Left ventricular rotation and twist in patients with hypertrophic cardiomyopathy evaluated by two-dimensional ultrasound speckle-tracking imaging / 中国医学科学院学报

<p><b>OBJECTIVE</b>To assess the left ventricular rotation and twist in patients with hypertrophic cardiomyopathy (HCM) by 2-dimensional ultrasound speckle-tracking imaging (STI).</p><p><b>METHODS</b>Two-dimensional images of left ventricule (LV) at basal and apical short-axis views were acquired in 20 patients with HCM and 20 healthy subjects to evaluate LV rotation. LV twist were defined as rate of apical LV rotation to the basal. Peak rotation (Prot) and the time to Prot in basal and apical short axis views were measured separately. Peak twist (Ptw), twist at aortic valve closure (AVCtw), twist at mitral valve opening (MVOtw), untwisting rate (Untw R), and half time of untwisting (HTU) were calculated.</p><p><b>RESULTS</b>Compared with the control group, the value of Prot-MV, Prot-AP, Ptw, time to Ptw, AVCtw, MVOtw, and HTU significantly increased (all P < 0.05) and the Untw R significantly decreased (P < 0.05) in the HCM group. In the HCM group, time to Prot in apical view was significantly higher than that in basal view.</p><p><b>CONCLUSION</b>STI can noninvasively evaluate the characteristics of LV twist and rotation in patients with HCM.</p>

Assessment of left ventricular torsion in patients with anterior wall myocardial infarction before and after revascularization using speckle tracking imaging / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Rotation of the left ventricular (LV) apex to the base, or LV torsion, is related to myocardial contractility and structure and has recently been recognized as a sensitive indicator of cardiac performance, but it has been difficult to measure. The recent development of 2-dimensional (2D) speckle tracking imaging (STI) may provide a powerful means of assessing LV torsion. This study was conducted to evaluate the global and regional LV twist in patients with anterior wall myocardial infarction (AMI) disease before and after revascularization by STI.</p><p><b>METHODS</b>2D STI was performed in 35 AMI patients before and one month after revascularization, as well as in 32 normal controls. Left ventricular global and regional rotations were obtained at basal and apical short-axis levels; LV torsion was defined as apical rotation relative to the base. The time sequences were normalized to the percentage of systolic and diastolic duration.</p><p><b>RESULTS</b>Before revascularization, LV peak regional and global torsion in patients with AMI were significantly reduced as the result of reduced apical and basal rotation relative to those of normal control group (all P < 0.001); most significantly in the anterior and anterior-septal regions (P < 0.001); one month after revascularization, there were significant changes in peak rotation at either the base or apex relative to pre-revascularization values (all P < 0.001). Similarly, peak regional and global LV torsion were increased significantly (all P < 0.001). Global torsion inversely correlated with EDV (r = -0.605, P = 0.028) and ESV (r = -0.638, P = 0.019); and positively correlated with LVEF (r = 0.630, P = 0.021). Tight relations were also found between torsion and LV longitudinal and short axis function.</p><p><b>CONCLUSIONS</b>Systolic torsion was decreased in AMI patients. Revascularization therapy can improve the LV function of the AMI patients. STI has a potential to quantify left ventricular global and segment torsion in patients with AMI, and may make the assessment more available in clinical and research cardiology.</p>

Validation of real-time three-dimensional echocardiography for quantifying left and right ventricular volumes: an experimental study / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Assessment of the left ventricular (LV) and the right ventricular (RV) volumes and their functions is important for prognostic prediction and clinical decision making. We compared the accuracy for quantifying the LV and the RV volumes in vitro between conventional two-dimensional echocardiography (2DE) and real-time three-dimensional echocardiography (RT3DE).</p><p><b>METHODS</b>The volumes of 37 rubber-models (10 regularly shaped to simulate normal LV, 7 shaped to simulate LV with symmetric aneurysm, 8 shaped to simulate LV with asymmetric aneurysm, and 12 irregularly shaped to simulate normal RV) and 10 excised canine hearts were measured by RT3DE and 2DE. On RT3DE "full volume" imaging, the inner-surfaces of the rubber-models and canine LV and RV were outlined and the volumes were measured using 2-, 4-, 8- and 16-plane methods with the RT3DE analysis software. On 2DE imaging, the volumes were measured by the Simpson method. The LV and RV volumes measured by drained water were served as reference values, with which we compared RT3DE and 2DE data.</p><p><b>RESULTS</b>In rubber models mimicking normal LV and LV with symmetric aneurysms, RT3DE results were strongly correlated with reference values (r = 0.795 - 0.998) and there was a good correlation between 2DE estimates and reference values (r = 0.715 - 0.729). There were no significant differences between RT3DE estimates, 2DE results and reference values (P > 0.05). In rubber models mimicking the RV and LV with asymmetric aneurysm, RT3DE strongly correlated with reference values (r = 0.765 - 0.988), but 2DE weakly correlated with reference values (r = 0.518 - 0.592). There were no differences between RT3DE and reference values (P > 0.05), but a significant difference between 2DE and reference values occurred (P < 0.05). For excised canine hearts, there was a strong correlation between RT3DE and reference values (r = 0.728 - 0.914), while 2DE showed a less obvious correlation (r = 0.502 - 0.615). Again, there were no significant differences between RT3DE and reference values (P > 0.05), but there was a significant difference between 2DE and reference values (P < 0.05).</p><p><b>CONCLUSIONS</b>RT3DE can accurately quantify LV and RV volumes and provides a new tool to evaluate LV and RV function. For LV and RV measurements by RT3DE, 8-plane strategy is the optimum choice for accuracy and convenience.</p>

Real-time three-dimensional myocardial contrast echocardiography in assessment of myocardial perfusion defects / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Both real-time three-dimensional echocardiography (RT3DE) and myocardial contrast echocardiography (MCE) are novel imaging techniques. The purpose of this study was to confirm the feasibility and accuracy of RT3DE combined with MCE for quantitative evaluation of myocardial perfusion defects.</p><p><b>METHODS</b>Thirteen dogs underwent ligation of the left anterior descending artery (LAD, n = 6) or distal branch of the left circumflex artery (LCX, n = 7) under general anaesthesia. Three to four ml of a perfluoropropane (C3F8) microbubble contrast agent was injected intravenously to assess the resulting myocardial perfusion defects with a commercially available Philips SONOS-7500 ultrasound system. After removal of the dog hearts, Evans blue dye was injected via the left and right coronary arteries to stain the myocardium at risk. In vitro anatomic measurements of myocardial mass after removal of the animals' hearts were used as controls.</p><p><b>RESULTS</b>Left ventricular (LV) mass determined by RT3DE ranged 36.7 - 68.9 g [mean, (54.6 +/- 9.6) g] before coronary artery ligation, and correlated highly (r = 0.99) with in vitro measurement of LV mass [range, 38.9 - 71.1 g; mean, (55.6 +/- 9.3) g]. There was no significant difference between RT3DE and in vitro measurements of LV mass [range, 36.7 - 68.9 g; mean, (51.3 +/- 12.5) g. Or range, 38.9 - 71.1 g; mean, (53.7 +/- 12.3) g, respectively] and under-perfused mass [range, 0 - 21.4 g; mean, (12.0 +/- 6.9) g. Or range, 0 - 19.8 g; mean, (10.8 +/- 6.3) g, respectively] after the LAD ligation (P > 0.05). Likewise, no significant difference was present between RT3DE and in vitro measurements of LV mass [range, 50.1 - 65.4 g; mean, (57.5 +/- 5.9) g. Or range, 51.5 - 65.8 g; mean, (57.3 +/- 6.4) g, respectively] and under-perfused mass [range, 0 - 25.6 g; mean, (13.3 +/- 9.6) g. Or range, 0 - 22.7 g; mean, (12.8 +/- 8.1) g, respectively] after the LCX ligation (P > 0.05). For all the animals with coronary ligation, LV mass measured by RT3DE ranged 35.9 - 68.6 g [mean, (54.8 +/- 10.0) g] and there was no significant difference between RT3DE and in vitro measurements of LV mass and under-perfused mass (P > 0.05, r = 0.99). Further, the under-perfused mass derived from RT3DE [range, 0 - 25.6 g; mean, (12.7 +/- 8.2) g] correlated strongly with the in vitro measurements [range, 0 - 22.7 g; mean, (11.9 +/- 7.2) g] (r = 0.96).</p><p><b>CONCLUSION</b>RT3DE with MCE is a rapid and accurate method for estimating LV myocardial mass and quantifying perfusion defects.</p>

Real-time three-dimensional echocardiography for quantifying left ventricular mass / 中国医学科学杂志(英文版)

<p><b>OBJECTIVE</b>To test the accuracy of real-time three-dimensional echocardiography (RT3DE) imaging system for evaluating left ventricular mass (LVM) in phantom and excised canine heart.</p><p><b>METHODS</b>Ten left ventricular (LV) wall phantoms made of two rubber-bursas, ten excised canine hearts underwent RT3DE and two-dimensional echocardiography (2DE). In RT3DE "full volume" imaging, the myocardial volume was measured using 2, 4, 8, and 16-plane method with the analysis software of RT3DE. Mass was then calculated by multiplying the resulting myocardial volume by specific density of myocardial tissue. In 2DE the masses were measured by area-length method. The true LV wall phantom mass was measured by water displacement and the canine LVM was weighed by anatomy, which served as a reference standard. We compared RT3DE or 2DE with true mass.</p><p><b>RESULTS</b>In LV wall phantoms, RT3DE correlated with true masses strongly (r = 0.813-0.994) and weakly correlated between 2DE and true masses (r = 0.628). In excised canine hearts, there is an excellent correlation between RT3DE and true masses (r = 0.764-0.991), while 2DE value showed a lesser correlation (r = 0.514). There are no difference between RT-3DE and true masses (P > 0.05) but different between 2DE and true masses (P < 0.05). In different planes, there was no difference between 8-plane and 16-plane (P > 0.05) but different between 8-plane and 2, 4-plane (P < 0.05).</p><p><b>CONCLUSION</b>RT3DE can accurately quantify LVM and provide a new tool to evaluate LV function. For LVM by RT3DE, 8-plane measurement method is the best choice for accuracy and convenience.</p>