Morphological changes in the orifices of the left atrial appendage and left atrium in patients with atrial fibrillation

Abstract

Background: As an integral part of the left atrium (LA), the left atrial appendage (LAA) plays an important role in atrial fibrillation (AF). However, the relationship between LAA remodeling and AF has not been clearly defined. This retrospective case-control study aimed to assess the morphological and functional features of the LA and the LAA in AF patients using images obtained by computed tomography angiography (CTA).Methods: A total of 140 AF patients and 64 patients without AF or other cardiovascular diseases who underwent CTA scans between September 2016 and August 2017 were enrolled in this observational study as the experimental and the control groups, respectively. The major and minor axes, area, and perimeter of the LAA orifice, the LAA depth, and the volume of both the LAA and LA were analyzed. The data of the AF group and the control group were compared. The t-test was used to analyze the normally distributed data, and the Wilcoxon rank-sum test was used for abnormally distributed data. The best critical value of predictors of AF was calculated using receiver operating characteristic (ROC) curve analysis. The correlation of the LAA volume change with the major and minor axes, area, and perimeter of the LAA orifice, and the LAA depth were analyzed using the Pearson correlation coefficient. Results:The LAA orifice's minor axis, LAA volume, and LA volume were significantly greater (P=0.004, P=0.010, and P<0.001, respectively) in patients with AF than in those without AF. The LAA volume [95% confidence interval (CI): 1.01 to 1.30; P=0.038] and LA volume (95% CI: 1.03 to 1.07; P<0.001) were significantly independent predictors of AF. An LAA volume of 8.75 mL had the highest predictive value for AF [area under the curve (AUC), 0.612], with a sensitivity of 76.6% and a specificity of 48.6%. In contrast, an LA volume of 97.15 mL had the highest predictive value for AF (AUC, 0.771), with a sensitivity of 90.6% and a specificity of 53.6%. The change of LAA volume was positively weakly correlated with the area and perimeter of the LAA orifice (r=0.1703 and r=0.1378, respectively). The LAA emptying fraction was negatively correlated with the major axis and the area of the LAA orifice. The major and minor axes, area, and perimeter of the LAA orifice, and LAA depth were significantly greater in female than in male patients (P=0.003, P=0.003, P=0.001, P=0.019, and P<0.001, respectively). Conclusions:The AF patients had a longer minor axis of the LAA orifice than that of the control group, resulting in a more circular LAA orifice. The LAA orifice area and perimeter were positively correlated with LAA volume change. The LAA orifice major and minor axes, area, and perimeter, and the LAA depth of the female patients were significantly greater than those of their male counterparts in AF patients.

Dense SEC connection with Left Atrial Appendage Asynchrony and Mechanical Function in patients with Non-Valvular Atrial Fibrillation

“…It because prolonged AF will cause delayed contraction of left atrial appendage neck. The studies showed [24]the morphologic change of the LAA ori ce in AF patients was more circular than that of the control participants, Therefore, there is little difference in dispersion of peak time in the basal segment of left atrial appendage, which is consistent with our research results. The LAA ori ce major and minor axes, area, and perimeter, and the LAA depth of the female patients were signi cantly greater than those of their male [24].…”

“…The studies showed [24]the morphologic change of the LAA ori ce in AF patients was more circular than that of the control participants, Therefore, there is little difference in dispersion of peak time in the basal segment of left atrial appendage, which is consistent with our research results. The LAA ori ce major and minor axes, area, and perimeter, and the LAA depth of the female patients were signi cantly greater than those of their male [24]. However, basal segments of the LAA such as left lateral ridge (LLR) and baso-medial appendage segment (BMAS) near the vestibule of the mitral valve are composed of over 4 mm thick myocardial tissue [25,26].…”

Cardiac computed tomography angiography-derived pulmonary vein volumetry as a predictor for atrial fibrillation recurrence after catheter ablation

“…The left atrial volume, measured by CT or magnetic resonance imaging (MRI), is a widely used parameter in studies on AF and is a superior measurement in terms of its accuracy and reproducibility, and prognostic power ( 5 , 14 - 16 ). The current study is consistent with prior research ( 5 , 14 , 15 ).…”

Association of quantitative computed tomography-based right atrial appendage and right atrium parameters with postradiofrequency ablation recurrence of atrial fibrillation

“…Ectopic pacemakers in patients with AF mainly originate in the pulmonary vein, and pulmonary vein isolation is the cornerstone of catheter ablation ( 19 ). Therefore, the risk predictors of postradiofrequency ablation AF recurrence in previous studies were mostly concentrated in the LA, LAA, and pulmonary vein ( 20 , 21 ). Santangeli et al noted that the incidence of extrapulmonary venous triggered lesions in patients with AF was 11%, and the common sites were the crista terminalis, SVC, RAA, and LAA ( 22 ).…”