PMC7650835_01
The patient's 12-lead electrocardiograms. He had LBBB with a QRS duration >150 ms after 2008. The QRS morphology in his chest leads changed into RBBB in May 2016 with a progression of left axis deviation and prolongation of the PQ interval.
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However, the QRS morphology in his chest leads changed to RBBB with progression of the left axis deviation (LAD) and prolongation of the PQ interval (Figure 1).
The clinical course. Hospitalization due to HF in 2008 (63 years). Treatment for non-ischemic cardiomyopathy (ejection fraction: 25-30%) continued after 2008. Change in QRS morphology from LBBB to atypical RBBB in 2016 (71 years). Hospitalization due to HF deterioration in 2017 (72 years). Death due to HF in 2018 (73 years).
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New York Heart Association (NYHA) functional class worsened to III, and he was admitted to our hospital for HF treatment (Figure 2). No significant luminal abnormalities were identified during coronary artery angiography.
(A) M-mode image in the mid-LV short axis view recorded in April 2015 (at the time of LBBB). (B) M-mode image recorded in May 2016 (at the time of atypical RBBB). Arrows indicate the displacement peak of the anteroseptal (dotted arrow) and posterior (inferolateral) wall (solid arrow).
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While the patient exhibited LBBB, the septum contracted earlier than the posterior wall and the SPWMD was 196 ms (Figure 3).
Speckle tracking longitudinal strain (LS) evaluations performed in Mar 2017 (at the time of atypical RBBB). (A) Segmental LS curves in three standard apical views. The yellow arrow indicates the peak of negative strain which appeared within the QRS duration in the basal inferior wall. (B) Bulls-eye maps demonstrating temporal changes in regional LS distribution during the systolic period (QRS onset to aortic valve closing). Negative strain initially appeared in the basal inferior wall (yellow arrow). The contracting area enlarged toward both the septum and lateral regions, and the anterior wall contracted late. The dotted line on the electrocardiogram indicates the time phase of each bulls-eye display.
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The contracting area subsequently enlarged toward both the septum and lateral regions, and the anterior wall contracted late (Figure 4).