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At least 19 recordsLinked to original sources

Assessment of normal and abnormal prosthetic mitral valves by Doppler echocardiography. Doppler in prosthetic mitral valves.

Pulsed, continuous-wave, and color Doppler were performed in 165 normal mitral prostheses and 58 patients with prosthetic dysfunction (46 regurgitant and 12 obstructive valves) proved by catheterization and/or surgery. Mean mitral gradient (MG) and pressure half-time (PHT) were determined in all cases. Among normal prostheses, a wide range of both MG and PHT was observed in each type of valve and a considerable overlap between valves of different size. St-Jude's valve had the most optimal hemodynamics. Mild mitral insufficiency was detected in 14% of tissue and 24% of mechanical mitral valves. Repeat studies were performed in 30 patients over a 2.4 years period. Nine patients developed Doppler evidence of new prosthetic dysfunction, while Doppler parameters remained unchanged in 21 patients during the follow-up period. Among malfunctioning valves, Doppler correctly identified all cases of prosthetic obstruction (n = 12), and 42 of 46 regurgitant valves. We conclude that Doppler echocardiography is a very useful technique in both non-invasive assessment and follow-up of normal prosthetic valves in the mitral position and in detecting prosthetic dysfunction, especially when prosthetic obstruction is present.

Adolescent↗

[Analysis of mitral annulus excursion with tissue Doppler echocardiography (tissue Doppler echocardiography = TDE). Noninvasive assessment of left ventricular, diastolic dysfunction].

BACKGROUND: Mitral inflow velocity, deceleration time, and isovolumic relaxation time recorded by Doppler echocardiography have been widely used to evaluate left ventricular diastolic function but are affected by age, heart rate, loading conditions, and other factors. The diastolic mitral anulus velocity assessed by tissue Doppler echocardiography (TDE) was suggested to provide additional information about LV relaxation less affected by filling pressures. AIM OF THE STUDY: This study was designed to assess the clinical utility of mitral anulus velocity in the evaluation of left ventricular diastolic function. PATIENTS AND METHODS: Three groups of patients with a systolic ejection fraction > 45% were separated: 10 normal volunteers (60 +/- 10 y, CON group), 15 asymptomatic patients with known coronary artery disease (60 +/- 11 y, CAD group) and 15 patients with long-term arterial hypertension and heart failure symptoms (58 +/- 9 y, HYP group). The mitral inflow profile (E, A, E/A) was measured by pulsed Doppler, and the deceleration time (DT) and the isovolumic relaxation period (IVRT) were calculated. Systolic, early, and late diastolic velocities of the septal mitral anulus (ST, ET, AT, ET/AT) were assessed by pulsed TDE. All study subjects had invasive measurements of left ventricular end diastolic filling pressures during left heart catheterization. RESULTS: In the AH group, ET (6.9 +/- 4.8 cm/s) and ET/AT (0.71 +/- 0.28) were reduced compared to the CON group (11.7 +/- 4.7 cm/s and 1.11 +/- 0.36, p < 0.05, respectively) and the CAD group (8.9 +/- 5.4 cm/s and 0.85 +/- 0.26, respectively, p = ns). The groups did not differ with respect to the mitral E/A ratio, the deceleration time and the isovolumic relaxation time. LVED in the HYP group (16 +/- 8 mm Hg) was elevated compared to the CON group (8 +/- 3, p < 0.05) and the CAD group (12 +/- 6 mm Hg, p = ns). No correlation was found between ET and LVED (r = 0.26). When the combination of mitral E/A ratio > 1 with LVED > or = 15 mm Hg was classified as pseudonormalization, the pseudonormalization could be identified by a peak early diastolic mitral anulus velocity (ET) < 7 cm/s and an ET/AT ratio < 1 with a sensitivity of 77% and a specificity of 88%. CONCLUSIONS: The early diastolic mitral anulus velocity assessed by TDE (ET) is a preload-independent index of LV relaxation. TDE permits the detection of diastolic dysfunction in patients with a pseudonormal mitral inflow and elevated filling pressures.

Adult↗

[Assessment of left internal thoracic artery graft by exercise Doppler echocardiography].

Doppler echocardiography has several advantages such as frequent use, noninvasive approach, and physiological evaluation. Supine bicycle exercise testing was conducted for 30 patients undergoing CABG with LITA to LAD. Doppler echocardiography studies were performed before and after exercise to observe the change. On the basis of the angiographic data, patients were divided into two groups: 27 patients with a patent LITA graft, 3 patients with mildly stenosed LITA graft. In the patients who had patent grafts, diastolic flow velocity were increased higher than systolic after exercise. In the stenotic group, the flow pattern was changed to further systolic one. Doppler echocardiography during exercise is thought to be a reliable method to assess the LITA flow.

Adult↗

Evaluation of left-sided valvular regurgitation in healthy, hypertensive and myocardial infarction subjects by Doppler echocardiography.

Doppler echocardiography has become a very useful and widely employed imaging technique for evaluating valvular regurgitation, and has thus lead to the discovery of regurgitation in unexpected subjects. In this study, we examined left-sided valvular regurgitation in 31 healthy subjects, 35 patients with hypertension and 43 patients with old myocardial infarction by Doppler echocardiography. Aortic regurgitation was found in 3% of healthy subjects, 8% of hypertensive patients and 5% of patients with myocardial infarction. Mitral regurgitation was found in 35% of healthy subjects, 69% of hypertensive patients and 84% of patients with myocardial infarction. The pathogenesis of mitral regurgitation in hypertension is considered to be the impairment of the mitral leaflets, since neither anatomical nor functional abnormalities were found in the subvalvular mitral apparatus. Left ventricular dilatation and asynergy near the papillary muscles were related to the pathogenesis of mitral regurgitation in myocardial infarction. Mitral regurgitation in healthy subjects and hypertensive patients was mild and resistant to afterload stress, suggesting that it was less pathological. On the other hand, mitral regurgitation in myocardial infarction was easily worsened by afterload stress. Doppler echocardiography has thus provided us with new insights into valvular regurgitation in healthy subjects and patients without rheumatic valvular disease.

Adult↗

Evaluation of ventricular function using Doppler echocardiography.

Doppler echocardiography is closely related to M mode and two dimensional echocardiography, although it uses reflected ultrasonic signals to examine blood flow rather than to image cardiac anatomy. It is a useful adjunct to standard echocardiographic methods when one wishes to evaluate ventricular function, but at present it plays a supporting role. In theory, Doppler techniques can be used to assess global ventricular function directly and without regard to ventricular geometry, to calculate volume flow from both the right and left ventricles, and to follow changes in ventricular stroke volume induced by interventions. In practice, various technical limitations restrict the routine clinical application of Doppler echocardiography, but solutions to several of these problems should be forthcoming. Doppler echocardiography can properly be viewed as a useful method for evaluating mechanical lesions that may mimic ventricular dysfunction, and as a promising future method for analyzing ventricular function directly.

Aortic Valve Insufficiency↗

Frequency of mitral valve dysfunction from mitral anular calcium as detected by Doppler echocardiography.

Doppler echocardiography is useful for detecting and quantifying mitral regurgitation (MR) and mitral stenosis (MS). To determine the prevalence of these abnormalities in patients with mitral anular calcium (MAC), 51 consecutive patients who had an echocardiographic diagnosis of MAC were examined by Doppler ultrasound. Transmitral flow was evaluated to determine the presence of MR or left ventricular inflow obstruction (MS) by continuous and pulsed-wave Doppler echocardiography. The severity of these hemodynamic abnormalities was quantitated by previously described techniques. Eleven patients (22%) had mild MR, 17 (33%) had moderate to severe MR and 4 (8%) had significant MS. Clinical findings such as a systolic murmur, evidence of congestive heart failure, and dyspnea on exertion were not helpful in distinguishing patients with no or mild MR from those who had moderate to severe MR. M-mode measured left atrial size was significantly larger (p less than 0.05) in patients with moderate to severe MR. This study suggests that MR is often associated with MAC, that MS is not a rare finding with MAC, and that Doppler echocardiography can quantitate these lesions in the elderly when symptoms are not specific and physical findings are inconclusive or absent.

Aged↗

Effects of balloon valvuloplasty on left anterior descending coronary artery blood flow in a neonate with critical aortic stenosis with transthoracic doppler echocardiography.

Doppler echocardiography has recently been used in the assessment of coronary flow dynamics. We described the application of transthoracic Doppler echocardiography for the measurement of the coronary flow before and after balloon valvuloplasty in a neonate with critical aortic stenosis. In this case, coronary flow volume/left ventricular mass ratio increased after the procedure, suggesting the improvement of myocardial blood perfusion. Thus, this technique may provide additional information about coronary flow dynamics in patients with critical aortic stenosis.

Aortic Valve Stenosis↗

Normal and abnormal prosthetic valve function as assessed by Doppler echocardiography.

Doppler echocardiography was performed in 136 patients with a normally functioning prosthetic valve in the aortic (n = 59), mitral (n = 74) and tricuspid (n = 3) positions. These included patients with St. Jude (n = 82), Björk-Shiley (n = 18), Beall (n = 13), Starr-Edwards (n = 7) or tissue (n = 16) valves. Peak and mean pressure gradients across the prostheses were measured using the simplified Bernoulli equation. The prosthetic valve orifice (PVO, in square centimeters), only in the mitral position, was calculated by the equation: PVO = 220/pressure half-time. In the aortic position, the St. Jude valve had a lower peak velocity (2.3 +/- 0.6 m/s, range 1.0 to 3.9), peak gradient (22 +/- 12 mm Hg, range 4 to 61) and mean gradient (12 +/- 7 mm Hg, range 2 to 32) than the other valves (p less than 0.05) when compared with Starr-Edwards). In the mitral position, the St. Jude valve had the largest orifice (3.0 +/- 0.6 cm2, range 1.8 to 5.0) (p less than 0.0001 compared with all other valves). Insignificant regurgitation was commonly found by pulsed mode Doppler technique in patients with a St. Jude or Björk-Shiley valve in the aortic or mitral position and in patients with a Starr-Edwards or tissue valve in the aortic position. In 17 other patients with a malfunctioning prosthesis (four St. Jude, two Björk-Shiley, four Beall and seven tissue valves) proven by cardiac catheterization, surgery or autopsy, Doppler echocardiography correctly identified the complication (significant regurgitation or obstruction) in all but 2 patients who had a Beall valve. It is concluded that 1) the St. Jude valve appears to have the most optimal hemodynamics; mild regurgitation can be detected by the Doppler technique in normally functioning St. Jude and Björk-Shiley valves in the aortic or mitral position and in Starr-Edwards and tissue valves in the aortic position, and 2) Doppler echocardiography is a useful method for the detection of prosthetic valve malfunction, especially when the St. Jude, Björk-Shiley and tissue valves are assessed.

Adolescent↗

A simple noninvasive measurement of stenotic mitral valve area: an alternative approach using M-mode and Doppler echocardiography.

Doppler echocardiography is a widely used noninvasive technique to examine the mitral valve area (MVA) by obtaining mitral pressure half-time (PHT) and to assess the severity of the stenosis. However, several hemodynamic factors influence the PHT and may render the PHT data inaccurate in any measurement of MVA under certain conditions. Using a simple echo-Doppler (E-D) method, we assessed the MVA in a physiological equation. The mitral flow volume (MFV) is represented by MVA x transmitral mean flow velocity (mV) x diastolic filling time (DFT). Thus, the formula can be restated as MVA (cm2) = MFV (cm3)/mV (cm/sec) x DFT (sec). We measured MFV by M-mode, and mV and DFT by continuous wave Doppler echocardiography. This formula was tested in 43 patients with isolated mitral stenosis. MVA was obtained by the PHT and E-D methods, and the data obtained were validated against the results of cardiac catheterization. The results obtained using the E-D method showed much better correlation (r = 0.82) with those of catheterization than those with the PHT method (r = 0.52). The inter- and intraobserver variabilities were checked. The results obtained with the E-D method were found to be reproducible. To further validate the accuracy of the E-D method, MVA was measured by both methods at different R-R intervals after exercise and the results were compared. The MVA obtained by the PHT method showed marked variations; whereas, that obtained by the E-D method remained nearly constant. Similarly, in a patient with atrial fibrillation, the MVA assessed by the PHT method varied from beat to beat; whereas, the fluctuations in MVA were minimal using the E-D method. We concluded that the E-D method can be reliable and clinically easily applicable for the accurate assessment of MVA.

Adult↗

[How to assess dysfunction of the left ventricle after myocardial infarction with Doppler echocardiography].

Doppler echocardiography is one of the most useful non-invasive methods of cardiac imaging in patients who have suffered myocardial infarction because it provides important information such as the immediate identification of the infarct, its size, possible mechanical complications and an assessment of its effects on global ventricular function, all in a single procedure. Several mathematical formulae have been proposed to quantify global left ventricular function from two-dimensional imaging; the most commonly used are the surface-length method based on the parasternal short axis view (V = 5/6 A.L) and reconstruction by Simpson's method based on two orthogonal apical views. Hemodynamic data may be obtained by Doppler studies, especially of the ejection phase (transaortic velocities and cardiac output determination) and left ventricular filling. The effects of left ventricular dysfunction on the right heart may be evaluated when tricuspid regurgitation is present as right ventricular and pulmonary artery systolic pressures can be determined. The non-invasive nature of Doppler echocardiography enables documentation of these parameters of ventricular function as often as the patient's clinical status requires during follow-up, or to assess the effects of treatment in the post-infarction period.

Echocardiography, Doppler↗

Hemodynamic progression of aortic stenosis in adults assessed by Doppler echocardiography.

Doppler echocardiography was used to follow the hemodynamic severity of aortic stenosis. First, the reproducibility of repeat recordings (mean interval 28 +/- 36 days) of aortic jet velocity, made by two independent observers, was tested in 38 adults with aortic stenosis and unchanged clinical status. The two recordings of maximal velocity correlated well (r = 0.96, y = 0.88x + 0.46m/s, SEE = 0.21 m/s) with a mean coefficient of variation of 3.2%. Repeat recording of left ventricular outflow tract velocity by two independent observers in 10 other patients with aortic stenosis also correlated well (r = 0.94, y = 1.06x + 0.0 m/s, SEE = 0.06 m/s) with a mean coefficient of variation of 4.6%. Next, Doppler echocardiography was used to study 42 patients with aortic stenosis (mean age 66 years) over a follow-up interval of 6 to 43 months (mean 20). Maximal aortic jet velocity increased by 0.36 m/s per year (range -0.3 to +1.0 m/s per year). Mean transaortic pressure gradient changed by -7 to +23 (mean 8) mm Hg/year. Aortic valve area by the continuity equation (n = 25) decreased by 0 to 0.5 cm2/year (mean decrease 0.1 cm2/year). Some patients had a worsening of stenosis (decrease in valve area) even though they had no change or a decrease in pressure gradient, because of concurrent decreases in transaortic volume flow. Twenty-one patients (50%) developed new or progressive symptoms of aortic stenosis necessitating valve replacement.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Detection of aortic insufficiency by standard echocardiography, pulsed Doppler echocardiography, and auscultation. A comparison of accuracies.

To determine the relative sensitivity and specificity of noninvasive methods for detecting aortic insufficiency, we compared the accuracy of auscultation, echocardiography, and pulsed Doppler echocardiography in detecting aortic insufficiency in 106 patients in whom the presence or absence of the lesion was shown by supravalvular aortography. The sensitivity and specificity for the diagnosis of aortic regurgitation was 96% and 96% for pulsed Doppler echocardiography, 73% and 92% for auscultation, 43% and 91% for two-dimensional echocardiography, 46% and 81% for anterior mitral leaflet flutter, and 9% and 96% for ventricular septal flutter, respectively. Auscultation was more sensitive than either M-mode or two-dimensional echocardiography in the diagnosis of aortic insufficiency (p less than 0.01). Pulsed Doppler echocardiography was significantly more sensitive than auscultation (p less than 0.0001) and was positive in 19 patients in whom no murmur was found. Thus, pulsed Doppler echocardiography is the optimal noninvasive marker for aortic insufficiency.

Adolescent↗

Gabor spectra for Doppler echocardiography.

Doppler echocardiography on current ultrasonography machines makes use of short-time Fourier spectrograms (STFTs) to display the patterns of blood velocities in the heart chamber. From these sonologists infer the functional parameters, such as valve area, that have pathological significance. After mention of the lacuna in such an STFT display, the Gabor transform and associated Gabor spectrogram evaluation techniques are described. Finally, comparative views of ultrasound machine display with PC-based STFT and Gabor displays for two typical patients are shown, with inferences in support of the proposed Gabor display.

Blood Flow Velocity↗

Validation and applications of mitral prosthetic valvular areas calculated by Doppler echocardiography.

Doppler echocardiography is used in the noninvasive evaluation of mitral valve prostheses using parameters heretofore validated primarily for native valves. Accordingly, this study was designed to examine the validity and relative usefulness of valve gradient and area measurements in a group of 26 patients (17 women, 9 men, mean age 62 +/- 8 years), 19 +/- 4 months after implantation of different sizes (25 to 31 mm) of a given type of bioprosthesis. Areas obtained with both the continuity equation, using stroke volume measured in the left ventricular outflow tract, and the pressure half-time method are compared to known prosthetic areas derived from an in vitro hydraulic model. Areas calculated by the continuity equation correlate well with in vitro areas (r = 0.82, standard error of the y estimate = 0.1 cm2, p less than 0.001), and are within the range of predicted in vitro values in 92% of cases. Areas derived by the pressure half-time method do not correlate with in vitro areas (r = 0.15, p greater than 0.3) or continuity equation areas (r = 0.23, p greater than 0.2), and are above the range of predicted values in 69% of cases. Correlations are also found between continuity equation areas and the peak and mean valvular gradients (r = 0.59, p less than 0.005 and r = -0.63, p less than 0.0005, respectively). Taking the effect of cardiac output on gradients into account results in projected relations between indexed prosthetic areas and the pressure gradients at rest and during exercise.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

A case of right atrial myxoma--effect of large myxoma in the right atrium studied by M-mode and Doppler echocardiography.

Doppler profiles are rarely used to assess cardiac function that has been partially impaired by a sizeable myxoma in the right atrium or to evaluate the improvement caused by extirpation of the tumor. In a 54-year-old man with a large right atrial myxoma (6.5 x 5.5 x 4.0 cm) along with first-degree atrioventricular (AV) block, M-mode and pulsed Doppler echocardiography were used to evaluate the left ventricular systolic and diastolic function before and 1 month after surgical removal of the myxoma. End-diastolic left ventricular (LV) and left atrial diameters increased postsurgically from 47 to 51 mm and from 38 to 41 mm, respectively, while end-systolic LV remained unchanged. In the LV inflow pattern, peak early filling velocity (E) increased substantially (preoperative 31, postoperative 58 cm/sec), with no change in peak late filling velocity (A) (53 cm/sec), which gave a favorable E/A ratio (from 0.58 to 1.09). First-degree AV block resolved after tumor resection (PR interval: 0.23 vs 0.20 sec). Improved LV diastolic function associated with natural recovery from the myxoma was ascribed to the restoration of preload and recovery of systolic function. The results of this study show that removal of a large myxoma in the right atrium is important not only for preventing possible obstruction of the tricuspid orifice, eliminating pulmonary emboli, and maintaining systolic function, but also for restoring LV diastolic function.

Diastole↗

Assessment of diastolic dysfunction after acute myocardial infarction using Doppler echocardiography.

Doppler echocardiography (DE) is becoming a powerful noninvasive tool for assessing left ventricular diastolic dysfunction after myocardial infarction (MI). Transmitral inflow DE measurements of early and late filling velocities, early to late ratio and early deceleration time correlate well with left ventricular filling pressure. Three abnormal filling patterns (impaired relaxation, pseudonormalization and restrictive) develop after MI, depending on infarct size. Pulmonary venous inflow DE contributes important additional diagnostic data and, when combined with transmitral DE, avoids potential confusion due to the pseudonormal pattern that develops in the presence of high left atrial pressure and impaired relaxation. Several studies indicate that these DE patterns correlate with progressively increasing functional impairment, and the restrictive transmitral pattern predicts heart failure and death among MI survivors. Further studies are needed to evaluate the effects of therapy on the DE patterns of diastolic dysfunction after MI.

Diastole↗

Assessment of valvular heart disease by Doppler echocardiography.

Doppler echocardiography provides direct hemodynamic data that are often complementary to those demonstrated by M-mode and two-dimensional echocardiographic imaging. This relatively new noninvasive technique has a number of important uses in patients with valvular heart disease. In both adults and children, Doppler measures of peak flow velocity through a stenotic valve allow accurate prediction of the pressure gradient across the valve, and the technique has particular promise for screening patients with suspected aortic or pulmonic stenosis. In patients with mitral stenosis but parasternal short-axis images of limited quality, Doppler velocity measures can provide novel data about the pressure gradient and mitral orifice area. Doppler techniques can also provide direct evidence for or against the presence of valvular regurgitation, and several approaches allow clinically useful estimation of the extent of aortic, mitral, or tricuspid regurgitation. In patients with known disease of one cardiac valve, Doppler is accurate for evaluating the integrity of a second valve. Finally, Doppler techniques have great promise for defining the nature, and perhaps the severity, of suspected prosthetic valve malfunction. Hence, we believe that Doppler echocardiography should become a routine part of the noninvasive evaluation of patients with known or suspected valvular heart disease.

Aortic Valve Insufficiency↗

Automatic Border Detection for Assessment of Left Ventricular Diastolic Function Among Normal Neonates: Comparison with Doppler Echocardiography.

Doppler echocardiography is the standard noninvasive method to assess left ventricular (LV) diastolic function. Recently, automatic border detection (ABD), a method based on analysis of integrated ultrasonic backscatter, has been introduced permitting real-time, on-line assessment of LV diastolic function. A comparison of these methods in normal, full-term neonates has not been performed. Therefore, the objectives of this study were to evaluate the usefulness of ABD in the assessment of LV diastolic function among normal neonates, to compare parameters obtained with the ABD method with standard Doppler-derived indexes of diastolic function, and to assess the reproducibility of ABD measurements. We studied 17 consecutive normal neonates during natural sleep with both methods shortly after birth (mean 17.4 +/- 3.9 h) and approximately 2 weeks later (mean 14.8 +/- 2.2 days). An average of five consecutive cardiac cycles were performed. Similar to Doppler indexes, no significant change in any ABD parameter of diastolic function occurred between the early and later studies. A complete ABD study could be performed within 5 minutes. Mean interobserver variation for individual ABD measurements ranged from 0% to 11%. Compared with Doppler, rapid filling fraction was greater and atrial filling fraction was less with ABD. Regression analysis showed poor correlation of these parameters between methods, but their ratio by each method remained constant between studies. A similar poor correlation existed between peak E wave velocity by Doppler and peak rapid filling rate by ABD and between peak A wave velocity by Doppler and peak atrial filling rate by ABD. These differences may be explained by technical factors and different aspects of diastolic filling assessed by each method. This study indicated that ABD was a feasible and reproducible method compared with Doppler echocardiography for serial evaluation of LV diastolic function among neonates.

Journal Article↗