The relation between ejection fraction and mitral annulus motion before and after direct-current electrical...

Area of Science:

• Cardiology
• Echocardiography
• Cardiac Electrophysiology

Background:

• Mitral annulus motion (MAM) and its relationship with left ventricular ejection fraction (EF) differ between sinus rhythm and atrial fibrillation.
• The impact of direct-current (DC) electrical cardioversion on the EF-MAM relationship remains uninvestigated.

Purpose of the Study:

• To investigate the changes in the relationship between EF and MAM after DC electrical cardioversion to sinus rhythm.
• To determine if the conversion factor (CF) normalizes post-cardioversion compared to control subjects.

Main Methods:

• Echocardiography was performed on 31 patients before DC electrical cardioversion.
• 13 patients who maintained sinus rhythm were re-examined 4-8 weeks after cardioversion.
• The conversion factor (CF = EF/MAM) was calculated and compared before and after cardioversion, and with controls.

Main Results:

• The CF significantly decreased from 8.4 ± 1.7 before cardioversion to 5.8 ± 0.8 after cardioversion (P<0.001).
• Left ventricular ejection fraction (EF) showed a slight increase, while mitral annulus motion (MAM) increased significantly, leading to the reduced CF.
• No significant difference in CF was observed between post-cardioversion patients and age- and gender-matched controls with sinus rhythm.

Conclusions:

• DC electrical cardioversion normalizes the EF/MAM relationship 4-8 weeks after the procedure.
• The same conversion factor (CF) used for patients in sinus rhythm can be applied for assessing left ventricular function post-cardioversion.