Improving call-to-balloon times for ST-elevation myocardial infarction

Abstract

Objectives: The National Infarct Angioplasty Project (NIAP) pilots were set up in 2005 to test the feasibility of implementing a countrywide primary angioplasty (PCI) service for patients with ST-elevated myocardial infarction in England. The authors undertook an evaluation of these pilot sites along with a small number of control sites to assess the workforce and staff implications, patient and carer experience and the cost-effectiveness of primary angioplasty-based care in the real world. Methods: this was a mixed methods study, incorporating four main components: description of models of service delivery, evaluation of workforce and organizational issues, patient and carer evaluation and economic evaluation. Results: pilot sites varied considerably in size and configuration. Many offered ambulance bypass for patients within the catchment for nearby feeder (non-PCI) hospitals or received transfers from these non-PCI hospitals. During the pilot year, 70% (1449/2072) of patients were admitted directly to a PCI site, with a further 21% (435/2072) being transferred from a non-PCI site. Median call-to-balloon times (CTB) were 120 minutes for patients taken directly to a PCI site and 161 minutes for patients who went via a non-PCI site. CTB times can be reduced considerably by improving pathways so that ambulances can bypass non-PCI sites and bypass emergency departments by taking patients directly to the catheter laboratory for assessment. The use of telemetry to enable ECGs to be examined by staff within the coronary care unit can also reduce the number of patients being wrongly transferred to primary angioplasty centres. Time delays that incurred from transferring patients from non-PCI sites to PCI sites indicated that promptly administered thrombolysis may be more cost-effective than PCI in certain circumstances. Patients reported very high levels of satisfaction with care and reported higher levels of satisfaction with speed of treatment and the ambulance journey at NIAP site than control sites. Conclusion: primary PCI was found to be a cost-effective and feasible service, providing CTB times can be minimized by streamlining patient pathways.