Primary percutaneous coronary intervention (PCI) is the preferred method of reperfusion in ST-segment elevation myocardial infarction patients. Adjunctive pharmacotherapy is, however, still under investigation.Objective
To assess the effect of combined pharmacologic therapy on myocardial perfusion and infarct size in relation to time delays.Materials and methods
We studied 309 consecutive ST-segment elevation myocardial infarction patients admitted within 12 h from symptom onset with (a) chest pain persisting for more than 30 min, (b) ST-segment elevation more than 1 mm in at least two contiguous leads, and (c) pretreatment with 600 mg of clopidogrel, 300 mg of aspirin, and 5000 U of intravenous heparin. Group I (n=90) included patients transferred directly to cathlab (immediate transfer) and group II (n=219) included patients transferred by referring hospitals (staged transfer). The results of thrombolysis in myocardial infarction (TIMI) flow before and after PCI, ST-segment resolution (STSR), troponin T level, and myocardial blush grade were analyzed in relation to delay to intervention.Results
The delay between pharmacologic pretreatment and angiography was two times longer in cases of staged transfer (80 vs. 47.5 min; P<0.0001). Despite the longer delay, higher rates of preangiography total STSR (26.4 vs. 15.5%; P=0.039) and initial TIMI flow 3 (20.1 vs. 11.1%; P=0.059) were observed in those patients. Differences in the rate of total STSR (70.3 vs. 66.7%; P=0.52), TIMI flow 3 (91.3 vs. 88.9%; P=0.33), and myocardial blush grade (60.7 vs. 63.3%; P=0.66) were no longer observed after PCI. Similarly, the peak troponin T level was also comparable (3.6 vs. 3.9 ng/ml; P=0.74).Conclusion
Pretreatment with a combination of antiplatelet and antithrombotic agents may improve myocardial perfusion and compromise longer delay to a mechanical intervention.