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Tissue tracking technologies such as speckle tracking echocardiography and feature tracking cardiac magnetic resonance have enhanced the noninvasive assessment of myocardial deformation in clinical research and clinical practice. The widespread enthusiasm for using tissue tracking techniques in research and clinical practice stems from the ready applicability of these technologies to routine echocardiographic or cardiac magnetic resonance images. The technology is common to both modalities, and derived parameters to describe myocardial mechanics are the similar, albeit with different accuracies. We provide an overview of the normal values and reproducibility of the clinically applicable parameters, together with their clinical validation. The use of these technologies in different clinical scenarios, and the additive value to current imaging diagnostics are discussed.

Fully automated analysis of echocardiography images provides rapid and reproducible assessment of left ventricular EF and LS.

Tracking deformation of the left-sided cardiac chambers from routine cardiac ultrasound images provides accurate information for Doppler-independent phenotypic characterization of LV diastolic function and noninvasive assessment of LV filling pressures.

Echocardiography, given its safety, easy availability, and the ability to permit a comprehensive assessment of cardiac structure and function, is an indispensable tool in the evaluation and management of patients with heart failure (HF). From initial phenotyping and risk stratification to providing vital data for guiding therapeutic decision-making and monitoring, echocardiography plays a pivotal role in the care of HF patients. The recent advent of multiparametric approaches for myocardial deformation imaging has provided valuable insights in the pathogenesis of HF, elucidating distinct patterns of myocardial dysfunction and events that are associated with progression from subclinical stage to overt HF. At the same time, miniaturization of echocardiography has further expanded clinical application of echocardiography, with the use of pocket cardiac ultrasound as an adjunct to physical examination demonstrated to improve diagnostic accuracy and risk stratification. Furthermore, ongoing advances in the field of big data analytics promise to create an exciting opportunity to operationalize precision medicine as the new approach to healthcare delivery that aims to individualize patient care by integrating data extracted from clinical, laboratory, echocardiographic, and genetic assessments. evidence supporting the diagnosis of HF. Echocardiography is the most commonly used modality for this purpose because of its ease of application, noninvasive nature, safety, and ability to provide a vast amount of information about cardiac structure and function. Additionally, echocardiography also plays an important role in guiding therapeutic decision-making and in monitoring response to therapy. Over the past 3 decades, numerous advancements have occurred in the field of echocardiography that have helped improve our understanding of the morpho-functional aberrations occurring in HF. This review summarizes the recent advances in echocardiography as applicable to the evaluation and management of HF. Classification of Heart FailureTo facilitate clinical management, several attempts have been made to divide HF patients into categories that unify them according to their dominant clinical presentations. Thus, HF has often been described as low output failure or high output failure; forward failure or backward failure; systolic HF or diastolic HF; HFrEF or HF with preserved ejection fraction (HFpEF); and so on. More recently, HF has also been classified according to alterations in the mechanical function of the left ventricle (LV; Table 1). 6The classification of HF into systolic or diastolic HF appeared to be intuitive, categorizing patients based on the primary pathogenic abnormality, that is, impairment of cardiac contractility or impairment of filling. However, this description has now been abandoned with the recognition that these 2 entities are not mutually exclusive and have considerable overlap. Significant LV diastolic dysfunction is a ubiquitous occurrence in patients with systolic HF, whereas systolic dysfunction...

An unsupervised assessment of echocardiographic variables for assessing LV DD revealed unique patterns of grouping. These natural patterns of clustering may better identify patient groups who have similar risk, and their incorporation into clinical practice may help eliminate indeterminate results and improve clinical outcome prediction.

A 52-year-old white man visited his physician because he started experiencing shortness of breath on walking short distances at ground level. He had smoked half a packet of cigarettes daily for 40 years. Physical examination revealed a blood pressure of 147/95 mm Hg. Chest examination and chest x-ray were unremarkable, and ECG showed left atrial abnormality. The patient had normal serum electrolytes, blood sugar, and kidney function tests. A stress echocardiogram was ordered to exclude potential coronary artery disease. His resting echocardiography showed an ejection fraction (EF) of 60%, normal septal and posterior wall thickness, and mild diastolic dysfunction (septal early diastolic mitral annular velocity [e′] of 7 cm/s, early diastolic [E wave] to late diastolic [A wave] transmitral Doppler flow velocity ratio [E/A] of 1.4, E-wave deceleration time of 210 ms, E/e′ ratio of 9, and left atrial volume index of 44 mL/m 2 ; Figure 1A). There were no resting segmental wall motion abnormalities suggestive of ischemia. The patient exercised on a treadmill using Bruce protocol for 4 minutes and 43 s, and achieved 6.6 metabolic equivalent of task and maximum heart rate of 148 bpm (88% of his maximum age predicted heart rate). At peak exercise, the patient developed severe dyspnea and his blood pressure was 213/90 mm Hg. Post exercise echocardiography was acquired within 1 minute of exercise termination and showed EF of 69% and no segmental wall motion abnormalities, with Doppler recordings obtained at recovering heart rate of 125 bpm; showing a septal e′ velocity of 7.3 cm/s, E/A of 1.9, E-wave deceleration time of 110 ms, and E/e′ of 13.7, left atrial volume index of 35 mL/m 2 ( Figure 1B). Ten minutes into the recovery period, the blood pressure returned to basal level (145/80 mm Hg). Compared with resting levels, the increased E/A ratio, shortened E-wave deceleration time and relatively increased E/e′ ratio suggested post exercise worsening of diastolic function with elevation of left ventricular (LV) filling pressures. To investigate the mechanistic basis of diastolic dysfunction in this patient, LV deformation was assessed offline using speckletracking echocardiography (STE). Besides characterizing the longitudinal and circumferential shortening, and radial thickening, the LV rotational deformation, that resembles the wringing of a towel, was also measured (Figures 2 and 3). This wringing deformation, also referred to as LV twist (LVT) and the subsequent recoil that occurs in diastole, referred to as untwist, were abnormal in this patient (Figure 4). At rest, the patient had mild diastolic dysfunction, which was associated with a higher than normal LVT and untwist values, compared with the published age-related normal values, 1,2 and low global longitudinal strain. At peak exercise, there was a significant worsening of the patient's diastolic parameters, which was associated with worsening untwist values and further reduction of global longitudinal strain, whereas LVT remained same in magnitude. The following ...

BackgroundWe have previously reported strain dyssynchrony index assessed by two-dimensional speckle tracking strain, and a marker of both dyssynchrony and residual myocardial contractility, can predict response to cardiac resynchronization therapy (CRT). A newly developed three-dimensional (3-D) speckle tracking system can quantify endocardial area change ratio (area strain), which coupled with the factors of both longitudinal and circumferential strain, from all 16 standard left ventricular (LV) segments using complete 3-D pyramidal datasets. Our objective was to test the hypothesis that strain dyssynchrony index using area tracking (ASDI) can quantify dyssynchrony and predict response to CRT.MethodsWe studied 14 heart failure patients with ejection fraction of 27 ± 7% (all≤35%) and QRS duration of 172 ± 30 ms (all≥120 ms) who underwent CRT. Echocardiography was performed before and 6-month after CRT. ASDI was calculated as the average difference between peak and end-systolic area strain of LV endocardium obtained from 3-D speckle tracking imaging using 16 segments. Conventional dyssynchrony measures were assessed by interventricular mechanical delay, Yu Index, and two-dimensional radial dyssynchrony by speckle-tracking strain. Response was defined as a ≥15% decrease in LV end-systolic volume 6-month after CRT.ResultsASDI ≥ 3.8% was the best predictor of response to CRT with a sensitivity of 78%, specificity of 100% and area under the curve (AUC) of 0.93 (p < 0.001). Two-dimensional radial dyssynchrony determined by speckle-tracking strain was also predictive of response to CRT with an AUC of 0.82 (p < 0.005). Interestingly, ASDI ≥ 3.8% was associated with the highest incidence of echocardiographic improvement after CRT with a response rate of 100% (7/7), and baseline ASDI correlated with reduction of LV end-systolic volume following CRT (r = 0.80, p < 0.001).ConclusionsASDI can predict responders and LV reverse remodeling following CRT. This novel index using the 3-D speckle tracking system, which shows circumferential and longitudinal LV dyssynchrony and residual endocardial contractility, may thus have clinical significance for CRT patients.