Abstract Aims To investigate the LBBB Selvester Scoring System (LBBB-SSc) and the Simplified-SSc prognostic impact in predicting response to CRT, all cause and cardiac mortality, heart failure (HF) hospitalizations and onset of arrhythmias in HF patients undergoing CRT. Methods We retrospectively evaluated LBBB-SSc and Simplified-SSc of 172 consecutive HF patients with true-LBBB who underwent CRT. Response to CRT was defined as the improvement of LVEF of at least 10% or as the reduction of LVESV of at least 15% at 6-month follow-up. Logistic regression analysis and Cox proportional hazard analysis were performed to evaluate each endpoint related risk according to LBBB-SSc and Simplified-SSc. Results The LBBB-SSc and the Simplified-SSc were inversely correlated with response to CRT. Myocardial scar at both scores was independently associated to non-response to CRT. No correlation was observed between LBBB-SSc or Simplified-SSc and other endpoints. Conclusions In HF patients with true-LBBB, Simplified-SSc is able to predict response to CRT.