Figure 2. Showed ROC curve to predict the optimal cut off of CRT non-response predictors, and all p values were less than 0.01.

The optimal cut-off point was in the upper-left area and was calculated based on the maximal Youden index (sensitivity + specificity − 1). (A) Was ROC curve of LAV; (B) was ROC curve of LVESV; (C) was ROC curve of LVEDV; (D) was ROC curve of S wave; (E) was ROC curve of QRS duration; (F) was ROC curve of TpTe/QTc.