Determinants of Left Atrial Volume in Patients with Atrial Fibrillation

PLoS One. 2016 Oct 4;11(10):e0164145. doi: 10.1371/journal.pone.0164145. eCollection 2016.

Abstract

Introduction: Left atrial (LA) enlargement is an important risk factor for incident stroke and a key determinant for the success of rhythm control strategies in patients with atrial fibrillation (AF). However, factors associated with LA volume in AF patients remain poorly understood.

Methods: Patients with paroxysmal or persistent AF were enrolled in this study. Real time 3-D echocardiography was performed in all participants and analyzed offline in a standardized manner. We performed stepwise backward linear regression analyses using a broad set of clinical parameters to determine independent correlates for 3-D LA volume.

Results: We included 210 patients (70.9% male, mean age 61±11years). Paroxysmal and persistent AF were present in 95 (45%) and 115 (55%) patients, respectively. Overall, 115 (55%) had hypertension, 11 (5%) had diabetes, and 18 (9%) had ischemic heart disease. Mean indexed LA volume was 36±12ml/m2. In multivariable models, significant associations were found for female sex (β coefficient -10.51 (95% confidence interval (CI) -17.85;-3.16), p = 0.0053), undergoing cardioversion (β 11.95 (CI 5.15; 18.74), p = 0.0006), diabetes (β 14.23 (CI 2.36; 26.10), p = 0.019), body surface area (BSA) (β 34.21 (CI 19.30; 49.12), p<0.0001), glomerular filtration rate (β -0.21 (CI -0.36; -0.06), p = 0.0064) and plasma levels of NT-pro brain natriuretic peptide (NT-proBNP) (β 6.79 (CI 4.05; 9.52), p<0.0001), but not age (p = 0.59) or hypertension (p = 0.42). Our final model explained 52% of the LA volume variability.

Conclusions: In patients with AF, the most important correlates with LA volume are sex, BSA, diabetes, renal function and NT-proBNP, but not age or hypertension. These results may help to refine rhythm control strategies in AF patients.

MeSH terms

  • Aged
  • Atrial Fibrillation / blood
  • Atrial Fibrillation / diagnostic imaging*
  • Atrial Fibrillation / physiopathology
  • Atrial Function, Left
  • Cardiac Volume
  • Echocardiography, Three-Dimensional / methods*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Natriuretic Peptide, Brain / blood*
  • Peptide Fragments / blood*

Substances

  • Peptide Fragments
  • pro-brain natriuretic peptide (1-76)
  • Natriuretic Peptide, Brain

Grant support

The study was supported by a grant of the Mach Gaensslen Foundation and the University Hospital Basel. Matthias Bossard was supported by a grant of the University of Basel and the Freie Akademische Gesellschaft (FAG) Basel. David Conen and Beat Kaufmann were supported by grants of the Swiss National Science Foundation (PP00P3_133681 and PP00P3_159322 to David Conen, 3232B0_141603 and 310030_149718 to Beat Kaufmann).