Echocardiographic Strain Analysis Research Articles

Assessing left ventricular systolic dysfunction after myocardial infarction: are ejection fraction and dP/dtmax complementary or redundant?

Among the various cardiac contractility parameters, left ventricular (LV) ejection fraction (EF) and maximum dP/dt (dP/dt(max)) are the simplest and most used. However, these parameters are often reported together, and it is not clear if they are complementary or redundant. We sought to compare the discriminative value of EF and dP/dt(max) in assessing systolic dysfunction after myocardial infarction (MI) in swine. A total of 220 measurements were obtained. All measurements included LV volumes and EF analysis by left ventriculography, invasive ventricular pressure tracings, and echocardiography. Baseline measurements were performed in 132 pigs, and 88 measurements were obtained at different time points after MI creation. Receiver operator characteristic (ROC) curves to distinguish the presence or absence of an MI revealed a good predictive value for EF [area under the curve (AUC): 0.998] but not by dP/dt(max) (AUC: 0.69, P < 0.001 vs. EF). Dividing dP/dt(max) by LV end-diastolic pressure and heart rate (HR) significantly increased the AUC to 0.87 (P < 0.001 vs. dP/dt(max) and P < 0.001 vs. EF). In naïve pigs, the coefficient of variation of dP/dt(max) was twice than that of EF (22.5% vs. 9.5%, respectively). Furthermore, in n = 19 pigs, dP/dt(max) increased after MI. However, echocardiographic strain analysis of 23 pigs with EF ranging only from 36% to 40% after MI revealed significant correlations between dP/dt(max) and strain parameters in the noninfarcted area (circumferential strain: r = 0.42, P = 0.05; radial strain: r = 0.71, P < 0.001). In conclusion, EF is a more accurate measure of systolic dysfunction than dP/dt(max) in a swine model of MI. Despite the variability of dP/dt(max) both in naïve pigs and after MI, it may sensitively reflect the small changes of myocardial contractility.

Abstract 17744: Impact of Hypertensive Crisis on Left Ventricular Systolic and Diastolic Function: Comprehensive Speckle Tracking Strain Analysis vs. Conventional Echocardiography

Introduction: Echocardiographic strain analysis using speckle tracking is more sensitive than traditional 2-D &amp; Doppler evaluation. The acute impact of hypertensive crisis on LV systolic and diastolic function using echocardiography is not described. Hypothesis: Hypertensive crisis induces acute impairment of LV systolic &amp; diastolic function that may be detected using strain analysis. Methods: Thirty consecutive patients with hypertensive crisis underwent serial echocardiograms including 2D, Doppler &amp; Speckle Tracking strain analyses at baseline &amp; after blood pressure optimization. Results: Mean age of the patients was 53.9 ± 12.8 yrs. Most common presenting symptoms were shortness of breath (70%), chest pain (43.3%), &amp; altered mental status (13.3%). Mean systolic &amp; diastolic blood pressures at baseline were 193.5 ± 25.1mmHg and 106.8 ± 19.8mmHg that reduced to 142.8 ± 20.5mmHg (p&lt;0.001) and 76.7 ± 18.4mmHg (p&lt;0.001) respectively after therapy.Baseline and follow-up echocardiograms showed reduction in left and right atrial volumes at follow-up. There was no change in LV ejection fraction &amp; fractional shortening at follow-up (48.5 ± 18.2 % vs. 46.7 ± 18.3 %; p=0.50 and 28.0 ± 15.2 % vs. 30.8 ± 14.4 %; p=0.22 respectively). Doppler trans-mitral E-wave and A-wave velocities &amp; mitral E/A ratio were similar at baseline and follow-up.There was an increase in mean global longitudinal LV systolic strain (-10.4 ± 4.4 % to -12.1 ± 4.2 %; p=0.011). Peak systolic circumferential strain increased on follow-up from -6.0 ± 3.2 to -11.3 ± 5.4, p=0.03.Mean global early diastolic strain increased from -4.9 ± 2.7 to -9.4 ± 5.0, p=0.05 at follow-up. Conclusions: Our study describes the impact of hypertensive crisis on echocardipgrahic parameters of LV systolic and diastolic function using strain analysis that has never been described before. Global longitudinal &amp; circumferential systolic strain are more sensitive at detecting subtle changes in LV systolic function in the setting of hypertensive crisis when compared to ejection fraction and fractional shortening. Echocardiographic indices of LV diastolic function (E/e', Left atrial volume and mitral DT) as well as early diastolic strain also significantly improve after therapy.

In This Issue

HomeCirculation ResearchVol. 108, No. 8In This Issue Free AccessIn BriefPDF/EPUBAboutView PDFView EPUBSections ToolsAdd to favoritesDownload citationsTrack citationsPermissions ShareShare onFacebookTwitterLinked InMendeleyReddit Jump toFree AccessIn BriefPDF/EPUBIn This Issue Originally published15 Apr 2011https://doi.org/10.1161/RES.0b013e31821bc2c3Circulation Research. 2011;108:899Echocardiographic Strain Analysis in Mice (p 908)A new echocardiographic technique for mice provides a better picture of heart function, report Bauer et al.Download figureDownload PowerPointThe standard procedure for assessing cardiac function in vivo is echocardiography, but this technique has limited resolution in humans, let alone small-model organisms like mice. Recently, two techniques have been developed to improve the accuracy of echocardiographic imaging in humans: strain analysis, which measures the change in size of particular heart regions, and speckle-tracking, in which specific small features (speckles) are tracked from frame to frame to improve the accuracy of strain measurements. Together, these techniques could also offer a feasible approach for accurate cardiac functional analysis in mice. To test this, Bauer et al induced heart attacks in adult mice and then measured cardiac function using the new techniques. Left ventricular measurements were considerably more sensitive using speckle-tracking strain analysis than standard echocardiography. Furthermore, the new techniques could detect subtle improvements following therapy as soon as two weeks after treatment; whereas standard echocardiography did not detect improvement even after six weeks. The ability to quickly and accurately measure cardiac function in mice will enable not only accurate assessment of new cardiac therapies, but also detection of subtle phenotypic differences between genetic model strains.Hand2 Plays a Novel Role in Epicardiogenesis (p 940)Barnes et al have uncovered a new role in cardiogenesis for the transcription factor, Hand2.Download figureDownload PowerPointHand1 and Hand2 are critical transcription factors for the correct development of the vertebrate heart. The two related factors are largely responsible for the morphogenesis of separate tissues and structures in the heart and only partially overlap in their expression pattern. Indeed, although mouse knockouts of either factor both die at around day 9.5 of embryogenesis, they display factor-specific tissue defects. Barnes et al were most interested in the heart cells in which Hand1 and −2 expressions do overlap. They devised a Hand1-specific Hand2 knockout—that is, the knockout of Hand2 only occurred in cells expressing Hand1. Importantly, these embryos survived until day 14.5 of embryogenesis, allowing Hand2's role to be assessed later in development. Mice with this conditional knockout failed to develop a proper epicardium and coronary vasculature (which is formed, in part, from epicardial cells). This role in epicardial development was hitherto unknown for Hand2. Given Hand1's and −2's essential role in cardiogenesis, the two factors and their pathways are implicated as mediators of congenital heart disease. The study by Barnes et al thus offers further insight into the factors' normal functions in cardiogenesis and possible ways the process could go wrong.Atherosclerotic Plaque Alternative Macrophages (p 985)Chinetti-Gbaguidi et al identify a population of macrophage do-gooders at atherosclerotic plaques.Download figureDownload PowerPointAs part of the pathologic process of atherosclerosis, monocytes infiltrate the plaque and develop into specialized fat-filled macrophages, called foam cells. Although foam cells are not problematic individually, their accumulation is detrimental, and it contributes to plaque growth and local inflammation. Monocyte-to-macrophage development can occur by both classic and alternative pathways. Classic activation produces M1 macrophages, which are known to be capable of developing into foam cells. Alternative activation produces M2 macrophages, which have also been found at plaques, though their function there was unknown. Chinetti-Gbaguidi et al discovered that M2 cells at atherosclerotic plaques had far less proclivity for foam cell formation and contained far less fat. Instead, their main occupation seemed to be phagocytosis—they gobbled up more apoptotic cells and debris than their M1 counterparts. Unlike M1 cells, M2 cells are known to produce antiinflammatory signals. Thus, the presence of these antiinflammatory, foam cell-resistant, phagocytosing M2 macrophages at atherosclerotic plaques could well be beneficial. Perhaps boosting their numbers may be a therapeutic avenue worth investigating.Written by Ruth Williams Previous Back to top Next FiguresReferencesRelatedDetails April 15, 2011Vol 108, Issue 8 Advertisement Article InformationMetrics © 2011 American Heart Association, Inc.https://doi.org/10.1161/RES.0b013e31821bc2c3 Originally publishedApril 15, 2011 PDF download Advertisement

Atrial asynchrony and function before and after electrical cardioversion for persistent atrial fibrillation

The relation between left atrial (LA) electrical and mechanical activity is a challenging field of investigation. The availability of echocardiographic strain analysis techniques has enhanced our ability to non-invasively assess LA wall mechanical synchrony and performance. The aim of our study was to investigate how new strain analysis tools describe the improvement in LA mechanical function after sinus rhythm (SR) restoration as a result of electrical cardioversion (CV) and how such improvement mirrors endocrine profile changes. Seventy-three patients, with persistent atrial fibrillation (AF) who underwent successful electrical CV, were prospectively studied with transthoracic echocardiography 1 week before CV and 1 month after SR. Speckle-tracking 2D-strain evaluation and asynchrony quantification were performed according to the standard deviation of time-to-peak (TP-SD) of deformation of six segments automatically located along the perimeter of the LA cavity, as imaged in an apical four-chamber view. We also calculated classic echocardiograhic parameters such as mitral regurgitation (MR) jet area, LA volume, LV diastolic and systolic volumes, as well as E-wave velocity and deceleration time (DT) on transmitral pulsed wave Doppler. Specimens for plasmatic brain natriuretic peptide (BNP) were also obtained before and 1 month after CV. After 1 month of SR, we detected a significant reduction in TP-SD (from 17.5 +/- 7.4 to 15.2 +/- 7.5%, P = 0.022), this being the expression of improved LA asynchrony, together with a marked increase in LA deformation (peak strain from 11.4 +/- 5.2 to 17.2 +/- 7.5%, P < 0.001) and a reduction in LA volume (-4.5 +/- 36%, P = 0.012). BNP decreased by one-third (from 127 +/- 96 to 86 +/- 89 pg/mL, P = 0.01). We also noticed improved ventricular pump performance [LV ejection fraction (EF) from 53 +/- 10 to 57 +/- 8%, P = <0.001] due to a 20 +/- 42% (P < 0.001) increase in LV diastolic volume (without variations in LV systolic volume and mass), a better diastolic profile (DT 34 +/- 64%, P = 0.003), and a reduction in MR jet area (-1.0 +/- 2.0 cm(2), P < 0.001). These findings are compatible with reverse LA remodelling secondary to SR maintenance, with a favourable effect on LV function that appears modulated by the atrium itself. A significant correlation (r = 0.40, P < 0.001) was demonstrated between TP-SD and peak strain data pre-post CV. At multivariate analysis, a significant capacity for the TP-SD/peak strain ratio to predict AF recurrence at 1-year follow-up (P = 0.013) was shown. Our novel noninvasive approach appears to be able to describe the LA mechanical behaviour during AF and how this ameliorates after 1 month of SR, together with an improved endocrine profile. LA mechanical data pre-CV can predict AF recurrence 1-year post CV.

The meaning of the normal

This study aims at understanding left ventricular (LV) mechanics of non-compaction (LVNC) phenotype using echocardiographic strain analysis and at assessing the association of functional parameters with cardiovascular (CV) outcomes.Longitudinal (GLS) and circumferential strain (GCS) as well as rotation of the LV were analyzed in 55 LVNC patients and 55 matched controls. Cardiovascular outcomes were documented for a median follow-up duration of 6 years. GLS and GCS were impaired in LVNC. Similary, regional longitudinal and circumferential strain as well as twist were reduced. CV events occurred in 28 LVNC patients. Apical peak circumferential strain (APCS), peak systolic rotation of apical segments (APSR), and twist were strongly associated with events. This was independent of and incremental to LVEF and non-compacted to compacted myocardial thickness ratio (NC:C ratio). The association of twist with events was also independent of and slightly superior to GLS.GLS, GCS, regional strain, and twist were impaired in LVNC. APCS, APSR, and twist exhibited strong association with CV events independent of and incremental to LVEF and NC:C ratio, and in case of twist even GLS. Thus, STE-derived parameters may complement the echocardiographic assessment of LVNC patients in clinical routine.