The efficacy of glucocorticoids for the prevention of atrial fibrillation, or length of intensive care unite or hospital stay after cardiac surgery: a meta-analysis

Compartmentalization proteomics revealed endolysosomal protein network changes in a goat model of atrial fibrillation

Endolysosomes (EL) are known for their role in regulating both intracellular trafficking and proteostasis. EL facilitate the elimination of damaged membranes, protein aggregates, membranous organelles and play an important role in calcium signaling. The specific role of EL in cardiac atrial fibrillation (AF) is not well understood. We isolated atrial EL organelles from AF goat biopsies and conducted a comprehensive integrated omics analysis to study the EL-specific proteins and pathways. We also performed electron tomography, protein and enzyme assays on these biopsies. Our results revealed the upregulation of the AMPK pathway and the expression of EL-specific proteins that were not found in whole tissue lysates, including GAA, DYNLRB1, CLTB, SIRT3, CCT2, and muscle-specific HSPB2. We also observed structural anomalies, such as autophagic-vacuole formation, irregularly shaped mitochondria, and glycogen deposition. Our results provide molecular information suggesting EL play a role in AF disease process over extended time frames.

The neutrophil-to-lymphocyte ratio is a potential biomarker for the occurrence of atrial fibrillation in patients with obstructive sleep apnea: A BIOMARKER OF AF IN OSA PATIENTS

BACKGROUND

Obstructive sleep apnea (OSA) affects the occurrence of atrial fibrillation (AF) and usually coexists with AF. Chronic inflammation has been identified as an important factor in the development of AF, and the neutrophil-to-lymphocyte ratio (NLR) has been identified as a biomarker that positively correlates with the degree of inflammation. However, little information regarding how NLR correlates with AF in OSA patients.

METHODS

Our study enrolled 368 patients with OSA between September 2018 and April 2023. All data were collected after admission. Independently associated factors were assessed by multivariate logistic regression and then constructed a nomogram to predict AF risk. Nomogram's calculation model was evaluated using receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis (DCA). The correlation between CHA2DS2-VASc scores and NLR was assessed using Spearman correlation.

RESULTS

Multivariate logistic regression showed that high level log-transformed NLR (OR, 1.664; 95% CI, 1.026-2.699; P = 0.039) was independently associated with the presence of AF in patients with OSA. The concordance index (0.817, 95% CI, 0.770-0.864), ROC curve, calibration curve, and DCA of the nomogram indicated this model had well clinical utility. Also, the nomogram's calculation model could identify patients who are at a higher risk of developing AF, and the CHA2DS2-VASc score was positively correlated with NLR in patients with AF (P < 0.05).

CONCLUSION

The elevated NLR may serve as a promising biomarker for assessing the risk of AF in individuals with OSA. The nomogram's calculation model may be utilized as a tool to estimate the probability of AF occurrence in OSA patients.

Risk and protective factors for atrial fibrillation after cardiac surgery and valvular interventions: an umbrella review of meta-analyses

Objective

Postoperative atrial fibrillation (POAF) is a common complication affecting approximately one-third of patients after cardiac surgery and valvular interventions. This umbrella review systematically appraises the epidemiological credibility of published meta-analyses of both observational and randomised controlled trials (RCT) to assess the risk and protective factors of POAF.

Methods

Three databases were searched up to June 2021. According to established criteria, evidence of association was rated as convincing, highly suggestive, suggestive, weak or not significant concerning observational studies and as high, moderate, low or very low regarding RCTs.

Results

We identified 47 studies (reporting 61 associations), 13 referring to observational studies and 34 to RCTs. Only the transfemoral transcatheter aortic valve replacement (TAVR) approach was associated with the prevention of POAF and was supported by convincing evidence from meta-analyses of observational data. Two other associations provided highly suggestive evidence, including preoperative hypertension and neutrophil/lymphocyte ratio. Three associations between protective factors and POAF presented a high level of evidence in meta-analyses, including RCTs. These associations included atrial and biatrial pacing and performing a posterior pericardiotomy. Nineteen associations were supported by moderate evidence, including use of drugs such as amiodarone, b-blockers, glucocorticoids and statins and the performance of TAVR compared with surgical aortic valve replacement.

Conclusions

Our study provides evidence confirming the protective role of amiodarone, b-blockers, atrial pacing and posterior pericardiotomy against POAF as well as highlights the risk of untreated hypertension. Further research is needed to assess the potential role of statins, glucocorticoids and colchicine in the prevention of POAF.

PROSPERO registration number

CRD42021268268.

Patient periprocedural stress in cardiovascular medicine: friend or foe?

Stress, a disruption of homeostasis, is an unavoidable part of everyday life. In medical procedures, stress profoundly affects both operators and patients. Although the stress reaction has evolved to aid survival of physical trauma, it may also be harmful, by aggravating the baseline medical condition and/or creating new stress-related medical problems. Stress responses comprise several protective mechanisms that are particularly relevant in the clinical setting (e.g., a procoagulatory state and blood loss counteraction, preservation of blood perfusion pressure, prevention of hypoglycemia, enhanced immune response). Beneficial psychological effects prevent recurrence of traumatic memories, and promote patient compliance and positive lifestyle changes. In contrast, overt acute stress responses may lead to severe pathological conditions such as cytokine storm, post-traumatic stress disorder, takotsubo syndrome, deep venous thrombosis and pulmonary embolism, myocardial infarction, life-threatening arrhythmias and sudden cardiac death. There is also evidence that stress exposure may promote atherosclerosis and reduce long-term benefits from the intervention (increase in major adverse clinical events, in-stent restenosis, etc.). Insights into the role of stress on the operator’s performance have recently led to the introduction of counteractive measures such as simulation training. Conversely, very little is known about the effect of the patient’s periprocedural stress on the outcomes of cardiovascular procedures. Recent data show that the patient periprocedural stress affects the well-being of whole families. This review, focused on topics particularly relevant to cardiovascular interventions, provides a mechanistic insight into beneficial and harmful effects of periprocedural patient stress, including the array of available stress-relieving measures.

Molecular Insights in Atrial Fibrillation Pathogenesis and Therapeutics: A Narrative Review

The prevalence of atrial fibrillation (AF) is bound to increase globally in the following years, affecting the quality of life of millions of people, increasing mortality and morbidity, and beleaguering health care systems. Increasingly effective therapeutic options against AF are the constantly evolving electroanatomic substrate mapping systems of the left atrium (LA) and ablation catheter technologies. Yet, a prerequisite for better long-term success rates is the understanding of AF pathogenesis and maintenance. LA electrical and anatomical remodeling remains in the epicenter of current research for novel diagnostic and treatment modalities. On a molecular level, electrical remodeling lies on impaired calcium handling, enhanced inwardly rectifying potassium currents, and gap junction perturbations. In addition, a wide array of profibrotic stimuli activates fibroblast to an increased extracellular matrix turnover via various intermediaries. Concomitant dysregulation of the autonomic nervous system and the humoral function of increased epicardial adipose tissue (EAT) are established mediators in the pathophysiology of AF. Local atrial lymphomononuclear cells infiltrate and increased inflammasome activity accelerate and perpetuate arrhythmia substrate. Finally, impaired intracellular protein metabolism, excessive oxidative stress, and mitochondrial dysfunction deplete atrial cardiomyocyte ATP and promote arrhythmogenesis. These overlapping cellular and molecular alterations hinder us from distinguishing the cause from the effect in AF pathogenesis. Yet, a plethora of therapeutic modalities target these molecular perturbations and hold promise in combating the AF burden. Namely, atrial selective ion channel inhibitors, AF gene therapy, anti-fibrotic agents, AF drug repurposing, immunomodulators, and indirect cardiac neuromodulation are discussed here.

Posterior pericardiotomy to prevent new-onset atrial fibrillation after coronary artery bypass grafting: a systematic review and meta-analysis of 10 randomized controlled trials

BACKGROUND

Atrial fibrillation (AF) is associated with adverse events after cardiac surgery. Multiple studies have reported that posterior pericardiotomy (PP) may be effective for preventing AF after coronary artery bypass grafting (CABG), but some conflicting results have been reported and the quality of evidence from previous meta-analyses has been limited. The present study aimed to systematically evaluate the safety and efficacy of PP for preventing AF after CABG in adults.

METHODS

We conducted a quantitative meta-analysis of randomized controlled trials (RCTs) published before May 31, 2021. The primary outcome was AF after CABG under cardiopulmonary bypass. Secondary outcomes included early pericardial effusion, late pericardial effusion, pericardial tamponade, pleural effusion, length of hospital stay, length of intensive care unit (ICU) stay, pulmonary complications, intra-aortic balloon pump use, revision surgery for bleeding, and mortality.

RESULTS

Ten RCTs with 1829 patients (910 in the PP group and 919 in the control group) were included in the current meta-analysis. The incidence of AF was 10.3% (94/910) in the PP group and 25.7% (236/919) in the control group. A random-effects model indicated that incidence of AF after CABG significantly lower in the PP group than in the control group (risk ratio = 0.45, 95% confidence interval 0.29-0.64, P < 0.0001). PP also effectively reduced the post-CABG occurrence of early pericardial effusion (RR = 0.28, 95% CI 0.15-0.50; P < 0.05), late pericardial effusion (RR = 0.06, 95% CI 0.02-0.16; P < 0.05), and pericardial tamponade (RR = 0.08, 95% CI 0.02-0.33; P < 0.05) as well as the length of ICU stay (weighted mean difference [WMD] = 0.91,95% CI 0.57-1.24; P < 0.05), while increasing the occurrence pleural effusion (RR = 1.51, 95% CI 1.19-1.92; P < 0.05). No significant differences length of hospital stay (WMD =  - 0.45, 95% CI - 2.44 to 1.54, P = 0.66), pulmonary complications (RR = 0.99, 95% CI 0.71-1.39, P = 0.97), revision surgery for bleeding (RR = 0.84, 95% CI 0.43-1.63, P = 0.60), use of IABP (RR = 1, 95% CI 0.61-1.65, P = 1.0), or death (RR = 0.45, 95% CI 0.07-3.03, P = 0.41) were observed between the PP and control groups.

CONCLUSIONS

PP may be a safe, effective, and economical method for preventing AF after CABG in adult patients.

Effects of corticosteroids on new-onset atrial fibrillation after cardiac surgery: A meta-analysis of randomized controlled trials

BACKGROUND

Postoperative atrial fibrillation (POAF) occurs commonly after cardiac surgery. Studies suggest that corticosteroid can reduce the incident of POAF. However, the results remain controversial. This meta-analysis aimed to evaluate the efficacy and safety corticosteroid on the prevention of POAF following cardiac surgery.

METHODS

Randomized controlled trials were identified through a systematic literature search. Two investigators independently searched articles, extracted data, and assessed the quality of included studies. Primary outcome was the incidence of POAF as well as length of hospital stay and intensive care unit stay, wound and other infection, mortality, duration of ventilation, myocardial infarction, gastrointestinal complications, high blood sugar, stroke, and postoperative bleeding.

RESULTS

Fourteen studies with 13,803 patients were finally involved in the present study. Overall, corticosteroid significantly decreased the risk of POAF (relative risk [RR], 0.7; 95% confidence interval [CI], 0.55-0.89; P = .003). There were no significant differences in the incidence of length of intensive care unit stay (RR, -2.32; 95% CI, -5.44 to 0.80; P = .14) and hospital stay (RR, -0.43; 95% CI, -0.84 to -0.02; P = .04), infections (RR, 1.01; 95% CI, 0.83-1.23; P = .9), mortality (RR, 0.87; 95% CI, 0.71-1.06; P = .16), duration of ventilation (RR, -0.29; 95% CI, -0.65 to 0.07; P = .12), gastrointestinal complications (RR, 1.26; 95% CI, 0.91-1.76; P = .16), high blood sugar (RR, 1.98; 95% CI, 0.91-4.31; P = .09), stroke (RR, 0.9; 95% CI, 0.69-1.18; P = .45), postoperative bleeding (RR -44.54; 95% CI, -115.28 to 26.20; P = .22) and myocardial infarction (RR, 1.71; 95% CI, 0.96-1.43; P = .12).

CONCLUSION

Our review suggests that the efficacy of corticosteroid might be beneficial to POAF development in patients undergoing cardiac surgery. The strength of this association remains uncertain because of statistical and clinical heterogeneity among the included studies.

Atrial fibrillation type modulates the clinical predictive value of neutrophil-to-lymphocyte ratio for atrial fibrillation recurrence after catheter ablation

BACKGROUND

The neutrophil-to-lymphocyte ratio (NLR) has been proposed as an indicator of a systemic inflammatory response. There are baseline differences in the inflammation status between paroxysmal atrial fibrillation (PAF) and persistent AF (PerAF). The NLR changes and late recurrences of AF (LRAF) after ablation depending on the AF type remain unknown.

METHODS

Consecutive AF patients undergoing pulmonary vein isolation (PVI) by radiofrequency catheter ablation were enrolled from September 2014 to June 2018. The peripheral blood leukocyte NLR 1 day before and 36-48 h after PVI were measured. First, the relationship between NLR changes after to before ablation (ΔNLR) and ERAFs/LRAFs in PAF and PerAF patients were investigated to exclude the baseline inflammation status and evaluate catheter ablation induced inflammation. Second, the clinical impact of the NLR for predicting LRAFs was evaluated.

RESULTS

There hundred sixty-nine PAF and 264 PerAF patients from Osaka Rosai AF registry were enrolled. The ratio of ERAFs/LRAFs in PAF and PerAF patients were 26.8%/22.5% and 39.4%/29.9%, respectively. In PAF and PerAF patients, the ΔNLR was significantly higher with ERAF than no-ERAF (p = 0.022 and p = 0.010, respectively). In PAF patients, the ΔNLR was significantly higher with LRAF than no-LRAF (p = 0.017), while with PerAF, the ΔNLR did not significantly differ between LRAFs and no-LRAFs. In PAF, the ΔNLR was independently and significantly associated with LRAFs after PVI (p = 0.029).

CONCLUSION

The ΔNLR was significantly higher only in PAF patients with LRAFs than no-LRAFs, but not in PerAF patients. The ΔNLR was useful for predicting LRAFs after PVI in PAF patients.

Systematic review of pre-clinical therapies for post-operative atrial fibrillation

BACKGROUND

Post-operative atrial fibrillation (POAF) is a frequent cardiothoracic surgery complication that increases hospital stay, mortality and costs. Despite decades of research, there has been no systematic overview and meta-analysis of preclinical therapies for POAF in animal models.

METHODS

We performed a systematic search of MEDLINE and EMBASE from their inception through September 2020 to determine the effect of preclinical POAF therapies on primary efficacy outcomes using a prospectively registered protocol (CRD42019155649). Bias was assessed using the SYRCLE tool and CAMARADES checklist.

RESULTS

Within the 26 studies that fulfilled our inclusion criteria, we identified 4 prevention strategies including biological (n = 5), dietary (n = 2), substrate modification (n = 2), and pharmacological (n = 17) interventions targeting atrial substrate, cellular electrophysiology or inflammation. Only one study altered more than 1 pathophysiological mechanism. 73% comprised multiple doses of systemic therapies. Large animal models were used in 81% of the studies. Preclinical therapies altogether attenuated atrial fibrosis (SMD -2.09; 95% confidence interval [CI] -2.95 to -1.22; p < 0.00001; I2 = 47%), AF inducibility (RR 0.40; 95% CI 0.21 to 0.79; p = 0.008; I2 = 39%), and AF duration (SMD -2.19; 95% CI -3.05 to -1.32; p < 0.00001; I2 = 50%). However, all the criteria needed to evaluate the risk of bias was unclear for many outcomes and only few interventions were independently validated by more than 1 research group.

CONCLUSION

Treatments with therapies targeting atrial substrate, cellular electrophysiology or inflammation reduced POAF in preclinical animal models compared to controls. Improving the quality of outcome reporting, independently validating promising approaches and targeting complimentary drivers of POAF are promising means to improve the clinical translation of novel therapies for this highly prevalent and clinically meaningful disease.

Inflammatory and Infectious Processes Serve as Links between Atrial Fibrillation and Alzheimer's Disease

Atrial fibrillation (AF) is one of the most prevalent forms of arrhythmia that carries an increased risk of stroke which, in turn, is strongly associated with cognitive decline. The majority of dementia cases are caused by Alzheimer's disease (AD) with obscure pathogenesis. While the exact mechanisms are unknown, the role of inflammatory processes and infectious agents have recently been implicated in both AD and AF, suggesting a common link between these maladies. Here, we present the main shared pathways underlying arrhythmia and memory loss. The overlapping predictive biomarkers and emerging joint pharmacological approaches are also discussed.

Pharmacological Inhibition of Serine Proteases to Reduce Cardiac Inflammation and Fibrosis in Atrial Fibrillation

Systemic inflammation correlates with an increased risk of atrial fibrillation (AF) and thrombogenesis. Systemic inflammation alters vessel permeability, allowing inflammatory and immune cell migration toward target organs, including the heart. Among inflammatory cells infiltrating the atria, macrophages and mast cell have recently attracted the interest of basic researchers due to the pathogenic mechanisms triggered by their activation. This chemotactic invasion is likely implicated in short- and long-term changes in cardiac cell-to-cell communication and in triggering fibrous tissue accumulation in the atrial myocardium and electrophysiological re-arrangements of atrial cardiomyocytes, thus favoring the onset and progression of AF. Serine proteases are a large and heterogeneous class of proteases involved in several processes that are important for cardiac function and are involved in cardiac diseases, such as (i) coagulation, (ii) fibrinolysis, (iii) extracellular matrix degradation, (iv) activation of receptors (i.e., protease-activated receptors [PPARs]), and (v) modulation of the activity of endogenous signals. The recognition of serine proteases substrates and their involvement in inflammatory/profibrotic mechanisms allowed the identification of novel cardio-protective mechanisms for commonly used drugs that inhibit serine proteases. The aim of this review is to summarize knowledge on the role of inflammation and fibrosis as determinants of AF. Moreover, we will recapitulate current findings on the role of serine proteases in the pathogenesis of AF and the possible beneficial effects of drugs inhibiting serine proteases in reducing the risk of AF through decrease of cardiac inflammation and fibrosis. These drugs include thrombin and factor Xa inhibitors (used as oral anticoagulants), dipeptidyl-peptidase 4 (DPP4) inhibitors, used for type-2 diabetes, as well as novel experimental inhibitors of mast cell chymases.

Anti-inflammatory drugs in the prevention of post-operative atrial fibrillation: a literature review

Atrial fibrillation (AF) is a serious and common complication following heart surgery. Cardiac surgery triggers inflammation in the heart and makes it susceptible to the incidence of AF. Therefore, anti-inflammatory drugs may reduce the rate of AF incidence in the post-surgery conditions. Immunosuppressant agents, steroidal anti-inflammatory drugs (corticosteroids), non-aspirin non-steroid anti-inflammatory drugs (NSAIDs), colchicine and omega-3 unsaturated fatty acids (n-3 UFA) are drugs with well-known anti-inflammatory properties. The efficacy, safety and other aspects of using these drugs in the prevention of post-operative AF (POAF) have been reviewed here. Studies evaluating the efficacy of colchicine have shown that it could be effective in the prevention of POAF. However, there is a need for additional studies to find a colchicine regimen with optimal efficacy and higher tolerability. The use of corticosteroids may also be of value based on the most of meta-analyses. In the case of n-3 polyunsaturated fatty acids and NSAIDs, current data fail to support their efficacy in POAF prevention. Moreover, perioperative administration of NSAIDs may be associated with some severe safety considerations. Immunosuppressant agents have not been used for the prevention of POAF. Further studies are needed to find the most effective strategy for POAF prevention with the least safety considerations and the highest health benefits.

Inflammation and atrial fibrillation: A comprehensive review

Atrial fibrillation (AF) has different underlying substrates. Atrial remodeling involves electrophysiological and structural abnormalities that promote the development and perpetuation of AF. Experimental and clinical data indicate that inflammation is implicated in the pathophysiology of atrial remodeling. The mechanistic links between atrial remodeling and inflammation are complex while diverse underlying diseases and conditions may affect these pathways. Inflammatory markers have also been associated with AF development, recurrence, perpetuation, total AF burden as well as with thromboembolic complications. The development of specific anti-inflammatory interventions in this setting seems to be challenging and complicated. Several agents with pleiotropic properties, including anti-inflammatory, have been tested in experimental and clinical settings with variable results. This updated review provides a concise overview of all available data regarding the role of inflammation in AF including the predictive role of inflammatory markers. Also, current knowledge and future directions on anti-inflammatory strategies are critically discussed.

Oxidant and Inflammatory Mechanisms and Targeted Therapy in Atrial Fibrillation: An Update

Atrial fibrillation (AF) is an important cause of stroke and risk factor for heart failure and death. Current pharmacologic treatments for AF have limited efficacy, and treatments that more directly target the underlying causes of AF are needed. Oxidant stress and inflammatory activation are interrelated pathways that promote atrial electrical and structural remodeling, leading to atrial ectopy, interstitial fibrosis, and increased stroke risk. This review evaluates the impact of common stressors on atrial oxidant stress and inflammatory activation and the contribution of these pathways to atrial remodeling. Recent studies suggest that integrated efforts to target the underlying risk factors, rather than the AF per se, may have a greater impact on health and outcomes than isolated efforts focused on the electrical abnormalities.

Vitamin C for the Prevention of Postoperative Atrial Fibrillation after Cardiac Surgery: A Meta-Analysis

PURPOSE

Several studies have investigated the administration of vitamin C (vitC) for the prevention of postoperative atrial fibrillation (AF) after cardiac surgery. However, their findings were inconsistent. The purpose of this meta-analysis was to evaluate the efficacy of vitC as prophylaxis for the prevention of postoperative AF in cardiac surgery.

METHODS

A systematic search of PubMed, EMBASE, Google Scholar, the Cochrane Library, and clinical trial registries, was performed. 9 studies, published from August 2001 to May 2015, were included, with a total of 1,037 patients. Patients were randomized to receive vitC, or placebo.

RESULTS

Cardiac surgery patients who received vitC as prophylaxis, had a significantly lower incidence of postoperative AF (random effects OR=0.478, 95% CI 0.340 - 0.673, P < 10(-4)). No significant heterogeneity was detected across the analyzed studies (I(2)=21.7%), and no publication bias or other small study-related bias was found.

CONCLUSION

Our findings suggest that VitC is effective as prophylaxis for the prevention of postoperative AF. The administration of vitC may be considered in all patients undergoing cardiac surgery.

Statin therapy in the primary prevention of early atrial fibrillation after coronary artery bypass grafting

OBJECTIVE

Assessment of the role of statin therapy in the prevention of postoperative atrial fibrillation (POAF) after coronary artery bypass grafting (CABG) in patients without prior atrial fibrillation.

METHODS

A retrospective analysis of 206 patients, aged 57.2±7.9 years (mean±SD), who underwent isolated CABG is carried out. All patients are divided into two groups. The first group (nSt-patients) includes the patients who did not receive statin therapy prior to CABG (n=82). The second group (St-patients) includes the patients who received statin therapy prior to CABG (n=124). Both groups received the statin therapy from the first day after CABG. The risk of occurrence of POAF is evaluated using the Cox-regression model.

RESULTS

The rate of POAF was 25.6% in nSt-patients and 6.5% in St-patients (P=0.020). On the 4th day after CABG, white blood cells (WBC) count was 11.0 (9.0, 13.0)×10⁹/mL (medians with inter-quartile ranges) in nSt-patients and 9.0 (7.6, 10.2)×10⁹/mL in St-patients (P<0.001). The peak WBC numbers occurred on the day of POAF onset. The Cox-regression analysis shows that only two factors (statin therapy and number of grafts) had significant influence on the POAF onset. Odds ratio of POAF event prediction by statin therapy was 0.20 (95%CI: 0.08-0.51), P<0.001. Each subsequent graft increased the risk of POAF in 2.1 times.

CONCLUSION

Statin therapy carried out prior to the CABG is an effective approach to primary prevention of POAF in early postoperative period. Statin therapy after CABG in nSt-patients does not give prophylactic effect observed in St-patients.