Definition of time stamps and intervals in STEMI screening and diagnosis
| TIME STAMP | CARE INTERVAL | DEFINITION |
| Symptom onset time | Time of symptoms prior to arrival | Recalled patient reported time for when symptoms associated with the acute STEMI encounter began. |
| Time zero | ||
| Door time | ED arrival time19 (primary analysis) | First recorded presence of the patient in the ED. |
| Screening | ||
| First (early) ECG time | Door to screening Door-to-first-ECG time, D2E1st (primary independent variable of interest) | ED arrival to completion of the first ECG. The first ECG is generally performed prior to the ED physician evaluation for the purpose of enabling the early identification of STEMI. |
| Diagnosis | ||
| Diagnostic ECG time | Door-to-diagnostic ECG, D2ED
x
(secondary independent Variable of Interest) | ED arrival to completion of ECG used to activate the cath lab. |
| Cath lab activation time | Door-to-catheterisation laboratory activation | ED arrival to the time when the cath lab was activated (Code STEMI). |
| Treatment | ||
| Patient arrives in cath lab | Door-to-catheterisation laboratory arrival time, diagnostic team centric (primary outcome) | ED arrival to patient arrival in the cath lab. |
| Balloon time | Door-to-balloon time, Intervention team centric outcome (primary outcome) | Time from ED arrival to time the catheterisation guidewire crossed the culprit coronary lesion in patients receiving balloon angioplasty. |
Time zero, start time for emergency care. Outcomes, treatment times for patient with STEMI directed to percutaneous coronary intervention. Cath Lab, cardiac catheterisation laboratory; ED, emergency department.