Clinical Applications of Speckle-Tracking Echocardiography in Heart Failure: From Diagnosis to Prognostication.

Speckle-tracking echocardiography (STE) has emerged as a valuable noninvasive tool for assessing myocardial deformation in patients with heart failure (HF). This review summarizes the principles, clinical applications, and prognostic implications of strain echocardiography across the spectrum of HF phenotypes, including heart failure with reduced ejection fraction (HFrEF), mildly reduced ejection fraction (HFmrEF), and preserved ejection fraction (HFpEF). Global longitudinal strain (GLS) provides a more sensitive and reproducible measure of left ventricular (LV) systolic function than traditional echocardiographic parameter like LV ejection fraction (EF), enabling early detection of subclinical dysfunction in stage A and B HF. In HFrEF, LVGLS adds incremental prognostic value beyond LVEF and identifies patients at risk for adverse outcomes. In HFmrEF, it helps characterize disease trajectory, guide therapy, and predict LVEF deterioration. In HFpEF, LVGLS uncovers subtle systolic impairment and stratifies risk. Additionally, left atrial (LA) and right ventricular (RV) strain measurements are increasingly recognized as important indicators of chamber-specific dysfunction and predictors of mortality, HF hospitalization, and atrial fibrillation. Despite vendor variability and the lack of universally accepted cut-offs, STE is becoming integral to HF evaluation. Pattern recognition of myocardial strains, such as apical sparing in amyloidosis, adds diagnostic value in cardiomyopathies. The integration of strain parameters enhances risk stratification, facilitates early diagnosis, and aids therapeutic monitoring in HF. Further standardization and broader clinical adoption of STE are needed to fully harness its prognostic and diagnostic capabilities in HF management.