Association of platelet-to-lymphocyte count ratio with myocardial reperfusion and major adverse events in patients with acute myocardial infarction: a two-centre retrospective cohort study

Objective Insufficient myocardial reperfusion for patients with acute myocardial infarction (AMI) during primary percutaneous coronary intervention (PPCI) has a great influence on prognosis. The aim of this study was to investigate the association of the platelet-to-lymphocyte ratio (PLR) with myocardial reperfusion and in-hospital major adverse cardiac events (MACEs) in patients with AMI undergoing PPCI. Design Retrospective cohort study. Setting Patients and researchers from two tertiary hospitals. Participants A total of 445 consecutive AMI patients who underwent PPCI between January 2015 and December 2017 were enrolled. Patients were divided into two groups based on the PLR value: patients with PLR values in the third tertile were defined as the high-PLR group (n=150), and those in the lower two tertiles were defined as the low-PLR group (n=295). Explicit criteria for inclusion and exclusion were applied. Interventions No interventions. Primary and secondary outcome measures Primary outcome measures were defined as cardiovascular death, reinfarction or target vessel revascularisation. Secondary outcome measures were defined as stroke, non-lethal myocardial infarction, ventricular tachycardia/ventricular fibrillation and in-hospital mortality. Results The high-PLR group had insufficient myocardial perfusion (23% vs 13%, p=0.003), greater postprocedural thrombolysis in myocardial infarction flow grade (0-2) (17% vs 10%, p=0.037), greater myocardial blush grade (0-1) (11% vs 4%, p=0.007) and higher B-type natriuretic peptide (BNP) (614600 vs 316 +/- 429, p<0.001) compared with the low-PLR group. Multivariate logistic regression analysis indicated that the independent risk factors for impaired myocardial perfusion were high PLR (OR 1.256, 95%CI 1.003 to 1.579, p=0.056) and high BNP (OR 1.328, 95%CI 1.056 to 1.670, p=0.015). The high-PLR group had significantly more MACEs (43% vs 32%, p=0.029). Conclusions This study suggested that high PLR and BNP were independent risk factors for insufficient myocardial reperfusion in patients with AMI. Higher PLR was related to advanced heart failure and in-hospital MACEs in patients with AMI undergoing PPCI.