cardiotomskСибирский журнал клинической и экспериментальной медициныSiberian Journal of Clinical and Experimental Medicine2713-29272713-265XTSU publishing10.29001/2073-8552-2020-35-3-79-85cardiotomsk-1045Research ArticleКЛИНИЧЕСКИЕ ИССЛЕДОВАНИЯCLINICAL STUDIESНовые возможности оценки сократимости левого желудочка методом двухмерной speckle tracking эхокардиографииNew capabilities in assessing the left ventricular contractility by two-dimensional speckle tracking echocardiographyhttps://orcid.org/0000-0002-7463-9259ОлейниковВ. Э.OleynikovV. E.

Олейников Валентин Эливич, доктор медицинских наук, профессор, заведующий кафедрой «Терапия»

440026, Пенза, ул. Красная, 40

Valentin E. Oleynikov, Dr. Sci. (Med.), Professor, Head of the Department of Therapy 

40, Krasnaya str., Penza,  440026, Russian Federation

v.oleynikov@gmail.comhttps://orcid.org/0000-0001-9040-628XСмирновЮ. Г.SmirnovYu. G.

Смирнов Юрий Геннадьевич, доктор медицинских наук, профессор, заведующий кафедрой «Математика и суперкомпьютерное моделирование»

440026, Пенза, ул. Красная, 40

Yuriy G. Smirnov, Dr. Sci. (Med.), Professor, Head of the Department of Mathematics and Supercomputer Modeling

40, Krasnaya str., Penza,  440026, Russian Federation

smirnovyug@mail.ruhttps://orcid.org/0000-0001-7545-8196ГалимскаяВ. А.GalimskayaV. A.

Галимская Вера Александровна, кандидат медицинских наук, доцент кафедры «Терапия»

440026, Пенза, ул. Красная, 40

Vera A. Galimskaya, Cand. Sci. (Med.), Associate Professor, Therapy Department

40, Krasnaya str., Penza, 440026, Russian Federation

vera-budanova@mail.ruГундаревЕ. А.GundarevE. A.

Гундарев Евгений Андреевич, аспирант кафедры «Математика и суперкомпьютерное моделирование»

440026, Пенза, ул. Красная, 40

Evgeniy  A.  Gundarev,  Post-Graduate  Student,  Department  of Mathematics and Supercomputer Modeling t'> Therapy Department

40, Krasnaya str., Penza, 440026, Russian Federation

 

psu.gun@mail.ruhttps://orcid.org/0000-0002-4932-0000БуркоН. В.BurkoN. V.

Бурко Надежда Валерьевна, кандидат медицинских наук, доцент кафедры «Терапия»

440026, Пенза, ул. Красная, 40

 

Nadezhda V. Burko, Cand. Sci. (Med.), Associate Professor, Therapy Department

40, Krasnaya str., Penza,  440026, Russian Federation

hopeful.n@mail.ruПензенский государственный университетРоссияPenza State UniversityRussian Federation2020171020203537985Copyright © Олейников В.Э., Смирнов Ю.Г., Галимская В.А., Гундарев Е.А., Бурко Н.В., 20202020Олейников В.Э., Смирнов Ю.Г., Галимская В.А., Гундарев Е.А., Бурко Н.В.Oleynikov V.E., Smirnov Y.G., Galimskaya V.A., Gundarev E.A., Burko N.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/1045

Рассматриваются причины, по которым характеристики сократимости левого желудочка (ЛЖ), в частности пиковые показатели глобальной продольной деформации (GLS), полученные с помощью 2D спекл-эхокардиографии (ЭхоКГ), не получили широкого распространения в клинической практике. Проанализированы новые показатели, предложенные для оценки сократительной функции ЛЖ на основе продольной деформации, с учетом вклада отдельных сегментов. Показано, что перспективным направлением изучения контрактильной функции ЛЖ является определение показателей миокардиальной работы, характеризующей взаимосвязь между сократительной и насосной функцией. Представлен анализ постсистолического индекса деформации (Post systolic Strain Index – PSI), клиническое применение которого нашло отражение в работах по изучению жизнеспособного миокарда в условиях ишемии и для оценки эффективности ресинхронизирующей терапии (СRT).

This work reviews the reasons why the characteristics of left ventricular (LV) contractility, in particular, and 2D speckle echocardiography-based peak rates of global longitudinal strain (GLS), are not widely used in clinical practice. Authors present the analysis of new indicators proposed for the assessment ofLVcontractile function based on longitudinal strain taking into account the involvement of individual segments. The authors show that the assessment of myocardial work indicators characterizing the relationships between contractile and pump functions is a promising approach for the study ofLVcontractile function. The analysis of postsystolic strain index (PSI) is presented to illustrate its clinical implementation in the studies of viable myocardium in ischemic conditions and evaluating the effectiveness of cardiac resynchronization therapy (CRT).

глобальная продольня деформациясегментарная продольная деформация2D спекл-трекингэхокардиографиямиокардиальная работапостсистолическое сокращение миокардаglobal longitudinal strainsegmental longitudinal strain2D speckle trackingechocardiographymyocardial workpost-systolic myocardial shorteningReferencesFabiani I., Pugliese N.R., Santini V., Conte L., Bello V. Speckle-tracking imaging, principles and clinical applications: A review for clinical cardiologists. Intech. Open. 2016:104. DOI: 10.5772/64261.Fabiani I., Pugliese N.R., Santini V., Conte L., Bello V. Speckle-tracking imaging, principles and clinical applications: A review for clinical cardiologists. Intech. Open. 2016:104. DOI: 10.5772/64261.Baicu C.F., Zile M.R., Aurigemma G.P., Gaasch W.H. Left ventricular systolic performance, function, and contractility in patients with diastolic heart failure. Circulation. 2005;111:2306–2312. DOI: 10.1161/01. CIR.0000164273.57823.26.Baicu C.F., Zile M.R., Aurigemma G.P., Gaasch W.H. Left ventricular systolic performance, function, and contractility in patients with diastolic heart failure. Circulation. 2005;111:2306–2312. DOI: 10.1161/01. CIR.0000164273.57823.26.Owan T.E., Hodge D.O., Herges R.M., Jacobsen S.J., Roger V.L., Redfield M.M. Trends in prevalence and outcome of heart failure with preserved ejection fraction. N. Engl. J. Med. 2006;355:251–259. DOI: 10.1056/NEJMoa052256.Owan T.E., Hodge D.O., Herges R.M., Jacobsen S.J., Roger V.L., Redfield M.M. Trends in prevalence and outcome of heart failure with preserved ejection fraction. N. Engl. J. Med. 2006;355:251–259. DOI: 10.1056/NEJMoa052256.Redfield M.M., Jacobsen S.J., Burnett J.C. Jr., Mahoney D.W., Bailey K.R., Rodeheffer R.J. Burden of systolic and diastolic ventricular dysfunction in the community: Appreciating the scope of the heart failure epidemic. JAMA. 2003;289(2):194–202. DOI: 10.1001/jama.289.2.194.Redfield M.M., Jacobsen S.J., Burnett J.C. Jr., Mahoney D.W., Bailey K.R., Rodeheffer R.J. Burden of systolic and diastolic ventricular dysfunction in the community: Appreciating the scope of the heart failure epidemic. JAMA. 2003;289(2):194–202. DOI: 10.1001/jama.289.2.194.Borlaug B.A., Paulus W.J. Heart failure with preserved ejection fraction: pathophysiology, diagnosis, and treatment. Eur. Heart J. 2011;32(6):670– 679. DOI: 10.1093/eurheartj/ehq426.Borlaug B.A., Paulus W.J. Heart failure with preserved ejection fraction: pathophysiology, diagnosis, and treatment. Eur. Heart J. 2011;32(6):670– 679. DOI: 10.1093/eurheartj/ehq426.Oleinikov V., Galimskaya V., Golubeva A., Kupriyanova S. Global strain of left ventricular myocardium and ejection fraction in STEMI patients. Eur. J. Heart Failure. 2018;20(S1):40.Oleinikov V., Galimskaya V., Golubeva A., Kupriyanova S. Global strain of left ventricular myocardium and ejection fraction in STEMI patients. Eur. J. Heart Failure. 2018;20(S1):40.Galimskaya V., Kupriyanova S., Dolgarev I., Golubeva A., Oleinikov V. The heart contractile function and left ventricular ejection fraction in patients with ST-segment elevation myocardial infarction. Eur. J. Prevent. Cardiology. 2018;25(2):s19.Galimskaya V., Kupriyanova S., Dolgarev I., Golubeva A., Oleinikov V. The heart contractile function and left ventricular ejection fraction in patients with ST-segment elevation myocardial infarction. Eur. J. Prevent. Cardiology. 2018;25(2):s19.Mor-Avi V., Lang R.M., Badano L.P., Belohlavek M., Cardim N.M., Derumeaux G. et al. Current and evolving echocardiographic techniques for the quantitative evaluation of cardiac mechanics: ASE/EAE consensus statement on methodology and indications endorsed by the Japanese Society of Echocardiography. J. Am. Soc. Echocardiogr. 2011;24(3):277–313. DOI: 10.1016/j.echo.2011.01.015.Mor-Avi V., Lang R.M., Badano L.P., Belohlavek M., Cardim N.M., Derumeaux G. et al. Current and evolving echocardiographic techniques for the quantitative evaluation of cardiac mechanics: ASE/EAE consensus statement on methodology and indications endorsed by the Japanese Society of Echocardiography. J. Am. Soc. Echocardiogr. 2011;24(3):277–313. DOI: 10.1016/j.echo.2011.01.015.Kvisvik B., Aagaard E.N., Mørkrid L., Røsjø H., Lyngbakken M., Smedsrud M.K. et al. Mechanical dispersion as a marker of left ventricular dysfunction and prognosis in stable coronary artery disease. Int. J. Cardiovasc. Imaging. 2019;35(7):1265–1275. DOI: 10.1007/s10554-01901583-z.Kvisvik B., Aagaard E.N., Mørkrid L., Røsjø H., Lyngbakken M., Smedsrud M.K. et al. Mechanical dispersion as a marker of left ventricular dysfunction and prognosis in stable coronary artery disease. Int. J. Cardiovasc. Imaging. 2019;35(7):1265–1275. DOI: 10.1007/s10554-01901583-z.Al Saikhan L., Park C., Hardy R., Hughes A. Prognostic implications of left ventricular strain by speckle-tracking echocardiography in the general population: A meta-analysis. Vasc. Health Risk Manag. 2019;15:229– 251. DOI: 10.2147/VHRM.S206747.Al Saikhan L., Park C., Hardy R., Hughes A. Prognostic implications of left ventricular strain by speckle-tracking echocardiography in the general population: A meta-analysis. Vasc. Health Risk Manag. 2019;15:229– 251. DOI: 10.2147/VHRM.S206747.Voigt J.U., Pedrizzetti G., Lysyansky P., Marwick T.H., Houle H., Baumann R. et al. Definitions for a common standard for 2D speckle tracking echocardiography: Consensus document of the EACVI/ASE/Industry Task Force to standardize deformation imaging. Eur. Heart J. Cardiovasc. Imaging. 2015;16(1):1–11. DOI: 10.1016/j.echo.2014.11.003.Voigt J.U., Pedrizzetti G., Lysyansky P., Marwick T.H., Houle H., Baumann R. et al. Definitions for a common standard for 2D speckle tracking echocardiography: Consensus document of the EACVI/ASE/Industry Task Force to standardize deformation imaging. Eur. Heart J. Cardiovasc. Imaging. 2015;16(1):1–11. DOI: 10.1016/j.echo.2014.11.003.Chimura M., Yamada S., Yasaka Y., Kawai H. Improvement of left ventricular function assessment by global longitudinal strain after successful percutaneous coronary intervention for chronic total occlusion. PLoS One. 2019;14(6):e0217092. DOI: 10.1371/journal.pone.0217092.Chimura M., Yamada S., Yasaka Y., Kawai H. Improvement of left ventricular function assessment by global longitudinal strain after successful percutaneous coronary intervention for chronic total occlusion. PLoS One. 2019;14(6):e0217092. DOI: 10.1371/journal.pone.0217092.Oleynikov V.E., Galimskaya V.A., Kupriyanova S.N., Burko N.V. Use of the Speckle tracking method for determining global parameters of heart contractility in healthy individuals. Methods X. 2018;5:125–135. DOI: 10.1016/j.mex.2018.01.011.Oleynikov V.E., Galimskaya V.A., Kupriyanova S.N., Burko N.V. Use of the Speckle tracking method for determining global parameters of heart contractility in healthy individuals. Methods X. 2018;5:125–135. DOI: 10.1016/j.mex.2018.01.011.Lim P., Buakhamsri A., Popovic Z.B., Greenberg N.L., Patel D., Thomas J.D. et al. Longitudinal strain delay index by speckle tracking imaging a new marker of response to cardiac resynchronization therapy. Circulation. 2008;118(11):1130–1137. DOI: 10.1161/CIRCULATIONAHA.107.750190.Lim P., Buakhamsri A., Popovic Z.B., Greenberg N.L., Patel D., Thomas J.D. et al. Longitudinal strain delay index by speckle tracking imaging a new marker of response to cardiac resynchronization therapy. Circulation. 2008;118(11):1130–1137. DOI: 10.1161/CIRCULATIONAHA.107.750190.Aurigemma G.P., Zile M.R., Gaasch W.H. Contractile behavior of the left ventricle in diastolic heart failure: with emphasis on regional systolic function. Circulation. 2006;113(2):296–304. DOI: 10.1161/CIRCULATIONAHA.104.481465.Aurigemma G.P., Zile M.R., Gaasch W.H. Contractile behavior of the left ventricle in diastolic heart failure: with emphasis on regional systolic function. Circulation. 2006;113(2):296–304. DOI: 10.1161/CIRCULATIONAHA.104.481465.Chan J., Edwards N.F.A., Khandheria B.K., Shiino K., Sabapathy S., Anderson B. et al. A new approach to assess myocardial work by non-invasive left ventricular pressure-strain relations in hypertension and dilated cardiomyopathy. Eur. Heart J. Cardiovasc. Imaging. 2019;20(1):31–39. DOI: 10.1093/ehjci/jey131.Chan J., Edwards N.F.A., Khandheria B.K., Shiino K., Sabapathy S., Anderson B. et al. A new approach to assess myocardial work by non-invasive left ventricular pressure-strain relations in hypertension and dilated cardiomyopathy. Eur. Heart J. Cardiovasc. Imaging. 2019;20(1):31–39. DOI: 10.1093/ehjci/jey131.Russell K., Eriksen M., Aaberge L., Wilhelmsen N., Skulstad H., Gjesdal O. et al. Assessment of wasted myocardial work: A novel method to quantify energy loss due to uncoordinated left ventricular contractions. Am. J. Physiol. Heart Circ. Physiol. 2013;305(7): H996–1003. DOI: 10.1152/ajpheart.00191.2013.Russell K., Eriksen M., Aaberge L., Wilhelmsen N., Skulstad H., Gjesdal O. et al. Assessment of wasted myocardial work: A novel method to quantify energy loss due to uncoordinated left ventricular contractions. Am. J. Physiol. Heart Circ. Physiol. 2013;305(7): H996–1003. DOI: 10.1152/ajpheart.00191.2013.Chung C.S., Shmuylovich L., Kovács S.J. What global diastolic function is, what it is not, and how to measure it. Am. J. Physiol. Heart Circ. Physiol. 2015;30(9):H1392–406. DOI: 10.1152/ajpheart.00436.2015.Chung C.S., Shmuylovich L., Kovács S.J. What global diastolic function is, what it is not, and how to measure it. Am. J. Physiol. Heart Circ. Physiol. 2015;30(9):H1392–406. DOI: 10.1152/ajpheart.00436.2015.Ponikowski P., Voors A.A., Anker S.D., Bueno H., Cleland J.G.F., Coats A.J.S. et al. 2016 ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure: The Task Force for the diagnosis and treatment of acute and chronic heart failure of the European Society of Cardiology (ESC) Developed with the special contribution of the Heart Failure Association (HFA) of the ESC. Eur. Heart J. 2016;37(27):2129– 2200. DOI: 10.1093/eurheartj/ehw128.Ponikowski P., Voors A.A., Anker S.D., Bueno H., Cleland J.G.F., Coats A.J.S. et al. 2016 ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure: The Task Force for the diagnosis and treatment of acute and chronic heart failure of the European Society of Cardiology (ESC) Developed with the special contribution of the Heart Failure Association (HFA) of the ESC. Eur. Heart J. 2016;37(27):2129– 2200. DOI: 10.1093/eurheartj/ehw128.Scheffer M.G., van Dessel P.F., van Gelder B.M., Sutherland G.R., van Hemel N.M. Peak longitudinal strain delay is superior to TDI in the selection of patients for resynchronisation therapy. Neth. Heart J. 2010;18(12):574–582. DOI: 10.1007/s12471-010-0838-6.Scheffer M.G., van Dessel P.F., van Gelder B.M., Sutherland G.R., van Hemel N.M. Peak longitudinal strain delay is superior to TDI in the selection of patients for resynchronisation therapy. Neth. Heart J. 2010;18(12):574–582. DOI: 10.1007/s12471-010-0838-6.Ozawa K., Funabashi N., Nishi T., Takahara M., Fujimoto Y., Kamata T. et al. Differentiation of infarcted, ischemic, and non-ischemic LV myocardium using post-systolic strain index assessed by resting two-dimensional speckle tracking transthoracic echocardiography. Int. J. Cardiol. 2016;219:308–311. DOI: 10.1016/j.ijcard.2016.06.007.Ozawa K., Funabashi N., Nishi T., Takahara M., Fujimoto Y., Kamata T. et al. Differentiation of infarcted, ischemic, and non-ischemic LV myocardium using post-systolic strain index assessed by resting two-dimensional speckle tracking transthoracic echocardiography. Int. J. Cardiol. 2016;219:308–311. DOI: 10.1016/j.ijcard.2016.06.007.Ozawa K., Funabashi N., Nishi T., Takahara M., Fujimoto Y., Kamata T. et al. Resting multilayer 2D speckle-tracking TTE for detection of ischemic segments confirmed by invasive FFR part-2, using post-systolic-strain-index and time from aortic-valve-closure to regional peak longitudinal-strain. Int. J. Cardiol. 2016;217:149–155. DOI: 10.1016/j.ijcard.2016.04.153.Ozawa K., Funabashi N., Nishi T., Takahara M., Fujimoto Y., Kamata T. et al. Resting multilayer 2D speckle-tracking TTE for detection of ischemic segments confirmed by invasive FFR part-2, using post-systolic-strain-index and time from aortic-valve-closure to regional peak longitudinal-strain. Int. J. Cardiol. 2016;217:149–155. DOI: 10.1016/j.ijcard.2016.04.153.Celutkiene J., Sutherland G.R., Laucevicius A., Zakarkaite D., Rudys A., Grabauskiene V. Is post-systolic motion the optimal ultrasound parameter to detect induced ischaemia during dobutamine stress echocardiography? Eur. Heart J. 2004;25(11):932–942. DOI: 10.1016/j.ehj.2004.04.005.Celutkiene J., Sutherland G.R., Laucevicius A., Zakarkaite D., Rudys A., Grabauskiene V. Is post-systolic motion the optimal ultrasound parameter to detect induced ischaemia during dobutamine stress echocardiography? Eur. Heart J. 2004;25(11):932–942. DOI: 10.1016/j.ehj.2004.04.005.Kukulski T., Jamal F., Herbots L., D’hooge J., Bijnens B., Hatle L. et al. Identification of acutely ischemic myocardium using ultrasonic strain measurements: A clinical study in patients undergoing coronary angioplasty. J. Am. Coll. Cardiol. 2003;41(5):810–819. DOI:10.1016/s07351097(02)02934-0.Kukulski T., Jamal F., Herbots L., D’hooge J., Bijnens B., Hatle L. et al. Identification of acutely ischemic myocardium using ultrasonic strain measurements: A clinical study in patients undergoing coronary angioplasty. J. Am. Coll. Cardiol. 2003;41(5):810–819. DOI:10.1016/s07351097(02)02934-0.Hosokawa H., Sheehan F.H., Suzuki T. Measurement of postsystolic shortening to assess viability and predict recovery of left ventricular function after acute myocardial infarction. J. Am. Coll. Cardiol. 2000;35(7):1842–1849. DOI: 10.1016/s0735-1097(00)00634-3.Hosokawa H., Sheehan F.H., Suzuki T. Measurement of postsystolic shortening to assess viability and predict recovery of left ventricular function after acute myocardial infarction. J. Am. Coll. Cardiol. 2000;35(7):1842–1849. DOI: 10.1016/s0735-1097(00)00634-3.Eek C., Grenne B., Brunvand H., Aakhus S., Endresen K., Smiseth O.A. et al. Postsystolic shortening is a strong predictor of recovery of systolic function in patients with non-ST-elevation myocardial infarction. Eur. J. Echocardiogr. 2011;12(7):483–489. DOI: 10.1093/ejechocard/jer055.Eek C., Grenne B., Brunvand H., Aakhus S., Endresen K., Smiseth O.A. et al. Postsystolic shortening is a strong predictor of recovery of systolic function in patients with non-ST-elevation myocardial infarction. Eur. J. Echocardiogr. 2011;12(7):483–489. DOI: 10.1093/ejechocard/jer055.Takayama M., Norris R.M., Brown M.A., Armiger L.C., Rivers J.T., White H.D. Postsystolic shortening of acutely ischemic canine myocardium predicts early and late recovery of function after coronary artery reperfusion. Circulation. 1988;78(4):994–1007. DOI: 10.1161/01.cir.78.4.994.Takayama M., Norris R.M., Brown M.A., Armiger L.C., Rivers J.T., White H.D. Postsystolic shortening of acutely ischemic canine myocardium predicts early and late recovery of function after coronary artery reperfusion. Circulation. 1988;78(4):994–1007. DOI: 10.1161/01.cir.78.4.994.Skulstad H., Edvardsen T., Urheim S., Rabben S.I., Stugaard M., Lyseggen E. et al. Postsystolicshortening in ischemic myocardium. Active contraction or passive recoil? Circulation. 2002;106(6):718–724. DOI: 10.1161/01.CIR.0000024102.55150.Skulstad H., Edvardsen T., Urheim S., Rabben S.I., Stugaard M., Lyseggen E. et al. Postsystolicshortening in ischemic myocardium. Active contraction or passive recoil? Circulation. 2002;106(6):718–724. DOI: 10.1161/01.CIR.0000024102.55150.Brainin P., Skaarup K.G., Iversen A.Z., Jorgensen P.G., Platz E., Jensen J.S. et al. Post-systolic shortening predicts heart failure following acute coronary syndrome. Int. J. Cardiology. 2019;276:191–197. DOI: 10.1016/j.ijcard.2018.11.106.Brainin P., Skaarup K.G., Iversen A.Z., Jorgensen P.G., Platz E., Jensen J.S. et al. Post-systolic shortening predicts heart failure following acute coronary syndrome. Int. J. Cardiology. 2019;276:191–197. DOI: 10.1016/j.ijcard.2018.11.106.Lim P., Mitchell-Heggs L., Buakhamsri A., Thomas J.D., Grimm R.A. Impact of left ventricular size on tissue Doppler and longitudinal strain by speckle tracking for assessing wall motion and mechanical dyssynchrony in candidates for cardiac resynchronization therapy. J. Am. Soc. Echocardiogr. 2009;22(6):695–701. DOI: 10.1016/j.echo.2009.04.015.Lim P., Mitchell-Heggs L., Buakhamsri A., Thomas J.D., Grimm R.A. Impact of left ventricular size on tissue Doppler and longitudinal strain by speckle tracking for assessing wall motion and mechanical dyssynchrony in candidates for cardiac resynchronization therapy. J. Am. Soc. Echocardiogr. 2009;22(6):695–701. DOI: 10.1016/j.echo.2009.04.015.Chung E.S., Leon A.R., Tavazzi L., Sun J.P., Nihoyannopoulos P., Merlino J. et al. Results of the predictors of response to CRT (Prospect) trial. Circulation. 2008;117(20):2608–2616. DOI: 10.1161/CIRCULATIONAHA.107.743120.Chung E.S., Leon A.R., Tavazzi L., Sun J.P., Nihoyannopoulos P., Merlino J. et al. Results of the predictors of response to CRT (Prospect) trial. Circulation. 2008;117(20):2608–2616. DOI: 10.1161/CIRCULATIONAHA.107.743120.Boe E., Skulstad H., Smiseth O.A. Myocardial work by echocardiography: a novel method ready for clinical testing. Eur. Heart J. Cardiovasc. Imaging. 2019;20(1):18–20. DOI: 10.1093/ehjci/jey156.Boe E., Skulstad H., Smiseth O.A. Myocardial work by echocardiography: a novel method ready for clinical testing. Eur. Heart J. Cardiovasc. Imaging. 2019;20(1):18–20. DOI: 10.1093/ehjci/jey156.Boe E., Smiseth O.A., Storsten P., Andersen O.S., Aalen J., Eriksen M. et al. Left ventricular end-systolic volume is a more sensitive marker of acute response to cardiac resynchronization therapy than contractility indices: insights from an experimental study. Europace. 2019;21(2):347–355. DOI: 10.1093/europace/euy221.Boe E., Smiseth O.A., Storsten P., Andersen O.S., Aalen J., Eriksen M. et al. Left ventricular end-systolic volume is a more sensitive marker of acute response to cardiac resynchronization therapy than contractility indices: insights from an experimental study. Europace. 2019;21(2):347–355. DOI: 10.1093/europace/euy221.Suga H., Sagawa K. Instantaneous pressure-volume relationships and their ratio in the excised, supported canine left ventricle. Cir. Res. 1974;35(1):117–126. DOI: 10.1161/01.res.35.1.117.Suga H., Sagawa K. Instantaneous pressure-volume relationships and their ratio in the excised, supported canine left ventricle. Cir. Res. 1974;35(1):117–126. DOI: 10.1161/01.res.35.1.117.Foëx P., Leone B.J. Pressure-volume loops: A dynamic approach to the assessment of ventricular function. J. Cardiothorac. Vasc. Anesth. 1994;8(1):84–96. DOI: 10.1016/1053-0770(94)90020-5.Foëx P., Leone B.J. Pressure-volume loops: A dynamic approach to the assessment of ventricular function. J. Cardiothorac. Vasc. Anesth. 1994;8(1):84–96. DOI: 10.1016/1053-0770(94)90020-5.Russell K., Eriksen M., Aaberge L., Wilhelmsen N., Skulstad H., Remme E.W. et al. A novel clinical method for quantification of regional left ventricular pressure–strain loop area: A non-invasive index of myocardial work. Eur. Heart J. 2012;33(6):724–733. DOI: 10.1093/eurheartj/ehs016.Russell K., Eriksen M., Aaberge L., Wilhelmsen N., Skulstad H., Remme E.W. et al. A novel clinical method for quantification of regional left ventricular pressure–strain loop area: A non-invasive index of myocardial work. Eur. Heart J. 2012;33(6):724–733. DOI: 10.1093/eurheartj/ehs016.Manganaro R., Marchetta S., Dulgheru R., Ilardi F., Sugimoto T., Robinet S. et al. Echocardiographic reference ranges for normal non-invasive myocardial work indices: results from the EACVI NORRE study. Eur. Heart J.Cardiovasc. Imaging. 2018;20(5):582–590. DOI: 10.1093/ehjci/jey188.Manganaro R., Marchetta S., Dulgheru R., Ilardi F., Sugimoto T., Robinet S. et al. Echocardiographic reference ranges for normal non-invasive myocardial work indices: results from the EACVI NORRE study. Eur. Heart J.Cardiovasc. Imaging. 2018;20(5):582–590. DOI: 10.1093/ehjci/jey188.Galli E., Hubert A., Le Rolle V., Hernandez A., Smiseth O.A., Mabo P. et al. Myocardial constructive work and cardiac mortality in resynchronization therapy candidates. Am. Heart J. 2019;212:53–63. DOI: 10.1016/j.ahj.2019.02.008.Galli E., Hubert A., Le Rolle V., Hernandez A., Smiseth O.A., Mabo P. et al. Myocardial constructive work and cardiac mortality in resynchronization therapy candidates. Am. Heart J. 2019;212:53–63. DOI: 10.1016/j.ahj.2019.02.008.Galli E., Leclercq C., Fournet M., Hubert A., Bernard A., Smiseth O.A. et al. Value of myocardial work estimation in the prediction of response to cardiac resynchronization therapy. J. Am. Soc. Echocardiogr. 2018;31(2):220–230. DOI:10.1016/j.echo.2017.10.009.Galli E., Leclercq C., Fournet M., Hubert A., Bernard A., Smiseth O.A. et al. Value of myocardial work estimation in the prediction of response to cardiac resynchronization therapy. J. Am. Soc. Echocardiogr. 2018;31(2):220–230. DOI:10.1016/j.echo.2017.10.009.Van der Bijl P., Vo N.M., Kostyukevich M.V., Mertens B., Marsan N.A., Delgado V. et al. Prognostic implications of global, left ventricular myocardial work efficiency before cardiac resynchronization therapy. Eur. Heart J.Cardiovasc. Imaging. 2019;20(12):1388–1394. DOI: 10.1093/ ehjci/jez095.Van der Bijl P., Vo N.M., Kostyukevich M.V., Mertens B., Marsan N.A., Delgado V. et al. Prognostic implications of global, left ventricular myocardial work efficiency before cardiac resynchronization therapy. Eur. Heart J.Cardiovasc. Imaging. 2019;20(12):1388–1394. DOI: 10.1093/ ehjci/jez095.Manganaro R., Marchetta S., Dulgheru R., Sugimoto T., Tsugu T., Ilardi F. et al. Correlation between non-invasive myocardial work indices and main parameters of systolic and diastolic function: results from the EACVI NORRE study. Eur. Heart J.Cardiovasc. Imaging. 2020;21(5):533–541. DOI: 10.1093/ehjci/jez203.Manganaro R., Marchetta S., Dulgheru R., Sugimoto T., Tsugu T., Ilardi F. et al. Correlation between non-invasive myocardial work indices and main parameters of systolic and diastolic function: results from the EACVI NORRE study. Eur. Heart J.Cardiovasc. Imaging. 2020;21(5):533–541. DOI: 10.1093/ehjci/jez203.Boe E., Russell K., Eek C., Eriksen M., Remme E.W., Smiseth O.A. et al. Non-invasive myocardial work index identifies acute coronary occlusion in patients with non-ST-segment elevation-acute coronary syndrome. Eur. Heart J. Cardiovasc. Imaging. 2015;16(1):1247–1255. DOI: 10.1093/ehjci/jev078.Boe E., Russell K., Eek C., Eriksen M., Remme E.W., Smiseth O.A. et al. Non-invasive myocardial work index identifies acute coronary occlusion in patients with non-ST-segment elevation-acute coronary syndrome. Eur. Heart J. Cardiovasc. Imaging. 2015;16(1):1247–1255. DOI: 10.1093/ehjci/jev078.Mahdiui E.M., van der Bij P., Abou R., Ajmone M.N., Delgado V., Вах J.J. Global left ventricular myocardial work efficiency in healthy individuals and patients with cardiovascular disease. J. Am. Soc. Echocardiogr. 2019;32(9):1120–1127. DOI: 10.1016/j.echo.2019.05.002.Mahdiui E.M., van der Bij P., Abou R., Ajmone M.N., Delgado V., Вах J.J. Global left ventricular myocardial work efficiency in healthy individuals and patients with cardiovascular disease. J. Am. Soc. Echocardiogr. 2019;32(9):1120–1127. DOI: 10.1016/j.echo.2019.05.002.

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