Inflammatory and Hematological Indices as Simple, Practical Severity Predictors of Microdysfunction Following Coronary Intervention: A Systematic Review and Meta-Analysis

C-reactive protein (CRP) and high-sensitivity CRP (hsCRP), along with a series of hematological indices, platelet to lymphocyte ratio (PLR), neutrophil to lymphocyte ratio (NLR), mean platelet volume (MPV), platelet distribution width (PDW), and red blood cell distribution width (RDW), are regarded to be related to the incidence of no-reflow or slow flow. Clinical studies were retrieved from the electronic databases of PubMed, EMBASE, Google Scholar, Clinical Trials, and science direct from their inception to August 24, 2019. A total of 21 studies involving 7403 patients were included in the meta-analysis. Pooled analysis results revealed patients with higher hsCRP (odds ratio [OR] = 1.03, 95% confidence interval [CI], 1.01-1.05, P = .006), hsCRP (OR = 1.04, 95% CI: 1.0-1.08, P = .012), NLR (OR = 1.23, 95% CI: 1.11-1.37, P < .0001), PLR (OR = 1.13, 95% CI: 1.07-1.20, P < .0001), and MPV (OR = 2.13, 95% CI: 1.57-2.90, P < .0001) all exhibited significantly higher no-reflow incidence, but there was no significant association between no-reflow risk and RDW or PDW. Patients with higher CRP/hsCRP also performed higher rate of slow flow (OR = 1.06, 95% CI: 1.01-1.11, P = .018). Preangiographic CRP/hsCRP could independently predict no-reflow and slow flow. Moreover, some hematological indices are associated with no-flow.