Open AccessLeft Ventricular Contraction Sequence in a Case Where the QRS Changed from Left to Atypical Right Bundle Branch Block
Author(s) -
Hideyuki Hara,
Toshio Nagata,
Hiroshi Ito,
Shinichi Niwano,
Junya Ako
Publication year - 2020
Publication title -
international medical case reports journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.198
H-Index - 11
ISSN - 1179-142X
DOI - 10.2147/imcrj.s269576
Subject(s) - right bundle branch block , medicine , cardiology , left bundle branch block , contraction (grammar) , qrs complex , anatomy , bundle branch block , electrocardiography , heart failure
A subgroup of right bundle branch block (RBBB) patients may exhibit a significant left ventricular (LV) activation delay. We evaluated echocardiography in a non-ischemic heart failure patient whose QRS morphology changed from left bundle branch block (LBBB) to atypical RBBB. The septum to posterior wall motion delay (SPWMD) measured using the M-mode was 196 ms while the patient presented with LBBB but decreased to 32 ms after the morphology changed to RBBB. These changes were also associated with delayed appearance of the septal displacement peak. Speckle tracking longitudinal strain was evaluated using three standard apical views after the morphology changed to RBBB. The LV contraction initially appeared in the basal inferior wall and there was delayed anterior wall contraction. The LV contraction pattern in our patient changed when the QRS morphology changed to atypical RBBB. A specific LV contraction sequence observed in atypical RBBB may reflect a significant LV activation delay between the inferior and anterior wall.