Atrial Fibrillation (Part 1): Pathophysiology, Risk Factors, and Therapeutic Basis

Impact of Various Atrial Fibrillation Treatment Strategies on Length of Stay in the Emergency Department and Early Complications-3 Years of a Single-Center Experience

Atrial fibrillation (AF) is the most common arrhythmia presenting in emergency departments (EDs), vastly increasing mainly due to society's lifestyles leading to numerous comorbidities. Its management depends on many factors and is still not unified. Aims: The aim of this study was to compare different AF management strategies in the ED and to evaluate their influence on the length of stay (LOS) in the ED and their safety. We analyzed medical records over 3 years of data collection, including age, primary AF diagnosis, an attempt to restore sinus rhythm, complications, and length of stay. Patients were divided into three groups according to the treatment method received: only pharmacological cardioversion (MED), only electrical cardioversion (EC), and patients who received medications followed by electrical cardioversion (COMB). We included 599 individuals in the analysis with a median age of 71. The restoration of sinus rhythm and LOS were as follows: MED: 64.95%, 173 min; COMB: 87.91%, 295 min; SH: 92.40%, 180 min. The difference between the MED and EC strategies, as well as MED and COMB, was statistically significant (p < 0.001 in both). The total number of complications was 16, with a rate of 32.67%. The majority of them followed a drug administration, and the most common complication was bradycardia. Electrical cardioversion is a safe and effective treatment strategy in stable patients with AF in the ED. It is associated with a shortened LOS. Medication administration preceded the majority of complications.

The role of galectin-3 in patients with permanent and paroxysmal Atrial Fibrillation and echocardiographic parameters of left atrial fibrosis

BACKGROUND

Biochemical markers and imaging tests have been used with the aim of stratifying the risk and detecting atrial fibrosis. Speckle-tracking echocardiography (STE) is used for the detection of atrial fibrosis and Gal-3 provides an important prognostic value. The objective of the study was to assess the association between atrial fibrosis markers and serum levels, genetic polymorphisms and genic expression of galectin-3.

METHODS

206 patients with permanent AF and 70 patients with paroxysmal AF were included in the study. Real time PCR (TaqMan) system was used to study SNPs rs4652 and 4644 of the gene LGALS3. Serum levels of Gal-3 were determined by ELISA and STE was performed to assess fibrosis.

RESULTS

Mean age of individuals with permanent AF was 66.56 ± 12 years. As for the echocardiography results, those patients showed an decrease in the following parameters peak atrial longitudinal strain (PALS) (p = 0.002) when compared to the same parameters from the paroxysmal AF group of patients. There was a correlation between serum levels of Gal-3 and PALS in the group of patients with permanent AF; the lower the levels of gal-3, the lower the LA strain (r = 0.24; p = 0.01).

CONCLUSIONS

Echocardiographic findings showed association with the groups, and with serum levels of Gal-3 in patients with permanent AF. The distribution of allelic and genotypic frequencies, and of the haplotypes of polymorphism LGALS3 rs4652 and rs4644 did not present statistical variation, which suggests that those SNPs are not associated with the AF clinical forms (permanent and paroxysmal).

Atrial Fibrillation in Endurance Training Athletes: Scoping Review

Background

Moderate regular physical activity is indicated to avoid atrial fibrillation (AF), whereas athletes should be counseled that long-lasting vigorous sports engagement may cause AF, according to the 2016 European Society of Cardiology (ESC) recommendations for AF treatment. Exercise and AF are complex.

Objectives

To evaluate the relationship between Endurance training and AF, in addition to the starting point/trigger by which Endurance Training causes impairment of cardiac function and AF, considering the time and intensity of Endurance training.

Materials and Methods

We synthesized evidence from articles published in the PubMed, EMBASE, and SciELO databases using their respective Boolean operators. A total of 112 original articles related to AF and endurance athletes published up to the year 2023 were reviewed.

Results

Our study verified multiples aspects of the genesis of AF in athletes, such as cardiac adaptations to exercise, disturbances in cardiac injury biomarkers, sex differences in cardiac adaptations and their role in AF risk, and the relationship between body composition (height, weight, and physical fitness) and AF pathogenesis.

Conclusions

Variations in cardiac structure (increased atrial thickness and size in addition to myocardial fibrosis) and significant increases in vagal tone (sinus bradycardia and imbalances in sympathetic and parasympathetic activation) shorten the refractory period shortening in athletes, induce the onset of re-entrance mechanisms, and serve as ectopic triggers that can lead to AF.

Circulating MicroRNAs as Specific Biomarkers in Atrial Fibrillation: A Meta-Analysis

Atrial fibrillation (AF) is the most frequently occurring supraventricular arrhythmia. Although microRNAs (miRNAs) have been associated with AF pathogenesis, standard protocols for quantifying and selecting specific miRNAs for clinical use as biomarkers should be optimized. In this study, we evaluated the clinical application of miRNAs as biomarkers for the prognosis and diagnosis of AF. Literature searches were conducted on PubMed, Cochrane Library, and EMBASE. We included prospective or retrospective observational studies that had been published as of 14 February 2022; our main objective was to analyze the relationship between circulating miRNAs and AF. The data were extracted using the descriptors "Atrial fibrillation AND miRNA", "Atrial fibrillation AND diagnostic AND miRNA", and "Atrial fibrillation AND prognosis AND miRNA". No filters were applied for period delimitation, type of publication, or language. Studies using samples isolated from blood plasma and TaqMan and RT-qPCR for detecting and quantifying miRNAs were selected, and those that used atrial tissue samples were excluded. We identified 272 articles and excluded 102 duplicated articles. Two authors independently read the titles and abstracts of 170 out of 272 articles and selected 56 potential articles, 6 of which were selected for final review. Our analysis revealed a significant association between AF and miR-4798 [OR = 1.90 (95% CI 1.45-2.47)], AF and miRNA-133a [2.77 (2.73-2.82)], AF and miRNA-150 [3.77 (1.50-9.46); I² = 70%], AF and miRNA-21 [2.23 (1.20-4.17); I² = 99%], AF and hsa-miRNA4443 [2.32 (2.20-2.44)], and AF and miR-20a-5p [3.67 (1.42-9.49)]. The association between miRNAs and AF showed an OR of 2.51 [95% CI 1.99-3.16; I² = 99%]. Our meta-analysis demonstrated that circulating miRNAs are potential biomarkers of AF, as they exhibit stable expression post-sample collection. In addition to regulating cellular processes, such as proliferation, differentiation, development, and cell death, miRNAs were found to be linked to arrhythmia development.

Polysonographic changes in obese patients with indication of bariatric surgery

INTRODUCTION

obstructive Sleep Apnea Syndrome (OSAS) is a serious confition that compromises the quality of life and survival of patients. Its main risk fator in adults is obesity and the gold standard test for diagnosis is polysomnography (PSG), mainly through the apneia-hypopnea index (AHI). Objective: to analyze the sleep pattern of obese patients with indication for bariatric surgery, determining the main polisomnographic parameters compromised by obesity.

METHODS

This work is a cross-sectional study with analysis of polysomnography perfomed in patients with obesity in the peroperative period of bariatric surgery at a clinic in Vitória da Conquista/BA during 2017. The Epi Info 7 platform was used for analysis of the data.

RESULTS

58 polysomnographic reports were analyzed, with 56,9% morbdly obese and 43,1% non-morbid. The prevalence of OSAS was 70,68% and de AHI ranged from zero to 84,6 with a mean of 19,47±22,89 e/h. morbidly obese, compared to "non-morbid", had a longer saturation time below 80% and 90% (0,4±0,93 vs. 0,12±0,45 e 4,87±7,38 vs. 1,36±2,87 respectively; p-value=0,02 in both), worse index respiratory disorders ((29,24±25,36 vs. 16,88±16,21; p-value=0,02), higher AHI (24,71±25,68 vs. 12,56±16,67; p-value=0,02), higher hypopnea index values (16,41±17,10 vs. 6,99±8,52; p-value=0,006) and lower minimum saturation (78,24±9,80 vs. 85,24±6,33; p-value=0,004).

CONCLUSIONS

the high prevalence of OSAS found confirms its indication in the preoperative period of bariatric surgery. The main respiratory event involved in most individuals with OSAS was the hypopnea index.