Plasma Catecholamine Levels on the Morning of Surgery Predict Post-Operative Atrial Fibrillation

The Use of the Perfusion Index to Predict Post-Induction Hypotension in Patients Undergoing General Anesthesia: A Systematic Review and Meta-Analysis

Post-induction hypotension (PIH) is a common and potentially serious complication of general anesthesia. This meta-analysis (Prospero registration number: CRD42024566321) aimed to evaluate the predictive efficacy of the perfusion index (PI) for PIH in patients undergoing general anesthesia. A comprehensive literature search was performed using multiple electronic databases (Google Scholar, EMBASE, Cochrane Library, and MEDLINE). Studies involving adult patients undergoing general anesthesia, with the PI measured before anesthesia induction and reporting PIH incidence, were included. The primary outcome was the diagnostic accuracy of the PI in predicting the probability of PIH. The secondary outcome was the pooled PIH incidence. Eight studies with 678 patients were included. The pooled incidence of PIH was 44.8% (95% confidence interval [CI]: 29.9%-60.8%). The combined sensitivity and specificity of the PI for predicting PIH were 0.84 (95% CI: 0.65-0.94) and 0.82 (95% CI: 0.70-0.90), respectively. The summary receiver operating characteristic (sROC) analysis revealed an area under curve of 0.89 (95% CI: 0.86-0.92). The Deek's funnel plot asymmetry test indicated no significant publication bias. The PI demonstrates high predictive efficacy for PIH in patients undergoing general anesthesia, indicating that it can be a valuable tool for identifying those at risk of PIH.

Atrial fibrillation and survival on a medical intensive care unit

BACKGROUND

Atrial fibrillation (AF) is common among patients in the intensive care unit (ICU) and can be triggered by severe illness or preexisting conditions. It is debated if AF is an independent predictor of poor outcome.

METHODS

Data derives from a single center retrospective registry including all patients with a stay on the medical ICU for >24 h. The primary endpoint was ICU survival. Secondary endpoints included receiving mechanical support (renal, respiratory or circulatory), hemodynamic parameters during AF, rate and rhythm control strategies, anticoagulation, and documentation.

RESULTS

A total of 616 patients (male gender 62.3%, median age 75 years) were included in our analysis. New-onset AF was diagnosed in 87 patients (14.1%), 136 (22.1%) presented with preexisting AF, and 393 (63.8%) did not develop AF. Initial episodes of new-onset AF exhibited higher hemodynamic instability than episodes in preexisting cases, with elevated heart rates and increased catecholamine doses (both p < 0.001). ICU survival in new-onset AF was 80.5% (70/87) compared to 92.4% (363/393) in patients without AF (OR 0.340, CI 0.182-0.658, p < 0.001). Likewise, ICU survival in preexisting AF was 86.8% (118/136) was significantly lower compared to no AF (OR 0.542, CI 0.290-0.986, p = 0.050*). Independent predictors of ICU survival for patients were atrial fibrillation (p = 0.016), resuscitation before or during ICU stay (p < 0.001), and receiving acute dialysis on ICU (p = 0.002).

CONCLUSIONS

ICU survival is noticeably lower in patients with new-onset or preexisting atrial fibrillation compared to those without. Patients who develop new-onset AF during their ICU stay warrant special attention for both short-term and long-term care strategies.

Biochemical Predictors of New-Onset Atrial Fibrillation after Ascending Aorta Replacement Surgery in Acute Type A Aortic Dissection Patients

Objective. This study aimed to determine the risk factors of new-onset postoperative atrial fibrillation after ascending aortic replacement in acute type A aortic dissection patients, with emphasis on biochemical parameters. Methods. From Jan 2020 to Dec 2021, a total of 435 acute type A aortic dissection patients who underwent ascending aortic replacement and without a history of atrial fibrillation were retrospectively analyzed in this study. Perioperative data of these patients were obtained from the hospital’s database. The 30-day follow-up was via telephone interviews. The multivariate regression analysis was used to identify risk factors that may be predictive of postoperative atrial fibrillation. Results. 218 (50.1%) patients experienced postoperative atrial fibrillation after ascending aorta replacement surgery. Older age (OR = 1.081 (1.059–1.104), $p<0.001$ ), higher total bile acid (OR = 1.064 (1.024–1.106), $p$  = 0.002), glucose (OR = 1.180 (1.038–1.342), $p$  = 0.012), and serum potassium (OR = 2.313 (1.078–4.960), $p$  = 0.031) were identified by multivariate regression analysis as risk factors of postoperative atrial fibrillation. The multivariate regression analysis prediction model incorporating these four factors had a good prediction effect (AUC = 0.769 (0.723–0.816), $p<0.001$ ). Conclusions. Older age, higher total bile acid, glucose, and serum potassium were risk factors of postoperative atrial fibrillation after ascending aortic replacement surgery in acute type A aortic dissection patients.

The impact of statins on post-discharge atrial fibrillation after cardiac surgery: Secondary analysis from a randomized trial

Background

Whether statins reliably reduce the risk of postoperative atrial fibrillation (POAF) in patients undergoing cardiac surgery remains controversial. We sought to determine the impact of statin use on new-onset postdischarge POAF in the Post-Surgical Enhanced Monitoring for Cardiac Arrhythmias and Atrial Fibrillation (SEARCH-AF) CardioLink-1 randomized controlled trial.

Methods

We randomized 336 patients with risk factors for stroke (CHA₂DS₂-VASc score ≥ 2) and no history of preoperative atrial fibrillation (AF) to 30-day continuous cardiac rhythm monitoring after discharge from cardiac surgery with a wearable, patched-based device or to usual care. The primary endpoint was the occurrence of cumulative AF and/or atrial flutter lasting for ≥ 6 minutes detected by continuous monitoring, or AF and/or atrial flutter documented by a 12-lead electrocardiogram within 30 days of randomization.

Results

The 260 patients (77.4%) discharged on statins were more likely to be male (P = 0.018) and to have lower CHA₂DS₂-VASc scores (P = 0.011). Patients treated with statins at discharge had a 2-fold lower rate of POAF than those who were not treated with statins in the entire cohort (18.4% vs 8.1%, log-rank P = 0.0076). On multivariable Cox regression including the CHA₂DS₂-VASc score adjustment, statin use was associated with a lower risk of POAF (hazard ratio 0.43, 95% confidence interval: 0.25-0.98, P = 0.043). Use of statins at a higher intensity was associated with lower risk of POAF, suggestive of a dose-response effect (log-rank P _trend = 0.0082).

Conclusions

The use of statins was associated with a reduction in postdischarge POAF risk among patients undergoing cardiac surgery. The routine use of high-intensity statin to prevent subacute POAF after discharge deserves further study.

The Mechanism of Cardiac Sympathetic Activity Assessment Methods: Current Knowledge

This review has summarized the methods currently available for cardiac sympathetic assessment in clinical or under research, with emphasis on the principles behind these methodologies. Heart rate variability (HRV) and other methods based on heart rate pattern analysis can reflect the dominance of sympathetic nerve to sinoatrial node function and indirectly show the average activity level of cardiac sympathetic nerve in a period of time. Sympathetic neurotransmitters play a key role of signal transduction after sympathetic nerve discharges. Plasma or local sympathetic neurotransmitter detection can mediately display sympathetic nerve activity. Given cardiac sympathetic nerve innervation, i.e., the distribution of stellate ganglion and its nerve fibers, stellate ganglion activity can be recorded either directly or subcutaneously, or through the surface of the skin using a neurophysiological approach. Stellate ganglion nerve activity (SGNA), subcutaneous nerve activity (SCNA), and skin sympathetic nerve activity (SKNA) can reflect immediate stellate ganglion discharge activity, i.e., cardiac sympathetic nerve activity. These cardiac sympathetic activity assessment methods are all based on the anatomy and physiology of the heart, especially the sympathetic innervation and the sympathetic regulation of the heart. Technological advances, discipline overlapping, and more understanding of the sympathetic innervation and sympathetic regulation of the heart will promote the development of cardiac sympathetic activity assessment methods.

CD5L, Macrophage Apoptosis Inhibitor, Was Identified in Epicardial Fat-Secretome and Regulated by Isoproterenol From Patients With Heart Failure

Objectives

Neurohormonal dysfunction, which can regulate epicardial fat activity, is one of the main promoters of atrial fibrillation (AF) in patients with heart failure (HF). Our aim was to study the epicardial fat mediators for AF in patients with HF and its catecholaminergic regulation.

Methods

We have included 29 patients with HF who underwent cardiac surgery and were followed up for 5 years. Released proteins by epicardial adipose tissue (EAT) after isoproterenol treatment were identified by nano-high-performance liquid chromatography (HPLC) and triple time-of-flight (TOF) analysis. Common and differential identified proteins in groups of patients with AF before and after surgery were determined by the FunRich tool. Plasma and epicardial fat biopsy proteins were quantified by western blot.

Results

Our results identified 17 common released proteins by EAT, after isoproterenol treatment, from HF patients who suffered AF or developed new-onset AF during follow-up. Mostly, they were involved on inflammatory response and extracellular matrix. One of them was CD5L, a macrophage apoptosis inhibitor. Its secretion by isoproterenol treatment was validated on western blot. The CD5L levels on epicardial fat were also higher in the group of male patients who present or develop AF (0.44 ± 0.05 vs. 0.18 ± 0.15; p < 0.016). However, there were no differences regarding plasma levels.

Conclusion

Our results suggest the role of epicardial fat CD5L as a mediator of AF and its possible paracrine effect by catecholaminergic activity.

Highly sensitive LC-MS/MS analysis of catecholamines in plasma

The catecholamines, epinephrine (E) and norepinephrine (NE) are important both as neurotransmitters and hormones, and measurement of E and NE in plasma is therefore of great interest in medical research. However, the low concentrations of E and NE in plasma require an analysis method that is both specific and sensitive. Plasma sample E and NE were extracted using solid phase extraction, and analyzed by an in-sample ion-pairing chromatography (IPC) LC-MS/MS method, that enables the ion-pairing reagent to be diverted to waste without entering the ion source of the mass spectrometer. The method was validated with good performance characteristics and the limit of quantification (LOQ) was found to be 0.20 and 0.02 nmol/L for NE and E, respectively. In conclusion, this work presents development and validation of a method for determining E and NE in plasma with a measuring range covering the entire reference interval for human plasma.

Cardiovascular Risks and Organ Damage in Secondary Hypertension

Secondary hypertension is associated with increased cardiovascular risk and exaggerated target organ damage, not only due to the higher and more sustained blood pressure values often observed in these patients but also because certain forms of hypertension can increase cardiovascular risk and organ damage by the neurohormonal and/or molecular pathways activation they exert. Early identification of secondary forms of hypertension can help mitigate organ damage and prevent cardiovascular complications. Signs and symptoms distinction among types of secondary hypertension is essential in order to prevent complications.

Clinical Risk Factors for Postoperative Atrial Fibrillation among Patients after Cardiac Surgery

BACKGROUND

Postoperative atrial fibrillation (POAF) is a common arrhythmia following cardiac surgery and is associated with increased health-care costs, complications, and mortality. The etiology of POAF is incompletely understood and its prediction remains suboptimal. Using data from published studies, we performed a systemic review and meta-analysis to identify preoperative clinical risk factors associated with patients at increased risk of POAF.

METHODS

A systematic search of PubMed, MEDLINE, and EMBASE databases was performed.

RESULTS

Twenty-four studies that reported univariate analysis results regarding POAF risk factors, published from 2001 to May 2017, were included in this meta-analysis with a total number of 36,834 subjects. Eighteen studies were performed in the United States and Europe and 16 studies were prospective cohort studies. The standardized mean difference (SMD) between POAF and non-POAF groups was significantly different (reported as [SMD: 95% confidence interval, CI]) for age (0.55: 0.47-0.63), left atrial diameter (0.45: 0.15-0.75), and left ventricular ejection fraction (0.30: 0.14-0.47). The pooled odds ratios (ORs) (reported as [OR: 95% CI]) demonstrated that heart failure (1.56: 1.31-1.96), chronic obstructive pulmonary disease (1.36: 1.13-1.64), hypertension (1.29: 1.12-1.48), and myocardial infarction (1.18: 1.05-1.34) were significant predictors of POAF incidence, while diabetes was marginally significant (1.06: 1.00-1.13).

CONCLUSION

The present analysis suggested that older age and history of heart failure were significant risk factors for POAF consistently whether the included studies were prospective or retrospective datasets.

Increased risk of atrial fibrillation among patients undergoing coronary artery bypass graft surgery while receiving nitrates and antiplatelet agents

Background Postoperative atrial fibrillation (POAF) is a frequent complication of coronary artery bypass graft (CABG) surgery. This arrhythmia occurs more frequently among patients who receive perioperative inotropic therapy (PINOT). Administration of nitrates with antiplatelet agents reduces the conversion rate of cyclic guanosine monophosphate to guanosine monophosphate. This process is associated with increased concentrations of free radicals, catecholamines, and blood plasma volume. We hypothesized that patients undergoing CABG surgery who receive PINOT may be more susceptible to POAF when nitrates are administered with antiplatelet agents. Methods Clinical records were examined from a prospectively maintained cohort of 4,124 patients undergoing primary isolated CABG surgery to identify POAF-associated factors. Results POAF risk was increased among patients receiving PINOT, and the greatest effect was observed when nitrates were administered with antiplatelet therapy. Adjustment for comorbidities did not substantively change the study results. Conclusions Administration of nitrates with certain antiplatelet agents was associated with an increased POAF risk among patients undergoing CABG surgery. Additional studies are needed to determine whether preventive strategies such as administration of antioxidants will reduce this risk.