.
http://www.tcmonline.org/article/S1050-1738(16)30029-9/fulltext
.
The anterior mitral leaflet attaches at its base to the aortic valve and accounts for one third of the annular circumference
.
The posterior leaflet, which is attached to the remaining two-thirds of the annular circumference, is scalloped in appearance and can be divided into three segments: lateral (P1), middle (P2), and medial (P3) [10]. It attaches to the annulus that is in continuity with posterior LA wall, an anatomical setup that may allow for the potential development of functional MR in the setting of LA remodeling, as will be discussed below.
.
During ventricular systole, the mitral annulus undergoes sphincteric contraction (decreasing area of the mitral orifice) and folds across its intercommissural axis [11], and appropriate annular motion is required for successful leaflet coaptation.
.
Os detalhes da anatomia e da funcionalidade sugerem dois componentes separados.
Um fortemente ligado à Aorta e outro à parede posterior do átrio. Para não vazar, o anel deve contrair na sístole, diminuindo a área.
.
E a arritmia?
The pathophysiology likely involves the interplay between longstanding alterations in effective atrial contraction, chronic left atrial remodeling and dilation, and mitral annular remodeling and dilation. Recently, Ring et al. have demonstrated using 3-dimensional transesophageal echocardiography that the mechanism of regurgitation in AFMR ultimately results in a loss of mitral leaflet apposition
.
E a dilatação do átrio?
.
LA dilation is clearly associated with AF, and may both lead to and result from the arrhythmia.
.
Moral da história:
Os mecanismos de refluxo Mitral na FA são complexos e interdependentes.
Muito cuidado ao analisar uma insuficiência mitral e dar um laudo indicativo de intervenção.
Você têm que estar seguro do grau de insuficiência e de repercussão da valvopatia na presença de FA!!!