Left atrial and left atrial appendage systolic function in patients with post-myocardial distal blocks

Area of Science:

• Cardiology
• Cardiac Electrophysiology
• Echocardiography

Background:

• Myocardial infarction (MI) can lead to intracardiac conduction disturbances.
• The functional impact of these disturbances on the left atrium (LA) and left atrial appendage (LAA) requires further investigation.

Purpose of the Study:

• To evaluate the systolic function of the LA and LAA in patients following myocardial infarction (MI).
• To assess the influence of specific conduction disturbances, including left bundle branch block (LBBB), right bundle branch block (RBBB), and left anterior hemiblock (LAHB), on LA and LAA function post-MI.

Main Methods:

• The study included 59 patients with post-MI conduction disturbances, categorized into LBBB, RBBB, and LAHB subgroups.
• Control groups consisted of patients with MI without conduction disturbances and healthy individuals.
• Transthoracic echocardiography (TTE) and transoesophageal echocardiography (TOE) were utilized to assess LA and LAA systolic function.

Main Results:

• Patients post-MI without conduction disturbances showed enhanced LA systolic function.
• LA systolic function enhancement was also observed in RBBB and LAHB groups, though to a lesser extent.
• A trend towards deteriorated LA systolic function was noted in the LBBB group, but LBBB did not negatively impact LAA systolic function.

Conclusions:

• Left atrial appendage (LAA) systolic function demonstrated improvement in all patients after myocardial infarction (MI).
• This enhancement of LAA function occurred irrespective of the presence or type of complicating conduction disturbances.