Resting Ultrasonic Tissue Characterization and Dobutamine Stress Echocardiography for Prediction of Functional Recovery in Chronic Left Ventricular Ischemic Dysfunction.

Abstract

revious studies have shown the usefulness of lowdose dobutamine stress echocardiography (DSE) for the assessment of viable myocardium and the prediction of functional recovery after revascularization in patients with chronic coronary disease. [1][2][3][4][5][6][7][8] However, there were wide ranges of sensitivity, specificity, and accuracy (74-91%, 73-95%, and 73-91%, respectively) for prediction of reversible dysfunction, possibly because most studies included patients with various degrees of regional and global left ventricular (LV) function. In addition, more precise equipment may be required in order to obtain a satisfactory level of the accuracy with DSE.Recently, a cardiac cycle-dependent variation of ultrasonic integrated backscatter (IBS-CV), which reflects intramural contractile performance and myocardial thickening, [9][10][11][12] has been anticipated as useful for assessing myocardial viability and predicting LV functional recovery in patients with reperfused acute myocardial infarction. 13 In the setting of acute myocardial infarction, the characteristic of salvageable myocardium was reversibility of the blunted amplitude of IBS-CV. Pasquet et al reported that resting IBS-CV closely paralleled contractile reserve in patients with chronic LV ischemic dysfunction, 14 but further study is required to elucidate several aspects of the usefulness of IBS. We have Japanese Circulation Journal Vol. 65, May 2001 gradually increased the number of opportunities for evaluating the pertinence of revascularization in patients with chronic LV ischemic dysfunction, and so we designed this study to determine the sensitivity, specificity, and accuracy of resting % systolic wall thickening (resting WT), resting IBS-CV, DSE, and low-dose dobutamine stress IBS-CV (DSE-IB) in predicting functional recovery in patients with chronic LV ischemic dysfunction, and we also evaluated the effect of global LV function on the accuracy of this study. Methods Study PopulationWe studied 48 patients with a previous (mean 9±5 months after the onset) myocardial infarction between June and December, 1998. For inclusion in the study, the following criteria needed to be fulfilled.1. Previous myocardial infarction including at least one akinetic segment as demonstrated by transthoracic echocardiography.2. A suitable acoustic window to allow DSE with IBS. 3. Clinical evidence of myocardial ischemia, and scheduling for percutaneous transluminal coronary angioplasty (PTCA).4. No cardiac event during the follow-up period after revascularization.All patients underwent combined low-and high-dose DSE with IBS and radionuclide ventriculography (RNV) before PTCA. For a mean of 10 months (range, 5-24 months) after PTCA, transthoracic echocardiography at rest and the IBS study were repeated. All patients gave This study was designed to assess the diagnostic accuracy of the percentage of resting systolic wall thickening (WT), dobutamine stress echocardiography (DSE), resting cyclic variation of integrated backscatter (IBS-CV), and low-dose dobutamine...

Prediction of Functional Recovery of the Left Ventricle After Coronary Revascularization in Patients With Prior Anterior Myocardial Infarction. A Myocardial Integrated Backscatter Study.

“…As mentioned before, the temporal relationship of CV with the cardiac cycle is also a useful marker of myocardial viability. 7 In the present study, the normalized time delay was, though used as a cutoff point for grouping, significantly longer in group B than in group A, which supports the data of Pasquet et al 8 and Homma et al 9 in patients with chronic ischemic LV dysfunction as well as those with an acute MI. 7 …”

“…Takiuchi et al used it to assess myocardial viability in patients with reperfused acute MI and found that the recovery of visually assessed regional contraction followed that of CV (for both magnitude of CV and normalized time delay). 7 For patients with chronic LV ischemic dysfunction, on the other hand, Pasquet et al 8 and later Homma et al 9 showed the usefulness of IBS for assessing contractile reserve in combination with dobutamine echocardiography. Naito et al demonstrated that in patients with a remote MI, the magnitude of CV correlated with the percent 201 Tl uptake on perfusion imaging.…”

“…Numerous studies have shown that the magnitude of CV reflects intrinsic myocardial contraction in patients with cardiomyopathy or ischemic heart disease, and it is generally accepted that the greater magnitude of CV, the more viable myocardium exists. 8,9 On the other hand, a decreased or delayed pattern of CV may indicate segmental viability of myocardium that has late systolic shortening and so does not always reflect irreversible ischemic injury. 6,8 Indeed, the LVEF significantly improved in group B as well as in group A, which is not surprising given that even a dyskinetic myocardial segment may have a nontransmural MI or even normal myocardium histologically 26,27 and in addition, patients with scar formation on 2-dimenstional echocardiography were excluded from the present study.…”

“…Recently, it was reported that the cyclic variation (CV) of integrated backscatter (IBS), which reflects intrinsic contractile performance, 1-6 can predict myocardial viability in patients with reperfused acute myocardial infarction (MI), 7 but this method has not been validated for chronic LV dysfunction. [8][9][10] The purpose of this study was, therefore, to determine whether IBS could identify hibernating myocardium and predict LV functional recovery after coronary revascularization in patients with a remote anterior MI. …”

Left Ventricular Diastolic Dysfunction Induced by Cyclophosphamide in Blood Stem Cell Transplantation.

“…24,25) Currently, sophisticated UCG techniques are used to improve the visualization of cardiac microstructure. [26][27][28] Ultrasonic tissue characterization such as integrated backscatter and tissue harmonic imaging may have enabled us to distinguish myocardial edema from hypertrophy in more detail.…”