Integration between the Tele-Cardiology Unit and the central laboratory: methodological and clinical evaluation of point-of-care testing cardiac marker in the ambulance

The aim of this study was to identify patients with myocardial necrosis in pre-hospital phase during transport by ambulance, without ST-segment elevation (NSTE) on the ambulance ECG. The analytical performance of the i-STAT troponin I (cTnI) method was assessed. A total of 53 NSTE ambulance ECG patients admitted to hospital were followed. The ambulance had experimental software able to receive data from the i-STAT device and transmit it to a protected address and server. cTnI mean values from 2.0 to 34 microg/L showed a total CV of 3.0-5.6%. The detection limit was 0.016 microg/L. A mean cTnI concentration of 0.09 microg/L was associated with a CV of 8.0% (decision limit). The i-STAT cTnI method was linear for concentrations from 0 to 35 microg/L. There was no effect (p<0.05) of interfering substances. For point-of-care testing (POCT), cTnI was >0.09 microg/L in 20 AMI patients (91%). The median ambulance turnaround time (TAT) was 12 min and median hospital TAT was 40 min, a difference of 28 min. The high sensitivity of the i-STAT cTnI method integrated with tele-medicine procedures could play an important role in the management of acute coronary syndrome patients related to the pre-hospital phase (early diagnosis and treatment in the ambulance). These approaches may allow improvements in patient outcomes and continuous monitoring of the POCT network in the central laboratory, thus meeting quality requirements.