The Copenhagen City Heart Study set out to investigate whether left atrial (LA) functional measures predict atrial fibrillation (AF) in the general population. They found that LA functional measures predict AF in the general population and can provide prognostic information. The results were published in JACC: Cardiovascular Imaging.
They also found that in individuals without hypertension and nondilated LA, these measures indicated an increased risk of AF.
The community based cohort study looked at approximately 2,000 individuals who had undergone a transthoracic echocardiogram. Conventional echocardiographic measures and extended LA measures, including the minimal and maximal LA volumes (LAVmin and LAVmax, respectively) and left atrial emptying fraction (LAEF), were performed. The endpoint was incident AF, and participants with known AF were excluded, which left 1,951 for inclusion.
Over 11 years of follow-up, 184 (9.4%) developed AF. Those who developed AF had significantly larger LA volumes and lower LAEF than participants without AF. These LA measures were univariable predictors of AF. All LA measures remained predictors independent of clinical risk scores, with LAVmin providing the highest C-statistics when added to these risk scores. However, hypertension modified the relationship between the measures of LA function (both LAVmin and LAEF) and risk of AF, which was not the case for LAVmax. The measures of LA function mainly provided prognostic information regarding risk of AF in participants without hypertension. Even when analysis was restricted to individuals without hypertension and nondilated LA, the LAVmin and LAEF remained significantly independent predictors of AF after multivariable adjustments.