The influence of residential distance on time to treatment in ST-elevation myocardial infarction patients

AIMS To evaluate the relation between residential distance and total ischaemic time in patients with acute ST-elevation myocardial infarction (STEMI). METHODS STEMI patients were transported to the Isala Hospital Zwolle with the intention to perform primary percutaneous coronary intervention PCI (pPCI) from 2004 until 2010 (n = 4149). Of these, 1424 patients (34 %) were referred via a non-PCI 'spoke' centre ('spoke' patients) and 2725 patients (66 %) were referred via field triage in the ambulance (ambulance patients). RESULTS A longer residential distance increased median total ischaemic time in 'spoke' patients (0-30 km: 228 min, >30-60 km: 235 min, >60-90 km: 264 min, p < 0.001), however not in ambulance patients (0-30 km: 179 min, >30-60 km: 175 min, >60-90 km: 186 min, p = 0.225). After multivariable linear regression analysis, in 'spoke' patients residential distance of >30-60 km compared with 0-30 km was not independently associated with ischaemic time; however, a residential distance of >60-90 km (exp (B) = 1.11, 95 % CI 1.01-1.12) compared with 0-30 km was independently related with ischaemic time. In ambulance patients, residential distance of >30-60 and >60-90 km compared with 0-30 km was not independently associated with ischaemic time. CONCLUSION A longer distance from the patient's residence to a PCI centre was associated with a small but significant increase in time to treatment in 'spoke' patients, however not in ambulance patients. Therefore, referral via field triage in the ambulance did not lead to a significant increase in time to treatment, especially at long distances (up to 90 km).