Change in left atrial function predicts incident atrial fibrillation: the Multi-Ethnic Study of Atherosclerosis

Abstract

Aims Longitudinal change in left atrial (LA) structure and function could be helpful in predicting risk for incident atrial fibrillation (AF). We used cardiac magnetic resonance (CMR) imaging to explore the relationship between change in LA structure and function and incident AF in a multi-ethnic population free of clinical cardiovascular disease at baseline. Methods and results In the Multi-Ethnic Study of Atherosclerosis (MESA), 2338 participants, free at baseline of clinically recognized AF and cardiovascular disease, had LA volume and function assessed with CMR imaging, at baseline (2000–02), and at Exam 4 (2005–07) or 5 (2010–12). Free of AF, 124 participants developed AF over 3.8 ± 0.9 years (2015) following the second imaging. In adjusted Cox regression models, an average annualized change in all LA parameters were significantly associated with an increased risk of AF. An annual decrease of 1-SD unit in total LA emptying fractions (LAEF) was most strongly associated with risk of AF after adjusting for clinical risk factors for AF, baseline LA parameters, and left ventricular mass-to-volume ratio (hazard ratio per SD = 1.91, 95% confidence interval = 1.53–2.38, P < 0.001). The addition of change in total LAEF to an AF risk score improved model discrimination and reclassification (net reclassification improvement = 0.107, P = 0.017; integrative discrimination index = 0.049, P < 0.001). Conclusion In this multi-ethnic study population free of clinical cardiovascular disease at baseline, a greater increase in LA volumes and decrease in LA function were associated with incident AF. The addition of change in total LAEF to risk prediction models for AF improved model discrimination and reclassification of AF risk.

Altered left atrial 4D flow characteristics in patients with paroxysmal atrial fibrillation in the absence of apparent remodeling

“…Although main LA volume parameters were higher and total LA function was lower in absolute numbers in patients with paroxysmal AF than controls, the differences were not statistically significant. These results do not entirely comply with the accumulated clinical evidence, which reveal that AF leads to enlargement and dysfunction of the left atrium over time 9 – 11 . The most likely explanation may be that the sample size of the study was not large enough to provide significant differences or patients with large LA volumes were not included in the study, since the patients were in the workup for pulmonary vein isolation.…”

“…Since AF is believed to be a progressive disease leading to atrial dilation and mechanical dysfunction of the left atrium over time 8 , 9 , structural and functional remodeling may also play a role in the occurrence of thromboembolic events in AF patients 10 , 11 . The interplay between LA remodeling and flow patterns, however, is poorly characterized.…”

Characterization of cardiac mechanics and incident atrial fibrillation in participants of the Cardiovascular Health Study

“…Recently, LA reservoir strain has been associated with incident AF in small cohorts over a relatively short duration of follow-up (8,15). Additionally, LA strain as measured by cardiac magnetic resonance has also been associated with incident AF (16,17). Our primary study findings extend the body of evidence supporting the temporal association of subclinical alterations in LA mechanics with incident AF to a large, community-based elderly cohort with high rates of AF over the course of 10 years.…”

Association of arterial stiffness with incident atrial fibrillation: a cohort study

“…Despite the evidence for a potential bidirectional relationship between arterial stiffening and hypertension, stiff arteries can be part of the substrate for high systemic blood pressure leading to adverse left ventricular remodeling [ 24 ]. Adverse left ventricular changes, including concentric hypertrophy and altered geometry, are known to be associated with structural and functional changes in the left atrium that ultimately increase AF risk [ 25 ]. In fact, animal models have shown that atrial fibroblasts have greater fibrotic potential than their ventricular counterparts, suggesting that the left atrium is more sensitive to adverse vascular remodeling than the left ventricle [ 26 ].…”