TY - CHAP M1 - Book, Section TI - Mitral Valve Pathophysiology A1 - Timek, Tomasz A. A1 - Fann, James I. A2 - Yuh, David D. A2 - Vricella, Luca A. A2 - Yang, Stephen C. A2 - Doty, John R. PY - 2014 T2 - Johns Hopkins Textbook of Cardiothoracic Surgery AB - The normal mitral valve annulus is a saddle-shaped structure with 3:4 ratio of the anterior–posterior to commissure–commissure distance.Mitral stenosis is usually a result of rheumatic fever, and valvular pathology represents antigen cross-reactivity from Group A streptococcus resulting in valvulitis, myocarditis, or pancarditis.Fibroelastic deficiency and Barlow disease are the predominant forms of degenerative mitral valve disease leading to mitral regurgitation. Fibroelastic deficiency is found in older patients whereas congenitally excessive valve tissue seen in younger patients is observed with Barlow valve.Chordal rupture is the most common etiology of mitral regurgitation in degenerative mitral valve disease.Ischemic mitral regurgitation (IMR) is associated with a localized left ventricular infarct with subsequent chamber remodeling and perturbation in the subvalvular apparatus. Functional mitral regurgitation (FMR) is associated with end-stage dilated cardiomyopathy.Both FMR and IMR are characterized by subvalvular remodeling and annular dilation.Leaflet remodeling may contribute to the pathophysiology and severity of both IMR and FMR.Annular dilation and perturbed leaflet coaptation tend to be symmetric in FMR and asymmetric in IMR. SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/03/28 UR - accesssurgery.mhmedical.com/content.aspx?aid=1104590332 ER -