Significance of mitral annulus apparatus morphometry in patients with persistent atrial fibrillation

Abstract Background Few data about mitral valve apparatus components deformation in patients with persistent atrial fibrillation are available. Four-dimensional transesophageal echocardiography (4DTEE) is an ideal imaging technique to evaluate the complex morphology of the mitral valve apparatus. Purpose The study aimed to find some characteristics in patients presenting with persistent atrial fibrillation and if some of them could be indicative of relapse after cardioversion. Methods The study enrolled 133 patients with persistent atrial fibrillation and mild/moderate functional mitral regurgitation (FMR) before cardioversion. 101 of the patients were at the first persistent atrial fibrillation episode, and 32 with relapse. After performing two-dimensional transthoracic echocardiography (2DTTE), the study included only patients with mild/moderate FMR. 4D TEE permitted a detailed examination of the mitral annulus and valve leaflets, using an E95 machine for acquisition and an ECHOPAC 204 for image postprocessing with mitral valve quantification (MVQ) software. The studied measured: annulus area (AA)3D, annulus perimeter (AP), antero-posterior diameter (APD), posteromedial-anterolateral diameter (PM-ALD), commissural diameter (CD), inter-trigonal distance (ITd), non-planar angle (NPa), mitral-aortic angle (MAa), and for the leaflets, morphological measured parameters were: anterior leaflet area (ALA), posterior leaflet area (PLA), anterior leaflet length (ALL), posterior leaflet length (PLL), anterior leaflet angle (ALa), posterior leaflet angle (PLa), tenting height (TH), tenting area (TA), tenting volume), closure line length (CLL). Results 1. We found significant statistic differences between mitral annulus apparatus components in patients with (32) and without relapse (101) after initial cardioversion: AA 3D: 3.12 vs. 11.65 (p=0.003), AP: 13.23 vs. 12.1 (p=0.0001), APD: 3.76 vs. 3.45 (p=0.0003), PM-ALD: 4.21vs 3.93 (p=0.004), CD:4.17 vs. 3.89 (p=0.002), ITd: 2.82 vs 2.74 (p=0.2), NPa: 158.5 vs 155.2 (p=0.09), MAa: 122 vs 120,7 (p=0.5), ALA: 5.73 vs. 5.18 (p=0.006), PLA: 7.04 vs. 6.09 (p < 0.0001), ALL: 2.19 vs. 2.07 (p=0.036), PLL: 1,73 vs. 1,6 (p=0.03), ALa: 15.31 vs. 18.82 (p=0.002), PLa: 21.38 vs. 25.31 (p=0.01), TH: 0.83 vs. 0.63 (p=0.001), TA: 1.63 vs. 1.32 (p=0.007), TV: 2.75 vs. 2.13 (p=0.007). 2. We found correlations between mitral valve leaflets area and coaptation length in atrial fibrillation patients with (ALA: r=0.72, PLA r=0.65) and without relapse. (ALA: r=0.76, PLA r=0.64). Conclusions 1. 4D TEE identified a more significant mitral annulus and leaflet remodeling in atrial fibrillation patients with relapse after initial cardioversion than in atrial fibrillation patients admitted with a first atrial fibrillation episode. 2. Mitral valve leaflets area correlated with the coaptation length. 3. Mitral annulus complex morphology in patients with atrial fibrillation could be essential in predicting relapse after initial cardioversion.Mitral annulus parameters evaluationMitral leaflets parameters evaluation