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At least 109 records · Page 6Linked to original sources

PubMed1999

Right ventricular diastolic filling assessed by conventional doppler and tissue Doppler imaging in normal children.

To examine age-related changes in right ventricular filling dynamics, we performed conventional pulsed Doppler (n=99) and tissue Doppler (n=30) echocardiographic studies in normal subjects aged 7 days to 273 months. The tricuspid flow velocity during early diastole (peak E) wave correlated significantly but weakly with the logarithm of age. The peak E wave in the early neonatal period was almost 80% of the older children's values and increased to 100% by 36 months of age. In the right ventricular tissue Doppler imaging, the peak myocardial velocity during early diastole also increased significantly with the logarithm of age. However, the tissue Doppler peak A did not change with age. There was a significant correlation between the tissue Doppler peak E wave and the tricuspid peak E wave and between the tissue Doppler peak E/A wave and the tricuspid peak E/A wave. The age-related changes in the tricuspid inflow velocity patterns were similar to the age-related alterations in the right ventricular myocardial velocity patterns. Age-related changes in the tricuspid inflow velocity and myocardial velocity patterns may be related to age-related maturation in the right ventricular diastolic performance.

Adolescent↗

PubMed1998

Usefulness of Doppler spectral analysis and power Doppler sonography in the differentiation of cervical lymphadenopathies.

OBJECTIVE: Our purpose was to depict the characteristics of the global vasculature of cervical lymphadenopathies and to clarify the efficiency of Doppler spectral analysis and power Doppler sonography in the differential diagnosis. SUBJECTS AND METHODS: Prospectively, 289 lymph node lesions underwent Doppler flow studies and were grouped as metastasis, lymphoma, tuberculosis, and benign lymphadenopathies. Sonographic assessments included vascular pattern and vascular density (presented as vascularity index) as revealed by power Doppler sonography. Vascular resistive index and pulsatility index were assessed by at least three flow samplings. Values of both the highest and the lowest resistance were analyzed. Vascularity index, resistive index, pulsatility index, nodal size, and age were correlated. RESULTS: Most benign lymphadenopathies (87%), tuberculous lymphadenopathies (72%), and lymphomas (71%) revealed an avascular or hilar vascular pattern. Vascular patterns of most metastatic lymphadenopathies (90%) were of spotted (26%), peripheral (11%), or mixed (53%) type. The vascularity indexes of metastatic lymphadenopathy (mean, 0.176) and lymphoma (mean, 0.122) were significantly higher than those of tuberculous and benign lymphadenopathy (mean, 0.054 and 0.042, respectively). In vascular resistance studies, the highest pulsatility index and resistive index in metastatic lymphadenopathy statistically exceeded those of benign lymphadenopathy, whereas no difference was found in the lowest values. Negative correlation was found between the vascularity index of metastatic lesions and their lowest vascular resistance, and positive correlation was found between vascularity index and nodal size in benign lymphadenopathies. CONCLUSION: In addition to vascular resistance assessed traditionally with Doppler spectral analysis, vascular pattern and vascular density assessed with power Doppler sonography can better differentiate the nature of lymphadenopathies.

Adolescent↗

PubMed1998

Diffuse prostatic lesions: role of color Doppler and power Doppler ultrasonography.

The purpose of this study was to assess the role of color Doppler ultrasonography and power Doppler ultrasonography in the identification of diffuse prostatic lesions. Forty male patients underwent gray scale transrectal ultrasonography, color and power Doppler sonography, and transrectal ultrasonographically guided biopsy. Transrectal ultrasonographically guided biopsy revealed cancer in 23 patients and benign lesions in 17 patients. Among the prostatic cancers 82.6% (19 of 23) showed increased flow signals, whereas 23.5% (four of 17) of benign lesions showed increased flow signals on color or power Doppler ultrasonography. If we consider increased flow signal on color or power Doppler sonography as a sign of a prostate cancer in diffuse prostatic lesions, these modalities have a sensitivity of 82.6%, specificity of 76.5%, and positive predictive value of 82.6%. On the basis of our study, we may conclude that color and power Doppler ultrasonography are useful in the identification of diffuse prostatic lesions.

Adult↗

PubMed2002

What can Doppler wave forms of the left internal thoracic artery teach us? -The efficacy of apical transthoracic approach of Doppler echocardiography-.

The Doppler wave form along the proximal left internal thoracic artery (LITA), which is detected by the parasternal or suplaclavicular view, shows a different pattern from that of the distal side of the LITA due to the effect of blood pulsatility from the subclavian artery. We evaluated postoperative LITA function immediately after surgery with an apical approach of transthoracic pulsed Doppler echocardiography in 124 patients and compared its results with that of one month postoperative Doppler findings and graft angiogram. The LITA was effectively detected and good quality Doppler waveforms obtained in 120 (96.8%) patients. The LITA diameter was significantly enlarged in the first month after surgery compared with that of the postoperative early phase (1.99 0.31 vs. 1.71 0.72 mm, p<0.05). The diastolic peak velocity and diastolic/systolic velocity ratio (D/S) in the postoperative early phase were 0.26 0.08 m/sec. and 1.54 0.04, respectively. These results were unchanged one month postoperatively. In graft angiography, all LITAs were patent, but three types of abnormal findings around the anastomosis such as string sign, anastomotic stenosis, and distal native coronary stenosis were indicated in 6 (5.5%) patients. The Doppler study in these patients showed decreasing diastolic peak velocity and D/S of less than 1.0. LITA Doppler wave with D/S of more than 1.0 was associated with a good angiographic finding. This technique was considered not only noninvasive but also noninfective method for postoperative early graft assessment.

Aged↗

PubMedDate not supplied

Assessment of portal hemodynamics by ultrasound color Doppler and laser Doppler velocimetry in liver cirrhosis.

BACKGROUND: Color Doppler is a noninvasive method for assessing portal hemodynamics. Laser Doppler velocimetry is useful in assessment of microcirculatory abnormalities in portal hypertensive gastropathy (PHG). AIMS: To study portal hemodynamics by color Doppler and gastric mucosal blood flow (GMBF) by laser Doppler velocimetry in patients with cirrhosis. METHODS: Twenty-eight patients with cirrhosis of liver (24 men) and 10 healthy subjects (7 men) were studied. Portal venous blood flow (PVBF) and portal flow velocity (PFV) were assessed by color Doppler at the level where the hepatic artery crosses the portal vein, and GMBF was measured by laser Doppler velocimetry. RESULTS: PVBF (379.5 [102.9] mL/min), PFV (5.3 [1.1] cm/sec) and GMBF (3.5 [0.8] volts) were significantly lower in patients with cirrhosis than in controls. PVBF and PFV were significantly lower in patients in Child class B and C than those in class A. Patients with ascites had significantly lower PVBF, PFV and GMBF than those without; values were also lower in patients with PHG than in those without. History of bleeding had no relation with PVBF and PFV. GMBF showed good correlation with PVBF (r=0.58, p<0.001) and with PFV (r=0.48, p<0.01). CONCLUSIONS: In cirrhosis of liver, PVBF, PFV and GMBF are significantly lower, and the changes increase with increasing severity of liver disease.

Adult↗

PubMed2001

Comparison of conventional color Doppler imaging and power doppler imaging for the diagnosis of ovarian cancer: results of a European study.

OBJECTIVE: The purpose of this prospective study was to compare the diagnostic accuracy of conventional color Doppler (CCD) imaging and power Doppler (PD) imaging in the diagnosis of ovarian cancer. METHODS: Six hundred fifty-six consecutive women with adnexal masses scheduled for surgery in two European university departments of obstetrics and gynecology underwent preoperative transvaginal ultrasound. The scanning procedure was the same in the two institutions: after B-mode sonography, a CCD/PD imaging scan was performed before pulsed Doppler evaluation. Using both modalities of color Doppler, malignancy was suspected when arterial flow was visualized in an echogenic portion defined as malignant by B-mode. To avoid the risk of bias due to the absence of blindness of the examiner after the first Doppler evaluation, at one institution 328 consecutive women with an adnexal mass were evaluated using only CCD imaging, whereas at the second institution the ultrasonographic evaluation of the same number of masses was performed using PD imaging, and the results were compared prospectively. RESULTS: The age, the rate of postmenopausal women, and the rate of ovarian cancer were similar in the two institutions. The false-positive rate of B-mode imaging was similar in the two institutions (17 versus 18%), while the false-positive rates of CCD and PD imaging were 4.6 and 7.4%, respectively. Although the overall diagnostic accuracy of two techniques seems comparable, with a similar value of K (0.81 versus 0.84), a significantly lower sensitivity in differentiation of benign from malignant ovarian lesions was found using CCD (87 versus 100%). CONCLUSIONS: At least one of the two Doppler techniques should be used in conjunction with B-mode imaging in order to decrease the false-positive rate of B-mode used alone but CCD imaging showed a higher false-negative rate.

Adult↗

PubMedDate not supplied

Comparison of the tissue Doppler-derived left ventricular Tei index to that obtained by pulse Doppler in patients with congenital and acquired heart disease.

We compared the left ventricular Tei index measured by tissue Doppler imaging (TDI) to that obtained by pulsed Doppler (PW) in patients with congenital heart disease. In 40 consecutive patients with a variety of congenital and acquired heart diseases, the left ventricular (LV) PW Doppler-derived Tei index was assessed on-line as previously described. TDI-derived anatomic curved M-mode and the unprocessed velocity trace from the basal septum were used to time the opening and closure of the mitral and aortic valves in one cardiac cycle, respectively. The TDI Tei index was calculated off-line according to the equation (isovolumetric relaxation time + isovolumetric contraction time)/ ejection time. The Tei index calculated from TDI correlated significantly with that measured by pulsed Doppler (r = 0.92, p = 0.001). The mean difference (range) between pulsed Doppler-derived Tei index and TDI-derived Tei index was 0.005 (-0.07-0.06), which was within the limits of agreements. Interobserver variability for the TDI-derived Tei index was 5 +/- 3%. The TDI Tei index can be used to assess the global LV function in patients with congenital heart disease. In contrast to the PW Doppler-derived Tei index, the TDI-derived Tei index obtained from the same cardiac cycle may help to differentiate systolic from diastolic dysfunction by providing specific information on the isovolumetric intervals.

Adolescent↗

PubMed1980

Transcutaneous method of measuring Doppler cardiac output--I. Comparison of transcutaneous and juxta-aortic Doppler velocity signals with catheter and cuff electromagnetic flowmeter measurements in closed and open chest dogs.

Cardiac output values obtained by thermodilution technique in 20 closed and open chest dogs were compared with values obtained by multiplying the integral of Doppler systolic velocity signals of aortic flow in 1 minute by the cross-sectional area of the aortic root. Doppler velocity signals were measured either from immediately outside the proximal aortic wall or from outside the chest wall during (1) the baseline state, (2) after 500 ml of hemorrhage, and (3) after reinfusion, (4) after administration of propranolol, and (5) during infusion of dopamine. In addition, Doppler "stroke volume" waveforms were compared with those obtained by electromagnetic flowmeter. Results showed a close similarity between Doppler signals and electromagnetic waveforms, and a close correlatin between Doppler and thermodilution values for cardiac output except at heart rates exceeding 160 beats/min. The studies showed the transcutaneous Doppler method of measuring cardiac output to be an accurate and reliable technique with application to clinical heart disease.

Animals↗

PubMed1991

Experimental study of the effects of pulsed Doppler sample volume size and position on the Doppler spectrum.

With a pulsed Doppler system, the recorded Doppler spectrum is expected to vary depending upon the sample volume size relative to the diameter of the vessel, the position of the sample volume in the vessel and the velocity profile. In the in vitro experiments described in this paper, the velocity profile was kept constant by using steady parabolic flow in a flow model. As the Doppler sample volume size and position were changed, the maximum variations of quantitative measurements from the Doppler spectrum were determined. The maximum, mean and mode frequencies and spectral broadening index (SBI) were affected by the position of the sample volume but to a lesser degree by its length (1.5-5.0 mm) relative to the 9.5 mm beam path length across the tube. When the centre of the Doppler sample volume was moved within the central 25% of the tube, the maximum variations were as follows: maximum frequency 3-5%, mean frequency 8-9%, mode frequency 8-9% and SBI 16-18%, where the range indicates the effect of increasing the sample volume size. Based on these results obtained under steady flow conditions in vitro, it is concluded that quantification of pulsed Doppler spectra may be feasible if the sample volume is positioned within the central 25% of the vessel.

Blood Flow Velocity↗

PubMed1993

Limitations of color flow Doppler imaging in the quantification of valvular regurgitation: velocity of regurgitant jet, rather than volume, determines size of color Doppler image.

The objective of this study was to determine the validity of estimation of regurgitant volume by visual assessment of color flow Doppler display. An experimental apparatus was designed that is capable of ejecting precise volumes of echogenic material from one chamber to another under continuous color flow Doppler monitoring. The velocity of flow was altered independently by changing either the size of the orifice through which flow occurred or the ejection rate. In this manner the differential effects of volume and velocity on the color flow Doppler image could be examined. The maximum area encompassed by the color flow Doppler pattern for each ejection was planimetered by using commercially available on-line software. In addition the reviewer in each case applied a subjective grade to the appearance of the color flow jet (1+ to 4+). Comparison was then made of the color flow Doppler appearance of equal volumes flowing at different velocities and of different volumes flowing at different velocities. In the initial series a solution of agitated hetasarch was used. When equal volumes were imaged at different velocities the higher-velocity jet appeared larger, both subjectively (3+ vs 1+) and by measuring the area encompassed in the Doppler flow profile (40.3 +/- 1.8 vs 22.0 +/- 1.4 cm2, p = 0.0001). Furthermore, when different volumes were imaged at different velocities, the smaller volume (3 ml vs 6 ml) appeared larger when it was flowing at higher velocity (3+ vs 2+, 40.3 +/- 1.8 vs 32.4 +/- 1.3 cm2, p = 0.0006). These experiments were repeated with blood, confirming the results of the initial study.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Flow Velocity↗

PubMed1998

Doppler echocardiography. II. Color Doppler imaging.

Color Doppler imaging (CDI) is a sophisticated form of ultrasound technology that overlays blood flow and velocity information onto a B-mode, two-dimensional, gray-scale image. This imaging technique--also called color Doppler echocardiography, color-coded Doppler, Doppler color-flow imaging, and color-flow imaging--is a type of pulsed-wave Doppler echocardiography. Because the anatomical site of received Doppler-shift information can be readily determined, CDI is useful for documenting normal blood flow patterns and screening the heart and great vessels for areas of abnormal flow.

Animals↗

PubMed1999

Doppler backscatter properties of a blood-mimicking fluid for Doppler performance assessment.

The Doppler backscatter properties of a blood-mimickig fluid (BMF) were studied to evaluate its suitability for use in a Doppler flow test object. Measurements were performed using a flow rig with C-flex tubing and BMF flow produced by a roller pump or a gear pump. A SciMed Doppler system was used to measure the backscattered Doppler power with a root-mean-square power meter connected to the audio output. Studies investigated the dependence of the backscattered Doppler power of the BMF with: circulation time; batch and operator preparations; storage; sieve size; flow speed; and pump type. A comparison was made with human red blood cells resuspended in saline. The backscatter properties are stable and within International Electrotechnical Commission requirements. The BMF is suitable for use in a test object for Doppler performance assessment.

Blood↗

PubMed1990

Doppler echocardiographic measurement of pulmonary artery pressure from ductal Doppler velocities in the newborn.

The ductal flow velocities in 37 newborns (group 1: persistent pulmonary hypertension [n = 16], transient tachypnea [n = 3], other [n = 2]; group 2: respiratory distress syndrome [n = 16]) were prospectively evaluated by Doppler ultrasound for the purpose of deriving systolic pulmonary artery pressures. Maximal tricuspid regurgitant Doppler velocity in 21 of these patients was used to validate the pulmonary artery pressures derived from ductal flow velocities. There was a significant linear correlation between tricuspid regurgitant Doppler velocity and pulmonary artery systolic pressure derived from ductal Doppler velocities in patients with unidirectional (pure left to right or pure right to left) ductal shunting (p less than 0.001, r = 0.95, SEE 8) and in those with bidirectional shunting (p less than 0.001, r = 0.95, SEE 4.5). Systolic pulmonary artery pressure in group 1 (67 +/- 13 mm Hg) was significantly higher than that in group 2 (39 +/- 10 mm Hg) (p less than 0.001). In those with bidirectional shunting, duration of right to left shunting less than 60% of systole was found when pulmonary artery pressure was systemic or less, whereas duration greater than or equal to 60% was associated with suprasystemic pulmonary artery pressures. Serial changes in pulmonary artery systolic pressure, reflected by changes in ductal Doppler velocities, correlated with clinical status in persistent pulmonary hypertension of the newborn. Persistently suprasystemic pulmonary artery pressure was associated with death in five group 1 patients. It is concluded that ductal Doppler velocities can be reliably utilized to monitor the course of pulmonary artery systolic pressures in newborns.

Blood Flow Velocity↗

PubMed1997

Utility of preload alteration in assessment of left ventricular filling pressure by Doppler echocardiography: a simultaneous catheterization and Doppler echocardiographic study.

OBJECTIVES: The aim of this study was to demonstrate the usefulness of preload alterations in assessing left ventricular filling pressures with transmitral Doppler velocity curves. BACKGROUND: Doppler mitral inflow velocities, used to estimate left ventricular filling pressures noninvasively, are limited in predicting left ventricular filling pressures, especially in patients with normal systolic function and a "pseudonormal" mitral filling pattern. METHODS: Forty-nine patients were studied in the cardiac catheterization laboratory with simultaneous Doppler echocardiography using high fidelity catheters to compare left ventricular diastolic filling pressures (pre-A wave left ventricular pressure) and Doppler mitral inflow at baseline and during reduction of preload during the strain phase of the Valsalva maneuver (n = 27) or sublingual nitroglycerin (n = 36), or both (n = 14). Doppler measurements consisted of E (initial peak velocity), A (velocity at atrial contraction), deceleration time (time from E velocity to deceleration of flow extrapolated to baseline) and absolute A wave velocity (A' [peak A wave velocity minus velocity at onset of atrial contraction]). RESULTS: In patients with high pre-A wave pressure (> or 15 mm Hg), there was a greater change in the E/A' ratio during the Valsalva maneuver than in patients with a normal pre-A wave pressure (-1.22 +/- 1.1 vs. -0.35 +/- 0.17; p = 0.02). A similar change was seen when comparing the change in the E/A' ratio after administration of nitroglycerin in patients with a high versus a normal pre-A wave pressure (0.81 +/- 0.49 vs. 0.18 +/- 0.17; p < 0.001). These differences were present in patients with a normal E/A ratio at baseline. CONCLUSIONS: Alterations in preload during assessment of Doppler echocardiographic indexes may be useful in noninvasively assessing left ventricular filling pressures.

Aged↗

PubMed1997

New semiautomated Doppler method for quantification of volumetric flow: intraoperative validation with multiplane transesophageal color Doppler imaging.

We have validated a new semiautomated method for quantification of volumetric flow applied to multiplane transesophageal color Doppler mapping. This Doppler technique assumes only the incompressibility of the fluid and includes variations of flow area. By computing velocity vectors across a surface normal to the point of scanning, volumetric flow can be measured independently of the angle of incidence between the ultrasonic beam and the direction of blood flow. Mitral valvular flow rate was measured during surgery by transesophageal color Doppler echocardiography in 27 patients undergoing coronary artery bypass grafting at 45 sets of observations. The results were compared with those obtained by the thermodilution technique. The mean of the differences between the thermodilution technique and color Doppler echocardiography was 0.06 +/- 0.866 L/min for the mitral valvular flows (mean of differences [thermodilution-color Doppler] &/- 2 SDs of differences). Thus mitral valvular volumetric flow measured by this color Doppler method showed a close agreement to the thermodilution technique during surgery.

Blood Flow Velocity↗

PubMed2002

[Normal values for the internal thoracic artery by Doppler ultrasound and modification of the Doppler curve after bypass to the left anterior descending artery].

AIM: In coronary heart disease, the surgical therapy of choice is the construction of an artenal bypass of the left anterior descending artery (LAD) using the internal thoracic artery 8ITA). We define age dependent normal values for the ITA such as diameter of the lumen (LD), peak systolic (Vs) and diastolic (Vd) flow velocity and the ratio of these two values (SDR) measured by duplex ultrasound. Furthermore, the modification and pathological changes of the Doppler curve after minimal invasive bypass of the LAD (MIDCAB) are described. MATERIAL AND METHODS: 96 people, age 18 - 87 years, subdivided into 6 age groups were examined by duplex to define the normal values of the ITA, and 55 patients (mean age 63 +/- 10 years, 48 men, 7 women) were evaluated after MIDCAB-surgery to describe the postoperative modification of the Doppler curve. The examinations were performed using a 4 - 7 MHz linear ultrasound transducer in the right and left 1. or 2. intercostal space parasternally. RESULTS: In all 96 people, the ITA was detectable on both sides presenting a typical bi- or triphasic Doppler flow profile. A linear age dependent increase in the LD of 1.95 +/- 0.15 mm (right ITA) and 1.93 +/- 0.27 mm (left ITA) respectively to 2.65 +/- 0.48 mm and 2.55 +/- 0.43 mm was found. No significant side difference was found for Vs and Vd, nor were there any age dependent differences for Vs. The SDR showed an age dependent linear increase on the right side from 3.5 +/- 1.1 to 6.1 +/- 2.2, p < 0.0012, and on the left from 3.9 +/- 1.2 to 6.7 +/- 1.7, p < 0.0001. Postoperatively, the Doppler spectrum was modified into a mono- or biphasic Doppler curve with a reduced Vs and an increased Vd resulting in a significantly decreased SDR on the left side compared with the right side (1.3 +/- 0.8 vs. 5.4 +/- 2.0, p < 0.00001). Three patients with angiographically proven graft failure had an SDR of 2.6 - 5.2 (mean 3.8), as opposed to a value of < 2.0 in case of a patent bypass. An SDR > 2.0 has a sensitivity of 100 % and a specificity of 97 % in the detection of a haemodynamically relevant (>70 %) ITA-graft-stenosis. CONCLUSIONS: With rising age, there is an increase in the LD of the ITA and the peripheral resistance, expressed as SDR. After MIDCAB surgery the former triphasic Doppler flow curve changes into a mono- or biphasic curve corresponding to the coronary blood flow. An SDR >2.0 is a strong indicator of bypass failure.

Adolescent↗

PubMed2001

Detection of early abnormalities of left ventricular function by hemodynamic, echo-tissue Doppler imaging, and mitral Doppler flow techniques in patients with coronary artery disease and normal ejection fraction.

We have investigated the possibility of detecting early abnormalities of left ventricular function at the initial phase of ischemic cardiomyopathy. Sixteen normotensive patients with coronary artery disease and normal left ventricular ejection fraction and 6 control patients were studied by invasive hemodynamic techniques in combination with transmitral Doppler flow or with echo-tissue Doppler imaging. The extent of the percentage of left ventricular longitudinal shortening and the systolic peak velocity at echo-tissue Doppler were significantly higher in the control patients than in patients with ischemic cardiomyopathy (P <.01). Left ventricular end-diastolic pressure was higher (P <.05), whereas mean values of isovolumic contraction and relaxation indexes (dP/dt/P: P <.05; +dP/dt: P <.05; -dP/dt: P <.01) were lower in patients with ischemic cardiomyopathy. Tau was significantly longer in ischemic patients (42.7 +/- 8.8 versus 34.5 +/- 3.7 ms, P <.05). In the control patients, the aortic valve closure to peak E interval by transmitral Doppler flow was significantly longer than that measured by echo-tissue Doppler (P <.001), whereas in patients with ischemic cardiomyopathy, this interval difference was still present and significantly shorter (P <.05). In patients with coronary artery disease and normal ejection fraction, minor and early abnormalities of left ventricular function related to isovolumic contraction and relaxation as well as to longitudinal shortening could be detected. In addition, a suction-like effect, detected during early filling evaluation with echo-tissue Doppler, is significantly decreased but not abolished during the early stages of coronary artery disease.

Adult↗

PubMed1991

Sensitivity and speed of colour Doppler flow mapping compared with continuous wave Doppler for the detection of ventricular septal defects.

Twenty nine patients (aged from three months to 37 years) with confirmed or suspected ventricular septal defects were studied separately by three examiners who used colour flow mapping and imaging, or continuous wave Doppler and imaging, or a combined reference examination. Colour flow mapping identified 19 of the 25 patients with a ventricular septal defect, continuous wave Doppler echocardiography identified 18, and the combined reference examination identified 24. Two of four patients without ventricular septal defect had a false positive result with colour flow mapping and none had a false positive result with continuous wave Doppler examination. During the reference examination continuous wave Doppler identified 24 patients with ventricular septal defects and colour flow mapping identified 23. In two patients a second ventricular septal defect was found by colour flow mapping, and confirmed by continuous wave Doppler. There was no significant difference in time to diagnosis between the two techniques. Colour flow mapping aids identification of multiple ventricular septal defects but is not faster and has lower specificity than continuous wave Doppler. A combination of the two techniques gave the highest sensitivity and specificity.

Adolescent↗