Transient left bundle branch block and intraventricular dyssynchrony as a cause of reversible left ventricular dysfunction: The "in vivo" documentation of spontaneous electrical remodeling

Abstract

Spontaneous resolution of non-rate-dependent left bundle branch block (LBBB) has been rarely reported. We present the case of a 74-year-old woman admitted with pulmonary edema, a newly diagnosed LBBB and severe left ventricular (LV) dysfunction. Five months later, the patient was asymptomatic, the ECG recording showed complete regression of the LBBB to narrow QRS and LV function completely recovered. However, at one-year follow-up LBBB reappeared together with mild LV dysfunction. Spontaneous resolution of LBBB may be responsible for LV electrical and mechanical reverse remodeling in dyssynchronopathies.

Keywords: ECG; dyssynchronopathy; heart failure; left bundle branch block.

© 2019 Wiley Periodicals, Inc.

Figures

Figure 1

ECG at first admission. Sinus rhythm and broad QRS with typical left bundle branch block morphology (QRS duration 140 ms, inferior axis). The heart rate was 66 bpm

Figure 2

ECG at 8 months. Complete resolution of the left bundle branch block (QRS 90 ms). The heart rate was 79 bpm

Figure 3

Cardiovascular magnetic resonance (CMR) at eight‐month follow‐up. Inversion recovery‐prepared gadolinium‐enhanced T1‐weighted short axis (a) views and T2‐weighted triple‐inversion recovery short axis view (b). The images demonstrate that there was neither late gadolinium enhancement nor myocardial edema on specific sequences

Figure 4

ECG at one year. Reoccurrence of left bundle branch block morphology. The heart rate was 70 bpm