sites around the country. The study will be divided into two phases: a consecutive control data collection phase (Phase I) and an intervention with concurrent control phase (Phase II). Phase II will begin after installation of Welch Allyn ECG transmission equipment. The primary end-point will be time to reperfusion and secondary end-points will include myocardial salvage, aborted infarction and hospital mortality. ECG measurements will be made at a central ECG core lab by a blinded investigator.
Data Analysis: Patient characteristics for the three periods were compared with the chi-square statistic for categorical variables and one-way analysis of variance for age. The Wilcoxon rank-sum statistic was used to compare time-to-reperfusion in the pre-study and study periods as well as in the Group 1 post-study period. Comparisons were performed separately for EMS and self-transport groups.
Inclusion Criteria:
All patients with a diagnosis of acute STEMI defined as 1 mm ST segment elevation in two spatially contiguous leads were included. There were two major subgroups: emergency medical services (EMS) and self-transport patients. Self-transport patients, who did not have PH-ECG transmission, served as a comparison group.
Exclusion Criteria: