Impact of clopidogrel resistance on ST-segment resolution and no-reflow in acute myocardial infarction with ST-elevation patients treated with a primary percutaneous coronary intervention.

Introduction: A rapid restoration of epicardial coronary flow in acute myocardial infarction is crucial for saving jeopardized myocardium. The no-reflow phenomenon is one of the major problems in a primary percutaneous coronary intervention (PCI) and may be defined as an outcome of different pathological pathways. Our aim was to evaluate clopidogrel resistance in patients who underwent primary PCI and the relationship with the no-reflow phenomenon.

Materials And Methods: A total of 127 patients (mean age 54.0 ± 11.4 years, 83.7% men) were assessed for this purpose. No-reflow was defined as less than 50% ST-segment resolution on ECG.

Result: No-reflow was significantly frequent in patients with clopidogrel resistance (25.3 vs. 57.1%, P=0.006). Univariate analysis and multivariate analysis showed that clopidogrel resistance and anterior myocardial infarction were only independent predictors of no-reflow phenomenon in patients treated with a primary PCI during acute myocardial infarction.

Conclusion: Our study showed that clopidogrel resistance may be one of the responsible mechanisms for the no-reflow phenomenon. Assessment of simple ECG after a primary PCI may help clinicians to determine patients with a poor prognosis.