Left atrial (LA) size is a marker of diastolic dysfonction and is associated with cardio-vascular outcomes. A new method using a non contrast-enhanced cardiac computed tomography realised for the quantification of coronary artery calcium (CAC) allows to mesure left atrial volume. The aim of this study was to determine the cardio-vascular risks factors associated with left atrial enlargement.
Design and method:
458 participants (mean age 59,4 years, 45,4%of women) at intermediate cardio-vascular risk benefited from a non contrast-enhaced cardiac computed tomography. Left atrial volume was performed by countouring the inner edges of LA in three shots of space.
Mean LA volume was 76,7 ± 18,6 mL and 41,6 ± 10 mL/m2 after adjustement with body area. Women had significatively largest LA volume (p < 0,0001). LA volume was strongly associated with body mass index and body area (bêta coefficient = 0,27 et p < 0,0001 for both). Obesity (BMI > 30 kg/m2) was correleted with largest LA volume (p < 0,0001). Systolic blood pressure was associated with LA volume and adjusted LA volume (p respectively < 0,01 et 0,01) but the association with hypertension was only found with non adjusted LA volume (p = 0,003). Dyslipidemia was correleted with smaller LA (p < 0,01). Smoking, diabetes and CAC was not associated with LA size. In a fully adjusted model, hypertension, female sex and dyslipidemia was still associated with adjusted LA volume.
LA volume determined using non contrast-enhanced computed tomography is associated with BMI, hypertension, female sex and dyslipidemia. This new technique allows to mesure left atrial volume on a cardiac computed tomography used for the assessment of CAC to better predict the cardiovascular risk.