Left Atrial Stiffness: A Predictor of Atrial Fibrillation Recurrence after Radiofrequency Catheter Ablation - A Systematic Review and Meta-Analysis

Left atrial calcification on chest CT: atrial ablation replaces rheumatic heart disease as the most identified etiology

Purpose

Left atrial calcification (LAC), a primarily radiologic diagnosis, has been associated with rheumatic heart disease (RHD) and rheumatic fever (RF). However, left atrial calcification continues to be observed despite a significant decrease in the prevalence of rheumatic heart disease. The purpose of this study was to investigate other possible etiologies of left atrial calcification.

Material and methods

This retrospective, observational single-center study included patients from 2017 to 2022 identified as having left atrial calcification as well as age- and sex-matched controls. The prevalence of rheumatic heart disease, atrial ablation, and mitral valve disease was compared, and odds ratios were calculated for each independent variable.

Results

Sixty-two patients with left atrial calcifications were included and compared with 62 controls. 87.1% of patients in the left atrial calcifications cohort had a history of atrial fibrillation compared with 21% in the control cohort (p < 0.001). 16.1% of patients in the calcifications cohort presented a history of rheumatic fever compared with zero in the control cohort (p = 0.004). 66.1% of the left atrial calcifications cohort had a history of atrial ablation compared with 6.5% of the control group (p < 0.001). The odds ratio for left atrial calcification was 19.0 vs. 4.8 for rheumatic fever (comparative odds = 4.0 for atrial ablation vs. rheumatic fever). Multivariable log model found atrial ablation to explain 79.8% of left atrial calcifications identified.

Conclusions

Our study found a 4-fold higher association between history of atrial ablation and left atrial calcification compared with rheumatic heart disease, suggesting a potential shift in etiology.

Personalized biomechanical insights in atrial fibrillation: opportunities & challenges

INTRODUCTION

Atrial fibrillation (AF) is an increasingly prevalent and significant worldwide health problem. Manifested as an irregular atrial electrophysiological activation, it is associated with many serious health complications. AF affects the biomechanical function of the heart as contraction follows the electrical activation, subsequently leading to reduced blood flow. The underlying mechanisms behind AF are not fully understood, but it is known that AF is highly correlated with the presence of atrial fibrosis, and with a manifold increase in risk of stroke.

AREAS COVERED

In this review, we focus on biomechanical aspects in atrial fibrillation, current and emerging use of clinical images, and personalized computational models. We also discuss how these can be used to provide patient-specific care.

EXPERT OPINION

Understanding the connection betweenatrial fibrillation and atrial remodeling might lead to valuable understanding of stroke and heart failure pathophysiology. Established and emerging imaging modalities can bring us closer to this understanding, especially with continued advancements in processing accuracy, reproducibility, and clinical relevance of the associated technologies. Computational models of cardiac electromechanics can be used to glean additional insights on the roles of AF and remodeling in heart function.

Role of Cardiovascular Magnetic Resonance in the Management of Atrial Fibrillation: A Review

Atrial fibrillation (AF) is the most common arrhythmia, and its prevalence is growing with time. Since the introduction of catheter ablation procedures for the treatment of AF, cardiovascular magnetic resonance (CMR) has had an increasingly important role for the treatment of this pathology both in clinical practice and as a research tool to provide insight into the arrhythmic substrate. The most common applications of CMR for AF catheter ablation are the angiographic study of the pulmonary veins, the sizing of the left atrium (LA), and the evaluation of the left atrial appendage (LAA) for stroke risk assessment. Moreover, CMR may provide useful information about esophageal anatomical relationship to LA to prevent thermal injuries during ablation procedures. The use of late gadolinium enhancement (LGE) imaging allows to evaluate the burden of atrial fibrosis before the ablation procedure and to assess procedural induced scarring. Recently, the possibility to assess atrial function, strain, and the burden of cardiac adipose tissue with CMR has provided more elements for risk stratification and clinical decision making in the setting of catheter ablation planning of AF. The purpose of this review is to provide a comprehensive overview of the potential applications of CMR in the workup of ablation procedures for atrial fibrillation.

Stiff Left Atrium Syndrome After Atrial Fibrillation Ablation – A Diagnosis Not To Forget

Atrial fibrillation is the most prevalent arrhythmia in clinical practice and has different strategies for its control. Of these strategies, the percutaneous ablation of the pulmonary veins stands out, with robust results in relation to drug treatment. It is an invasive procedure and, therefore, not free from complications, which must be properly diagnosed and treated. Among the possible complications, there is stiff atrium syndrome, characterized by reduced atrial compliance caused by post-ablation fibrosis, which, in turn, leads to atrial filling dysfunction and the consequent increase in atrial and venous capillary pulmonary pressures. The case report demonstrates this infrequent but important complication, which presents good results for clinical treatment, in addition to the contribution of cardiac magnetic resonance in its diagnosis and in the assessment of arrhythmia recurrence rates.

Regional Diversities in Fibrogenesis Weighed as a Key Determinant for Atrial Arrhythmogenesis

Atrial fibrosis plays a key role in atrial myopathy, resulting in the genesis of atrial fibrillation (AF). The abnormal distribution of fibrotic tissue, electrical coupling, paracrine interactions, and biomechanical–electrical interactions have all been suggested as causes of fibrosis-related arrhythmogenesis. Moreover, the regional difference in fibrogenesis, specifically the left atrium (LA) exhibiting a higher arrhythmogenesis and level of fibrosis than the right atrium (RA) in AF, is a key contributor to atrial arrhythmogenesis. LA fibroblasts have greater profibrotic cellular activities than RA fibroblasts, but knowledge about the regional diversity of atrial regional fibrogenesis remains limited. This article provides a comprehensive review of research findings on the association between fibrogenesis and arrhythmogenesis from laboratory to clinical evidence and updates the current understanding of the potential mechanism underlying the difference in fibrogenesis between the LA and RA.

Left Atrial Pressure as a Predictor of Success in Catheter Ablation of Atrial Fibrillation in a Real-Life Cohort

Aims: The clinical role of the left atrial (LA) hypertension in patients with atrial fibrillation (AF) and its role as predictor in those undergoing pulmonary vein (PV) isolation is still unknown. The aim of the present study was to analyze the role of LA pressure in patients with nonvalvular AF who underwent PV isolation and its implication for AF catheter ablation. Methods: Consecutive patients with drug resistant AF who underwent PV isolation at San Maurizio Regional Hospital of Bolzano (Italy) as index procedure were included in this analysis. Results: A total of 132 consecutive patients (97 males, 73%; mean age 58.0 ± 13.2 years) were included in the analysis. Eleven patients (8%) underwent radiofrequency ablation and 121 (92%) cryoballoon ablation. Higher LA pressures were found in 54 patients (40.9%). At a mean follow up of 14.3 ± 8.2 months (median 12 months), the success rate without antiarrhythmic therapy was 65.9% (87/132; considering the blanking period). Female gender and continuous mean LA pressure were significantly associated with AF recurrence and remained significant on multivariable Cox analysis (respectively, HR 1.845, 1.00–3.40, p = 0.05 and HR 1.066, 1.002–1.134, p = 0.04). We identified a LA mean pressure of >15 mmHg as ideal cutoff and constructed a model to predict AF recurrence which fitted with a concordance index (C-index) of 0.65 (95% CI 0.56–0.75), logrank score p = 0.003.