Diastole ; physiology ; Exercise ; physiology ; Fractional Flow Reserve, Myocardial ; Heart Rate ; Humans ; Systole ; physiology ; Young Adult

To study the blood flow parameters for 2 anatomical segments of posterior cerebral artery (PCA) in normal singleton fetal.
 Methods: The blood flow velocity parameters peak systolic velocity (PSV), end diastolic velocity (EDV), time-average maximum velocity (TAMAXV), velocity time integral (VTI) and resistance parameters systolic peak velocity and end diastolic velocity ratio (S/D), pulsatility index (PI), resistance index (RI) for 2 anatomical segments in PCA were recorded. The first segment of the PCA (PCAS1) was recorded between the origin of PCA and the proximal part of the posterior communicating artery. The second segment of the PCA (PCAS2) was recorded at the distal part of the posterior communicating artery. The blood parameters in both PCAS1 and PCAS2 were analyzed by using Pearson correlation and multiple curves fitting with gestational age (GA). Paired student's t test was performed to compare the difference in blood parameter between PCAS1 and PCAS2.
 Results: The blood flow velocity parameters in both PCAS1 and PCAS2 were increased with the GA (P<0.0001), with the best fitted curves of Quadratic curve (P<0.0001). There were no correlations between resistance parameters in PCA and GA (P>0.05). Resistance parameters in PCAS1 were higher than those in PCAS2 (P<0.05).
 Conclusion: The blood flow velocity parameters in both PCAS1 and PCAS2 are increased with GA. The resistance parameters in both PCAS1 and PCAS2 do not change with GA. Study on the velocities and resistance in these 3 arterial branches provides a more comprehensive evaluation on the process of brain circulation.
Blood Flow Velocity ; physiology ; Diastole ; physiology ; Female ; Gestational Age ; Hemodynamics ; physiology ; Humans ; Posterior Cerebral Artery ; physiology ; Pregnancy ; Systole ; physiology

PURPOSE: To give a help in the interpretation of cardiac cine-MR examination, the extent, shape, and timing of appearance of signal void regions near atrioventricular(A-V) valve prospectively evaluated in the healthy population. MATERIALS AND METHODS: Using an axial gradient-echo technique with small flip angle, repetition time(TR) of 36 msec and echo time(TE) of 22 msec, 20 volunteers without known valvular abnormalities undertook cardiac cine-MR imaging including atrioventricualr valve areas. RESULTS: Transient signal void was observed within the atrium near the tricuspid(13/20 = 65%) and mitral valves(9/20 = 45%), respectively, which is so called "physiologic atrioventricular valvular insufficiency". Eight subjects revealed the signal void areas near both tricuspid and mitral valves but, 5 subjects didnot show any evidences of physiologic insufficiency. This physiologic condition does not extend more than lcm proximal to A-V valve plane and is generally observed only during early systole. Its morphology is semilunar or triangular configuration with the base to the valve plane in most cases of normal tricuspid insufficiency and small globular appearance in most cases of normal mitral insufficiency. CONCLUSION: Awareness of normal signal void areas near the A-V valve and their characteristics is critical in the interpretation of cardiac cine MR examinations and maybe helpfal in the study of the normal cardiac physiology.
Magnetic Resonance Imaging* ; Mitral Valve ; Mitral Valve Insufficiency ; Physiology ; Prospective Studies ; Systole ; Volunteers

This study was conducted to explore the geometrical changes of the mitral annulus during systole. The 3D shape of the mitral annulus was reconstructed in 13 normal subjects who had normal structure of the mitral apparatus using real-time 3D echocardiography (RT3DE) and 3D computer software. The two orthogonal (antero-posterior and commissure-commissure) dimensions, the areas (2D projected and 3D surface) and the non-planarity of the mitral annulus were estimated during early, mid and late systole. We demonstrated that the MA had a "saddle shape" appearance and it consistently enlarged mainly in the antero-posterior direction from early to late systole with lessening of its non-planarity, as was determined by 3D reconstruction using RT3DE and 3D computer software.
*Echocardiography, Three-Dimensional ; Humans ; Image Processing, Computer-Assisted ; Mitral Valve/cytology/*ultrasonography ; Software ; Systole/*physiology

The optimal plane for measurement of the right ventricular (RV) volumes by real-time three-dimensional echocardiography (RT3DE) was determined and the feasibility and accuracy of RT3DE in studying RV systolic function was assessed. RV "Full volume" images were acquired by RT3DE in 22 healthy subjects. RV end-diastolic volumes (RVEDV) and end-systolic volumes (RVESV) were outlined using apical biplane, 4-plane, 8-plane, 16-plane offline separately. RVSV and RVEF were calculated. Meanwhile tricuspid annual systolic excursion (TASE) was measured by M-mode echo. LVSV was outlined by 2-D echo according to the biplane Simpson's rule. The results showed: (1) There was a good correlation between RVSV measured from series planes and LVSV from 2-D echo (r = 0.73; r = 0.69; r = 0.63; r = 0.66, P < O. 25-0. 0025); (2) There were significant differences between RVEDV in biplane and those in 4-, 8-, 16-plane (P < 0.001). There was also difference between RV volume in 4-plane and that in 8-plane (P < 0.05), but there was no significant difference between RV volume in 8-plane and that in 16-plane (P > 0.05); (3) Inter-observers and intro-observers variability analysis showed that there were close agreements and relations for RV volumes (r = 0.986, P < 0.001; r = 0.93, P < 0.001); (4) There was a significantly positive correlation of TASE to RVSV and RVEF from RT3DE (r = 0.83; r = 0.90). So RV volume measures with RT3DE are rapid, accurate and reproducible. In view of RV's complex shape, apical 8-plane method is better in clinical use. It may allow early detection of RV systolic function.
Cardiac Volume ; Echocardiography, Three-Dimensional ; Electrocardiography ; Systole ; Ventricular Function, Right/*physiology

OBJECTIVETo investigate the therapeutic effectiveness of intracoronary implantation of autologous bone marrow mononuclear cells (BM-MNC) in miniswine model of reperfused myocardial infarction.

METHODSSixteen miniswine myocardial ischemic reperfusion injury models made by ligation of the distal one third segment of left anterior descending artery for 90 minutes were randomized into 2 groups. In BM-MNC group (n = 9), (3.54 +/- 0.90) X 10(8) BM-MNC were intracoronary injected, and in the control group (n = 7), phosphate buffered saline was injected by the same way. Echocardiographic and hemodynamic results, vessel density, and myocardial infarction size were evaluated and compared before and 4 weeks after cell transplantation.

RESULTSIn BM-MNC group, there were no differences between before and 4 weeks after transplantation in aspects of left ventricular ejection fraction (LVEF), interventricular septal thickness, left ventricular lateral and anterior septal wall thickness, cardiac output, or +dp/dtmax. In control group, LVEF, interventricular septal thickness, left ventricular lateral and anterior septal wall thickness, cardiac output, and +dp/dtmax decreased significantly 4 weeks after transplantation (P < 0.05). Left ventricular end-diastolic pressure and -dp/dtmax, did not change significantly before and after cell transplantation in both groups. Capillary density in BM-MNC group was greater than that in control group [(13.39 +/- 6.96)/high power field vs. (3.50 +/- 1.90)/high power field, P < 0.05]. Infarction area assessed by tetrazolium red staining and the infarction percentage decreased in BM-MNC group compared with those in control group (P < 0.05).

CONCLUSIONSTransplantation of BM-MNC into myocardium with ischemic reperfusion injury increases capillary density and decreases infarction area. It has significantly beneficial effect on cardiac systolic function rather than on diastolic function.

Animals ; Bone Marrow Cells ; cytology ; physiology ; Bone Marrow Transplantation ; Capillaries ; physiology ; Echocardiography ; Heart ; anatomy & histology ; physiology ; physiopathology ; Hemodynamics ; Myocardial Ischemia ; Random Allocation ; Swine ; Systole ; physiology ; Transplantation, Autologous ; physiology

According to the pulse-wave theory, the authors developed a new non-invasive instrument for measuring arterial elastic function. It collects the pulse waveforms from the arteries of four limbs as well as from the radial arteries of carpus. After signal pre-processing, it calculates the arterial elastic parameters by the pre-prepared algorithm and program. Individual parameters such as pulse wave velocity (PWV), ankle-brachial index (ABI), systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate (HR)can be obtained. At the same time, a series of clinical trials were conducted with reference to PWV and ABI, which confirmed the validity, accuracy and reliability of the instrument. The instrument can be used to determine the differences between cardiovascular patients and normal persons, as well as the extent of atherosclerosis. At the same time it can reflect the situation of vascular obstruction and screen the peripheral arterial disease. Therefore, it is of some value to the epidemiological study, prevention and early detection of cardiovascular disease.
Aging ; physiology ; Ankle ; blood supply ; Arteries ; physiopathology ; Arteriosclerosis ; physiopathology ; Blood Pressure ; physiology ; Brachial Artery ; physiopathology ; Elasticity ; physiology ; Humans ; Hypertension ; physiopathology ; Pulsatile Flow ; physiology ; Pulse ; Systole

This study of methodology was aimed to assess the feasibility of measuring different phase of left ventricular systole period with ultrasonic Doppler and synchronism electrocardiogram. We measured the phases of left ventricular systole period and left ventricular volumes in 13 normal persons, using spectrum of aortic valve orifice flow and synchronism electrocardiogram. The values measured by routine method and by Doppler method were compared. The correlation and agreement between the measures ascertained by the two ways were analyzed. The time parameters of end systole of left ventricule showed no significant difference between the two ways (P>0.05); there was high linear correlation between the two parameters (r=0.91, P<0.01); there were good agreements between the two parameters of the two ways by Bland-Altman analysis. The volume parameters of left ventricular systole end showed no significant difference between the two ways (P>0.05); there was high linear correlation between the two parameters (r=0.97, P<0.01); there were good agreements between the two volume parameters of the two ways. The volume in the left ventricular systole end determined by Doppler method and the volume in the left ventricular diastole end determined by the routine method showed no significant difference (P>0.05); there was high linear correlation between the two parameters (r=0.98, P<0.01); there was good agreement between the two volume parameters of the two ways. It is feasible to measure different phases of left ventricular systole period with the combined use of ultrasonic Doppler and synchronism electrocardiogram, and this combinaterial method and the routine method can be replaced with each other according to the clinical setting.
Adult ; Echocardiography, Doppler, Color ; methods ; Electrocardiography ; methods ; Feasibility Studies ; Female ; Heart Rate ; physiology ; Humans ; Male ; Middle Aged ; Systole ; physiology ; Ventricular Function, Left ; physiology

We analyzed Doppler echocardiographic data in 120 subjects with normal sinus rhythm; normals (NL, n=60, ages 54.1 15.1) and essential hypertensive patients (HT, n=60, ages 57.3 10.2). The IMP was calculated as follows: IMP=(ICT+IRT)/ET, ICT; isovolumic contraction time, IRT; isovolumic relaxation time, ET; ejection time. There were no significant differences in ejection fraction (EF), stroke volume index (SVI), cardiac index (CI), ET and ICT between NL and HT. There were, however, significant differences in deceleration time (DT), E/A ratio, IRT and the IMP between the two groups (199.5 45.6 msec vs 222.3 54.3 msec, p<0.01; 1.4 0.7 vs 0.9 0.2, p<0.01; 113.6 30.2 msec vs 134.2 29.6 msec, p<0.01; 0.6 0.1 vs 0.8 0.3, p<0.05). In HT, there were no differences in EF, SVI, CI, E/A ratio and DT between the NYHA I (Gp I, n=36) and II (Gp II, n=24) groups. However, ET of Gp II was significantly shorter than that of Gp I (259.4 43.5 msec vs 297.8 33.6 msec, p<0.01). ICT, IRT and the IMP were significantly increased in Gp II, compared to those of Gp I (64.4 23.9 msec vs 89.4 46.2 msec, p<0.05; 120.3 21.0 msec vs 155.2 28.5 msec, p<0.001; 0.6 0.2 vs 1.0 0.4, p<0.001). There were no differences in heart rate and mean blood pressure between Gp I and Gp II (70.9 11.4/min vs 66.3 11.4/min, p>0.05; 138.4 21.2 mmHg vs 131.3 19.9 mmHg, p>0.05). These data suggest that the IMP may be a useful parameter and an early indicator of left ventricular dysfunction in essential hypertensive patients with normal systolic function.
Adult ; Aged ; Diastole/physiology ; Echocardiography, Doppler* ; Female ; Human ; Hypertension/ultrasonography* ; Hypertension/physiopathology* ; Male ; Middle Age ; Systole/physiology ; Ventricular Function, Left/physiology*

The present study was designed to investigate the effects of high-saturated and high-unsaturated fatty acid diets on relaxation and contraction of the renal arteries in insulin resistance (IR) rats. Wistar rats were fed normal chow diet (control), high-saturated fatty acid diet or high-unsaturated fatty acid diet for 6 months (n=14 in each group). IR was evaluated by glucose infusion rate (GIR) of hyperinsulinemic euglycemic clamp. Blood pressure was measured via the tail-cuff method. Body weight (BW), plasma total triglyceride (TG), free fatty acid (FFA), insulin, fasting blood glucose (FBG) and nitric oxide metabolite (NO2(-)/NO3(-)) were compared among the three groups. The rats were sacrificed and the renal arterial rings were placed in the physiological tissue baths for measurement of vascular response to various agents. After the arterial rings were constricted with 3 mmol/L noradrenaline (NA), endothelium-dependent vasorelaxation to acetylcholine (ACh) and endothelium-independent vasorelaxation to sodium nitroprusside (NTP) were measured. Endothelium-dependent vasorelaxation to ACh was also observed in renal arterial rings incubated with L-arginine (L-Arg), N(omega)-nitro-L-arginine (L-NNA) and methylene blue (MB), respectively. Arterial contractility was evaluated from concentration-response curves to 10 nmol/L-100 micromol/L NA. Saturated or unsaturated fatty acids led to moderate rises in blood pressure (P<0.05). It was associated with higher levels of plasma lipids and lower whole body insulin sensitivity (P<0.01). There were no significant differences in BW, FBG, TG, insulin and FFA between saturated and unsaturated fatty acid-fed rats. A decrease in endothelium-dependent vasorelaxation of the renal arteries in saturated and unsaturated fatty acid-fed rats was observed (P<0.01), but there was no marked difference between the two high-fatty acid diet groups. Endothelium-dependent vasorelaxation was increased when the arteries were incubated with L-Arg and decreased when incubated with L-NNA and MB in both high-fatty acid diet groups (P<0.05, P<0.01). But no difference was found before and after incubation with L-Arg, L-NNA and MB in the control rats. In the mean time, endothelium-independent maximal vasorelaxation response of renal arteries to NTP and renal arterial contractile responses to cumulative dose of NA were assayed, and there was no difference among the three groups (P>0.05). Endothelium-dependent vasorelaxation was negatively correlated with systolic blood pressure and TG, and positively correlated with NO2(-)/NO3(-) and GIR. There was a significantly negative correlation between FFA and NO2(-)/NO3(-). The present study suggests that both high-saturated and unsaturated fatty acid diets result in hypertension associated with significantly decreased endothelium-dependent vasorelaxation, dyslipidemia and IR, and that decreased endothelium-dependent vasorelaxation induced by high fatty acid diets is associated with impaired L-Arg-NO-cGMP pathways.
Animals ; Dietary Fats, Unsaturated ; administration & dosage ; Endothelium, Vascular ; physiology ; Fatty Acids ; administration & dosage ; Insulin Resistance ; Male ; Nitric Oxide ; physiology ; Rats ; Rats, Wistar ; Renal Artery ; physiology ; Systole ; Vasoconstriction ; Vasodilation