RVAC as TAPSE/PASP and TAPSE*PVAT as a novel static parameter to assess fluid responsiveness in septic shock patients, a prospective cohort study

Abstract

A prospective cohort investigation was undertaken between November 2022 and April 2024, encompassing 50 patients with septic shock. The study evaluated fluid responsiveness through the assessment of right ventricular-arterial coupling (RVAC), quantified using the ratios TAPSE/PASP and TAPSE*PVAT, with left ventricular outflow tract velocity–time integral (LVOT-VTI) serving as the comparative parameter. Investigation of the association between non-invasive right ventricular-arterial coupling parameters and LVOT-VTI measurements post-fluid administration for predicting volume responsiveness in septic shock patients. Each participant underwent fluid challenge protocols accompanied by standard echocardiographic evaluations. Right ventricular-arterial coupling parameters, including TAPSE/PASP and TAPSE*PVAT ratios, were documented to determine volume responsiveness. Patient stratification into responsive and non-responsive cohorts was established based on left ventricular outflow tract velocity–time integral (LVOT-VTI) alterations, with increases of ≥ 12% defining the responder category. The mean TAPSE/PASP was (0.63 ± 0.23 vs 0.42 ± 0.17, P = 0.002, Cut-off: 0.47, AUC 0.764, 95% CI:]0.622–0.902[ specificity 78.1% and sensitivity 72.2%) in the responder vs the non-responder group respectively, The mean TAPSE*PVAT was (227.51 ± 45.67 vs 178.52 ± 52.37, P = 0.003, Cut-off: 214.5, AUC 0.722, 95% CI:]0.618–0.896[specificity 71.3% and sensitivity 75%) in the responder vs the non-responder group respectively. RVAC, expressed as TAPSE/PASP, demonstrated predictive value for fluid responsiveness in septic shock. TAPSE × PVAT may serve as an alternative non-invasive parameter.