Cardiac Hemodynamics Abnormalities Induced by Intermittent Left Bundle-branch Block: A Case Report

Area of Science:

• Cardiology
• Cardiac Electrophysiology

Background:

• Left bundle-branch block (LBBB) is a conduction abnormality associated with impaired cardiac function.
• Biventricular pacing is a therapeutic option for certain cardiac conditions.

Observation:

• A case study involving a patient with intermittent LBBB undergoing biventricular pacemaker implantation.
• Comparison of left ventricular performance during LBBB, biventricular pacing, and narrow QRS rhythm.

Findings:

• Intermittent LBBB was associated with significantly worse left ventricular performance.
• Biventricular pacing and narrow QRS rhythm (sinus rhythm) demonstrated improved cardiac function.
• LBBB correlated with increased isovolumetric contraction time, prolonged pre-ejection period, and elevated myocardial performance index (Tei index) compared to narrow QRS rhythms.

Implications:

• LBBB can have a detrimental impact on left ventricular function.
• Biventricular pacing may effectively restore or improve cardiac performance in patients with LBBB.
• The Tei index serves as a valuable indicator of myocardial performance in the context of conduction abnormalities.