3224Incremental benefit of left ventricular global longitudinal strain over clinical and left atrial parameters for predicting new-onset atrial fibrillation

Abstract

Abstract Background Although LV hypertrophy and dysfunction are associated with atrial fibrillation (AF), AF often occurs in the absence of LV hypertrophy or reduced ejection fraction. The effect of subclinical LV dysfunction on AF has not been fully studied. Purpose We sought the association between subclinical LV dysfunction (measured with global longitudinal strain, GLS) and new-onset AF. Methods This observational study evaluated 531 consecutive patients (median age, 67 years [interquartile range, 56 to 78]; 56% male), without a history of AF who underwent strain echocardiography after cryptogenic stroke. The CHARGE-AF score was used to calculate the 5-year risk of developing AF. Standard echocardiographic parameters were measured, and speckle-tracking was used to measure LA (reservoir strain, pump strain, and conduit strain) and LV strain (GLS). A strain analysis was conducted using a dedicated software package, using R-R gating. The baseline clinical and echocardiographic parameters of the patients who developed AF and those who did not were compared. Results Over 2.5 years of follow-up, 61 patients (11%) had new-onset AF. Patients who developed AF were older, had a higher CHARGE-AF score, larger LA volume, worse LA strain, and worse GLS than those who did not. Areas under the receiver-operating curve for GLS (0.84) was comparable to CHARGE-AF (0.79), LA pump strain (0.83), and LA reservoir strain (0.85). In the nested Cox models, GLS demonstrated an independent and incremental predictive value over the clinical and LA parameters (Figure). Moreover, adding GLS to the combined clinical and LA parameters model resulted in a significantly improved reclassification (net reclassification improvement, 0.32; p=0.016). Importantly, the predictive value of GLS was confirmed in patients with abnormal LA volumes (LA volume index≥34ml/m2) but not in patients with normal LA volumes. Figure 1 Conclusion GLS is associated with new-onset AF, especially in patients with abnormal LA volumes. This effect is independent of and incremental to the clinical and LA parameters.