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In this study, two vortex rings composed of upper fluid were continuously ejected vertically downward toward the interface of the two-layer density-stratified fluid. The motion of the vortex rings and behavior of the lower layer fluid were investigated via visualization experiment, and the effect of time interval between the injections of the two vortex rings on the mixing of the density-stratified fluid was investigated. The first emitted vortex ring (VRA) advected vertically downward in the upper layer, passed through the density interface, and then advected in the lower layer. After VRA reached the maximum depth in the lower layer, the upper part of the fluid mass ejected into the upper layer due to buoyancy. The lower fluid was entrained in the upper layer. Subsequently, a new vortex ring (VRC) was generated by the fluid mass ejected in the upper layer and advected vertically upward in the upper layer. The second vortex ring emitted (VRB) collided with the tip of the fluid mass of the VRA ejected from the lower layer. Subsequently, it slightly penetrated the lower layer, rolled up the lower layer fluid into the upper layer, and coalesced with VRC to collapse. In the process of vortex merging, the mixing of the upper and lower layers reached a maximum when the VRA reached the maximum depth. Furthermore, it was clarified that the mixing ability of the upper and lower layers depends on the ejection time interval of the two vortex rings.

Objective To evaluate the time of ureteral ejection of intravenous sodium fluorescein in the assessment of ureteral patency in patients undergoing total laparoscopic hysterectomy (TLH). Material and methods Fifty-four women undergoing TLH were studied in a public teaching hospital in Culiacan, Sinaloa, Mexico. They underwent cystoscopic evaluation of ureteral patency after intravenous administration of 100 mg of sodium fluorescein. The present study analyzed the time elapsed in minutes from the intravenous administration of fluorescein to the outflow of stained urine by one or both ureteral meatus, the degree of urine staining, and the impact of body mass index (BMI) (BMI; normal, overweight, and obesity) on ejection time. Results The overall average time elapsed to visualize the ejection of fluorescein through at least one ureteral meatus was 7.5 minutes [95% confidence interval (CI): 6.3-8.7]. There were no significant differences in the time of ureteral ejection of fluorescein taking BMI into account (p=0.579), with a mean time for normal BMI of 8.1 minutes (95% CI: 5.1-11.2), for overweight of 7.0 minutes (95% CI: 5.5-8.5), and for obesity of 7.8 minutes (95% CI: 5.3-10.3). Conclusion Intravenously administered 10% sodium fluorescein dye is rapidly eliminated and strongly stains urine, which makes it useful for identifying ureteral patency during cystoscopy after TLH. Fluorescein excretion is not affected by patient BMI.

Aims: The assessment of aortic stenosis (AS) severity is still challenging, especially in abnormal hemodynamic conditions. Left ventricular ejection time (LVET) has been historically related to AS severity, but it also depends on heart rate (HR) and systolic function. Our aim was to verify if correcting LVET (LVET index, LVETI) by its determinants is helpful for the assessment of AS severity, irrespective of hemodynamic conditions. Methods and results: We retrospectively studied 152 patients with AS and 378 patients with heart failure and no-AS. At multivariate analysis, LVET (assessed with pulsed-wave Doppler) showed a strong correlation with stroke volume index (SVI) (Beta 0.354; p < 0.001), HR (−0.385; p < 0.001), AS grade (Beta 0.301; p < 0.001) and, less significantly, ejection fraction (LVEF) (Beta 0.108; p = 0.001). AS grade was confirmed to be a major determinant of LVET, irrespective of forward flow (assessed by SVI and transvalvular flow rate) and LVEF (above and below 50%). A regression equation was derived to index LVET (LVETI) to HR and SVI. By using this formula, LVETI detected severe AS more accurately (AUC 0.812, p < 0.001) than LVET alone (AUC 0.755, p for difference = 0.005). Similar results were observed in patients with abnormal flow status. As an exploratory finding, we observed that the highest tertile of LVETI was associated with a higher rate of aortic valve interventions during follow-up. Conclusions: LVETI correlates with AS severity better than uncorrected LVET, independently from hemodynamic conditions, and may help to discriminate severe AS. This finding needs confirmation in larger prospective multicenter studies.

OBJECTIVE: To evaluate fetal lung development using pulmonary artery Doppler in pregnant women who had recovered from COVID-19. METHODS: The prospective case-control study included 41 pregnant women who had recovered from COVID-19 and 43 healthy pregnant women (control group). All the women in the study group had been diagnosed with COVID-19 and had completed a quarantine period. RESULTS: The demographic data of patients were similar in the groups (P > 0.05). Main pulmonary artery peak systolic velocity was higher and pulsatility indices were lower in pregnant women who recovered from COVID-19 compared to the controls (P

Background: Echocardiographic transaortic jet velocity (Vmax), mean pressure gradient (mPG), and aortic valve area (AVA) are routinely measured for severity of aortic stenosis (AS). Additionally, prolonged ejection time (ET), acceleration time (AT), and its ratio AT/ET are also known as indexes of AS severity. However, acoustic window dependency of AT/ET is not well studied. Methods: Eighty-one patients with AS assessed by transaortic jet tracing of all of three approaches (apical 3-chamber (3C), apical 5-chamber (5C), and right parasternal (R)) were included in this study. ET, AT, and AT/ET were measured on continuous Doppler recordings obtained by 3C, 5C, and R approaches. Also, ET and AT were corrected by dividing by (R-R interval)1/2, and they were named as cET and cAT. Results: No differences were observed in cET among 3 approaches. However, cAT was significantly longer in R (115+23 msec: p

Background: Acceleration time (AT)/ejection time (ET) ratio is a marker of aortic valve stenosis (AS) severity and predicts outcome in moderate-severe AS. Methods: We explored the association of increased AT/ET ratio on prognosis in 1530 asymptomatic patients with presumably mild-moderate AS, normal ejection fraction, and without known diabetes or cardiovascular disease. Patients were part of the SEAS study (Simvastatin Ezetimibe Aortic Stenosis). Patients were grouped according to the optimal AT/ET ratio threshold to predict cardiovascular death and heart failure hospitalization. Low-gradient severe AS was identified as combined valve area ≤1.0 cm 2 and mean gradient Results: Higher AT/ET ratio was significantly associated with lower systolic blood pressure, lower left ventricular ejection fraction, lower stress-corrected midwall shortening, low flow, and with higher left ventricular mass and higher peak aortic jet velocity. AT/ET ratio ≥0.32 provided the optimal cutoff for predicting incident cardiovascular death and heart failure hospitalization in the total study sample. In patients with low-gradient severe AS, this threshold was >0.32. AT/ET ratio ≥0.32 had a 79% higher risk of cardiovascular death and heart failure hospitalization (hazard ratio, 1.79 [95% CI, 1.20–2.68]). In patients with low-gradient severe AS, AT/ET ratio >0.32 was associated with a 2-fold higher risk of cardiovascular death and heart failure hospitalization (hazard ratio, 2.15 [95% CI, 1.22–3.77]). Conclusions: In asymptomatic nonsevere AS and low-gradient severe AS, higher AT/ET ratio was associated with increased cardiovascular morbidity and mortality. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT00092677.

Left ventricular systolic function is a good indicator of cardiac function and a powerful predictor of adverse cardiovascular (CV) outcomes. High ratio of pre-ejection period (PEP) to ejection time (ET) is associated with reduced left ventricular systolic function. Brachial PEP (bPEP) and brachial ET (bET) can be automatically calculated from an ankle-brachial index (ABI)-form device and bPEP/bET was recently reported to be a new and useful parameter of cardiac performance. However, there were no studies evaluating the utility of bPEP/bET for prediction of CV and overall mortality in patients with acute myocardial infarction (AMI). We included 139 cases of AMI admitted to our cardiac care unit consecutively. ABI, bPEP, and bET were obtained from the ABI-form device within the 24 hours of admission. There were 87 overall and 22 CV mortality and the median follow-up to mortality event was 98 months. After multivariable analysis, high bPEP/bET was not only associated with increased long-term CV mortality (hazard ratio (HR) = 1.046; 95% confidence interval (CI): 1.005–1.088; P = 0.029), but also associated with long-term overall mortality (HR = 1.023; 95% CI: 1.001–1.045; P = 0.042). In addition, age was also a significant predictor for CV and overall mortality after the multivariable analysis. In conclusion, bPEP/bET was shown to be a significant predictor for CV and overall mortality in AMI patients after multivariable analysis. Therefore, by means of this novel parameter, we could easily find out the high-risk AMI patients with increased CV and overall mortality.

OBJECTIVES: Fetal cardiac function can be evaluated using a variety of parameters. Among these, cardiac cycle time-related parameters, such as filling time fraction (FTF) and ejection time fraction (ETF), are promising but rarely studied. We aimed to report the feasibility and reproducibility of fetal FTF and ETF measurements using pulsed-wave Doppler, to provide reference ranges for fetal FTF and ETF, after evaluating their relationship with heart rate (HR), gestational age (GA) and estimated fetal weight (EFW), and to evaluate their potential clinical utility in selected fetal conditions. METHODS: This study included a low-risk prospective cohort of singleton pregnancies and a high-risk population of fetuses with severe twin-twin transfusion syndrome (TTTS), aortic stenosis (AoS) or aortic coarctation (CoA), from 18 to 41 weeks' gestation. Left ventricular (LV) and right ventricular inflow and outflow pulsed-wave Doppler signals were analyzed, using valve clicks as landmarks. FTF was calculated as: (filling time/cycle time) × 100. ETF was calculated as: (ejection time/cycle time) × 100. Intraclass correlation coefficients (ICC) were used to evaluate the intra- and interobserver reproducibility of FTF and ETF measurements in low-risk fetuses. The relationships of FTF and ETF with HR, GA and EFW were evaluated using multivariate regression analysis. Reference ranges for FTF and ETF were then constructed using the low-risk population. Z-scores of FTF and ETF in the high-risk fetuses were calculated and analyzed. RESULTS: In total, 602 low-risk singleton pregnancies and 54 high-risk fetuses (nine pairs of monochorionic twins with severe TTTS, 16 fetuses with AoS and 20 fetuses with CoA) were included. Adequate Doppler traces for FTF and ETF could be obtained in 95% of low-risk cases. Intraobserver reproducibility was good to excellent (ICC, 0.831-0.905) and interobserver reproducibility was good (ICC, 0.801-0.837) for measurements of all timing parameters analyzed. Multivariate analysis of FTF and ETF in relation to HR, GA and EFW in low-risk fetuses identified HR as the only variable predictive of FTF, while ETF was dependent on both HR and GA. FTF increased with decreasing HR in low-risk fetuses, while ETF showed the opposite behavior, decreasing with decreasing HR. Most recipient twins with severe TTTS showed reduced FTF and preserved ETF. AoS was associated with decreased FTF and increased ETF in the LV, with seemingly different patterns associated with univentricular vs biventricular postnatal outcome. The majority of fetuses with CoA had FTF and ETF within the normal range in both ventricles. CONCLUSIONS: Measurement of FTF and ETF using pulsed-wave Doppler is feasible and reproducible in the fetus. The presented reference ranges account for associations of FTF with HR and of ETF with HR and GA. These time fractions are potentially useful for clinical monitoring of cardiac function in severe TTTS, AoS and other fetal conditions overloading the heart. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

Introduction The ratio of acceleration time to ejection time (AT/ET) is a simple and reproducible echocardiographic parameter that integrates AS severity and its consequences on the LV. The prognostic impact of AT/ET on outcome in patients with SAS and no or mild symptoms has not been investigated. This study sought to determine the prognostic impact of AT/ET on mortality in patients with severe aortic stenosis (SAS), preserved left ventricular ejection fraction (LVEF) and no or only mild symptoms. Method Three hundred and fifty-three patients [median age 79 (71–85), 46% women] with high gradient [mean pressure gradient ≥ 40 mmHg and/or aortic peak jet velocity (Vmax)≥4 m/s] SAS, LVEF ≥ 50% and no or only mild AS symptoms were studied. Patients were retrospectively stratified by AT/ET ≤ or > 0.35. Survival analyses were carried out to study the impact of AT/ET on all-cause mortality. Results During a median follow-up of 39 (23–62) months, 70 patients died. AT/ET > 0.35 was associated with a considerable increased mortality risk after adjustment for established prognostic factors in SAS when the entire follow up (medical and/or surgical management) was considered [adjusted HR 2.54 (95%CI,1 .47–4.37); P 0.35 improved the predictive performance of multivariable models including established risk factors in SAS as indicated by better global model fit, reclassification, and discrimination. After propensity score matching (n = 236), increased risk of mortality persisted for patients with AT/ET > 0.35 compared with those with AT/ET ≤ 0.35 [adjusted HR 2.67 (95% CI, 1.45–4.92); P = 0.002] ( Fig. 1 ). Conclusion AT/ET > 0.35 is a strong predictor of outcome in patients with SAS and no or only mild symptoms and identifies a subgroup of patients at higher risk of death who may derive benefit from earlier aortic valve replacement.

Introduction Acceleration/ejection time (AT/ET) ratio is a marker of aortic stenosis (AS) severity, and a predictor of outcome in severe AS. The importance of ejection dynamics in mild and moderate AS has been less investigated. Purpose To investigate the impact of increased AT/ET ratio on prognosis in patients with mild-moderate AS. Methods Data from 1635 patients with asymptomatic mild-moderate AS with preserved ejection fraction enrolled in the Simvastatin and Ezetimibe in Aortic Stenosis study was analysed. Covariates of higher AT/ET ratio was identified in linear regression analysis. Outcome was assessed in Cox regression analyses and reported as hazard ratio (HR) and 95% confidence interval (CI) per 1 standard deviation (SD) higher AT/ET ratio. Median follow-up time was 4 years. Results The total study population included 38% female, mean age 67 years and average peak aortic jet velocity was 3.02 m/s. Higher AT/ET ratio was significantly associated with lower ejection fraction, higher LV mass, higher aortic jet velocity, lower systolic blood pressure, low stroke volume index and lower stress-corrected midwall shortening (all p Conclusion In asymptomatic mild-moderate AS patients free from diabetes and known cardiovascular disease, higher AT/ET ratio was associated with increased risk for major cardiovascular events, cardiovascular death and hospitalization for heart failure and all-cause mortality independent of traditional risk markers. Funding Acknowledgement Type of funding source: None

Langevin dynamics simulations are performed to investigate ejection dynamics of spherically confined flexible polymers through a pore. By varying the chain length $N$ and the initial volume fraction $\phi_0$ of the monomers, two scaling behaviors for the ejection velocity $v$ on the monomer number $m$ in the cavity are obtained: $v \sim m^{1.25}\phi_0^{1.25}/N^{1.6}$ for large $m$ and $v \sim m^{-1.4}$ as $m$ is small. A robust scaling theory is developed by dividing the process into the confined and the non-confined stages, and the dynamical equation is derived via the study of energy dissipation. After trimming the prior stage related to the escape of the head monomer across the pore, the evolution of $m$ is shown to be well described by the scaling theory. The ejection time exhibits two proper scaling behaviors: $N^{2/(3\nu)+y_1}\phi_0^{-2/(3\nu)}$ and $N^{2+y_2}$ under the large and small $\phi_0$- or $N$-conditions, respectively, where $y_1=1/3$, $y_2=1-\nu$, and $\nu$ is the Flory exponent., Comment: 5 pages, 5 figures, accepted for publication in PRL

AIMS Worsening heart failure (HF) is associated with shorter left ventricular systolic ejection time (SET), but there are limited data describing the relationship between SET and clinical outcomes. Thus, the objective was to describe the association between SET and clinical outcomes in an ambulatory HF population irrespective of ejection fraction (EF). METHODS AND RESULTS We identified ambulatory patients with HF with reduced EF (HFrEF) and HF with preserved EF (HFpEF) who had an outpatient transthoracic echocardiogram performed between August 2008 and July 2010 at a tertiary referral centre. Multivariable logistic regression was used to evaluate the association between SET and 1-year outcomes. A total of 545 HF patients (171 HFrEF, 374 HFpEF) met eligibility criteria. Compared with HFpEF, HFrEF patients were younger [median age 60 years (25th-75th percentiles 50-69) vs. 64 years (25th-75th percentiles 53-74], with fewer females (30% vs. 56%) and a similar percentage of African Americans (36% vs. 35%). Median (25th-75th percentiles) EF with HFrEF was 30% (25-35%) and with HFpEF was 54% (48-58%). Median SET was shorter (280 ms vs. 315 ms, P

An increase in the ratio of the brachial pre-ejection period to brachial ejection time [pre-ejection period (PEP)/ET] is correlated with a decrease of left ventricular ejection fraction (LVEF). The current study was designed to test the hypothesis that the change value (Δ) of PEP/ET is a useful indicator of Δ LVEF in patients with left ventricular systolic dysfunction.We consecutively enrolled 104 patients with left ventricular systolic dysfunction (LVEF < 45%). PEP/ET, B-type natriuretic peptide (BNP), and LVEF were evaluated at baseline and at 6-month follow-up. Compared with the baseline measurements, the 6-month values of ΔLVEF, ΔBNP, and ΔPEP/ET were 9.8% ± 9.0% (from 36.3% ± 9.2% to 46.3% ± 12.5%, P < 0.001), -168.5 ± 255.4 (from 271.4 ± 282.5 to 104.1 ± 129.6, P < 0.001), and -0.060 ± 0.069 (from 0.413 ± 0.097 to 0.358 ± 0.079, P < 0.001), respectively. There were significant correlations between LVEF and PEP/ET and between LVEF and BNP in both the initial (r = -0.316, P = 0.001 and r = -0.598, P < 0.001, respectively) and 6-month follow-up (r = -0.307, P = 0.003 and r = -0.701, P < 0.001, respectively). The Steiger's Z test showed that BNP had a significantly stronger correlation with LVEF compared with the correlations between LVEF and PEP/ET in both the initial and 6-month studies (Z = 2.471, P = 0.013 and Z = 3.575, P < 0.001, respectively). There were also significant correlations between ΔLVEF and ΔPEP/ET (r = -0.515, P < 0.001) and between ΔLVEF and ΔBNP (r = -0.581, P < 0.001); however, there was no difference between the correlations for ΔLVEF and ΔPEP/ET versus ΔLVEF and ΔBNP (Steiger's Z = 0.600, P = 0.545).In patients with left ventricular systolic dysfunction not only ΔBNP but also ΔPEP/ET could be a simple indicator of predicting change of LVEF.

An increased acceleration time to ejection time (AT/ET) ratio is associated with increased mortality in patients with aortic stenosis (AS).To identify the factors associated with an increased AT/ET ratio.The relationships between the AT/ET ratio and clinical and Doppler echocardiographic variables of interest in the setting of AS were analysed retrospectively in 1107 patients with AS and preserved left ventricular (LV) ejection fraction (LVEF). The computed tomography aortic valve calcium (CT-AVC) score was studied in a subgroup of 342 patients.In the univariate analysis, the AT/ET ratio was found to correlate with peak aortic jet velocity (r=0.57; P0.0001), mean pressure gradient (r=0.60; P0.0001), aortic valve area (r=-0.50; P0.0001) and CT-AVC score (r=0.24; P0.0001). The AT/ET ratio had good accuracy in predicting a peak aortic jet velocity≥4 m/s, a mean pressure gradient≥40mmHg and an aortic valve area≤1.0cmThe AT/ET ratio is related to echocardiographic and CT-AVC indices of AS severity. However, multiple intricate factors beyond the haemodynamic and anatomical severity of AS influence the AT/ET ratio, including LV geometry, function and systolic blood pressure. These findings should be considered when assessing the AT/ET ratio in patients with AS and preserved LVEF.

Background Acceleration time to ejection time ratio (AT/ET) prolongation is associated with increased mortality in patients with aortic stenosis (AS). Purpose To identify the determinants associated with increased AT/ET. Methods The relationships between AT/ET ratio, clinical and Doppler echocardiographic variables of interest in the setting of AS were studied in 1107 patients with AS and preserved left ventricular (LV) ejection fraction (EF), with Computed Tomography – Aortic Valve Calcium (CT-AVC) score studied in a subgroup of 342 patients. Results In univariate analysis, AT/ET ratio did correlate with aortic peak velocity (Vmax, r=0.57, p Conclusion AT/ET ratio is related to echocardiographic and CT-AVC indices of AS severity. However, multiple intricate factors beyond hemodynamic and anatomic severity of AS influence AT/ET ratio including LV geometry, function and SBP. These findings should be considered when assessing AT/ET in patients with AS and preserved LVEF. Acknowledgement/Funding Local funding

PubMed ID: 29212398, Objective: We aimed with this study to evaluate the role of pulmonary artery acceleration time to ejection time ratio (PATET) in the prediction of respiratory distress syndrome (RDS) in preterm neonates. Materials and methods: In this prospective cohort study, 105 singleton pregnant women with no congenital abnormalities and pregnancy complications who delivered before 37 weeks of gestational age were included. All the patients underwent ultrasound examination to obtain fetal pulmonary artery Doppler. 15 patients were excluded from the study as they did not give birth within 3 days subsequent to ultrasound examination, or inadequate Doppler measurements. After delivery the neonates were grouped according to diagnosis of RDS as RDS + and RDS-. Results: One hundred five women met the inclusion criteria. Regarding the Doppler findings; only the PATET ratio was significantly different between the groups (0.2965 ± 0.042 versus 0.386 ± 0.068 p

The aim of the study was to evaluate the changes in approximate entropy (ApEn), used to quantify the amount of regularity and the unpredictability of fluctuations over hemodynamic traces before (0 mmHg) lower body negative pressure (LBNP) and during the first part of the test (-15 mm Hg) in 13 subjects with high (HT) and 11 of low (LT) tolerance to LBNP. We intended to know if ApEn calculated for HT and LT groups are significantly different. 24 healthy, untrained male subjects (age:20.8±0.9 yrs, height: 176.9±4.3 cm, body mass: 74.2±7.1 kg) were submitted to graded LBNP (−15, −30 and −50 mmHg) lasting 10 minutes for each load. The length of RR interval (RR), stroke volume (SV) and ejection time (ET) were determined basing on ECG and first derivative (dz/dt) of impedance cardiography (ICG) traces. Analysis were carried out for unprocessed dz/dt waveform and for hemodynamic parameters time series (RR, SV, ET) by determining ApEn using Pincus approach. No differences in ApEn were found between LT and HT for raw dz/dt traces and RR, SV, ET time series. ApEn for RR, SV and ET were similar in both periods. ApEn seems to be not suitable for predicting the outcome of LBNP test.

For the production of the low-caloric gluten-free cookies, the fat content was reduced by 50, 60 and 70% in the cookie formula. As the fat level decreased, the hardness of the gluten-free dough increased, and the ejection time of the gluten-free dough rose. The texture analysis showed an increase of the dough hardness. The fat replacing with an equal amount of inulin to some extent reduced the consistency of the dough and its hardness, and its cohesive, elastic and adhesive properties increased. The effect of fat reduction negatively affected the texture of gluten-free cookies. The research showed that the texture of gluten-free cookies is highly dependent on the texture of the gluten-free dough. In addition to the fact that fat is responsible for the dough softness and the cookies crisp texture, it also gives an aroma, taste, mouthfeel and general impression to the finished product. The texture of the cookies improved significantly when the fat was replaced by inulin. Accordingly, the quality indexes of the gluten-free cookies could be significantly improved by the fat replacing with inulin.

Accurate assessment of aortic stenosis (AS) severity is essential in management of the disease. Prior studies have demonstrated that ejection dynamics, particularly the ratio of acceleration time (AT) to ejection time (ET) can be used to assess severity. The aim of this study was to evaluate the

Color Tissue Doppler imaging (TDI) M-mode through the mitral leaflet is an easy and precise method to obtain the cardiac time intervals including the isovolumic contraction time (IVCT), isovolumic relaxation time (IVRT) and ejection time (ET) (Figure 1a). Whether the cardiac time intervals can be

PurposeThe pre-ejection period-derived myocardial performance index measured from tissue Doppler echocardiography (PEPa-derived MPI) was reported to be associated with left ventricular systolic and diastolic function in atrial fibrillation (AF). However, its relationship with cardiovascular outcomes in AF has never been evaluated. This study sought to examine the ability of PEPa-derived MPI in predicting adverse cardiovascular events in AF patients.MethodsIn 196 persistent AF patients, we performed comprehensive echocardiography with measurement of PEPa-derived MPI using index beat method. The index beat was defined as the beat following the nearly equal preceding (RR1) and pre-preceding (RR2) intervals. The cycle length of index beat and RR1 and RR2 must be >500ms and the difference between RR1 and RR2 must be

The aim of this study was to develop a Matlab programme for quantitative evaluation and graphical presentation of haemodynamic variability parameters calculated from electrocardiography (ECG) and impedance cardiography (ICG) signals. We also sought to identify and compare patterns of variability in healthy subjects (N) and subjects with atrial fibrillation (AF). We analysed 3000 seconds of ECG and ICG signals acquired continuously during overnight, home recordings of six healthy male subjects (20–22, group N) and five male patients with atrial fibrillation (ages 56–78, group AF). Haemodynamic variability was determined using standard deviation and indices describing asymmetry of stroke volume, systolic time intervals (STI), and their derivatives. Stroke volume (SV), amplitude of impedance signal (dz/dtmax), ejection time (ET) and pre-ejection period (PEP) were calculated automatically. The standard deviation (SD) of SV varied in the range of 9–16 ml in normal subjects, versus 12–39 ml in AF subjects. SD for ET was 14–42 ms for N and 31–68 ms for AF. PEP SD varied 8–33 ms for N and 12–38 ms for AF. Preliminary results show that the patterns of haemodynamic variability in AF patients differed from those observed in non-patients for most of the analysed indices.

Dissertação de Mestrado Integrado em Medicina Veterinária Nos animais de companhia, a hipertensão pulmonar (HP) é uma afeção emergente, cuja deteção tem vindo a aumentar nos últimos anos, devido ao aumento do uso de ecografia cardíaca como exame complementar de diagnóstico. Actualmente, a análise da velocidade do fluxo de regurgitação da válvula tricúspide é o método estandardizado. Neste estudo, 39 cães da raça Yorkshire terrier, onde ainda não está descrita a doença, foram submetidos a uma ecografia cardíaca e divididos em grupo de teste e grupo de controlo, de acordo com a presença ou não de HP. As medidas ecográficas obtidas foram utilizadas para comparação. Verificou-se diferenças significativas entre os grupos no tempo de aceleração (TA) e no rácio de tempo de aceleração sobre o tempo de ejeção (TA:TE) do fluxo da válvula pulmonar. Estas medidas foram submetidas a duas análises estatísticas: a ROC (Receiver Operating Charateristic) e a árvore de decisão Fast and Frugal, sendo que ambas obtiveram resultados promissores. Nas conclusões deste estudo, chegou-se à compreensão de que a hipertensão pulmonar carece de um maior estudo em cães raças pequenas como o Yorkshire terrier e a inclusão de TA e TA:TE no diagnóstico pode melhorar a deteção de HP, com maior relevância para o seu uso numa árvore Fast and Frugal. ABSTRACT - Pulmonary Hypertension: A study regarding cardiac ultrasonographic measures in a sample of 39 Yorkshire terrier dogs - In small animals, pulmonary hypertension (PH) is an emerging disease, whose detection has risen in later years, due to the increase of cardiac ultrasound exams being performed has a diagnostic complimentary exam. Nowadays, the analysis of the velocity of the tricuspid regurgitation flow is the standard method. In this study, 39 dogs of the Yorkshire terrier breed, which hasn’t been described regarding this disease, were submitted to a cardiac ultrasound and divided into experimental group and control group, accordingly confirmed presence of PH or not. The ultrasonographic measures obtained were used for comparison. Significant differences were identified between groups concerning acceleration time (AT) and acceleration time to ejection time ratio (AT:ET) of the pulmonary valve flow. These measures were submitted to two statistical analyses: ROC (Receiver Operating Characteristic) and Fast and Frugal decision tree, in which both have promising results. In conclusion, it was clear that pulmonary hypertension lacks more thorough studies in small breeds like the Yorkshire terrier and the inclusion of AT and AT:ET in diagnosis may improve PH detection, with greater focus on its use with Fast and Frugal tree. N/A

Introduction Acceleration time to ejection time ratio (AT/ET) prolongation is associated with increased mortality in patients with aortic stenosis (AS). We aimed at evaluating the determinants associated with increased AT/ET. Method The relationships between AT/ET ratio, clinical and Doppler echocardiographic variables of interest in the setting of AS were studied in 1107 patients with AS and preserved left ventricular (LV) ejection fraction (EF), with Computed Tomography–Aortic Valve Calcium (CT-AVC) score studied in a subgroup of 342 patients. Results In univariate analysis, AT/ET ratio did correlate with aortic peak velocity (Vmax, r = 0.57, P Conclusion AT/ET ratio is related to echocardiographic and CT-AVC indices of AS severity. However, multiple intricate factors beyond hemodynamic and anatomic severity of AS influence AT/ET ratio including LV geometry, function and SBP. These findings should be considered when assessing AT/ET in patients with AS and preserved LVEF.

ObjectivesWe sought to evaluate whether ejection dynamics, particularly acceleration time (AT) and the ratio of AT to ejection time (ET), can differentiate prosthetic aortic valve (PAV) stenosis from controls and prosthesis–patient mismatch (PPM).BackgroundDiagnosing PAV stenosis, especially in mechanical valves, may be challenging and has significant clinical implications.MethodsDoppler echocardiography was quantitated in 88 patients with PAV (44 mechanical and 44 bioprosthetic; age 63 ± 16 years; valve size range 18 to 25 mm) of whom 22 patients had documented PAV stenosis, 22 had PPM, and 44 served as controls. Quantitative Doppler parameters included ejection dynamics (AT, ET, and AT/ET) and conventional PAV parameters.ResultsPatients with PAV stenosis had significantly lower effective orifice area (EOA) values and higher gradients compared with controls and PPM. Flow ejection parameters (AT and AT/ET) were significantly longer in the stenotic valves compared with PPM and controls (respective values for AT: 120 ± 24 ms, 89 ± 16 ms, and 71 ± 15 ms; for AT/ET: 0.4, 0.32, and 0.3, p ≤ 0.001). Patients with PPM had gradients and ejection dynamics that were intermediate between normal and stenotic valves. Receiver-operator characteristic (ROC) curve analysis showed that AT and AT/ET discriminated PAV stenosis from PPM and controls (area under ROC curve = 0.92 and 0.88, respectively). Combining AT with the conventional Doppler velocity index gave the highest area under the curve of 0.98 but was not statistically different from that of AT alone (p = 0.12). A cutoff of AT = 100 ms had a sensitivity and specificity of 86% for identifying PAV stenosis; for an AT/ET = 0.37, the sensitivity and specificity were 96% and 82%, respectively. Analysis by valve type (mechanical and biological) revealed similar results; however, biological valves had slightly higher areas under the curve for all systolic time intervals.ConclusionsEjection dynamics through PAV, particularly AT and AT/ET, are reliable angle-independent parameters that can help evaluate valve function and identify PAV stenosis.

Objective To assess the learning curve for measurement of the fetal modified myocardial performance index (MPI). Methods Three trainees with the theoretical knowledge of but without prior experience in performing MPI measurement were selected. Each trainee and one experienced examiner measured MPI in a cohort of 90 consecutive fetuses. The average difference between the three trainees and the expert in the MPI measurements was calculated; a difference below 10% was considered to indicate an accurate measurement. Individual and averaged learning curves were delineated using cumulative sum analysis (CUSUM). Results The gestational age at evaluation ranged from 20 + 4 to 41 + 4 (mean, 33 + 3) weeks. The CUSUM plots demonstrated that, on average, competence in performing fetal MPI measurement was achieved by 65 cases. The average number of attempts to achieve competence were 42, 77 and 83 for the ejection time, isovolumetric contraction time and isovolumetric relaxation time, respectively. Conclusions Evaluation of fetal MPI by an inexperienced trainee requires on average 65 measurements to achieve competence. Copyright © 2011 ISUOG. Published by John Wiley & Sons, Ltd.

SummaryPurposeTo determine the acute change in cardiac performance after intravenous immunoglobulin infusion (IVIG) in patients with acute Kawasaki disease (KD).Materials and methodsSubjects were 33 patients with KD who were treated with IVIG 2g/kg and recovered without coronary artery lesion and 27 controls. Subjects underwent combined two-dimensional, Doppler, and tissue Doppler echocardiographic (TDI) studies. In KD, these echocardiographic studies were performed before IVIG, 48h after IVIG, and in convalescence. Echocardiographic variables were compared between KD and controls as well as among 3 time points in KD.ResultsBefore IVIG, KD showed significantly higher peak aortic velocity and shorter aortic ejection time as results of tachycardia and significantly lower E′ (p

Avaliaram-se o índice de performance do miocárdio (IPM) e outros índices ecoDopplercardiográficos de função ventricular em cães de duas raças de diferentes biotipos. Foram utilizados 24 cães da raça Schnauzer Miniatura, com média de peso de 8,4±1,6kg, e 24 cães da raça Boxer, com média de peso de 25,1±2,6kg. O IPM na raça Schnauzer Miniatura foi 0,32 e na raça Boxer 0,48. Os valores do IPM, dos índices de fase de ejeção, do período de pré-ejeção, da relação período de pré-ejeção/período de ejeção e do tempo de desaceleração da onda E do fluxo mitral diferiram entre as duas raças. Observou-se correlação entre o peso corporal e esses índices, e o peso corporal foi considerado a principal característica racial responsável pelas diferenças observadas. O tempo de ejeção (r=-0,51), o período de pré-ejeção (r=-0,44) e o tempo de relaxamento isovolumétrico (r=-0,38) foram os únicos parâmetros a apresentar correlação com a freqüência cardíaca (FC). O uso da relação período de pré-ejeção/tempo de ejeção e do tempo de ejeção corrigido pela freqüência cardíaca diminui o efeito da FC sobre esses parâmetros.

Objective In aortic valve regurgitation and aortic dilatation, preservation of the aortic valve is possible by means of root remodeling (Yacoub procedure) or valve reimplantation (David procedure). In vivo studies suggest that reimplantation might substantially influence aortic valve-motion characteristics. Evaluation of aortic valve movement in vivo, however, is technically limited and is difficult to standardize. We evaluated the aortic valve-motion pattern echocardiographically in vitro after reimplantation and remodeling. Methods By using aortic roots of house pigs (aortoventricular diameter, 22 mm) a Yacoub procedure (22-mm graft; group Y, n = 5) or a David I procedure (24-mm graft; group D, n = 5) was performed. Roots after supracommissural replacement (22-mm graft; group C, n = 5) served as control valves. In an electrohydraulic, computer-controlled pulse duplicator the valves were tested at flows of 2, 4, 7, and 9 L/min. Echocardiographically assessed parameters were rapid valve-opening velocity, slow valve-closing velocity, rapid valve-closing velocity, rapid valve-opening time, rapid valve-closing time, ejection time, maximum valve opening, slow valve-closing displacement, and maximum flow velocity. Results Mean rapid valve-opening velocity and mean rapid valve-closing velocity at a cardiac output of 2 to 9 L/min were fastest in group D (rapid valve-opening velocity: 69 ± 10 cm/s [group D] vs 39 ± 4 cm/s [group Y] vs 42 ± 4 cm/s [group C], P = .0041; rapid valve-closing velocity: 22 ± 2 cm/s [group D] vs 16 ± 2 cm/s [group Y] vs 17 ± 1 cm/s [group C], P = .0272), and slow valve-closing velocity was slowest in group D (0.2 ± 0.1 cm/s [group D] vs 1.0 ± 0.3 cm/s [group Y] vs 0.6 ± 0.1 cm/s [group C], P = .0063). With increasing cardiac output, the difference in rapid valve-opening velocity between the groups increased, the difference in slow valve-closing velocity remained unchanged, and the difference in rapid valve-closing velocity decreased. Conclusions In this standardized experimental setting remodeling of the aortic valve provides significantly smoother valve movements. This might contribute to preservation of a better valve performance during long-term follow-up.

Accepted: 2003-12-15, 資料番号: SA1003966000

The present study aimed to evaluate the development of pulmonary hypertension by serial echocardiography, including measurements of pulmonary artery (PA) flow velocities, and correlate echocardiographic indices with pathological findings in rats administered monocrotaline (MCT). MCT (60 mg/kg body weight) or physiologic saline was administered to a total of 9 male Wistar rats at the age of 4 weeks (MCT group: n = 4, control group: n = 5, respectively). Echocardiography was performed serially until the age of 8 weeks. The ratio of right ventricular (RV) outflow tract dimensions to aortic dimensions increased progressively in the MCT group and became significantly greater than that of the control group after the age of 6 weeks. Peak PA velocity (Peak V) in the MCT group was significantly less than that of the control group at the ages of 7 and 8 weeks. The ratio of acceleration time to ejection time (AT/ET) in PA flow waveforms declined progressively and was significantly less than that of the control group after the age of 6 weeks. The ratio of RV weight to body weight (RVW/BW) in the MCT group was significantly greater than that of the control group. Both AT/ET ratio and Peak V were significantly inversely correlated with RVW/BW ratio. Furthermore, these echocardiographic findings were also significantly inversely correlated with the mean cross-sectional RV myocyte area. In conclusion, the progressive development of pulmonary hypertension leading to RV hypertrophy can be evaluated appropriately by echocardiography including PA flow Doppler indices in rats.