Archived Comments for:
Current clinical applications of spectral tissue Doppler echocardiography (E/E' ratio) as a noninvasive surrogate for left ventricular diastolic pressures in the diagnosis of heart failure with preserved left ventricular systolic function
George Thomas, Department of Cardiology, Indira Gandhi Co-operative Hospital, Kochi 682 020, India
10 April 2007
I read with great interest the review article “Current clinical applications of spectral tissue Doppler echocardiography (E/E' ratio) as a noninvasive surrogate for left ventricular diastolic pressures in the diagnosis of heart failure with preserved left ventricular systolic function”. I congratulate the authors for their extensive review of literature on the subject.
They discuss the clinical application of the E/E’ ratio “which has been consistently found to be more reproducible in daily practice”. All the papers using spectral tissue Doppler for recording mitral annular velocities have “produced convincing evidence of a positive, linear relation of E/E’ with invasively determined mean LV diastolic pressure regardless of LV ejection fraction, rhythm and heart rate” using conventional statistical method of correlation. But is the data acquisition correct? If not, could these papers be the proof of an ad hoc hypothesis to demonstrate the validity of tissue Doppler?
There are philosophical, methodical and applicational flaws in tissue Doppler[1], so factoring this flawed value to the scientifically valid flow Doppler value would corrupt the latter. In which case, all the correlations produced could be “nonsense” or “spurious” correlations.
Even if we consider the tissue Doppler values as acceptable, what does E/E’ mean? It is the early mitral filling flow velocity divided by early mitral annular tissue relaxation velocity. So what is derived is early mitral flow velocity per unit of mitral annular tissue relaxation velocity. So far, so good. Does this automatically relate to higher left atrial pressures? It is common knowledge that flow Doppler patterns progress from “E/A normal” to “E/A reversal” with higher left atrial pressures. A higher E velocity in “E/A normal” and a lower E in “E/A reversal” goes against this assumption even after dividing with the usual E’ values.
The authors feel the combination of E’ with peak E velocity (i.e., E/E’ ratio) is assumed to “overcome the influence of ventricular relaxation on peak E velocity and reflect left atrial pressure.” The principle may be theoretically correct. It could remove the bias due to different relaxation values in different patients. But what about the application in the same patient? The different points around the mitral annulus ring give different tissue Doppler values. The E value being the same, you will get different E/E’ values. The article agrees to this by stating that “values of >10, >12 and >11 for lateral, septal, and average E/E’, respectively, can be proposed for predicting pulmonary capillary pressure >15 mmHg in the presence of preserved LV systolic function”. So to “overcome the influence of ventricular relaxation on the peak E velocity” multiple values of E’ need to be taken which would be tantamount to introducing a systematic error. Besides, such an exercise (determination of E/E’ ratio) goes against the scientific “principle of parsimony”.
The commonly interrogated medial mitral annulus on 2D apical 4-chamber image has an area of about 0.5 cm2 to 1.5 cm2. In this wide area, where exactly do you place the sample volume? This is considering the fact that the velocities change on minor changes in positioning. Similarly, the medial annulus is common to both the left and right ventricles. How much of an influence the right ventricle has needs to be addressed.
Once again congratulations to the authors for their exhaustive review of literature. In the case of trans-mitral flow Doppler analysis with its inherent complexities we do not need to factor in another variable like E’ and compound the problem. What is required is the application of the Occam’s Razor to derive some meaningful clinical information.[2]
References:
1.Thomas G. Tissue Doppler echocardiography – A case of right tool, wrong use
Cardiovascular Ultrasound 2004, 2:12
2.Thomas G. Classification of transmitral Doppler patterns. Indian Heart J. 2005;57(3):275-6.
Competing interests
No competing interests
Response to the comment by G. Thomas
Stephane Arques, Director of Department of Cardiology, Aubagne Hospital, Aubagne, France
10 April 2007
First, I would like to thank Dr G. Thomas for its attractive comment on the current clinical applications of spectral tissue Doppler echocardiography for the diagnosis of heart failure with preserved left ventricular systolic function (HFPSF). I agree with Dr Thomas on the fact that this method is not “perfect” and that care should be taken before applying it, as reported in the review.
However, currently, what do we need in daily practice for the diagnosis of HFPSF?
We need a simple, reliable and reproducible marker of the severity of myocardial dysfunction for patients who present with symptoms compatible with the diagnosis of heart failure but without obvious left ventricular systolic dysfunction.
Undeniably, the E/E’ ratio fulfills all these criteria since it has been largely validated by numerous, well-recognized research teams not only for the diagnosis of elevated left ventricular filling pressures irrespective of left ventricular systolic function (see the review), but also for the diagnosis of the cardiac contribution to exercise intolerance and acute dyspnea (see the review) and for risk stratification in chronic congestive heart failure regardless of left ventricular ejection fraction [1-5]. Interestingly, most of these studies emphasize the usefulness of E/E’ beyond the analysis of mitral filling.
The “Holy Grail” quest for the “perfect” Doppler-derived marker of left ventricular filling pressures is not over, but currently, I simply recommend the use of spectral tissue Doppler echocardiography as a hallmark for the diagnosis of HFPSF in daily practice.
1.Acil T, Wichter T, Stypmann J, Janssen F, Paul M, Grude M, Schelde HH, Breithardt G, Bruch C: Prognostic value of tissue Doppler imaging in patients with chronic congestive heart failure. Int J Cardiol 2005; 103: 175-181.
2.Dokainish H, Zoghbi WA, Lakkis NM, Ambriz E, Patel R, Quinones MA, Nagueh SF: Incremental predictive power of B-type natriuretic peptide and tissue Doppler echocardiography in the prognosis of patients with congestive heart failure. J Am Coll Cardiol 2005; 45: 1223-1226.
3.Troughton RW, Prior DL, Frampton CL, Nash PJ, Pereira JJ, Martin M, Fogarty A, Morehead AJ, Starling RC, Young JB, Thomas JD, Lauer MS, Klein AL: Usefulness of tissue doppler and color M-mode indexes of left ventricular diastolic function in predicting outcomes in systolic left ventricular heart failure (from the ADEPT study). Am J Cardiol 2005; 96: 257-262.
4.Bruch C, Rothenburger M, Gotzmann M, Sindermann J, Scheld HH, Breithardt G, Wichter T: Risk stratification in chronic heart failure: independent and incremental prognostic value of echocardiography and brain natriuretic peptide and its N-terminal fragment. J Am Soc Echocardiogr 2006; 19: 522-528.
5.Fukuta H, Sane DC, Brucks S, Little WC: Statin therapy may be associated with lower mortality in patients with diastolic heart failure: a preliminary report. Circulation 2005; 112: 357-363.
Is E/E' really reliable?
10 April 2007
I read with great interest the review article “Current clinical applications of spectral tissue Doppler echocardiography (E/E' ratio) as a noninvasive surrogate for left ventricular diastolic pressures in the diagnosis of heart failure with preserved left ventricular systolic function”. I congratulate the authors for their extensive review of literature on the subject.
They discuss the clinical application of the E/E’ ratio “which has been consistently found to be more reproducible in daily practice”. All the papers using spectral tissue Doppler for recording mitral annular velocities have “produced convincing evidence of a positive, linear relation of E/E’ with invasively determined mean LV diastolic pressure regardless of LV ejection fraction, rhythm and heart rate” using conventional statistical method of correlation. But is the data acquisition correct? If not, could these papers be the proof of an ad hoc hypothesis to demonstrate the validity of tissue Doppler?
There are philosophical, methodical and applicational flaws in tissue Doppler[1], so factoring this flawed value to the scientifically valid flow Doppler value would corrupt the latter. In which case, all the correlations produced could be “nonsense” or “spurious” correlations.
Even if we consider the tissue Doppler values as acceptable, what does E/E’ mean? It is the early mitral filling flow velocity divided by early mitral annular tissue relaxation velocity. So what is derived is early mitral flow velocity per unit of mitral annular tissue relaxation velocity. So far, so good. Does this automatically relate to higher left atrial pressures? It is common knowledge that flow Doppler patterns progress from “E/A normal” to “E/A reversal” with higher left atrial pressures. A higher E velocity in “E/A normal” and a lower E in “E/A reversal” goes against this assumption even after dividing with the usual E’ values.
The authors feel the combination of E’ with peak E velocity (i.e., E/E’ ratio) is assumed to “overcome the influence of ventricular relaxation on peak E velocity and reflect left atrial pressure.” The principle may be theoretically correct. It could remove the bias due to different relaxation values in different patients. But what about the application in the same patient? The different points around the mitral annulus ring give different tissue Doppler values. The E value being the same, you will get different E/E’ values. The article agrees to this by stating that “values of >10, >12 and >11 for lateral, septal, and average E/E’, respectively, can be proposed for predicting pulmonary capillary pressure >15 mmHg in the presence of preserved LV systolic function”. So to “overcome the influence of ventricular relaxation on the peak E velocity” multiple values of E’ need to be taken which would be tantamount to introducing a systematic error. Besides, such an exercise (determination of E/E’ ratio) goes against the scientific “principle of parsimony”.
The commonly interrogated medial mitral annulus on 2D apical 4-chamber image has an area of about 0.5 cm2 to 1.5 cm2. In this wide area, where exactly do you place the sample volume? This is considering the fact that the velocities change on minor changes in positioning. Similarly, the medial annulus is common to both the left and right ventricles. How much of an influence the right ventricle has needs to be addressed.
Once again congratulations to the authors for their exhaustive review of literature. In the case of trans-mitral flow Doppler analysis with its inherent complexities we do not need to factor in another variable like E’ and compound the problem. What is required is the application of the Occam’s Razor to derive some meaningful clinical information.[2]
References:
1.Thomas G. Tissue Doppler echocardiography – A case of right tool, wrong use
Cardiovascular Ultrasound 2004, 2:12
2.Thomas G. Classification of transmitral Doppler patterns. Indian Heart J. 2005;57(3):275-6.
Competing interests
No competing interests
Response to the comment by G. Thomas
10 April 2007
First, I would like to thank Dr G. Thomas for its attractive comment on the current clinical applications of spectral tissue Doppler echocardiography for the diagnosis of heart failure with preserved left ventricular systolic function (HFPSF). I agree with Dr Thomas on the fact that this method is not “perfect” and that care should be taken before applying it, as reported in the review.
However, currently, what do we need in daily practice for the diagnosis of HFPSF?
We need a simple, reliable and reproducible marker of the severity of myocardial dysfunction for patients who present with symptoms compatible with the diagnosis of heart failure but without obvious left ventricular systolic dysfunction.
Undeniably, the E/E’ ratio fulfills all these criteria since it has been largely validated by numerous, well-recognized research teams not only for the diagnosis of elevated left ventricular filling pressures irrespective of left ventricular systolic function (see the review), but also for the diagnosis of the cardiac contribution to exercise intolerance and acute dyspnea (see the review) and for risk stratification in chronic congestive heart failure regardless of left ventricular ejection fraction [1-5]. Interestingly, most of these studies emphasize the usefulness of E/E’ beyond the analysis of mitral filling.
The “Holy Grail” quest for the “perfect” Doppler-derived marker of left ventricular filling pressures is not over, but currently, I simply recommend the use of spectral tissue Doppler echocardiography as a hallmark for the diagnosis of HFPSF in daily practice.
1.Acil T, Wichter T, Stypmann J, Janssen F, Paul M, Grude M, Schelde HH, Breithardt G, Bruch C: Prognostic value of tissue Doppler imaging in patients with chronic congestive heart failure. Int J Cardiol 2005; 103: 175-181.
2.Dokainish H, Zoghbi WA, Lakkis NM, Ambriz E, Patel R, Quinones MA, Nagueh SF: Incremental predictive power of B-type natriuretic peptide and tissue Doppler echocardiography in the prognosis of patients with congestive heart failure. J Am Coll Cardiol 2005; 45: 1223-1226.
3.Troughton RW, Prior DL, Frampton CL, Nash PJ, Pereira JJ, Martin M, Fogarty A, Morehead AJ, Starling RC, Young JB, Thomas JD, Lauer MS, Klein AL: Usefulness of tissue doppler and color M-mode indexes of left ventricular diastolic function in predicting outcomes in systolic left ventricular heart failure (from the ADEPT study). Am J Cardiol 2005; 96: 257-262.
4.Bruch C, Rothenburger M, Gotzmann M, Sindermann J, Scheld HH, Breithardt G, Wichter T: Risk stratification in chronic heart failure: independent and incremental prognostic value of echocardiography and brain natriuretic peptide and its N-terminal fragment. J Am Soc Echocardiogr 2006; 19: 522-528.
5.Fukuta H, Sane DC, Brucks S, Little WC: Statin therapy may be associated with lower mortality in patients with diastolic heart failure: a preliminary report. Circulation 2005; 112: 357-363.
Competing interests
No competing interest