Left Atrial Reservoir Strain as a Marker of Carotid Vascular Remodeling: Insights Into the Atrial-Vascular Aging Continuum.

BACKGROUND: Left atrial reservoir strain (LASr) has emerged as a sensitive marker of subclinical cardiac dysfunction and has been proposed as an early indicator of cardiovascular aging. However, whether impaired LASr reflects the progressive spectrum of carotid vascular aging has not been fully established. AIMS: To evaluate the association between LASr and different stages of carotid vascular aging and to determine its ability to identify advanced carotid vascular disease in adults undergoing comprehensive cardiovascular imaging. DESIGN: Retrospective, single-center, observational cross-sectional study. METHODS: A total of 1475 consecutive adults who underwent transthoracic echocardiography and carotid ultrasonography were included. Participants were categorized into three predefined carotid vascular aging stages according to carotid ultrasonographic findings. LASr was assessed using two-dimensional speckle-tracking echocardiography. Multivariable ordinal logistic regression and receiver operating characteristic analyses were performed. RESULTS: Of the 1475 participants, 628 (42.6%) were classified as Stage 0, 391 (26.5%) as Stage 1, and 456 (30.9%) as Stage 2. LASr progressively declined across carotid vascular aging stages (39.4 ± 6.3%, 34.7 ± 5.8%, and 28.9 ± 6.1%, respectively; p < 0.001). LASr demonstrated a significant inverse correlation with carotid intima-media thickness (r = -0.56, p < 0.001). After multivariable adjustment, lower LASr remained independently associated with progressive carotid vascular aging (adjusted OR per 1% decrease: 1.09, 95% CI 1.06-1.12; p < 0.001). LASr identified carotid plaque with an area under the curve of 0.823 (95% CI 0.801-0.845), with an optimal cutoff value of 31.8% (sensitivity 80.5%, specificity 71.2%). CONCLUSION: Left atrial reservoir strain progressively declined across increasing categories of carotid structural remodeling and remained independently associated with carotid vascular abnormalities after adjustment for conventional cardiovascular risk factors and echocardiographic parameters. Furthermore, LASr provided incremental discriminatory information for identifying carotid plaque beyond a predefined clinical model. These findings suggest that LASr may serve as a complementary myocardial marker of subclinical carotid vascular remodeling, although its broader role as a marker of systemic cardiovascular aging requires further longitudinal validation.