vestarВестник аритмологииJournal of Arrhythmology1561-86412658-7327НАО «Инкарт»10.35336/VA-1193vestar-1324Research ArticleОРИГИНАЛЬНЫЕ ИССЛЕДОВАНИЯORIGINAL ARTICLESСравнение эндо- и эпикардиальной левожелудочковой стимуляции: трехмерное эхокардиографическое исследованиеReal-time three-dimensional transthoracic echocardiography in quantification of left ventricular dyssynchronyhttps://orcid.org/0000-0003-2852-0684МамедоваА. И.MamedovaA. I.

Мамедова Арзу Исрафил кызы

Санкт-Петербург, ул. Аккуратова, д.2

Санкт-Петербург, Учебный пер., д.5

Arzu Mamedova

Saint-Petersburg, 2 Akkuratova str.

Saint-Petersburg, 5 Uchebniy lane

arzu.mamedovaphd@gmail.comhttps://orcid.org/0000-0002-5304-8003ПриходькоН. А.Prihod’koN. A.

Санкт-Петербург, ул. Аккуратова, д.2

Saint-Petersburg, 2 Akkuratova str.

https://orcid.org/0000-0002-8651-7777ЛюбимцеваТ. А.LubimcevaT. A.

Санкт-Петербург, ул. Аккуратова, д.2

Saint-Petersburg, 2 Akkuratova str.

КозленокА. В.KozlenokA. V.

Санкт-Петербург, ул. Аккуратова, д.2

Saint-Petersburg, 2 Akkuratova str.

https://orcid.org/0000-0002-2334-1663ЛебедевД. С.LebedevD. S.

Санкт-Петербург, ул. Аккуратова, д.2

Saint-Petersburg, 2 Akkuratova str.

ФГБУ «НМИЦ им. В.А.Алмазова» МЗ РФ; СПб ГБУЗ «ГМПБ№2»РоссияFSBI «Almazov NMRC» of the MH RF; Saint-Petersburg Institution of Healthcare «City Hospital №2»Russian FederationФГБУ «НМИЦ им. В.А.Алмазова» МЗ РФРоссияFSBI «Almazov NMRC» of the MH RFRussian Federation202423012024311513Copyright © Мамедова А.И., Приходько Н.А., Любимцева Т.А., Козленок А.В., Лебедев Д.С., 20242024Мамедова А.И., Приходько Н.А., Любимцева Т.А., Козленок А.В., Лебедев Д.С.Mamedova A.I., Prihod’ko N.A., Lubimceva T.A., Kozlenok A.V., Lebedev D.S.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://vestar.elpub.ru/jour/article/view/1324Цель

Цель. Сравнение эндокардиальной и эпикардиальной левожелудочковой (ЛЖ) стимуляции при помощи синхронизированной с электрокардиограммой (ЭКГ) трехмерной эхокардиографии в режиме реального времени (3Д-ЭхоКГ).

Материал и методы исследования. Экспериментальное интраоперационное исследование, в которое включено 12 пациентов с медикаментозно компенсированной хронической сердечной недостаточностью II-IV класса и фракцией выброса менее 35%, наличием полной блокады левой ножки пучка Гиса и длительностью комплекса QRS более 150 мс, у которых изучены результаты стимуляции в 88 точках. В рамках имплантации устройства сердечной ресинхронизирующей терапии выполнялась изолированная левожелудочковая стимуляция в сопоставленных под флюорографическим контролем оппозитных точках с помощью эпикардиального квадриполярного электрода, заведенного в ветви коронарного синуса и с помощью эндокардиального временного электрода. Всего получено 44 эндокардиальных и 44 эпикардиальных точек. Средний возраст пациентов составил 68,5 [63;73,5] лет, 83% мужчин (n=10). На этапе включения выполнены 12-канальная ЭКГ, эхокардиография, тест шестиминутной ходьбы. Магнитно-резонансная томография и коронарная ангиография проводились по показаниям. У 50% пациентов была (n=6) хроническая сердечная недостаточность ишемического генеза, у 50% - неишемического (преимущественно, дилатационная кардиомиопатия). ЭКГ контроль выполнялся с помощью электрофизиологической системы LabSystem Pro EP Recording System (Bard Electrophysiology, США). В каждой точке измеряли длительность стимулированного комплекса QRS, выполняли чреспищеводную трехмерную эхокардиография в режиме реального времени (3Д-ЭхоКГ) с фиксацией и записью материалов для последующей обработки в программных пакетах TomTec и Philips Qlab 3DQ Advanced (Philips Medical Systems, США).

Результаты

Результаты. Полуколичественные параметрические трехмерные индексы сегментарной экскурсии и сократимости миокарда, полученные с помощью 3Д-ЭхоКГ, такие, как ExcAvg (p<0,001), ExcMax (p=0,001), ExcMin (p<0,001), фракция выброса трехмерной модели левого желудочка, (p=0,003), значимо различались и показывали преимущество эндокардиальной стимуляции. Индекс диссинхронии Tmsv-6SD в точке 2 стимуляции был значимо меньше (р=0,03) при эндокардиальной стимуляции. По аналогичным индексам диссинхронии, но для 16 и 12-сегментной модели (SDI-16, Tmsv-12SD) (при р=0,06) выявлена лишь тенденция к значимому различию. Длительность QRS при эндокардиальной стимуляции составила 190 [179;215] мс и была значимо меньше, чем при эпикардиальной - 218 [197;246] (p=0,0008). Полуколичественные и количественные параметры, полученные с помощью 3Д-ЭхоКГ демонстрируют преимущество эндокардиальной стимуляции с точки зрения улучшения сократительной способности миокарда, уменьшения степени диссинхронии, уменьшения объемов ЛЖ даже в рамках интраоперационного исследования.

Выводы

Выводы. Эндокардиальная стимуляция имеет ряд преимуществ, с точки зрения улучшения сократительной способности миокарда, уменьшения степени механической диссинхронии и объемов ЛЖ, продемонстрированных с помощью 3Д-ЭхоКГ параметров оценки глобальной и сегментарной сократимости, внутрижелудочковой диссинхронии и ЭКГ критериев в рамках интраоперационного исследования. 3Д-ЭхоКГ позволяет более точно и воспроизводимо отражать зону поздней активации миокарда, а методика эндокардиальной ЛЖ стимуляции имеет преимущество с точки зрения большей маневренности позиционирования стимулирующего полюса ЛЖ электрода в целевую зону.

Aim

Aim. To compare endocardial and epicardial left ventricular (LV) pacing using real-time electrocardiography (ECG)-synchronized three-dimensional echocardiography (3DE).

Methods

Methods. Experimental intraoperative study included 88 points obtained from 12 patients with compensated heart failure of II-IV functional class NYHA (LV ejection fraction < 35%) and cardiac resynchronization therapy indications - ECG pattern of complete left bundle branch block (LBBB) and QRS complex duration > 150 ms. During isolated LV pacing as part of cardiac resynchronization therapy implantation procedure endocardial and epicardial stimulation points matched under fluoroscopic control using quadripolar coronary sinus leads and endocardial electrodes for temporary pacing were obtained. The overall number of corresponding pacing sites included 44 endocardial and 44 epicardial stimulation positions. The mean age of patients was 68.5 [63; 73.5] years, 83% males (n=10). Before study enrollment, 12-channel ECG, echocardiography, and a six-minute walk test were performed for all participants along with cardiac magnetic resonance imaging and control coronary angiography if indicated. The prevalence of coronary heart disease was 50% (n=6) while dilated cardiomyopathy was the most common etiology of chronic heart failure in other cases. Intraoperative ECG with estimation of paced QRS complex morphology at each point was registered via LabSystem Pro Electrophysiological Recording System (Bard Electrophysiology, USA). 3DE was performed using TomTec and Philips Qlab 3DQ Advanced software (Philips Medical Systems, USA).

Results

Results. Three-dimensional parametric imaging of LV regional segmental excursion and myocardial contractility using 3DE revealed statistically significant difference in semi-quantative parameters such as ExcAvg (p<0.001), ExcMax (p=0.001), ExcMin (p<0.001) and LV ejection fraction based on 3D modelling (p=0.003) while endocardial pacing was more beneficial. During the course of endocardial stimulation, the 3DE dyssynchrony index estimated at the 2nd stimulation site was also significantly lower (p=0.03). Identical dyssynchrony parameters valid for the 16 and 12-segment 3D models (SDI-16, Tmsv-12SD) (at p=0.06) demonstrated only a tendency for significant difference. The duration of QRS complex at the time of endocardial pacing was significantly shorter (<190 [179;215] ms) (p=0.0008). Semi-quantitative and quantitative 3DE parameters showed the benefit of endocardial pacing resulting in cardiac contractility improvement with less dyssynchrony and LV volume reducing during intraoperative period.

Conclusion

Conclusion. Endocardial pacing has potential benefit over the epicardial pacing represented by intraoperative dynamics of LV global and local contractility, intraventricular dyssynchrony estimated by 3DE and also ECG criteria. 3DE is helpful in more precise and reproducibile determing of late activation zone for target LV lead placement that is more manoeuvrable in case of endocardial stimulation.

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