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ABSTRACT: The recent development of 2-dimensional strain (2D strain) imaging can provide a powerful alternative for assessing left ventricular
(LV) torsion. This study was conducted to evaluate the global and regional left ventricular twist by 2D strain in patients
with anterior wall myocardial infarction (AMI). A total of 55 AMI patients were divided into two groups according to their
ejection fraction (EF) values (group A: LVEF ⩾ 50%; group B: LVEF < 50%), and 35 normal people served as the control group.
Using 2-dimensional strain software, global and regional LV rotation and displacement were obtained at two planes. Compared
with the control group, patients of group A showed reduced peak LV twist of the anterior and anterior-septal wall (9.26±1.89
vs 10.74±2.67; 9.71±1.71 vs 11.36±2.29, both P < 0.05), but the radial displacement and global twist were maintained (P > 0.05). Differently, regional and global LV twist and radial displacement in patients of group B deceased significantly,
especially in the anterior and anterior-septal wall, as compared with patients in the control or group A (both P < 0.05). Moreover, a strong correlation was noted between peak twist and radial displacement; the twist-displacement loop
was markedly distorted in patients of group B. This study demonstrated that 2D strain has a potential ability for quantification
of left ventricular global and segment twist and radial displacement in patients with coronary artery disease.
Frontiers of Medicine in China 04/2012; 4(1):71-76.
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ABSTRACT: To assess the normal value of left ventricular twist (LVtw) and examine the changes with normal aging by 2-dimensional ultrasound
speckle-tracking imaging (STI), 121 healthy volunteers were divided into three age groups: a youth group (19–45 y old), a
middle-age group (46–64 y old) and an old-age group (≥65 y old). Basal and apical short-axis images of left ventricular were
acquired to analyse LV rotation (LVrot) and LVrot velocity. LVtw and LVtw velocity was defined as apical LVrot and LVrot velocity
relative to the base. Peak twist (Ptw), twist at aortic valve closure (AVCtw), twist at mitral valve opening (MVOtw), untwisting
rate (UntwR), half time of untwisting (HTU), peak twist velocity (PTV), time to peak twist velocity (TPTV), peak untwisting
velocity (PUV), time to peak untwisting velocity (TPUV) were separately measured. The results showed that the normal LV performs
a wringing motion with a clockwise rotation at the base and a counterclock-wise rotation at the apex (as seen from the apex).
The LVtw velocity showed a systolic counterclock-wise twist followed by a diastolic clockwise twist. Peak twist develops near
the end of systole (96%±4.2% of systole). With aging, Ptw, AVCtw, MVOtw, HTU and PUV increased significantly (P<0.05) and UntwR decreased significantly (P<0.05). However, no significant differences in TPUV, PTV and TPTV were noted among the 3 groups (P>0.05). It is concluded that LV twist can be measured non-invasively by 2-dimensional ultrasound STI imaging. The age-related
changes of LVtw should be fully taken into consideration in the assessment of LV function.
Key wordsechocardiography-speckle tracking imaging-left ventricular-twist-rotation
Journal of Huazhong University of Science and Technology 04/2012; 27(6):691-695. · 0.38 Impact Factor
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ABSTRACT: 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.
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.
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.
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.
Chinese medical journal 08/2008; 121(16):1543-8. · 0.86 Impact Factor
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ABSTRACT: To assess the left ventricular rotation and twist in patients with hypertrophic cardiomyopathy (HCM) by 2-dimensional ultrasound speckle-tracking imaging (STI).
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.
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.
STI can noninvasively evaluate the characteristics of LV twist and rotation in patients with HCM.
Zhongguo yi xue ke xue yuan xue bao. Acta Academiae Medicinae Sinicae 03/2008; 30(1):58-62.
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ABSTRACT: The left ventricular twist was evaluated by 2-dimensional ultrasound speckle-tracking imaging (STI) in 50 patients with hypertension with normal geometric left ventricle (LV) and 45 normal subjects as control group. The mean value of LV rotation was obtained at each plane using STI. LV twist and twist velocity were defined as apical rotation/rotation rate relative to the base respectively. To adjust the intersubject differences in heart rates, the time sequence were normalized. The results showed that peak twist developed near the end of systole. Peak LV twist was significantly higher in patients with hypertension than normal controls (P<0.001). The diastolic untwisting mainly occurred in early diastole ( approximately 38%). Compared with normal controls, untwisting rate (Untw R) in patients with hypertension was significantly reduced (P<0.001), and untwisting half-time (UHT) was significantly delayed (P<0.05). This study demonstrated that STI has a potential ability to evaluate the early change of heart function in patients with hypertension by measuring the twist of LV.
Journal of Huazhong University of Science and Technology 02/2008; 28(1):114-7. · 0.38 Impact Factor