Zhang H, Zhang Q, Chen X, et al. - In this study performed on mechanically ventilated isolated left ventricular systolic dysfunction (ILVD) patients, researchers evaluated inferior vena cava diameter distensibility index (dIVC) as a predictor of fluid responsiveness. They found that in ILVD patients as well as in normal LV function (NLVF) patients, the value of dIVC was equally high. No statistically significant area-under-the-curve (AUC) was generated in a receiver-operating characteristic (ROC) analysis for the ability of dIVC for determining fluid responsiveness from ILVD patients. An AUC of 0.918 (95% CI 0.858–0.978) in NLVF patients was obtained in ROC analysis; this value was higher than the AUC acquired from all patients. Based on these findings, experts recommended exercising caution while using dIVC when critically ill patients on controlled mechanical ventilation exhibit normal right ventricular function in combination with abnormal left ventricular systolic function.