Pulsed Doppler Measurements Research Articles

Evaluation of lateral sagittal infraclavicular block according to inferior vena cava collapsibility index (VCI-CI): An observational study.

Depending on the total amount of fluid, changes occur in the amount of fluid in the peripheral area. The aim of this study was to observe the differences caused by hemodynamic changes after lateral sagittal infraclavicular block (LS-ICB) according to the inferior vena cava collapsibility index (VCI-CI). In this prospective, observational study (Clinical Trial Number: NCT05968105), patients undergoing elective hand and wrist surgery with LS-ICB were classified according to VCI-CI, with Group 1 defined as inferior vena cava (VCI) diameter < 1.5 cm and VCI-CI > 50% and Group 2 defined as VCI diameter > 1.5 cm and VCI-CI < 50%. Groups were compared for demographic characteristics, defined durations, rescue analgesics, and complications. Continuous hemodynamic parameters and pulsed wave Doppler were evaluated within groups. Demographic characteristics and time periods were comparable between the groups. Hemodynamic parameters and pulsed wave Doppler measurements showed no significant differences. However, while Group 1 remained consistent, Group 2 exhibited differences in axillary artery diastolic diameter and axillary artery contractility index. A significant statistical difference was observed in Group 1 for the perfusion index at 30 minutes and postoperatively, whereas Group 2 remained consistent. The dosage and number of patients requiring rescue analgesics were similar across both groups, and no complications were reported. Blood flow increased after LS-ICB without a corresponding increase in axillary artery diameter. Group 1 showed a tendency toward a lower perfusion index in the postoperative period.

Automatic Max-Likelihood Envelope Detection Algorithm for Quantitative High-Frame-Rate Ultrasound for Neonatal Brain Monitoring

Background and AimPostoperative brain injury in neonates may result from disturbed cerebral perfusion, but accurate perioperative monitoring is lacking. High frame rate (HFR) cerebral ultrasound could visualize and quantify flow in all detectable vessels using spectral Doppler; however, automated quantification in small vessels is challenging due to low signal amplitude. We have developed an automatic envelope detection algorithm for HFR pulsed wave spectral Doppler signals, enabling neonatal brain quantitative parameter maps during and after surgery. MethodsHFR ultrasound data from high-risk neonatal surgeries were recorded with a custom HFR mode (framerate 1000Hz) on a Zonare ZS3 system. A pulsed wave Doppler spectrogram was calculated for each pixel containing blood flow in the image, and spectral-peak velocity was tracked using a max-likelihood estimation algorithm of signal and noise regions in the spectrogram, where the most likely cross-over point marks the blood flow velocity. The resulting peak-systolic velocity (PSV), end-diastolic velocity (EDV) and resistivity index (RI) were compared with other detection schemes, manual tracking, and RI from regular pulsed wave Doppler measurements in 10 neonates. ResultsEnvelope detection was successful in both high- and low-quality arterial and venous flow spectrograms. Our technique had the lowest root mean square error for EDV, PSV, and RI (0.46cm/s, 0.53 cm/s, and 0.15, respectively) when compared with manual tracking. There was good agreement between the clinical pulsed wave Doppler RI and HFR measurement with a mean difference of 0.07. ConclusionThe max-likelihood algorithm is a promising approach for accurate, automated cerebral blood flow monitoring with high-frame rate imaging in neonates.

RESPIRATORY VARIABILITY OF VALVULAR PEAK SYSTOLIC VELOCITY AS A NEW INDICATOR OF FLUID RESPONSIVENESS IN PATIENTS WITH SEPTIC SHOCK.

Objective: The aim of this study was to evaluate the reliability and feasibility of pulse Doppler measurements of peak velocity respiratory variability of mitral and tricuspid valve rings during systole as new dynamic indicators of fluid responsiveness in patients with septic shock. Methods: Transthoracic echocardiography (TTE) was performed to measure the respiratory variability of aortic velocity-time integral (∆VTI), respiratory variability of tricuspid annulus systolic peak velocity (∆RVS), respiratory variability of mitral annulus systolic peak velocity (∆LVS), and other related indicators. Fluid responsiveness was defined as a 10% increase in cardiac output after fluid expansion, assessed by TTE. Results: A total of 33 patients with septic shock were enrolled in this study. First, there was no significant difference in the population characteristics between the fluid responsiveness positive group (n = 17) and the fluid responsiveness negative group (n = 16) ( P > 0.05). Second, Pearson correlation test showed that ∆RVS, ∆LVS, and TAPSE with the relative increase in cardiac output after fluid expansion ( R = 0.55, P = 0.001; R = 0.40, P = 0.02; R = 0.36, P = 0.041). Third, multiple logistic regression analysis demonstrated that ∆RVS, ∆LVS, and TAPSE were significantly correlated with fluid responsiveness in patients with septic shock. Fourth, receiver operating characteristic (ROC) curve analysis revealed that ∆VTI, ∆LVS, ∆RVS, and TAPSE had good predictive ability for fluid responsiveness in patients with septic shock. The area under the curve (AUC) of ∆VTI, ∆LVS, ∆RVS, and TAPSE for predicting fluid responsiveness was 0.952, 0.802, 0.822, and 0.713, respectively. The sensitivity (Se) values were 1.00, 0.73, 0.81, and 0.83, whereas the specificity (Sp) values were 0.84, 0.91, 0.76, and 0.67, respectively. The optimal thresholds were 0.128, 0.129, 0.130, and 13.9 mm, respectively. Conclusion: Tissue Doppler ultrasound evaluation of respiratory variability of mitral and tricuspid annular peak systolic velocity could be a feasible and reliable method for the simple assessment of fluid responsiveness in patients with septic shock.

Helical toroid phantom for 3D flow imaging investigations

The medical physics community has hitherto lacked an effective calibration phantom to holistically evaluate the performance of three-dimensional (3D) flow imaging techniques. Here, we present the design of a new omnidirectional, three-component (3-C) flow phantom whose lumen is consisted of a helical toroid structure (4 mm lumen diameter; helically winded for 5 revolutions over a torus with 10 mm radius; 5 mm helix radius). This phantom’s intraluminal flow trajectory embraces all combinations of x, y, and z directional components, as confirmed using computational fluid dynamics (CFD) simulations. The phantom was physically fabricated via lost-core casting with polyvinyl alcohol cryogel (PVA) as the tissue mimic. 3D ultrasound confirmed that the phantom lumen expectedly resembled a helical toroid geometry. Pulsed Doppler measurements showed that the phantom, when operating under steady flow conditions (3 ml s−1 flow rate), yielded flow velocity magnitudes that agreed well with those derived from CFD at both the inner torus (−47.6 ± 5.7 versus −52.0 ± 2.2 cm s−1; mean ± 1 S.D.) and the outer torus (49.5 ± 4.2 versus 48.0 ± 1.7 cm s−1). Additionally, 3-C velocity vectors acquired from multi-angle pulsed Doppler showed good agreement with CFD-derived velocity vectors (<7% and 10° difference in magnitude and flow angle, respectively). Ultrasound color flow imaging further revealed that the phantom’s axial flow pattern was aligned with the CFD-derived flow profile. Overall, the helical toroid phantom has strong potential as an investigative tool in 3D flow imaging innovation endeavors, such as the development of flow vector estimators and visualization algorithms.

Follow-up after carotid endarterectomy and stenting: What to look for and why

Duplex ultrasound testing after open or endovascular extracranial carotid artery interventions is a clinical practice guideline with a strong recommendation from the Society for Vascular Surgery. Neurologic outcomes are improved by the recognition of repair site stenosis or atherosclerotic disease progression in the unoperated carotid artery. The benefit of surveillance outweighs its risk because duplex testing is free of complications and accurate in the detection of internal carotid artery (ICA) stenosis or occlusion. Surveillance for >70% ICA stenosis is recommended within 30 days of the procedure, then every 6 months for 2 years, and annually thereafter. Repair site and contralateral ICA stenosis classification should be based on angle-corrected pulsed Doppler measurements of peak systolic velocity (PSV), end-diastolic velocity (EDV), and the ratio of PSV at the stenosis to a proximal, nondiseased common carotid artery (CCA) segment (ICA/CCA ratio). Interpretation criteria of PSV >300 cm/s, EDV >125 cm/s, and ICA/CCA ratio >4 predicts >70% repair site stenosis. Endovascular intervention is recommended for a carotid repair site stenosis based on the occurrence of an ipsilateral neurologic event and appropriate anatomy for angioplasty. For asymptomatic restenosis, intervention is based on stenosis progression to elevated PSV and EDV >70% stenosis threshold values and the patient is deemed high risk for stroke due to contralateral ICA occlusion or incomplete functional patency of the circle of Willis.

Are there changes to regional tissue oxygenation and circulation following umbilical artery catheter placement? A prospective cohort study in newborn infants.

The use of umbilical arterial catheters (UACs) is a standard of care in monitoring critically unwell infants. Serious vascular complications are rare but when they do occur, they can be associated with significant morbidity, risking limb loss or even death. Near infra-red spectroscopy has the potential to monitor limb perfusion. Our study investigates changes in tissue oxygenation and perfusion in the abdominal and leg circulation following UAC insertion. A prospective observational study performing ultrasound pulsed Doppler measurements in the coeliac, superior mesenteric artery, renal arteries and the femoral arteries as well as near infrared spectroscopy measurements of both thighs at three time points (immediately before = Time 1, 1 h after = Time 2 and 24 h after UAC insertion = Time 3). We monitored 30 infants, the mean gestational age was 30 weeks (24-41) and the mean birthweight was 1720 g (600-4070 g). We observed statistically significant changes (P < 0.05) in pulse Doppler measurements in coeliac (mean peak systolic velocity (PSV): Time 1 = 70.51, Time 2 = 61.75; resistive index (RI): Time 1 = 0.75, Time 2 = 0.67), superior mesenteric (PSV: Time 1 = 41.72, Time 2 = 36.10; RI: Time 1 = 0.92, Time 2 = 0.87), renal (same side end-diastolic velocity: Time 1 = 1.98, Time 2 = 3.80; RI: Time 1 = 0.93, Time 2 = 0.87; opposite side end-diastolic velocity: Time 1 = 2.62, Time 2 = 3.84; RI: Time 1 = 0.92, Time 2 = 0.85) and femoral arteries (same side PSV: Time 1 = 72.75, Time 2 = 62.18; opposite side PSV: Time 1 = 81.89, Time 2 = 62.74). Tissue oxygenation in lower limbs remained unaffected (same side (mean): Time 1 = 68.59, Time 2 = 68.99, Time 3 = 66.40, opposite side: Time 1 = 67.72, Time 2 = 66.92, Time 3 = 65.40). All infants on clinical examination had normal lower limb perfusion, lower limb arterial pulses and normal perfusion to the gluteal region before and after insertion of UAC. While sub-clinical changes in perfusion occur in abdominal and leg circulation, these changes are not consistent across vessels and regional tissue oxygenation remains unaffected.

Pulsed Doppler Echocardiography: An Historical Perspective

Over the past six decades, echocardiography has evolved into an important technique for not only imaging cardiac structures, but also, by employing the Doppler equation, for assessing cardiac blood flow and tissue velocities. This review focuses on pulsed Doppler echocardiography: its principles, early development, and clinical applications. Important clinical applications include: (1) measurement of flow velocities, stroke volumes, and regurgitant and shunt volumes; (2) assessment of time intervals, e.g., pulmonary artery acceleration time as a measure of pulmonary artery pressure and resistance or the timing of mitral regurgitation in hypertrophic cardiomyopathy; (3) detection of turbulent flow in regurgitation, stenoses, and shunts, enhanced by the implementation of color Doppler; and (4) evaluation of left ventricular diastolic function in conjunction with pulsed tissue Doppler and deformation (strain) measurements.

EP10.22: The reference values for pulsed wave Doppler measurements in fetal echocardiography for the Japanese population

EP10.22: The reference values for pulsed wave Doppler measurements in fetal echocardiography for the Japanese population

BALB/cJBom Treated with Angiotensin II and High Salt Diet Develop Pulmonary Hypertension and Right Sided Heart Failure while C57BL/6J Mice do not

Pulmonary arterial hypertension (PAH) is caused by increased pulmonary vascular resistance that can develop as part of other pathologies such as pulmonary embolism and heart failure, or because of pulmonary vascular remodeling. Right ventricle failure is the primary cause of death in patients with pulmonary hypertension. Interestingly, despite similar right ventricle systolic pressure and degree of hypertrophy, some patients rapidly develop right ventricle failure while others show prolonged periods of stability. Here we present a new mouse model of acute decompensated pulmonary hypertension displaying genetic predisposition to right‐sided heart failure.In a previous study we have seen that BALB/cJBom mice are more sensitive to a combination treatment of angiotensin II and high salt diet (AngII+Salt) compared to C57BL/6J. During the treatment BALB/cJBom mice develop massive edema and display very high mortality. The aim of present study was to elucidate the physiological and genetic mechanism responsible for the increased sensitivity in BALB/cJBom. BALB/cJBom and C57BL/6J mice were treated with AngII (0.5 μg/min/kg) and high salt diet (3%) and cardiac function was measured with echocardiography every day for seven days. BALB/cJBom treated with AngII+Salt display an increased pulmonary vascular resistance and right ventricle systolic pressure 24 hours following treatment initiation, assessed with Pulsed wave Doppler measurement of pulmonary artery flow. Increased pulmonary vascular resistance precedes diastolic dysfunction and reduced cardiac output, that is seen at day two and three respectively. Ejection fraction is not affected by AngII+Salt treatment. AngII+Salt does not affect cardiac function in C57BL/6J except increasing heart rate. This indicates a genetic susceptibility to pulmonary hypertension and right‐sided heart failure in BALB/cJBom. Linkage analysis identified a quantitative trait loci (QTL) at chromosome 3 which could explain the variation in change in cardiac output. Urine and sodium excretion, measured with metabolic cages when reduced cardiac output was established, was lower in BALB/cJBom mice treated with AngII+Salt than in C57BL/6J. Some BALB/cJBom mice did not excrete any urine during the 24‐hour measurement period, indicating acute kidney injury. QTLs on chromosome 2 and 3 were linked to changes in water and sodium regulation.In conclusion, BALB/cJBom treated with AngII+Salt develop decompensated pulmonary hypertension which is genetically predisposed. A QTL on chromosome 3 is linked to reduction in cardiac output during the setting of decompensated pulmonary hypertension. BALB/cJBom treated with AngII+Salt may work as an animal model to study the adaptive capacity of the right ventricle in pulmonary hypertension.Support or Funding InformationRegional Health Authority in Western NorwayÅke Wiberg foundationSwedish heart‐lung foundationSwedish Society of MedicineMarcus Borgström foundationSwedish Society for Medical ResearchThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Influence of perinatal low-dose acetylsalicylic acid therapy on fetal hemodynamics evaluated by determining the acceleration-time/ejection-time ratio in the ductus arteriosus.

Acceleration-time/ejection-time ratio (At/Et ratio) of Doppler waveform is an established hemodynamic parameters that reflect proximal stenosis. Using this parameter, we evaluated whether perinatal low-dose acetylsalicylic acid (ASA) therapy could alter hemodynamics in the ductus arteriosus. Pulse Doppler measurements of the fetal ductus arteriosus were performed longitudinally from 20 to 37 gestational weeks in 106 healthy pregnant women (controls) and 65 pregnant women taking daily low-dose ASA (80 or 100mg/day) because of a history of recurrent pregnancy loss. The At/Et ratio, pulsatility index (PI), and peak systolic velocity were evaluated and statistically analyzed. The At/Et ratio significantly increased with gestational age in both the ASA group (r=0.54) and the control group (r=0.35), while the PI did not. Median peak systolic velocities also increased with gestational age in both the ASA group (r=0.39) and the control group (r=0.31). No significant differences in At/Et ratio, PI, or peak systolic velocity were observed between the ASA group and the control group. Administration of low-dose ASA during pregnancy did not appear to alter hemodynamics in the fetal ductus arteriosus.

Reference intervals of echocardiographic measurements in healthy adult dairy goats.

ObjectivesTo determine references intervals for echocardiographic measurements in adult dairy goats.Animals125 clinically healthy, adult dairy goats aged 2–9 years, belonging to two breeds–Polish Fawn Improved (PFI, n = 64, weight range from 46 to 73, median of 58.5kg) and Polish White Improved (PWI, n = 61, weight range from 48 to 80 kg, median of 67.9kg), closely related to French Alpine and Saanen, respectively.MethodsNon-invasive transthoracic echocardiography examination was performed in unsedated goats in a standing position. Two-dimensional, M-mode and pulsed wave Doppler measurements were obtained. A non-parametric method was applied for determination of reference intervals. Measurements for the two breeds were compared using an analysis of covariance to control for their body weight. Repeatability was assessed using a between-day coefficient of variation and a coefficient of repeatability.ResultsFollowing reference intervals were determined: aortic diameter in diastole 2.2–3.3, left atrial diameter in systole 2.5–4.3cm cm, the ratio of the left atrial diameter to the aortic diameter 0.96–1.5, right ventricular internal diameter in diastole 0.4–1.7cm, left ventricular internal diameter in systole and diastole 1.8–3.2 and 3.2–5.6 cm, respectively, inter-ventricular septum thickness in systole and diastole 0.7–1.5 and 0.5–1.1cm, respectively, left ventricular posterior-wall in systole and diastole 0.8–1.6 and 0.5–1.2cm, respectively, E-point to septal separation 0.3–0.8cm, left ventricular fractional shortening 28–54%, left ventricular ejection fraction 55–86%, maximum Left and Right Ventricular Outflow Tract velocity 80–140 cm/s and 70–130 cm/s, respectively Left and Right Ventricular Outflow Tract pressure gradient 2.5–8.9mmHg and 1.9–6.5mmHg, respectively. Most of the differences between the two breeds could be attributed to different body weight.ConclusionsThe study provides echocardiographic reference intervals determined on the highest sample of apparently healthy goats so far enrolled.

Reported normal values and weighted means for commonly used echocardiography pulsed Doppler and tissue Doppler measurements.

Pulsed Doppler (PW) and tissue Doppler imaging (TDI) measurements are part of every echocardiography examination for evaluation of left ventricular (LV) diastolic function and filling pressure. The purpose of this study was to summarize published data on normal values for PW and TDI measurements. A PubMed search was performed on the 10th of October 2016 to identify relevant articles. Studies were considered relevant if they included more than 200 healthy individuals. A total of 13 studies were identified. Of these, 13 studies with 7777 subjects reported PW measurement over the mitral valve, six studies with 4082 subjects reported PW measurement in the pulmonary vein and 10 studies with 5988 subjects reported TDI. We also report weighted mean values for 14 different variables. As expected, measurements varied with age. There were no major differences between men and women. In contrast, there was a large difference in reported values between studies, in corresponding age groups. This review therefore raises caution about relying on normal values from just one study.

Corrected flow time: a noninvasive ultrasound measure to detect preload reduction by nitroglycerin

ObjectiveMonitoring of patient's intravascular volume status without invasive measures remains challenging and unreliable. Our objective was to determine if corrected flow time (FTc) measurement could detect preload reduction with administration of nitroglycerin (NTG) as a surrogate for volume loss. MethodsPost hoc FTc analysis was performed for a prospective cohort study of pulsed wave spectral Doppler measurements before and after administration of NTG. Patients enrolled were eligible for inclusion if they were admitted to a chest pain center for cardiac evaluation. Descriptive statistics, t tests, bivariate regression, and intraclass correlation coefficient were performed as appropriate. ResultsFifty-four patients had Doppler measurements available for review. Mean FTc decreased from 339 milliseconds (95% confidence interval, 332-346) to 325 milliseconds (95% confidence interval, 318-331) with administration of 0.3 mg of sublingual NTG (P=.0001). Mean heart rate increased 5 beats/min with administration of NTG (P<.0001); however, there was no significant change in systolic or diastolic blood pressure. ConclusionCorrected flow time was able to detect a significant difference in preload reduction with 0.3 mg of NTG. The FTc may be an early reliable noninvasive measure to detect changes in intravascular volume status.

Echocardiographic measurements of right heart size and function in healthy horses

Right ventricular (RV) function is scarcely described in horses. To establish reliable echocardiographic measurements of right heart size and function in horses. Descriptive study in healthy horses. Ten healthy untrained adult trotter horses underwent repeated echocardiography performed by 2 sonographers from right and left parasternal standard and nonstandard views. Nonstandard views included a right parasternal view focused on the right atrium, left parasternal long-axis pulmonary artery view, left parasternal long-axis view focused on the right ventricle including anatomical M-mode of tricuspid annular motion and left parasternal pulsed wave Doppler recording of pulmonary flow. During off-line analysis, 2 observers performed two-dimensional, M-mode, pulsed wave Doppler, tissue Doppler imaging (TDI) and two-dimensional speckle tracking (2DST) measurements of RV size and function. Acquisition and measurement variability were assessed by calculating coefficients of variation (CV) from one-way repeated measures analyses of variance. The degree of variability was classified as low (CV<15%), moderate (CV 15-25%) or high (CV>25%). Most two-dimensional and M-mode measurements of RV, right atrial and pulmonary artery size showed low variability. The two-dimensional, M-mode and pulsed wave Doppler measurements of RV function showed a low to moderate variability. Right ventricular functional measurements by 2DST showed low variability, except for segmental strain rate. Right ventricular functional measurements by TDI showed a low to high variability, with a lower variability for timing than for peak measurements and a lower variability for velocity compared with deformation measurements. Right heart size and function can be assessed with low variability in horses.

Assessing aortic regurgitation severity from 2D, M-mode and pulsed wave Doppler echocardiographic measurements in horses

Aortic regurgitation (AR) in horses can lead to left ventricular (LV) eccentric hypertrophy, ventricular arrhythmia and heart failure. Objective quantification of the severity of regurgitation is difficult. The aim of this study was to evaluate dimensional measurements, systolic time intervals and blood flow velocities, acquired by standard 2D, M-mode and pulsed wave Doppler echocardiography, for quantification of AR. Echocardiography was performed in 32 healthy horses and 35 horses with AR that were subdivided in three groups (mild, moderate or severe AR). From the recorded images LV, left atrial and aortic dimensions, systolic time intervals and aortic blood flow velocities were measured. Diastolic run-off in the aorta (AoDiastDecr) was calculated as the difference in aortic diameter between early diastole and late diastole. Stroke volume (SV) was calculated from pulsed wave Doppler measurements, by the bullet method (SVbullet) and by the area-length method. Pre-ejection period (PEP) and ejection time (LVET) were determined from the M-mode images.Horses with AR showed enlargement of the LV, left atrium and aorta compared to the control group. The SV, the AoDiastDecr and the rate of AoDiastDecr were significantly larger than controls. PEP decreased significantly in horses with AR, whereas LVET did not change. PEP and the newly defined variable AoDiastDecr proved to be easy to measure parameters that provided a good indication of AR severity. There was increased SV in horses with AR using all three methods, but SVbullet was superior for the detection of increased AR severity.

Mesenteric blood flow during vasovagal syncope

s selected for presentation 3.6 Mesenteric blood flow during vasovagal syncope D. Jardine, R. Pointon, I. Wright, T. Buckenham Department of General Medicine, Christchurch Hospital, New Zealand Department of Nuclear Physics, Christchurch Hospital, New Zealand Department of Radiology, Christchurch Hospital, New Zealand Rapid vasoconstriction of the splanchnic arterioles, controlled by the sympathetic nervous system is thought to be the most important mechanism for maintaining blood pressure during posture change, exercise and haemorrhage. It has been hypothesised that during vasovagal reactions, the baroreflexes transiently fail, allowing blood to pool in the splanchnic vessels. This results in decreased venous return and a steady fall in stroke volume output during the minutes preceding syncope.We aimed tomeasure mesenteric artery blood flow during tiltinduced syncope to see if “active” vasoconstriction was maintained as blood pressure fell.We selected 40 patients with a history of fainting and during 70-degree head-up tilt, we continuously monitored blood pressure [MAP] [Finapress], heart rate [HR] and muscle sympathetic nerve activity [MSNA]. We also did pulsed-doppler measurements from the superior mesenteric artery each minute. Using the pixel-averaging techniquewe quantified the area under thewave signal representative of diastolic flow and normalised this for systolic flow [NDF]. Patients were tilted for 30 minutes [GTN given at 20 minutes] or until presyncope. 18 patients [age 41 ± 15 yrs, 9 females] had tilt-induced presyncope after 21 ± 8minutes. During the last 5 minutes of tilt: BP fell from 98± 12mmHg to 70 ± 18 [p= 0.001]; HR from 82± 12 bpm to 74± 18 [p= 0.09]; MSNA from 47 ± 9 bursts/min to 37 ± 13 [p= 0.04] and NDF from 0.92 units to 0.75 [p= 0.02]. Despite a fall in MSNA during presyncope, active vasoconstriction is maintained in the splanchnic arterioles resulting in decreased diastolic blood flow. Stroke volume falls at this time, therefore a relative increase in systolic flow is not contributing to the fall in NDF. The dominant hypotensive mechanism in vasovagal syncope is likely to be splanchnic venous pooling which occurs despite decreased arterial inflow. doi:10.1016/j.autneu.2015.07.264 Symposium 4: Is renal nerve ablation a sound therapeutic strategy for the clinical treatment of hypertension? Insights gleaned from recent studies 4.1 Role of afferent and efferent renal nerves inmediating cardiovascular responses to renal denervation in experimental hypertension

Impaired exercise capacity and left ventricular function in long-term adult survivors of childhood acute lymphoblastic leukemia.

Survivors of childhood acute lymphoblastic leukemia (ALL) are at risk for late cardiotoxic effects of cancer treatment, but conflicting evidence exists on the effects of anthracyclines on left ventricular (LV) diastolic function and exercise capacity. We performed a cross-sectional study with comprehensive echocardiography in 138 adult survivors of childhood ALL, median 23.4 years after diagnosis. Pulsed tissue Doppler measurements of early diastolic mitral annular velocities (e') were used for the assessment of diastolic function, and compared to 138 matched controls. Of the survivors, 133 also performed ergospirometry measuring peak oxygen uptake (VO2 max). Associations between cancer treatment, LV function, and VO2 max were analyzed. The survivor group had lower e' values than controls (e' septal 11.0 vs. 12.6 cm/s, P < 0.001), but the difference was confined to the subgroup of anthracycline treated survivors (median cumulative dose 120 mg/m(2) ). Anthracycline exposure was inversely correlated with e' (regression coefficient -1.581, P=0.009). Reduced VO2 max/kg occurred in 47% of the survivors, but more often in anthracycline treated survivors (56%) than anthracycline naïve survivors (17%, P<0.001). Anthracycline exposure was inversely correlated with VO2 max/kg (regression coefficient -3.084, P = 0.05 in multivariate analysis). Furthermore, associations were observed between measures of LV function and VO2 max/kg, and e' was the best predictor of VO2 max/kg (standardized coefficient 0.355, P < 0.001 in multivariate analysis). Adult survivors of childhood ALL have increased risk for impaired LV diastolic function and impaired exercise capacity, both associated with previous anthracycline exposure. Furthermore, there is an association between LV diastolic function and exercise capacity.

Impaired right ventricular hemodynamics indicate preclinical pulmonary hypertension in patients with metabolic syndrome.

BackgroundMetabolic disease can lead to intrinsic pulmonary hypertension in experimental models. The contributions of metabolic syndrome (MetS) and obesity to pulmonary hypertension and right ventricular dysfunction in humans remain unclear. We investigated the association of MetS and obesity with right ventricular structure and function in patients without cardiovascular disease.Methods and ResultsA total of 156 patients with MetS (mean age 44 years, 71% women, mean body mass index 40 kg/m2), 45 similarly obese persons without MetS, and 45 nonobese controls underwent echocardiography, including pulsed wave Doppler measurement of pulmonary artery acceleration time (PAAT) and ejection time. Pulmonary artery systolic pressure was estimated from PAAT using validated equations. MetS was associated with lower tricuspid valve e′ (right ventricular diastolic function parameter), shorter PAAT, shorter ejection time, and larger pulmonary artery diameter compared with controls (P<0.05 for all). Estimated pulmonary artery systolic pressure based on PAAT was 42±12 mm Hg in participants with MetS compared with 32±9 and 32±10 mm Hg in obese and nonobese controls (P for ANOVA <0.0001). After adjustment for age, sex, hypertension, diabetes, body mass index, and triglycerides, MetS remained associated with a 20‐ms–shorter PAAT (β=−20.4, SE=6.5, P=0.002 versus obese). This association persisted after accounting for left ventricular structure and function and after exclusion of participants with obstructive sleep apnea.ConclusionsMetS is associated with abnormal right ventricular and pulmonary artery hemodynamics, as shown by shorter PAAT and subclinical right ventricular diastolic dysfunction. Estimated pulmonary artery systolic pressures are higher in MetS and preclinical metabolic heart disease and raise the possibility that pulmonary hypertension contributes to the pathophysiology of metabolic heart disease.

Uterine and arcuate arteries blood flow for predicting of ongoing pregnancy in in vitro fertilization.

Background:In this study, we aimed to investigate the ability of transvaginal Doppler ultrasonography in predicting in vitro fertilization (IVF) outcome in women undergoing this procedure.Materials and Methods:In this prospective observational study, 65 infertile women underwent IVF procedure in Isfahan, during 2013-2014, were studied. The pulsatility index (PI), resistive index (RI) and peak systolic velocity (PSV) of the uterine arteries and arcuate arteries were measured in all selected women using transvaginal color and pulsed Doppler measurements on the day of human chorionic gonadotrophin injection. The women followed up for the primary endpoint which was a successful pregnancy. The mean of PI, RI, and PSV were compared in groups of women who had successful IVF and not. The receiver operating characteristic (ROC) curve was used to determine the predictive value of studied indices.Results:In this study, from 65 women, 32 (49.2%) and 33 (50.8%) have successful and unsuccessful IVF outcome, respectively. The mean of PI and RI of both uterine and arcuate arteries were significantly lower in pregnant women than non-pregnant ones (P < 0.001). The area under the ROC curve of PI (84.7%) and RI (84.4%) for uterine arteries was higher than other indices. The most accurate indices for predicting the outcome of IVF was RI of uterine arteries with an accuracy of 81.5%.Conclusion:The findings of this study indicated that PI and RI assessments of uterine arteries could be used as a routine non-invasive factor, before hCG stimulation, for predicting the outcome of IVF.

SAT0190 A Diagnostic Protocol for GIANT Cell Arteritis (GCA) Using Ultrasound Assessment

BackgroundUltrasound (US) has been used in the diagnosis of GCA since the early 90's, however it has not yet superseded temporal artery biopsy as a diagnostic test, either in practice...