Strain and strain rate imaging by echocardiography - basic concepts and clinical applicability

Michael Dandel, Hans Lehmkuhl, Christoph Knosalla, Nino Suramelashvili, Roland Hetzer, Michael Dandel, Hans Lehmkuhl, Christoph Knosalla, Nino Suramelashvili, Roland Hetzer

Abstract

Echocardiographic strain and strain-rate imaging (deformation imaging) is a new non-invasive method for assessment of myocardial function. Due to its ability to differentiate between active and passive movement of myocardial segments, to quantify intraventricular dyssynchrony and to evaluate components of myocardial function, such as longitudinal myocardial shortening, that are not visually assessable, it allows comprehensive assessment of myocardial function and the spectrum of potential clinical applications is very wide. The high sensitivity of both tissue Doppler imaging (TDI) derived and two dimensional (2D) speckle tracking derived myocardial deformation (strain and strain rate) data for the early detection of myocardial dysfunction recommend these new non-invasive diagnostic methods for extensive clinical use. In addition to early detection and quantification of myocardial dysfunction of different etiologies, assessment of myocardial viability, detection of acute allograft rejection and early detection of allograft vasculopathy after heart transplantation, strain and strain rate data are helpful for therapeutic decisions and also useful for follow-up evaluations of therapeutic results in cardiology and cardiac surgery. Strain and strain rate data also provide valuable prognostic information, especially prediction of future reverse remodelling after left ventricular restoration surgery or after cardiac resynchronization therapy and prediction of short and median-term outcome without transplantation or ventricular assist device implantation of patients referred for heart transplantation.The Review explains the fundamental concepts of deformation imaging, describes in a comparative manner the two major deformation imaging methods (TDI-derived and speckle tracking 2D-strain derived) and discusses the clinical applicability of these new echocardiographic tools, which recently have become a subject of great interest for clinicians.

Keywords: Strain imaging; diagnosis; echocardiography; myocardial contraction; prognosis..

Figures

Fig. (1)
Fig. (1)
Tissue Doppler derived left ventricular wall motion velocity (panel A) and myocardial strain (panel B) images from a heart transplanted patient with normal cardiac function and no evidence of coronary artery disease. The velocity and strain curves were obtained in apical long axes views during the same cardiac cycle from the same two myocardial regions (posterior-basal and apical). Because of the velocity gradient which normally exists between the basal and apical LV regions (highest at the base and lowest in apical regions), the assessment of wall motion velocity is not useful for detection of regional differences in contractile function. Thus, as shown by the yellow curves, despite the very low wall motion velocity in the apical region (panel A), the longitudinal myocardial shortening in this region can be even higher than in basal regions (panel B).
Fig. (2)
Fig. (2)
Speckle-tracking 2D-strain imaging (apical long axis view) in a heart transplanted patient with normal LV function and no angiographic evidence of coronary artery disease. The same echocardiographic loop was used for evaluation of myocardial displacement and longitudinal deformation (strain) in the 6 visible LV wall segments. The images in panel A and B show that myocardial displacement can be misleading by suggesting regional differences in contractile function, although, as shown in panel C, myocardial deformation analysis (strain imaging) does not reveal relevant regional differences in myocardial longitudinal shortening.
Fig. (3)
Fig. (3)
Longitudinal global strain (dotted white curve) and regional longitudinal strain curves (distinctively colored curves for 6 left ventricular wall segments) obtained from apical 4-chamber views by speckle-tracking 2D-strain imaging in a patient with Takotsubo cardiomyopathy. Although during catecholamine induced severe LV dysfunction with apical ballooning (A) the apex appeared nearly akinetic (no visible relevant inward movement) the longitudinal strain curves showed the same uniform longitudinal shortening as after recovery (B), when also visually no regional wall motions were detectable. Thus, the visual analysis of inward movement used in conventional echocardiographic examinations can be misleading in the evaluation of regional myocardial contraction because it can not exclude the existence of longitudinal shortening (not visible with the naked eye) in the apparently akinetic region [cf. Dandel et al. International Journal of Cardiology 2008].
Fig. (4)
Fig. (4)
Longitudinal strain before and after cardiac surgery (coronary bypass and mitral valve reconstruction) in a patient with coronary artery disease associated with severe mitral regurgitation. Global strain (white dotted line) increased from less than 3% preoperatively (A and C) to 11% after surgery (B and D). There was also a relevant improvement in the synchrony and synergy of regional systolic longitudinal shortening revealed by the more uniform amplitude and time course of the differently colored regional strain curves. [Knosalla C, Dandel M et al., Annual Meeting of the German Society for Thoracic and Vascular Surgery 2007].
Fig. (5)
Fig. (5)
Left ventricular longitudinal strain images obtained from the 4-chamber view of a patient with LV apical aneurysma after myocardial infarction before (panel A) and after (panel B) surgical LV restoration. Less systolic asynchrony (more uniform contraction), more uniform relaxation and improvement of contractile function in apical and basal lateral regions were the most evident postoperative changes detectable by 2D strain imaging. [Knosalla C, Dandel M, et al. Journal of Heart Lung Transplant 2008; 27: S186].
Fig. (6)
Fig. (6)
Left ventricular longitudinal strain (shortening) and strain rate (velocity of shortening) images obtained from apical 2-chamber views before (A and C, respectively) and after surgical ventricular restoration (B and D, respectively) in a patient with initially severe LV dysfunction after apical myocardial infarction. Panels B and D show more uniform shortening (amplitude and velocity, respectively) after surgery. [Knosalla C, Dandel M et al., Annual Meeting of the German Society for Thoracic and Vascular Surgery 2007].
Fig. (7)
Fig. (7)
Left ventricular strain changes during symptomatic, biopsy-proven acute rejection (mixed cellular and vascular rejection). Radial (A and B), circumferential (C and D) and longitudinal (E and F) global strain decreased during rejection by 24%, 50% and 38%, respectively, without changes in synchrony and synergy of myocardial contraction. [Dandel et al. 2007, oral abstract, AHA Scientific Session].
Fig. (8)
Fig. (8)
Left ventricular radial (A and B) and circumferential (C and D) strain rate changes in an asymptomatic patient with mild acute rejection (ISHLT grade 1). The peak systolic and diastolic strain rates (dotted yellow arrows) were higher in rejection-free state (A and C) and lower during rejection (B and D). Strain rate reduction was more evident in diastole than in systole. [Dandel et al. 2007, oral abstract, AHA Scientific Sessions].
Fig. (9)
Fig. (9)
Left ventricular strain and strain rate images in heart transplant recipients with focal stenoses of coronary arteries. A and B: Circumferential strain and strain rate in a patient with stenosis of the right coronary artery. C and D: Longitudinal strain and strain rate in a patient with stenosis of the left anterior descending coronary artery. [Dandel et al. JHLT 2008; 27(2): S95-96].
Fig. (10)
Fig. (10)
Time course of 2D-strain images recorded during reduction of the LVAD (Type Incor) rate in a patient with idiopathic dilated cardiomyopathy who showed relevant myocardial recovery during mechanical unloading. After LVAD implantation, the left ventricular global strain values were low and regional strain curves showed important dyssynchrony and dyssynergy (A and B). One month later global strain values were several times higher and regional strain curves indicated uniform circumferential shortening and radial thickening (C and D, respectively). [Dandel et al. 2007, oral abstract, AHA Scientific Sessions].

References

    1. Sheehan FH. Quantitative evaluation of regional left ventricular systolic function. In: Otto CM, editor. The Practice of Clinical Echocardiography. Philadelphia: WB Saunders Company; 2002. pp. 65–87.
    1. Perk G, Tunick PA, Kronzon I. Non-Doppler two-dimensional strain imaging by echocardiography – from technical considerations to clinical applications. J Am Soc Echocardiogr. 2007;49(19):1903–14.
    1. Sutherland G, Steward M, Groundstroen K, et al. Color Doppler myocardial imaging: a new technique for the assessment of myocardial function. J Am Soc Echocardiogr. 1994;7:441–58.
    1. Heimdal A, Stoylen A, Torp H, Skjaerpe T. Real time strain rate imaging of the left verntricle by ultrasound. J Am Soc Echocardiogr. 1998;11:1013–19.
    1. Stouylen A, Heimdal A, Bjornstad K, et al. Strain rate imaging by ultrasound in the diagnosis of regional dysfunction of the left ventricle. Echocardiography. 1999;16(4):321–9.
    1. Veyrat C, Pellerin D, Larrazet F. Myocardial Doppler tissue imaging: past, present and future. Arch Mal Coeur Vaiss. 1997;90(10):1391–402.
    1. Urheim S, Edvardsen T, Torp H, et al. Myocardial strain by Doppler echocardiography: validation of a new method to quantify regional myocardial function. Circulation. 2000;102:1158–64.
    1. Waggoner AD, Bierig SM. Tissue Doppler imaging: a useful echocardiographic method for the cardiac sonographer to assess systolic and diastolic ventricular function. J Am Soc Echocardiogr. 2001;14(12):1143–52.
    1. Edvardsen T, Gerber BL, Garot J, et al. Qualitative assessment of intrinsic regional myocardial deformation by Doppler strain rate echocardiography in humans: Validation against three-dimensional tagged magnetic resonance imaging. Circulation. 2002;106:50–56.
    1. Sengupta PP, Mohan JC, Pandian NG. Tissue Doppler echocardiography: principles and applications. Indian Heart J. 2002;54(4):368–78.
    1. Yu CM, Sanderson JE, Marwick TH, Oh JK. Tissue Doppler imaging a new prognosticator for cardiovascular diseases. J Am Coll Cardiol. 2007;20(3):234–243.
    1. D’Hooge J, Heimdal A, Jamal F, et al. Regional strain and strain rate measurements by cardiac ultrasound: principles, implementation and limitations. Eur J Echocardiogr. 2000;1(3):154–70.
    1. Aurigemma GP, Douglas PS, Gaasch HW. Quantitative evaluation of left ventricular structure, wall stress and systolic function. In: Otto CM, editor. The Practice of Clinical Echocardiography. Philadelphia: WB Saunders Company; 2002. pp. 65–87.
    1. Flemming AD, Xia X, McDicken WM, et al. Myocardial velocity gradients detected by Doppler imaging. Br J Radiol. 1994;67:679–88.
    1. Uematsu M, Miyatake K, Tanaka N, et al. Myocardial velocity gradient as a new indicator of regional left ventricular contraction: detection by two-dimensional tissue Doppler imaging technique. J Am Coll Cardiol. 1995;26:217–23.
    1. Marwick TH. Measurement of strain and strain rate by echocardiography: ready for prime time? J Am Coll Cardiol. 2006;47:1313–27.
    1. Leitman M, Lysyansky P, Sidenko S, et al. Two-dimensional strain-a novel software for real time quantitative echocardiographic assessment of myocardial function. J Am Soc Echocardiogr. 2004;17:1021–29.
    1. Ingul CB, Torp H, Aase SA. Automated analyses of strain rate and strain: feasibility and clinical implications. J Am Soc Echocardiogr. 2005;18:411–18.
    1. Modesto KM, Cauduro S, Dispezieri A, et al. Two-dimensional acoustic pattern derived strain parameters closely correlate with one-dimensional tissue Doppler derived strain measurements. Eur J Echocardiogr. 2006;7:315–21.
    1. Serri K, Reant P, Lafitte M, et al. Global and regional myocardial function quantification by two-dimensional strain. J Am Coll Cardiol. 2006;47:1175–81.
    1. Reisner SA, Lysyansky P, Agmon Y, et al. Global longitudinal strain: a novel index of left ventricular systolic function. J Am Soc Echocardiogr. 2004;17:630–33.
    1. Teske AJ, De Boeck BWL, Olimulder M, et al. Echocardiographic assessment of regional right ventricular function. A head to head comparison between 2D-strain and tissue Doppler derived strain analysis. J Am Soc Echocardiogr. 2007;21(3):275–83.
    1. Behar V, Adam D, Lysyanski P, et al. Improving motion estimation by accounting for local image distorsion. Ultrasonics. 2004;43(1):57–65.
    1. Korinek J, Kjaergaard J, Sengupta PP, et al. High spatial resolution speckle tracking improves accuracy of 2-dimensional strain measurements. J Am Soc Echocardiogr. 2007;20(2):165–70.
    1. Amundsen BH, Helle-Valle T, Edvardson T, et al. Noninvasive myocardial strain measurement by a novel automated tracking system from digital image files. J Am Coll Cardiol. 2006;47:789–93.
    1. Kylmälä MM, Antila MK, Kivistö SM, et al. Tissue-Doppler strain-mapping in the assessment of the extent of chronic myocardial infarction: validation using magnetic resonance imaging. Eur J Echocardiogr. 2008;9(5):678–84.
    1. Urheim S, Edvardson T, Torp B, et al. Myocardial strain by Doppler echocardiography. Validation of a new method to quantify regional myocardial function. Circulation. 2000;102:1158–64.
    1. Wang J, Khouri DS, Thohan V, et al. Global diastolic strain rate for assessment of left ventricular relaxation and filling pressure. Circulation. 2007;115(11):1376–83.
    1. Yoneyama A, Koyama J, Tomita T, et al. Relationship of plasma brain-type natriuretic peptide levels to left ventricular longitudinal function in patients with congestive heart failure by strain Doppler imaging. Int J Cardiol. 2008;130(1):56–63.
    1. Edvardsen T, Skulstad H, Aakhus S, et al. Regional myocardial systolic function during acute myocardial ischemia assessed by strain Doppler echocardiography. J Am Coll Cardiol. 2001;37(3):726–30.
    1. Sutherland GR, Di SG, Claus J, et al. Strain and strain rate imaging: a new clinical approach to quantifying regional myocardial function. J Am Soc Echocardiogr. 2004;17:788–802.
    1. Voigt JU, Exner B, Schmiedehausen K, et al. Strain-rate imaging during dobutamin stress echocardiography provides objective evidence of inducible ischemia. Circulation. 2003;107:2120–26.
    1. Vartdal T, Brunwand H, Pettersen E, et al. Early prediction of infarct size by strain Doppler echocardiography after coronary reperfusion. J Am Coll Cardiol. 2007;49(16):1715–21.
    1. Weidemann F, Jung P, Hoyer C, et al. Assessment of contractile reserve in patients with intermediate coronary lesions: a strain imaging study validated by invasive myocardial fractional flow reserve. Eur Heart J. 2007;28(12):1425–32.
    1. Gjesdal O, Hopp E, Vartdal T, et al. Global longitudinal strain measured by two-dimensional speckle tracking is closely related to myocardial infarct size in chronic ischemic heart disease. Clin Sci (Lond) 2007;113(6):287–96.
    1. Winter R, Jussila R, Nowak J, Brodin LA. Speckle tracking echocardiography is a sensitive tool for detection of myocardial ischemia: a pilot study from the catheterization laboratory during percutaneous coronary intervention. J Am Soc Echocardiogr. 2007;20(8):974–81.
    1. Tanaka H, Oishi Y, Mizuguchi Y, et al. Three-dimensional evaluation of dobutamine-induced changes in regional myocardial deformation in ischemic myocardium using ultrasonic strain measurements: the role of circumferential shortening. J Am Soc Echocardiogr. 2007;20(11):1294–99.
    1. Qu HY, Yao GH, Sun WY. Assessment of ischemic myocardium by strain-rate imaging during adenosine stress echocardiography. Int J Cardiovasc Imaging. 2007;23(6):725–32.
    1. Liang HY, Cauduro S, Pellukka P, et al. Usefulness of two-dimensional speckle strain for evaluation of left ventricular diastolic deformation in patients with coronary artery disease. Am J Cardiol. 2006;98(12):1581–86.
    1. Dandel M, Knosalla C, Lehmkuhl H, Hetzer R. Non-Doppler two-dimensional strain imaging – clinical application. J Am Soc Echocardiogr. 2007;20(8):1119.
    1. Artis NJ, Oxborough DL, Williams G, et al. Two-dimensional strain imaging: a new echocardiographic advance with research and clinical applications. Int J Cardiol. 2008;123(3):240–8.
    1. Marciniak A, Claus P, Sutherland GR, et al. Changes in systolic left ventricular function in isolated mitral regurgitation. A strain rate imaging study. Eur Heart J. 2007;28(21):2627–36.
    1. Kepez A, Akdogan A, Sade LE, et al. Detection of subclinical cardiac involvement in systemic sclerosis by Echocardiographic stain imaging. Echocardiography. 2008;25:191–97.
    1. Hare JL, Brown JK, Marwick TH. Association of myocardial strain with left ventricular geometry and prognosis of hypertensive heart disease. Am J Cardiol. 2008;102:87–91.
    1. Donal E, De Place C, Kervio G, et al. Mitral regurgitation in dilated cardiomyopathy : value of both regional left ventricular contractility and dyssynchrony. Eur J Echocardiogr. 2009;10(1):133–8.
    1. Marciniak A, Sutherland GR, Marciniak M, et al. Myocardial deformation abnormalities in patients with aortic regurgitation: a strain rate imaging study. Eur J Echocardiogr. 2009;10(1):112–9.
    1. D’Andrea A, Stisi S, Caso P, et al. Associations between left ventricular myocardial involvement and endothelial dysfunction in systemic sclerosis: noninvasive assessment in asymptomatic patients. Echocardiography. 2007;24(6):587–97.
    1. Galderisi M, de Simone G, Inneli P, et al. Impaired inotropic response to type 2 diabetes mellitus: a strain rate imaging study. Am J Hypertens. 2007;20(5):548–55.
    1. Bellavia D, Abraham TP, Pellikka PA, et al. Detection of left ventricular systolic dysfunction in cardiac amyloidosis with strain rate echocardiography. J Am Soc Echocardiogr. 2007;20(10):1194–202.
    1. Mori K, Hayabuchi Y, Inoue M, et al. Myocardial strain imaging for early detection of cardiac involvement in patients with Duchenne’s progressive muscular dystrophy. Echocardiography. 2007;24(6):598–608.
    1. Arnold R, Goebel B, Ulmer HE, et al. An exercise tissue Doppler strain rate imaging study of diastolic myocardial dysfunction after Kawasaki syndrome in childhood. Cardiol Young. 2007;17(5):778–86.
    1. Migrino RQ, Aggarwal D, Konorev E, et al. Early detection of doxorubicin cardiomyopathy using two-dimensional strain echocardiography. Ultrasound Med Biol. 2008;34:208–14.
    1. Poulsen SH, Hjortshøj S, Korup E, et al. Strain rate and tissue tracking imaging in quantification of left ventricular systolic function in endurance and strength athletes. Scand J Med Sci Sports. 2007;17(2):148–55.
    1. D’Andrea A, De Corato G, Scarafile R, et al. Left atrial myocardial function in either physiologic or pathologic left ventricular hypertrophy: A two-dimensional speckle strain study. Br J Sports Med. 2008;42(8):696–702.
    1. Richand V, Lafitte S, Reant P, et al. An ultrasound speckle tracking (two-dimensional strain) analysis of myocardial deformation in profesional soccer players compared with healthy subjects and hypertrophic cardiomyopathy. Am J Cardiol. 2007;100(1):128–32.
    1. Saghir M, Areces M, Makan M. Strain rate imaging differentiates hypertensive cardiac hypertrophy from physiologic cardiac hypertrophy (athlete’s heart) J Am Soc Echocardiogr. 2007;20(2):151–57.
    1. Sevimli G, Gundogdu F, Aksakal E, et al. Right ventricular strain rate properties in patients with right ventricular myocardial infarction. Echocardiography. 2007;24(7):732–8.
    1. Lindquist P, Calcutteea A, Henein M. Echocardiography in the assessment of the right heart function. Eur J Echocardiogr . 2007 [Epub ahead of print]
    1. Gondi S, Dokainish H. Right ventricular tissue Doppler and strain imaging: Ready for clinical use? Echocardiogaphy. 2007;24(5):322–32.
    1. López-Candales A, Rajagopolan N, Dohi K, et al. Abnormal right ventricular myocardial strain generation in mild pulmonary hypertension. Echocardiography. 2007;24(6):615–22.
    1. Dambrauskaite V, Delcroix M, Claus P, et al. Regional right ventricular dysfunction in chronic pulmonary hypertension. J Am Soc Echocardiogr. 2007;20(10):1172–80.
    1. Huez S, Vachiéry JL, Unger P, et al. Tissue Doppler imaging evaluation of cardiac adaptation in severe pulmonary hypertension. Am J Cardiol. 2007;100(9):1473–78.
    1. Prakasa KR, Wang J, Tandri H, et al. Utility of tissue Doppler and strain echocardiography in arrhythmogenic right ventricular dysplasia/cardiomyopathy. Am J Cardiol. 2007;100:1473–78.
    1. Boettler P, Hartmann M, Watzl K, et al. Heart rate effects on strain and strain rate in healthy children. J Am Soc Echocardiogr. 2005;18:1121–3.
    1. Park TH, Nagueh SF, Khoury DS, et al. Impact of myocardial structure and function postinfarction on diastolic strain measurements: implications for assessment of myocardial viability. Am J Physiol Heart Circ Physiol. 2006;209:H724–H731.
    1. Sun JP, Niu J, Chou D, et al. Alterations of regional myocardial function in a swine model of myocardial infarction assessed by echocardiographic 2-dimensional strain imaging. J Am Soc Echocardiogr. 2007;20(5):498–504.
    1. Migrino RQ, Zhu X, Pajewski N, et al. Assessment of segmental myocardial viability using regional 2-dimensional echocardiography. J Am Soc Echocardiogr. 2007;20(4):342–51.
    1. Popovic ZB, Benjam C, Bian J, et al. Speckle-tracking echocardiography correctly identifies segmental left vetricular dysfunction induced by scarring in a rat model of myocardial infarction. Am J Physiol Heart Circ Physiol. 2007;292(6):H2809–16.
    1. Hanekom L, Cho GY, Leano R, et al. Comparison of two-dimensional speckle and tissue Doppler strain measurement during dobutamine stress echocardiography: an angiographic correlation. Eur Heart J. 2007;28(14):1765–72.
    1. Chan J, Hanekom L, Wong C, et al. Differentiation of subendocardial and transmural myocardial infarction using two-dimensional strain rate imaging to assess short and long axis function. J Am Coll Cardiol. 2006;48:2226–32.
    1. Bjork Ingul C, Rozis E, Marwick TH. Prediction of mortality using strain rate in dobutamine stress echocardiography. Circulation. 2006;112:II635.
    1. Park YH, Kang SJ, Song JK, et al. Prognostic value of longitudinal strain after primary reperfusion therapy in patients with anterior-wall acute myocardial infarction. J Am Soc Echocardiogr. 2008;21(3):262–7.
    1. Ingul CB, Stoylen A, Slordahl SA, et al. Automated analysis of myocardial deformation at dobutamine stress echocardiography: an angiography validation. J Am Coll Cardiol. 2007;49(15):1651–59.
    1. Dandel M, Lehmkuhl H, Knosalla C, Hetzer R. Left ventricular wall motion abnormality and myocardial dysfunction in stress cardiomyopathy: New pathophysiological aspects suggested by echocardiography. Int J Cardiol. 2008 [Epub ahead of print]
    1. Knosalla C, Dandel M, Kuckucka M, et al. Acute decrease of left ventricular mechanical dyssynchrony and improvement of contractile state after left ventricular restoration. Thorac Cardiovasc Surg. 2007;55:S125.
    1. Poulsen SH, Sogaard P, Nielsen-Kudsk JE, Egeblad H. Recovery of left ventricular systolic longitudinal strain after valve replacement in aortic stenosis and relation to natriuretic peptide. J Am Soc Echocardiogr. 2007;20(7):877–84.
    1. Dandel M, Hummel M, Müller J, et al. Reliability of tissue Doppler Wall motion monitoring after heart transplantation for replacement of invasive routine screenings by optimally timed cardiac biopsies and catheterizations. Circulation. 2001;104(suppl):I-184–I-191.
    1. Derumeaux G, Redonnet M, Soyer R, et al. Assessment of the progression of cardiac allograft vasculopathy by dobutamine stress echocardiography. J Heart Lung Transplant. 1998;17(3):259–67.
    1. Dandel M, Wellnhofer E, Hummel M, et al. Early detection of left ventricular dysfunction related to transplant coronary artery disease. J Heart Lung Tranplant. 2003;22:1353–64.
    1. Dandel M, Lehmkuhl H, Knosalla C, Hetzer R. Tissue Doppler imaging: Diagnostic and prognostic value. J Am Coll Cardiol. 2007;50(16):1614.
    1. Dandel M, Lehmkuhl H, Knosalla C, Hetzer R. Non-Doppler two-dimensional strain imaging for early detection of heart transplant recipients with coronary stenoses. Circulation. 2007;116(16 suppl.):II–322.
    1. Marciniak A, Eroglu E, Marciniak M, et al. The potential clinical role of strain and strain rate imaging in diagnosing acute rejection after heart transplantation. Eur J Echocardiogr. 2007;8(3):213–21.
    1. Dandel M, Wellnhofer E, Lehmkuhl H, et al. Early detection of left ventricular wall motion alterations in heart allografts with coronary artery disease: diagnostic value of tissue Doppler and two-dimensional (2D) strain echocardiography. Eur J Echocardiogr. 2006;7:S127–28.
    1. Eroglu E, D’hooge J, Sutherland GR, et al. Quantitative dobutamine stress echocardiography for the early detection of cardiac allograft vasculopathy in heart transplant recipients. Heart. 2008;94(2):e3. Epub 2007 Okt 4.
    1. Vagnini FJ, Gourin A, Antell HI, Stuckey JH. Implantation sites of cardiac pacemaker electrodes and myocardial contractility. Ann Thorac Surg. 1967;4:431–39.
    1. Bristow MR, Saxon LA, Boehmer J, et al. Cardiac-resynchronization therapy with or without an implantable defibrillator in advanced chronic heart failure. N Engl J Med. 2004;350:2140–50.
    1. Cleland JG, Daubert JC, Erdmann E, et al. The effect of cardiac resynchronization on morbidity and mortality in heart failure. N Engl J Med. 2005;352:1539–49.
    1. Lim P, Buakhamsri A, Popoviv ZB, et al. Longitudinal strain delay index by speckle tracking imaging. A new marker of response to cardiac resynchronization therapy. Circulation. 2008;118:1130–37.
    1. Teske AJ, De Boeck BM, Melman PG, et al. Echocardiographic quantification of myocardial function using tissue deformation imaging, a guide to image acquisition and analysis using tissue Doppler and speckle tracking. Cardiovasc Ultrasound. 2007;30:5–27.
    1. Friedberg MK, Silverman NH, Dubin AM, Rosenthal DN. Mechanical dyssynchrony in children with systolic dysfunction secundary to cardiomyopathy: a Doppler tissue vector velocity imaging study. J Am Soc Echocardiogr. 2007;20(6):756–63.
    1. Becker M, Franke A, Breithardt OA, et al. Impact of left ventricular lead position on the efficacy of cardiac resynchronization therapy: a two-dimensional strain echocardiography study. Heart. 2007;93(10):1197–203.
    1. Knebel F, Schattke S, Bondke H, et al. Evaluation of longitudinal and radial two-dimensional strain imaging versus Doppler tissue echocardiography in predicting long-term response to cardiac resynchronization therapy. J Am Soc Echocardiogr. 2007;20(4):335–41.
    1. Becker M, Kramann R, Franke A, et al. Impact of left ventricular lead position in cardiac resynchronization therapy on left ventricular remodeling. A circumferential strain analysis based on 2D echocardiography. Eur Heart J. 2007;28(10):1211–20.
    1. Gorcsan J 3rd, Tanabe M, Bleeker GB, et al. Combined longitudinal and radial dyssynchrony predicts ventricular response after resynchronization therapy. J Am Coll Cardiol. 2007;50(15):1476–83.
    1. Nagueh SF. Mechanical dyssynchrony in congestive heart failure: diagnostic and therapeutic implications. J Am Coll Cardiol. 2008;51(1):18–22.
    1. Yu CM, Gorcsan J 3rd, Bleeker GB, et al. Usefulness of tissue Doppler velocity and strain dyssynchrony for predicting left ventricular reverse remodeling response after cardiac resynchronization therapy. Am J Cardiol. 2007;100(8):1263–70.
    1. Arita T, Sorescu GP, Schuler BT, et al. Speckle-tracking stain echocardiography for detecting cardiac dyssynchrony in a canine model of dyssynchrony and heart failure. Am J Physiol Heart Circ Physiol. 2007;293(1):H735–42.
    1. Rappaport D, Konyukhov E, Shulman L, et al. Detection of the cardiac activation sequence by novel echocardiographic tissue tracking method. J Ultrasound Med Biol. 2007;33(6):880–93.
    1. De Boeck BWL, Kirn B, Teske AJ, et al. Three-dimensional mapping of mechanical activation patterns, contractile dyssynchrony and dyscoordination by two-dimensional strain echocardiography. Cardiovascular Ultrasound. 2008;6:22. (doi: 10.1186/1476-7120-6-22)
    1. Dandel M, Suramelasvili N, Lehmkuhl H, et al. 2D strain echocardiography a novel non-invasive tool for pretransplant evaluation of patients with dilated cardiomyopathy. J Heart Lung Transplant. 2007;26(2S):S239.
    1. Dandel M, Weng Y, Siniawski H, et al. Long-term results in patients with idiopathic dilated cardiomyopathy after weaning from left ventricular assist devices. Circulation. 2005;112(suppl):I-37–I-45.
    1. Jasaityte R, Dandel M, Lehmkuhl HB, Hetzer R. Echocardiographic prediction of short–term outcome in patients with idiopathic dilated cardiomyopathy referred for transplantation. Transplant Proc. 2008 (in press)

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