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) (614±600 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.