Association of Left Atrial Structure and Function With Heart Failure in Older Adults.

Background: Limited data exist to characterize novel measures of left atrial (LA) structure and function in older adults without prevalent heart failure (HF).

Objectives: The aim was to assess reference range of LA measures, their associations with N-terminal pro-B-type natriuretic-peptide (NT-proBNP) and the related risk for incident HF or death.

Methods: We analyzed LA structure (LA maximal [LAViMax] and minimal volume indexed by body surface area) and function (LA emptying fraction, LA reservoir, conduit, and contraction strain) in 4,901 participants from the ARIC (Atherosclerosis Risk In Communities) study (mean age 75 ± 5 years, 40% male, and 19% Black) without prevalent HF. We assessed sex-specific 10th and 90th percentile ARIC-based reference limits in 301 participants free of prevalent cardiovascular disease, and related LA measures to NT-proBNP and incident HF or death (median follow-up of 5.5 years) in the whole ARIC cohort.

Results: Approximately 20% of the overall population had LA abnormalities according to the ARIC-based reference limit. Each LA measure was associated with NT-proBNP and, except for LAViMax, with incident HF or death after multivariable adjustment (including left ventricular function and NT-proBNP). Results were consistent in participants with normal LAViMax (P for interaction > 0.05). LA measures were prognostic for both incident HF with preserved ejection fraction or death and incident HF with reduced ejection fraction or death. When added to HF risk factors and NT-proBNP (baseline C-statistics = 0.74) all LA measures, except for LAViMax, significantly enhanced the prognostic accuracy.

Conclusions: Novel measures of LA structure and function, but not standard assessment by LAViMax, are associated with increased risk of incident HF or death regardless of measures of left ventricular function and NT-proBNP.