Indications of platelet indices in coronary artery disease (CAD): more insights into their diagnostic and prognostic importance

As a readily available analysis, the complete blood count (CBC) has interpretative value and provides useful information about diseases, their differential diagnosis, and prognosis. Considering the crucial role of platelets in the pathogenesis of cardiovascular diseases (CVDs), examining their morphological changes can also be of particular interest. Therefore, this review aims to highlight the importance of interpreting platelet indices in coronary artery disease (CAD) and to provide appropriate explanations of the mechanisms behind changes in these parameters. To this end, the study presented here first introduces platelet indices obtained from automated blood cell counters, including mean platelet volume (MPV), platelet distribution width (PDW), platelet large cell ratio (P-LCR), and immature platelet fraction (IPF), while highlighting their interpretative significance in different disease states. This review then continues by discussing and interpreting the parameters mentioned in CAD using previously published data. Since the pathogenesis of CAD is related to various conditions, including inflammatory status, biomechanical forces (caused by non-physiological shear stress), and extracorporeal interventions (particularly during on pump Coronary-artery bypass grafting), despite controversies, changes in platelet indices caused by each of these factors have been proposed as useful markers for monitoring the disease status and its prognosis. Taken together, this review first presents scientific hypotheses to justify the diagnostic value of conventional platelet parameters in CAD patients, while highlighting their prognostic importance under different conditions of disease. The present study also extends its discussion to some neglected analytical parameters, including platelet histogram and its interpretations to further validate the other well-known platelet parameters.