In-ambulance abciximab administration in STEMI patients prior to primary PCI is associated with smaller infarct size, improved LV function and lower incidence of heart failure: results from the Leiden MISSION! acute myocardial infarction treatment optimization program.

Objectives: Our aim was to evaluate the effects of early abciximab administration in the ambulance on immediate, short, and long term outcomes.

Background: Early abciximab administration before primary percutaneous coronary intervention (PPCI) for ST-segment elevation myocardial infarction (STEMI) is recommended in practice guidelines. However, optimal timing of administration remains indistinct.

Methods: Within a fixed protocol for PPCI, December 2006 was the cut-off point for this prospective study. A total of 179 consecutive patients with STEMI were enrolled, 90 patients received abciximab bolus in the hospital (in-hospital group), and 89 patients received abciximab bolus in the ambulance (in-ambulance group).

Results: The two groups were comparable for baseline and angiographic characteristics. The in-ambulance group received abciximab within the golden period (median 63 min). The infarct related artery (IRA) patency at onset of the PCI was four times higher in the in-ambulance group compared to in-hospital group (odds ratio = 4.9, 95% CI 2.4-10.1). Enzymatic infarct size was smaller in the in-ambulance group (cumulative 48-h CK release 8011 vs. 11267 U/L, P = 0.004). This was associated with higher left ventricular ejection fraction (LVEF) at 90 days post-PPCI measured by myocardial scintigraphy (59% vs. 54%, P = 0.01), and lower incidence of heart failure through a median of 210 days of clinical follow-up (3% vs.11%, P = 0.04).

Conclusion: Early abciximab administration in the ambulance significantly improves early reperfusion in STEMI patients treated with PPCI. Moreover this is associated with a smaller infarct size, improved LV function and a lower risk of heart failure on clinical follow-up.