Left atrial strain measured by 4D Auto LAQ echocardiography is significantly correlated with high risk of thromboembolism in patients with non-valvular atrial fibrillation.

Background The 4-dimensional automated left atrial quantification (4D Auto LAQ) tool is a new software for analysis of the structure and function of the left atrium (LA). This study aimed to evaluate the relationship between LA strain (LAS) as measured by 4D Auto LAQ echocardiography and thromboembolism risk in patients with non-valvular atrial fibrillation (NVAF). Methods Eight-five patients with NVAF were recruited from the cardiovascular center of our hospital, including 39 patients at high risk and 46 patients at low risk of thromboembolism. The study participants were assessed by routine echocardiography; 4D images were obtained, after which 4D Auto LAQ assessment was performed. Results In the thromboembolism high-risk group, the rates of impaired LA reservoir strain, LA contraction strain, LA reservoir circumferential strain, LA conduit circumferential strain, and LA contraction circumferential strain were found to be significantly higher than in the low-risk group. However, there was no significant difference in volume at onset of LA contraction or LA ejection fraction (LAEF) between the 2 groups. LA contraction circumferential strain was found to be an independent high risk factor for thromboembolism [odds ratio (OR): 2.52; P=0.008]. LA contraction circumferential strain >-4.5% was the cut-off for differentiating between participants with high and low risk of thromboembolism, with an area under the curve (AUC) of 0.95 (P -4.5% is a valuable cut-off to guide the use of anticoagulant therapy in patients with non-valvular AF.