Regular Alcohol Consumption Is Associated With Impaired Atrial Mechanical Function in the Atrial Fibrillation Population: A Cross-Sectional MRI-Based Study

Abstract

Objectives: This study sought to determine the impact of regular alcohol consumption on left atrial (LA) mechanical and reservoir function.

Background: Earlier studies suggest that regular alcohol intake is associated with increased atrial fibrillation (AF) and LA dilatation.

Methods: This study prospectively enrolled 160 patients with paroxysmal or persistent AF to undergo 3-T cardiac magnetic resonance (CMR) imaging in sinus rhythm. Patients self-reported alcohol consumption in standard drinks (∼12 g alcohol) per week over the preceding 12 months and were categorized into 4 groups: 1) lifelong nondrinkers; 2) mild drinkers (3 to 10 standard drinks/week); 3) moderate drinkers (11 to 20 standard drinks/week); 4) heavy drinkers (>20 standard drinks/week). Permanent AF and cardiomyopathy were excluded. On CMR, maximum LA volume (LA_max) and minimum LA volume (LA_min), global LA emptying fraction (LAEF) as (LA_max - LA_min) / LA_max, and LA reservoir function as (LA_max - LA_min) / LA_min were calculated.

Results: Regular alcohol consumption (mean 15.8 ± 6.9 standard drinks/week, n = 120) was associated with larger LA size (LA volume index 50 ± 13 ml/m² vs. 43 ± 12 ml/m²; p = 0.005), reduction in LAEF (40 ± 14% vs. 52 ± 15%; p < 0.001), and reduction in reservoir function (77 ± 48% vs. 119 ± 63%; p < 0.001) compared with lifelong nondrinkers (n = 40). There were progressive dose-related impairments in LAEF (mild 45.4 ± 13.5% vs. moderate 39.1 ± 14.7% vs. heavy drinkers 35.6 ± 12.6%; p < 0.01) and reservoir function (mild 95.8 ± 55.6% vs. moderate 74.8 ± 47.1% vs. heavy drinkers 61.7 ± 34.4%; p < 0.01). Predictors of atrial mechanical dysfunction included weekly alcohol intake (p = 0.001), older age (p = 0.018), and persistent AF (p = 0.016), but not binge drinking or beverage type.

Conclusions: In patients with AF, habitual alcohol consumption is associated with significantly increased LA size and atrial mechanical dysfunction compared with nondrinkers.

Keywords: alcohol; atrial fibrillation; atrial myopathy; cardiac magnetic resonance; left atrium.