Pulsed-wave Doppler Research Articles

Abstract 17496: Exploring the Benefits: Role of Repeat Transesophageal Echocardiography (TEE) in Patients Anticoagulated for Four Weeks

Background: A left atrial appendage (LAA) thrombus is a well-known complication of atrial fibrillation (AF). Vitamin K antagonists (VKAs) have been well studied been considered the gold standard for thromboembolic prophylaxis. We present a case of LAA thrombus despite compliance with VKAs. Clinical presentation: A 70-year-old female with atrial fibrillation and diabetes presented with left-sided weakness and left facial droop, CT head showed right middle cerebral artery infarct. Vitals were unremarkable. Electrocardiogram showed AF with a rapid ventricular response. She was on warfarin with the most recent international normalized ratio level of 2.3. Transthoracic echocardiography revealed an ejection fraction of 55%, severe left ventricular hypertrophy, and severely dilated left atrium (LA) with LA diameter of 5.3 cm (>= 4.7 cm in women indicates severe dilatation). Transesophageal echocardiography (TEE) with bubble study demonstrated a large thrombus in the LAA with evidence of patent foramen ovale. The pulse wave Doppler (PWD) of the LAA on TEE also showed an LAA velocity of <20 cm/sec, which indicated that there was the highest probability that the thrombus was forming within LAA. Hypercoagulability work-up for thrombosis while on Coumadin such as anti-B2 glycoprotein, anticardiolipin, and factor V Leiden mutation were negative. The patient was started on enoxaparin with appropriate follow-up upon discharge. Discussion: The prevalence of LAA thrombus in patients with AF receiving a minimum of 3 weeks of anticoagulation, was approximately 3%. The presence of a LAA thrombus is a known contraindication to cardioversion and catheter ablation in patients with AF as it can result in cardioembolic stroke. However, current guidelines for cardioversion do not recommend pre-procedural TEE in patients undergoing cardioversion for AF if they have been on therapeutic oral anticoagulation for at least 3 weeks while TEE use remains variable before catheter ablation.

Abstract 14039: Therapeutic Potential of Beta Hydroxybutyrate in Nonalcoholic Fatty Liver Disease (NAFLD)-Induced Cardiovascular Disease

Background: Cardiovascular disease (CVD) is the leading cause of mortality in non-alcoholic fatty liver disease (NAFLD). Beta hydroxybutyrate (BHOB), a liver metabolite, is the major ketone that serves as an alternative fuel source in the body. Our previous studies show that hepatocyte peroxisome proliferator activator receptor-α knockout (Ppara HEPKO ) mice, model of NAFLD-induced CVD, exhibit reduced circulating levels of BHOB. Hypothesis: We hypothesized that restoring plasma BHOB levels will improve cardiovascular function in Ppara HEPKO mice. Aims: To determine the therapeutic role of BHOB in NAFLD-induced CVD. Methods: 30 weeks old male Ppara HEPKO mice were given 1,3 butanediol (20% in drinking water) (Ppara HEPKO + BHOB) or vehicle (Ppara HEPKO ) (n=6) for 6 weeks. Plasma BHOB was measured at baseline and after treatment. Cardiac structure and function were measured by high resolution ultrasound echocardiography (VEVO 3100), using the B-mode, M-mode, pulse wave and tissue doppler at baseline and after treatment. Mean arterial blood pressure was measured by radiotelemetry. Liver fat was determined by EchoMRI, Oil Red O staining and hepatic triglyceride levels. Results: After 6 weeks of BHOB treatment, Ppara HEPKO exhibit increased plasma BHOB compared to baseline (0.5 ± 0.01 vs. 0.2 ± 0.02mmol/L), attenuated arterial blood pressure compared to control (109 ± 3 vs. 121 ± 4mmHg), improved systolic function: cardiac output (13.8 ± 0.8 vs. 11.1 ± 0.7ml/min), stroke volume (31.1 ± 2.1 vs. 23.4 ± 1.3ml/min), improved diastolic function: isovolumic relaxation time (18.7 ± 0.8 vs. 20.6 ± 0.9m/sec), E/e’ (-29.6 ± 0.9 vs. -32.4 ± 1.4), and attenuated vascular stiffness. Interestingly, BHOB did not alleviate hepatic fat compared to control as demonstrated by EchoMRI (0.8 ± 0.3 vs. 0.7 ± 0.3), hepatic triglyceride (1.4 ± 0.3 vs. 1.3 ± 0.2mM) and Oil Red O staining. Conclusion: Our findings indicate that BHOB treatment improves arterial blood pressure, systolic, diastolic, and vascular function in, Ppara HEPKO knockout mice. However, BHOB did not alleviate hepatic steatosis suggesting that BHOB improves cardiovascular function in Ppara HEPKO mice independent of changes in hepatic fat content.

Abstract 14030: Hemodynamic Metrics Can Be Accurately Assessed by a Non-Invasive Sensor Patch: The Portable Technology for Wireless Cardiomyopathy Tracking (Patchwrk) Study

Background: Echocardiographic timing intervals provide valuable prognostic information in patients with pre-clinical cardiac dysfunction. Diastolic filling time (DFT) can identify left bundle branch block (LBBB) patients at higher risk for cardiomyopathy. The need for specialized equipment limits the utility of echo in longitudinal assessment. Hypothesis: A non-invasive multimodal sensor Sansa patch will enable accurate assessment of hemodynamic parameters such as DFT, ejection time (ET), and pre-ejection period (PEP). Methods: Fifty patients scheduled for clinically indicated echocardiography were prospectively enrolled and had simultaneous application of the Sansa patch at the time of echocardiography. Timing intervals were analyzed using continuous wave (CW), pulsed wave (PW), and tissue Doppler imaging (TDI). Data from the Sansa electrocardiogram (ECG), seismocardiogram (SCG), and phonocardiogram (PCG) were independently analyzed to identify valve openings/closures to estimate DFT, ET and PEP. Agreement between echo and Sansa estimates was assessed using the coefficient of determination (R 2 ) and compared with agreement between different echo views. Results: Forty-six of the 50 patients (92%) had data of sufficient quality for analysis. The mean ejection fraction was 53±8% and 11 patients (24%) had LBBB. By echo, the mean DFT, ET, and PEP were 408±137 milliseconds (ms), 297±35ms, and 107±32ms respectively. Sansa estimates for DFT, ET and PEP were 431±135ms, 286±43ms, and 89±34ms respectively. The R 2 for Sansa DFT compared to echo was 0.85. Comparing TDI and PW estimates of DFT within the same patients demonstrated an R 2 of 0.82. Conclusion: Non-invasive Sansa patch monitoring accurately identified key cardiac timing intervals within the error observed between standard echo views. These measures have prognostic value and monitoring them in the ambulatory setting may allow early cardiomyopathy detection and upstream intervention.

Abstract 13419: Transient Coronary Artery to Left Ventricular Fistula With Diastolic Mitral Regurgitation

Introduction: A fistula from a coronary artery to the cardiac chamber is incidentally found in 0.08% to 0.3% of patients undergoing coronary angiography. Case Presentation: A 73-year-old woman with hypertension, diabetes mellitus, chronic renal failure, and nephrosis visited our department due to dyspnea. The patient’s physical examination revealed a blood pressure of 191/109 mmHg and a pulse rate of 77 beats per min. The blood sampling results revealed a plasma brain natriuretic peptide level of 2,001 pg/mL. A 12-lead electrocardiogram showed poor R wave progression in leads V1 to V4. Chest radiography revealed left pleural effusion. Parasternal transthoracic echocardiography showed left ventricular hypertrophy. Left ventricular (LV) ejection fraction was 41%. A pulsed-wave Doppler echocardiography at the mitral inflow showed diastolic mitral regurgitation and a fusion of E and A waves. An unusual myocardial flow was noted in the apical myocardium. It was directed toward the apical surface during systole (Fig. 1a), and directed toward the LV lumen during diastole (Fig. 1b), suggesting coronary artery to LV fistula through sinusoid. Global strain obtained from apical long axis imaging showed myocardial shortening continued to diastole, suggesting post-systolic shortening (PSS). After treatment for hypertension, both of myocardial flow and diastolic MR disappeared. A longitudinal global strain imaging revealed disappearance of PSS. Conclusion: This is a rare case of diastolic MR due to PSS at the fistula from the coronary artery to the left ventricle.

Case Series: Multiple Soft Tissue Lesions Demonstrated by Sonography and MRI Correlation

Varied diagnostic imaging techniques may often be used in tandem, to enhance and complement each other, when an initial imaging diagnosis appears equivocal. Diagnostic medical sonography and magnetic resonance imaging (MRI) are imaging techniques that often complement each another. Sonography is an excellent diagnostic technique to determine the consistency of a soft tissue mass (e.g., solid vs cystic), and its relationship to adjacent structures, size, and shape. Sonography is especially useful for evaluating palpable lumps and allows sonographers to perform targeted examinations around the area of interest. In addition, color and pulsed-wave Doppler enable further characterization of a lesion’s presence or lack of vascularity. Sonography can also guide core-needle biopsy of superficial lesions. However, sonography is less reliable for deep masses in large anatomical regions. The American College of Radiology recommends MRI for deeper lesions of this type. Magnetic resonance imaging is also recommended for soft tissue masses suspected to be localized to the peripheral nervous system.

Variability in Interpretation of Echocardiographic Signs of Tamponade: A Survey of Emergency Physician Sonographers

BackgroundCardiac tamponade is associated with high mortality, and making the diagnosis is a core skill of emergency physicians. Proper diagnosis relies on specific clinical and echocardiographic findings. It is not known whether expert sonographers consistently recognize echocardiographic signs of tamponade. ObjectivesTo assess whether expert sonographers agree on echocardiographic signs of tamponade. MethodsA 20-question survey consisting of 18 cine loops and 2 still images was distributed to the Academy of Emergency Ultrasound Section of the Society for Academic Emergency Medicine. Respondents answered “yes” or “no” to whether there was echocardiographic evidence of tamponade. Subgroup analyses of demographics and echocardiographic views were reported. The data were analyzed using Krippendorff's alpha (α) to assess interrater reliability (IRR) between respondents. ResultsEighty-four physicians responded and 56 completed the survey. All partial and completed surveys were analyzed. The overall IRR was poor (α = 0.60, 95% confidence interval [CI] 0.44–0.76). Residency graduation within 5 years (α = 0.66, 95% CI 0.5–0.8) was associated with higher IRR compared with those > 5 years (α = 0.53, 95% CI 0.37–0.69). The highest IRR was observed when images of mitral valve inflow pulse-wave Doppler (α = 0.81, CI 0.70–0.92) were used and the poorest IRR was on images from the parasternal short view (α = 0.28, 95% CI 0.05–0.49). ConclusionThere was poor agreement among expert emergency medicine sonographers in identifying echocardiographic signs of cardiac tamponade from a single cine loop or clip without clinical context. Further investigation is warranted to understand differences in recognition of clinical tamponade.

Clinical features, etiology, and survival in patients with restrictive cardiomyopathy: A single-center experience.

Numerous prognostic factors have been proposed for cardiac amyloidosis (CA). The knowledge about other subtypes of restrictive cardiomyopathy (RCM) is scant. This study aimed to elucidate the etiology and prognostic factors of RCM as well as assess cardiac biomarkers: high-sensitive troponin T (hs-TnT), growth differentiation factor-15 (GDF-15), N-terminal pro-B-type natriuretic peptide (NT-proBNP), and soluble suppression of tumorigenicity 2, as mortality predictors in RCM. We enrolled 36 RCM patients in our tertiary cardiac department. All patients were screened for CA. Genetic testing was performed in 17 patients without CA. Pathogenic or likely pathogenic gene variants were found in 86% of patients, including 5 novel variants. Twenty patients died, and 4 had a heart transplantation during the study. Median overall survival was 29 months (8-55). The univariate Cox models analysis indicated that systolic and diastolic blood pressure, GDF-15, hs-TnT, NT-proBNP, left ventricular stroke volume, the ratio of the transmitral early peak velocity (E) estimated by pulsed wave Doppler over the early mitral annulus velocity (e'), tricuspid annulus plane systolic excursion, early tricuspid valve annular systolic velocity, the presence of pulmonary hypertension, and pericardial effusion influenced survival (P <0.05). A worse prognosis was observed in patients with GDF-15 >1316 pg/ml, hs-TnT >42 ng/l, NT-proBNP >3383 pg/ml, and pericardial effusion >3.5 mm (Kaplan-Meier analysis, log-rank test, P <0.001). Genetic testing should be considered in every RCM patient where light-chain amyloidosis has been excluded. Survival remains poor regardless of etiology. Increased concentrations of GDF-15, hs-TNT, NT-proBNP, and pericardial effusion are associated with worse prognosis. Further studies are warranted.

First experiences of ultrasound vector flow imaging at the femoropopliteal artery in peripheral arterial disease.

Background: The femoropopliteal artery (FPA) plays a central role in diagnosing and treating peripheral arterial disease (PAD). FPA lesions are the most frequent cause of intermittent claudication, and no other artery of the lower extremities is recanalised more frequently. Generally, ultrasound is the primary imaging tool in PAD, particularly FPA. With the development of high-frame-rate ultrasound technology in addition to traditional ultrasound modes, vector flow imaging (VFI) has provided deeper haemodynamic insights when used in the carotid artery. Here, we report the use of VFI at the FPA level in routine PAD examinations. Patients and methods: In this single-centre prospective study, we evaluated consecutive patients with PAD using B-mode imaging, colour Doppler, pulsed wave Doppler (PW) and vector flow. Hemodynamic parameters at predefined locations at the carotid artery and FPA were compared. Results: Qualitatively adequate VFI at all sites was possible in 76% of the patients with PAD. With decreasing volume flow from the common carotid artery to the internal carotid artery and from the common femoral artery via the superficial femoral artery to the popliteal artery, the correlation between VFI- and PW-derived-volume flow was high at every site. Based on different techniques, the VFI-derived values were significantly lower than the PW-derived values. The mean wall shear stress was significantly lower at all femoropopliteal sites than at the carotid sites, whereas the oscillatory shear index at the femoral site was higher than that at the carotid sites rather than at the popliteal location. Conclusions: Our findings suggest that vector flow data acquisition in the FPA is feasible in most patients with PAD. Therefore, with knowledge of the method and its limitations, VFI provides haemodynamic information beyond traditional ultrasound techniques and is a promising new tool for flow analysis in PAD.

Pulsed wave Doppler ultrasound: Accuracy, variability, and impact of acquisition parameters on flow measurements.

Pulsed wave Doppler ultrasound is a useful modality for assessing vascular health as it quantifies blood flow characteristics. To facilitate accurate diagnosis, accuracy and consistency of this modality should be assessed through Doppler quality assurance (QA). The purpose of this study was to characterize the accuracy, reproducibility, and inter-scanner variability of ultrasound flow velocity measurements via a flow phantom, with a focus on the effect of systematic acquisition parameters on measured flow velocity accuracy. Using a manufacturer-calibrated flow phantom, pulsed wave measurements were acquired on five clinical systems (iU22, Philips) with three models of transducers, including both linear and curvilinear models. The peak and mean flow velocities were estimated by vendor-supplied spectral analysis tools. To investigate intra- and inter-scanner variability, measurements were repeated using each scanner-transducer pair under a standardized set of conditions. Inter-scanner variability was assessed using ANOVA. Flow velocity accuracy was investigated by mean absolute percentage error. The impacts of receive gain, measurement depth, and beam steering on measured flow velocity accuracy were examined by varying each parameter over its available range and comparing to the ground truth flow velocity. Inter-scanner variability was statistically significant for peak flow measurements made using both linear and curvilinear transducers, though absolute differences in measured velocity were small. Inter-scanner variability was not statistically significant for mean flow velocity. Receive gain, measurement depth, and beam steering were all found to impact the accuracy of measured flow characteristics for linear transducers. Accuracy of the flow measurements made with the curvilinear transducer demonstrated high consistency to changes in receive gain at a constant depth, though were impacted by increasing the measurement depth. Carefully and consistently selected acquisition and set-up parameters are essential in order to establish a reliable and meaningful QA program.

Standardized Methodology for Duplex Ultrasound Examination of Arteriovenous Access for Hemodialysis: A Proposal of the French Society of Vascular Medicine and the French-Speaking Society of Vascular Access.

Duplex ultrasound (DUS) is an essential tool for characterizing and monitoring arteriovenous (AV) access for hemodialysis. The aim of the work described here, requested by the French Society of Vascular Medicine in collaboration with the French-Speaking Vascular Access Society, is to propose a standardized methodology for performing and documenting DUS, taking into account the variety of AV access techniques and the problems routinely encountered. A steering committee reviewed the literature and selected the relevant references. A draft was prepared, and all items with missing or conflicting data were submitted to a Delphi consensus. The final document was discussed and approved by all participants. The principles of DUS evaluation of AV access consist of examination of the afferent artery, the anastomosis and the entire venous drainage system. DUS uses B-mode ultrasound, color flow, pulsed wave and power Doppler analysis. DUS can be used in a variety of clinical situations, which can directly influence the methodology of the examination and the interpretation of the results. Blood flow should be assessed as it correlates with the risk of thrombosis. The measurement should be adapted to the different anatomical and hemodynamic conditions encountered. Characterization of stenosis should take into account the residual diameter of the drainage vein and its hemodynamic consequences. Other complications can be assessed with a standardized DUS examination. When performed according to a rigorous methodology, DUS of the AV access allows a comprehensive assessment of its functionality and eliminates the need for further invasive diagnostic procedures.

Doppler parameters in ductus venosus during the third trimester of pregnancy in goats.

The aim of the study was to assess hemodynamics in ductus venosus in the third trimester of pregnancy. Measurements of blood flow parameters in ductus venosus were performed using color Doppler combined with the pulsed-wave Doppler technique. In the analyzed period, the wave spectrum of blood flow in the ductus venosus had a specific pulsating character with two acceleration phases visible. The presented study showed an increase in peak systolic velocity, end-diastolic velocity, resistance index and pulsatility index in the last period of the third trimester of pregnancy. All Doppler parameters in the ductus venosus were correlated with the day of gestation. It has been shown that blood flow parameters and the Doppler spectrum depend on the gestational age. The obtained results may be useful for the future study of ductus venosus in fetal period in goats.

Reliable measurement methods for the isovolumic relaxation time: comparisons of dual gate Doppler and seven other methods

PurposeIsovolumic relaxation time (IVRT) is a useful indicator of diastolic dysfunction. However, a measurement method for IVRT has not been established. The Dual Gate Doppler method, which can record two separate pulse-wave Doppler signals simultaneously using two sample gates, may be ideal for measuring IVRT. This study aimed to evaluate the accuracy of IVRT measured using conventional methods versus that measured using the Dual Gate Doppler method.MethodsA total of 104 patients (mean age 58 ± 21 years, 48 women) were examined using ultrasound equipment with Dual Gate Doppler at our hospital. In addition to Dual Gate Doppler method, IVRTs were measured using seven different methods: pulsed Doppler (PW method), continuous wave Doppler (CW method), and other methods. The IVRT values obtained using the Dual Gate Doppler method were compared with those measured using other methods.ResultsAll IVRTs measured using conventional methods showed a strong correlation with the that measured using the Dual Gate Doppler method. However, there were slight deifferences among the IVRTs depending on the method. The PW method and the PW time difference method using only the PW showed small statistical bias and were not complicated. The IVRT measured using the CW method was significantly longer than that measured using the Dual Gate Doppler method.ConclusionsAmong the conventional methods, the PW method was the simplest and most practical method for measuring the IVRT in any conditions as arrhythmias. It is important to recognize the characteristics of IVRTs based on the measurement method.

Mitral annular disjunction and Pickelhaube sign in children with mitral valve prolapse: A prospective cohort study

BackgroundMitral annular disjunction (MAD) and the Pickelhaube sign are identified as risk factors for malignant ventricular arrhythmias (VAs) and sudden cardiac death in adults with mitral valve prolapse (MVP); their prevalence and consequences in children have never been studied. ObjectivesTo determine the proportion of MAD in children with MVP, and its potential link with VAs. MethodsA cohort of 49 consecutive children (mean age 12.8±3.0 years; 33 females) with MVP and comprehensive clinical arrhythmia (24-hour monitoring) and Doppler echocardiographic characterization, including pulsed-wave tissue Doppler (PWTD) of the lateral mitral annulus, was identified. The relationship between clinical and echocardiographic data and presence of VAs was studied. ResultsMAD was common (n=25; 51%). Only five patients had significant VAs (Lown grade>2) characterized by polymorphic premature ventricular contractions or couplets. MAD was not associated with VAs on 24-hour Holter monitoring, but an association was found between VAs and spiked high-velocity midsystolic signal>16cm/s on PWTD (Pickelhaube sign) (P=0.004), myxomatous mitral valve (P=0.004) and left ventricular dilatation (P=0.01). T-wave inversion in inferolateral leads on electrocardiogram was more frequent in patients with versus without the Pickelhaube sign (P=0.03). No difference was found between patients with or without MAD regarding sex, history of palpitation, severity of mitral regurgitation, aortic root diameter and incidence of connective tissue disorders. Myocardial fibrosis was detected in two of three patients who underwent a complementary cardiac magnetic resonance examination. ConclusionsMAD is common in children with MVP; its presence was not associated with significant VAs on 24-hour Holter monitoring, but the Pickelhaube sign and presence of myxomatous mitral valve may help to detect patients prone to significant VAs. Myocardial fibrosis can be detected by cardiac magnetic resonance in children with significant VAs.

Diagnostic value of pulsed wave doppler in pneumothorax: a prospective study.

The diagnosis of pneumothorax is usually made through clinical examination and radiography. Pulsed wave (PW) Doppler mode has not previously been used in the diagnosis of pneumothorax on chest USG. The aim of this study is to present, for the first time, a new finding demonstrating pleural movements using PW Doppler mode and to examine the value of the new sonographic finding in the diagnosis of pneumothorax. We investigated the presence of PW artifact in patients with and without pneumothorax using the high-frequency probe in PW Doppler. The Dogan's sign, defined as the absence of PW artifact, was then compared with lung sliding and the barcode sign in pulsed wave Doppler for the diagnosis of pneumothorax. Of the 141 patients, 39 were in the pneumothorax group. The sensitivity and specificity of the Dogan's sign in the diagnosis of pneumothorax were 95.12% and 99.3%, respectively, in this study. The sensitivity and specificity of lungsliding were 95.12% and 98.08%, respectively; the sensitivity and specificity of the barcode sign were 92.86% and 98.08%, respectively, in the diagnosis of pneumothorax by ultrasonography in this study. PWDoppler is a useful tool in the diagnosis of pneumothorax. It has a high sensitivity and specificity for the detection of pneumothorax. It is also superior to both lung sliding and the barcode sign in detecting pneumothorax. The Dogan's sign can be used safely in the diagnosis of pneumothorax, together with lung sliding and the barcode sign.

Yeo's index: A novel index that combines anatomic and haemodynamic assessment of the severity of mitral stenosis

BackgroundA mitral leaflet separation index (MLSI), measuring the anatomical separation of the mitral valve (MV) leaflet tips in diastole, was previously described as an accurate method of assessing mitral stenosis (MS). We propose a novel modification of the MLSI by including a hemodynamic assessment which we term Yeo's index that may improve its diagnostic performance. Methods and resultsWe retrospectively studied 174 patients with varying severity of MS without significant mitral regurgitation, aortic valve disease or ventricular septal defect. MLSI was measured in 2 orthogonal views on transthoracic echocardiography as previously described. MV dimensionless index (DI) was calculated by dividing the left ventricular outflow tract pulsed-wave Doppler time velocity integral (TVI) by the MV continuous-wave Doppler TVI. We defined Yeo's index as the product of MLSI and DI. With linear correlation, Yeo's index demonstrated good correlation against MVA by planimetry (r = 0.728), pressure half-time (r = 0.677), and continuity equation (r = 0.829), with improved performance over the MLSI. Using ROC analysis, Yeo's index demonstrated good ability to correctly classify MS as severe (MVA ≤1.5cm2) (AUC 0.874, 95% CI 0.816–0.920). Yeo's index ≤0.260 cm correctly classified severe MS with sensitivity of 82% and specificity of 80%. Presence of AF did not affect the performance of Yeo's index. Yeo's index ≤0.147 cm also identified very severe MS (MVA ≤ 1.0 cm2) with specificity of 94% and sensitivity of 78%. ConclusionYeo's index performed well in identifying severe MS and may be a useful adjunct to existing measures of MS severity.

Effects of prenatal Doppler ultrasound on the retina of the chick embryo in ovo.

Currently, the effect of prenatal ultrasound on foetal development is intensively discussed and the guidelines for prenatal diagnostics have been changed. However, data supporting these concerns are scarce. Therefore, we used an established in ovo model of the chicken embryo to investigate cell proliferation and apoptosis within the retina. A total of 21 chicken eggs were fenestrated on Day 5 and allocated to either the control (n = 8) or exposition group (n = 13). The exposition group was treated with pulsed-wave Doppler ultrasound (PWD) for 10 min while controls remained without treatment. After subsequent incubation (6-48 h), the eggs were sacrificed, and chicken embryos were examined morphologically (HE-staining) and immunohistochemically. Counting of apoptotic and proliferating cells per retina was performed using antibodies specific for phospho-histone-H3 and active caspase-3 in combination with a biotin-labelled secondary antibody and peroxidase conjugated avidin-biotin complex for chromogenic detection. Due to a rather low number of specimens at each time point after ultrasound exposition, we neglected the effects of incubation time and focused on treatment effects. This approach revealed that the median number of proliferating cells is reduced after 10 min of exposure to PWD (569 vs. 766), while the number of apoptotic cells is fairly comparable between groups (5 vs. 6). Our data contribute to a better understanding of prenatal US on foetal development by suggesting that PWD could have an impact on the number of proliferating cells in the developing chicken retina and therefore justify further investigations.

Doppler ultrasonography can be used to evaluate the arterial blood supply of hip joints in skeletally immature cats.

To investigate hemodynamics and morphology of hip joint vasculature in cats with the use of color and pulsed-wave Doppler ultrasonography. 30 client-owned healthy skeletally immature cats presented for routine examinations between September 7, 2022, and March 25, 2023. Cats between 3.5 to 18 months old with healthy hip joints and Hct within reference ranges (26% to 44.2%) were eligible for inclusion. Color and pulsed-wave Doppler ultrasonography was performed without sedation. Peak systolic velocity (PSV), mean diastolic velocity (MDV), resistance index (RI), and pulsatility index (PI) were measured for major arteries of the hip joints. Intermediate pulsatility, resistance to flow, and pandiastolic anterograde flow were evident for all arteries evaluated for each joint except for the ligamentum capitis ossis femoris artery (LCOFA). Spectral waveforms for the LCOFA showed a low-resistance pattern with continuous forward diastolic flow. No significant differences were found in the mean PI or MDV between the left and right sides for the ascending branch of the lateral circumflex femoral artery or in the mean PI of the ascending branch of the medial circumflex femoral artery. Mean PSV of the LCOFA was lower (but nonsignificantly) for left hip joints vs right hip joints, whereas other values were often higher on cats' left side vs their right. This study provided insight into the morphology and hemodynamics of the femoral head vasculature in skeletally immature cats and showed Doppler ultrasound values to study the clinically normal blood supply to hip joints in cats.

Normal physiologic coronary flow velocity gradient across the left anterior descending artery in healthy asymptomatic subjects

Aim: Coronary flow velocity (CFV) can be obtained with transthoracic echocardiography (TTE) in the left anterior descending coronary artery (LAD). The physiologic flow velocity gradient across the different segments of LAD has not been established. This study aims to assess the normal values of resting CFV in proximal, mid, and distal LAD. Methods: In a single center, prospective, observational study design, TTE was attempted on 110 consecutive, asymptomatic middle-aged subjects (age = 55 years, 46% males) with a low likelihood of coronary artery disease (&lt; 5%). Resting CFV in the LAD was assessed with high-end machines, dedicated coronary pre-set, and high-frequency transducers by pulsed-wave Doppler under color-Doppler guidance in the proximal, mid, and distal segments. Results: The technical success rate for CFV imaging was lowest for the proximal (101/110, 92%), intermediate for mid (106/110, 96%), and highest for the distal segment (108/110, 98%). All 3 segments were interpretable in 101 subjects. CFV was highest in proximal segments (38.6 cm/s ± 3.9 cm/s), intermediate in mid segments (34.3 cm/s ± 6.04 cm/s, P &lt; 0.01 vs. proximal), and lowest in distal segments (28.1 cm/s ± 1.7 cm/s, P &lt; 0.01 vs. proximal and vs. mid). Conclusions: A resting evaluation of CFV-LAD can be obtained by TTE in the large majority of consecutive subjects referred to the echocardiography laboratory. Feasibility is highest for distal and lowest for proximal-LAD segments. There is a clear physiologic gradient of CFV with decreasing values, of about 10% for each step, going from proximal to mid and distal segments of LAD. When resting CFV is considered, the site of the sampling is important to obtain comparable and physiologically meaningful data.

Impact of Asthma Phenotypes on Myocardial Performance and Pulmonary Hypertension in Children and Adolescents With Moderate to Severe Persistent Asthma.

Asthma is characterized by chronic inflammation and remodeling of pulmonary vessels and airway wall resulting in pulmonary hypertension (PH). Increased afterload on right ventricle (RV) myocardium leads to RV diastolic dysfunction (RVDD). Echocardiography is an excellent tool to detect these changes early. Using echocardiography, we assessed the impact of clinical asthma phenotypes on myocardial performance and PH in children with asthma. Sixty children with moderate or severe persistent asthma and 60 age and gender-matched healthy controls were enrolled. As per clinical phenotypes, children with asthma were classified into early wheezers (n = 30) and late wheezers (n = 30). Pulmonary function tests (PFT) and echocardiography, both conventional and pulse wave (PW), were performed. Children with asthma had significant RVDD and higher incidence (33%) of PH. Myocardial performance index (MPI) was poor in asthmatics, 0.41 (0.04) compared to controls, 0.38 (0.03). Measures for PH such as tricuspid regurgitation (TR) gradient, TR velocity, and pulmonary artery pressure (PAP) were significantly higher in cases. Among clinical asthma phenotypes, there was no difference in left ventricular ejection fraction (LVEF) between early 64.3% (4.6) and late wheezers 65.6% (4.4). MPI was better in late wheezers at 0.41 (0.05) than in early wheezers at 0.40 (0.03). TR gradient, TR velocity, and PAP were significantly higher in early wheezers. The odds ratio for the development of PH was 0.74 (CI 0.25 - 2.17), and for the development of RVDD was 3.2 (CI 0.77 - 13.8), both in favor of early wheezers. Children with asthma, particularly early-onset wheezers are at increased risk of developing PH and RVDD. We suggest annual screening by conventional echocardiography and pulse wave Doppler imaging for early diagnosis and timely initiation of management.

Dynamic Assessments of Coronary Flow Reserve after Myocardial Ischemia Reperfusion in Mice.

After cardiac ischemia, there is often insufficient myocardial perfusion, even if flow has been successfully and completely restored in an upstream artery. This phenomenon, known as the "no-reflow phenomenon," is attributed to coronary microvascular dysfunction and has been associated with poor clinical outcomes. In clinical practice, a reduction in coronary flow reserve (CFR) is frequently used as an indicator of coronary artery disease. CFR is defined as the ratio of the peak flow velocity induced by pharmacologic or metabolic factors to the resting flow velocity. This protocol focused on assessing the dynamic changes in CFR before and after ischemia-reperfusion (IR) using pulse wave Doppler measurements. In this study, normal mice exhibited the ability to increase the peak velocity of coronary blood flow up to two times higher than the resting values under isoflurane stimulation. However, after ischemia-reperfusion, the CFR at 1 h significantly decreased compared to the pre-operation baseline. Over time, the CFR showed gradual recovery, but it remained below the normal level. Despite the preservation of systolic function, early detection of microvascular dysfunction is crucial, and establishing a practical guide could aid doctors in this task, while also facilitating the study of cardiovascular disease progression over time.