Determinants of functional mitral regurgitation severity in patients with ischemic cardiomyopathy versus nonischemic dilated cardiomyopathy.
OBJECTIVE
Functional mitral regurgitation (MR) is prevalent among patients with left ventricular (LV) dysfunction and is associated with a poorer prognosis. Our aim was to assess the primary determinants of MR severity in patients with ischemic cardiomyopathy (ICM) and nonischemic dilated cardiomyopathy (DCM).


RESULTS
Patients with functional MR secondary to ICM (n = 55) and DCM (n = 48) were prospectively enrolled. Effective regurgitant orifice (ERO) area, global LV remodeling, regional wall-motion abnormalities, and mitral apparatus deformity indices were assessed utilizing conventional and tissue Doppler echocardiography. ICM patients had more severe MR compared with DCM patients despite similar ejection fraction and functional status (ERO = 0.16 ± 0.08 cm(2) vs. ERO = 0.12 ± 0.70 cm(2) , respectively, P = 0.002). Regional myocardial systolic velocities in mid-inferior and mid-lateral wall were negatively correlated with ERO in ICM and DCM patients, respectively. Multivariate analysis identified coaptation height as the only independent determinant of ERO in both groups. In a subset of ICM patients (n = 9) with relatively high ERO despite low coaptation height, a higher prevalence of left bundle branch block was detected (88.9% vs. 46.7%, P = 0.02).


CONCLUSIONS
Functional MR severity was chiefly determined by the extent of mitral apparatus deformity, and coaptation height can provide a rapid estimation of MR severity in heart failure patients. Additional contributory mechanisms in ICM patients include depressed myocardial systolic velocities in posteromedial papillary muscle attaching site and evidence of global LV dyssynchrony.
First Department of Cardiology, AHEPA University Hospital, Aristotle University Medical School, Thessaloniki, Greece; Heart Failure Care Group, Royal Brompton Hospital, London, United Kingdom.
Dimitrios M
DM
Konstantinou
Klio
K
Papadopoulou
George
G
Giannakoulas
Vasilis
V
Kamperidis
Emmanouela G
EG
Dalamanga
Efthalia
E
Damvopoulou
Despina G
DG
Parcharidou
Theodoros D
TD
Karamitsos
Haralambos I
HI
Karvounis
D002311:Cardiomyopathy, Dilated / Q000000981:diagnostic imaging* / Q000209:etiology*; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008944:Mitral Valve Insufficiency / Q000000981:diagnostic imaging* / Q000209:etiology*; D017202:Myocardial Ischemia / Q000150:complications* / Q000000981:diagnostic imaging*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index
chronic heart failure; mitral valve regurgitation; tissue Doppler imaging