Dear Editor,In the September 2018 edition of the “International Journal of Cardiology Heart and Vasculature” Alvitigala et al. [1] reported that “mean platelet volume (MPV) and platelet distribution width (PDW) were significantly increased in STEMI patients than the control group. The developed cut-off values in a fair sensitivity and specificity could be used in clinical practice”. However, there is major limitation about MPV levels in this study.In this study, MPV measurement technique is not written. Pre-analytical variables, such as the anticoagulant used, and the time between blood collection and measurement are known to significantly affect MPV measurements. Although EDTA is traditionally used and recommended for samples destined for blood counting it is well known that platelets collected into EDTA anticoagulants undergo time-dependent platelet swelling and activation [[2], [3], [4]]. The case control nature of the study leads to a significant problem because the MPV results could not be standardized.