Periprocedural myocardial infarction (PMI) represents a frequent complication in patients undergoing percutaneous coronary revascularization. Despite great attention focused on pharmacological prevention of periprocedural damage, very little is known about using biomarkers to potentially predict the risk of PMI. Larger platelets have been associated with enhanced reactivity, increased cardiovascular risk, and higher rates of complications after coronary stenting. The platelet–larger cell ratio (P-LCR) identifies the largest-sized fraction of platelets, the proportion potentially more closely related to thrombotic events. The present study evaluated the relationship between P-LCR and PMI. We included 1,285 patients undergoing PCI. Myonecrosis biomarkers were dosed at intervals from 6 to 48 h after PCI. Periprocedural myonecrosis was defined as troponin I increase by three times the upper limit of normal (ULN) or by 50 % of an elevated baseline value, whereas PMI was defined as an increase in creatine kinase MB by 3 × ULN or 50 % of baseline. We grouped patients according to tertile values of P-LCR (<27.5; ≥35.1). Higher P-LCR was associated with age (P = 0.01), diabetes (P = 0.001), previous cerebrovascular accidents (P = 0.007), therapy with statins (P < 0.001), angiotensin receptor blockers (P < 0.001), aspirin (P = 0.002), and nitrates (P = 0.01). P-LCR was related to hemoglobin levels (P < 0.001), and inversely related to platelet count (P < 0.001) and glycemia (P = 0.05). Patients with higher P-LCR had a lower presence of coronary thrombus (P = 0.003). Higher P-LCR values did not increase the risk of PMI (P = 0.10; adjusted odds ratio (OR) (95 % confidence interval (CI)) = 0.97 (0.69–1.38)), P = 0.89) or periprocedural myonecrosis (P = 0.96; adjusted OR (95 % CI) = 1.003 (0.76–1.32), P = 0.99). Results were confirmed even in higher-risk subgroups of patients. P-LCR does not increase the risk of periprocedural myocardial infarction and myonecrosis in patients undergoing coronary stenting.