In search of the “true” left bundle branch block: The art of asking research questions

Conduction system pacing (CSP) is a promising new approach for delivering pacing therapy. 1 Chung M.K. Patton K.K. Lau C.-P. et al. 2023 HRS/APHRS/LAHRS guideline on cardiac physiologic pacing for the avoidance and mitigation of heart failure. Heart Rhythm. 2023; 20: e17-e91 Abstract Full Text Full Text PDF PubMed Scopus (36) Google Scholar CSP offers an elegant treatment solution to the challenging problem of heart failure (HF) caused by electrical dyssynchrony due to left bundle branch block (LBBB). Pacing therapy of LBBB-caused electrical dyssynchrony has a long and successful history. Cardiac resynchronization therapy improves survival and quality of life and reduces HF hospitalizations in HF patients with LBBB. 1 Chung M.K. Patton K.K. Lau C.-P. et al. 2023 HRS/APHRS/LAHRS guideline on cardiac physiologic pacing for the avoidance and mitigation of heart failure. Heart Rhythm. 2023; 20: e17-e91 Abstract Full Text Full Text PDF PubMed Scopus (36) Google Scholar Striving to improve patient outcomes, the field opened the quest for the “true” LBBB. ECG characteristics of “true” left bundle branch block: Insights from transcatheter aortic valve–related LBBB and His-Purkinje conduction system pacing–correctable LBBBHeart RhythmVol. 20Issue 12PreviewLeft bundle branch block (LBBB) pattern on the electrocardiogram includes patients with both complete conduction block in the His-Purkinje system as well as nonspecific left ventricular conduction delay without discrete block. Full-Text PDF