Assessment of segmental myocardial strain is a promising and relevant direction in the diagnosis of early impairments of left ventricular (LV) contractility in children with hypertrophic cardiomyopathy (HCM). Objective of the study: to assess the indicators of segmental myocardial strain in children with HCM. Materials and methods of research: prospective, open-label, nonrandomized, controlled. 61 patients with asymmetric HCM aged 7 to 17 years (median 9 [7,6; 13,2]) underwent echocardiography according to the standard technique with the determination of segmental longitudinal, radial, circular LV myocardium in 2D speckle tracking mode. 45 (74%) children had a non-obstructive form (NF) of HCM, 16 (26%) children had an obstructive form (OF). Obstruction was detected at the level of the LV outflow tract with a pressure gradient of 30-50 mm Hg. Results: when assessing segmental myocardial strain, a decrease in longitudinal strain was found less than the normative values in the antero-septal, anterior, antero-lateral segments in children with NF HCM with a compensatory increase in strain values in the contralateral segments (inferior septal, inferior lateral and lower ). In similar segments in children with OF, there was a significant decrease in deformity, while in the contralateral segments a less pronounced compensatory increase in deformity was determined, as well as a decrease in the minimum values of strain indicators. Assessment of segmental radial and circular strain, a statistically significant predominance of indicators in all segments, except for anterolateral, in the group with NF compared to the OF HCM was determined. A decrease in strain in the antero-septal, anterior, antero-lateral segments was found, but less pronounced compared to the indicators of longitudinal strain, as well as a compensatory increase in strain in the antero-septal values in the contralateral segments (inferior septal, inferior lateral and inferior). It has been found that the assessment of global strain values widely used in clinical practice might not be optimal enough, since too many segmental strain values are discarded and averaged, which are unevenly distributed, and therefore the assessment of strain in each segment of the myocardium in children with an asymmetric form of HCM acquires important diagnostic value. Conclusion: changes in the indicators of segmental myocardial strain reflect violations of LV contractile function and are most pronounced in OF compared with NF HCM. Their study in children is important for the timely initiation of therapy and improving the prognosis of the disease.
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