Abstract
Coronary chronic total occlusion (CTO) is caused by organized thrombi or atherosclerotic plaque progression. The presence of a CTO is an independent predictor of mortality in patients presenting with ST-segment elevation myocardial infarction (STEMI). Platelets have a crucial role in the pathophysiology of atherosclerosis. The aim of this retrospective study was to investigate platelet indices as predictors of CTO in patients with STEMI treated with primary percutaneous coronary intervention (pPCI). A total number of 334 patients admitted for STEMI between January 2011 and December 2013 were included and divided in two groups based on the presence of CTO (48 patients in CTO+ group, 286 patients in CTO-group). Platelet count, mean platelet volume (MPV), platelet distribution width (PDW), platelet-large cell ratio (P-LCR), lymphocyte and neutrophil count determined on admission were analyzed. MPV was larger in patients with CTO compared with patients without CTO (p=0.02), as were PDW (p=0.03) and P-LCR (p=0.01). Platelet-to-lymphocyte ratio (PLT/LYM) was lower in patients with CTO: 105.2 (75.86-159.1) compared to 137 (97-188.1), p<0.01. Receiver-operator characteristic curve analysis identified an area under the curve of 0.61 (95%CI=0.57-0.67, p< 0.01) for PLT/LYM in predicting the presence of a CTO, with a cut-off value at 97.73. Lower values than this were independent predictors of a CTO in multivariate logistic regression analysis, with an Odds Ratio of 2.2 (95%CI=1.15-4.20, p=0.02). Our results support the use of platelet indices and PLT/LYM as predictors of CTO in patients presenting with STEMI.