Atrial fibrillation: mechanistic insights and treatment options.

Atrial fibrillation (AF) remains the most common clinically encountered arrhythmia. Unlike supraventricular arrhythmias that use a defined mechanism, AF involves a wide spectrum of arrhythmias from lone AF to paroxysmal to chronic AF. AF is an arrhythmia that may develop in several ways.

Mitral annular remodeling with varying degrees and mechanisms of chronic mitral regurgitation.

Hypotheses: Degree of mitral annular remodeling is directly associated with severity of chronic mitral regurgitation (MR). Mitral annular remodeling occurs in a symmetric fashion, regardless of MR severity. In addition to MR severity, MR mechanism plays a significant role in mitral annular remodeling.

Relationship of mitral annular remodeling to severity of chronic mitral regurgitation.

Hypotheses: (1) Mitral regurgitation (MR) severity is directly associated with mitral annular remodeling as evidenced by mitral annular enlargement. (2) Increasing severity of chronic MR will result in symmetric enlargement of the mitral annulus as measured by annular shape indices.

Background: Limited data exist on mitral annular remodeling for patients with MR.