Thrombolytic therapy for myocardial infarction facilitated by mobile coronary care.

BACKGROUND: The benefit of Thrombolytic Therapy (TT) for acute myocardial infarction is time sensitive. In Northern Ireland widespread availability of mobile coronary care units facilitates delivery of TT to heart attack victims. This region-wide prospective observational study assessed the efficacy of various methods of delivery of TT. METHODS: All 15 acute hospitals providing acute coronary care in Northern Ireland participated and data were collected prospectively over six months on all patients admitted with acute myocardial infarction or who received TT. The information was analysed regarding appropriateness of TT, methods and timeliness of delivery of TT and mortality rates. Performance was measured against National Service Framework standards. FINDINGS: Of 1638 patients with acute myocardial infarction 584 were considered eligible for TT and 494 (85 %) received it, in addition to 18 patients without infarction. Of the 512 thrombolysed patients 282 (55%) were treated in hospital coronary care units, 131 (26%) were treated pre-hospital, 97 (19%) in accident and emergency departments, and two in general medical wards. Overall median call-to-needle time was 87 (7-1110) mins and this was shortest for pre-hospital treatment when 55% of call-to-needle times were < or = 60 mins. For patients treated in hospital median door-to-needle time was 46 (0-1065) mins and this was shortest when TT was administered by accident and emergency staff, when 65% of door-to-needle times were < or = 30 mins. In patients with ST elevation myocardial infarction TT was associated with lower mortality, especially when administered pre-hospital. INTERPRETATION: NSF targets for TT are unlikely to be met in Northern Ireland without increasing pre-hospital delivery of TT and by improving collaboration between coronary care and accident and emergency staff with TT availability in accident and emergency departments.