Predictive effect of hyperuricemia on left atrial stasis in non-valvular atrial fibrillation patients

Omitting transesophageal echocardiography before catheter ablation of atrial fibrillation

BACKGROUND

Data about necessity of performing transesophageal echocardiography (TOE) prior to every catheter ablation (CA) of atrial fibrillation (AF) is scarce. We aimed to evaluate the safety of an individualized risk-based approach to TOE with respect to thromboembolic cerebrovascular events (CVE) in patients undergoing CA for AF or left atrial tachycardia (AT).

METHODS

We performed a retrospective clinical study based on our institutional registry database. Patients undergoing CA for AF or left-sided AT following initial AF ablation at two participating centers were enrolled. Prior to the procedure, patients were scheduled for TOE only if they had a history of thromboembolic stroke, left atrial appendage (LAA) thrombus, or inappropriate anticoagulation regimen in the previous 3 to 4 weeks. The incidence of periprocedural cerebrovascular thromboembolic events was assessed.

RESULTS

We analyzed 1155 patients (median age 70 years, 54.8% male, 48.1% had persistent AF/AT). In 261 patients, a TOE was performed; in 2 patients (0.7%), an LAA thrombus was detected, which led to cancellation of the catheter ablation; in 894 patients, the TOE was omitted. Of the 1153 (0.35%) patients who underwent ablation, 4 (0.35%) experienced a CVE (one TIA and three strokes). The rate of CVE in our study does not exceed that reported in most multicenter trials. The low event rates limited statistical analysis of possible risk factors for CVE. In all 4 patients with CVE, post-CVE imaging showed the absence of LAA thrombus.

CONCLUSIONS

An individualized selective approach to TOE before catheter ablation of AF or left AT showed a very low risk of overt intraprocedural thromboembolic events for the population in our study. A further randomized controlled study is needed to determine whether TOE prior to catheter ablation without ICE could be omitted in patients with uninterrupted OAC without previous thromboembolic events or a history of left atrial thrombus.

A nomogram to predict ventricular thrombus in dilated cardiomyopathy patients

BACKGROUND

VT (Ventricular Thrombus) is a serious complication of dilated cardiomyopathy (DCM). Our goal is to develop a nomogram for personalized prediction of incident VT in DCM patients.

METHODS

1267 patients (52.87 ± 11.75 years old, 73.8% male) were analyzed retrospectively from January 01, 2015, to December 31, 2020. A nomogram model for VT risk assessment was established using minimum absolute contraction and selection operator (LASSO) and multivariate logistic regression analysis, and its effectiveness was validated by internal guidance. The model was evaluated by the area under the receiver operating characteristic curve (AUC), calibration curves, and decision curve analysis (DCA). We compared the performance in predicting VT between nomogram and CHA2DS2, CHA2DS2- VASc or ATRIA by AUC, akaike information criterion (AIC), bayesian information criterion (BIC), net reclassification index (NRI), and integrated discrimination index (IDI).

RESULTS

89 patients (7.02%) experienced VT. Multivariate logistic regression analysis revealed that age, left ventricular ejection fraction (LVEF), uric acid (UA), N-terminal precursor B-type diuretic peptide (NT-proBNP), and D-dimer (DD) were important independent predictors of VT. The nomogram model correctly separates patients with and without VT, with an optimistic C score of 0.92 (95%CI: 0.90-0.94) and good calibration (Hosmer-Lemeshow χ2 = 11.51, P = 0.12). Our model showed improved prediction of VT compared to CHA2DS2, CHA2DS2-VASc or ATRIA (all P < 0.05).

CONCLUSIONS

The novel nomogram demonstrated better than presenting scores and showed an improvement in predicting VT in DCM patients.

Uric acid significantly correlates with the presence of low-voltage areas at the endocardial mapping in patients with non-valvular atrial fibrillation

BACKGROUND AND AIMS

Interest in the role of atrial substrate in maintaining Atrial Fibrillation (AF) is growing. Fibrosis is the culprit in the electrical derangement of the myocytes. Many cardiovascular risk factors are known to be linked to atrial scarring; among them Uric Acid (UA) is emerging. The purpose of our study is to find whether UA is associated with Left Atrium (LA) with pathological substrate.

METHODS AND RESULTS

81 patients who underwent radiofrequency transcatheter ablation for nonvalvular AF at the cardiological department of the Niguarda Hospital were enrolled in an observational, cross-sectional, single-center study. UA levels were analysed before the procedure. High density electroanatomic mapping of the LA was performed and patients were divided according to the presence or not of areas of pathological substrate (bipolar voltage <0.5 mV in sinus rhythm). 19 patients showed a LA with pathological substrate. These subjects showed a significant higher prevalence of persistent phenotype of AF (84.2 vs. 25.8%, p < 0.001). UA levels were significantly higher in the group of patients with LA with pathological substrate (6.8 ± 1.9 vs 5.3 ± 1.4 mg/dL, p < 0.001) as well as the prevalence of hyperuricemia (26.5 vs. 6.5%, p = 0.021). The association between uric acid LA with pathological substrate remains significant even after correction for confounding factors (age, left ventricular dysfunction, valvular disease, arrythmia phenotype and furosemide use) and also when the ratio UA/creatinine was evaluated.

CONCLUSIONS

In a population of patients who underwent AF ablation, higher UA levels were significantly associated with pathological LA substrate at electro-anatomical mapping.

Construction of a Clinical Predictive Model of Left Atrial and Left Atrial Appendage Thrombi in Patients with Nonvalvular Atrial Fibrillation

Background. The purpose of this study was to investigate the risk factors of left atrial (LA) or left atrial appendage (LAA) thrombi in patients with nonvalvular atrial fibrillation (NVAF) and to establish and validate relevant predictive models. It might improve thromboembolic risk stratification in patients with NVAF. Methods. This study retrospectively included 1210 consecutive patients with NVAF undergoing transesophageal echocardiography (TEE), of whom 139 patients had thrombi in LA or in LAA. Through literature review and the ten events per variable (10EPV) principle, 13 variables were finally identified for inclusion in multivariate analysis. Models were constructed by multivariate logistic stepwise regression and least absolute shrinkage and selection operator (lasso) regression. Results. After logistic regression, five variables (AF type, age, B-type natriuretic peptide, E/e’ ratio, and left atrial diameter) were finally screened out as model 1. After Lasso regression, AF type, age, gender, B-type natriuretic peptide, E/e’ ratio, left atrial diameter, and left ventricular ejection fraction were finally screened as model 2. After comparing the two models, the simpler model 1 was finally selected. The area under the ROC curve (AUC) of the model 1 was 0.865 (95% CI: 0.838–0.892), the Hosmer–Lemeshow test = 0.898, and the AUC = 0.861 after internal validation. The clinical decision curve showed that the new clinical prediction model could achieve a net clinical benefit when the expected threshold was between 0 and 0.6. Conclusion. This study constructed a new clinical prediction model of LA or LAA thrombi, with a higher discriminative degree than the CHADS2 and CHA2DS2-VASc scoring systems (AUC: 0.865 vs. 0.643; AUC: 0.865 vs 0.652).

The Relationship between Uric Acid and the Development, Complication, and Prognosis of Atrial Fibrillation: The Views from a Clinical Study

A large number of studies suggest that uric acid (UA) is related to the occurrence, complications, and prognosis of atrial fibrillation (AF). However, the guidelines did not clearly elaborate on this issue. The current research results need to be summarized to analyze the association between UA and AF. This study found that in the current clinical research on the relationship between UA and AF, studies mainly focus on the development or complications of AF. A lot of repetitive work does not deepen awareness of this question. In contrast, studies investigating the effects of UA-lowering therapy on the management of AF are limited. The only reports deny the protective effect of UA-lowering therapy. For now, we suggest that UA is close to the occurrence and progression of AF; therefore, it may have important significance as a clinical marker. The role of UA-lowering therapy in the management of AF is one of the next key issues to be explored. It will be a meaningful topic to focus on the latest research on AF ablation and to conduct a secondary analysis to explore the prognostic impact of UA on the latest treatment methods for AF. Multiomics techniques may allow us to have a deeper understanding of the role of UA in AF management in the future.

The long-term efficacy and safety of combining ablation and left atrial appendage closure: A systematic review and meta-analysis

BACKGROUND

Combined ablation and left atrial appendage closure (LAAC) is an alternative for atrial fibrillation patients with a high risk of stroke. However, the long-term outcomes of this combined procedure remain elusive.

METHODS

PubMed, Embase, Cochrane Library, and Web of Science were systematically searched from the establishment of databases to 1 January 2021. Studies on the long-term (defined as a mean follow-up of approximately 12 months or longer) efficacy and safety outcomes of combined ablation and LAAC were included.

RESULTS

A total of 16 studies comprising 1428 patients were enrolled. The pooled long-term freedom rate from atrial arrhythmia was 0.66 (95% confidence interval [CI]: 0.59-0.71), long-term successful rate sealing of LAAC was 1.00 (95% CI: 1.00-1.00), and ischemic stroke/transient ischemic attack/systemic embolism during follow-up was 0.01 (95% CI: 0.00-0.02). Meanwhile, of the periprocedural adverse events, phrenic nerve palsy, intracoronary air embolus, device embolization, and periprocedural death had a rate of 0.00 (95% CI: 0.00-0.00), procedure-related bleeding events of 0.03 (95% CI: 0.02-0.04), and pericardial effusion requiring or not requiring intervention of 0.00 (95% CI: 0.00-0.01). Moreover, for the long-term adverse events, device dislocation, intracranial bleeding, pericardial effusion requiring or not requiring intervention, and all-cause mortality had a rate of 0.00 (95% CI: 0.00-0.00), device embolization of 0.01 (95% CI: 0.00-0.01), and other bleeding events of 0.01 (95% CI: 0.00-0.03).

CONCLUSION

This meta-analysis suggests that the combined atrial ablation and LAAC is an effective and safe strategy with long-term benefits.

A Review of Biomarkers for Ischemic Stroke Evaluation in Patients With Non-valvular Atrial Fibrillation

Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia worldwide and results in a significantly increased ischemic stroke (IS) risk. IS risk stratification tools are widely being applied to guide anticoagulation treatment decisions and duration in patients with non-valvular AF (NVAF). The CHA₂DS₂-VASc score is largely validated and currently recommended by renowned guidelines. However, this score is heavily dependent on age, sex, and comorbidities, and exhibits only moderate predictive power. Finding effective and validated clinical biomarkers to assist in personalized IS risk evaluation has become one of the promising directions in the prevention and treatment of NVAF. A number of studies in recent years have explored differentially expressed biomarkers in NVAF patients with and without IS, and the potential role of various biomarkers for prediction or early diagnosis of IS in patients with NVAF. In this review, we describe the clinical application and utility of AF characteristics, cardiac imaging and electrocardiogram markers, arterial stiffness and atherosclerosis-related markers, circulating biomarkers, and novel genetic markers in IS diagnosis and management of patients with NVAF. We conclude that at present, there is no consensus understanding of a desirable biomarker for IS risk stratification in NVAF, and enrolling these biomarkers into extant models also remains challenging. Further prospective cohorts and trials are needed to integrate various clinical risk factors and biomarkers to optimize IS prediction in patients with NVAF. However, we believe that the growing insight into molecular mechanisms and in-depth understanding of existing and emerging biomarkers may further improve the IS risk identification and guide anticoagulation therapy in patients with NVAF.

The risk and severity of stroke in patients with atrial fibrillation and gout: A National Representative Database study

BACKGROUND

It has been shown that gout is associated with left atrium remodeling and a pro-inflammatory state leading to the development of atrial fibrillation (AF). There is limited evidence whether gout increases the risk of stroke in patients with AF. We assessed the incidence of gout and the risk of stroke in patients with AF.

METHODS

This is a retrospective cohort study using the 2016 US National Inpatient Sample (NIS) based on ICD-10 codes. The outcomes of the study were the risk and severity of new stroke in patients with pre-existing AF and gout.

RESULTS

In 2016, we identified 3 844 057 patients admitted to the hospitals in NIS with history of AF, of which 240 875 had history of gout. Patients with AF and gout have higher risk of new stroke (OR 2.07 [1.97-2.19], P < .001), and this risk remains significantly elevated after adjusting for CHADS2VASC score variables, chronic kidney disease, dyslipidemia, obesity, and race (OR 1.10 [1.01-1.11], P = .041). However, presence of gout in patients with AF was not associated with all-cause in-hospital mortality, need for mechanical ventilation, percutaneous gastrostomy tube insertion, or discharge to skilled nursing facility.

CONCLUSION

Subjects with AF and gout compared to AF alone had an increased risk of new stroke, but presence of gout was not associated with stroke severity. There is a potential role of gout as a risk factor or a risk marker for stroke in subjects with AF.

The Key Role of Uric Acid in Oxidative Stress, Inflammation, Fibrosis, Apoptosis, and Immunity in the Pathogenesis of Atrial Fibrillation

Atrial fibrillation (AF) is a highly prevalent cardiac arrhythmia that leads to numerous adverse outcomes including stroke, heart failure, and death. Hyperuricemia is an important risk factor that contributes to atrium injury and AF, but the underlying molecular mechanism remains to be elucidated. In this review, we discussed the scientific evidence for clarifying the role of hyperuricemia in the pathogenesis of AF. Experimental and Clinical evidence endorse hyperuricemia as an independent risk factor for the incidence of AF. Various in vivo and in vitro investigations showed that hyperuricemia might play a critical role in the pathogenesis of AF at different UA concentrations through the activation of oxidative stress, inflammation, fibrosis, apoptosis, and immunity.

CHA2DS2-VASc Score as a Predictor for Left Atrial Thrombus or Spontaneous Echo Contrast in Patients with Nonvalvular Atrial Fibrillation: A Meta-Analysis

Objective

This meta-analysis aimed at exploring the predictive value of CHA₂DS₂-VASc score for the left atrial thrombus (LAT) or left atrial spontaneous echo contrast (LASEC) in patients with nonvalvular atrial fibrillation (NVAF).

Methods

PubMed, Embase, Web of Science, ScienceDirect, Cochrane Library, and Chinese core journals of the CNKI and Wanfang databases were searched to identify all the relevant papers that were published up to January 2020. The data were extracted for pooled odds ratios (ORs) with 95% confidence intervals (CIs), heterogeneity, subgroup, publication bias, and sensitivity analysis.

Results

Overall, 15 studies containing 6223 patients with NVAF were enrolled. All studies were evaluated for LAT, and 12 studies were evaluated for LASEC. The pooled analysis using a random-effects model showed that a high CHA₂DS₂-VASc score was related with LAT/LASEC (pooled OR = 1.59, 95% CI: 1.35–1.88, P < 0.001) with high heterogeneity (I² = 76.9%, P < 0.001) and LAT (pooled OR = 1.83, 95% CI: 1.44–2.33, P < 0.001) with high heterogeneity (I² = 79.4%, P < 0.001). The subgroup analysis demonstrated that the sample size may be the main source of heterogeneity. Although the Begg's funnel plot based on 15 studies for LAT/LASEC (P = 0.029) and 12 studies for LAT (P = 0.046) indicated the presence of publication bias among the included studies, the trim-and-fill method verified the stability of the pooled outcomes. In addition, sensitivity analysis indicated that all effects were stable.

Conclusion

The results of this meta-analysis showed that the CHA₂DS₂-VASc score is related with LAT and LASEC in patients with NVAF. However, more studies are warranted to address this issue.

New perspective on the risk markers for left atrial thrombosis in patients with atrial fibrillation

BACKGROUND

Anticoagulant therapy is one of the important aspects of atrial fibrillation (AF) management, which can effectively reduce the formation of left atrial thrombosis (LAT) and the occurrence of embolic events. The CHA2DS2-VASc score is a commonly used risk assessment tool for embolic events, and it has guiding significance for anticoagulant therapy. However, a large number of recent studies have clearly shown that some of the markers that are not included in the score affect the formation of LAT.

OBJECTIVE

This single-center study probed for risk markers for LAT by analyzing the clinical features of patients who experienced AF.

METHODS

We reviewed patients with AF who had undergone a transesophageal echocardiography exam over the past 6 years and used binary logistic regression analysis to identify risk markers other than CHA2DS2-VASc score. For the risk markers found, the propensity score matching (PSM) was used to further evaluate whether it was an independent risk marker for LAT. The newly discovered markers were added to the score, and receiver operating characteristic analysis was used to evaluate whether the ability of the model to predict LAT was improved.

RESULTS

A total of 2246 patients were included in the study. In total, 838 of them were anticoagulated (314 with rivaroxaban, 57 with dabigatran, and 467 with warfarin) and 30 patients (1.33%) had LAT. Regression analysis revealed abnormal uric acid metabolism (abUA) and obesity were risk markers for LAT. Further PSM analysis found that abUA was an independent risk marker for LAT. After including abUA, the CHA2DS2-VASc score was more accurate for LAT prediction (area under the curve difference is 0.0651, 95% confidence interval: 0.0247, 0.1050, Z = 3.158, P = 0.0016).

CONCLUSIONS

AbUA is an independent risk marker for LAT. After considering abUA, the CHA2DS2-VASc score for LAT is more accurate.

Usefulness of Triglyceride-glucose Index for estimating Hyperuricemia risk: Insights from a general Population

Objectives: Hyperuricemia is a metabolic abnormality that has cast an enormous burden on global healthcare. Previous studies have revealed the close association between insulin resistance and hyperuricemia. Therefore, monitoring insulin sensitivity may be a possible way to prevent hyperuricemia. Recent studies have demonstrated the usefulness of triglyceride-glucose index (TyG) as a simple surrogate of insulin resistance. Hence, our study aimed to explore the impact of TyG on hyperuricemia and its value to improve the risk stratification and prevention of hyperuricemia. Methods: This cross-sectional study included 6466 subjects (mean age: 59.57 years, 60.19% females) from northeast China between September 2017 to May 2018. TyG was determined as ln[fasting TG(mg/dL)×FPG(mg/dL)/2]. Hyperuricemia was defined as serum uric acid ≥ 357 μmol/L for females and ≥ 417 μmol/L for males. Results: The prevalence of hyperuricemia was 5.24%. In the full model, each SD increment of TyG caused a 12.528 μmol/L elevation of serum urate concentration and a 54.1% additional risk for hyperuricemia. When dividing TyG into quartiles, the top quartile had a 2.730 times risk for hyperuricemia than the bottom one. Moreover, smooth curve fitting demonstrated this association was linear. Additionally, subgroup analysis revealed the association was robust to several risk factors of hyperuricemia. Finally, AUC displayed an improvement when introducing TyG into clinical risk factors (0.751 vs 0.772, p < 0.001), category-free net reclassification index (0.304, 95% CI: 0.195-0.413, P < 0.001) and integrated discrimination index (0.009, 95% CI: 0.004-0.013, P < 0.001) also showed the improvement from TyG. Conclusion: Our work revealed the linear and robust association between TyG and hyperuricemia. Furthermore, our results suggest the importance of simultaneous glycemic and lipids control in the prevention of hyperuricemia. Most importantly, our findings implicate the value of TyG to optimize the risk stratification and prevention of hyperuricemia.

Invasive therapies for patients with concomitant heart failure and atrial fibrillation

Atrial fibrillation (AF) and heart failure (HF) are two clinical entities that can present either separately or concurrently. One entity can lead to the other and vice versa as AF can not only be the underlying etiology of HF but also exacerbate HF due to other cardiac diseases. Besides prevention of cerebral and systemic embolism and elimination of AF-related symptoms, restoration of sinus rhythm for AF patients helps to avoid or reduce HF, irrespective of their underlying heart disease. Successful rates of medical therapy for AF are low in persistent AF, and much lower in long-standing AF, while invasive procedures for AF yield promising results. In this review, the authors evaluate the value of invasive therapies for HF patients complicated with non-valvular AF. We examine this clinical problem by interpreting the relationships between these two entities: the mechanism of tachycardia-induced cardiomyopathy (TIC), past opinions about rhythm control and rate control of AF, discrimination of HF-related AF and AF-induced HF, how to identify the AF patients that could benefit from invasive therapies, and how to select invasive therapies for different AF patients and peri-operative treatments.

Atrial fibrillation and type 2 diabetes: Prevalence, etiology, pathophysiology and effect of anti-diabetic therapies

New-onset atrial fibrillation (NAF) is increased in the type 2 diabetic patient because of the presence of the metaboli syndrome and increased sympathetic activity. This results in inflammation, endothelial dysfunction and myocardial steatosis which, in turn, lead to atrial fibrosis and dilatation. The end result is the development of structural and electrical atrial remodeling. Drugs that lower insulin resistance, particularly pioglitazone, decrease the incidence of NAF while drugs that, through hypoglycaemia, stimulate the sympathetic nervous system, insulin and secretagogues, increase the incidence of NAF. Currently there is no evidence that GLP-1 agonists, SGLT2 inhibitors and DPP-4 inhibitors either accelerate or decelerate the development of NAF.

Predictive value of red cell distribution width on left atrial thrombus or left atrial spontaneous echo contrast in patients with non-valvular atrial fibrillation

OBJECTIVE

To evaluate the predictive value of red cell distribution width (RDW) on left atrial thrombus (LAT) or left atrial spontaneous echo contrast (LASEC) in patients with non-valvular atrial fibrillation (AF).

METHODS

We reviewed 692 patients who were diagnosed as non-valvular AF and underwent transesophageal echocardiography (TEE) in Guangdong Cardiovascular Institute from April 2014 to December 2015. The baseline clinical characteristics, laboratory test of blood routine, electrocardiograph measurements were analyzed.

RESULTS

Eighty-four patients were examined with LAT/LASEC under TEE. The mean RDW level was significantly higher in LAT/LASEC patients compared with the non-LAT/LASEC patients (13.59% ± 1.07% vs. 14.34% ± 1.34%; P < 0.001). Receiver-operating characteristic curve analysis was performed and indicated the best RDW cut point was 13.16%. Furthermore, multivariate logistic regression analysis indicated that RDW level > 13.16% could be an independent risk factor for LAT/LASEC in patients with AF.

CONCLUSION

Elevated RDW level is associated with the presence of LAT/LASEC and could be with moderate predictive value for LAT/LASEC in patients with non-valvular AF.