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At least 253 records · Page 14Linked to original sources

PubMed2003

Post systolic shortening in nonobstructive hypertrophic cardiomyopathy with delayed emptying of the apex: a Doppler flow, tissue Doppler and strain rate imaging case study.

We report a case of a 92-year-old woman with syncope and exertional dyspnea, who on echocardiographic examination proved to have hypertrophic cardiomyopathy. Doppler flow revealed delayed emptying of the apex, extending into the early filling phase. Tissue Doppler and strain rate imaging illustrated postsystolic shortening corresponding to the apical ejection, demonstrating that the apical flow was due to wall thickening resulting in active ejection. The imaging methods and mechanics of post-systolic shortening are discussed.

Aged↗

PubMed2002

Mitral inflow and mitral annular motion velocities in patients with mitral annular calcification: evaluation by pulsed Doppler echocardiography and pulsed Doppler tissue imaging.

AIMS: We evaluated the relationship between the mitral inflow velocities by pulsed Doppler echocardiography and mitral annular motion velocities by pulsed Doppler tissue imaging in patients with mitral annular calcification. METHODS AND RESULTS: Fifty-three patients with mitral annular calcification were divided into two groups: severe mitral annular calcification (n=15, mitral annular calcification bigger than or equal 5mm in width) and mild mitral annular calcification (n=38, mitral annular calcification <5mm in width). In addition, 20 patients with hypertensive heart disease (HHD group) and mild left ventricular hypertrophy but no mitral annular calcification and 30 normal individuals (normal group) were studied. The early diastolic mitral inflow velocity (E) was higher in the severe mitral annular calcification group (0.75+/-0.26 m/s) than in the HHD and normal groups (mild mitral annular calcification, 0.65+/-0.21; HHD, 0.57+/-0.24; normal, 0.55+/-0.15m/s), and the late diastolic mitral inflow velocity (A) was higher in the severe mitral annular calcification group (1.24+/-0.23 m/s) than in the other three groups (mild mitral annular calcification, 0.96+/-0.20; HHD, 0.84+/-0.23; normal, 0.75+/-0.13 m/s). In contrast, the early and late diastolic annular velocities (Ea, Aa) were lower in the severe mitral annular calcification group (Ea: 5.7+/-2.2; Aa: 11.9+/-4.4 cm/s) than in the other three groups (Ea: mild mitral annular calcification, 8.3+/-2.5; HHD, 7.7+/-2.2; normal, 9.0+/-1.8 cm/s; Aa: mild mitral annular calcification, 14.2+/-4.1; HHD, 14.3+/-2.8; normal, 14.2+/-2.1cm/s). Mitral valve area was smaller in the severe mitral annular calcification group (2.6+/-1.0 cm(2)) than in the other three groups (mild mitral annular calcification, 3.1+/-0.7; HHD, 4.1+/-0.7; normal, 4.2+/-0.9 cm(2)). In the mitral annular calcification and normal groups, the A correlated inversely with mitral valve area (r=-0.67, P<0.01) and directly with severity of mitral annular calcification (r=0.65, P<0.01), and the Ea correlated inversely with left ventricular wall thickness (r=-0.37, P<0.01) and severity of mitral annular calcification (r=-0.45, P<0.01). CONCLUSION: Patients with severe mitral annular calcification have higher mitral inflow velocities due to mitral annular restriction and lower mitral annular velocities caused by decreased mitral annular motion and abnormal left ventricular relaxation.

Aged↗

PubMed1996

[Measuring basilar artery blood flow velocity with transcranial Doppler and and transcranial Doppler color ultrasound].

GOAL: The aim of the present study was to clarify, by means of transcranial colour-coded duplex sonography of the basilar artery, whether there are changes in basilar artery blood flow in patients with acute inner ear disturbances and whether the flow in the basilar artery is affected by acoustic stimuli in such patients and in normal, healthy controls. METHOD: Basilar artery blood flow velocity was measured in 52 patients with severe inner ear impairment over a period of two weeks by means of conventional transcranial Doppler sonography and transcranial colour-coded duplex sonography. The same measurements were carried out in 45 healthy control subjects. At the end of the two week period, both patients and controls were exposed to 70-dB noise, with basilar artery flow evaluated before and during exposure. The basilar artery Doppler curves were analysed for systolic flow velocity, end-diastolic flow velocity, resistance index (Pourcelot) and pulsatility index (Gosling). RESULTS: During the first two days of the study, the basilar artery resistance index and pulsatility index were significantly (p < 0.001) higher in patients than in controls. During noise exposure, both patients and controls showed significant (p < 0.01) increases in these indices. CONCLUSION: This study shows that temporary increases in the basilar artery resistance index and pulsatility index are found both in the acute phase of inner ear disease and during exposure to noise.

Acoustic Stimulation↗

PubMed1995

Efficacy of Ibudilast on lower limb circulation of diabetic patients with minimally impaired baseline flow: a study using color Doppler ultrasonography and laser Doppler flowmetry.

Ibudilast is a prostacyclin-mediated vasodilator and antiplatelet agent. The hemodynamic effects of ibudilast were evaluated in 41 patients with non-insulin-dependent diabetes mellitus by means of two-dimensional Doppler ultrasonography and laser Doppler blood flowmetry. Before and one hour after oral administration of ibudilast (10 mg), or elastase (1800 U) as a control, the cross-sectional area (CSA) of the dorsal pedis artery, its blood flow index (BFI), and dermal microcirculatory blood volume (MBV) were measured. In the ibudilast group, all of the parameters (CSA, BFI, and MBV) significantly increased as compared with the elastase group. These data suggest that ibudilast is effective in ameliorating diabetic macroangiopathy and microangiopathy of the lower limbs.

Administration, Oral↗

PubMed2005

Comparative value of tissue Doppler imaging and m-mode color Doppler mitral flow propagation velocity for the evaluation of left ventricular filling pressure.

BACKGROUND: Recently, two new indexes based on the ratio of transmitral early diastolic velocity (E) to tissue Doppler imaging (TDI), and early diastolic velocity of mitral annulus (E') and E to propagation velocity (Vp) have been proposed to predict left ventricular (LV) filling pressures. However, little is known about the comparative value of these two indexes. METHODS: We studied 71 consecutive patients referred for coronary angiography (mean age +/- SD, 65 + 11 years; 21 patients with LV ejection fraction [EF] < 50%). Complete Doppler echocardiographic examination including TDI and Vp measurements and direct measurement of LV end-diastolic pressure (LVEDP) were performed simultaneously in the catheterization laboratory. LV filling pressures were considered elevated when LVEDP was > or = 15 mm Hg. RESULTS: The correlation coefficients between E/E' and E/Vp and LVEDP were 0.68 (p = 0.01) and 0.54 (p = 0.01), respectively, in the overall population. The correlations were better in patients with low LV EF (< 50%) [0.8 (p = 0.01) and 0.77(p = 0.01)] and poor in patients with normal LV EF (0.57 [p = 0.05] and 0.41 [not significant]), respectively. Moreover, Vp measurements had higher interobserver variability compared to E' (14% vs 7%). The cutoff values for both indexes giving the best sensitivity and specificity in identifying LVEDP > or = 15 mm Hg were 9 for (E/E') and 2 for (E/Vp). CONCLUSION: Both E/E' and E/Vp can be used for the evaluation of LV filling pressures. However, the sensitivity of these indexes, especially E/Vp, is hampered by EF. E/E' has a lower variability than Vp and should be preferred for estimation of filling pressures especially in patients with EF > 50%.

Aged↗

PubMed2000

[Ultrasonographic diagnosis of venous thrombosis: color Doppler and power Doppler].

Eco color-Doppler (ECD) and Power Doppler (PD) currently allow an accurate and early diagnosis of deep venous thrombosis (DVT). "Ecocontrasts" boost sensitivity. The simple test of ultrasound probe compression shows excellent sensitivity in the proximal venous segments, comparable to a full ECD: the latter is preferable for distal segments. Ultrasound probe compression is not sufficient as the sole test when studying suspected leg DVT, but may form an integral part of a complete ECD study. The accuracy of ECD used in segments that are difficult to evaluate (iliac axes, inferior vena cava) has improved considerably thanks to PD. At these levels, it is certainly not possible to use ultrasound probe compression alone. The same is true for the diagnosis of recidivation, where a complete ECD is required to evaluate thrombotic overlap indicating true rethrombosis of partial or fully recanalised blood vessels. Phlebography no longer represents the gold standard for diagnosis compared to ultrasound techniques. Its use is limited to discriminating between genuinely doubtful and discordant cases of DVT and the search for occult embolic sources in patients with severe pulmonary embolism. The usefulness of an extensive study of venous vessels is gaining increasing confirmation, using the full potential of eco-Duplex methods in the systematic search for thrombotic lesions. The possibility of obtaining as much information as possible during the first complete scan reduces the costs of the procedure and is more accurate for the diagnosis of suspected DVT recidivation.

Anticoagulants↗

PubMed1994

[Combined color Doppler and pulsed Doppler in the diagnosis of small hepatocellular carcinomas].

The combined studies by using color Doppler (CD) and pulsed Doppler (PD) technique in 56 patients with 71 solid hepatic lesions smaller than 3 cm in diameter were carried out. The detecting rates of arterial signals in small hepatocellular carcinomas (sHCC) group, hepatic cavernous hemangiomas (HCH) group and others group were 86.9%, 37% and 33% respectively. Whereas, the average value of resistance index (RI) in sHCC group was very higher than that in other groups. By using combined CD and PD space-taking lesions of the liver are tentatively diagnosed as sHCC under conditions of color flow, arterial signals, and a RI of more than 50%. The specificity (96%) and accuracy (90%) of the diagnosis superior to the conventional US (P < 0.005).

Carcinoma, Hepatocellular↗

PubMed1997

Inter-examiner variability of transcranial Doppler procedure and reports: a multicenter survey. Italian Transcranial Doppler Group.

OBJECTIVE: To assess the clinical use of Transcranial Doppler (TCD) and the reproducibility of TCD reports. METHODS: A multicenter survey involving 45 Italian laboratories (the Italian Transcranial Doppler Group-ITDG) was carried out by investigating the examination procedure, the parameters and normative data, and the interpretation criteria applied to reach diagnostic conclusions. The inter-examiner agreement on 10 TCD reports was computed using Kappa statistics. Results. Investigators consider both qualitative (flow direction, signal detectability) and quantitative measurements (mean flow velocity and pulsatility index values), applying their own normative criteria reference which may differ slightly between centers. TCD reports appear to be highly reproducible when based upon the interpretation of qualitative data (Kappa index: 0.95-1.00), whereas a moderate agreement is obtained when considering alterations in quantitative parameters (Kappa: 0.44-0.81). CONCLUSIONS: The application of the same criteria in different laboratories may facilitate the standardization of TCD examinations and support the reproducibility of clinical reports based on TCD parameters.

Aged↗

PubMed2004

Myocardial tissue motion influence on laser Doppler perfusion monitoring using tissue Doppler imaging.

Tissue motion of the beating heart generates large movement artifacts in the laser Doppler perfusion monitoring (LDPM) signal. The aim of the study was to use tissue Doppler imaging (TDI) to localise intervals during the cardiac cycle where the influence of movement artifacts on the LDPM signal is minimum. TDI velocities and LDPM signals were investigated on three calves, for normal heartbeat and during occlusion of the left anterior descending coronary artery. Intervals of low tissue velocity (TDIint, < 1 cm s(-1)) during the cardiac cycle were identified. During occlusion, these intervals were compared with low LDPM signal intervals (LDPMint, <50% compared with baseline). Low-velocity intervals were found in late systole (normal and occlusion) and late diastole (normal). Systolic intervals were longer and less sensitive to heart rate variation compared with diastolic ones. The overlap between LDPMint and TDIint in relation to TDIint length was 84+/-27% (n = 14). The LDPM signal was significantly (p < 0.001, n = 14) lower during occlusion if calculated during minimum tissue motion (inside TDIint), compared with averaging over the entire cardiac cycle without taking tissue motion into consideration. In conclusion, movement artifacts are reduced if the LDPM signal is correlated to the ECG and investigated during minimum wall motion. The optimum interval depends on the application; late systole and late diastole can be used.

Animals↗

PubMed1998

Reliability of color Doppler and power Doppler sonography in the evaluation of intussuscepted bowel viability.

In two similar cases of irreducible intussusception with wall necrosis and perforation, symptoms had begun 24 h before admission and the plain radiographs showed signs of small-bowel obstruction. The sonographic (US) appearances, however, were different: color Doppler (CD) US showed vascular flow in the intussuscepted bowel in one case and no flow in the other. After radio-clinical assessment, both children underwent surgery and an intestinal resection had to be performed, manual reduction being impossible. The reliability of the US findings and the prognostic value of CD and power Doppler US in determining the viability of the intussuscepted bowel are discussed with a review of the literature.

Anastomosis, Surgical↗

PubMed1980

Transcutaneous Doppler method of measuring cardiac output--II. Noninvasive measurement by transcutaneous Doppler aortic blood velocity integration and M mode echocardiography.

In 15 patients with acute myocardial infarction (group I) and in 14 patients undergoing routine cardiac catheterization (group II) cardiac output values obtained by multiplying the 1 minute sum of the systolic integral of aortic blood flow velocity by the average systolic diameter of the aortic root were compared with values obtained with the thermodilution and Fick methods, respetively. Patients in group I were studied under various hemodynamic conditions, whereas those in group II were studied in the baseline state conditions, whereas those in group II were studied in the baseline state only. In group I, the correlation between the two methods was excellent (r values ranged from 0.96 to 0.99) except in one severely anemic patient whose Doppler signals were noisy, but at heart rates exceeding 150 beats/min it was not as good. In group II, the correlatin between the two methods was r = 0.96 with a standard error of the estimate of 0.226 liter. The Doppler method is totally noninvasive and is useful for monitoring changes in cardiac output in patients with acute myocardial infarction.

Adult↗

PubMed1988

Doppler echocardiographic flow characteristics of isolated patent ductus arteriosus: better delineation by Doppler color flow mapping.

Eighteen infants and children with isolated ductus arteriosus and various hemodynamic states were examined with the Doppler color flow mapping technique to study the flow patterns of the patent ductus and its adjacent structures. Direct visualization of the ductus was achieved in all patients. All ductal flow was shunting left to right from the descending aorta to the pulmonary artery even in the presence of significant elevation of pulmonary artery pressure. However, transient bidirectional shunting was observed in two patients on serial studies. Disturbed systolic and diastolic flows were demonstrated within the ductus in each case. The blood flows in the main pulmonary artery consisted of three distinguishable areas: 1) a characteristic high velocity turbulent retrograde ductal jet throughout the entire cardiac cycle, located in the anterolateral aspect of the main pulmonary artery; 2) nonspecific low velocity retrograde late systolic and early diastolic flow, located in the posteromedial aspect of the main pulmonary artery; and 3) low velocity forward systolic and diastolic flow, occupying the remaining area of the pulmonary artery. The blood flows in the descending aorta near the ductal orifice consisted of disturbed systolic and diastolic flows in a reversed direction. By providing detailed real time blood flow information with simultaneous imaging of the ductus, Doppler color flow mapping greatly facilitates the detection of a small ductal shunt. This technique also allows detection of a bidirectional or right to left ductal shunt.

Aorta↗

PubMed2006

Doppler tissue imaging in the assessment of atrioventricular conduction time: validation of a novel technique and comparison with electrophysiologic and pulsed wave Doppler-derived equivalents in an animal model.

Accurate assessment of atrioventricular conduction time (AVCT) is crucial for early detection of evolving fetal heart block. Simultaneous pulsed wave Doppler (PD) interrogation of left ventricular inflow and outflow is mainly used to study fetal AVCT. Limitations of this modality include its dependency on loading conditions and merging early and late diastolic inflow waves at faster heart rate (HR). Sequential analysis of atrioventricular myocardial motion by Doppler tissue imaging (DTI) might be more useful in this regard. In 15 open-chest pigs, AVCT was measured by PD, DTI, and electrocardiogram at baseline HR and during incremental atrial pacing up to 200 beats/min. Electromechanical delay and pre-ejection period were assessed at baseline and maximal HR. DTI-derived AVCT correlated better with PR intervals and allowed measurements at faster HRs than did PD (P < .05). Pre-ejection period prolonged with faster HR (P < .001), unlike electromechanical delay. In conclusion, DTI allows more accurate measurement of AVCT over a wider HR range than does PD.

Animals↗

PubMed1997

Quantitative tissue Doppler in comparison with two-dimensional and Doppler echocardiographic indices in normal subjects.

To assess normal values of left ventricular wall motion velocities with respect to sequential phases of the cardiac cycle 95 normal subjects (mean age 34+/-12 years) were examined using a recently developed method based on the computer software TDI-LaborR enabling a variable time and space related measurement of regional wall velocity from tissue Doppler (TD) images. The study population consisted of three age groups: 16-29 years (group 1, n=34 (36%)), 30-49 years (group 2, n=45 (49%)), >50 years (group 3, n=16 (17%)). Using TD M-mode of the left ventricular posterior wall the mean subendocardial and subepicardial velocity as well as the transmural myocardial velocity were determined for the rapid, slow and atrial filling phases as well as the systole. In addition, standard mitral inflow parameters-E and A velocities were determined by pulsed Doppler echocardiography. The left parasternal window was used. The subendocardial rapid filling and atrial filling myocardial velocity were found to be age significantly dependent. The myocardial rapid filling were correlated to early diastolic mitral inflow velocity and to the ratio of early and atrial flow velocities (r ranges from 0.23 to 0.36, P<0.01). We conclude that aging is accompanied by an increase of atrial filling compensating a reduced myocardial relaxation already before 50 years. Whereas mitral inflow velocities reflect diastolic function indirectly, it is directly indicated by TD myocardial velocity parameters.

Adolescent↗

PubMed1998

Quantification of mitral and tricuspid regurgitation by the proximal flow convergence method using two-dimensional colour Doppler and colour Doppler M-mode: influence of the mechanism of regurgitation.

In patients with mitral (n=77: organic=49, functional=28) and tricuspid regurgitation (n=55: functional=54) quantified by angiography, the temporal variation of the proximal flow convergence region throughout systole was assessed by colour Doppler M-Mode, and peak and mean radius of the proximal isovelocity surface area for 28 cm/s blood flow velocity were measured. Additionally, the peak radius derived from two-dimensional colour Doppler was obtained. About 50% of the patients with mitral and tricuspid regurgitation showed a typical temporal variation of the flow convergence region related to the mechanism of regurgitation. The different proximal isovelocity surface area radii were similarly correlated to the angiographic grade in mitral and tricuspid regurgitation (rank correlation coefficients 0.55-0.89) and they differentiated mild to moderate (grade < or =II) from severe (grade > or =III) mitral and tricuspid regurgitation with comparable accuracy (82-96%). However, moderate mitral regurgitation due to leaflet prolapse in two patients was correctly classified by the mean M-mode radius and overestimated by both peak radii. Only half of the patients showed a typical variation of the flow convergence region related to the mechanism of regurgitation. The different proximal isovelocity surface area radii were suitable to quantify mitral and tricuspid regurgitation in most patients. However, in mitral regurgitation due to leaflet prolapse the use of the mean M-mode radius may avoid overestimation.

Adult↗

PubMed1994

Comparison of laser Doppler perfusion imaging, laser Doppler flowmetry, and thermographic imaging for assessment of blood flow in human skin.

In this study we compared three non-invasive methods of measuring skin perfusion, thermographic imaging (TI), laser Doppler flowmetry (LDF) and the new technique of laser Doppler imaging (LDI). Seven normal volunteers were studied in a temperature-controlled room with an ambient temperature of 22 +/- 1 degree C. Images of the left hand were recorded using LDI followed by TI. LDF was then used on two standard locations on the fingers and back of the hand. The measurements were then repeated for a hot (37 degrees C) and then a cold (10 degrees C) challenge. A significant linear correlation (r = 0.960, p < 0.01, with 95% confidence limit of 0.35-0.77, n = 38) was found between LDF and LDI. However, LDF and LDI did not correlate well with TI (r = 0.577, p < 0.01, with 95% confidence limit of 0.32-0.76, n = 38). The LDI method was found to be highly reproducible (mean +/- 1 SD; 625 +/- 30, with coefficient of variation 5%). The blood flow and temperature distribution of skin of the hand was then recorded using TI and LDI in 10 patients (mean age +/- SD, 41.7 +/- 9.9) with scleroderma and eight normal volunteers (mean age +/- SD, 30.6 +/- 6.5). The overall mean blood flow and temperature in the hands of patients with scleroderma (mean +/- SD 444 +/- 265 flux, 29.3 +/- 3.3 degrees C) was significantly (p < 0.0001) lower compared with the normal volunteers (mean +/- SD, 912 +/- 390 flux, 34.0 +/- 3.2 degrees).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1998

Transcranial Doppler ultrasonographic features during drug withdrawal from drug-induced headache. A transcranial Doppler follow-up study.

BACKGROUND: A vascular component in ergotamine-induced headache has been proposed. No study has been carried out to evaluate cerebral hemodynamic changes by means of transcranial Doppler during withdrawal from migraine medication; in particular, ergotamine-containing drugs. METHOD: We examined 21 patients suffering from drug-induced headache during their in-hospital withdrawal from ergotamine (n=8) and compared them with patients during withdrawal from analgesics (n=13) and with healthy controls (n=14). Cerebral blood flow velocities were measured with transcranial Doppler, and pulsatility indices were calculated. Blood pressure, heart rate, and end-tidal carbon dioxide were documented. A subjective analog headache rating scaling was used for day-to-day evaluation of headache severity. RESULTS: Mean cerebral blood flow velocities dropped significantly after discontinuation of ergotamine-containing drugs but not after stopping common analgesics. Pulsatility indices remained unchanged. Cerebral blood flow velocities were higher in drug-ingesting patients compared to the control group and showed significant changes in patients with headache using ergotamine and in those using analgesics. Carbon dioxide, heart rate, and blood pressure remained unchanged. The headache rating scale did not show a constant trend. COMMENTS: Our results indicate that ergotamine and, to a lesser extent, common analgesics including caffeine might influence cerebral blood flow velocities and pulsatility indices causing transient and reversible disturbance of cerebral autoregulation.

Adult↗

PubMed2000

Angiographical and Doppler flow-derived parameters for assessment of coronary lesion severity and its relation to the result of exercise electrocardiography. DEBATE study group. Doppler Endpoints Balloon Angioplasty Trial Europe.

AIMS: Evaluation of angiographical and intracoronary Doppler-derived parameters of coronary stenosis severity. METHODS AND RESULTS: A total of 225 patients with one-vessel disease were studied before PTCA and at 6 months follow-up. Exercise electrocardiography was performed to document presence (n = 157) or absence (n = 138) of an ST segment shift (> or =0.1 mV). Intracoronary blood flow velocity analysis was performed to determine the proximal/distal flow velocity ratio, the distal diastolic/systolic flow velocity ratio and coronary flow velocity reserve. Receiver operator characteristic curves were calculated to assess the predictive value of these variables compared with the exercise test. The distal coronary flow velocity reserve demonstrated the best linear correlation for both percentage diameter stenosis and minimum lumen diameter (r = 0.67 and r = 0.66; P<0.01), compared to the diastolic/systolic flow velocity ratio (r = 0.19 and r = 0.14; P<0.01) and the proximal/distal flow velocity ratio (r = 0.03 and r = 0.07; not significant). The areas under the curve were 0. 84+/-0.02; 0.82+/-0.03 and 0.83+/-0.03 for diameter stenosis, minimum lumen diameter and coronary flow velocity reserve, respectively. Logistic regression analysis revealed that the percentage diameter stenosis or minimum lumen diameter and coronary flow velocity reserve were independent predictors for the result of stress testing. CONCLUSIONS: The distal coronary flow velocity reserve is the best intracoronary Doppler parameter for evaluation of coronary narrowings. Angiographical estimates of coronary lesion severity and distal coronary flow velocity reserve are good and independent predictors for the assessment of functional severity of coronary stenosis, emphasizing the complementary role of these parameters for clinical decision making.

Adult↗