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New approaches to the Doppler echocardiographic assessment of diastolic function: from research laboratory to clinical practice
Progress in Pediatric Cardiology 10 Ž1999. 105]112
New approaches to the Doppler echocardiographic assessment of diastolic function: from research laboratory to clinical practice Agnes ` Pasquet U , Mario J. Garcia, James D. Thomas Cardio¨ ascular Imaging Center, Department of Cardiology, Cle¨ eland Clinic Foundation, Desk F15, Di¨ ision of Cardiology, 9500 Euclid A¨ enue, Cle¨ eland, OH 44195, USA
Abstract Over the past decade, Doppler echocardiography has become a well-established tool for the diagnosis of left ventricular diastolic dysfunction. Unfortunately, in many clinical situations traditional Doppler indices of transmitral and pulmonary venous flow are inconclusive, primarily due to their dependence on left atrial pressure. Recently, new Doppler indices that are much less dependent on preload have been developed, based on intraventricular flow propagation and intrinsic myocardial velocity. These methodologies provide direct assessment of ventricular relaxation and the small intraventricular pressure gradients essential to efficient filling of the ventricle. We review in this article the theoretical and experiment background of these new echo techniques as well as how they can be implemented in routine clinical practice. Q 1999 Elsevier Science Ireland Ltd. All rights reserved. Keywords: Color M-mode; Tissue Doppler; Diastole
1. Introduction In recent years, echocardiography has emerged as the most common non-invasive method to assess ventricular contraction and filling. Another article in this review has presented the changes in transmitral and pulmonary venous flow patterns occurring during different physiologic or pathologic states. In most cases, careful analysis of Doppler parameters from the mitral inflow and pulmonary venous flow in combination with clinical data allows the correct assessment of diastolic function w1x. Unfortunately, there are several important clinical situations when use of these indices can be confusing.
U
Corresponding author. Tel.: q1-216-445-7288; fax: q1-216445-7306. E-mail address: [email protected] ŽA. Pasquet.
2. Why try to find new methods to assess diastolic function? Mitral inflow is influenced by numerous factors: atrial and ventricular compliance, mitral valve inertance, ventricular relaxation and left atrial pressure, to name a few. Each of these determinants can produce one opposite effect on the transmitral flow pattern, such as when elevated left atrial pressure counteracts delayed ventricular relaxation to produce the ‘pseudonormal’ pattern or when abnormally low left atrial pressure can mimic delayed relaxation even though intrinsic left ventricular function is normal, causing a ‘pseudoabnormal’ pattern. A similar phenomenon has been observed for pulmonary venous flow. In the normal adult, pulmonary venous flow presents a prominent S wave and an SrD ratio ) 1. A blunted S wave is commonly seen in patients with elevated left
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ventricular filling pressure, reduced chamber compliance or severe mitral regurgitation w2x. But because the S wave is also determined by the force of left atrial contractility and relaxation, in normal young adult and athletes, in whom atrial contribution to left ventricular filling is minor, a blunted S wave may be seen in the absence of pathology. In fact, most of the flow-based parameters derived from mitral and pulmonary venous flow have a ‘U-shaped’ relationship with disease severity ŽFig. 1.. Determining whether a patient is on the physiologic or pathologic side of this curve is thus a major challenge w3x. Since this bimodal curve is largely due to the competing effects of preload and ventricular relaxation, much effort has gone into the identification and validation of indices of diastolic function that have less dependence on cardiac preload, so that ventricular relaxation would be more purely demonstrated. Among the modalities that appear most promising are those derived from color M-mode and tissue Doppler imaging, and these will form the bulk of this review.
3. Color M-mode Doppler 3.1. Principles Jacobs et al. w4x, first described the use of color M-mode Doppler to assess left ventricular filling. Color M-mode is an ideal tool to define the propagation of flow during diastole from the atrium to the ventricle because of the high sampling rate and high temporal Ž200 Hz. and spatial Ž- 1 mm. resolution. This spatial velocity map is obtained along a single scan-line that can usually be aligned with the middle of the flow from the atrium to the ventricle ŽFig. 2.. In fact the information displayed by a color M-mode is
Fig. 1. Parabolic curves representing the changes in pulsed Doppler ErA ratio during transition from normal diastolic function to severe diastolic dysfunction. Effect of preload and relaxation.
comparable to the information obtained by multiple simultaneous pulsed Doppler tracings obtained at different levels from the mitral annulus to the apex of the left ventricle. Fig. 3 displays a typical color M-mode pattern in a normal subject in sinus rhythm. Just after the mitral valve opens, a wave of flow propagates from the left atrium to the left ventricle corresponding to early filling ŽE-wave. followed by a second wave with the atrial contraction. The velocities are highest at the level of the mitral valve and decrease when approaching the left ventricular apex. In normal subjects, the spatial position of the maximal velocity is closer to the ventricular apex for early filling ŽE. than it is for atrial contraction ŽA., suggesting that an intraventricular pressure gradient during early filling produces a suction force that accelerates flow beyond the mitral orifice w5x. Flow at the mitral level occurs earlier than at the apical level. The time delay ŽTD. between max velocity at the mitral and apical level is one of the standard indices measured by color M-mode. Another index is the velocity at which flow propagates through the left ventricle Ž ¨ p ., which is represented by the slope of the color wavefront. By using digital post processing software developed for research purpose and not commercially available, intraventricular pressure can be derived from the color M mode w6x. 3.2. How to perform and interpret color M-mode Doppler To record a color M-mode Doppler study, the Mmode cursor is positioned through the center of the mitral annulus in the apical four-chamber view and aligned so as to approximate the vector of flow through the mitral valve ŽFig. 2.. The scanning depth Žusually 16 cm in adults. must be adjusted to visualize the entire left ventricular cavity, and the sweep rate should
Fig. 2. Schematic drawing Žright panel. of the apical 4-chamber view. To optimize the recording of the color M mode, the whole left ventricular cavity must be visualized on the screen. M mode cursor must be positioned in the center of the ventricular inflow through the mitral valve and the Nyquist limit must be set to allow aliasing. The left panel represent a schematic drawing of a color M mode obtained with the cursor positioned as in the right panel.
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Fig. 3. Color M-mode Doppler recording of the left ventricle inflow from a normal subject Ža. and from a patient with cardiomyopathy Žb.. Vp s flow propagation velocity, TDs time delay. In a patient with cardiomyopathy, Vp is lower and TD is increased.
be maximized Ž100]200 mmrs, corresponding to update rates of 2.5]5 ms.. Color velocity scale is adjusted to produce color aliasing Ž0.7]1 mrs in adult population.. Color M-mode maybe recorded on videotape or stored digitally. ¨ p has been variously defined, but in general reflects the slope of any isovelocity contour line passing through the mitral annulus and leaflets. Brun et al. w7x used the slope of the initial transition from no color to color, in effect the lowest isovelocity line Žtypically 3]6 cmrs.. A difficulty with such a low velocity contour is that it may not distinguish the redistribution of flow in the ventricle during isovolumic relaxation from that actually coming through the mitral valve. To avoid this low velocity dependency, Takatsuji et al. w13x and Garcia et al. w14x proposed using an aliasing velocity contour, typically with value approximately 40]100% of the actual Nyquist velocity Židentified by baseline shifting.. Using this contour, ¨ p is then measured from the mitral tips to a position 4 cm distally into the left ventricle. These measurements are generally reproducible but may be limited in patients with delayed AV conduction or tachycardia due to E and A fusion.
3.3. O¨ er¨ iew of the clinical studies using color M-mode Doppler Young healthy subjects typically have a ¨ p ) 55 cmrs w3x. Older patients and those with left ventricular hypertrophy may have lower ¨ p and low pulsed Doppler E velocity and ErA ratio - 1. Patients with advanced diastolic dysfunction Žpseudonormal and restrictive filling patterns with elevated transmitral E and ErA ratio. have lower ¨ p w13x. Indeed Garcia et al. have shown Ervp to be linearly related to mean left atrial pressure. Jacobs et al. w4x first described a delay in flow propagation in the left ventricle in patients with dilated cardiomyopathy. Using color Doppler and Color M-mode, they showed that early filling reached the apex late in diastole or even during the following systole. The suggested mechanisms were an increased size of the left ventricle and disturbed flow through the mitral valve. Brun et al. w7x were the first to relate the left ventricular inflow pattern to the diastolic properties of the myocardium. Using color M-mode and pulsed Doppler, the velocity of flow propagation
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Ž ¨ p . in 30 normal patients was compared to patients with altered ventricular relaxation: dilated cardiomyopathy, ischemic cardiomyopathy, hypertrophic cardiomyopathy, systemic hypertension, and aortic valve disease. Peak transmitral velocities measured by color M-mode and single gated pulsed Doppler correlated very well. The ¨ p was lower in patients Ž0.46" 0.15 mrs. than in normal subjects Ž0.84" 0.11 mrs, P0.0001.. In a subgroup of patients undergoing cardiac catheterization, a significant negative correlation was found between ¨ p and the time constant of relaxation Ž t ., suggesting that a rapid ventricular relaxation Žshort t . promotes a faster propagation of blood into the ventricle. These findings suggest that color Mmode ¨ p could represent a non-invasive index of ventricular relaxation. A different approach to the analysis of color Mmode Doppler was proposed by Stuggaard et al. w8x: rather than measuring ¨ p , they proposed to measure the temporal difference or time delay ŽTD. between the point of maximum velocity at the mitral level and at the apex. The TD is significantly prolonged during acute ischemia in dogs Ž18 " 4 ms before ischemia and 71 " 9 ms during coronary occlusion, P- 0.01.. Similar findings were demonstrated in patients during angioplasty w9x. Concomitant with the increase in TD during angioplasty, the intraventricular velocities recorded along the base]apex direction of the color M-mode have a more abrupt decrease during angioplasty than in the nonischemic ventricle w10x. More recently, this group studied left ventricular inflow in 28 patients with acute myocardial infarction and compared the results to 28 normal controls w11x. The TD was significantly increased inpatients with recent infarction compared to the control group Ž70 " 60 ms vs. 40 " 30 ms, Ps 0.02.. Recent clinical data suggest that color M-mode may also be useful to distinguish patients with constrictive pericarditis from restrictive cardiomyopathy. While having quite similar transmitral Doppler flow patterns, patients with constrictive pericarditis have an extremely rapid ¨ p whereas patients with restrictive cardiomyopathy show a slower ¨ p than their pulsed E wave velocity w12x. Takatsuji compared color M-mode in three groups according to their early to late transmitral flow velocity ratio ŽErA ratio.. Twenty-nine patients formed the control group, along with 34 patients with ejection fraction "60% and ErA ratio - 1, and 25 patients with ejection fraction - 60% and ErA ratio ) 1 Žpseudonormalization. w13x. Color M-mode ¨ p was significantly lower in both patient groups Ž33.8" 13.8 cmrs and 30 " 8.6 cmrs vs. 74.3" 17.4 cmrs, P- 0.001.. Thus, color M-mode ¨ p was able to differentiate patients with pseudo normalization of the ErA profiles from normal patients. In addition there was a strong negative cor-
relation between the t and ¨ p despite the wide range of left ventricular filling pressure among the three groups, suggesting that color M-mode is more independent of preload changes than the standard Doppler indices.
4. Tissue Doppler echocardiography 4.1. Principles Recently the principles of Doppler routinely used for blood flow velocity measurements have been applied to measure tissue velocities. This new technology was proposed by Yamazaki and Mine in 1993. Doppler signals arising from tissue motion differs from blood motion by 2 main characteristics: Ž1. tissue velocities are lower Ž20 cmrs or less. than red cell velocities Ž20]100 cmrs.; and Ž2. the amplitude of the Doppler signal arising from ventricular wall motion is significantly higher than that from blood cells Žapprox. 40 dB or 100 times greater than red blood cells. w15x. Conventional blood flow Doppler uses a high pass filter to remove the low velocities due to wall motion and the weak signal reflected by the blood cells is greatly amplified. By rearranging the filter and the amplification: Žbypass of the high pass filter, lower gain amplification., the Doppler signal reflected by the ventricular walls can be displayed. Tissue Doppler velocities may be displayed either in pulsed, color M-mode, or color two-dimensional mode. The pulsed Doppler display has the advantage of the highest temporal and velocity resolution but requires separate assessment of each part of the myocardium. In contrast, color Doppler has a lower temporal resolution but enables simultaneous interrogation of all myocardial segments in the same echocardiographic view. Color Doppler data are autocorrelated and thus represent mean velocity rather than the full spectrum available from the Fourier processed pulsed Doppler signal. According to the traditional convention for color Doppler, motion directed toward the transducer are encoded in red and away from the transducer are encoded in blue. In fact either pulsed or color tissue Doppler measures the motion of the heart relative to the transducer. This measured motion thus reflects cardiac contraction and relaxation but also translation and rotation of the heart. During the cardiac cycle, global left ventricular motion is directed towards the center of gravity, which is located approximately 69% from the base to the apex along the long axis of the ventricle w16x. This means that the apex is relatively fixed throughout the cardiac cycle with the base and the mitral annulus moving toward the apex. Due to this motion pattern, measurements obtained from the mitral annulus or
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the basal segments of the ventricle represent longitudinal velocity due to cardiac contraction and are minimally affected by translation The normal tissue Doppler profile at the level of the mitral annulus is shown in Fig. 5a. During the systole, there is motion towards the center of gravity of the left ventricle ŽSm. followed by 2 distinct signals directed away from the center of gravity of the left ventricle during early ŽEm. and late ŽAm. diastole. Some additional multiphasic signals can also be seen during isovolumic contraction and relaxation. 4.2. How to perform and interpret a tissue Doppler measurement Most authors w18,21,22x suggest using the apical four or two-chamber window to measure longitudinal myocardial velocities from the mitral annulus. Because tissue Doppler measure a motion relative to the transducer, it is important to minimize the effects of cardiac translation. Therefore, it maybe useful to record the tissue Doppler data during apnea. The sample volume is placed at the level of the mitral annulus either on the septal, lateral, anterior, or inferior wall ŽFig. 4.. Color Doppler may be recorded digitally and post-processed off line using special software, commercially available in some system, to transform the color code into velocity values. Alternatively, pulsed Doppler may be recorded on videotape and measurements are made from the tape or directly during the examination. If the patient has regional wall motion abnormalities, measurements obtained at different sites may be averaged to obtain an index of global ventricular performance. Peak early velocity
Fig. 4. Right panel, schematic drawn showing the position of the sample volume to record tissue Doppler data from the mitral annulus Žlateral wall.. Sample volume can also be placed on the anterior, inferior, septal wall at the level of the mitral annulus. Left panel represent pulsed Doppler obtained at this location: Sm is the systolic component, the two diastolic component are Em and Am.
ŽEm. is measured approximately at the time of the ECG T wave. Peak atrial velocity ŽAm. is the next deflection following the ECG P wave. In normal patients, Em and EmrAm decrease as their mitral equivalent. In patients with pseudonormal filling, Em is lower than in normal patients. 4.3. O¨ er¨ iew of the clinical studies In normal subjects, the diastolic motion of the mitral annulus appears as a mirror image of the mitral inflow wearly diastolic velocity ŽE. and late diastolic velocity ŽA.x. With normal aging, the ventricular velocity EmrAm ratio changes in a manner similar to the mitral ErA ratio w17x. In contrast, in
Fig. 5. Standard pulsed Doppler recorded at the level of the mitral annulus in a normal patient Ž3A. showing the systolic component ŽSm., and the two diastolic component early ŽEm. and late ŽAm.. A similar profile from a patient with a restrictive cardiomyopathy Ž3B. shows a marked reduction of the diastolic components.
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numerous pathologic conditions there is discordance between the myocardial diastolic velocity pattern and the mitral inflow pattern. This can be used to distinguish normal from abnormal ventricular relaxation. Patients with a restrictive cardiomyopathy have low Em regardless of the presence of a high or low E on the mitral velocity profiles w18x. Tissue Doppler has also been shown to differentiate restrictive cardiomyopathy from constrictive pericarditis. Longitudinal myocardial Doppler velocity and mitral Doppler inflow were compared between 15 normal subjects, eight patients with constrictive pericarditis, seven patients with restriction. All had preserved systolic function and a mitral ErA ratio ) 1. Patients with a restrictive cardiomyopathy had a lower Em velocity than normal subjects, while those with constrictive pericarditis had elevated velocities ŽFig. 5b.. A cutoff value of 8 cmrs completely separated patients with restriction from those with constriction w19x. Ragopalan et al. w18x later corroborated these findings in a larger population. Patients with hypertrophic, dilated, or hypertensive cardiomyopathies may also show a dissociation between ventricular and transmitral diastolic velocities w20,21x. Palka et al. w22x reported that myocardial velocities could differentiate ‘physiologic’ hypertrophy in athletes from ‘pathologic’ hypertrophy although there were no differences in the standard Doppler indices. All these previous studies included patients with a wide range of ventricular preload and suggested that contrary to mitral inflow, diastolic myocardial velocities are relatively preload independent. This was confirmed by Oki and al. w23x, who measured mitral inflow and myocardial velocity in 38 patients with heart disease and 12 control subjects undergoing cardiac catheterization. Compared to controls, patients showed a decreased early myocardial velocity ŽEm. measured in the basal posterior wall and a prolonged relaxation time constant Ž t .. The t was correlated to the length of isovolumic relaxation and other standard pulsed Doppler diastolic flow parameters only in patients with normal end diastolic pressure. In contrast, for all patients regardless of the filling pressure there was a strong negative correlation between the time constant relaxation Ž t . and Em. Sohn et al. w21x confirmed the relative preload independence of Em in a subsequent study. They compared the changes in mitral inflow and myocardial
velocities in patients with normal or pseudonormal mitral fillings pattern that occurred with preload alteration by fluid infusion or nitrate administration. Infusion of volume in patients with a mitral pattern of delayed relaxation resulted in a pseudonormal pattern with an increased ErA ratio. Patients with normal or pseudonormal mitral patterns had a reduction in mitral E velocity and ErA ratio after administration of nitrates, while Em was not significantly affected by these changes in preload. Myocardial tissue Doppler had also been proposed as a new method to identify cardiac rejection in heart transplant recipients. Preliminary results show a significant reduction of diastolic myocardial velocity in the case of graft rejection w24x. In our personal experience we have found that tissue Doppler was particularly useful to separate restrictive from constrictive cardiomyopathy. In pure constriction, left ventricular relaxation is preserved and diastolic dysfunction is primary related to impaired left ventricular compliance due to extreme pericardial constraints. It has been mentioned in the past that these two entities can de differentiated by classical Doppler indices but none of the methods previously available were sensitive or specific enough. For example, patients with an advanced stage of restrictive cardiomyopathy and elevated left ventricular fillings pressure have similar mitral inflow and pulmonary flow patterns as patients with constrictive pericarditis. Since the difference between both conditions is that relaxation is preserved in constriction but no in restriction the distinction between the two is important. Because tissue Doppler is not affected by abnormalities of left ventricular compliance, it can be useful in such situations.
5. Relation between color M-mode and tissue Doppler indices and the different stages of diastolic dysfunction Table 1 shows color M-mode parameters and tissue Doppler velocities as integrated in the criteria of diastolic dysfunction recognized by the Canadian consensus on Diastolic Dysfunction w25x.
Table 1 Color M-mode and Tissue Doppler in stages of diastolic dysfunction
ErA cmrs ¨ p cmrs
Em cmrs
Normal young
Normal Adult
Delayed relaxation
Pseudonormal filling
Restrictive filling
)1 ) 55 ) 10
)1 ) 45 )8
-1 - 45 -8
1]2 - 45 -8
)2 - 45 -8
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6. Limitations of these new indexes As with all new methods, both color M-mode Doppler and tissue Doppler need to be studied in larger populations representing the broad spectra of diastolic dysfunction and mixed cardiomyopathy. Color M mode provides global information while tissue Doppler imaging offers regional information. Therefore, in patients with coronary disease and regional wall motion abnormalities, tissue Doppler data may vary from segment to segment. The effect of heart rate, AV conduction and LV geometry on this indices has not been currently addressed. Several technical aspects also need to be sorted out: acquisition and interpretation methods for both color M mode and tissue Doppler need to be standardized. In particular, a careful comparison of color and pulsed tissue Doppler needs to be done to assess whether the velocities reported by both methods are comparable. Preliminary data seem to suggest that both methods are not equivalent: color velocities, which are autocorrelated and thus represent more one average measurement, are lower than velocities obtained with pulsed Doppler w26x. Moreover, algorithms to facilitate analysis and clinical use of both techniques need to be developed and integrated into the echo machines. All the data presented in this review were acquired in a adult population with well defined cardiac disease. There is very little data about the use of tissue Doppler and color M mode in children w27,28x. Moreover, the applicability and usefulness of both methods in the pediatric or congenital heart disease population are largely unknown.
7. Conclusions In the clinical practice, diastolic function is diagnosed in approximately 80% of the patients using clinical data, two-dimensional echo and standard Doppler echo measurements. Both color M-mode flow propagation and tissue Doppler imaging are promising new methodologies that can be used to assess abnormalities of relaxation since they are not affected by left ventricular compliance or preload. These new methods are able to provide additional information that increase the accuracy of a diagnosis of diastolic dysfunction to approximately 95%. Indeed, color Mmode and tissue Doppler echocardiography provided better separation of normal from abnormal with a monotonic decrease in velocity with worsening diastolic dysfunction w29x. While these methods are limited and not largely used or validated, we found that they were most useful to sort out patients with pseudonormal relaxation pattern, by identifying the etiology of
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diastolic dysfunction and providing some clinical and prognostic information. We have enhanced some of the major limitations to a daily use of these new techniques. In the future, larger studies, including pediatric population when combined with the development and integration of new software to automate interpretation, will facilitate the routine use of these new methods. Acknowledgements Supported in part by Grant-in-aid No. NEO-97225-BGIA from the American Heart Association, North-East Ohio Affiliate ŽMJG., National Aeronautics Space Administration Grant No. NCC9-60, Houston, TX ŽJDT, MJG,. and National Institutes of Health Grant No. ROI HL56688-01A1, Bethesda, MD ŽJDT.. References w1x Nishimura RA, Tajik AJ. Evaluation of diastolic filling of left ventricle in health and disease: doppler echocardiography is the clinician’s Rosetta Stone. J Am Coll Cardiol 1997;30:8]18. w2x Basnight MA, Gonzalez MS, Kershenovich SC, Appleton CP. Pulmonary venous flow velocity: relation to hemodynamics, mitral flow velocity and left atrial volume, and ejection fraction. J Am Soc Echocardiogr 1991;4:547]558. w3x Garcia MJ, Thomas JD, Klein AL. New Doppler echocardiographic applications for the study of diastolic function. J Am Coll Cardiol 1998;32:865]875. w4x Jacobs LE, Kotler MN, Parry WR. Flow patterns in dilated cardiomyopathy: a pulsed-wave and color flow Doppler study. J Am Soc Echocardiogr 1990;3:294]302. w5x Courtois M, Ludbrook P. Intravascular pressure transients during relaxation and filling. In: Gaasch WH LWM, editor. Left ventricular diastolic dyfunction and heart faillure. Philadelphia: Lea and Febiger, 1994:150]166. w6x Rossvoll O, Hatle Lk. Pulmonary venoous flow velocities recorded by transthoracic Doppler ultrasound: relation to left ventricular diastolic pressure. J Am Coll Cardiol 1993;21: 1687]1696. w7x Brun P, Tribouilloy C, Duval AM et al. Left ventricular flow propagation during early filling is related to wall relaxation: a color M-mode Doppler analysis. J Am Coll Cardiol 1992; 20:420]432. w8x Stugaard M, Risoe C, Ihlen H, Smiseth OA. Intracavitary filling pattern in the failing left ventricle assessed by color M-mode Doppler echocardiography. J Am Coll Cardiol 1994;24:663]670. w9x Stugaard M, Smiseth OA, Risoe C, Ihlen H. Intraventricular early diastolic filling during acute myocardial ischemia, assessment by multigated color M-mode Doppler echocardiography. Circulation 1993;88:2705]2713. w10x Stugaard M, Smiseth OA, Risoe C, Ihlen H. Intraventricular early diastolic velocity profile during acute myocardial ischemia: a color M-mode Doppler echocardiographic study. J Am Soc Echocardiogr 1995;8:270]279. w11x Steine K, Flogstad T, Stugaard M, Smiseth OA. Early diastolic intraventricular filling pattern in acute myocardial infarction by color M-mode Doppler echocardiography. J Am Soc Echocardiogr 1998;11:119]125. w12x Rodriguez L, Ares M, Vandervoort PM, Thomas JD, Greenberg N, Klein A. Does color M-mode flow propagation dif-
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w13x
w14x
w15x w16x w17x
w18x
w19x
w20x
A. Pasquet et al. r Progress in Pediatric Cardiology 10 (1999) 105]112 ferentiate between patients with restrictive and constrictive physiology. J Am Coll Cardiol 1994;24:663]670. Takatsuji H, Mikami T, Urasawa K et al. A new approach for evaluation of left ventricular diastolic function: spatial and temporal analysis of left ventricular filling flow propagation by color M-mode Doppler echocardiography wsee commentsx. J Am Coll Cardiol 1996;27:365]371. Garcia MJ, Ares MA, Asher C, Rodriguez L, Vandervoort P, Thomas JD. An index of early left ventricular filling that combined with pulsed Doppler peak E velocity may estimate capillary wedge pressure. J Am Coll Cardiol 1997;29:448]454. Yamazaki N, Mine Y, Sano A, Hirama M. Analysis of wall motion using color coded tissue Doppler imaging system. Jpn J Appl Phys 1994;33:3141]3146. Drozdz J. Normal pattern of myocardial velocity. In: Erbel RNH, Drozdz J, editors. Atlas of tissue Doppler echocardaiography ŽTDE.. Darmstadt: Steinkofverlag, 1995:69]90. Isaaz K, Munoz del Romeral L, Lee E, Schiller N. Quantitation of the motion of the cardiac base in normal subject by Doppler echocardiography. J Am Soc Echocardiogr 1993;6: 166]176. Ragopalan N, Garcia M, Ares MA, Murray RD, Klein AL. Comparison of Doppler echocardiographic methods to differentiate constrictive pericarditis from restrictive cardiomyopathy. J Am Coll Cardiol 1998;31:164A. Garcia MJ, Rodriguez L, Ares M, Griffin BP, Thomas JD. Differenciation of constrictive pericarditis from restrictive cardiomyopathy assessment of left ventricular diastolic velocities in the longitudinal axis by tissue Doppler imaging. J Am Coll Cardiol 1996;27:108]114. Rodriguez L, Garcia M, Ares M, Griffin BP, Nakatani S, Thomas JD. Assessment of mitral annular dynamics during diastole by Doppler tissue imaging: comparison with mitral Doppler inflow in subjects without heart disease and in patients with left ventricular hypertrophy. Am Heart J 1996;131:982]987.
w21x Sohn DW, Chai IH, Lee DJ et al. Assessment of mitral annulus velocity by Doppler tissue imaging in the evaluation of left ventricular diastolic function. J Am Coll Cardiol 1997;30:474]480. w22x Palka P, Lange A, Fleming AD et al. Differences in myocardial velocity gradient measured throughout the cardiac cycle in patients with hypertrophic cardiomyopathy, athletes and patients with left ventricular hypertrophy due to hypertension. J Am Coll Cardiol 1997;30:760]768. w23x Oki T, Tabata T, Yamada H et al. Clinical application of pulsed Doppler tissue imaging for assessing abnormal left ventricular relaxation wsee commentsx. Am J Cardiol 1997; 79:921]928. w24x Mankad SMS, Mandarino WA, Kormos KL, Gorscan III J. Assessment of acute cardiac allograft rejection by quantitative tissue Doppler echocardiography. Circulation 1997: I]342. w25x Rakowski H, Appelton C, Chan KL et al. Canadian consensus recommendation for the measurement and reporting of diastolic dysfunction by echocardiography Žreview.. J Am Soc Echocardiogr 1996;9:736]760. w26x Kukulski T, Wilkenshoff U, Wigstrom L, Hatle B, Wranne G, Sutherland G. A comparison of segmental velocity data derived by pulsed or color Doppler myocardial imaging. Are they interchangeable in experimental and clinical settings? Echocardiography 1998;15Ž2.:S41. w27x Rychik J, Tian ZY. Quantitative assessment of myocardial tissue velocities in normal children with Doppler tissue imaging. Am J Cardiol 1996;77:1254]1257. w28x Okajima Y, Suzuki K, Fujiwara T, Matsuo K, Uchita S, Aotsuka H. Color M mode analysis of left ventricular inflow in pediatric patients ŽJapanese, English abstract .. J Cardiol 1998;32:181]188. w29x Farias CA, Rodriguez L, Garcia MJ, Sun JP, Klein AL, Thomas JD. Comparison of standard Doppler and tissue Doppler echocardiography in the assessment of diastolic function. J Am Soc Echocardiogr, in press.
New approaches to the Doppler echocardiographic assessment of diastolic function: from research laboratory to clinical practice Agnes ` Pasquet U , Mario J. Garcia, James D. Thomas Cardio¨ ascular Imaging Center, Department of Cardiology, Cle¨ eland Clinic Foundation, Desk F15, Di¨ ision of Cardiology, 9500 Euclid A¨ enue, Cle¨ eland, OH 44195, USA
Abstract Over the past decade, Doppler echocardiography has become a well-established tool for the diagnosis of left ventricular diastolic dysfunction. Unfortunately, in many clinical situations traditional Doppler indices of transmitral and pulmonary venous flow are inconclusive, primarily due to their dependence on left atrial pressure. Recently, new Doppler indices that are much less dependent on preload have been developed, based on intraventricular flow propagation and intrinsic myocardial velocity. These methodologies provide direct assessment of ventricular relaxation and the small intraventricular pressure gradients essential to efficient filling of the ventricle. We review in this article the theoretical and experiment background of these new echo techniques as well as how they can be implemented in routine clinical practice. Q 1999 Elsevier Science Ireland Ltd. All rights reserved. Keywords: Color M-mode; Tissue Doppler; Diastole
1. Introduction In recent years, echocardiography has emerged as the most common non-invasive method to assess ventricular contraction and filling. Another article in this review has presented the changes in transmitral and pulmonary venous flow patterns occurring during different physiologic or pathologic states. In most cases, careful analysis of Doppler parameters from the mitral inflow and pulmonary venous flow in combination with clinical data allows the correct assessment of diastolic function w1x. Unfortunately, there are several important clinical situations when use of these indices can be confusing.
U
Corresponding author. Tel.: q1-216-445-7288; fax: q1-216445-7306. E-mail address: [email protected] ŽA. Pasquet.
2. Why try to find new methods to assess diastolic function? Mitral inflow is influenced by numerous factors: atrial and ventricular compliance, mitral valve inertance, ventricular relaxation and left atrial pressure, to name a few. Each of these determinants can produce one opposite effect on the transmitral flow pattern, such as when elevated left atrial pressure counteracts delayed ventricular relaxation to produce the ‘pseudonormal’ pattern or when abnormally low left atrial pressure can mimic delayed relaxation even though intrinsic left ventricular function is normal, causing a ‘pseudoabnormal’ pattern. A similar phenomenon has been observed for pulmonary venous flow. In the normal adult, pulmonary venous flow presents a prominent S wave and an SrD ratio ) 1. A blunted S wave is commonly seen in patients with elevated left
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A. Pasquet et al. r Progress in Pediatric Cardiology 10 (1999) 105]112
ventricular filling pressure, reduced chamber compliance or severe mitral regurgitation w2x. But because the S wave is also determined by the force of left atrial contractility and relaxation, in normal young adult and athletes, in whom atrial contribution to left ventricular filling is minor, a blunted S wave may be seen in the absence of pathology. In fact, most of the flow-based parameters derived from mitral and pulmonary venous flow have a ‘U-shaped’ relationship with disease severity ŽFig. 1.. Determining whether a patient is on the physiologic or pathologic side of this curve is thus a major challenge w3x. Since this bimodal curve is largely due to the competing effects of preload and ventricular relaxation, much effort has gone into the identification and validation of indices of diastolic function that have less dependence on cardiac preload, so that ventricular relaxation would be more purely demonstrated. Among the modalities that appear most promising are those derived from color M-mode and tissue Doppler imaging, and these will form the bulk of this review.
3. Color M-mode Doppler 3.1. Principles Jacobs et al. w4x, first described the use of color M-mode Doppler to assess left ventricular filling. Color M-mode is an ideal tool to define the propagation of flow during diastole from the atrium to the ventricle because of the high sampling rate and high temporal Ž200 Hz. and spatial Ž- 1 mm. resolution. This spatial velocity map is obtained along a single scan-line that can usually be aligned with the middle of the flow from the atrium to the ventricle ŽFig. 2.. In fact the information displayed by a color M-mode is
Fig. 1. Parabolic curves representing the changes in pulsed Doppler ErA ratio during transition from normal diastolic function to severe diastolic dysfunction. Effect of preload and relaxation.
comparable to the information obtained by multiple simultaneous pulsed Doppler tracings obtained at different levels from the mitral annulus to the apex of the left ventricle. Fig. 3 displays a typical color M-mode pattern in a normal subject in sinus rhythm. Just after the mitral valve opens, a wave of flow propagates from the left atrium to the left ventricle corresponding to early filling ŽE-wave. followed by a second wave with the atrial contraction. The velocities are highest at the level of the mitral valve and decrease when approaching the left ventricular apex. In normal subjects, the spatial position of the maximal velocity is closer to the ventricular apex for early filling ŽE. than it is for atrial contraction ŽA., suggesting that an intraventricular pressure gradient during early filling produces a suction force that accelerates flow beyond the mitral orifice w5x. Flow at the mitral level occurs earlier than at the apical level. The time delay ŽTD. between max velocity at the mitral and apical level is one of the standard indices measured by color M-mode. Another index is the velocity at which flow propagates through the left ventricle Ž ¨ p ., which is represented by the slope of the color wavefront. By using digital post processing software developed for research purpose and not commercially available, intraventricular pressure can be derived from the color M mode w6x. 3.2. How to perform and interpret color M-mode Doppler To record a color M-mode Doppler study, the Mmode cursor is positioned through the center of the mitral annulus in the apical four-chamber view and aligned so as to approximate the vector of flow through the mitral valve ŽFig. 2.. The scanning depth Žusually 16 cm in adults. must be adjusted to visualize the entire left ventricular cavity, and the sweep rate should
Fig. 2. Schematic drawing Žright panel. of the apical 4-chamber view. To optimize the recording of the color M mode, the whole left ventricular cavity must be visualized on the screen. M mode cursor must be positioned in the center of the ventricular inflow through the mitral valve and the Nyquist limit must be set to allow aliasing. The left panel represent a schematic drawing of a color M mode obtained with the cursor positioned as in the right panel.
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Fig. 3. Color M-mode Doppler recording of the left ventricle inflow from a normal subject Ža. and from a patient with cardiomyopathy Žb.. Vp s flow propagation velocity, TDs time delay. In a patient with cardiomyopathy, Vp is lower and TD is increased.
be maximized Ž100]200 mmrs, corresponding to update rates of 2.5]5 ms.. Color velocity scale is adjusted to produce color aliasing Ž0.7]1 mrs in adult population.. Color M-mode maybe recorded on videotape or stored digitally. ¨ p has been variously defined, but in general reflects the slope of any isovelocity contour line passing through the mitral annulus and leaflets. Brun et al. w7x used the slope of the initial transition from no color to color, in effect the lowest isovelocity line Žtypically 3]6 cmrs.. A difficulty with such a low velocity contour is that it may not distinguish the redistribution of flow in the ventricle during isovolumic relaxation from that actually coming through the mitral valve. To avoid this low velocity dependency, Takatsuji et al. w13x and Garcia et al. w14x proposed using an aliasing velocity contour, typically with value approximately 40]100% of the actual Nyquist velocity Židentified by baseline shifting.. Using this contour, ¨ p is then measured from the mitral tips to a position 4 cm distally into the left ventricle. These measurements are generally reproducible but may be limited in patients with delayed AV conduction or tachycardia due to E and A fusion.
3.3. O¨ er¨ iew of the clinical studies using color M-mode Doppler Young healthy subjects typically have a ¨ p ) 55 cmrs w3x. Older patients and those with left ventricular hypertrophy may have lower ¨ p and low pulsed Doppler E velocity and ErA ratio - 1. Patients with advanced diastolic dysfunction Žpseudonormal and restrictive filling patterns with elevated transmitral E and ErA ratio. have lower ¨ p w13x. Indeed Garcia et al. have shown Ervp to be linearly related to mean left atrial pressure. Jacobs et al. w4x first described a delay in flow propagation in the left ventricle in patients with dilated cardiomyopathy. Using color Doppler and Color M-mode, they showed that early filling reached the apex late in diastole or even during the following systole. The suggested mechanisms were an increased size of the left ventricle and disturbed flow through the mitral valve. Brun et al. w7x were the first to relate the left ventricular inflow pattern to the diastolic properties of the myocardium. Using color M-mode and pulsed Doppler, the velocity of flow propagation
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Ž ¨ p . in 30 normal patients was compared to patients with altered ventricular relaxation: dilated cardiomyopathy, ischemic cardiomyopathy, hypertrophic cardiomyopathy, systemic hypertension, and aortic valve disease. Peak transmitral velocities measured by color M-mode and single gated pulsed Doppler correlated very well. The ¨ p was lower in patients Ž0.46" 0.15 mrs. than in normal subjects Ž0.84" 0.11 mrs, P0.0001.. In a subgroup of patients undergoing cardiac catheterization, a significant negative correlation was found between ¨ p and the time constant of relaxation Ž t ., suggesting that a rapid ventricular relaxation Žshort t . promotes a faster propagation of blood into the ventricle. These findings suggest that color Mmode ¨ p could represent a non-invasive index of ventricular relaxation. A different approach to the analysis of color Mmode Doppler was proposed by Stuggaard et al. w8x: rather than measuring ¨ p , they proposed to measure the temporal difference or time delay ŽTD. between the point of maximum velocity at the mitral level and at the apex. The TD is significantly prolonged during acute ischemia in dogs Ž18 " 4 ms before ischemia and 71 " 9 ms during coronary occlusion, P- 0.01.. Similar findings were demonstrated in patients during angioplasty w9x. Concomitant with the increase in TD during angioplasty, the intraventricular velocities recorded along the base]apex direction of the color M-mode have a more abrupt decrease during angioplasty than in the nonischemic ventricle w10x. More recently, this group studied left ventricular inflow in 28 patients with acute myocardial infarction and compared the results to 28 normal controls w11x. The TD was significantly increased inpatients with recent infarction compared to the control group Ž70 " 60 ms vs. 40 " 30 ms, Ps 0.02.. Recent clinical data suggest that color M-mode may also be useful to distinguish patients with constrictive pericarditis from restrictive cardiomyopathy. While having quite similar transmitral Doppler flow patterns, patients with constrictive pericarditis have an extremely rapid ¨ p whereas patients with restrictive cardiomyopathy show a slower ¨ p than their pulsed E wave velocity w12x. Takatsuji compared color M-mode in three groups according to their early to late transmitral flow velocity ratio ŽErA ratio.. Twenty-nine patients formed the control group, along with 34 patients with ejection fraction "60% and ErA ratio - 1, and 25 patients with ejection fraction - 60% and ErA ratio ) 1 Žpseudonormalization. w13x. Color M-mode ¨ p was significantly lower in both patient groups Ž33.8" 13.8 cmrs and 30 " 8.6 cmrs vs. 74.3" 17.4 cmrs, P- 0.001.. Thus, color M-mode ¨ p was able to differentiate patients with pseudo normalization of the ErA profiles from normal patients. In addition there was a strong negative cor-
relation between the t and ¨ p despite the wide range of left ventricular filling pressure among the three groups, suggesting that color M-mode is more independent of preload changes than the standard Doppler indices.
4. Tissue Doppler echocardiography 4.1. Principles Recently the principles of Doppler routinely used for blood flow velocity measurements have been applied to measure tissue velocities. This new technology was proposed by Yamazaki and Mine in 1993. Doppler signals arising from tissue motion differs from blood motion by 2 main characteristics: Ž1. tissue velocities are lower Ž20 cmrs or less. than red cell velocities Ž20]100 cmrs.; and Ž2. the amplitude of the Doppler signal arising from ventricular wall motion is significantly higher than that from blood cells Žapprox. 40 dB or 100 times greater than red blood cells. w15x. Conventional blood flow Doppler uses a high pass filter to remove the low velocities due to wall motion and the weak signal reflected by the blood cells is greatly amplified. By rearranging the filter and the amplification: Žbypass of the high pass filter, lower gain amplification., the Doppler signal reflected by the ventricular walls can be displayed. Tissue Doppler velocities may be displayed either in pulsed, color M-mode, or color two-dimensional mode. The pulsed Doppler display has the advantage of the highest temporal and velocity resolution but requires separate assessment of each part of the myocardium. In contrast, color Doppler has a lower temporal resolution but enables simultaneous interrogation of all myocardial segments in the same echocardiographic view. Color Doppler data are autocorrelated and thus represent mean velocity rather than the full spectrum available from the Fourier processed pulsed Doppler signal. According to the traditional convention for color Doppler, motion directed toward the transducer are encoded in red and away from the transducer are encoded in blue. In fact either pulsed or color tissue Doppler measures the motion of the heart relative to the transducer. This measured motion thus reflects cardiac contraction and relaxation but also translation and rotation of the heart. During the cardiac cycle, global left ventricular motion is directed towards the center of gravity, which is located approximately 69% from the base to the apex along the long axis of the ventricle w16x. This means that the apex is relatively fixed throughout the cardiac cycle with the base and the mitral annulus moving toward the apex. Due to this motion pattern, measurements obtained from the mitral annulus or
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the basal segments of the ventricle represent longitudinal velocity due to cardiac contraction and are minimally affected by translation The normal tissue Doppler profile at the level of the mitral annulus is shown in Fig. 5a. During the systole, there is motion towards the center of gravity of the left ventricle ŽSm. followed by 2 distinct signals directed away from the center of gravity of the left ventricle during early ŽEm. and late ŽAm. diastole. Some additional multiphasic signals can also be seen during isovolumic contraction and relaxation. 4.2. How to perform and interpret a tissue Doppler measurement Most authors w18,21,22x suggest using the apical four or two-chamber window to measure longitudinal myocardial velocities from the mitral annulus. Because tissue Doppler measure a motion relative to the transducer, it is important to minimize the effects of cardiac translation. Therefore, it maybe useful to record the tissue Doppler data during apnea. The sample volume is placed at the level of the mitral annulus either on the septal, lateral, anterior, or inferior wall ŽFig. 4.. Color Doppler may be recorded digitally and post-processed off line using special software, commercially available in some system, to transform the color code into velocity values. Alternatively, pulsed Doppler may be recorded on videotape and measurements are made from the tape or directly during the examination. If the patient has regional wall motion abnormalities, measurements obtained at different sites may be averaged to obtain an index of global ventricular performance. Peak early velocity
Fig. 4. Right panel, schematic drawn showing the position of the sample volume to record tissue Doppler data from the mitral annulus Žlateral wall.. Sample volume can also be placed on the anterior, inferior, septal wall at the level of the mitral annulus. Left panel represent pulsed Doppler obtained at this location: Sm is the systolic component, the two diastolic component are Em and Am.
ŽEm. is measured approximately at the time of the ECG T wave. Peak atrial velocity ŽAm. is the next deflection following the ECG P wave. In normal patients, Em and EmrAm decrease as their mitral equivalent. In patients with pseudonormal filling, Em is lower than in normal patients. 4.3. O¨ er¨ iew of the clinical studies In normal subjects, the diastolic motion of the mitral annulus appears as a mirror image of the mitral inflow wearly diastolic velocity ŽE. and late diastolic velocity ŽA.x. With normal aging, the ventricular velocity EmrAm ratio changes in a manner similar to the mitral ErA ratio w17x. In contrast, in
Fig. 5. Standard pulsed Doppler recorded at the level of the mitral annulus in a normal patient Ž3A. showing the systolic component ŽSm., and the two diastolic component early ŽEm. and late ŽAm.. A similar profile from a patient with a restrictive cardiomyopathy Ž3B. shows a marked reduction of the diastolic components.
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numerous pathologic conditions there is discordance between the myocardial diastolic velocity pattern and the mitral inflow pattern. This can be used to distinguish normal from abnormal ventricular relaxation. Patients with a restrictive cardiomyopathy have low Em regardless of the presence of a high or low E on the mitral velocity profiles w18x. Tissue Doppler has also been shown to differentiate restrictive cardiomyopathy from constrictive pericarditis. Longitudinal myocardial Doppler velocity and mitral Doppler inflow were compared between 15 normal subjects, eight patients with constrictive pericarditis, seven patients with restriction. All had preserved systolic function and a mitral ErA ratio ) 1. Patients with a restrictive cardiomyopathy had a lower Em velocity than normal subjects, while those with constrictive pericarditis had elevated velocities ŽFig. 5b.. A cutoff value of 8 cmrs completely separated patients with restriction from those with constriction w19x. Ragopalan et al. w18x later corroborated these findings in a larger population. Patients with hypertrophic, dilated, or hypertensive cardiomyopathies may also show a dissociation between ventricular and transmitral diastolic velocities w20,21x. Palka et al. w22x reported that myocardial velocities could differentiate ‘physiologic’ hypertrophy in athletes from ‘pathologic’ hypertrophy although there were no differences in the standard Doppler indices. All these previous studies included patients with a wide range of ventricular preload and suggested that contrary to mitral inflow, diastolic myocardial velocities are relatively preload independent. This was confirmed by Oki and al. w23x, who measured mitral inflow and myocardial velocity in 38 patients with heart disease and 12 control subjects undergoing cardiac catheterization. Compared to controls, patients showed a decreased early myocardial velocity ŽEm. measured in the basal posterior wall and a prolonged relaxation time constant Ž t .. The t was correlated to the length of isovolumic relaxation and other standard pulsed Doppler diastolic flow parameters only in patients with normal end diastolic pressure. In contrast, for all patients regardless of the filling pressure there was a strong negative correlation between the time constant relaxation Ž t . and Em. Sohn et al. w21x confirmed the relative preload independence of Em in a subsequent study. They compared the changes in mitral inflow and myocardial
velocities in patients with normal or pseudonormal mitral fillings pattern that occurred with preload alteration by fluid infusion or nitrate administration. Infusion of volume in patients with a mitral pattern of delayed relaxation resulted in a pseudonormal pattern with an increased ErA ratio. Patients with normal or pseudonormal mitral patterns had a reduction in mitral E velocity and ErA ratio after administration of nitrates, while Em was not significantly affected by these changes in preload. Myocardial tissue Doppler had also been proposed as a new method to identify cardiac rejection in heart transplant recipients. Preliminary results show a significant reduction of diastolic myocardial velocity in the case of graft rejection w24x. In our personal experience we have found that tissue Doppler was particularly useful to separate restrictive from constrictive cardiomyopathy. In pure constriction, left ventricular relaxation is preserved and diastolic dysfunction is primary related to impaired left ventricular compliance due to extreme pericardial constraints. It has been mentioned in the past that these two entities can de differentiated by classical Doppler indices but none of the methods previously available were sensitive or specific enough. For example, patients with an advanced stage of restrictive cardiomyopathy and elevated left ventricular fillings pressure have similar mitral inflow and pulmonary flow patterns as patients with constrictive pericarditis. Since the difference between both conditions is that relaxation is preserved in constriction but no in restriction the distinction between the two is important. Because tissue Doppler is not affected by abnormalities of left ventricular compliance, it can be useful in such situations.
5. Relation between color M-mode and tissue Doppler indices and the different stages of diastolic dysfunction Table 1 shows color M-mode parameters and tissue Doppler velocities as integrated in the criteria of diastolic dysfunction recognized by the Canadian consensus on Diastolic Dysfunction w25x.
Table 1 Color M-mode and Tissue Doppler in stages of diastolic dysfunction
ErA cmrs ¨ p cmrs
Em cmrs
Normal young
Normal Adult
Delayed relaxation
Pseudonormal filling
Restrictive filling
)1 ) 55 ) 10
)1 ) 45 )8
-1 - 45 -8
1]2 - 45 -8
)2 - 45 -8
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6. Limitations of these new indexes As with all new methods, both color M-mode Doppler and tissue Doppler need to be studied in larger populations representing the broad spectra of diastolic dysfunction and mixed cardiomyopathy. Color M mode provides global information while tissue Doppler imaging offers regional information. Therefore, in patients with coronary disease and regional wall motion abnormalities, tissue Doppler data may vary from segment to segment. The effect of heart rate, AV conduction and LV geometry on this indices has not been currently addressed. Several technical aspects also need to be sorted out: acquisition and interpretation methods for both color M mode and tissue Doppler need to be standardized. In particular, a careful comparison of color and pulsed tissue Doppler needs to be done to assess whether the velocities reported by both methods are comparable. Preliminary data seem to suggest that both methods are not equivalent: color velocities, which are autocorrelated and thus represent more one average measurement, are lower than velocities obtained with pulsed Doppler w26x. Moreover, algorithms to facilitate analysis and clinical use of both techniques need to be developed and integrated into the echo machines. All the data presented in this review were acquired in a adult population with well defined cardiac disease. There is very little data about the use of tissue Doppler and color M mode in children w27,28x. Moreover, the applicability and usefulness of both methods in the pediatric or congenital heart disease population are largely unknown.
7. Conclusions In the clinical practice, diastolic function is diagnosed in approximately 80% of the patients using clinical data, two-dimensional echo and standard Doppler echo measurements. Both color M-mode flow propagation and tissue Doppler imaging are promising new methodologies that can be used to assess abnormalities of relaxation since they are not affected by left ventricular compliance or preload. These new methods are able to provide additional information that increase the accuracy of a diagnosis of diastolic dysfunction to approximately 95%. Indeed, color Mmode and tissue Doppler echocardiography provided better separation of normal from abnormal with a monotonic decrease in velocity with worsening diastolic dysfunction w29x. While these methods are limited and not largely used or validated, we found that they were most useful to sort out patients with pseudonormal relaxation pattern, by identifying the etiology of
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diastolic dysfunction and providing some clinical and prognostic information. We have enhanced some of the major limitations to a daily use of these new techniques. In the future, larger studies, including pediatric population when combined with the development and integration of new software to automate interpretation, will facilitate the routine use of these new methods. Acknowledgements Supported in part by Grant-in-aid No. NEO-97225-BGIA from the American Heart Association, North-East Ohio Affiliate ŽMJG., National Aeronautics Space Administration Grant No. NCC9-60, Houston, TX ŽJDT, MJG,. and National Institutes of Health Grant No. ROI HL56688-01A1, Bethesda, MD ŽJDT.. References w1x Nishimura RA, Tajik AJ. Evaluation of diastolic filling of left ventricle in health and disease: doppler echocardiography is the clinician’s Rosetta Stone. J Am Coll Cardiol 1997;30:8]18. w2x Basnight MA, Gonzalez MS, Kershenovich SC, Appleton CP. Pulmonary venous flow velocity: relation to hemodynamics, mitral flow velocity and left atrial volume, and ejection fraction. J Am Soc Echocardiogr 1991;4:547]558. w3x Garcia MJ, Thomas JD, Klein AL. New Doppler echocardiographic applications for the study of diastolic function. J Am Coll Cardiol 1998;32:865]875. w4x Jacobs LE, Kotler MN, Parry WR. Flow patterns in dilated cardiomyopathy: a pulsed-wave and color flow Doppler study. J Am Soc Echocardiogr 1990;3:294]302. w5x Courtois M, Ludbrook P. Intravascular pressure transients during relaxation and filling. In: Gaasch WH LWM, editor. Left ventricular diastolic dyfunction and heart faillure. Philadelphia: Lea and Febiger, 1994:150]166. w6x Rossvoll O, Hatle Lk. Pulmonary venoous flow velocities recorded by transthoracic Doppler ultrasound: relation to left ventricular diastolic pressure. J Am Coll Cardiol 1993;21: 1687]1696. w7x Brun P, Tribouilloy C, Duval AM et al. Left ventricular flow propagation during early filling is related to wall relaxation: a color M-mode Doppler analysis. J Am Coll Cardiol 1992; 20:420]432. w8x Stugaard M, Risoe C, Ihlen H, Smiseth OA. Intracavitary filling pattern in the failing left ventricle assessed by color M-mode Doppler echocardiography. J Am Coll Cardiol 1994;24:663]670. w9x Stugaard M, Smiseth OA, Risoe C, Ihlen H. Intraventricular early diastolic filling during acute myocardial ischemia, assessment by multigated color M-mode Doppler echocardiography. Circulation 1993;88:2705]2713. w10x Stugaard M, Smiseth OA, Risoe C, Ihlen H. Intraventricular early diastolic velocity profile during acute myocardial ischemia: a color M-mode Doppler echocardiographic study. J Am Soc Echocardiogr 1995;8:270]279. w11x Steine K, Flogstad T, Stugaard M, Smiseth OA. Early diastolic intraventricular filling pattern in acute myocardial infarction by color M-mode Doppler echocardiography. J Am Soc Echocardiogr 1998;11:119]125. w12x Rodriguez L, Ares M, Vandervoort PM, Thomas JD, Greenberg N, Klein A. Does color M-mode flow propagation dif-
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A. Pasquet et al. r Progress in Pediatric Cardiology 10 (1999) 105]112 ferentiate between patients with restrictive and constrictive physiology. J Am Coll Cardiol 1994;24:663]670. Takatsuji H, Mikami T, Urasawa K et al. A new approach for evaluation of left ventricular diastolic function: spatial and temporal analysis of left ventricular filling flow propagation by color M-mode Doppler echocardiography wsee commentsx. J Am Coll Cardiol 1996;27:365]371. Garcia MJ, Ares MA, Asher C, Rodriguez L, Vandervoort P, Thomas JD. An index of early left ventricular filling that combined with pulsed Doppler peak E velocity may estimate capillary wedge pressure. J Am Coll Cardiol 1997;29:448]454. Yamazaki N, Mine Y, Sano A, Hirama M. Analysis of wall motion using color coded tissue Doppler imaging system. Jpn J Appl Phys 1994;33:3141]3146. Drozdz J. Normal pattern of myocardial velocity. In: Erbel RNH, Drozdz J, editors. Atlas of tissue Doppler echocardaiography ŽTDE.. Darmstadt: Steinkofverlag, 1995:69]90. Isaaz K, Munoz del Romeral L, Lee E, Schiller N. Quantitation of the motion of the cardiac base in normal subject by Doppler echocardiography. J Am Soc Echocardiogr 1993;6: 166]176. Ragopalan N, Garcia M, Ares MA, Murray RD, Klein AL. Comparison of Doppler echocardiographic methods to differentiate constrictive pericarditis from restrictive cardiomyopathy. J Am Coll Cardiol 1998;31:164A. Garcia MJ, Rodriguez L, Ares M, Griffin BP, Thomas JD. Differenciation of constrictive pericarditis from restrictive cardiomyopathy assessment of left ventricular diastolic velocities in the longitudinal axis by tissue Doppler imaging. J Am Coll Cardiol 1996;27:108]114. Rodriguez L, Garcia M, Ares M, Griffin BP, Nakatani S, Thomas JD. Assessment of mitral annular dynamics during diastole by Doppler tissue imaging: comparison with mitral Doppler inflow in subjects without heart disease and in patients with left ventricular hypertrophy. Am Heart J 1996;131:982]987.
w21x Sohn DW, Chai IH, Lee DJ et al. Assessment of mitral annulus velocity by Doppler tissue imaging in the evaluation of left ventricular diastolic function. J Am Coll Cardiol 1997;30:474]480. w22x Palka P, Lange A, Fleming AD et al. Differences in myocardial velocity gradient measured throughout the cardiac cycle in patients with hypertrophic cardiomyopathy, athletes and patients with left ventricular hypertrophy due to hypertension. J Am Coll Cardiol 1997;30:760]768. w23x Oki T, Tabata T, Yamada H et al. Clinical application of pulsed Doppler tissue imaging for assessing abnormal left ventricular relaxation wsee commentsx. Am J Cardiol 1997; 79:921]928. w24x Mankad SMS, Mandarino WA, Kormos KL, Gorscan III J. Assessment of acute cardiac allograft rejection by quantitative tissue Doppler echocardiography. Circulation 1997: I]342. w25x Rakowski H, Appelton C, Chan KL et al. Canadian consensus recommendation for the measurement and reporting of diastolic dysfunction by echocardiography Žreview.. J Am Soc Echocardiogr 1996;9:736]760. w26x Kukulski T, Wilkenshoff U, Wigstrom L, Hatle B, Wranne G, Sutherland G. A comparison of segmental velocity data derived by pulsed or color Doppler myocardial imaging. Are they interchangeable in experimental and clinical settings? Echocardiography 1998;15Ž2.:S41. w27x Rychik J, Tian ZY. Quantitative assessment of myocardial tissue velocities in normal children with Doppler tissue imaging. Am J Cardiol 1996;77:1254]1257. w28x Okajima Y, Suzuki K, Fujiwara T, Matsuo K, Uchita S, Aotsuka H. Color M mode analysis of left ventricular inflow in pediatric patients ŽJapanese, English abstract .. J Cardiol 1998;32:181]188. w29x Farias CA, Rodriguez L, Garcia MJ, Sun JP, Klein AL, Thomas JD. Comparison of standard Doppler and tissue Doppler echocardiography in the assessment of diastolic function. J Am Soc Echocardiogr, in press.