Left atrial volumetric/mechanical coupling index in the general population: distribution and prediction of incident atrial fibrillation

Abstract

Abstract Funding Acknowledgements Type of funding sources: Foundation. Main funding source(s): The Copenhagen City Heart Study was funded by the Danish Heart Foundation, and the echocardiographic substudy was further funded by the Lundbeck Foundation. Background Atrial fibrillation (AF) represent a global health burden. Identifying people at risk based on echocardiography has always been challenging. Hence, we aimed to assess the distribution of left atrial volumetric/mechanical coupling index (LACI) in the general population and test its potential to predict incident AF. Methods In a large community-based population study, LACI was calculated by dividing the left atrial (LA) maximal volume by the a’ peak velocity obtained by color Tissue-Doppler Imaging. Clinical endpoint was incident AF. The exclusion criteria were history of AF or previous heart failure. Results A total of 1021 patients formed the study cohort (mean age 52.8 ± 13.3, 45% (n = 459) were male); Median LACI was 2.84 [IQR: 2.14-3.82], rarely exceeding the value of 6. During a follow-up period of 16.1 years (IQR15.6-16.3), 8.9 % (n = 91) of patients developed AF. LACI independently predicted AF (HR 1.11 [1.04-1.17], p = 0.001 unadjusted and HR 1.20 (1.06-1.35), p = 0.003 after a comprehensive multivariable adjustment (including clinical, biochemical, and echocardiographic variables). The Figure illustrates the strong relationship between LACI and the incidence of AF, almost linear, with no plateau effect. In a sensitivity analysis, the association between LACI and incident AF persisted in both hypertensive (HR 1.12 (1.05-1.19) p = 0.001) and non-hypertensive participants (HR 1.18 (1.03-1.35) p = 0.02). Conclusion LACI is a measure of LA function which is routinely available and presents a skewed distribution towards low values in the general population. LACI independently predicts incident AF, irrespective the presence of systemic arterial hypertension. Abstract Figure