Left Atrial Strain as a Potential, Promising Tool for Early Detection and Evaluation of Cardiovascular Diseases: A Comprehensive Review

Cardiovascular diseases remain the leading cause of morbidity and mortality worldwide, with cardioembolic events accounting for a substantial proportion of adverse outcomes. Left atrial strain (LAS), particularly left atrial reservoir strain (LASr), has recently been incorporated into contemporary guideline‐based assessment of left ventricular diastolic function, representing its only established routine clinical application. Beyond this role, accumulating evidence identifies LAS as a sensitive marker of atrial mechanical dysfunction, capturing early alterations in reservoir, conduit, and contractile function. Reduced LAS is consistently associated with elevated left ventricular filling pressures and with increased risks of ischemic stroke, atrial fibrillation, adverse cardiac remodeling, and heart failure. These observations position LAS as a promising tool for refined risk stratification, early disease detection, and prognostic evaluation across a broad spectrum of cardiovascular conditions. However, outside diastolic function assessment, these applications remain investigational and are not yet validated for routine clinical use. Ongoing advances in speckle‐tracking echocardiography, multimodality imaging, and artificial intelligence are expected to enhance the reproducibility and clinical integration of LAS. This paper provides a comprehensive review of the emerging role of LAS as a potential noninvasive sensitive biomarker for the early detection, risk evaluation, prognostic assessment, and therapeutic guidance of major cardiovascular events, specifically cardioembolic strokes, heart failure, cardiomyopathies, and coronary artery diseases. Abbreviations: ACM or AtCM, atrial cardiomyopathy; ACS, acute coronary syndrome; AF, atrial fibrillation; AI, artificial intelligence; ARVC, arrhythmogenic right ventricular cardiomyopathy; AUC, area under the curve; BMI, body mass index; CA, cardiac amyloidosis; CAD, coronary artery disease; CCT, cardiac computed tomography; CCTA, cardiac computed tomography angiography; CHF, congestive heart failure; CIS, cryptogenic ischemic stroke; CKD, chronic kidney disease; CMR, cardiac magnetic resonance; CRP, C‐reactive protein; CRT, cardiac resynchronization therapy; CS, cryptogenic stroke; DCM, dilated cardiomyopathy; EAT, epicardial adipose tissue; ECG, electrocardiogram; ESE, exercise stress echocardiography; ESUS, embolic strokes of undetermined source; HCM, hypertrophic cardiomyopathy; HF, heart failure; HFpEF, heart failure with preserved ejection fraction; HR, heart rate; HTN, hypertension; ILs, interleukins; LA, left atrial; LAA, left atrial appendage; LAA MD, Left atrial appendage mechanical dispersion; LACI, LA coupling index; LACM, left atrial cardiomyopathy; LAEF, LA emptying fraction; LAGLS, reduced left atrial global longitudinal strain; LAS, left atrial strain; LAScd, LA strain conduit; LASct, LA contractile strain; LASr, Left atrial reservoir strain; LASTI, left atrial strain time integral; LAVI, left atrial volume index; LAViH 2 , LA volume indexed to height 2 ; LAVImin, the LA minimum volume index; LBBB, left bundle branch block; LGE, late Gadolinium enhancement; LV, left ventricular; LVAs, low‐voltage areas; LVDD, left ventricular diastolic dysfunction; LVEDD, left ventricular end‐diastolic diameter; LVEF, left ventricular ejection fraction; LVH, left ventricular hypertrophy; MACE, major adverse cardiovascular events; METs, metabolic equivalents; MPO, myeloperoxidase; NOHCM, nonobstructive HCM; NOS, nitric oxide synthase; Nox, NADPH oxidase; NT‐proBNP, N‐terminal‐pro brain natriuretic peptide; PALS, peak atrial longitudinal strain; PTFV1, P‐terminal force in lead V1; PVI, pulmonary vein isolation; RA, right atrial; RASr, lower RA reservoir strain; RCM, restrictive cardiomyopathy; ROI, region of interest; ROS, reactive oxidant species; SCD, sudden cardiac death; SEC, spontaneous echo contrast; STE, speckle tracking echocardiography; STEMI, ST‐elevation myocardial infarction; TAC, transverse aortic constriction; TAVI, transcatheter aortic valve implantation; TNF‐α, tumor necrosis factor‐alpha; vWf, von Willebrand factor; WMH, white matter hyperintensities. Mohamad Al Qassab, Christopher Sleiman these authors contributed equally.