Evaluation of left ventricular systolic function during atrial fibrillation: Is it reliable?

For adequate treatment of patients with atrial fibrillation (AF) clinicians need information on left ventricular (LV) systolic function. This is generally evaluated using echocardiography to calculate LV ejection fraction (LV-EF) or global longitudinal strain (GLS), which can detect early systolic abnormalities when LV-EF is still normal. In using both LV-EF and GLS the key point is that measures should be reliable and reproducible, regardless of cardiac rhythm. Unfortunately, many clinicians question the reliability of the echocardiographic measures during AF because of several reasons. First, AF patients are often excluded in echocardiographic studies, thus data for the validity of systolic function indices during AF are limited [ 1 ]. Second, the prognostic value of cardiac function parameters may be affected by AF [ 2 ]. Third, methods to improve assessment of LV function during AF are rarely applied in echocardiographic practice because they are generally cumbersome and time-consuming, and many echocardiographers just rely on eye-ball evaluations. Thus, assessment of cardiac function in patients with AF is problematic.