Risk stratification of patients with atrial fibrillation: Biomarkers and other future perspectives

Table 4 Echocardiographic parameters associated with thromboembolism in atrial fibrillation

Transthoracic echocardiogram	Left ventricle systolic dysfunction has long been known to be associated with thromboembolism in atrial fibrillation and is currently used in the CHA2DS2-VASc score[4]
	Left atrial diameter was shown to be associated with thromboembolism in old studies. Nowadays, diameter is not considered an appropriate way of assessing left atrial size[21]
	Left atrial area and volume have been shown to be associated with the presence of left atrial appendage thrombus and other markers of left atrial stasis[22]. Studies concerning hard clinical endpoints are still lacking[23]
	Left atrial deformation assessment (strain and strain rate) holds promise in this field, since it translates changes in atrial kinetics and function
Transesophageal echocardiogram	Left atrial appendage thrombus, spontaneous echocardiographic contrast and low flow velocities in the left atrial appendage have been associated with a high risk of thromboembolic events and an adverse prognosis[22]
	The invasive nature of this technique makes it inadequate for wide usage in AF patients