The Relationship Between Mean Platelet Volume , Platelet Distribution Width , Platelet Function and ST Segment Resolution in STEMI Patients Treated With Either Thrombolytic Therapy or Primary Percutaneous Coronary Intervention

Reperfusion therapy as the main treatment strategy in patients with ST-segment elevation myocardial infarction (STEMI) consists of either thrombolysis or primary percutaneous coronary intervention (pPCI). Primary percutaneous coronary intervention is the preferred therapy for STEMI; however, cardiac catheterization laboratories may not be widely available.

Early recanalization of the infarct related artery (IRA) by either thrombolytics or percutaneous coronary intervention (PCI) is the main goal in the treatment of acute myocardial infarction. But the eventual aim is to provide reperfusion at the tissue level as well as in the infarct related artery .

Resolution of ST elevation has been shown as an agreeable marker that reflects both epicardial and myocardial reperfusion . In addition, early and complete resolution of ST -segment in the setting of acute myocardial infarction is associated with smaller infarct size, greater ejection fraction and reduced morbidity and mortality .

Platelets play a critical role in the pathogenesis and prognosis of ACS . They secrete a number of substances that are key mediators of coagulation, thrombosis and atherosclerosis. High-volume platelets have a higher thrombotic potential than small platelets and have concentrated granule contents that are of interest in the development of ACS pathogenesis . Mean platelet volume (MPV) is the most commonly used measure of platelet size and correlates with platelet activity. Platelet distribution width (PDW) is an index reflecting heterogeneous platelet size, whereas the platelet-large cell ratio (P-LCR) is the proportion of large platelets in blood circulation. Generally, higher MPV, PDW and P-LCR are correlated with increased platelet size, although they tend to be overlooked in clinical applications. In fact, these indices, particularly MPV and PDW, correlate with platelet functions.

Percutaneous coronary intervention (PCI) is an effective treatment for acute coronary syndrome (ACS), including ST-elevation myocardial infarction (STEMI) and unstable angina. Despite the efficacy of the technique, preprocedural high-thrombus burden (HTB) is a predictor of procedural complications following primary PCI for STEMI. HTB can lead to poor outcomes, including distal embolization, no-reflow, increased myocardial necrosis and decreased left ventricular function.