Mean platelet volume in patients with ischemic heart disease: meta-analysis of diagnostic studies.

It is now widely acknowledged that larger platelets are biologically more active and express a greater prothrombotic potential, but there is no definitive evidence on the diagnostic accuracy role of mean platelet volume (MPV) in patients with ischemic heart disease. We performed an electronic search for articles that have assessed the diagnostic accuracy of MPV in patients admitted at the emergency department with a suspected diagnosis of ischemic heart disease, including articles in which the exact number of true-positive, false-positive, false-negative and true-negative test results could be either directly or indirectly extracted. Heterogeneity was assessed by I(2) test. The cumulative estimates and 95% confidence interval (95% CI) of sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV), area under the receiver operator characteristic (ROC) curve (AUC) and diagnostic odds ratio (DOR) were calculated using a random effect model. Three studies were finally included in our analysis (mean quality score, 10.8) totaling 3577 participants (566 cases and 3011 controls). The between-study variation was high (I(2), 96.2%; P < 0.001). The pooled estimates were 0.820 (95% CI 0.786-0.851) for sensitivity, 0.461 (95% CI 0.443-0.479) for specificity, 0.932 (95% CI 0.918-0.944) for NPV and 0.222 (95% CI 0.205-0.241) for PPV and 0.652 (95% CI 0.596-0.707) for AUC. The DOR was 3.9 (95% CI 2.3-6.5), with 0.52 diagnostic accuracy. The outcome of this meta-analysis suggests that MPV does not meet the requirements for efficient triage of patients in emergency department when used as stand-alone test, whereas its combination with high-sensitive troponin immunoassays merits further investigations.