Mitral annulus size links ventricular dilatation to functional mitral regurgitation.
We compared the impact of annulus size and valve deformation (tethering) on mitral regurgitation in the animal dilated cardiomyopathy model, and assessed if acute left ventricular volume changes affect mitral annulus dimensions. We performed 3-dimensional echocardiography in 30 open-chest dogs with pacing-induced cardiomyopathy. Mitral annulus area was calculated from its two orthogonal diameters, whereas valve tethering was quantified by valve tenting area measurement. Mitral valve regurgitant volume showed the highest correlation with annulus area (r = 0.64, P < .001), left atrial volume (r = 0.40, P < .01), and left ventricular end-diastolic volume (r = 0.37, P < .01). Regurgitant volume showed poorer correlation with valve tethering in both septolateral and intercommissural planes (r = 0.35 and r = 0.31, P < .05 for both). Annulus dimensions correlated with acute changes of left ventricular end-diastolic volume (r = 0.68, P = .002). Mitral annulus dilation is the strongest predictor of functional mitral regurgitation in this animal dilated cardiomyopathy model.
Popović
Zoran B
ZB
Department of Cardiovascular Medicine, The Cleveland Clinic Foundation, Cleveland, Ohio 44195, USA.
Martin
Maureen
M
Fukamachi
Kiyotaka
K
Inoue
Masahiro
M
Kwan
Jun
J
Doi
Kazuyoshi
K
Qin
Jian Xin
JX
Shiota
Takahiro
T
Garcia
Mario J
MJ
McCarthy
Patrick M
PM
Thomas
James D
JD
D000818:Animals; D002311:Cardiomyopathy, Dilated / Q000000981:diagnostic imaging* / Q000209:etiology; D004285:Dogs; D004452:Echocardiography / Q000379:methods; D008943:Mitral Valve / Q000000981:diagnostic imaging*; D008944:Mitral Valve Insufficiency / Q000000981:diagnostic imaging* / Q000209:etiology; D008946:Mitral Valve Stenosis / Q000000981:diagnostic imaging* / Q000209:etiology; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013223:Statistics as Topic; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging* / Q000209:etiology