pulsed wave Doppler ultrasound pulsed Doppler ultrasound [keywords]
- Corrected flow time: a noninvasive ultrasound measure to detect preload reduction by nitroglycerin. [JOURNAL ARTICLE]
- Am J Emerg Med 2016 Jun 24.
Monitoring 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.Post 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.Fifty-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.Corrected 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.
- B-Flow Imaging in Lower Limb Peripheral Arterial Disease and Bypass Graft Ultrasonography. [JOURNAL ARTICLE]
- Ultrasound Med Biol 2016 May 21.
Doppler ultrasonography plays a key role in the diagnosis of peripheral arterial disease, but is often limited by pitfalls that may be overcome by B-flow imaging. Thus far, there is little information on B-flow imaging for the assessment of peripheral arterial disease and bypass grafts in lower limbs. This article describes the authors' early experience with B-flow in the lower extremities. Sixty patients were included among a large cohort of patients routinely referred to the vascular laboratory for peripheral arterial disease and bypass graft assessments. Two experienced vascular sonographers performed all scans, comparing color Doppler ultrasonography with B-flow imaging. All scans were performed using a combination of the 9 L linear and C2-9 curvilinear transducers with the LOGIQ E9 system (GE Healthcare, Waukesha, WI, USA). Our experience indicates that this relatively unexplored technology has the potential to significantly improve peripheral blood flow evaluation. Nevertheless, B-flow imaging is not exempt from limitations and should be considered complementary to color Doppler ultrasonography.
- [Assessing resveratrol effect on ocular blood flow in experiment]. [English Abstract, Journal Article]
- Vestn Oftalmol 2016 Mar-Apr; 132(2):55-61.
To study the effect of resveratrol on ocular blood flow in vivo in healthy rats and those that underwent retinal ischemia/reperfusion.The experimental study was performed on 40 Wistar rats (40 eyes). For ocular blood flow evaluation, color Doppler imaging (CDI), power Doppler (PD), and pulsed-wave spectral Doppler ultrasonography were performed using the Voluson E8 Expert ultrasonic diagnostic system (GE Healthcare). All rats were given resveratrol per os for 2 months of the study. Retinal ischemia/reperfusion injury was induced by a subconjunctival injection of endothelin-1. The control group included 10 intact animals.Signs of ischemic damage of the anterior and posterior eye segments were less pronounced in rats that were given resveratrol during both pre-ischemic (30 days) and post-ischemic (30 days) periods of follow-up. There was also a statistically significant increase in the peak systolic and end diastolic velocity of blood flow as well as a decrease in the resistive index of retrobulbar arteries in those rats that underwent ischemia/reperfusion as compared to the controls.Long-term resveratrol use (2 months) has proved effective in improving ocular blood flow in a rat model of retinal ischemia/reperfusion injury.
- [Echocardiopgraphy in European tortoises (Testudo spp.)]. [English Abstract, Journal Article]
- Berl Munch Tierarztl Wochenschr 2016 Mar-Apr; 129(3-4):167-76.
An echocardiographic examination was carried out in 71 European tortoises (Testudo spp.) via the cervical-brachial acoustic windows. Simultaneously an electrocardiographic examination was performed. The inflow- and outflow tract of the heart were presented in frontal and sagittal longitudinal sections in B-mode. Within B-mode the size (diameter and area) of the atria and the ventricle (Cavum dorsale), the ventricular wall thickness and the diameter of the origin of the right aorta and of the right Arteria pulmonalis were measured. Also, the fractional shortening (FS%) and a fractional area shortening (FAS%) were calculated for the Cavum dorsale. Standard values for these cardiac parameters were determined for four different tortoise groups (depending on their carapace lengths). The direction of blood flow within the heart could be assessed via colour flow Doppler. By using pulsed-wave Doppler examinations of the inflow- and outflow tract the velocities, pressure gradients, velocity-time-integrals and acceleration- and deceleration times could be determined from the recorded inflow and outflow patterns and standard values were established for these parameters as well.
- Systolic and Diastolic Function in Congestive Heart Failure Pediatric Patients. [Journal Article, Research Support, Non-U.S. Gov't]
- Rom J Intern Med 2016 Jan-Mar; 54(1):37-46.
Two-dimensional (2D) and Doppler echocardiography are the main methods for the non-invasive evaluation of ventricular function in children. Our study monitored the evaluation of systolic and diastolic function in pediatric patients, using classical echocardiographic parameters and pulsed tissue Doppler parameters, as well as the correlation between these.The study included 18 healthy children and 9 children diagnosed with congestive heart failure secondary to congenital heart malformations. The parameters of systolic and diastolic function were measured by 2D echocardiography, 2D guided M mode, color and pulsed Doppler, as well as by pulsed tissue Doppler at the level of the mitral and tricuspid annulus.A relaxation alteration pattern or a pseudonormal pattern of E diastolic velocity compared to the A wave was found (E = A; E > A) in the group of subjects with heart failure. E wave deceleration time had significantly increased values in the case of patients with CHF, being correlated with diastolic dysfunction. Left ventricular flow propagation velocity Vp was decreased in patients with heart failure, the E/Vp ratio being maintained relatively constant in subjects with congestive heart failure and healthy subjects, most probably on account of the concomitant change in the E wave. Associations between the severity of systolic dysfunction and the diastolic dysfunction were found in pediatric patients diagnosed with congestive heart failure (Student test, p < 0.05).Tissue Doppler measurements proved to be useful for the evaluation of pediatric patients with altered ventricular geometry secondary to congenital heart disease, systolic-diastolic dysfunction and heart failure.
- [A Comparison Study on Early Damage Detection of Left Ventricular Function Based on Doppler Imaging Method for Children with Tumor]. [Comparative Study, English Abstract, Journal Article]
- Sheng Wu Yi Xue Gong Cheng Xue Za Zhi 2015 Dec; 32(6):1284-7.
The early damage detection and evaluation are of great significance in treatment and prognosis to the left ventricular function for children with tumor. In this paper, it is reported that the early damage of the left ventricular function was observed by pulsed wave Doppler (PWD) and tissue Doppler imaging (TDI) in our laboratory. Eighty children half a year to fourteen years old were included in this study. The cardiac function indices in chemotherapy group and control group were measured and compared. The results showed that there was significant difference in mitral and tricuspid annulus flow spectrum between the two groups. Compared with PWD,TDI is more prompt, objective and accurate in detecting early damage of left ventricular function in children with tumor. And TDI is a good method for early identification of ventricular function damage in children with tumor.
- Effect of Coronary Slow Flow on the Longitudinal Left Ventricular Function Assessed by 2-Dimensional Speckle-Tracking Echocardiography. [Journal Article]
- J Ultrasound Med 2016 Apr; 35(4):723-9.
The coronary slow flow phenomenon is defined as the slow progression of an angiographic contrast agent to the distal part of the coronary arteries on selective coronary angiography in the absence of stenosis. There are some studies with different results about the effect of this phenomenon on left ventricular (LV) function. The aim of our study was to evaluate the longitudinal LV function in the coronary slow flow phenomenon using 2-dimensional (2D) speckle-tracking echocardiography.In a study with a patient-to-patient matched design, 36 patients with the coronary slow flow phenomenon and 36 individuals with normal coronary flow matched for age (±5 years), sex, hypertension, and diabetes mellitus were compared in terms of the longitudinal LV systolic and diastolic functions by pulsed wave tissue Doppler echocardiography and 2D speckle-tracking echocardiography-derived indices.Lateral s' and e' waves were lower in the patients with the coronary slow flow phenomenon, but there were no statistically significant differences between the groups regarding the other tissue Doppler echocardiographic indices and longitudinal systolic strain and systolic and diastolic strain rates derived by 2D speckle-tracking echocardiography.Our results showed that the coronary slow flow phenomenon could not impair the longitudinal LV systolic and diastolic functions.
- Real-Time Detection of Periforaminal Vessels in the Cervical Spine: An Ultrasound Survey. [Journal Article]
- Reg Anesth Pain Med 2016 Mar-Apr; 41(2):130-4.
Compared with the thoracic and lumbar spine, transforaminal epidural injections and medial branch blocks in the cervical spine are associated with a higher incidence of neurological complications. Accidental breach of small periforaminal arteries has been implicated in many instances. In this observational study, using ultrasonography, we surveyed the incidence of periforaminal bloods vessels in the cervical spine.Patients undergoing ultrasound-guided cervical medial branch blocks were scanned using color power and pulsed wave Doppler. Five levels from C2/C3 to C6/C7 were studied. Incidental blood vessels located between the anterior tubercles of the transverses process and the posterior borders of the articular pillars were included for analysis. We recorded the diameter and position of arteries relative to contiguous bony landmarks as well the number of veins.In 102 patients, we performed a total 201 scans (1005 cervical levels). Of the 363 incidental vessels identified, 238 were arteries (mean diameter, 1.25 ± 0.45 mm). The latter were most commonly found at the posterior foraminal aspects of C5, C6, and C7 (13%, 11%, and 16% of scans, respectively); the transverse processes of C5 and C6 (10% and 16% of scans, respectively); and the articular pillars of C6 and C7 (19% and 16% of scans, respectively).Small periforaminal arteries are prevalent along the lateral aspect of the cervical spine, adjacent to areas commonly targeted by nerve block procedures. Further trials are required to determine if ultrasound guidance can reduce the incidence of complications related to accidental vascular breach.
- High-Frame-Rate Echocardiography Using Coherent Compounding With Doppler-Based Motion-Compensation. [Journal Article]
- IEEE Trans Med Imaging 2016 Jul; 35(7):1647-57.
High-frame-rate ultrasonography based on coherent compounding of unfocused beams can potentially transform the assessment of cardiac function. As it requires successive waves to be combined coherently, this approach is sensitive to high-velocity tissue motion. We investigated coherent compounding of tilted diverging waves, emitted from a 2.5 MHz clinical phased array transducer. To cope with high myocardial velocities, a triangle transmit sequence of diverging waves is proposed, combined with tissue Doppler imaging to perform motion compensation (MoCo). The compound sequence with integrated MoCo was adjusted from simulations and was tested in vitro and in vivo. Realistic myocardial velocities were analyzed in an in vitro spinning disk with anechoic cysts. While a 8 dB decrease (no motion versus high motion) was observed without MoCo, the contrast-to-noise ratio of the cysts was preserved with the MoCo approach. With this method, we could provide high-quality in vivo B-mode cardiac images with tissue Doppler at 250 frames per second. Although the septum and the anterior mitral leaflet were poorly apparent without MoCo, they became well perceptible and well contrasted with MoCo. The septal and lateral mitral annulus velocities determined by tissue Doppler were concordant with those measured by pulsed-wave Doppler with a clinical scanner (r(2)=0.7,y=0.9 x+0.5,N=60) . To conclude, high-contrast echo cardiographic B-mode and tissue Doppler images can be obtained with diverging beams when motion compensation is integrated in the coherent compounding process.
- Echocardiography-guided percutaneous per-ventricular laser ablation of ventricular septum: in vivo study in a canine model. [Journal Article]
- Lasers Med Sci 2016 May; 31(4):645-51.
Surgical myectomy and ethanol ablation are established intervention strategies for left ventricular outflow obstruction in hypertrophic cardiomyopathy. Safety and efficacy limitations of these interventions call for a minimally invasive, potentially safer, and more efficacious strategy. In this study, we aimed to evaluate the feasibility of echocardiography-guided percutaneous per-ventricular laser ablation of a ventricular septum in a canine model. Six domestic dogs were chosen for the study. A 21G needle was inserted into the right ventricle with its tip reaching the targeted basal to mid-septum, after which laser ablation was performed as follows: 1-W laser for 3 min (180 J) at the basal segment and 5 min (300 J) at middle segment of the septum, respectively. Echocardiography, blood chemistry tests, and pathology examination were performed to assess the results of laser ablation. No death or major complications, i.e., tamponade, pericardial effusion, or ventricular fibrillation, occurred. The laser-ablated areas were well demarcated in the results of the pathological examination. The diameters of the ablated regions were 4.42 ± 0.57 and 5.28 ± 0.83 mm for 3 and 5 min ablation, respectively. Pre-ablation and post-ablation, cardiac enzymes were found to increase significantly while no significant differences were found among M-mode, 2D (LVEF), pulsed-wave (PW) Doppler, and tissue Doppler imaging (TDI) measurements. Contrast echocardiography confirmed the perfusion defects in the ablated regions. Microscopically, the ablated myocardium showed coagulative changes and a sparse distribution of disappearing nuclei and an increase in eosinophil number were observed. Our study suggests that percutaneous and per-ventricular laser ablation of the septum is feasible, potentially safe and efficacious, and warrants further investigation and validation.