cardiotomskСибирский журнал клинической и экспериментальной медициныSiberian Journal of Clinical and Experimental Medicine2713-29272713-265XTSU publishing10.29001/2073-8552-2019-34-1-69-77cardiotomsk-683Research ArticleКЛИНИЧЕСКИЕ ИССЛЕДОВАНИЯCLINICAL STUDIESСОСТОЯНИЕ МИТРАЛЬНОГО КЛАПАНА ПРИ ГИПЕРТРОФИЧЕСКОЙ КАРДИОМИОПАТИИ И ЕГО РОЛЬ В РАЗВИТИИ ОБСТРУКЦИИ ВЫВОДНОГО ОТДЕЛА ЛЕВОГО ЖЕЛУДОЧКАMITRAL VALVE GEOMETRY IN HYPERTROPHIC CARDIOMYOPATHY AND ITS ROLE IN THE DEVELOPMENT OF LEFT VENTRICULAR OUTFLOW TRACT OBSTRUCTIONКаневА. Ф.KanevA. F.

аспирант отделения атеросклероза и хронической ишемической болезни сердца,

634012, Томск, ул. Киевская, 111а

Postgraduate Student, Department of Atherosclerosis and Coronary Artery Disease,

111a, Kievskaya str., Tomsk, 634012

alexkanev92@gmail.comПавлюковаЕ. Н.PavlyukovaE. N.

д-р мед. наук, профессор, ведущий научный сотрудник отделения атеросклероза и хронической ишемической болезни сердца,

634012, Томск, ул. Киевская, 111а

Dr. Sci. (Med.), Leading Researcher, Department of Atherosclerosis and Coronary Artery Disease, 

111a, Kievskaya str., Tomsk, 634012

pavlyukovaelena@yandex.ruЕвтушенкоА. В.EvtushenkoA. V.

д-р мед. наук, ведущий научный сотрудник отделения атеросклероза и хронической ишемической болезни сердца,

634012, Томск, ул. Киевская, 111а

Dr. Sci. (Med.), Leading Researcher, Department of Cardiovascular Surgery, 

111a, Kievskaya str., Tomsk, 634012

ave@cardio-tomsk.ruНаучно-исследовательский институт кардиологии, Томский национальный исследовательский медицинский центр Российской академии наукРоссияCardiology Research Institute, Tomsk National Research Medical Center, Russian Academy of SciencesRussian Federation2019220420193416977Copyright © Канев А.Ф., Павлюкова Е.Н., Евтушенко А.В., 20192019Канев А.Ф., Павлюкова Е.Н., Евтушенко А.В.Kanev A.F., Pavlyukova E.N., Evtushenko A.V.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://www.sibjcem.ru/jour/article/view/683Цель

Цель: на основе чреспищеводной трехмерной реконструкции митрального клапана (МК) изучить состояние МК у пациентов с гипертрофией левого желудочка (ГЛЖ) и выявить особенности ремоделирования МК при обструктивной форме гипертрофической кардиомиопатии (ГКМП).

Материал и методы

Материал и методы. В исследование включены 48 больных ГКМП и 15 пациентов с артериальной гипертонией (АГ) и ГЛЖ. Всем больным была выполнена стандартная эхокардиография (ЭхоКГ) и чреспищеводная трехмерная ЭхоКГ в реальном масштабе времени (3D ЧПЭхоКГ) с последующей трехмерной реконструкцией МК и количественным анализом. Количественный анализ МК включал оценку фиброзного кольца (ФК) и створок МК.

Результаты

Результаты. Установлены различия в показателях 3D модели МК между больными ГКМП и пациентами с АГ и ГЛЖ. При ГКМП, по сравнению с пациентами с АГ и ГЛЖ, наблюдается увеличение высоты ФК МК (8,00±1,72 мм vs 5,99±1,95 мм; p=0,02). Высота (r=-0,55; p=0,02) и площадь ФК МК(3D) (r=-0,30; p=0,04) коррелировали с пиковым градиентом обструкции в выводном отделе ЛЖ (ВОЛЖ). ФК МК при ГКМП характеризуется более выраженной непланарностью по сравнению с АГ и ГЛЖ (2,37±0,47 усл. ед. vs 1,73±0,62 усл. ед.; p=0,02). Скорость смещения ФК МК коррелировала с пиковым (r=0,48; p=0,002) и средним (r=0,47; p=0,01) градиентами давления в ВОЛЖ. Площади передней (ПС, 6,40±2,04 см2 vs 5,07±1,04 см2 ; p<0,05) и задней (ЗС, 6,61±2,01 см2 vs 5,27±1,23 см2 ; p=0,006) створок, общая площадь створок (13,01±3,54 см2 vs 10,34±1,82 см2 ; p=0,008) и показатель отношения площади створок к площади ФК МК (1,31±0,2 усл. ед. vs 1,15±0,09 усл. ед.; р=0,01) выше при ГКМП по сравнению с АГ и ГКМП. Выявлена связь (r=-0,45; p=0,01) длины ПС МК с величиной пикового градиента обструкции в ВОЛЖ. Угол ПС МК при ГКМП, в сравнении с АГ и ГЛЖ, менее острый (32,13±9,21° vs 24,86±4,45°; р=0,04).

Выводы

Выводы. В отличие от больных АГ с ГЛЖ при ГКМП наблюдается более выраженное ремоделирование ФК МК, проявляющееся в увеличении высоты ФК и сопровождающееся увеличением площади створок и угла ПС МК. При ГКМП площадь и скорость смещения ФК МК коррелируют с градиентом обструкции в ВОЛЖ.

Aim

Aim. To evaluate structural features of the mitral valve (MV) in patients with left ventricular hypertrophy (LVH) and to identify characteristics of MV structural remodeling in hypertrophic obstructive cardiomyopathy (HOCM) patients using three-dimensional MV quantification analysis.

Material and Methods

Material and Methods. The study included 48 patients with HOCM and 15 patients with arterial hypertension and LVH. All patients underwent standard echocardiography and real-time 3D transesophageal echocardiography, followed by MV reconstruction with quantitative analysis. Quantitative analysis of MV included assessment of the mitral annulus and cusps.

Results

Results. Differences in characteristics of three-dimensional MV model between patients with HOCM and arterial hypertension and LVH were identified. In patients with HOCM, the height of the fibrous ring of the MV was increased compared to that in patients with arterial hypertension (8.00±1.72 mm vs. 5.99±1.95 mm; p=0.02). Mitral annular height (r=-0.55; p=0.02) and area(3D) (r=-0.30; p=0.04) correlated with peak LV outflow tract (LVOT) gradient. MV nonplanarity index was higher in HOCM patients (2.37±0.47 units vs. 1.73±0.62 units; p=0.02). Mitral annular maximal velocity correlated with peak (r=0.48, p=0.002) and mean (r=0.47, p=0.01) LVOT gradients. Anterior (6.40±2.04 sm2 vs. 5.07±1.04 sm2 ; p<0.05) and posterior (6.61±2.01 см2 vs. 5.27±1.23 см2 ; p=0.006) cusp areas, total cusp area (13.01±3.54 sm2 vs. 10.34±1.82 sm2 ; p=0.008), and total cusp area to annular area ratio (1.31±0.2 units vs. 1.15±0.09 units; р=0.01) had higher values in patients with HOCM. Correlation existed between anterior leaflet length and peak LVOT gradient (r=-0.45; p=0.01). Patients with HOCM had increased anterior leaflet angle compared to patients with arterial hypertension and LVH (32.13±9.21° vs. 24.86±4.45°; р=0.04).

Conclusion

Conclusion. Compared to patients with arterial hypertension and LVH, patients with HOCM experienced more pronounced MV annular remodeling presented as an increase in the annular height, which was accompanied by an increase in the cusp areas and the anterior leaflet angle. In patients with HOCM, the annular area and the maximum mitral annular velocity correlated with LVOT gradient.

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The authors declare that there are no conflicts of interest present.