The left bundle branch block revised with novel imaging modalities.

Area of Science:

• Cardiology
• Medical Imaging

Background:

• Left bundle branch block (LBBB) is linked to impaired cardiac conduction and mechanical dyssynchrony, often co-occurring with hypertension and coronary artery disease.
• The rising incidence of LBBB and heart failure necessitates enhanced methods for assessing left ventricular (LV) mechanical asynchrony.

Approach:

• This study reviews advanced imaging modalities, including tissue Doppler imaging (TDI), strain (rate) imaging, and tissue tracking, for evaluating LBBB patients.
• Real-time 3D echocardiography and cardiac magnetic resonance imaging (CMR) offer novel regional and quantitative insights into LV mechanical asynchrony.

Key Points:

• LBBB patients exhibit diverse mechanical activation patterns.
• Tissue synchronization imaging and 3D echocardiography visualize and map mechanical asynchrony within the LV.
• CMR-derived strain curves provide further quantification of LV mechanical asynchrony.

Conclusions:

• Novel imaging techniques are crucial for understanding the significant impact of LBBB on cardiac function.
• Myocardial involvement appears to be a key factor in LBBB-associated cardiac dysfunction.
• Continued development of these imaging modalities promises deeper insights into LBBB and cardiac mechanics.