Inflammation, oxidative stress and postoperative atrial fibrillation in cardiac surgery

GTS-21 alleviates sepsis-induced atrial fibrillation susceptibility by modulating macrophage polarization and Neuregulin-1 secretion

OBJECTIVE

Sepsis-induced atrial fibrillation (AF) is driven by systemic inflammation and macrophage-mediated atrial remodeling, with proinflammatory M1 macrophages playing a key role. This study investigates whether GTS-21, an α7nAChR agonist, can reduce AF susceptibility by promoting macrophage polarization towards the anti-inflammatory M2 phenotype.

METHODS

A mouse model of lipopolysaccharide (LPS) (10 mg/kg)-induced sepsis was used to explore the relationship between atrial inflammation and AF. GTS-21 (20 mg/kg) was administered to assess its impact on 48-h survival and AF incidence. Cardiac function was evaluated using echocardiography. Markers of myocardial injury, including CK-MB, LDH, and cTnI, were measured. Macrophage polarization and atrial inflammation were assessed using immunofluorescence, flow cytometry, RT-qPCR, and western blotting. Oxidative stress and mitochondrial function were evaluated using reactive oxygen species (ROS) measurements, electron microscopy, and mitochondrial protein expression analysis. Calcium dynamics were studied using western blotting and confocal microscopy.

RESULTS

In LPS-induced septic mice, GTS-21 improved 48-h survival rates and reduced the induction rate and duration of AF (P < 0.05). Echocardiography showed a preserved left ventricular ejection fraction and enhanced diastolic function. Mechanistically, it promoted M2 macrophage polarization, inhibited the NF-κB P65/NLRP3/C-caspase 1 pathway to reduce IL-1β release, and alleviated oxidative stress. Additionally, mitochondrial structure was restored by reversing fission and promoting fusion, while calcium-handling proteins (NCX-1, RYR2, and SERCA2a) were regulated to prevent intracellular calcium overload, reducing AF susceptibility.

CONCLUSION

GTS-21 mitigated atrial inflammation and reduced the incidence of AF in mice with sepsis by regulating macrophage polarization, reducing oxidative stress, and preserving mitochondrial and calcium dynamics in cardiomyocytes. These findings highlight the therapeutic potential of GTS-21 in treating sepsis-induced AF.

Tracking inflammation status for improving patient prognosis: A review of current methods, unmet clinical needs and opportunities

Inflammation is the body's response to infection, trauma or injury and is activated in a coordinated fashion to ensure the restoration of tissue homeostasis and healthy physiology. This process requires communication between stromal cells resident to the tissue compartment and infiltrating immune cells which is dysregulated in disease. Clinical innovations in patient diagnosis and stratification include measures of inflammatory activation that support the assessment of patient prognosis and response to therapy. We propose that (i) the recent advances in fast, dynamic monitoring of inflammatory markers (e.g., cytokines) and (ii) data-dependent theoretical and computational modeling of inflammatory marker dynamics will enable the quantification of the inflammatory response, identification of optimal, disease-specific biomarkers and the design of personalized interventions to improve patient outcomes - multidisciplinary efforts in which biomedical engineers may potentially contribute. To illustrate these ideas, we describe the actions of cytokines, acute phase proteins and hormones in the inflammatory response and discuss their role in local wounds, COVID-19, cancer, autoimmune diseases, neurodegenerative diseases and aging, with a central focus on cardiac surgery. We also discuss the challenges and opportunities involved in tracking and modulating inflammation in clinical settings.

Effects of Midazolam and Dexmedetomidine on Cognitive Dysfunction Following Open-Heart Surgery: A Comprehensive Review

PURPOSE

Patients undergoing open-heart surgery often face significant challenges in postoperative cognitive dysfunction (POCD). There has been growing interest in understanding how anesthesia medications, such as dexmedetomidine (DEX) and midazolam, impact cognitive function in these patients.

METHOD

This comprehensive review aims to detail the effect of DEX and midazolam on cognitive outcomes following open-heart surgery.

FINDINGS

Midazolam, a highly selective and commonly used benzodiazepine for preoperative anxiolytics and sedation has been associated with POCD. However, evidence regarding its impact on cognitive function is vague; some studies suggest a potential link between midazolam administration and cognitive impairment, while others report no effect or even an improvement in cognitive abilities. DEX is a potential neuroprotective agent in cardiac surgery. The effects of DEX on cognitive function, including a reduction in POCD incidence and severity, have been reported in several studies. It modulates the inflammatory responses, attenuates oxidative stress, and preserves cerebral perfusion. Although DEX and midazolam show promising results, their effects on cognitive function following open-heart surgery are yet to be elucidated.

CONCLUSION

Various factors, including patient characteristics, perioperative management, and surgical procedures, may influence these outcomes, highlighting the need for further research to better understand the roles of these agents in cognitive function following open-heart surgery.

Methylene blue reduces monoamine oxidase expression and oxidative stress in human cardiovascular adipose tissue

Cardiovascular diseases represent the major cause of morbidity mainly due to chronic heart failure. Epicardial (EAT) and perivascular adipose tissues (PVAT) are considered major contributors to the pathogenesis of cardiometabolic pathologies. Monoamine oxidases (MAOs) are mitochondrial enzymes recognized as sources of reactive oxygen species (ROS) in cardiometabolic pathologies. Methylene blue (MB) is one of the oldest protective agents, yet no data are available about its effects on adipose tissue. The present pilot study was aimed at assessing the effects of MB: (i) on MAO expression and (ii) oxidative stress in EAT and PVAT harvested from patients with heart failure subjected to cardiac surgery (n = 25). Adipose tissue samples were incubated with MB (0.1 µM/24 h) and used for the assessment of MAO gene and protein expression (qPCS and immune fluorescence) and ROS production (confocal microscopy and spectrophotometry). The human cardiovascular adipose tissues contain both MAO isoforms, predominantly MAO-A. Incubation with MB reduced MAOs expression and oxidative stress; co-incubation with serotonin, the MAO-A substrate, further augmented ROS generation, an effect partially reversed by MB. In conclusion, MAO-A is the major isoform expressed in EAT and PVAT and contribute to local oxidative stress; both effects can be mitigated by methylene blue.

Heart failure with reduced ejection fraction developed from valvular surgery: Risk factors and therapeutic effects of sacubitril valsartan

Objective

To investigate the risk factors for heart failure developed from cardiac valvular surgery and the efficacy of sacubitril valsartan (ARNI).

Methods

Clinical data from patients with left ventricular ejection fraction (LVEF) ≥ 50 % who consecutively underwent cardiac valvular (mitral/aortic valve) surgery in 2021 were collected. Pre - and intra - operative variables were analyzed to explore risk factors for HFrEF (LVEF ≤ 40 %). Post - operative HFrEF patients were split into ARNI - treated (n = 15) and non-ARNI - treated (n = 15) groups. Follow - up echocardiography data were compared to assess ARNI's efficacy.

Results

Among 420 patients undergoing valve surgery (117 aortic, 133 mitral, 170 double-valve), 34 (8.1 %) developed HFrEF, showing significantly higher in-hospital mortality than non-HFrEF patients (8.82 % vs 0.52 %). Multivariate analysis identified preoperative left ventricular diameter as an independent HFrEF risk factor. During follow-up, 70 % of HFrEF patients achieved LVEF > 50 % within 6 months, Repeated-measures F test demonstrated significantly greater LVEF improvement (P = 0.036) and LVEDD reduction (P = 0.014) in the ARNI group versus non-ARNI group.

Conclusions

About 8 % of patients with LVEF ≥ 50 % developed HFrEF after cardiac valvular surgery, and large left ventricular diameter was an independent risk factor. Sacubitril valsartan is very effective in improving left ventricular remodeling and LVEF in such cohort.

Clinical characteristics and prognostic implication of atrial fibrillation in the postoperative period of cardiac surgery with cardiopulmonary bypass

INTRODUCTION

Despite the latest innovations in surgical and cardiopulmonary bypass techniques, atrial fibrillation remains a common occurrence in patients undergoing heart surgery, and has been shown to increase the incidence of intra- and postoperative complications. For this reason, it is among the top 10 research topics in cardiovascular surgery.

METHOD

Observational, analytical, retrospective study carried out at the largest cardiovascular centre in Mexico. Adult patients (>18 years) with no history of atrial fibrillation who underwent on-pump heart surgery between 1 January 2022 and 31 December 2023 were included. Variables that have previously been correlated with postoperative atrial fibrillation (POAF) were evaluated.

RESULTS

A total of 544 patients were included. The incidence of POAF was 23.8%. Overall in-hospital mortality was 5.9%. There was a significant difference in age between patients that developed postoperative atrial fibrillation and those that maintained sinus rhythm (62 years vs 57 years, p = < 0.01). Using a univariate logistic regression model, we found that POAF significantly predicts the occurrence of hospital-acquired pneumonia (OR 3.12, 95% CI 1.61-6.02, p = <0.01) and the requirement for renal replacement therapy (OR 3.04, 95% CI 1.34-6.86, p = <0.01).

CONCLUSIONS

Atrial fibrillation is a common arrhythmia in the postoperative period of on-pump heart surgery, and is a predictor of adverse outcomes. Prevention, early detection and treatment of POAF may have prognostic implications.

Relevance of Targeting Oxidative Stress, Inflammatory, and Pro-Resolution Mechanisms in the Prevention and Management of Postoperative Atrial Fibrillation

Atrial fibrillation (AF) is the most common cardiac arrhythmia. AF can lead to severe complications, including stroke, myocardial infarction, and sudden death. AF risk factors include pathological aging and conditions such as obesity, diabetes, and hypertension. Clinical data revealed that cardiothoracic and non-cardiothoracic surgeries are also important risk factors for AF. Post-operative AF (POAF) is associated with important public health costs caused by increased hospitalization, frequent emergency room visits, and enhanced healthcare utilization, which altogether lead to a low quality of life for the patients. Hence, POAF is a major clinical challenge, and there is an urgent need for the development of novel therapeutic strategies. Interestingly, evidence from clinical and fundamental research converges to identify cardiac oxidative stress and atrial inflammation as the common denominators of all AF risk factors. Unresolved inflammation is suspected to provoke cardiac fibrosis, which is an important contributor to cardiac arrhythmias and AF. Antioxidant, anti-inflammatory, and pro-resolution strategies may help to combat post-operative cardiac remodeling and POAF. This article aims to review the current scientific evidence supporting the role of inflammation in the pathogenesis of POAF and explore potential novel therapeutic strategies to prevent and mitigate inflammation in the management of AF.

Phenylephrine and the risk of atrial fibrillation in critically ill patients: a multi-centre study from eICU database

Background

Vasopressors are vital for maintaining blood pressure in critically ill patients, though they carry risks like irregular heartbeats and impaired cardiac oxygen balance. Existing studies have not definitively proven that phenylephrine triggers new atrial fibrillation (AF).

Aims

This study was designed to assess pharmacological associations between phenylephrine utilization and new AF occurrence risk.

Methods

This multicenter retrospective study analyzed eICU database records. Propensity score matching (PSM) balanced baseline confounders. Cox regression models (unadjusted/adjusted) assessed phenylephrine-AF associations.

Results

In this cohort encompassing 51,294 critically ill adults (mean age 62.4 ± 16.6 years; 53.5% male), propensity score matching established comparable cohorts: 2,110 phenylephrine-exposed patients and 6,330 matched controls. The analysis revealed a clinically significant disparity in new AF incidence, with phenylephrine-exposed patients demonstrating a 10.5% event rate (282/2,673) versus 4.9% (2,395/48,621) in non-exposed counterparts (p < 0.001). Multivariable-adjusted Cox proportional hazards models identified a 29% elevated risk of new AF associated with phenylephrine administration (aHR, 1.29; 95%CI, 1.05-1.58). Notably, this association remained robust across multiple sensitivity analyses employing alternative matching methodologies and covariate adjustments.

Conclusion

This evidence positions phenylephrine as a modifiable new AF risk factor in critical care, supporting risk-aware vasopressor selection through benefit-harm analysis.

A Review on the Etiologies of the Development of Atrial Fibrillation After Cardiac Surgery

Postoperative atrial fibrillation (POAF) is the most common arrhythmia following cardiac surgery. This review critically explores the interplay between cardiopulmonary bypass (CPB) and aortic cross-clamping (ACC) times in POAF development. CPB disrupts systemic homeostasis by inducing inflammatory cascades, oxidative stress, and ischemia-reperfusion injury. Prolonged ACC times further exacerbate myocardial ischemia and structural remodeling, with durations exceeding 60-75 min consistently linked to an increased POAF risk. However, variability in outcomes across studies reveals the complex, multifactorial nature of POAF pathogenesis. Patient-specific variables, such as baseline comorbidities and myocardial protection strategies, modulate these risks, emphasizing the need for personalized surgical approaches. Despite advancements in myocardial protection techniques and anti-inflammatory strategies, the incidence of POAF remains persistently high, indicating a gap in translating mechanistic insights into effective interventions. Emerging biomarkers, including microRNAs (e.g., miR-21, miR-483-5p, etc.) and markers of myocardial injury like troponin I, offer potential for enhanced risk stratification and targeted prevention. However, their clinical applicability requires further validation in diverse patient populations. This review underscores the critical need for integrative research that combines clinical, molecular, and procedural variables to elucidate the nuanced interplay of factors driving POAF. Future directions include leveraging advanced intraoperative monitoring tools, refining thresholds for CPB and ACC times, and developing individualized perioperative protocols.

Retained blood syndrome after cardiac surgery

OBJECTIVES

Retained blood syndrome (RBS) is defined as the postoperative retention of blood within the thoracic cavity. In addition to the mechanical impacts on cardiac and pulmonary function, RBS triggers inflammatory processes. It is associated with increased morbidity following cardiac surgery. The goal of this non-systematic review was to summarize the current understanding of the pathophysiology, consequences and both prophylactic and therapeutic measures related to RBS.

METHODS

The subjects to be covered were defined in advance. A literature search was conducted in PubMed and Google Scholar using relevant search terms and MeSH terms.

CONCLUSIONS

RBS is a significant complication following cardiac surgical procedures. It is associated with a poorer prognosis due to mechanical suppression of haemodynamics and the amplification of inflammatory processes. Therefore, preventing pericardial and pleural effusions should be a priority in cardiac surgical care. If RBS occurs, aggressive anti-inflammatory therapy should be initiated to prevent the development of long-term complications.

Hypertension and Atrial Fibrillation: Bridging the Gap Between Mechanisms, Risk, and Therapy

Background and objectives: Atrial fibrillation (AF), the most prevalent sustained arrhythmia, poses a significant public health challenge due to its links with stroke, heart failure, and mortality. Hypertension, a primary modifiable cardiovascular risk factor, is a well-established risk factor for AF that facilitates structural and electrical changes in the atria, including dilation, fibrosis, and pressure overload. Material and Methods: we conducted a literature search regarding the shared mechanisms, risks and treatments of hypertension and atrial fibrillation. Results: The renin-angiotensin-aldosterone system plays a pivotal role in this remodelling and inflammation, increasing AF susceptibility. Uncontrolled hypertension complicates AF management, diminishing the effectiveness of mainstay treatments, including antiarrhythmic drugs, catheter ablation, and cardioversion. Effective blood pressure management, particularly with therapies targeting the renin-angiotensin-aldosterone system (RAAS), can lower the risk of new-onset AF and reduce the incidence of recurrent AF, enhancing the success of rhythm control strategies. These antihypertensive therapies mitigate myocardial hypertrophy and fibrosis and attenuate both atrial pressure strain and the inflammatory response, mitigating the substrates for AF. Conclusion: This review highlights the urgent need for integrated strategies that combine BP control, AF screening, and lifestyle modifications to minimise the burden of AF and its complications. Future research should investigate the specific mechanisms of cellular-level interactions associated with a hypertensive predisposition to AF, including systematic inflammation and the role of genetics, the impact of blood pressure variations on AF risk, and individualised treatment strategies specifically targeting the shared mechanisms, simultaneously propagating hypertension and AF.

Comparison of midazolam and dexmedetomidine combined with thoracic paravertebral block in hemodynamics, inflammation and stress response, and cognitive function in elderly lung cancer patients

OBJECTIVE

This study aimed to compare the clinical outcomes of midazolam and dexmedetomidine combined with ropivacaine-induced thoracic paravertebral nerve block (TPVB) in radical lung cancer surgery.

METHODS

To retrospectively analyze the clinical data of elderly patients who underwent thoracoscopic radical lung cancer surgery from March 2020 to February 2023 in our hospital. All patients underwent a single two-site method of TPVB at the levels of T4 and T7 under ultrasound guidance. The patients were divided into midazolam group (0.25 % ropivacaine + 0.1 mg/kg midazolam) and dexmedetomidine group (0.25 % ropivacaine + 0.8 μg/kg dexmedetomidine) according to the application of sedative drugs, with 78 cases in each group. Ramsay sedation score, mean arterial pressure (MAP), heart rate (HR), electroencephalographic bispectral index (BIS), and blood oxygen saturation (SpO2), as well as the serum levels of C-reactive protein (CRP), tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), epinephrine (E), cortisol (Cor), and norepinephrine (NE) were recorded at 6, 12, 24, 36 and 48 h postoperatively, respectively. The patients' cognitive function was assessed using the Brief Mental State Evaluation Scale (MMSE) at 1 d preoperatively, 1 d postoperatively, and 7 d postoperatively.

RESULTS

The amount of intraoperative sufentanil in the dexmedetomidine group was lower than that in the midazolam group (P < 0.05). The rate of atropine use was higher in the dexmedetomidine group than that in the midazolam group (P < 0.05). There was no significant difference in the occurrence of overall intraoperative adverse reactions (P > 0.05), but the incidence of respiratory depression in the dexmedetomidine group was significantly lower than that in the midazolam group, and the incidence of bradycardia in the dexmedetomidine group was significantly higher than that in the midazolam group (P < 0.05). At T0 ∼ T4, BIS and MAP showed a decreasing trend in both groups. 12, 24, 36 and 48 h postoperatively, the Ramsay sedation score was higher in the dexmedetomidine group than in the midazolam group (P < 0.05). At 36 and 48 h postoperatively, the serum Cor, E, NE, CRP, TNF-α, and IL-6 levels were lower in the dexmedetomidine group than in the midazolam group (P < 0.05). Compared with the preoperative 1d, the MMSE scores were significantly lower in both groups on one day postoperative, while the MMSE scores were significantly higher at postoperative day 7 than on postoperative day 1 (P < 0.05). At postoperative day 1, the MMSE score was significantly higher in the dexmedetomidine group than in the midazolam group (P < 0.05). The difference in the incidence of adverse events within 72 h postoperatively between the two groups was not statistically significant (3.95 % vs. 1.28 %, χ2 = 0.284, P = 0.594).

CONCLUSION

Dexmedetomidine compounded with ropivacaine-induced ultrasound-guided thoracic paravertebral nerve block is superior to midazolam for sedation, anti-inflammation, and anti-stress in elderly lung cancer patients.

Association between blood test indicators and atrial fibrillation in elderly patients aged 65 and above in the Central Jiangsu region: a cross-sectional study

OBJECTIVES

The aim of this study was to explore the correlation between blood test indicators and Atrial Fibrillation (AF) in Individuals Aged 65 and Older in Yangzhou, Jiangsu.

METHODS

From January 1, 2019, to August 31, 2023, an epidemiological cross-sectional survey was conducted among the elderly population undergoing health check-ups at Northern Jiangsu People's Hospital in Jiangsu Province. Patients diagnosed with AF after a 12-lead electrocardiogram were included in the case group, and non-AF individuals matched by age and gender in a 1:4 frequency ratio were included in the control group. Least Absolute Shrinkage and Selection Operator (LASSO) regression was used to select important variables from routine blood tests and biochemical indicators and their derived indicators (such as TyG, TyG-BMI, TG/HDL-c, RAR, NLR, MHR). Based on the selected variables, participants were divided into four groups (Q1 ~ Q4), and multifactorial Logistic regression analysis, restricted cubic spline regression, gender subgroup analysis and Receiver Operating Characteristic (ROC) curve were used to explore the relationship between the relevant variables and AF.

RESULTS

A total of 5,879 elderly individuals over the age of 65 were included in the study, with a prevalence of AF of 2.96% (174/5,879). The prevalence of AF in the overall population, as well as in male and female populations, showed a continuous increasing trend with age (P for trend < 0.001). A total of 696 individuals without AF after matching served as the control group, and LASSO regression identified albumin, direct bilirubin, and uric acid as three significant indicators. After adjusting for relevant confounding factors, lower levels of albumin, and higher levels of direct bilirubin and uric acid were significantly associated with the occurrence of AF (P < 0.05). Gender subgroup analysis revealed that in the elderly female population, albumin was not significantly associated with AF (P > 0.05), while direct bilirubin and uric acid were significantly associated with AF (P < 0.05). In the male population, albumin, direct bilirubin, and uric acid were significantly associated with AF (P < 0.05). Restricted cubic spline regression analysis showed a significant nonlinear relationship between direct bilirubin and AF (P for nonlinear < 0.001). The ROC curve analysis indicates that albumin, direct bilirubin, and uric acid all have good association strength with AF in elderly patients, with direct bilirubin showing the strongest association effect (AUC (95% CI) = 0.728 (0.686, 0.769)).

CONCLUSIONS

Low levels of albumin, high levels of direct bilirubin, and uric acid are all significantly associated with AF in the elderly population of the Central Jiangsu region. The conclusions of this study need further validation with a larger sample size.

The Association Between Serum Uric Acid Levels and the Risk of Cognitive Dysfunction in Patients With Atrial Fibrillation

Patients with atrial fibrillation (AF) are linked to an increased risk of cognitive dysfunction, and serum uric acid levels play an important factor in cognitive dysfunction. However, the optimal serum uric acid level in patients with AF remains unclear. Therefore, we aimed to explore the relationship between serum uric acid and cognitive dysfunction. 583 patients were conducted in the Affiliated Hospital of Jining Medical University. Cognitive dysfunction was assessed by the Montreal Cognitive Assessment (MoCA). The relationship between serum uric acid levels and the risk of cognitive dysfunction in patients with AF was analyzed using the smoothing spline fitting model and threshold analysis. The average serum uric acid level was (383.26 ± 110.11) μmol/L, and the incidence of cognitive dysfunction was 79.76%. There was a non-linear relationship between serum uric acid levels and the risk of cognitive dysfunction in patients with AF, and the inflection point was 352 μmol/L. At the left of the inflection point, the relationship was significant (OR = 1.02, 95% CI = 1.00-1.04). At the right of the inflection point, there was no statistical difference (p=0.101). When serum uric acid levels are less than 352 μmol/L, the risk of cognitive dysfunction increases by 2% for each unit increase in serum uric acid levels in patients with AF. The study provides evidence for the treatment of serum uric acid levels in patients with AF.

Insight into Cardioprotective Effects and Mechanisms of Dexmedetomidine

PURPOSE

Cardiovascular disease remains the leading cause of death worldwide. Dexmedetomidine is a highly selective α2 adrenergic receptor agonist with sedative, analgesic, anxiolytic, and sympatholytic properties, and several studies have shown its possible protective effects in cardiac injury. The aim of this review is to further elucidate the underlying cardioprotective mechanisms of dexmedetomidine, thus suggesting its potential in the clinical management of cardiac injury.

RESULTS AND CONCLUSION

Our review summarizes the findings related to the involvement of dexmedetomidine in cardiac injury and discusses the results in the light of different mechanisms. We found that numerous mechanisms may contribute to the cardioprotective effects of dexmedetomidine, including the regulation of programmed cell death, autophagy and fibrosis, alleviation of inflammatory response, endothelial dysfunction and microcirculatory derangements, improvement of mitochondrial dysregulation, hemodynamics, and arrhythmias. Dexmedetomidine may play a promising and beneficial role in the treatment of cardiovascular disease.

Catecholamine Vasopressors and the Risk of Atrial Fibrillation After Noncardiac Surgery: A Prospective Observational Study

Background

Catecholamine vasopressors are commonly used for intra- or post-operative hypotension for cardiac surgery, which have a side effect of new-onset atrial fibrillation (AF) and myocardial ischemia. However, it is not entirely clear whether catecholamine vasopressors increase the risk of new-onset AF after noncardiac surgery.

Aim

The aim of this study was to analyze the association between the use of catecholamine vasopressors and the risk of developing new-onset AF after noncardiac surgery.

Methods

In this prospective trial, available data from eligible elderly individuals receiving noncardiac surgery at a single center from November 2022 to January 2024 were gathered. Propensity score matching (PSM) was used to balance patient baseline characteristics and to control for confounders. To determine the association between catecholamine vasopressors and the risk of new-onset AF, univariate and multivariate logistic regression analyses were performed.

Results

A total of 6000 subjects were included in this study (mean [SD] age, 70.73 [6.37] years; 910 [50.9%] males). After PSM, the patients were stratified into catecholamine vasopressor (n = 357) and comparator groups (n = 1432). A total of 18/357 patients in the catecholamine vasopressor group developed AF, and 25/1432 patients in the comparator group developed AF (incidence rate, 5.0% vs 1.7%). Compared with the comparator group, the catecholamine vasopressor group had an increased risk of new-onset AF (aOR, 2.77; 95% CI, 1.28-5.89). Some sensitivity analyses also revealed consistent findings of increased new-onset AF risk associated with catecholamine vasopressor treatment.

Conclusion

The findings from this study suggest that catecholamine vasopressor treatment is associated with an increased risk of new-onset AF and may help physicians select a modest medication for patients while also assessing the risk of new-onset AF.

The Crucial Triad: Endothelial Glycocalyx, Oxidative Stress, and Inflammation in Cardiac Surgery-Exploring the Molecular Connections

Since its introduction, the number of heart surgeries has risen continuously. It is a high-risk procedure, usually involving cardiopulmonary bypass, which is associated with an inflammatory reaction that can lead to perioperative and postoperative organ dysfunction. The extent of complications following cardiac surgery has been the focus of interest for several years because of their impact on patient outcomes. Recently, numerous scientific efforts have been made to uncover the complex mechanisms of interaction between inflammation, oxidative stress, and endothelial dysfunction that occur after cardiac surgery. Numerous factors, such as surgical and anesthetic techniques, hypervolemia and hypovolemia, hypothermia, and various drugs used during cardiac surgery trigger the development of systemic inflammatory response and the release of oxidative species. They affect the endothelium, especially endothelial glycocalyx (EG), a thin surface endothelial layer responsible for vascular hemostasis, its permeability and the interaction between leukocytes and endothelium. This review highlights the current knowledge of the molecular mechanisms involved in endothelial dysfunction, particularly in the degradation of EG. In addition, the major inflammatory events and oxidative stress responses that occur in cardiac surgery, their interaction with EG, and the clinical implications of these events have been summarized and discussed in detail. A better understanding of the complex molecular mechanisms underlying cardiac surgery, leading to endothelial dysfunction, is needed to improve patient management during and after surgery and to develop effective strategies to prevent adverse outcomes that complicate recovery.

Differential Expression of mRNA in Peripheral Blood Mononuclear Cells May Predict Postoperative Atrial Fibrillation in Coronary Artery Bypass Surgery Patients

Postoperative Atrial Fibrillation (POAF) frequently follows Coronary Artery Bypass Grafting (CABG) surgery. This prospective study investigates genes linked to POAF in CABG patients, aiming to create a predictive model. Employing differential gene and methylation analyses, the study identified four genes (WARS2, CKAP2, CHI3L1, HSD17B6) associated with POAF. Preoperative plasma samples and clinical data were collected from 139 CABG patients, categorized into POAF (+) (43) and POAF (-) (96). Real-time quantitative PCR assessed gene expression, and a predictive model using the LASSO method demonstrated robust performance, with AUC values of 0.8895 in the training set and 0.7840 in the test set. This pioneering study integrates genomics and clinical data, suggesting WARS2, CKAP2, and CHI3L1 as potential indicators for POAF prediction.

NBQX mediates ventricular fibrillation susceptibility in rat models of anxiety via the Nrf2/HO-1 pathway

Objective

Anxiety disorder (AD) is a common mental disorder related to cardiovascular disease morbidity. Oxidative stress plays a crucial role in the anxiety state and can lead to cardiac remodeling. Over-activation of the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) in cardiomyocytes and neurons can cause oxidative stress. Additionally, the AMPAR inhibitor-2,3-dihydroxy-6-nitro-7-sulfamoyl-benzoquinoxaline-2,3-dione (NBQX) plays an important role in ameliorating oxidative stress. This study aimed to explore the anti-arrhythmic effects of NBQX in a rat model of anxiety.

Methods

The AD model was induced using empty bottle stimulation. Male Sprague Dawley rats were randomly divided into four groups: control + saline, control + NBQX, AD + saline, and AD + NBQX. Open field test was conducted to measure anxiety-like behavior. Electrophysiological experiments, histological analysis, biochemical detection and molecular biology were performed to verify the effects of NBQX on the amelioration of electrical remodeling and structural remodeling. Furthermore, the nuclear factor erythroid 2-related factor 2 (Nrf2) inhibitor (ML385) was used in vitro to demonstrate the signaling pathway.

Results

Oxidative stress levels increased with AMPAR over-activation in AD rats, leading to heightened vulnerability to ventricular fibrillation (VF). NBQX reverses anxiety and VF susceptibility. Our results showed that NBQX activated the Nrf2/heme oxygenase-1 (HO-1) pathway, leading to a decline in oxidative stress levels. Connexin 43 and ion channel expression was upregulated. NBQX treatment attenuated fibrosis and apoptosis. This effect was diminished by ML385 treatment in vitro.

Conclusion

NBQX can alleviate VF susceptibility in rat models of anxiety by alleviating electrical remodeling, structural remodeling via regulating the Nrf2/HO-1 pathway to some extent.

Better prognosis in surgical aortic valve replacement patients with lower red cell distribution width: A MIMIC-IV database study

BACKGROUND

Surgical aortic valve replacement (SAVR) currently stands as a primary surgical intervention for addressing aortic valve disease in patients. This retrospective study focused on the role of the red blood cell distribution width (RDW) in predicting adverse outcomes among SAVR patients.

METHODS

The subjects for this study were exclusively derived from the Medical Information Mart for Intensive Care database (MIMIC IV 2.0). Kaplan‒Meier (K-M) curves and Cox proportional hazards regression models were employed to assess the correlation between RDW, one-year mortality, and postoperative atrial fibrillation (POAF). The smooth-fitting curves were used to observe the relative risk (RR) of RDW in one-year mortality and POAF. Furthermore, time-dependent receiver operating characteristic (ROC) curves, the continuous-net reclassification index (NRI), and integrated discrimination improvement (IDI) were employed for comprehensive assessment of the prognostic value of RDW.

RESULTS

Analysis of RDW revealed a distinctive inverted U-shaped relationship with one-year mortality, while its association with POAF appeared nearly linear. Cox multiple regression models showed that RDW > 14.35%, along with preoperative potassium concentration and perioperative red blood cell transfusion, were significantly linked to one-year mortality (K-M curves, log-rank P < 0.01). Additionally, RDW was associated with both POAF and prolonged hospital stays (P < 0.05). There was no significant difference in length of stay in ICU. Notably, the inclusion of RDW in the predictive models substantially enhanced its performance. This was evidenced by the time-dependent ROC curve (AUC = 0.829), NRI (P< 0.05), IDI (P< 0.05), and K-M curves (log-rank P< 0.01).

CONCLUSIONS

RDW serves as a robust prognostic indicator for SAVR patients, offering a novel means of anticipating adverse postoperative events.

Effects of Heart Failure Therapies on Atrial Fibrillation: Biological and Clinical Perspectives

Heart failure (HF) and atrial fibrillation (AF) are prevalent cardiovascular diseases that contribute significantly to morbidity, mortality, hospitalisation, and healthcare costs. It is not uncommon for these conditions to coexist and have mutually reinforcing effects. A critical factor in the aetiology of these conditions is oxidative stress, driven by reactive oxygen species (ROS), which contributes to atrial remodelling and fibrosis. The recent introduction of new drugs for the treatment of heart failure has also had an impact on the management of atrial fibrillation due to their influence on oxidative stress. The objective of this review is to analyse the effects of these therapies, including their role in mitigating ROS, on the prevention and treatment of AF in HF patients.

Relationships between Interleukin 18 -607 C/A and -137 G/C, Osteopontin -9250 C/T Genetic Polymorphisms and Systemic Inflammatory Response Syndrome in Coronary Artery Bypass Graft Surgery

Background and Objectives: Systemic inflammatory response syndrome (SIRS) is one of the most significant complications after on-pump heart surgery procedures. High cytokine levels have been shown after open-heart surgeries and a genetic predisposition seems to be an important underlying modulatory characteristic for SIRS. To investigate the association between interleukin 18 -607 C/A, interleukin 18 -137 G/C and osteopontin 9250 C/T genetic polymorphisms and SIRS in on-pump CABG patients. Materials and Methods: Two hundred consecutive elective on-pump CABG patients were recruited prospectively to the study. Genomic DNA was extracted from whole blood and genotyping was determined by sequence specific PCR or PCR-RFLP methods for related polymorphisms. Results: SIRS incidence was 60.2%, 38.1%, 18.9% on postoperative day 1, 2 and 3, respectively, in the whole study population. The SIRS rate on the second postoperative day was 13% and 43.4%, respectively, in osteopontin 9250 C/T T allele non-carriers and carriers (p = 0.004). WBC (White Blood Cell) counts were higher on day 2 and 3 in osteopontin 9250 C/T T allele carriers compared to non-carriers (day 2; 12.7 ± 4 vs. 10.5 ± 2.4 (p = 0.015), day 3; 11.8 ± 4 vs. 9.1 ± 4.7 (p = 0.035)). The average ICU stay was 3.1 ± 7.4, 1.28 ± 0.97 for IL 18-137 G/C C allele carriers and non-carriers, respectively (p = 0.003), and in the IL 18-137 G/C C allele carriers, SIRS developed in 42.2% by the second postoperative day whereas the rate was 57.8% in non-carriers (p = 0.025). Conclusions: The current research revealed a possible link between osteopontin 9250 C/T and IL18-137 G/C genetic polymorphism and SIRS and morbidity in on-pump CABG patients.

Association of systemic inflammatory markers with postoperative arrhythmias in esophageal cancer: a propensity score matching

BACKGROUND

The severity and prognosis of an array of inflammatory diseases have been predicted using systemic inflammatory indices, such as the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio, lymphocyte-to-monocyte ratio (LMR), derived neutrophil-to-lymphocyte ratio (dNLR), and systemic immune inflammation index (SII). The purpose of this study was to examine the association between systemic inflammatory markers and postoperative arrhythmias (PA) in esophageal cancer patients.

METHODS

In the study, laboratory-related parameters were gathered and examined in 278 patients (non-PA = 221, PA = 57). Fit separate propensity score matching (PSM) within subgroup strata (surgery approaches); match within strata, and aggregate for main analysis. Finally, we established a 1:1(57:57) model. The ability of inflammatory makers on the first post-esophagectomy day to distinguish PA from postoperative non-arrhythmia (non-PA) by receiver operating characteristic (ROC) analysis.

RESULTS

On the first post-esophagectomy day, there was a greater difference between PA and non-PA in terms of white blood cell (WBC) and neutrophil (NE), Neutrophil percentage (NE%), NLR, dNLR, LMR, and SII. After PSM, the following variables were substantially different between non-PA and PA: NE%, NLR, dNLR, and SII. It was found that WBC, NE, NE%, NLR, dNLR, LMR, and SII had the area under the curve (AUC) that was higher than 0.500 in ROC analysis, with NLR and SII having the highest AUC (AUC = 0.661). The indicators were subjected to binary logistic regression analysis, which increased the indicators' predictive ability (AUC = 0.707, sensitivity = 0.877).

CONCLUSION

On the first post-esophagectomy day, systemic inflammatory indicators were significantly correlated with both PA and non-PA, and high SII and NLR are reliable markers of PA.

Preoperative ultrasound-guided bilateral thoracic erector spinae plane block within an enhanced recovery program is associated with decreased intraoperative lactate levels in cardiac surgery

INTRODUCTION

In the perioperative period, regional analgesia techniques may play an increasingly important role in "Enhanced Recovery After Surgery (ERAS)" programs, as they can facilitate recovery. We hypothesized that Erector Spinae Plane (ESP) block could improve regional perfusion, thereby limiting blood lactate increase. Therefore, we aimed to evaluate the effect of ESP block on intraoperative blood lactate levels in patients scheduled for elective on-pump cardiac surgery with ERAS protocol.

METHODS

A total of 68 adult patients scheduled for on-pump cardiac surgery were included. All patients were randomized to the ESP group and the non-ESP group. Blood lactate analyses were performed at intraoperative five-time points. C-Reactive protein (CRP) values were also measured.

RESULTS

Blood lactate values were significantly lower in the ESP group than in the Non-ESP group, at the end of CPB [1.78 (1.23-2.78) mmol L-1 to 2.63 (1.70-3.12) mmol L-1] and during the sternal closure period [1.78 (1.27-2.42) mmol L-1 to 2.40 (2.14-2.80) mmol L-1] (p = 0.039, p = 0.009). In addition, CRP values were significantly lower in the ESP group in the postoperative period [0.048 (0.036-0.105) g L-1 to 0.090 (0.049-0.154) g L-1] (p = 0.035).

CONCLUSIONS

This study showed that preoperative bilateral single-shot ESP block significantly reduces intraoperative final blood lactate and postoperative CRP values. We consider that these results are related to the attenuation of intraoperative hypoperfusion and the alleviation of surgery-related postoperative inflammation. ERAS programs aim to achieve the rapid recovery of patients, a decrease in inflammation, and high-quality analgesia with less opioid consumption. Therefore, our results also prove that it is easier to reach the primary goals of ERAS programs with the application of ESP block in cardiac surgery.

Prolonged Systemic Inflammatory Response Syndrome After Cardiac Surgery

OBJECTIVES

Cardiac surgery induces systemic inflammatory response syndrome (SIRS), leading to higher morbidity and mortality. There are no individualized predictors for worse outcomes or biomarkers for the multifactorial, excessive inflammatory response. The interest of this study was to evaluate whether a systematic use of the SIRS criteria could be used to predict postoperative outcomes beyond infection and sepsis, and if the development of an exaggerated inflammation response could be observed preoperatively.

DESIGN

The study was observational, with prospectively enrolled patients.

SETTING

This was a single institution study in a hospital setting combined with laboratory findings.

PARTICIPANTS

The study included a cohort of 261 volunteer patients.

INTERVENTIONS

Patients underwent cardiac surgery with cardiopulmonary bypass, and were followed up to 90 days. Biomarker profiling was run preoperatively.

MEASUREMENTS AND MAIN RESULTS

Altogether, 17 of 261 (6.4%) patients had prolonged SIRS, defined as fulfilling at least 2 criteria on 4 consecutive postoperative days. During hospitalization, postoperative atrial fibrillation (POAF) was found in 42.2% of patients, and stroke and transient ischemic attack in 3.8% of patients. Prolonged SIRS was a significant predictor of POAF (odds ratio [OR] 4.5, 95% CI 1.2-17.3), 90-day stroke (OR 4.5, 95% CI 1.1-18.0), and mortality (OR 10.7, 95% CI 1.7-68.8). Biomarker assays showed that preoperative nerve growth factor and interleukin 5 levels were associated with prolonged SIRS (OR 5.6, 95%, CI 1.4-23.2 and OR 0.7, 95%, CI 0.4-1.0, respectively).

CONCLUSIONS

Nerve growth factor and interleukin 5 can be used to predict prolonged systemic inflammatory response, which is associated with POAF, stroke, and mortality.

Frequency and risk factors of atrial fibrillation after acute abdominal surgery: A prospective cohort study

BACKGROUND AND AIM

Scarce data exist on the true incidence of postoperative atrial fibrillation (POAF) after acute abdominal surgery and associated outcomes. The current study aimed to identify the frequencies of clinically recognized POAF and associated complications, along with their risk factors.

METHODS

This study was a prospective, single-center cohort study of unselected adult patients referred for acute abdominal surgery during a 3-month period. Through careful review, demographics, comorbidity, and surgical characteristics were prospectively drawn from medical charts. The primary outcome was clinically recognized POAF occurring in-hospital. Logistic regression was used to determine the risk factors of POAF and associated complications. A subgroup was enrolled in a feasibility study of peri- and postoperative continuous cardiac rhythm monitoring.

RESULTS

In total, 450 patients were enrolled. Clinically recognized in-hospital POAF was observed in 22 patients (4.9%). All cases were observed in patients aged ≥60 years, corresponding to 22 of 164 patients (13.4%). Multiple risk factors were observed, such as age, prior atrial fibrillation, heart failure, hypertension, diabetes mellitus, chronic renal disease, and major (vs. minor) surgery. POAF was associated with severe in-hospital complications (POAF group 45.5% vs. non-POAF group 8.6%, p < .001) and in-hospital mortality (POAF group 13.6% vs. non-POAF group 3.0%, p = .043). In total, 295 patients were monitored by continuous cardiac rhythm monitoring for 12,148 h, yielding five patients with asymptomatic AF.

CONCLUSIONS

In conclusion, this prospective study of POAF in patients undergoing acute abdominal surgery showed that one in 20 patients developed clinically recognized in-hospital POAF. Multiple risk factors of POAF were identified. POAF was associated with severe complications up to 30 days after surgery.

Effects of RBT-1 on preconditioning response biomarkers in patients undergoing coronary artery bypass graft or heart valve surgery: a multicentre, double-blind, randomised, placebo-controlled phase 2 trial

Background

RBT-1 is a combination drug of stannic protoporfin (SnPP) and iron sucrose (FeS) that elicits a preconditioning response through activation of antioxidant, anti-inflammatory, and iron-scavenging pathways, as measured by heme oxygenase-1 (HO-1), interleukin-10 (IL-10), and ferritin, respectively. Our primary aim was to determine whether RBT-1 administered before surgery would safely and effectively elicit a preconditioning response in patients undergoing cardiac surgery.

Methods

This phase 2, double-blind, randomised, placebo-controlled, parallel-group, adaptive trial, conducted in 19 centres across the USA, Canada, and Australia, enrolled patients scheduled to undergo non-emergent coronary artery bypass graft (CABG) and/or heart valve surgery with cardiopulmonary bypass. Patients were randomised (1:1:1) to receive either a single intravenous infusion of high-dose RBT-1 (90 mg SnPP/240 mg FeS), low-dose RBT-1 (45 mg SnPP/240 mg FeS), or placebo within 24-48 h before surgery. The primary outcome was a preoperative preconditioning response, measured by a composite of plasma HO-1, IL-10, and ferritin. Safety was assessed by adverse events and laboratory parameters. Prespecified adaptive criteria permitted early stopping and enrichment. This trial is registered with ClinicalTrials.gov, NCT04564833.

Findings

Between Aug 4, 2021, and Nov 9, 2022, of 135 patients who were enrolled and randomly allocated to a study group (46 high-dose, 45 low-dose, 44 placebo), 132 (98%) were included in the primary analysis (46 high-dose, 42 low-dose, 44 placebo). At interim, the trial proceeded to full enrollment without enrichment. RBT-1 led to a greater preconditioning response than did placebo at high-dose (geometric least squares mean [GLSM] ratio, 3.58; 95% CI, 2.91-4.41; p < 0.0001) and low-dose (GLSM ratio, 2.62; 95% CI, 2.11-3.24; p < 0.0001). RBT-1 was generally well tolerated by patients. The primary drug-related adverse event was dose-dependent photosensitivity, observed in 12 (26%) of 46 patients treated with high-dose RBT-1 and in six (13%) of 45 patients treated with low-dose RBT-1 (safety population).

Interpretation

RBT-1 demonstrated a statistically significant cytoprotective preconditioning response and a manageable safety profile. Further research is needed. A phase 3 trial is planned.

Funding

Renibus Therapeutics, Inc.

A Contemporary Review of the Use of Extracorporeal CytoSorb® Hemoadsorption Therapy in Patients with Infective Endocarditis

Infective endocarditis (IE) is a rare but severe disease with high morbidity and mortality. Cardiac surgery plays a major role in the contemporary clinical management of IE patients. During cardiac surgery, cardiopulmonary bypass significantly contributes to an increased risk of organ dysfunction and mortality by inducing an acute inflammatory response, vascular endothelial cell injury, impairment of the coagulation cascade, and ischemia-reperfusion injury. During the past decade, the use of extracorporeal hemoadsorption therapy with the CytoSorb® hemoadsorber (CytoSorbents Europe GmbH, Berlin, Germany) has been proposed as an adjuvant therapy to mediate inflammatory responses in IE patients undergoing cardiac surgery with cardiopulmonary bypass. However, there is currently no systematic evaluation of the effect of CytoSorb® hemoadsorption on clinical outcomes such as hemodynamics, organ dysfunction, and mortality in patients with IE. Therefore, in this review, we exclusively discuss contemporary findings concerning the rationale, clinical evidence, and future perspectives for CytoSorb® hemoadsorption therapy in IE patients.

Cardiac Radiofrequency Ablation Exacerbates Myocardial Injury through Pro-Inflammatory Response and Pro-Oxidative Stress in Elderly Patients with Persistent Atrial Fibrillation

BACKGROUND

There is a need to assess myocardial damage after radiofrequency ablation of the pulmonary veins (PV) for persistent atrial fibrillation (PAF) in elderly patients.

OBJECTIVE

To evaluate oxidative stress, inflammatory response and myocardial damage in elderly patients with PAF after radiofrequency ablation of the PV.

METHODS

High-sensitivity troponin T (hsTnT), malondialdehyde-modified low-density lipoprotein (MDA-LDL), acrolein (ACR), lipid hydroperoxide (LHP), toll-like receptor 4 (TLR4), soluble growth stimulation expressed gene 2 (sST2), angiotensin II (Ang II) and myocardial blood flow (MBF) were determined before ablation and at 1, 3 and 5 months after radiofrequency ablation.

RESULTS

The levels of hsTnT, MDA-LDL, ACR, LHP, TLR4, sST2 and Ang II were increased 3 months after ablations compared with before ablation and 1 month after ablation, respectively (P<0.001); they were further increased at 5 months after ablation compared with the 1- and 3-month groups, respectively (P<0.001). MBF was decreased in the 3 months group after ablations compared with before ablation and 1-month after ablation, respectively (P<0.001), and was further decreased in 5-months after ablations compared with 1-month and 3-month groups, respectively (P<0.001). Patients with epicardial monopolar radiofrequency ablation had higher levels of hsTnT, MDA-LDL, ACR, LHP, TLR4, sST2, Ang II and lower MBF than patients with endocardial monopolar and bipolar radiofrequency ablations, respectively (P<0.001).

CONCLUSION

Monopolar radiofrequency ablation method could result in more myocardial injury than bipolar radiofrequency ablation. Oxidative stress and inflammatory response may be involved in cardiac radiofrequency ablation-induced myocardial injury, resulting in myocardial ischemia in elderly patients with PAF.

Epigenetic MicroRNAs as Prognostic Markers of Postoperative Atrial Fibrillation: A Systematic Review

Postoperative atrial fibrillation (POAF) is a common complication after cardiac surgery, increasing the risk for adverse outcomes such as perioperative and long-term mortality, stroke, myocardial infarction, and other thromboembolic events. Epigenetic biomarkers show promise as prognostic tools for POAF. Epigenetic changes, such as DNA methylation, histone modification, and microRNAs (miRNA), can result in altered gene expression and the development of various pathological conditions. This systematic review aims to present the current literature on the association between various epigenetic markers and the development of POAF following cardiac surgery. Here, an electronic literature search was performed using MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, and Google Scholar to identify studies that reported the role of epigenetic markers in the development of POAF. Five of the 6 studies focused on miRNAs and their association with POAF. In POAF patients, the expression of miR-1 and miR-483-5p were upregulated in the right atrial appendage (RAA), while the levels of miR-133A, miR-208a, miR-23a, miR-26a, miR-29a, miR-29b, and miR-29c were decreased in the RAA and venous blood. One study examined cytosines followed by guanines (CpGs) as DNA methylation markers. Across all studies, 488 human subjects who had undergone cardiac surgery were investigated, and 195 subjects (39.9%) developed new-onset POAF. The current literature suggests that miRNAs may play a role in predicting the development of atrial fibrillation after cardiac surgery. However, more robust clinical data are required to justify their role in routine clinical practice.

Developing Pharmacological Therapies for Atrial Fibrillation Targeting Mitochondrial Dysfunction and Oxidative Stress: A Scoping Review

Atrial fibrillation (AF) is a cardiac arrhythmia caused by electrophysiological anomalies in the atrial tissue, tissue degradation, structural abnormalities, and comorbidities. A direct relationship exists between AF and altered mitochondrial activity resulting from membrane potential loss, contractile dysfunction, or decreased ATP levels. This review aimed to elucidate the role of mitochondrial oxidative mechanisms in AF pathophysiology, the impact of mitochondrial oxidative stress on AF initiation and perpetuation, and current therapies. This review followed the Preferred Reporting Items for Systematic Reviews and the Meta-Analysis Extension for Scoping Reviews. PubMed, Excerpta Medica Database, and Scopus were explored until June 2023 using "MESH terms". Bibliographic references to relevant papers were also included. Oxidative stress is an imbalance that causes cellular damage from excessive oxidation, resulting in conditions such as AF. An imbalance in reactive oxygen species production and elimination can cause mitochondrial damage, cellular apoptosis, and cardiovascular diseases. Oxidative stress and inflammation are intrinsically linked, and inflammatory pathways are highly correlated with the occurrence of AF. AF is an intricate cardiac condition that requires innovative therapeutic approaches. The involvement of mitochondrial oxidative stress in the pathophysiology of AF introduces novel strategies for clinical treatment.

Detection and modification of biomarkers of inflammation determining successful rhythm control in patients with atrial fibrillation

INTRODUCTION

Multiple pathophysiological mechanisms are involved in the pathogenesis of atrial fibrillation (AF). Growing evidence suggests that both local and systemic inflammation plays a key role even in early stages and its progression towards persisting and permanent AF. Rhythm control therapy via pulmonary vein isolation or cardioversion is the cornerstone of AF therapy for most symptomatic patients, yet arrhythmia recurrence after treatment is still common, especially in patients with persistent AF.

MATERIAL AND METHODS

In this review, we summarize the current state of knowledge of biomarkers of inflammation with prognostic value in patients with atrial fibrillation as well as anti-inflammatory medication with potential benefits after rhythm control therapy.

RESULTS AND DISCUSSION

Both onset of AF, progression and arrhythmia recurrence after rhythm control therapy can be caused by local and systemic inflammation. Various inflammatory biomarkers have been established to predict treatment success. Furthermore, additional anti-inflammatory therapy may significantly improve success rates.

Associations of Inflammatory Biomarkers With the Risk of Morbidity and Mortality After Cardiac Surgery: A Systematic Review and Meta-analysis

BACKGROUND

Although inflammatory biomarkers have been associated with cardiovascular events in nonsurgical settings, these associations have not been systematically addressed in patients undergoing cardiac surgery. This review aimed to evaluate the relationships of inflammatory markers with mortality and adverse cardiovascular events in patients undergoing cardiac surgery.

METHODS

Medline, Embase, and Central databases were systematically searched for studies reporting pre- or postoperative levels of inflammatory biomarkers in patients undergoing cardiac surgery. Outcomes of interest were postoperative mortality, nonfatal myocardial infarction, stroke, congestive heart failure, and major adverse cardiovascular events (MACE). Studies reporting multivariable adjusted risk estimates were included. Risk estimates were pooled with the use of random-effects models and reported as summary odds ratios (ORs).

RESULTS

Among 14,465 citations identified, 29 studies including 29,401 participants met the eligibility criteria. The average follow-up time after surgery was 31 months. Preoperative C-reactive protein (CRP) levels were associated with an increased risk of all-cause mortality (OR 1.88, 95% CI 1.60-2.20; I2 = 19%; 11 studies) and MACE (OR 1.73, 95% CI 1.34-2.24; I2 = 0%; 3 studies). CRP levels measured on postoperative day 6 (OR 7.4, 95% CI 2.90-18.88, 1 study) and day 10 (OR 11.8, 95% CI 3.50-39.78, 1 study) were associated with a higher risk of all-cause mortality. Less, but overall similar, information was available for other inflammatory biomarkers.

CONCLUSIONS

In this large meta-analysis, inflammatory biomarkers measured before or after cardiac surgery were associated with mortality and adverse cardiovascular outcomes in patients undergoing cardiac surgery.

Biochemical Changes in Cardiopulmonary Bypass in Cardiac Surgery: New Insights

Patients undergoing coronary revascularization with extracorporeal circulation or cardiopulmonary bypass (CPB) may develop several biochemical changes in the microcirculation that lead to a systemic inflammatory response. Surgical incision, post-CPB reperfusion injury and blood contact with non-endothelial membranes can activate inflammatory signaling pathways that lead to the production and activation of inflammatory cells, with cytokine production and oxidative stress. This inflammatory storm can cause damage to vital organs, especially the heart, and thus lead to complications in the postoperative period. In addition to the organic pathophysiology during and after the period of exposure to extracorporeal circulation, this review addresses new perspectives for intraoperative treatment and management that may lead to a reduction in this inflammatory storm and thereby improve the prognosis and possibly reduce the mortality of these patients.

Role of magnesium alone or in combination with diltiazem and/or amiodarone in prevention of atrial fibrillation following off-pump coronary artery bypass grafting

Objectives

In this study the authors have tried to examine the role of magnesium alone or in combination with diltiazem and / or amiodarone in prevention of atrial fibrillation (AF) following off-pump coronary artery bypass grafting (CABG).

Background

AF after CABG is common and contributes to morbidity and mortality. Various pharmacological preventive measures including magnesium, amiodarone, diltiazem, and combination therapy among others have been tried to lower the incidence of AF. Most of the studies have been performed in patients undergoing conventional on-pump CABG. In this uncontrolled trial, efficacy of magnesium alone or in combination with amiodarone and / or diltiazem has been studied in patients undergoing off-pump CABG.

Methods

One hundred and fifty patients undergoing off-pump CABG were divided into 3 groups, Group M (n=21) received intraoperative magnesium infusion at 30mg/ kg over 1 hour after midline sternotomy; Group MD (n=78) received magnesium infusion in similar manner with diltiazem infusion at 0.05 μg/kg/hr throughout the intraoperative period; Group AMD (n=51) received preoperative oral amiodarone at a dose of 200 mg three times a day for 3 days followed by 200 mg twice daily for another 3 days followed by 200 mg once daily till the day of surgery along with magnesium and diltiazem infusion as in other groups. AF lasting more than 10 min or requiring medical intervention was considered as AF.

Results

The overall incidence of postoperative AF was 12.6% with 11.7% in group AMD, 19% in group M, and 11.5% in group MD, which was not statistically significant.

Conclusions

It is concluded that the use of amiodarone and/or diltiazem in addition to magnesium did not result in additional benefit of lowering the incidence of AF.

Plasma Exosome Hemoglobin Released During Surgery Is Associated With Cardiac Injury in Animal Model

BACKGROUND

Patients with valvular heart disease require cardiopulmonary bypass and cardiac arrest. Here, we test the hypothesis that exosomal hemoglobin formed during cardiopulmonary bypass mediates acute cardiac injury in humans and in an animal model system.

METHODS

Plasma exosomes were collected from arterial blood at baseline and 30 minutes after aortic cross-clamp release in 20 patients with primary mitral regurgitation and 7 with aortic stenosis. These exosomes were injected into Sprague-Dawley rats and studied at multiple times up to 30 days. Tissue was examined by hematoxylin and eosin stain, immunohistochemistry, transmission electron microscopy, and brain natriuretic peptide.

RESULTS

Troponin I levels increased from 36 ± 88 ng/L to 3622 ± 3054 ng/L and correlated with exosome hemoglobin content (Spearman r = 0.7136, < .0001, n = 24). Injection of exosomes isolated 30 minutes after cross-clamp release into Sprague-Dawley rats resulted in cardiomyocyte myofibrillar loss at 3 days. Transmission electron microscopy demonstrated accumulation of electron dense particles of ferritin within cardiomyocytes, in the interstitial space, and within exosomes. At 21 days after injection, there was myofibrillar and myosin breakdown, interstitial fibrosis, elevated brain natriuretic peptide, and left ventricle diastolic dysfunction measured by echocardiography/Doppler. Pericardial fluid exosomal hemoglobin content is fourfold higher than simultaneous plasma exosome hemoglobin, suggesting a cardiac source of exosomal hemoglobin.

CONCLUSIONS

Red blood cell and cardiac-derived exosomal hemoglobin may be involved in myocardial injury during cardiopulmonary bypass in patients with valvular heart disease.

Relationship between platelet mass index and postoperative atrial fibrillation after elective coronary artery bypass surgery: a retrospective study

BACKGROUND

Atrial fibrillation (AF) is the most common complication after cardiac surgery. The pathogenesis of postoperative atrial fibrillation (POAF) is multifactorial and one of the known factors is inflammation. Platelet mass index (PMI) is an indicator of platelet activation and a better inflammatory marker than mean platelet volume (MPV). In this retrospective study, we investigated the relationship between POAF and PMI.

METHODS

The study included 848 consecutive patients (655 male and 193 female) who had elective isolated coronary artery by-pass grafting (CABG) or combined CABG and valvular surgery. Platelet count and MPV were measured from preoperative blood samples to calculate PMI. Post-operative atrial fibrillation was defined as irregular and fibrillatory P waves occurring 48-96 h after cardiac surgery and lasting at least 30 s. The PMI values in patients who developed POAF were compared with those in patients who did not develop POAF.

RESULTS

Patients who developed POAF had higher PMI values (2549.3 ± 1077.1) when compared with patients in sinus rhythm (2248.1 ± 683.4; p < 0.01). In multivariate regression analysis, age (OR: 1.05; 95% CI: 1.02-1.09; p = 0.01), left atrial diameter (OR: 1.05; 95% CI: 1.03-1.09; p = 0.02), hs-CRP (OR: 1.09; 95%CI: 1.05-1.13; p < 0.01), EuroSCORE II (OR: 1.27; 95% CI: 1.14-1.41; p < 0.01), and PMI (OR: 1.01; 95% CI: 1.001-1.02; p < 0.01) were independent predictors of POAF. In ROC analysis, PMI ≥ 2286 predicted POAF development with a sensitivity of 69% and a specificity of 58% (AUC: 0.66; p < 0.01) CONCLUSION: A significant relationship was found between preoperatively calculated PMI and POAF. We showed that PMI may be used to predict patients who are at high risk of developing POAF.

The dose-response relationships of the direct scavenging activity of amide-based local anesthetics against multiple free radicals

This study aimed to illustrate the dose-response relationships of the direct scavenging activity of amide-based local anesthetics against multiple free radicals in vitro. We have demonstrated that amide-type local anesthetics selectively and directly scavenge some free radicals. Three kinds of free radicals were eliminated by all the four local anesthetics examined. Mepivacaine, lidocaine, bupivacaine, and dibucaine scavenged hydroxyl radicals in dose-dependent manners. Ascorbyl free radicals were also scavenged in dose-dependent manners, and lastly singlet oxygen was scavenged in dose-dependent manners. Three other free radicals were not scavenged by all of the four local anesthetics; tert-butoxyl radical was scavenged by all the anesthetics examined but dibucaine, nitric oxide by mepivacaine but not by the other three, and tyrosyl radical by mepivacaine and lidocaine but not by the other two. Some free radicals (superoxide anion, tert-butyl peroxyl radical, DPPH) were not scavenged by any of the four local anesthetics. The local anesthetics were also shown to inhibit lipid peroxidation by TBARS assay. These results suggest that local anesthetics have antioxidant properties through their free radical scavenging activities.

CABG Patients Develop Global DNA Hypermethylation, That Negatively Affect the Mitochondrial Function and Promote Post-Surgical Cognitive Decline: A Proof of Concept in Small Cohort

Global DNA hypermethylation and mitochondrial dysfunction are reported to be associated with the development of mild cognitive decline (MCI). The present study aims to generate preliminary data that connect the above association with post-surgical coronary artery bypass grafting (CABG) cognitive decline in patients. Data were collected from 70 CABG patients and 25 age-matched controls. Cognitive function was assessed using the Montreal Cognitive Assessment (MOCA) test on day 1 (before surgery) and on the day of discharge. Similarly, blood was collected before and one day after the CABG procedure for mitochondrial functional analysis and expression of DNA methylation genes. Test analysis score suggested 31 (44%) patients had MCI before discharge. These patients showed a significant decrease in complex I activity and an increase in malondialdehyde levels (p < 0.001) from the control blood samples. Post-surgical samples showed a significant reduction in blood MT-ND1 mRNA expression from control and from pre-surgical samples (p < 0.005), along with elevated DNMT1 gene expression (p < 0.047), with an insignificant increase in TET1 and TET3 gene expression. Correlation analysis showed a significant positive relation between cognitive decline and elevated blood DNMT1 and declined blood complex I activity, signifying that cognitive decline experienced by post-surgical CABG patients is associated with increased DNMT1 expression and declined complex I activity. Based on the data, we conclude that both DNA hypermethylation and mitochondrial dysfunction are associated with post-CABG MCI, where the former is negatively correlated, and the latter is positively correlated with post-surgical MCI in CABG cases. Additionally, a multimarker approach that comprises MOCA, DNA methylation, DNMT, and NQR activities can be utilized to stratify the population that is sensitive to developing post-CABG MCI.

Prediction of post-operative atrial fibrillation in patients after cardiac surgery using heart rate variability

PURPOSE

Post-operative atrial fibrillation (PoAF) occurs in ~ 30% of patients after cardiac surgery. The etiology of PoAF is complex, but a disbalance in autonomic systems plays an important role. The goal of this study was to assess whether pre-operative heart rate variability analysis can predict the risk of PoAF.

METHODS

Patients without a history of AF with an indication for cardiac surgery were included. Two-hour ECG recordings one day before surgery was used for the HRV analysis. Univariate and multivariate logistic regression, including all HRV parameters, their combination, and clinical variables, were calculated to find the best predictive model for post-operative AF.

RESULTS

One hundred and thirty-seven patients (33 women) were enrolled in the study. PoAF occurred in 48 patients (35%, AF group); the remaining 89 patients were in the NoAF group. AF patients were significantly older (69.1 ± 8.6 vs. 63.4 ± 10.5 yrs., p = 0.002), and had higher CHA₂DS₂-VASc score (3 ± 1.4 vs. 2.5 ± 1.3, p = 0.01). In the multivariate regression model, parameters independently associated with higher risk of AF were pNN50, TINN, absolute power VLF, LF and HF, total power, SD2, and the Porta index. A combination of clinical variables with HRV parameters in the ROC analysis achieved an AUC of 0.86, a sensitivity of 0.95, and a specificity of 0.57 and was more effective in PoAF prediction than a combination of clinical variables alone.

CONCLUSION

A combination of several HRV parameters is helpful in predicting the risk of PoAF. Attenuation of heart rate variability increases the risk for PoAF.

Prediction of postoperative atrial fibrillation with the systemic immune-inflammation index in patients undergoing cardiac surgery using cardiopulmonary bypass: a retrospective, single-center study

The systemic immune-inflammation index (SII, platelet count × neutrophil-lymphocyte ratio) is a novel parameter for systemic inflammation. Cardiopulmonary bypass (CPB) is associated with systemic inflammatory responses. This retrospective study aimed to determine whether SII could predict postoperative atrial fibrillation (POAF) after cardiac surgery using CPB. Patients who underwent cardiac surgery using CPB between January 2020 and July 2021 were included. The primary outcome was POAF incidence within 7 days. Receiver-operating characteristic (ROC) curve analysis was used to evaluate SII ability in predicting POAF. Multivariable analysis was used to estimate the independent association between SII and POAF development. The study included 212 patients, and 90 (43%) developed POAF. The preoperative SII cutoff of 545 × 109/L predicted a poor outcome with 71% sensitivity and 81% specificity. The area under the ROC curve was 0.80 (95% confidence interval [CI] 0.73-0.86). Multivariable analysis showed that SII ≥ 545 × 109/L was associated with the development of POAF (odds ratio 10.2; 95% CI 5.1-20.2, P < 0.001). SII predicted POAF with a curve of 0.91 (95% CI 0.82-1.00) in patients with coronary artery bypass grafting (CABG); the corresponding value in patients without CABG was 0.75 (95% CI 0.67-0.83). Preoperative SII may be a useful prognostic biomarker for POAF in patients undergoing cardiac surgery using CPB. Moreover, preoperative SII may play an important role in predicting POAF in patients undergoing CABG.

Year in Review 2022: Noteworthy Literature in Cardiac Anesthesiology

Last year researchers made substantial progress in work relevant to the practice of cardiac anesthesiology. We reviewed 389 articles published in 2022 focused on topics related to clinical practice to identify 16 that will impact the current and future practice of cardiac anesthesiology. We identified 4 broad themes including risk prediction, postoperative outcomes, clinical practice, and technological advances. These articles are representative of the best work in our field in 2022.

Patterns of cytokine release and association with new onset of post-cardiac surgery atrial fibrillation

Introduction

Postoperative Atrial Fibrillation (POAF) is a common complication of cardiac surgery, associated with increased mortality, stroke risk, cardiac failure and prolonged hospital stay. Our study aimed to assess the patterns of release of systemic cytokines in patients with and without POAF.

Methods

A post-hoc analysis of the Remote Ischemic Preconditioning (RIPC) trial, including 121 patients (93 males and 28 females, mean age of 68 years old) who underwent isolated coronary artery bypass grafting (CABG) and aortic valve replacement (AVR). Mixed-effect models were used to analyze patterns of release of cytokines in POAF and non-AF patients. A logistic regression model was used to assess the effect of peak cytokine concentration (6 h after the aortic cross-clamp release) alongside other clinical predictors on the development of POAF.

Results

We found no significant difference in the patterns of release of IL-6 (p = 0.52), IL-10 (p = 0.39), IL-8 (p = 0.20) and TNF-α (p = 0.55) between POAF and non-AF patients. Also, we found no significant predictive value in peak concentrations of IL-6 (p = 0.2), IL-8 (p = >0.9), IL-10 (p = >0.9) and Tumour Necrosis Factor Alpha (TNF-α)(p = 0.6), however age and aortic cross-clamp time were significant predictors of POAF development across all models.

Conclusions

Our study suggests no significant association exists between cytokine release patterns and the development of POAF. Age and Aortic Cross-clamp time were found to be significant predictors of POAF.

Mechanisms of Atrial Fibrillation: How Our Knowledge Affects Clinical Practice

Atrial fibrillation (AF) is a very common arrhythmia that mainly affects older individuals. The mechanism of atrial fibrillation is complex and is related to the pathogenesis of trigger activation and the perpetuation of arrhythmia. The pulmonary veins in the left atrium arei confirm that onfirm the most common triggers due to their distinct anatomical and electrophysiological properties. As a result, their electrical isolation by ablation is the cornerstone of invasive AF treatment. Multiple factors and comorbidities affect the atrial tissue and lead to myocardial stretch. Several neurohormonal and structural changes occur, leading to inflammation and oxidative stress and, consequently, a fibrotic substrate created by myofibroblasts, which encourages AF perpetuation. Several mechanisms are implemented into daily clinical practice in both interventions in and the medical treatment of atrial fibrillation.

Clinical Profiling and Biomarkers for Post-Operative Atrial Fibrillation Prediction in Patients Undergoing Cardiac Surgery

Post-operative atrial fibrillation (POAF) is the most common arrhythmia in the post-operative period after cardiac surgery. We aim to investigate the main clinical, local, and/or peripheral biochemical and molecular predictors for POAF in patients undergoing coronary and/or valve surgery. Between August 2020 and September 2022, consecutive patients undergoing cardiac surgery without previous history of AF were studied. Clinical variables, plasma, and biological tissues (epicardial and subcutaneous fat) were obtained before surgery. Pre-operative markers associated with inflammation, adiposity, atrial stretch, and fibrosis were analyzed on peripheral and local samples with multiplex assay and real-time PCR. Univariate and multivariate logistic regression analyses were performed in order to identify the main predictors for POAF. Patients were followed-up until hospital discharge. Out of 123 consecutive patients without prior AF, 43 (34.9%) developed POAF during hospitalization. The main predictors were cardiopulmonary bypass time (odds ratio (OR) 1.008 (95% confidence interval (CI), 1.002-1.013), p = 0.005), and plasma pre-operative orosomucoid levels (OR 1.008 (1.206-5.761). After studying differences regarding sex, orosomucoid was the best predictor for POAF in women (OR 2.639 (95% CI, 1.455-4.788), p = 0.027) but not in men. The results support the pre-operative inflammation pathway as a factor involved in the risk of POAF, mainly in women.

Characteristics of preoperative atrial fibrillation in geriatric patients with hip fracture and construction of a clinical prediction model: a retrospective cohort study

INTRODUCTION

Atrial fibrillation is the most common atrial arrhythmia in the perioperative period and is associated with prolonged hospital stay, increased costs, and increased mortality. However, there are few data on the predictors and incidence of preoperative atrial fibrillation in hip fracture patients. Our aim was to identify predictors of preoperative atrial fibrillation and to propose a valid clinical prediction model.

METHODS

Predictor variables included demographic and clinical variables. LASSO regression analyzes were performed to identify predictors of preoperative atrial fibrillation, and models were constructed and presented as nomograms. Area under the curve, calibration curve, and decision curve analysis (DCA) were used to examine the discriminative power, calibration, and clinical efficacy of the predictive models. Bootstrapping was used for validation.

RESULTS

A total of 1415 elderly patients with hip fractures were analyzed. Overall, 7.1% of patients had preoperative atrial fibrillation, and they were at significant risk for thromboembolic events. Patients with preoperative AF had a significantly longer delay in surgery than those without preoperative atrial fibrillation (p < 0.05). Predictors for preoperative atrial fibrillation were hypertension (OR 1.784, 95% CI 1.136-2.802, p < 0.05), C-reactive protein at admission (OR 1.329, 95% CI 1.048-1.662, p < 0.05), systemic inflammatory response index at admission (OR 2.137, 95% CI, 1.678-2.721 p < 0.05), Age-Adjusted Charlson Comorbidity Index (OR 1.542, 95% CI 1.326-1.794, p < 0.05), low potassium(OR 2.538, 95% CI 1.623-3.968, p < 0.05), anemia(OR 1.542, 95% CI 1.326-1.794, p < 0.05). Good discrimination and calibration effect of the model was showed. Interval validation could still achieve the C-index value of 0.799. DCA demonstrated this nomogram has good clinical utility.

CONCLUSION

This model has a good predictive effect on preoperative atrial fibrillation in elderly patients with hip fractures, which can help to better plan clinical evaluation.

Postoperative glucocorticoids in patients with acute type A aortic dissection (GLAD): study protocol for a prospective, single-center, randomized controlled trial

BACKGROUND

Patients receiving surgical treatment of acute type A Aortic Dissection (aTAAD) are common to suffer organ dysfunction in the intensive care unit due to overwhelming inflammation. Previous studies have revealed that glucocorticoids may reduce complications in certain patient groups, but evidence between postoperative glucocorticoids administration and improvement in organ dysfunction after aTAAD surgery are lacking.

METHODS

This study will be an investigator-initiated, prospective, single-blind, randomized, single-center study. Subjects with confirmed diagnosis of aTAAD undergoing surgical treatment will be enrolled and 1:1 randomly assigned to receive either glucocorticoids or normal treatment. All patients in the glucocorticoids group will be given methylprednisolone intravenously for 3 days after enrollment. The primary endpoint will be the amplitude of variation of Sequential Organ Failure Assessment score on post-operative day 4 compared to baseline.

DISCUSSION

The trial will explore the rationale for postoperative application of glucocorticoids in patients after aTAAD surgery.

TRIAL REGISTRATION

This study has been registered on ClinicalTrials.gov (NCT04734418).

Effect of Perioperative Oral Vitamin C Supplementation on In-Hospital Postoperative Medication Costs for Cardiac Surgery Patients: A Prospective, Single-Centre, Randomised Clinical Trial

BACKGROUND

Due to its antioxidant properties, vitamin C might be a promising and effective strategy for preventing postoperative atrial fibrillation (POAF) after cardiac surgery. This study was aimed at evaluating whether vitamin C supplementation is effective in reducing the cost of in-hospital postoperative medication used for patients undergoing coronary artery bypass (CABG) or valve surgery (±CABG).

OBJECTIVE

The primary goal of this study was to evaluate the impact of perioperative vitamin C supplementation in patients undergoing cardiac surgery on in-hospital postoperative medication costs, while secondary endpoints were the effects on length of stay (LOS) in both the intensive care unit (ICU) and the hospital, and the incidence of POAF.

MATERIAL AND METHODS

From November 2018 to January 2021, 253 patients planned for CABG or valve surgery (±CABG) in AZ Maria Middelares, Ghent, Belgium, and who met the inclusion criteria (≥18 years of age, all having cardiac sinus rhythm, and who provided written informed consent) were randomised into a placebo group or vitamin C group. The medication was administered orally (1 g twice daily), starting from 5 days preoperatively until 10 days postoperatively. The medication used, LOS in the hospital/ICU, and development of clinically relevant POAF in the ICU were registered.

RESULTS

Mean medication costs were €264.6 ± 98.1 for patients in the vitamin C group and €294.9 ± 267.3 for patients in the placebo group. When stratifying according to the type of surgery (CABG or valve surgery [±CABG]), these costs did not significantly differ. There was no significant difference in LOS or the incidence of clinically relevant POAF.

CONCLUSION

Our data did not identify any short-term financial impact on postoperative medication costs after oral perioperative vitamin C supplementation (1 g twice daily) for patients undergoing a CABG procedure or valve surgery (±CABG). No effect was found on the LOS or the incidence of clinically relevant POAF. Potential effects in the longer term, after intravenous administration of vitamin C or in other types of (cardiac) surgery, are still to be investigated.

CLINICAL TRIALS REGISTRATION NUMBER

NCT03592680.

The Prognostic Significance of Red Cell Distribution Width in Cardiac Surgery: A Systematic Review and Meta-Analysis

RED CELL DISTRIBUTION WIDTH (RDW) is a routinely available biomarker of likely erythropoietic dysfunction, which may be associated with adverse outcomes after cardiac surgery. This systematic review and meta-analysis aimed to clarify the prognostic value of RDW in patients undergoing cardiac surgery. The authors searched MEDLINE, Embase, and the Cochrane Library from inception to May 10, 2022 for studies investigating the association between elevated RDW (as defined by the authors of included studies) and adverse outcomes after cardiac surgery. Herein, the authors extracted maximally adjusted hazard ratios (HRs) and odds ratios (ORs) with associated CIs, and pooled them using random-effects inverse- variance modeling. The authors explored interstudy heterogeneity using metaregression. The authors included 26 studies involving 48,092 patients who had undergone cardiac surgery. Elevated preoperative RDW was associated with long-term mortality (pooled HR 1.63, 95% CI 1.05-2.52), short-term mortality (pooled OR 2.16, 95% CI 1.21-3.87), acute kidney injury (AKI; pooled OR 1.30, 95% CI 1.19-1.41) and postoperative atrial fibrillation (POAF; pooled OR 1.44, 95% CI 1.05-1.96). Some studies suggested a significant association between preoperative RDW elevation and neurologic complications; however, their number was insufficient for meta-analysis. The postoperative RDW levels were less consistently reported and could not be meta-analyzed. In conclusion, the authors found that elevated preoperative RDW was associated with increased short- and long-term mortality, POAF, and AKI after cardiac surgery. Further research is needed to investigate its role in the risk stratification of patients undergoing cardiac surgery.

Prognostic implications of Global Leadership Initiative on Malnutrition-defined malnutrition in older patients who underwent cardiac surgery in China

BACKGROUND

The proportion of older patients who are candidates for cardiac surgery is increasing. Growing evidence has shown that malnutrition is associated with a poor prognosis after cardiac surgery. The present study aimed to investigate the prognostic implications of malnutrition defined by the Global Leadership Initiative on Malnutrition in older patients who underwent cardiac surgery.

METHODS

From November 2015 to January 2021, 401 older patients who underwent cardiac surgery were retrospectively enrolled and evaluated using the Global Leadership Initiative on Malnutrition criteria. The perioperative characteristics and clinical outcomes were collected. The independent risk factors for postoperative complications and overall survival were analyzed.

RESULTS

The prevalence of Global Leadership Initiative on Malnutrition-defined malnutrition was 22.7% in this study. Patients with Global Leadership Initiative on Malnutrition-defined malnutrition had higher risks of postoperative complications (65.9% vs 49.7%, P = .006) and poor overall survival (68.1% vs 83.9%, P = .0019). Global Leadership Initiative on Malnutrition-defined malnutrition was also related to a longer postoperative hospital stay and prolonged intensive care stay. Five factors were identified as independent risk factors for overall survival: Global Leadership Initiative on Malnutrition-defined malnutrition (P = .009), chronic heart failure (P = .007), atrial fibrillation (P = .029), operative time (P < .001) and hemoglobin (P = .044).

CONCLUSION

We demonstrated the prognostic implications of Global Leadership Initiative on Malnutrition-defined malnutrition in older patients who underwent cardiac surgery for the first time. This study highlights the necessity of using the Global Leadership Initiative on Malnutrition assessment in the comprehensive preoperative risk assessment of cardiac surgery.