О.М. Trembovetska, G.V. Knyshov, V.P. Zakharova.Left bundle-branch block impact on longitudinal displacement indices of the left ventricular walls in patients with dilated cardiomyopathy

Myocardial longitudinal motion disorder is considered a possible pathogenetic factor in the heart failure development, in particluar, in dilated cardiomyopathy. Implementation of the speckle tracking technology provides unique opportunity to study qualitative and quantitative aspects of the myocardial motion by segments.

The aim – to study the features of the left ventricular walls longitudinal displacement in patients with dilated cardiomyopathy with and without left bundle branch block.

Material and methods. Seventy patients with dilated cardiomyopathy and 35 patients without cardiac pathology have been involved into the study. Common laboratory methods of examination and complex echocardiography, including speckle-tracking echocardiography, have been carried out. Patients with dilated cardiomyopathy have been assigned into two groups, according to the stage of heart failure and occurrence of the left bundle branch block.

Results. Higher end-diastolic and end-systolic volumes, as well as lower stroke volume and ejection fraction, higher pulmonary artery hypertension, moderate mitral and tricuspid regurgitation have been noted in patients with dilated cardiomyopathy. These changes were more significant in patients with left bundle branch block. Peak values of the longitudinal displacement were demonstrated in basal segments of the left ventricle both in healthy subjects and in dilated cardiomyopathy. At the same time, the apex of the heart remains almost static.

Conclusions. The longitudinal myocardial displacement of the left ventricle was significantly less along with more heart failure signs and in patients with left bundle branch block.

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