Speckle tracking echocardiography(STE) strain indices (peak circumferential strain, peak longitudinal strain and radial strain) allow for an angle and size independent assessment of left ventricular systolic function. Strain parameters measure regional and global myocardial deformation and have also been shown to be a better predictor of future cardiovascular events compared to traditional echo measures of systolic function such as ejection fraction.

Pump parameters such as EF are insensitive for subtle dysfunction and are not contributive in the patients with HFpEF. So quantification of volumes with 3D is useful, but the provided data are not helpful for early detection. 

The best validated and practical measurement is global longitudinal strain, that may reveal early left ventricular dysfunction. Of note, circumferential and radial strain may (diabetes, PMID: 20932716) or may not (obesity, hypertension) decrease in parallel. 

Echo and cardiac MRI can give you best information about Lvef. There was a point in time when it has been said that we will be able to assess lv systolic function by better parameters and Lvef will take a back seat, let us wait and watch. Surely echo is not all about ejection fraction. 

LVEEF estimated by Echo has been emerged as the principal risk stratifier  for the SCD estimation and its protection by an ICD in DCM and post MI patients. However this is mainly an hemodynamic parameter that ignores other  probable coexistent electrical abberations that might exist even when there is mild or non significant LV systolic dysfunction. Whether other Echo derived parameters beyond the LV systolic Dysfunction can contribute to the arrythmia risk prediction in heart failure patients with well preserved LVEF is completelly unknown!

We use routinely most of the time LVEF ( left ventricular ejection fraction) by visual assessement, Simpson Biplane and LVEF by WMSI (wall motion score index). We also use contrast, 3D,strain .  We have performed assessement of LVEF-WMSI by MRI and found very good correlation (ref. Arch.c.v.disease 2012,105,91-98.)

Considering the three first techniques I beleive that LVEF-WMS or WMSI is better than visual because it is a semiquantitative evaluation. It is also better than Simpson biplane because it includes the three planes 2,3  and 4 chambers.

The LVEF-WMSI needs a high quality of image and a compulsive technique to fill up the 16 or 17 segment model using information acquired from the three short axis (base ,mid and apex) and the 3 apicals views (2,3,4Chambers). 

Since strain analysis is also highly dependant on 2D image, high quality 2D images requested by WMSI method could potentially improve quality of strain results.

NB Excelera gives a score for the WMSI with the bull eye informations. You can find the correponding LVEF by Echo or MRI in our articles

Can.j.Cardiol 2003,19,397-404 or www.drlebeau.info.

At present there is no good definition for systolic function. Most authors use the terms global systolic function and ejection fraction synonymously but this may be a mistake. There are many other measures that can be used to assess contractile function including myocardial strain, strain rate, mitral annular displacement and shortening velocities. In heart failure with a normal ejection fraction (HFNEF) there are important abnormalities of these latter (myocardial) measures but the ejection fraction is, by definition, preserved.

The apparent paradox of normal EF with subnormal shortening has led some to make a distinction between the myocardial (or regional) function and the global function (defined by ejection fraction and derived from changes in the lumen). For example some groups have tried to differentiate the muscular pump function from the hemodynamic pump function (despite no explanation for the difference). Others suggest that the abnormalities of systolic function are too subtle to pick up with the ejection fraction. They argue that if the ejection fraction is (nearly) normal then the systolic function must be good therefore HFNEF must be due to diastolic dysfunction. I take an alternative view (Future Cardiol. 2010;6:97-111).

Modelling has shown that the main determinants of ejection fraction are both end-diastolic wall thickness and myocardial strain (Heart. 2008;94:446-449). This explains why in heart failure with a preserved ejection fraction there is wall hypertrophy and a reduced myocardial shortening. In fact there is a mathematical relationship between LV ejection fraction, wall thickness and strain leading to the suggestion that the ejection fraction should be corrected for the wall thickness to give a more meaningful value of function (Euro. J. Echo 2011; 12: 228-34).

In terms of mortality studies EF is excellent post MI but less good in the modern era where approximately 50% of HF patients have a normal EF mainly secondary to hypertensive heart failure. Myocardial strain improves on EF for prognostic assessment in a number of studies (for reviews see below).

The changes in the lumen (EF) must reflect the changes in the myocardium or the laws of physics are broken! The apparent paradox of reduced contractile function and a preserved ejection can be explained by the presence of concentric hypertrophy (or other causes of an increase in wall thickness). This idea underpins some new unifying theories in chronic (Int. J. Cardiol. 2012;154:102-110) and acute heart failure (Int. J. Cardiol. 2013;165:25-34).

Hi, 

The answer by dr. McIver is very interesting, but nevertheless is not exactly what is the present "guidelines" view, based on outcome driven evidence. Nevertheless I like his idea of correcting endocardial function for wall thickness. 

What however is underpinned by the same idea but is better validated, is the analysis of midwall function according to Shimuzu. This was shown to be independently predictive of events in the LiFE study and still its additional value over and above LV mass and BP. 

I put enclosed a lecture given last week at the ESC. I carefully reproduced in these slides what is written in the coming Recommendations for the echo evaluation of the patient with hypertension (JASE and EJCVI to be in press soon). 

Interesting question and impressive answers. Thanks much @ Thierry for the article.

WMSEF a 5second equivalent 3D evaluation

I would like to discuss  wall motion score left ventricular ejection fraction  (WMSEF) with regard to two articles published in the JASE September and October 2014.The first article is an expert consensus statement on evaluation of adult cancer therapy  (JASE 2014 ;27:911-939). One of the key point with regards to 2D echocardiography is that the modified biplane  Simpson's technique is the method of choice to asses LVEF and should be combined with the calculation of WMSI.

The second article by M. Aurich " Assessment of  LV volume with echocardiography and CMR : real life evaluation of standard semiautomatic method" (JASE  2014 ; 27:1017-1024). The authors state that biplane Simpson EF depend on accurate manual border tracing which is done on a 2D frozen image which could be challenging and time consuming when image are of poor quality. Automatic EF is not the best technique for suboptimal images. In his editorial comments, Dr Muroni insists, "adequate image quality is critical perequisite for any border tracing algorythm either 2D or 3D semiautomatic or automatic".

In 2D echo, two major pitfalls are the foreshortened apical views and when 2 segments are not visible. We do not have these pitfalls with WMS because the 4 apicals segments of the bull eye are specifically analysed and reported and we can extrapolate any difficult segments using the information from the apical views (2,3 and 4 Chambers). The WMSEF is not dependant  of  volume calculation.

I would like to propose a challenge for your fellows or technicians : use WMSEF in ten patients and gave me a feedback. Thumb up ,thumb down or good result compare to what you use in your routine exam 2D Simpson, 3D,  automatic EF, Nuclear medicine or MRI. The goal of this letter is not to replace any of these technique that have been  clearly validated but to bring another player a fast and simple one, into the game (5 sedcond calculation).

WMSEF exist since 1990 and numerous articles had been published on this subject it is generally not use because it ask a compulsive evaluation of  the 16  segments of the polar map. The industries try to compensate the need of working for good images whit automatic technique that in my point of view are not as valuable as an excellent WMS evaluation that you need anyway in these automatic technique.

P.S.: A true revolution in echo machine would be the possibility to have the 3 classical short axis from apical views like we obtain by passing electroncally the 2C from the 4C rather than the blurry reconstruction achieve by 3D.

REF 1- " A new tool for estimating LVEF derived from WMSI" . Can J Cardiol. 2003 ;19 : 397-404

2-"Assessment of LVEF by WMSI in MRI" Arch.of CV disease 2012 ; 105, 91-98

3-WWW: drlebeau.info