Abstract Body (Do not enter title and authors here): Introduction: Left atrial (LA) strain is associated with important outcomes including atrial fibrillation, stroke, dementia, and heart failure. Several individual cardiovascular (CV) risk factors are associated with LA strain, but there is limited knowledge about the relationship of a comprehensive CV health (CVH) assessment and LA strain. Moreover, it is unknown if change in CVH impacts LA strain.

Hypothesis: Low or declining CVH is associated with reduced LA function.

Methods: Using data from the Atherosclerosis Risk in Communities (ARIC) study we characterized CVH at midlife (Visit 2: 1990-92) and late-life (Visit 5: 2011-13) using the American Heart Association’s Life’s Essential 8 (LE8) score. LE8 scores were categorized into low (0-49), moderate (50-79), and high (80-100) CVH. Participants were assigned to one of four categories based on change in CVH over time: 1. healthy/improving – high V5 CVH; 2. healthy/slow decline – high CVH at V2 and moderate at V5; 3. moderate – low or moderate CVH at V2 and moderate at V5; and 4. low/declining – low CVH at V5. The primary outcome was LA strain (reservoir and conduit) measured by echocardiography at V5. Linear regression was used to evaluate the association of the four CVH groups and LA strain values and logistic regression was used to evaluate the association of CVH with abnormal LA reservoir strain defined as <28.9%. Models were adjusted for age, sex, and race/center.

Results: This analysis included 4,766 participants free of CVD at V2. Their mean (SD) age was 54.8 (5.0) years at V2 and 75.5 (5.1) years at V5; 41% male and 19% Black. Totals in each CVH subgroup were 362 healthy/improving, 718 healthy/slow decline, 2,780 moderate, and 906 low/declining. Moderate or declining CVH was associated with worse LA reservoir and conduit strain compared to those with high CVH (Figure). Abnormal LA reservoir strain was nearly twice as likely among those with low/declining CVH compared to the healthy/improving group (OR 1.98, 95% CI 1.51-2.61).

Conclusion: Establishing and maintaining high CVH in midlife may prevent development of LA dysfunction, an early marker of CVD. Future studies could test interventions that improve overall CVH using change in LA strain as an outcome.