Color M-mode Doppler Flow Propagation Research Articles

Value of dual Doppler echocardiography for prediction of atrial fibrillation recurrence after radiofrequency catheter ablation

BackgroundIncreasing evidence has been presented which suggests that left ventricular (LV) diastolic dysfunction may play an important role in the development of atrial fibrillation (AF). However, the potential for LV diastolic dysfunction to serve as a predictor of AF recurrence after radiofrequency catheter ablation remains unresolved.MethodsDual Doppler and M-PW mode echocardiography were performed in 67 patients with AF before ablation and 47 patients with sinus rhythm. The parameters measured within identical cardiac cycles included, the time interval between the onset of early transmitral flow peak velocity (E) and that of early diastolic mitral annular velocity (e’) (TE-e’), the ratio of E to color M-mode Doppler flow propagation velocity (Vp)(E/Vp), the Tei index, the ratio of E and mitral annular septal (S) peak velocity in early diastolic E/e’(S) and the ratio of E and mitral annular lateral (L) peak velocity E/e’(L). A follow-up examination was performed 1 year after ablation and patients were divided into two groups based on the presence or absence of AF recurrence. Risk estimations for AF recurrence were performed using univariate and multivariate logistic regression.ResultsTE-e’, E/Vp, the Tei index, E/e’(S) and E/e’(L) were all increased in AF patients as compared with the control group (p < 0.05). At the one-year follow-up examination, a recurrence of AF was observed in 21/67 (31.34%) patients. TE-e’ and the Tei index within the recurrence group were significantly increased as compared to the group without recurrence (p < 0.001). Results from multivariate analysis revealed that TE-e’ can provide an independent predictor for AF recurrence (p = 0.001).ConclusionsDual Doppler echocardiography can provide an effective and accurate technique for evaluating LV diastolic function within AF patients. The TE-e’ obtained within identical cardiac cycles can serve as an independent predictor for the recurrence of AF as determined at 1 year after ablation.

Analysis of dual-Doppler simultaneous technique and asynchronous technique in assessing left ventricular diastolic function in patients with atrial fibrillation

Objective To evaluate the value of dual-Doppler imaging technology (referred to as dual-Doppler modality for short) in assessing left ventricular diastolic function in patients with atrial fibrillation (AF) and normal left ventricular ejection fraction (LVEF). Methods A total of 40 patients with AF and normal LVEF were enrolled as the AF group, and 40 healthy volunteers were composed of the control group. ①Peak early diastolic transmitral flow velocity (E) and tissue Doppler lateral (L) mitral annular early diastolic velocity (e′) were measured simultaneously in the particular cardiac cycle by dual-Doppler modality. ②Peak early diastolic transmitral flow velocity (E) and tissue Doppler septal (S) mitral annular early diastolic velocity (e′) were measured simultaneously in the particular cardiac cycle. ③Peak early diastolic transmitral flow velocity (E) and color M-mode Doppler flow propagation velocity (Vp) were measured simultaneously in the particular cardiac cycle. Then E/e′(L), E/e′(S) and E/Vp were calculated, respectively. Results Compared to the control group, E/e′(L), E/ e′(S)and E/Vp were all higher in AF group (P<0.05). Bland-Altman showed that E/e′(L), E/ e′(S)and E/Vp measured by the dual-Doppler modality had better reproducibility and higher intraclass correlation coefficient (ICC) than the conventional Doppler modality. Conclusions The dual-Doppler modality is valuable for evaluating left ventricular diastolic function in patients with AF and has better reproducibility and more accurate results than the conventional Doppler modality. Key words: Echocardiography, Doppler; Atrial fibrillation; Ventricular function, left; Dual-Doppler technology

Accuracy of Noninvasive Estimation of Pulmonary Wedge Pressure by Echocardiographic Indices in Heart Transplant Recipients

BackgroundPulmonary capillary wedge pressure (PCWP) can be estimated from transmitral or color M-mode Doppler flow propagation velocities. However, it has been recommended to not use these indices in heart transplant recipients. Our aim was to compare the accuracy of color M-mode, Doppler, and Doppler tissue imaging (DTI)–derived indices to predict PCWP in heart transplant recipients. MethodsWe studied 50 consecutive heart transplant recipients scheduled for routine right-sided heart catheterization and endomyocardial biopsy. Their mean age was 49 ± 17 years and the mean time after heart transplantation was 29 ± 41 months. An echocardiogram was performed immediately after the invasive procedure. We analysed PCWP, transmitral flow velocity variables (peak velocity during early filling (E) and deceleration time [DT]), color M-mode Doppler flow propagation velocity (Vp), and mitral annulus peak early diastolic velocity (E′) from DTI. Doppler estimated-PCWP (ePCWP) was calculated as follows: (5.27 × E/Vp) + 4.6. ResultsMean ejection fraction was 66 ± 11%. The mean invasive measured PCWP was 11.14 ± 5.4 mm Hg and the mean noninvasive ePCWP was 11.13 ± 1.8 mm Hg (r = 0.66; P < .0001). A good correlation was present between invasive PCWP and mitral PW-Doppler and DTI parameters: peak E 91 ± 22 cm/s (r = 0.34; P = .02) and DT 143 ± 26 s (r = −0.436; P = .002), E/E′ ratio medial mitral annulus 10 ± 4 cm/s (r = 0.353; P = .026) and E/E′ ratio lateral mitral annulus 6 ± 2 cm/s (r = 0.462; P = .002). E/Vp was the most accurate index for predicting PCWP (r = 0.615; P < .0001). ConclusionsCompared with other indirect Doppler indices, E/Vp showed the best correlation to predict PCWP in heart transplant recipients. Despite previous recommendations, PCWP can be accurately estimated from color M-mode indices, giving useful information and avoiding the risks of invasive measurements.

Assessment of left ventricular diastolic function after mitral valve replacement using color M-mode Doppler flow propagation velocity

Objective To evaluate the clinical value of color M-mode Doppler echocardiography (CMM) in assessing left ventricular(LV) diastolic function after mitral valve replacement(MVR). Methods Fifty-two patients who had received the implantation for more than three months were examined by echoeardiography (MVR group). Thirty age and sex-adjusted normal volunteers served as control group. Dimensions of left atrium and ventricle,ejection fraction(EF) and mitral inflow velocity(E) were measured by two-dimensional and Doppler eehocardiography. Color M-mode Doppler flow propagation velocity(Vp) and TDl-derived diastolic mitral annular velocity(Em) were measured from the apical four-chamber and two-chamber views. Then two new indexes based on the ratio of E to Vp(E/Vp) and E to Era' (E/Em') were while E/Vp and E/Era' increased, there were significant differences(P 0.05). dysfunction were 2.00. Conclusions CMM is an effective technique to assess LV diastolic function after MVR. E/Vp has good consistency with E/Era and may be a potential useful parameter for assessing LV diastolic function. Key words: Echocardiography; Heart valve prosthesis implantation; Ventricular function,left

Echocardiographic Doppler Evaluation of Ventricular Function in Children With an Atrial Septal Defect

To evaluate ventricular function using Doppler echocardiography in patients with an atrial septal defect (ASD). The study involved 158 children, who were divided into two groups: Group 1 comprised 111 children with an ASD, and Group 2, 47 healthy children. Left ventricular systolic function was evaluated by measuring the ejection fraction, the shortening fraction, and the systolic mitral annular velocity (by tissue Doppler), and right ventricular systolic function, by measuring the systolic tricuspid annular velocity. Left ventricular diastolic function was evaluated by measuring standard transmitral Doppler indices, the color M-mode Doppler flow propagation velocity (Vp), the E/Vp ratio, and early and late diastolic mitral annular velocities at the lateral and septal areas of the mitral annulus (EML, EMS and AML, AML waves, respectively), and right ventricular diastolic function, by using pulsed tissue Doppler to measure early and late diastolic tricuspid annular velocities (ET and AT waves, respectively). There was no significant difference between the two groups in any left ventricular systolic or diastolic function parameter, except that the EML and EMS velocities were smaller in Group 1. Right ventricular systolic function was significantly increased in children with an ASD. The peak ET wave velocity was similar in the two groups but the peak AT wave velocity was significantly greater in children with an ASD. Systolic and diastolic left ventricular function (i.e., preload-independent indices) were similar in the two groups. Children with an ASD demonstrated an increase in right ventricular systolic function, though diastolic function was unchanged.

Intraventricular Pressure Gradients in Left Ventricular Aneurysms Determined by Color M-Mode Doppler Method: An Animal Study

Left ventricular aneurysm (LVA) may affect diastolic intraventricular blood flow. Color M-mode (CMM) Doppler flow propagation patterns are abnormal in the presence of apical aneurysms. The aim of this study was to validate the accuracy of CMM echocardiography for assessing the existence and size of LVA and to determine the intraventricular pressure gradient in LVA. CMM of the transmitral inflow in early diastole was obtained from the apical 4-chamber view in 19 sheep. The presence of the break point where the velocity decreased abruptly in the mitral inflow (point D) was determined and the distance between the apex and point D was measured. The intraventricular pressure difference between the base and the apex was measured by a catheter while it was calculated using CMM with the Euler equation. The presence of the break point D showed 84% sensitivity and 100% specificity for determining the existence of an LVA. Distance between the apex and point D correlated well with scar size. Catheter- and CMM-derived intraventricular pressure difference correlated and agreed well (y = 1.0 x -0.2, r = 0.94). The point of abrupt decrease in propagation velocity of the CMM recording indicated the presence and size of LVA. Intraventricular pressure gradients were determined noninvasively by CMM echocardiography with reasonable accuracy.

Late Left Ventricular Color M-Mode Doppler in the Assessment of Diastolic Dysfunction in Patients with Dilated Cardiomyopathy

The ratio of early (Ep) to late (Ap) color M-mode Doppler flow propagation through the left ventricle helps in the differentiation between normal and pseudonormal (PSN) filling pattern in patients with preserved systolic function. We studied the value of this index in the assessment of diastolic dysfunction for patients with reduced left ventricular systolic function. We studied 80 patients with nonischemic dilated cardiomyopathy and 50 control subjects. According to echocardiography 53 patients had abnormal relaxation and 27 had PSN pattern. Patients had reduced Ep (P < .001) and Ep/Ap ratio (P < .001) and increased Ap (P = .001) compared to controls. Binary logistic regression analysis showed that Ep followed by Ep/Ap ratio (both P < .001) were the best determinants for the discrimination of PSN from normal filling pattern. Ep/Ap ratio, this novel echo-index, increases the diagnostic accuracy of color M-mode Doppler in discriminating normal from PSN filling pattern in patients with left ventricular systolic dysfunction.

Evaluation of Left Ventricular Function in Cardiomyopathic Mice by Tissue Doppler and Color M‐Mode Doppler Echocardiography

Tissue Doppler imaging (TDI) and color M-mode Doppler flow propagation velocity (Vp) are used to assess cardiac function in humans, but the feasibility and applicability of these measurements to murine cardiomyopathic models of heart failure remain unclear. Left ventricular (LV) function was measured by TDI and Vp among mice exhibiting severe dilated cardiomyopathy (TOT), pressure-overload hypertrophy (TAC), and normal controls (NTG). Transmitral flow pattern in TACs and TOTs showed a restrictive filling pattern, but early diastolic mitral annulus velocity was comparable among the three studied groups. Propagation velocity in an anesthetized state was comparable in all three groups. However, while Vp increased in all three groups in the conscious state, the increase in NTGs was statistically greater than in TACs and TOTs. Collectively, results indicate that color M-mode Doppler echocardiography can be used to assess LV function in mice. Furthermore, Vp is depressed by anesthesia, a complication that can lead to misinterpretation of LV function in normal hearts.

Mitral valve leaflet excursion velocity in the pediatric population: A comparable diastolic index to the color M-mode propagation velocity

Color M-mode (CMM) Doppler flow propagation velocity (Vp) is a reliable diastolic index, but may be difficult to define. We hypothesized that because the valve is opened by flow, the anterior mitral leaflet excursion velocity (MEVApex ), interrogated from the cardiac apex, may be similar to the CMM-Vp. We investigated the MEVApex by apical M-mode echocardiography in 49 children and adolescents with normal echocardiograms, and compared it with the CMM-Vp and other indices. The mean CMM-Vp and MEVApex were similar (41.5 +/- 6 vs 40 +/- 5.7, respectively, mean +/- SD; P = .5) and correlated positively ( r = 0.71, P < .0001, Bland-Altman analysis). The peak velocity of mitral inflow (E wave) divided by the Vp (E/Vp) and E/MEVApex correlated well (2.54 +/- 0.58 vs 2.52 +/- 0.58, respectively, mean +/- SD; r = 0.857, P < .001, Bland-Altman analysis). The MEVApex is comparable with the CMM-Vp and the E/MEVApex with E/Vp. The Vp may be assessed either by CMM or conventional M-mode from the apex. In our experience, the latter is easier to do. Study in other populations is warranted.

1016-156 Color M-mode Doppler flow propagation velocity is a new echocardiographic method for quantification of mitral regurgitation

1016-156 Color M-mode Doppler flow propagation velocity is a new echocardiographic method for quantification of mitral regurgitation

Late left ventricular diastolic flow propagation velocity determined by color M-mode Doppler in the assessment of diastolic dysfunction

Background Early color M-mode Doppler flow propagation (Ep) through the left ventricle (LV) has been proposed as a useful noninvasive index for assessing LV relaxation, whereas data concerning late velocity propagation (Ap) is lacking. Methods We studied 51 patients with delayed relaxation (group I) and 50 with pseudonormal filling pattern (group II). Another 51 aged-matched healthy persons served as the control group. Results Patients showed increased left atrial dimensions, atrial wave of the pulmonary vein flow, and Ap, and reduced LV ejection fraction, Ep, and Ep/Ap ratio compared with the control group. Patients in group II revealed increased left atrial dimensions ( P = .001), atrial wave of the pulmonary vein flow ( P < .001), and Ep/Ap ratio ( P < .001), and reduced LV ejection fraction and Ap ( P < .001) compared with group I. Regression analysis showed that the strongest independent variable distinguishing normal from pseudonormal filling pattern was the Ep/Ap ratio. Conclusion Ap evaluation offers a new diagnostic diastolic index, especially in the field of the pseudonormal pattern where the separation from normal is difficult.

The Usefulness of Color M-mode Doppler Echocardiographic Indices in the Assessment of Left Ventricular Diastolic Function

Background and Objectives:Early color M-mode Doppler flow propagation (Vp) has been used to distinguish pseudonormal from normal diastolic filling patterns. However, the role of other indices, including the late dia- stolic propagation velocity (Ap) and time delay of mitral flow propagation (VpTD and ApTD), is not clear. Subjects and Methods:Doppler echocardiographic examinations were performed in 89 patients (60.6±9.9 ye- ars, male 59.6%), with an ejection fraction ≥40%, who were admitted for diagnostic coronary angiography. The clinical diagnoses on admission were stable angina (41.6%), unstable angina (30.3%), old myocardial infarction (24.7%) and atypical chest pain (3.3%). The diastolic filling patterns, as confirmed by mitral inflow and pulmo- nary venous flow, were compared with the Ap, VpTD and ApTD indices using color M-mode Doppler echo- cardiography. Results:The age, left ventricular ejection fraction, left ventricular end diastolic and end systolic dimensions, the left atrial size, and the E' and A' velocities of the mitral annulus tissue Doppler were signifi- cantly different between patients with normal and abnormal diastolic filling patterns. In patients with normal filling, impaired relaxation and pseudonormalized filling patterns, the VpTD were 63.1±14.9, 85.2±25.5 and 107.8±36.8 ms (p<0.001), the E/Vp were 1.3±0.4, 1.6±0.6 and 3.1±0.7 (p<0.001), and the E/VpTD were 1.2±0.5, 0.7±0.2 and 0.9±0.4 (p<0.001), respectively. The Ap and ApTD showed significant differences between patients with normal and pseudonormalized filling patterns (Ap 58.3±23.5 vs. 36.2±15.1, p=0.000; ApTD 47.1±19.5 vs. 66.7±22.2, p=0.001). The PVa duration, an index that depends on the left ventricular end-diastolic pressure, was the most important independent predictor for ApTD from a multiple regression analysis (R2 =71.4%). Conclusion: The color M-mode Doppler indices, Ap, VpTD and ApTD, are new diagnostic parameters for diastolic dys-

Color m-mode and doppler tissue evaluation of diastolic function in children: simultaneous correlation with invasive indices

Objective The purpose of this study was to explore the validity of diastolic indices derived from color M-mode Doppler and Doppler tissue imaging in a heterogeneous group of pediatric patients by comparing them with simultaneously obtained invasive indices of diastolic function. Methods A total of 20 children undergoing left heart catheterization had echocardiographic images recorded simultaneously with high-fidelity left ventricular (LV) pressure tracings. Transmitral Doppler, pulmonary vein Doppler, Doppler tissue imaging, and color M-mode Doppler flow propagation velocity were recorded. LV peak negative dP/dt, the time constant of isovolumic relaxation, and LV end-diastolic pressure were compared with the echocardiographic indices. Results The ratio of peak E-wave mitral velocity/propagation velocity correlated significantly with LV end-diastolic pressure ( r = 0.71; P < .001). Propagation velocity correlated with the time constant of isovolumic relaxation ( r = −0.56; P = .01) and peak negative dP/dt ( r = 0.50; P < .03). Septal mitral annular myocardial velocity correlated significantly with the time constant of isovolumic relaxation ( r = −0.58, P = .01). Conclusion The newer diastolic indices derived from color M-mode Doppler and Doppler tissue imaging appear to be a helpful adjunct in the noninvasive assessment of diastolic function in children.

An evaluation of the use of new doppler methods for detecting longitudinal function abnormalities in a pacing-induced heart failure model

Background Doppler tissue echocardiography and color M-mode Doppler flow propagation velocity have proven useful in evaluating cross-sections of patients with left ventricular (LV) dysfunction, but experience with serial changes is limited. Purpose and methods We tested their use by evaluating the temporal changes of LV function in a pacing-induced congestive heart failure model. Rapid ventricular pacing was initiated and maintained in 20 dogs for 4 weeks. Echocardiography was performed at baseline and weekly during brief pacing cessation. Results With rapid pacing, LV volume significantly increased and ejection fraction (57%-28%), stroke volume (37-18 mL), and mitral annulus systolic velocity (16.1-6.6 cm/s) by Doppler tissue echocardiography significantly decreased, with ejection fraction and mitral annulus systolic velocity closely correlated ( r = 0.706, P < .0001). In contrast to the mitral inflow velocities, mitral annulus early diastolic velocity decreased steadily (12.3-7.3 cm/s) resulting in a dramatic decrease in mitral annulus early/late (1.22-0.57) diastolic velocity with no tendency toward pseudonormalization. The color M-mode Doppler flow propagation velocity also showed significant steady decrease (57-24 cm/s) throughout the pacing period. Multiple regression analysis chose mitral annulus systolic velocity ( r = 0.895, P < .0001) and propagation velocity ( r = 0.782, P < .0001) for the most important factor predicting LV systolic and diastolic function, respectively. Conclusions Doppler tissue echocardiography and color M-mode Doppler flow could evaluate the serial deterioration in LV dysfunction throughout the pacing period. These were more useful in quantifying progressive LV dysfunction than conventional ehocardiographic techniques, and were probably relatively independent of preload. These techniques could be suitable for longitudinal evaluation in addition to the cross-sectional study.

A new echocardiographic method for the assessment of the severity of aortic regurgitation: Color M-mode flow propagation velocity

Purpose: Echocardiographic Doppler methods widely used in assessment of the severity of aortic regurgitation (AR) are considered sensitive and reliable. However, they all have limitations for quantitation of AR. The color M-mode Doppler flow propagation velocity (FPV) method has been shown to provide useful insights in the evaluation of left ventricular diastolic function and appears to be minimally affected with preload changes. Clinical data regarding the value of FPV in the determination of the significance of valvular insuffiencies are lacking. The purpose of this study was to evaluate the use of FPV in measurement of the severity of AR and to compare its reliability with angiography and other echocardiographic methods. Methods: Twenty-nine patients (13 male, 16 female) who had cardiac catheterization for various reasons before echocardiographic evaluation were included. The mean age was 53.6 ± 13.4 years. At the time of cardiac catheterization, the degree of AR was assessed as mild in 10 patients, as moderate in 12, and as severe in 7. In all patients, FPV measurements of AR were obtained with color M-mode Doppler in the apical 5-chamber view. Regurgitation jet height and its ratio to left ventricular outflow obtained in the parasternal long axis with color flow Doppler, pressure half-time, and slope of AR obtained with continuous wave Doppler in apical 5-chamber view were other echocardiographic methods chosen for comparison. Results: The mean values of FPV were 93.1 ± 18.4 cm/s, 49.8 ± 8.0 cm/s, and 31.7 ± 4.9 cm/s in severe, moderate, and mild AR groups, respectively (P <.001). Significant correlation was observed between angiographic grades, FPV, pressure half-time, slope, and jet height and ratio to left ventricular outflow (P <.0001, r = 0.93; P <.0001, r = −0.81; P <.0001, r = 0.76; P <.0001, r = 0.92, respectively). Conclusion: FPV is a simple, practical, and reliable method for the quantification of AR. (J Am Soc Echocardiogr 2002;15:1453-60.)

The left ventricular color M-mode Doppler flow propagation velocity Vp: In vivo comparison of alternative methods including physiologic implications

Three alternative methods have been proposed for determining the “velocity of propagation” (Vp) from color M-mode Doppler transmitral flow images. A quantitative intermethod comparison is performed by using a broad class of images encountered in clinical practice. Vp for 13 subjects was measured by using each of the 3 methods and then statistically compared. Differences among the definitions of Vp generated large differences in its numerical value when computed from the same image. Depending on the choice of method, the value of Vp can vary by as much as 250%. Advantages and limitations of each method are discussed in the context of the physical meaning of Vp. Development of an optimal version of Vp and consensus on how it should be defined merits further attention. This will require a multidisciplinary approach encompassing physiology, fluid dynamics, image processing, and mathematical modeling. (J Am Soc Echocardiogr 2002;15:339-48.)

Preload dependence of color M-Mode Doppler flow propagation velocity in controls and in patients with left ventricular dysfunction

The purpose of this study was to assess the effects of preload alterations on color M-mode flow propagation velocity (Vp) in volunteers with normal left ventricular (LV) function and in patients with depressed LV function. Color M-mode Doppler echocardiography was performed during Valsalva maneuver, passive leg lifting, and after administration of nitroglycerin in 30 healthy volunteers and in 30 age- and sex-matched patients with previous myocardial infarction (MI). Mean Vp in controls was 74 ± 15 cm/s at baseline and 46 ± 15 cm/s in MI patients (P <.0005). In both groups, minor changes in Vp were seen during preload alterations; however, these were not significant (control P =.72, MI P =.31). In both groups, peak E-wave velocity (P <.0005), ratio of early-to-late peak velocities (P <.0005), and E-wave deceleration time (P <.0005) were found to change during preload alterations. In conclusion, we found that in controls and patients with previous MI, the color M-mode flow propagation velocity is not affected significantly by preload. (J Am Soc Echocardiogr 2000;13:902-9.)

Color M-mode Doppler flow propagation velocity is a preload insensitive index of left ventricular relaxation: animal and human validation

OBJECTIVESTo determine the effect of preload in color M-mode Doppler flow propagation velocity (vp).BACKGROUNDThe interpretation of Doppler filling patterns is limited by confounding effects of left ventricular (LV) relaxation and preload. Color M-mode vphas been proposed as a new index of LV relaxation.METHODSWe studied four dogs before and during inferior caval (IVC) occlusion at five different inotropic stages and 14 patients before and during partial cardiopulmonary bypass. Left ventricular (LV) end-diastolic volumes (LV-EDV), the time constant of isovolumic relaxation (tau), left atrial (LA) pre-A and LV end-diastolic pressures (LV-EDP) were measured. Peak velocity during early filling (E) and vpwere extracted by digital analysis of color M-mode Doppler images.RESULTSIn both animals and humans, LV-EDV and LV-EDP decreased significantly from baseline to IVC occlusion (both p < 0.001). Peak early filling (E) velocity decreased in animals from 56 ± 21 to 42 ± 17 cm/s (p < 0.001) without change in vp(from 35 ± 15 to 35 ± 16, p = 0.99). Results were similar in humans (from 69 ± 15 to 53 ± 22 cm/s, p < 0.001, and 37 ± 12 to 34 ± 16, p = 0.30). In both species, there was a strong correlation between LV relaxation (tau) and vp(r = 0.78, p < 0.001, r = 0.86, p < 0.001).CONCLUSIONSOur results indicate that color M-mode Doppler vpis not affected by preload alterations and confirms that LV relaxation is its main physiologic determinant in both animals during varying lusitropic conditions and in humans with heart disease.

Combined use of pulsed and color M-mode doppler echocardiography for the estimation of pulmonary capillary wedge pressure: an empirical approach based on an analytical relation

OBJECTIVESWe sought a noninvasive estimation of pulmonary capillary wedge pressure (Pw) by means of the information obtained from transmitral pulsed Doppler and color M-mode Doppler flow propagation velocity (FPV).BACKGROUNDPulsed Doppler parameters have limited accuracy for the estimation of Pw because they are determined by left atrial pressure and other parameters such as ventricular relaxation. Recently, a good correlation has been found between the rate of ventricular relaxation (τ, tau) and FPV measured by color M-mode Doppler echocardiography.METHODSWe studied 20 patients who underwent invasive hemodynamic monitoring. By multilinear regression analysis, the relationships between Pw and Doppler parameters, FPV, and a noninvasive estimate (Pest) based on the Weiss’ equation (substituting tau for 1/FPV) were determined. A simplified index based on the results obtained was then tested in an additional group of 34 patients.RESULTSBy multiple regression analysis only isovolumic relaxation time (IVRT) (p = 0.0096) and Pest(p = 0.0043) were related to Pw. A derived empirical index, 103/([2·IVRT]+FPV), was strongly correlated with Pw in the entire group according to the regression equation Pw = 4.5·(103/[{2·IVRT} + FPV]) − 9 (r = 0.89, p < 0.0001, [standard error of the estimate] SEE = 3.3 mm Hg). The sensitivity and specificity for the prediction of Pw > 15 mm Hg were 90% and 100%, respectively.CONCLUSIONSThe combined use of FPV as a surrogate for tau and IVRT permits a close prediction of Pw.

Color M-Mode Doppler Flow Propagation Velocity Is a Relatively Preload-Independent Index of Left Ventricular Filling

Standard Doppler indexes of transmitral filling vary in response to alterations in left ventricular (LV) relaxation or preload. To determine whether color M-mode Doppler flow propagation velocity (v p ), a new index of LV relaxation, is affected by preload, we obtained LV volumes, standard Doppler filling indexes, and v p in 20 patients at baseline, during Trendelenburg’s position, inverse Trendelenburg’s position, and after inhalation of amyl nitrite. LV end-diastolic volume decreased from 111 ± 41 mL at baseline and 116 ± 43 mL during Trendelenburg’s position, to 104 ± 40 during inverse Trendelenburg’s maneuver and 92 ± 33 mL after inhalation of amyl nitrite ( P < .0001). Peak early filling velocity decreased from 79 ± 19 cm/s and 90 ± 20 cm/s to 73 ± 22 cm/s and 64 ± 20 cm/s, respectively ( P < 0.0001). In contrast, no significant changes were found in v p (48 ± 24 and 50 ± 26 cm/s vs 48 ± 25 and 48 ± 25 cm/s). We conclude that v p is not affected significantly by preload. Thus v p may provide a more reliable and independent assessment of LV relaxation. (J Am Soc Echocardiogr 1999;12:129-37.)