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

Abstract

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<0.0001), a sensitivity of 0.872, and a specificity of 0.978. Sequential analysis revealed that LA contraction circumferential strain had a high diagnostic efficacy for stroke, as well as a specified accuracy in the diagnosis of hypertension and diabetes in patients aged ≥65 years old. However, it was not found to be effective in the diagnosis of heart failure and vascular diseases.Conclusions: LAS is a useful index for the dynamic evaluation of LA function in patients with nonvalvular AF, with higher sensitivity and accuracy than LA volume. LA contraction circumferential strain is an independent high risk factor for thromboembolism, and LA contraction circumferential strain >-4.5% is a valuable cut-off to guide the use of anticoagulant therapy in patients with non-valvular AF.

Could premature ventricular contractions lead to atrial remodeling?

“…The strain duration for each frame was then determined using the formula s ( t ) = ( L ( t ) L (tr))/ L (tr) × 100%, where L ( t ) is the line length at time t and tr is the end‐diastolic time of the left ventricle. To determine the global strain, the strains of all significant directional lines were averaged 9,17,18 …”

“…A dataset was eliminated if the LA endocardial boundary was missing or ambiguous. To enhance the precision and repeatability of the measurements, high‐resolution pictures were acquired 9,15,16 …”

“…In the last two steps of the length decrease of the LA wall, the strains had negative values. This method generated LA longitudinal strain parameters, including LA conduit strain (LAScd), LA reservoir strain (LASr), and LA contraction strain (LASct), as well as LA circumferential strain parameters, including LA conduit circumferential strain (LAScdc), LA reservoir circumferential strain (LASr-c), and LA contraction circumferential strain (LASct-c) 9,17,18 (Figure 1).…”

“…Despite its effectiveness, the therapeutic value of STE is limited by its thin‐walled design, irregular organization of myocytes in the LA, and intervenor variability. The four‐dimensional automated left atrial quantification (4D Auto LAQ) tool is an analytical method that use three‐dimensional volume data to quantify the left atrial (LA) volume and left atrial longitudinal and circumferential strains 7–9 …”

“…tool is an analytical method that use three-dimensional volume data to quantify the left atrial (LA) volume and left atrial longitudinal and circumferential strains. [7][8][9] This study aims to examine the relationship between PVC and abnormal LA function as measured by LA strain evaluation using a 4D Auto LAQ.…”