Right Atrial Thrombosis and Pulmonary Embolism: A Narrative Review

Predictive indicators in peripheral blood and left atrium blood for left atrial spontaneous echo contrast in atrial fibrillation patients

OBJECTIVES

The purpose of this study was to demonstrate the discriminating predictive indicators in peripheral blood and left atrium blood for predicting the risk of left atrial spontaneous echo contrast (LASEC) in atrial fibrillation patients underwent catheter ablation.

METHODS

A total of 108 consecutive AF patients treated with radiofrequency ablation between July 2022 and July 2023 were enrolled and divided into two groups based on preprocedural transesophageal echocardiography: the non LASEC group (n = 71) and the LASEC group (n = 37). Circulating platelet and endothelial- derived MPs (PMPs and EMPs) in peripheral blood and left atrial blood were detected. Plasma soluble P-selectin (sP-selectin) and von Willebrand factor (vWF) were observed. Diagnostic efficiency was measured using receiver operating characteristic (ROC) curve.

RESULTS

Peripheral sP-selectin, vWF and EMPs expressions elevated in all subjects when compared to those in left atrium blood. Levels of sP-selectin and vWF were significantly higher in peripheral blood of LASEC group than those of non LASEC group (p = 0.0018,p = 0.0271). Significant accumulations of peripheral PMPs and EMPs were documented in LASEC group by comparison with non LASEC group (p = 0.0395,p = 0.018). The area under curve(AUC) of combined PMPs and sP-selectin in predicting LASEC was 0.769 (95%CI: 0.678-0.845, sensitivity: 86.49%, specificity: 59.15%), significantly larger than PMPs or sP-selectin alone.

CONCLUSIONS

Expressions of PMPs, sP-selectin, EMPs and vWF Increased in NVAF patients with LASEC and that might be potential biomarkers for LASEC prediction.

Causal effect of atrial fibrillation on pulmonary embolism: a mendelian randomization study

Atrial fibrillation (AF) can increase thrombosis, especially arterial thrombosis, and some studies show that AF patients have a higher risk of developing pulmonary embolism (PE). The objective of our study is to investigate whether there is a direct causal effect of AF on PE. A two-sample Mendelian randomization (MR) approach was utilized to determine whether there is a causal relationship between AF and PE. European population-based consortia provided statistical data on the associations between Single Nucleotide Polymorphisms (SNPs) and relevant traits. The AF dataset was obtained from genome-wide association studies (GWAS) comprising 60,620 cases and 970,216 controls, while a GWAS of 1846 cases and 461,164 controls identified genetic variations associated with PE. Estimation of the causal effect was mainly performed using the random effects inverse-variance weighted method (IVW). Additionally, other tests such as MR-Egger intercept, MR-PRESSO, Cochran's Q test, "Leave-one-out," and funnel plots were conducted to assess the extent of pleiotropy and heterogeneity. Using 70 SNPs, there was no evidence to suggest an association between genetically predicted AF and risk of PE with multiplicative random-effects IVW MR analysis (odds ratio = 1.0003, 95% confidence interval: 0.9998-1.0008, P = 0.20). A null association was also observed in other methods. MR-Egger regression and MR-PRESSO respectively showed no evidence of directional (intercept, - 2.25; P = 0.94) and horizontal(P-value in the global heterogeneity test = 0.99) pleiotropic effect across the genetic variants. No substantial evidence was found to support the causal role of AF in the development of PE.

Case report: A rare case of recurrent right atrial mass dramatically disappeared after anticoagulation

A young man repeatedly found a right atrial mass with severe wheezing and extreme dyspnea. His condition was critical and complicated. The process of correct diagnosis was full of twists and turns. Finally, he got better and was discharged from the hospital after anticoagulation therapy, which suggested that correct clinical thinking and decision are particularly important in the process of diagnosis and treatment.

Atrial thrombosis: Not only left, think also about right!

Atrial fibrillation (AF) is the most common arrhythmia in the general population. Systemic thromboembolism from left atrial appendage (LAA) thrombosis is a well-known complication of AF, whereas thromboembolic complications from a right atrial (RA) thrombus are infrequent. Nevertheless, the prevalence of RA thrombosis is debated; despite having a low prevalence in echocardiographic studies, the higher prevalence found in autoptic studies rises the hypothesis of an under detection of RA clots, possibly related to the limited evaluation of right atrial appendage (RAA) with non-invasive imaging. Here we present a review of the current literature about RA thrombosis, regarding its diagnosis, differentials, and best treatment options.