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 (> or = 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.
Aging ; Echocardiography ; Heart Ventricles/anatomy & histology ; Heart Ventricles/*ultrasonography ; Ventricular Function, Left/*physiology ; Young Adult

OBJECTIVETo test the accuracy of real-time three-dimensional echocardiography (RT3DE) imaging system for evaluating left ventricular mass (LVM) in phantom and excised canine heart.

METHODSTen 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.

RESULTSIn 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).

CONCLUSIONRT3DE 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.

Animals ; Dogs ; Echocardiography, Three-Dimensional ; instrumentation ; Heart Ventricles ; anatomy & histology ; diagnostic imaging ; Phantoms, Imaging

OBJECTIVETo explore the methods for constructing the digital three-dimensional model of fetal heart.

METHODSOriginal two-dimensional CT image data sets were collected from 4 abortion fetuses with fetal malformations but not heart malformation or chromosomal abnormalities. The three-dimensional fetal heart model was reconstructed using Mimics14.0 software.

RESULTSIn the reconstructed three-dimensional fetal heart, the left atrium, left ventricle, right atrium, right ventricle, the ascending aorta, the main pulmonary and their branches, the superior cava and inferior vena cava were marked with different colors, and these structures could be displayed individually or with other structures. This model also allowed three-dimensional arbitrary scaling, shifting or rotation at any angle, and the diameter of the each vessel could be measured with the software.

CONCLUSIONThe fetal heart model can be successfully reconstructed from the CT datasets using three-dimensional reconstruction software to facilitate clinical and anatomical teaching.

Female ; Fetal Heart ; anatomy & histology ; Heart Atria ; anatomy & histology ; Heart Defects, Congenital ; Heart Ventricles ; anatomy & histology ; Humans ; Imaging, Three-Dimensional ; Models, Anatomic ; Pregnancy ; Software ; Tomography, X-Ray Computed ; Vena Cava, Inferior ; anatomy & histology

A 3D model of heart configurations and interior structures has been constructed using Visual C++ visualization toolkit based on the Dataset of Visible Chinese Human. The finite element model of left ventricular is obtained from the heart structure model. Both ventricular wall and blood in the cavity are modeled by finite element mesh. The fluid-structure coupling of the left ventricle and blood has been constructed using an arbitrary Lagrange-Euler algorithm. Based on these models, the fluid-structure interaction of the left ventricle and blood in the filling phase is simulated. The simulation result successfully reproduced the biphasic filling flow consisting of early rapid filling and atrial contraction, which is similar to the clinical observation. This study provides a feasible method with which we can use image-based fluid-structure simulation to analyse the structure and haemodynamics properties of heart. It could be applied in heart functional investigations and clinical applications.
Algorithms ; Computer Simulation ; Finite Element Analysis ; Heart ; physiology ; Heart Ventricles ; anatomy & histology ; Hemodynamics ; Humans ; Imaging, Three-Dimensional ; Models, Cardiovascular

This study evaluated pulsed TDI variables including the isovolumic time interval and duration of the major wave in a population of large healthy dogs. Longitudinal myocardial motion at the septal mitral annulus was evaluated with pulsed TDI in 45 healthy adult dogs. Maximal myocardial velocities, isovolumic time intervals, and duration of the myocardial waves were measured. The correlation between time intervals and velocity variables was also investigated. The mean maximal systolic velocity was 6.92 +/- 1.78 cm/sec, the mean early diastolic velocity (Em) was 6.58 +/- 1.81 cm/sec, the mean late diastolic velocity (Am) was 5.10 +/- 2.00 cm/sec, the mean isovolumic contraction time (IVCT) was 53.61 +/- 95.13 msec, and the mean isovolumic relaxation time (IVRT) was 26.74 +/- 57.24 msec. The early diastolic mitral inflow velocity (E)/Em ratio was 10.94 +/- 3.27 while the Em/Am ratio was 1.40 +/- 0.40. There was a negative correlation between Am duration and Am amplitude, and a positive correlation between the IVRT and Em/Am ratio (p < 0.05). The normal LV parameter using pulsed TDI method could be used as the reference range for identifying myocardial dysfunction in dogs.
Animals ; Dogs/*anatomy & histology ; Female ; Heart Ventricles/*ultrasonography ; Male ; Mitral Valve/*ultrasonography ; Ultrasonography, Doppler, Pulsed/methods/*veterinary

Autonomic nervous system plays an important role in the regulation of mammalian heart, and it is divided into the sympathetic and parasympathetic (vagal) subsystems. The parasympathetic (vagal) control of the atria involves modulation of chronotropic, dromotropic and inotropic activities, but the role of the parasympathetic innervation of the ventricles is still unclear. There is a common misconception that the sympathetic nerves innervate all over the heart; while the parasympathetic nerves only innervate the superventricular part of the heart, but not the ventricles. Recent evidence indicates that the cholinergic innervation of the left ventricle is functionally very important in some mammalian species. The present article reviews the evidence of vagal control in the ventricles from the anatomy and histochemistry, molecular biology, and function areas. Additionally we overview the vagal (muscarinic) regulation of cardiac contractile function and its signal transduction.
Animals ; Heart Ventricles ; anatomy & histology ; innervation ; metabolism ; Humans ; Myocardial Contraction ; physiology ; Receptors, Muscarinic ; metabolism ; Signal Transduction ; physiology ; Vagus Nerve ; physiology

The main purpose of this study is to observe and analyze the characteristics and the clinical significance of long-term echocardiogram data in patients after mechanical aortic valve replacement operation. Fifty-five cases were recruited over 5 years after mechanical aortic valve replacement operation, with complete echocardiogram examination profiles. The 55 subjects were divided into predominate aortic stenosis group and predominate aortic regurgitation group, based on preoperative examinations. And another way of division was also carried out that according to the effective orifice area index (EOAI), the subjects were divided into three groups, i. e. , severe prosthesis-patient mismatch (PPM) group, moderate PPM group, and non PPM group. Characteristics of long-term echocardiogram data of the subjects were analyzed. Patients with aortic stenosis showed significantly decreased thickness of intraventricular septum and left ventricular posterior wall about half a year after operation (P < 0.05). Half a year after operation, patients with aortic regurgitation showed decreased left ventricular internal dimension diastole and left ventricular internal dimension systole, and increased ejection fraction (P < 0.05). Differences in mean aortic valve pressure gradient, forward blood flow across the aortic valves, and ejection fraction were not significant among those with severe PPM, moderate PPM, and non PPM groups (P > 0.05). Number of cases of ascending aorta dimension increased as time goes on and pathogenesis of other valve diseases. A conclusion could be drawn that the heart function of patients with aortic valve disease could be improved after mechanical aortic valve replacement operation, but pathologies in other valves and ascending aorta might be increased, and therefore periodical postoperative echocardiogram evaluation with long-term pharmaceutical therapy could be necessary.
Aortic Valve Stenosis ; surgery ; Echocardiography ; Heart Valve Prosthesis ; Heart Valve Prosthesis Implantation ; Heart Ventricles ; anatomy & histology ; Humans ; Postoperative Period ; Systole ; Treatment Outcome

Wistar rats of 8, 10 and 12-week-old were chosen for study of the relationship between cardiac growth and its gene expression profile changes during maturation. The ultrasonic parameters of rat hearts were recorded before sacrifice, then total RNA of left ventricle were extracted and gene expression profiles were analyzed by cDNA microarray. During growth from 8 weeks to 12 weeks, the body weight increased by 45.5% (287+/-13 g vs 197+/-10 g), and the increment in the first two-week period was equal to that of the second two-week period. The mass of left ventricle and the posterior wall thickness increased by 27.7% (0.60+/-0.03 g vs 0.47+/-0.02 g) and 23.6% (2.04+/-0.04 mm vs 1.65+/-0.13 mm), respectively, and their increment in the first two-week period was much more than that in the second one. Meanwhile, the gene expression profile of the left ventricle changed significantly, which involved cellular structure, metabolism, oxidative stress, signal transduction, etc. Compared with the 8-week-old rats, these genes were mostly up-regulated in 10-week-old rats, while for 12-week-old rats, the gene expression profile of the left ventricle recovered to the pattern of 8-week-old rats again on the whole. These results suggest that the relationship between the changes in cardiac function and gene expression profile can be analyzed comprehensively with the technique of microarray, and that the changes in gene expression profile of the left ventricle during rat maturation adapt to the physiological growth of heart, which is of benefit for keeping the metabolism balance between materials and energy.
Animals ; Heart ; growth & development ; physiology ; Heart Ventricles ; anatomy & histology ; Male ; Myocardium ; cytology ; metabolism ; Oligonucleotide Array Sequence Analysis ; Rats ; Rats, Wistar ; Transcriptome

OBJECTIVETo study the three-dimensional structure of ventricular myocardial fiber in human heart.

METHODSEight human heart were obtained from male donors aged 81.9-/+7.2 years with a heart weight of 455.6-/+65.7 g. Each sample was immersed in water and scanned by diffusion tensor magnetic resonance imaging (DT-MRI) using a 3 Tesla Exicte HD by an eight-channel head coils. The duration was 18.6-/+5.2 h from heart arresting to the scanning. The data were obtained using the protocol of single shot echo planar imaging (sshEPI) and sensitivity encoding (SENSE). The SENSE-sshEPI-scans (TE/TRZ86.4/2000 ms) of the whole heart were carried out (b=1000 s/mm(2), voxels 128x128, resolution 1.1 mmx1.1 mmx(3) mm, and FOV 14 cmx14 cm). Fiber tracking and reconstruction were performed using GE Advantage Windows Workstation. The three-dimensional structure of the ventricular myocardial fiber was observed.

RESULTSThe left ventricular myocardial fibers showed two layers with different directions of alignment in such regions as the anterior, septum, and posterior walls and the free left ventricular wall. The subendocardial layer ran obliquely from the base to the apex, and the middle layer ran obliquely upward from the base to the apex. The two layers were linked together and aligned in the pattern of helical coils near the apex.

CONCLUSIONSThe three-dimensional structure of the myocardial fibers in human heart conforms to Torrent's hypothesis of helical ventricular myocardial band (HVMB).

Aged ; Aged, 80 and over ; Heart ; anatomy & histology ; Heart Ventricles ; anatomy & histology ; Humans ; Imaging, Three-Dimensional ; methods ; Magnetic Resonance Imaging ; Male ; Models, Anatomic ; Models, Cardiovascular ; Myocardial Contraction ; physiology ; Myocardium ; cytology ; Myocytes, Cardiac ; cytology

BACKGROUNDLeft ventricular hypertrophy (LVH) and geometric abnormality are associated with morbidity and mortality of cardiovascular disease and stroke. Hypertension is the major cause of LVH. Yet the prevalence and other risk factors of LVH and geometric abnormality in Chinese hypertensive population are unknown. The objective of this study was to investigate the prevalence and risk factors of LVH and geometric abnormality in community-based Chinese hypertensive population.

METHODSThe study was a community-based cross-sectional study, and comprised 4270 hypertension patients with integrated clinical and echocardiographic data. Left ventricular mass was measured by transthoracic echocardiography. LVH was diagnosed by using the criteria of over 49.2 g/m(2.7) for men and 46.7 g/m(2.7) for women. LV geometric patterns (normal, concentric remodeling, concentric or eccentric hypertrophy) were calculated according to LVH and relative wall thickness. Logistic regression model was used to determine the odds ratio (OR) and 95% confidence intervals (CI) of the risk factors of LVH.

RESULTSThe prevalence of LVH was 42.7% in 4270 hypertensive patients, with 37.4% in males and 45.4% in females, respectively. The prevalence of concentric remodeling, concentric or eccentric hypertrophy was 24.7%, 20.2%, and 22.6%, respectively. In Logistic regression model, female (OR 1.3, 95%CI 1.1 - 1.5, P < 0.01), age (OR 1.02, 95%CI 1.01 - 1.03, P < 0.01), body mass index (OR 1.2, 95%CI 1.15 - 1.20, P < 0.01), systolic blood pressure (OR 1.02, 95%CI 1.01 - 1.03, P < 0.01), and serum triglyceride (OR 1.10, 95% CI 1.00 - 1.20, P < 0.01) were risk factors of LVH. Female, age, body mass index, systolic blood pressure and serum triglyceride were also risk factors of left ventricular geometric abnormality.

CONCLUSIONSThe echocardiographic LVH is the major complication of patients with hypertension in rural area of China, especially for women. To effectively treat hypertension, weight loss and control of serum triglyceride may help to prevent LVH in hypertensive population.

Adult ; Aged ; Cross-Sectional Studies ; Echocardiography ; Female ; Heart Ventricles ; anatomy & histology ; pathology ; physiopathology ; Humans ; Hypertension ; epidemiology ; physiopathology ; Hypertrophy, Left Ventricular ; epidemiology ; Male ; Middle Aged ; Prevalence ; Risk Factors