Cardiac Function Assessment Based on Speckle Tracking Imaging for Survival Prediction of Septic Shock Patients After Fluid Resuscitation

Background: Myocardial injury is recognized in septic shock patients. We investigate the changes over time in parameters of cardiac structure measured by speckle tracking echocardiography (STE) of septic shock patients after fluid resuscitation, and examine their potential as the predictors for prognosis. Methods: 58 septic shock patients were selected and stratified into death group (n = 20) and survival group (n = 38) according to their survival status. Left ventricular ejection fraction (LVEF), global longitudinal strain (GLS) and global circumferential strain and (GCS) were quantified via STE on four occasions after admission. The level of cardiac biomarkers, were measured over the corresponding period. The association between changes in STE parameters and cardiac biomarkers was defined with linear regression models. The predictive value of STE parameters is studied via receiver operating characteristic (ROC) curve. The incremental predictive value of considering multiple factors is quantified via ROC and integrated discrimination improvement (IDI). Results: Before fluid resuscitation, GCS value was shortened in the deceased group compared to the survival group (-15.98% vs. -17.66.98%, P < 0.05), whereas the GLS and LVEF did not show significant difference. GCS and serum NT-proBNP in septic shock group were significantly correlated (r = -0.919, P < 0.05). Compared to consider GLS on 1-day alone, adding GCS on 1-day to prognosis prediction improved the area under curve in ROC curve from 0.667 (95% Confidence Interval: 0.522 to 0.812) to 0.854 (95% Confidence Interval: 0.735 to 0.973). The IDI was estimated to be 0.265. Conclusion: For septic shock patients, the joint consideration of GLS and GCS before fluid resuscitation improves prognosis prediction. It is suggested that STE may be used in risk assessment of septic shock patients in ICU.