Predictive value of lipoprotein(a) for left atrial thrombus or spontaneous echo contrast in non-valvular atrial fibrillation patients with low CHADS-VASc scores: a cross-sectional study.

Objective: Current guidelines are debated when it comes to starting anticoagulant therapy in patients with non-valvular atrial fibrillation (NVAF) and low CHADS-VASc scores (1-2 in women and 0-1 in men). However, these individuals still have a high likelihood of developing left atrial thrombus/spontaneous echo contrast (LAT/SEC) and experiencing subsequent thromboembolism. Recent research has demonstrated that lipoprotein(a) [Lp(a)] may increase the risk of thrombosis, but the relationship between Lp(a) and LAT/SEC in NVAF patients is not clearly established. Therefore, this study sought to evaluate the predictive ability of Lp(a) for LAT/SEC among NVAF patients with low CHADS-VASc scores.

Methods: NVAF patients with available transesophageal echocardiography (TEE) data were evaluated. Based on the TEE results, the subjects were classified into non-LAT/SEC and LAT/SEC groups. The risk factors for LAT/SEC were examined using binary logistic regression analyses and were validated by using 1:1 propensity score matching (PSM). Subsequently, novel predictive models for LAT/SEC were developed by integrating the CHADS-VASc score with the identified factors, and the accuracy of these models was tested using receiver operating characteristic (ROC) analysis.

Results: In total, 481 NVAF patients were enrolled. The LAT/SEC group displayed higher Lp(a) concentrations. It was found that enlarged left atrial diameter (LAD), high concentrations of Lp(a), and a history of coronary heart disease (CHD) were independent predictors of LAT/SEC. Lp(a) and LAD still had predictive values for LAT/SEC after adjusting for PSM. In both the highest quartile groups of Lp(a) (>266 mg/L) and LAD (>39.5 mm), the occurrence of LAT/SEC was higher than that in the corresponding lowest quartile. By incorporating Lp(a) and the LAD, the predictive value of the CHADS-VASc score for LAT/SEC was significantly improved.

Conclusion: Elevated Lp(a) and enlarged LAD were independent risk factors for LAT/SEC among NVAF patients with low CHADS-VASc scores. The prediction accuracy of the CHADS-VASc score for LAT/SEC was significantly improved by the addition of Lp(a) and LAD. When evaluating the stroke risk in patients with NVAF, Lp(a) and LAD should be taken into account together with the CHADS-VASc score.

Trial Registration: Retrospectively registered.