Objectives
to investigate whether in-ambulance abciximab initiation, in ST-elevation myocardial infarction (STEMI) patients improves ST segment resolution (STR) after primary percutaneous intervention (PCI).
Methods
MISTRAL is a prospective randomized double blind study conducted in 11 centers in France (ClinicalTrial.gov number NCT 00638638). 256 patients with STEMI within 6 hours from symptom onset were allocated to receive Abciximab started either in the Mobile Intensive Care Unit (MICU) or later in the cathlab after diagnostic angiography. Other treatments in the MICU included aspirin 250 mg IV, heparin 40 UI/kg IV. Primary endpoint was complete (>70 % ) ST-segment resolution was adjudicated by an independent centralized ECG-Corelab.
Results
mean age was 56 ¡À 12 years old and 80 % of the patients were males. Median delay from symptoms to diagnosis was 90 min and 103 min min from diagnosis to balloon. Complete ST resolution was similar in the early and late groups 21 % vs 15 % (p = 0.44) before PCI and 70 % vs 67 % (p = 0.67) 60 min after PCI. Mean residual ST elevation tended to be lower in the early group before PCI 8.1 vs 9.6 mm (P = 0.17) but not after PCI 3.0 vs 3.2 mm (p = 0.62). In the early group, TIMI 2? flow rate before PCI tended to be higher (45 vs 34 % , p = 0.095) and distal embolisation rate was lower (8 vs 21 % , p = 0.008). TIMI 2? flow rate post-PCI, blush score rates, LVEF, biologic infarct size, 30 days MACE were similar in both groups with very low mortality rates (1.7 vs 0.8 % ).
Conclusions
early ambulance vs. routine cathlab administration of abciximab in STEMI did not improve ST resolution post-PCI, final TIMI flow rate, LVEF, infarct size and MACE. Early ambulance abciximab tended to improve TIMI 2? flow rates pre-PCI and to reduce slow flow and distal embolisation during procedure. Early abciximab tends to ¡°facilitate?PCI procedure since more arteries are opened at the time of angio (45 vs 34 % TIMI2?) and less embolisation or slow flow occurs during procedure.
