Increased mean platelet volume in rheumatic mitral stenosis: assessment of clinical and echocardiographic determinants

The aim of this study was to investigate mean platelet volume (MPV) in patients with rheumatic mitral stenosis (RMS) and to define the determinants of a possible platelet activation reflected as platelet volume enlargement. Peripheral venous plasma value of MPV was measured in 84 consecutive patients (16 men, 68 women; mean age ± SD = 44 ± 13 years) with RMS who had no left atrial thrombus by transoesophageal echocardiography. The control group consisted of 32 healthy subjects (nine men, 23 women; mean age ± SD = 38 ± 7 years). The patients had significantly higher MPV values (mean ± SD = 10.07 ± 0.58 fL) compared to the healthy subjects (mean ± SD = 8.15 ± 0.60 fL, p < 0.001). Among many clinical and echocardiographic variables, left atrial spontaneous echo contrast-positivity (beta = 0.426, p < 0.001) and severe mitral regurgitation (beta = 0.577, p < 0.001) appeared as significant predictors of platelet enlargement in RMS in multiple linear regression analysis. Patients with RMS have increased platelet activity reflected as elevated MPV; and the coexistence of severe mitral regurgitation and presence of left atrial spontaneous echo contrast are determinants of this increment.