Speckle-tracking parameters as predictors of left ventricular systolic dysfunction in patients with myocarditis

Abstract

Purpose. To evaluate the prognostic capabilities of speckle-tracking echocardiography for prediction of left ventricular systolic dysfunction persistence after 1-year follow-up of patients with myocarditis. Methods. We included 58 patients with acute diffuse myocarditis and left ventricular (LV) systolic dysfunction – LV ejection fraction (EF) ≤40 % who underwent examination 3 times: within the 1st month after the disease onset, at 6- and 12-month follow-up. Transthoracic 2-dimensional echocardiography (EchoCG) and speckle-tracking echocardiography (STE) were performed with the measurement ofLV end-diastolic volume index (LV EDVi) and LV EF, longitudinal global systolic strain (LGSS) and strain rate (LGSSr), circumferential global systolic strain (CGSS) and strain rate (CGSSr), radial global systolic strain (RGSS) and strain rate (RGSSr). For better clarity, parameters of longitudinal and circumferential strain were presented in absolute values. Results. After 12-month follow-up in comparison with the 1st month we observed improvement of LV EF 43.2 ± 3.1 % vs. 32.2 ± 2.7 % (P < 0.02), respectively, and decrease of LV EDVi 91.1 ± 6.6 ml/m 2 vs. 112.2 ± 7.2 ml/m 2 (P < 0.05), respectively. But statistically significant increase of STE parameters in comparison with their values in the 1st month was indicated after only 6-month follow-up: the absolute value of LGSS increased from 5.40 ± 0.41 % to 8.40 ± 0.63 % (P < 0.01) and the absolute value of CGSS – from 6.60 ± 0.73 to 10.40 ± 0.90 % (P < 0.01). By the 12th month there was a further increase in the absolute values of these indicators which corresponded to the statistically significant increase in LV EF and reduction in LV EDVi. By the use of binary regression analysis we defined cut-off values for STE parameters, measured within the 1st month of myocarditis onset, that with high sensitivity and specificity could predict LV systolic dysfunction persistence after 12 months: LGSS <8.6 %, LGSSr <0.61 s -1 and CGSS <8.3 %. Conclusions. On the basis of dynamic observation we detected STE parameters that within the 1 st month of myocarditis onset could be used for prognostication of LV systolic dysfunction persistence after 1-year follow-up: absolute values of LGSS <8.6 %, LGSSr <0.61 s -1 and CGSS <8.3 %.