Echocardiographic Risk Assessment to Guide Screening for Atrial Fibrillation

Abstract

Although atrial fibrillation (AF) is a significant population health burden, and an avoidable cause of stroke, AF screening remains controversial. The aim of this study was to investigate whether coincidental echocardiography could provide information about patients at risk for AF. Asymptomatic participants ≥65years of age with more than one AF risk factor (N=445) undergoing echocardiography for risk evaluation were followed over a median of 15months for incident AF. Left atrial volume index (LAVi), left ventricular (LV) global longitudinal strain (GLS; absolute value), left atrial (LA) strain, and LV mass were measured. During the follow-up period, AF was diagnosed clinically by primary care physicians or by using a single-lead portable electrocardiographic monitoring device (five 60-sec recordings performed by participants over 1week). AF was diagnosed in 45 patients (10%; mean age, 70.5±4.2years; 55% women). AF detection was higher in those with LV hypertrophy, GLS < 16%, LAVi > 34mL/m2, and LA reservoir strain < 34%. GLS, LAVi, and LA reservoir strain were independently associated with AF (P<.05). Those with AF had reduced GLS, higher LAVi, and higher LV mass (P<.05), but LA strain was similar in both groups (P>.05). GLS and LAVi were the strongest predictors, and cut points of 14.3% for GLS and 39mL/m2 were associated with increased risk for developing AF. Those with all four risk parameters (LV hypertrophy, GLS<16%, LA reservoir strain <34%, and LAVi>34mL/m2) had a 60% AF detection rate, compared with 7% without these features (P=.004). Echocardiography is widely used in patients at risk for AF, and simple LV and LA measurements may be used to enrich the process of AF screening.