European Heart Journal Advance Access originally published online on December 21, 2006
European Heart Journal 2007 28(2):269-270; doi:10.1093/eurheartj/ehl431
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Myocardial deformation to determine transmurality of myocardial infarction?: Reply
Medical Clinic I
University Aachen Pauwelsstrasse
52074 Aachen
Germany
E-mail address: rhoffmann{at}ukaachen.de
Medical Clinic I
University Aachen
Germany
We read with interest the letter by Zhang et al.1 discussing their own as well as our article. In their own study, Zhang et al. used myocardial velocity and Doppler derived strain in patients with an acute myocardial infarction to define the transmurality of myocardial infarction.2 Doppler-derived strain and strain-rate analysis have been shown to be very angle dependent and limited by significant noise artefacts.3 These difficulties have limited the use of Doppler-derived strain in clinical practice, as stated in our article. This statement may be repeated at any time. A superiority of speckle tracking in terms of measurement accuracy has not been claimed by us. A superiority of speckle tracking in terms of measurement accuracy will be difficult to show as a high concordance between speckle-tracking-based strain and Doppler-based strain which has been reported.4 Still, in contrast to Doppler-derived strain, speckle tracking lacks the angle-dependency and easily provides data for whole predefined ventricular segments in contrast to the analysis for only one point in space provided by Doppler-based strain analysis. Thus, noise artefacts are reduced substantially. Looking into the reported accuracies from our study as well as the study by Zhang et al. to differentiate different myocardial viability conditions, one might conclude that the results are not far off. The distinction between transmurality vs. non-transmurality considering a cut-off of 50% in hyperenhancement by MRI used in our study, relates to the distinction between endocardial vs. non-transmural infarction by Zhang with a reported sensitivity of 81.3% and a specificity of 83.3%.2,5 The authors may still be commended for their high accuracy in the analysis of the different degrees of infarct transmurality in patients soon after acute myocardial infarction when MRI has limitations to define the final extent of infarcted tissue. On this background, the novel method of speckle-tracking-based analysis used in our study should be considered to have significant advantages in clinical practice. These advantages relate less to absolute measurement differences. However, we believe that the important practical advantages are likely to result in greater clinical acceptance of this myocardial deformation imaging technique for assessment of myocardial viability.
References
- Zhang Y and Sanderson JE. (Published online ahead of print) Myocardial deformation to determine transmurality of myocardial infarction. Eur Heart J.
- Zhang Y, Chan AK, Yu CM, Yip GW, Fung JW, Sam WW, So NM, Wang M, Wu EB, Wong JT, Sanderson JE. (2005) Strain rate imaging differentiates transmural from non-transmural infarction. A validation study using delayed-enhancement magnetic resonance imaging. J Am Coll Cardiol 46:864871.
[Abstract/Free Full Text] - Urheim S, Edvardsen T, Torp H, Angelsen B, Smiseth OA. (2000) Myocardial strain by Doppler echocardiography: validation of a new method to quantify regional myocardial function. Circulation 102:11581164.
- Modesto KM, Cauduro S, Dispenzieri A, Khandheria B, Belohlavek M, Lysyansky P, Friedman Z, Gertz M, Abraham TP. (2006) Two-dimensional acoustic pattern derived strain parameters closely correlate with one-dimensional tissue Doppler derived strain measurements. Eur J Echocardiogr 7:315321.
[Abstract/Free Full Text] - Becker M, Hoffmann R, Kuhl HP, Grawe H, Katoh M, Kramann R, Bücker A, Hanrath P, Heussen N. (2006) Analysis of myocardial deformation based on ultrasonic pixel tracking to determine transmurality in chronic myocardial infarction. Eur Heart J 27:25602566.
[Abstract/Free Full Text]
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