Objective: To investigate the diagnosis value of myocardial work (MW) in evaluating left ventricular global systolic function among acute myocardial infarction (AMI) patients with preserved ejection fraction (LVEF). Methods: This study was a diagnostic trial in a prospective case-control design. AMI patients with preserved LVEF were enrolled as AMI(LVEF>50%) group and age and sex-matched healthy individuals undergoing healthy checkup in our hospital were collected as control group. Two-dimensional dynamic images, including standard apical two-chamber, long-axis and four-chamber views in 3 consecutive cardiac cycles were acquired. General clinical data, routine echocardiography and myocardial work parameters were obtained from all subjects. The indices were compared between the two groups. Intra-observer and inter-observer repeatability of myocardial work parameters were evaluated by intra-group correlation coefficient (ICC). Receiver operator characteristic (ROC) curve was used to determine the diagnostic value of global constructive work (GCW), global wasted work (GWW), global work efficiency (GWE) and global work index (GWI) on the reduction of left ventricular global systolic function in AMI(LVEF>50%) group. Results: There were 30 patients in AMI(LVEF>50%) group, the age was (67.3±9.7)years, and 14 cases were female(46.7%). Thirty participants were included in the control group, the age was (68.1±8.6)years, and 12 cases were female (40.0%). Compared with the control group, left ventricular end-diastolic diameter (LVEDD), left ventricular end-systolic diameter (LVESD), interventricular septum thickness (IVSD), left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), peak early diastolic velocity of mitral orifice/tissue Doppler velocity of posterior mitral annulus (E/e), left ventricular mass (LVM), left ventricular mass index (LVMI) were significantly higher, while E and e values were significantly lower in AMI (LVEF>50%) group (all P<0.05). Compared with the control group, GCW ((1 145.9±440.1)mmHg% (1 mmHg=0.133 kPa) vs. (1 425.7±355.4)mmHg%), GWE ((80.9±9.5)% vs. (87.3±5.5)%), GWI ((1 001.3±416.2)mmHg% vs. (1 247.6±341.7)mmHg%) and the absolute value of long axis integral strain (GLS) ((8.5±3.4)% vs. (11.4±3.7)%) were significantly lower, while peak strain dispersion(PSD)((101.3±66.4)ms vs. (74.7±31.9)ms) was significantly higher in AMI(LVEF>50%) group (P all<0 05). There was no significant difference in GWW((177.2±71.1)mmHg% vs. (155.7±64.6)mmHg%) between the two groups (P>0.05). The reproducibility of GCW, GWW, GWE and GWI within and between observers were satisfactory (all ICC>0.75). ROC curve analysis showed that all four parameters, GCW, GWW, GWE, and GWI, could be used for the diagnosis of reduced left ventricular systolic function in patients with AMI (LVEF>50%), and their areas under the ROC curve were 0.896,0.929,0.808,0.862. Conclusion: Myocardial work assessment is valuable on diagnosing left ventricular global systolic function reduction in AMI patients with preserved LVEF.
Female ; Humans ; Myocardial Infarction/diagnostic imaging* ; Reproducibility of Results ; Stroke Volume ; Systole ; Ventricular Function, Left

Right ventricular (RV) failure has become a deadly complication of left ventricular assist device (LVAD) implantation, for which desynchrony in bi-ventricular pulse resulting from a LVAD is among the important factor. This paper investigated how different control modes affect the synchronization of pulse between LV (left ventricular) and RV by numerical method. The numerical results showed that the systolic duration between LV and RV did not significantly differ at baseline (LVAD off and cannula clamped) (48.52%
Heart Failure/therapy* ; Heart-Assist Devices ; Humans ; Systole ; Ventricular Dysfunction, Right ; Ventricular Function, Right

systole and diastole, and vessel compression index) on CCTA associated with CT-FFR ≤ 0.80 were analyzed. Receiver operating characteristic analysis was performed to describe the diagnostic performance of CT-FFR ≤ 0.80 in detecting interarterial R-ACAOS.RESULTS: Significant differences were found in proximal vessel morphology, take-off level, intramural course, % proximal narrowing area, and MLA at diastole (all p < 0.05) between the normal and abnormal CT-FFR groups. Take-off level, intramural course, and slit-like ostium (all p < 0.05) predicted hemodynamic abnormality (CT-FFR ≤ 0.80) with accuracies of 0.69, 0.71, and 0.81, respectively. Patients with CT-FFR ≤ 0.80 had a higher prevalence of typical angina (29.4% vs. 7.8%, p = 0.025) and atypical angina (29.4% vs. 6.5%, p = 0.016).CONCLUSION: Take-off level, intramural course, and slit-like ostium were the main predictors of abnormal CT-FFR values. Importantly, patients with abnormal CT-FFR values showed a higher prevalence of typical angina and atypical angina, indicating that CT-FFR is a potential tool to gauge the clinical relevance in patients with interarterial R-ACAOS.]]>
Angiography ; Coronary Sinus ; Coronary Vessel Anomalies ; Coronary Vessels ; Diastole ; Hemodynamics ; Humans ; Phenobarbital ; Prevalence ; Retrospective Studies ; ROC Curve ; Systole

OBJECTIVES: To study myocardial perfusion and systolic function in patients with different coronary artery stenosis by myocardial contrast echocardiography (MCE) and two-dimensional speckle tracking imaging (2D-STI). METHODS: MCE, 2D-STI and coronary angiography were conducted in patients with coronary heart disease in our hospital. Myocardial segments were divided into 4 groups according to the degree of coronary artery stenosis: group A (normal group), group B (mild stenosis, 50%-75%), group C (moderate stenosis, 76%-90%) and group D (severe stenosis, 91%-100%). Blood volume, blood flow velocity, blood flow and longitudinal myocardial strain value (SL) in each group were measured by analysis software for MCE and 2D-STI. The differences in blood volume, blood flow velocity, blood flow and SL were evaluated. RESULTS: The blood flow velocity and blood flow in B, C and D groups were decreased gradually, with significant difference (<0.05). There was no significant difference in blood volume, blood flow velocity, blood flow between group A and group B (>0.05). There were significant differences in SL among the 4 groups (<0.05). CONCLUSIONS There is a good correlation between coronary stenosis degree and myocardial perfusion or systolic function. The ability of 2D-STI to detect mild stenosis of coronary artery is better than MCE.
Coronary Circulation ; Coronary Stenosis ; Echocardiography ; Humans ; Myocardium ; Systole

Objective: To explore the association between serum levels of osteopontin (OPN) and systolic pulmonary artery pressure (sPAP) in healthy men following acute high altitude exposure. Methods: According to the inclusion and exclusion criteria, this observational study included 94 male subjects (aged from 18 to 30 years, dwelling in lowland<500 m) who ascended to Litang (4 100 m) from Chongqing (400 m) by bus with a stair-like journey within 7 days in June 2013. Data including basic information, OPN, superoxide dismutase (SOD), and malondialdehyde (MDA) and echocardiographic derived sPAP were collected within 48 hours before ascent and within 2-7 hours after arrival. Accordingly, subjects were divided into 3 groups based on the tertiles of sPAP after acute high altitude exposure: low sPAP group (26.8-32.3 mmHg (1 mmHg=0.133 kPa)) (n=31), middle sPAP group (32.4-37.4 mmHg) (n=32) and high sPAP group (37.5-55.6 mmHg) (n=31). Associations of serum OPN and SOD levels with sPAP were analysed by univariate and multivariate linear regression analysis. Results: After acute high altitude exposure, the levels of sPAP were significantly increased (P<0.001). There were no differences in age, height, weight, body mass index, percent of Han nationality and smoking among 3 subgroups. However, following acute high altitude exposure, the levels of heart rate, systolic and diastolic blood pressure elevated (all P<0.05), whereas the levels of oxygen saturation were reduced in the total subjects and all subgroups (all P<0.05). Moreover, systolic blood pressure of subjects in the high sPAP group was higher than that in low and middle sPAP groups (both P<0.05), and diastolic blood pressure of subjects in high sPAP group was higher than that in low sPAP group (P<0.05). The serum levels of OPN were increased in total cohort(27.9 (22.5,34.0) μg/L vs. 25.6 (18.4, 33.1) μg/L, P<0.05)， and high sPAP group (P<0.05), whereas no differences were found in serum SOD and MDA levels among groups. Furthermore, the serum level of OPN in high sPAP group was higher than that in low sPAP group at high altitude (P<0.05), and there was a trend for decline in SOD level with increasing sPAP (P>0.05). Results from univariable linear regression analysis showed that the serum levels of OPN (r=0.32, P=0.002) and SOD (r=-0.22，P=0.032) were linearly correlated with sPAP in total cohort after high altitude exposure. Multivariate regression analysis showed that the serum levels of OPN(β=0.310，P=0.002) and SOD (β=-0.199，P=0.043) were independently associated with the levels of sPAP at high altitude. Conclusion: After acute high altitude exposure, the serum level of OPN is positively associated with sPAP, suggesting that OPN may be a novel bio-marker for predicting the increase of pulmonary pressure in response to acute high altitude exposure.
Adolescent ; Adult ; Altitude ; Blood Pressure Determination ; Humans ; Male ; Osteopontin ; Pulmonary Artery ; Systole ; Young Adult

Unenhanced echocardiography (UE), commonly used in veterinary practice, is limited by left ventricular (LV) foreshortening and observer dependency. Contrast echocardiography (CE) was used to compare two-dimensional (2D) LV measurements made using UE and 256-row multi-detector computed tomography (MDCT) as a reference standard. Seven healthy beagle dogs were evaluated in this study. Measurements obtained using CE, including LV wall thickness, internal diameter, and longitudinal and transverse length, were significantly greater than those obtained using UE. Measurements of LV internal dimension in diastole (LVIDd) and systole (LVIDs) were significantly larger with CE compared UE. Regardless of the cardiac cycle, LV longitudinal (LVLd and LVLs) and transverse diameter (LVTDd and LVTDs) measurements were significantly different with CE and approximated values from MDCT. Among automatically calculated parameters, LV end-systolic volume and the relative wall thickness were significantly different between UE and CE. In CE, the correlation coefficients of 4 major parameters (r = 0.87 in LVIDd; 0.91 in LVIDs; 0.87 in LVLd; and 0.81 in LVLs) showed higher values compared to the UE (r = 0.68 in LVIDd, 0.71 in LVIDs, 0.69 in LVLd, and 0.35 in LVLs). Inter-observer agreement was highest for MDCT and higher for CE than UE. In conclusion, CE is more accurate and reproducible than UE in assessing 2D LV measurements and can overcome the limitations of UE including LV foreshortening and high observer dependency.
Animals ; Diastole ; Dogs ; Echocardiography ; Multidetector Computed Tomography ; Systole

Background: Pressure overload-induced myocardial hypertrophy is a key step leading to heart failure. Previous cellular and animal studies demonstrated that deteriorated excitation-contraction coupling occurs as early as the compensated stage of hypertrophy before the global decrease in left ventricular ejection fraction (LVEF). This study was to evaluate the cardiac electromechanical coupling time in evaluating cardiac systolic function in the early stage of heart failure. Methods: Twenty-six patients with Stage B heart failure (SBHF) and 31 healthy controls (CONs) were enrolled in this study. M-mode echocardiography was performed to measure LVEF. Tissue Doppler imaging (TDI) combined with electrocardiography (ECG) was used to measure cardiac electromechanical coupling time. Results: There was no significant difference in LVEF between SBHF patients and CONs (64.23 ± 8.91% vs. 64.52 ± 5.90%; P = 0.886). However, all four electromechanical coupling time courses (Qsb: onset of Q wave on ECG to beginning of S wave on TDI, Qst: onset of Q wave on ECG to top of S wave on TDI, Rsb: top of R wave on ECG to beginning of S wave on TDI, and Rst: top of R wave on ECG to top of S wave on TDI) of SBHF patients were significantly longer than those of CONs (Qsb: 119.19 ± 35.68 ms vs. 80.30 ± 14.81 ms, P < 0.001; Qst: 165.42 ± 60.93 ms vs. 129.04 ± 16.97 ms, P = 0.006; Rsb: 82.43 ± 33.66 ms vs. 48.30 ± 15.18 ms, P < 0.001; and Rst: 122.37 ± 36.66 ms vs. 93.25 ± 16.72 ms, P = 0.001), and the Qsb, Rsb, and Rst time showed a significantly higher sensitivity than LVEF (Rst: P =0.032; Rsb: P = 0.003; and Qsb: P = 0.004). Conclusions The cardiac electromechanical coupling time is more sensitive than LVEF in evaluating cardiac systolic function.
Adult ; Echocardiography ; Echocardiography, Doppler ; Electrocardiography ; Female ; Humans ; Male ; Middle Aged ; Systole ; Ventricular Function, Left

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

Extremely low birth weight infants remain at increased risk of intraventricular hemorrhage from the fragile vascular bed of the germinal matrix; the roles of hypotension (ischemia) and reperfusion (hyperemia) in the development of intraventricular hemorrhage are still debated. Cerebrovascular pressure autoregulation protects the brain by maintaining constant cerebral blood flow despite changes in blood pressure. The ontogeny of cerebrovascular pressure autoregulation has not been well established and uncertainty remains about the optimal arterial blood pressure required to support brain perfusion. Another important aspect of premature cerebral hemodynamics is the critical closing pressure––the arterial blood pressure at which cerebral blood flow ceases. Interestingly, in premature infants, the critical closing pressure approximates the mean arterial blood pressure. Often in this unique population, cerebral blood flow occurs only during systole when the diastolic arterial blood pressure is equal to the critical closing pressure. Moreover, the diastolic closing margin, a metric of cerebral perfusion that normalizes diastolic arterial blood pressure to the critical closing pressure, may be a better measure than arterial blood pressure for defining cerebral perfusion in premature infants. Elevated diastolic closing margin has been associated with intraventricular hemorrhage. This review summarizes the current state of understanding of cerebral hemodynamics in premature infants.
Arterial Pressure ; Blood Pressure ; Brain ; Cerebrovascular Circulation ; Hemodynamics ; Hemorrhage ; Homeostasis ; Humans ; Hypotension ; Infant ; Infant, Low Birth Weight ; Infant, Newborn ; Infant, Premature ; Perfusion ; Reperfusion ; Systole ; Uncertainty

Our aim was (1) to determine the within-day and between-day variability of several indices of systolic and diastolic right ventricular (RV) function by using conventional echocardiography and speckle-tracking echocardiography (STE) (Study 1), (2) to quantify these variables in a large healthy canine population (n = 104) with Doppler-derived estimated systolic pulmonary arterial pressure (SPAP) and left ventricular (LV) function, and (3) to establish the corresponding reference intervals (Study 2). For both studies, RV variables included tricuspid annular plane systolic excursion (TAPSE), right fractional area change (RFAC), STE longitudinal systolic strain (StS) of the RV free wall (RVFW) and of the entire RV (i.e., global RV StS), STE longitudinal systolic RVFW strain rate (SRS), and the diastolic early:late strain rate ratio. All but one within- and between-day coefficients of variation (13/14) were < 15%, the lowest being observed for TAPSE (3.6–9.8%), global RV StS (3.8–9.9%), and RVFW StS (3.7–7.3%). SPAP was weakly and negatively correlated with the TAPSE:body weight ratio (r(s) = −0.26, p = 0.01) and RVFW SRS (r(s) = −0.23, p < 0.05). Reference intervals (lower and upper limits with 90% confidence intervals) were provided for all variables. STE provides a non-invasive evaluation of RV function that may be used for clinical investigations in canine cardiology.
Animals ; Arterial Pressure ; Cardiology ; Diastole ; Dogs ; Echocardiography ; Heart ; Myocardium ; Prospective Studies ; Systole ; Ventricular Function, Right