Postoperative atrial fibrillation: mechanism, prevention, and future perspective

Efficacy and safety of sacubitril/valsartan on postoperative atrial fibrillation in adult patients undergoing cardiac surgery: a real-world observational study

Background

The mechanism underlying new-onset postoperative atrial fibrillation (POAF) in adult cardiac surgery is not well understood. However, efficient pharmacological methods to prevent and treat arrhythmic complications are still lacking. In the present study, we explored the efficacy and safety of sacubitril/valsartan (sac/val) in the control of POAF in adult cardiac surgery patients.

Methods

Between January 2021 and December 2021, 667 eligible adult patients who underwent cardiac surgery at the Affiliated Hospital of Qingdao University were enrolled. The participants were divided into two groups according to whether sac/val was used: the sac/val group (N = 101) and the control group (N = 566). The main observational endpoints were the incidence of POAF, left ventricular ejection fraction (LVEF) recovery, in-hospital mortality, and short-term mortality.

Results

Patients in the sac/val group had a lower incidence of POAF than those in the control group (26/101 vs. 204/566, P = 0.045). Patients in the sac/val group also showed a higher communicative risk for POAF incidence using the Kaplan-Meier survival analysis. In addition, patients in the sac/val group showed better LVEF recovery, with dynamic changes in LVEF superior to that of the control group. The change in LVEF in the sac/val group was 1.78 ± 5.41, compared with -1.19 ± 10.92 in the control group (P = 0.008).

Conclusions

This is the first observational study to evaluate the efficacy and safety of sac/val in the prevention and treatment of POAF after cardiac surgery. The results demonstrated that compared with patients who did not receive sac/val treatment, those who received Sac/val treatment showed better POAF control and LVEF recovery. These results should be cautiously interpreted and further confirmed using larger sample sizes and prospective randomized controlled trials.

Predicting postoperative atrial fibrillation after cardiac surgery using the Naples prognostic score

INTRODUCTION

The Naples prognostic score (NPS) is a novel indicator of nutritional and inflammatory statuses in cancer patients. Development of atrial fibrillation after cardiac surgery (POAF) is a common complication that increases the incidence of adverse events. Numerous studies have investigated predictors of POAF. Yet, this study is the first to evaluate the prognostic value of NPS in predicting the development of POAF.

MATERIALS AND METHODS

The population of this retrospective single-center case-control study consisted of all consecutive patients who underwent cardiac surgery between January 2021 and December 2023. The patients included in the study sample were divided into two groups according to whether they had POAF (group POAF) or remained in sinus rhythm (group RSR). Univariate and multivariate analyses were conducted to identify the variables that significantly predicted the development of POAF.

RESULTS

This study consisted of 860 patients with a mean age of 61.77 ± 9.13 years and 77.5% (n = 667) were male. The incidence of POAF in the sample was 24.8% (n = 214). NPS was significantly higher in group POAF than in group RSR (2.18 ± 0.99 vs. 1.96 ± 1.02, P = 0.008). Multivariate analysis revealed age [odds ratio (OR): 1.242, 95% confidence interval (CI): 1.020-1.304, P < 0.001] and high NPS (OR: 1.698, 95% CI: 1.121-1.930, P < 0.010) as independent predictors of POAF.

CONCLUSION

High NPS values, along with advanced age, were found to be strongly associated with an increased risk of developing POAF. Therefore, it is concluded that NPS is a significant and independent predictor of POAF in patients undergoing cardiac surgery.

Myocardial Blush Grade Predicts Postoperative Atrial Fibrillation following Mitral Valve Replacement: A Novel Perspective

Background: Atrial fibrillation (AF) remains the most common arrhythmia following mitral valve surgery. Although numerous clinical and laboratory indicators and possible mechanisms of postoperative AF (PoAF) have been described, the role of microvascular dysfunction in pathogenesis has not been assessed. We aimed to evaluate the association between microvascular dysfunction and PoAF in patients undergoing isolated mitral valve replacement. Methods: 188 patients undergoing mitral valve replacement were included in this retrospective study. Demographic characteristics of the patients were recorded. Angiographic assessment of microvascular perfusion was performed using the myocardial blush grading technique for each patient. Univariate and multivariate logistic regression analyses were utilized to determine predictors of PoAF. Results: Of 188 patients (56.69 ± 8.9 years, 39.4% male) who underwent mitral valve replacement, 64 (34%) patients developed PoAF. In the PoAF group, a lower basal hemoglobin level (12.64 ± 0.89 vs. 14.46 ± 0.91 g/dL; p < 0.001), a higher left atrial diameter [5.9 (5.2-6.47) vs. 4.9 (4.5-5.8) cm; p < 0.001], and a lower total blush score (TBS) (8.33 ± 0.84 vs. 8.9 ± 0.31; p < 0.001) were detected. Multivariate logistic regression analysis revealed that preoperative LA diameter (OR:2.057; 95% CI: 1.166-3.63; p = 0.013), preoperative hemoglobin (OR:0.12; 95% CI: 0.058-0.245; p < 0.001), and abnormal TBS (OR:15.1; 95% CI: 1.602-142.339; p = 0.018) were independent predictors of PoAF. Conclusions: Our findings demonstrated that TBS at the preoperative period was an independent predictor of PoAF in patients undergoing isolated mitral valve replacement.

Effects of different doses of glucocorticoids on postoperative atrial fibrillation: a meta-analysis

BACKGROUND

Postoperative atrial fibrillation (POAF) is the most common arrhythmia after cardiac surgery, and its occurrence is closely related to inflammation. This paper intends to apply meta-analysis to investigate the effect of glucocorticoids on POAF.

METHODS

PubMed, Embase, Web of Science, and Cochrane Library were searched using the internationally recognized systematic evaluation and retrieval strategy. Two review authors independently selected relevant studies and extracted data based on the Cochrane handbook for systematic reviews of interventions approach. Stata 17 was used for data analysis. In the subgroup analysis, we grouped the participant data according to differences in glucocorticoids dose and type of surgery. At the same time, we also conducted a meta-analysis on the possible infection and gastrointestinal injury caused by glucocorticoids use.

RESULTS

27 studies and 14,442 patients were finally included. Results from the random-effects model indicated that the incidence of POAF was lower in glucocorticoid group (RR 0.80, 95% CI 0.71-0.92, P = 0.001). According to the subgroup analysis result, low doses of glucocorticoids reduced the incidence of POAF (RR 0.81, 95% CI 0.71-0.92, P = 0.001). The effect of high doses glucocorticoids on the POAF was not statistically significant (RR 0.81, 95% CI 0.56-1.19, P = 0.286). In the coronary artery bypass grafting (CABG) subgroup, the glucocorticoids reduced the incidence of POAF (RR 0.71, 95% CI 0.58-0.87, P = 0.001). In the CABG OR Valvular Surgery group, the effect of glucocorticoids on POAF was not statistically significant (RR 0.88, 95% CI 0.75-1.03, P = 0.108). 15 studies documented postoperative complications of infection, two studies were excluded from the system because the end point event was 0, and meta-analysis showed no increased risk of infection from glucocorticoid use (RR 0.85, 95% CI 0.68-1.06, P = 0.158). Eight studies documented the effects of glucocorticoids on gastrointestinal diseases, and meta-analysis showed no differences between the two groups (RR 1.12, 95% CI 0.83-1.50, P = 0.450).

CONCLUSION

The use of glucocorticoids can reduce the incidence of POAF. The subgroup analysis result showed that low-dose glucocorticoids were more effective than high-dose glucocorticoids in inhibiting POAF. The use of glucocorticoids in CABG alone can better inhibit the occurrence of POAF. The effects of glucocorticoids on infection and gastrointestinal injury were not statistically significant.

REVIEW REGISTRATION

PROSPERO, CRD42022304521.

Dose-dependent scavenging activity of the ultra-short-acting β1-blocker landiolol against specific free radicals

Landiolol, a highly cardioselective ultra-short-acting β1-blocker, prevents perioperative atrial fibrillation associated with systemic inflammation and oxidative stress. We evaluated the direct scavenging activity of landiolol against multiple free radical species. Nine free radical species (hydroxyl, superoxide anion, ascorbyl, tert-butyl peroxyl, tert-butoxyl, singlet oxygen, 2,2-diphenyl-1-picrylhydrazyl, nitric oxide, and tyrosyl radicals) were directly quantified using an X-band ESR spectrometer with the spin-trapping method. IC50 and reaction rate constants were estimated from the dose-response curve for each free radical. Landiolol scavenged six of the free radical species examined: hydroxyl radical (IC50 = 0.76 mM, k landiolol = 1.4 × 10‍10 M‍-1 s‍-1, p<0.001), superoxide anion (58 mM, 2.1 M‍-1 s‍-1, p = 0.044), tert-butoxyl radical (4.3 mM, k landiolol/k CYPMPO = 0.77, p<0.001), ascorbyl free radical (0.31 mM, p<0.001), singlet oxygen (0.69 mM, k landiolol/k 4-OH ‍TEMP = 2.9, p<0.001), and nitric oxide (15 mM, 1.7 × 10 M‍-1 s‍-1, p<0.001). This study is the first to report that landiolol dose-dependently scavenges multiple free radical species with different reaction rate constants. These results indicate the potential clinical application of landiolol as an antioxidative and anti-inflammatory agent in addition to its present clinical use as an anti-arrhythmic agent.

Neurological Complications of Cardiac Procedures

Neurological complications after cardiac surgery and percutaneous cardiac interventions are not uncommon. These include periprocedural stroke, postoperative cognitive dysfunction after cardiac surgery, contrast-induced encephalopathy after percutaneous interventions, and seizures. In this article, we review the incidence, pathophysiology, diagnosis, and management of these complications. Improved understanding of these complications could lead to their prevention, faster detection, and facilitation of diagnostic workup and appropriate treatment.

Clinical significance of postoperative atrial arrhythmias in patients who underwent lung transplantation

BACKGROUND/AIMS

Atrial arrhythmia (AA) occasionally occurs after lung transplantation (LT); however, risk factors for AA and their impact on clinical outcomes are inconsistent. We aimed to investigate the incidence, predisposing factors, and clinical outcomes of AA after LT.

METHODS

We retrospectively evaluated 153 consecutive patients who underwent LT between January 2010 and August 2016. An AA episode was defined as a documented atrial fibrillation (AF), atrial flutter, or atrial tachycardia on 12-lead electrocardiography or episodes lasting ≥ 30 seconds on telemetry monitoring.

RESULTS

The mean follow-up time was 22.0 ± 19.1 months. Postoperative AA occurred in 46 patients (30.1%) after LT. Patients with postoperative AA were older, had larger body surface area, and had an increased incidence of paroxysmal AF prior to transplantation, idiopathic pulmonary fibrosis, and postoperative tracheostomy than patients without AA. Preoperative right atrial pressure (RAP) (odds ratio [OR], 1.19; p = 0.005) and longer periods of mechanical ventilation (OR, 1.03; p = 0.008) were found to be independent risk factors for AA after surgery. Development of AA was a significant predictor of long-term overall mortality (hazard ratio, 2.75; p = 0.017).

CONCLUSION

Patients with elevated preoperative RAP and long-term ventilator care had a higher risk of AA after LT. Further, AA after LT was associated with poor long-term survival.

Association of Preoperative Renin-Angiotensin System Inhibitors With Prevention of Postoperative Atrial Fibrillation and Adverse Events: A Systematic Review and Meta-analysis

IMPORTANCE

Postoperative atrial fibrillation (POAF) is a well-known complication after cardiac surgery. Renin-angiotensin system inhibitors (RASIs) have been suggested as an upstream therapy for selected patients with AF; however, evidence in the surgical setting is limited.

OBJECTIVE

To evaluate the role of preoperative RASIs in prevention of POAF and adverse events for patients undergoing cardiac surgery.

DATA SOURCES

The PubMed database and the Cochrane Library from inception until December 31, 2018, were searched by using the keywords renin-angiotensin system inhibitors OR angiotensin-converting enzyme inhibitors OR angiotensin receptor blocker OR aldosterone antagonist AND cardiac surgery. ClinicalTrials.gov was searched from inception until December 31, 2018, by using the keywords postoperative atrial fibrillation.

STUDY SELECTION

Randomized clinical trials (RCTs) and observational studies comparing the association between preoperative RASI treatment vs no preoperative RASI treatment (control group) and the incidence of POAF were identified. Eleven unique studies met the selection criteria.

DATA EXTRACTION AND SYNTHESIS

Pooled analysis was performed using a random-effects model. Sensitivity and subgroup analyses of RCTs were performed to test the stability of the overall effect. Metaregression was conducted to explore potential risk of bias.

MAIN OUTCOMES AND MEASURES

The primary outcome was POAF, and the secondary outcomes included rates of stroke and mortality and duration of hospitalization.

RESULTS

Eleven unique studies involving 27 885 unique patients (74.4% male; median age, 65 years [range, 58.5-74.5 years]) were included. Compared with the control group, the RASI group did not have a significantly reduced risk of POAF (odds ratio [OR], 1.04; 95% CI, 0.91-1.19; P = .55; z = 0.60), stroke (OR, 0.86; 95% CI, 0.62-1.19; P = .37; z = 0.90; without significant heterogeneity, P = .11), death (OR, 1.07; 95% CI, 0.85-1.35; P = .56; z = 0.59; without significant heterogeneity, P = .12), composite adverse cardiac events (OR, 1.04; 95% CI, 0.91-1.18; P = .58; z = 0.56), or a reduced hospital stay (weighted mean difference, -0.04; 95% CI, -1.05 to 0.98; P = .94; z = 0.07) using a random-effects model. Pooled analysis focusing on RCTs showed consistent results. The primary overall effect was maintained in sensitivity and subgroup analyses. Metaregression showed that male sex was significantly associated with POAF (τ2 = 0.0065; z = 3.47; Q = 12.047; P < .001) and that use of β-blockers was associated with a significantly reduced risk in developing POAF (τ2 = 0.018; z = -2.24; Q = 5.0091; P = .03).

CONCLUSIONS AND RELEVANCE

The findings from this study suggest that preoperative RASI treatment does not offer additional benefit in reducing the risk of POAF, stroke, death, and hospitalization in the setting of cardiac surgery. The results provide no support for conventional use of RASIs for the possible prevention of POAF and adverse events in patients undergoing cardiac surgery; further randomized data, particularly among those patients with heart failure, are needed.

Effects of dexmedetomidine on heart arrhythmia prevention in off-pump coronary artery bypass surgery: A randomized clinical trial

Background

Arrhythmia occurring during and after surgery is one of the major complications in open-heart surgery. Dexmedetomidine is an intravenous alpha-2 agonist and very specific short-acting drug to protect the various organs against ischemic injuries and blood reflow. However, the effect of dexmedetomidine for preventing intraoperative heart arrhythmias has not been recognized.

Objective

This study aimed to determine the effect of dexmedetomidine on the incidence rate of heart arrhythmias and anesthetic required in off-pump coronary artery bypass surgery.

Methods

This randomized clinical trial was conducted on patients who were candidates for off-pump coronary artery bypass referring to Imam Reza Hospital of Mashhad, Iran, from July 2016 through January 2017. The patients were randomly assigned to two groups of intervention (infusion of 0.5 mcg/kg/h dexmedetomidine together with induction followed by infusion of 0.5 mcg/kg/h by the end of the surgery) or control (saline infusion). Mean arterial pressure (MAP) and heart rate (HR) were measured before induction, during surgery operation and ICU admission. Data were analyzed by SPSS version 18 using Chi Square and independent-samples t-test.

Results

A total of 76 patients with a mean age of 59.8 ± 8.2 years (in two groups of 38) were studied. The two groups had no statistically significant difference in terms of background variables. The MAP and HR values before induction, during surgery and ICU admission were significantly higher in the control group than in the intervention group (p=0.001). Out of the studied arrhythmias, the values of PAC (55.2% vs. 15.7%), PVC (81.5% vs. 21.0%), AF (26.3% vs. 7.8%), VTAC (21.0% vs. 2.6%) were significantly lower in dexmedetomidine group (p=0.001).

Conclusion

It seems that dexmedetomidine administration during induction and surgery can cause significant reduction in most of the common arrhythmias in off-pump coronary bypass surgery. The use of dexmedetomidine maintains MAP and HR at significantly lower values, and changes compared to the control group as well as reduces the need for anesthetic compounds.

Trial Registration

The present study has been registered at the Iranian Registry of Clinical Trials (www.IRCT.IR) with a code of IRCT2016072413159N9 before starting the study.

Founding

This study was fully sponsored by the Research Deputy at Mashhad University of Medical Sciences, Iran (grant number 941413).

Dexmedetomidine sedation reduces atrial fibrillation after cardiac surgery compared to propofol: a randomized controlled trial

BACKGROUND

Atrial fibrillation occurs frequently in patients following cardiac surgery and can be a cause of increased morbidity and mortality. The use of dexmedetomidine to prevent atrial fibrillation is unclear. The present study was designed to evaluate the effect of dexmedetomidine sedation on the incidence of atrial fibrillation after cardiac surgery.

METHODS

Upon arrival to the intensive care unit (ICU), cardiac surgery patients without prior atrial fibrillation or flutter were randomized to receive either dexmedetomidine (0.2-1.5 μg/kg/h) or propofol (0.3-3 mg/kg/h) open-label titrated to a target Richmond agitation-sedation scale of 0 to -3. Our primary endpoint was the incidence of postoperative atrial fibrillation, and the secondary end points were the length of ICU stay, length of hospital stay, and hospital costs.

RESULTS

Atrial fibrillation occurred in 6 of 44 patients (13.6 %) in the dexmedetomidine group compared to 16 of 44 patients (36.4 %) in the propofol group (odds ratio = 0.28; 95 % confidence interval, 0.10, 0.80; P = 0.025). The median (interquartile range) length of ICU stay in the dexmedetomidine group was significantly lower than in the propofol group (2.9 (2.4-3.5) vs 3.5 (2.7-4.5 days, P = 0.008), with a trend toward a decrease in median hospital costs (86,367 vs 77,874 Chinese yuan; P = 0.068). The incidence of hypotension was higher in the dexmedetomidine group than in the propofol group (25/44 (56.8 %) vs 13/44 (29.5 %); P = 0.017).

CONCLUSIONS

Dexmedetomidine sedation reduced the incidence of new-onset postoperative atrial fibrillation and shortened the length of ICU stay in patients after cardiac surgery compared to propofol sedation. Dexmedetomidine treatment was associated with more episodes of hypotension.

TRIAL REGISTRATION

chictr.org.cn: ChiCTR-IPR-16008231 , retrospectively registered: April 6, 2016. This trial was not prospectively registered due to a lack of importance applied to trial registration.

Atrial arrhythmias after lung transplantation: Incidence and risk factors in 652 lung transplant recipients

OBJECTIVES

Atrial arrhythmia (AA) after lung transplantation (LTx) is a potentially morbid event often associated with increased length of hospital stay. Predictors of postsurgical AA, however, are incompletely understood. We characterized the incidence and predisposing risk factors for AA in patients undergoing LTx.

METHODS

A retrospective analysis of prospectively collected data was conducted to identify LTx recipients between January 2008 and October 2013. Patients were divided into 2 groups on the basis of postoperative AA development. Univariable and multivariable analyses were performed to define differences between groups and identify factors associated with AA. Survival differences were assessed by the use of competing risks methodology.

RESULTS

A total of 198 of 652 (30.4%) patients developed AA at a median onset of 5 days after transplant. Increasing age (hazard ratio [HR] 1.03 per additional year, P < .001) and previous coronary artery bypass grafting (HR 2.77, P = .002) were found to be independent risk factors. Counterintuitively, patients with a medical history of AA before LTx had a lower incidence of postoperative AA. Preoperative beta-blocker usage was not a significant predictor of postoperative AA. Postoperative AA was a significant predictor of long-term mortality (HR 1.63, P = .007) when we adjusted for other risk factors.

CONCLUSIONS

AA is a common occurrence after LTx, occurring with greatest frequency in the first postoperative week, and results in a significant reduction in long-term survival. Increasing age and before coronary artery bypass grafting were identified as independent risk factors for AA development. Better understanding of these risk factors may improve identification of patients at heightened risk after transplantation.

Postoperative arrhythmias after cardiac surgery: incidence, risk factors, and therapeutic management

Arrhythmias are a known complication after cardiac surgery and represent a major cause of morbidity, increased length of hospital stay, and economic costs. However, little is known about incidence, risk factors, and treatment of early postoperative arrhythmias. Both tachyarrhythmias and bradyarrhythmias can present in the postoperative period. In this setting, atrial fibrillation is the most common heart rhythm disorder. Postoperative atrial fibrillation is often self-limiting, but it may require anticoagulation therapy and either a rate or rhythm control strategy. However, ventricular arrhythmias and conduction disturbances can also occur. Sustained ventricular arrhythmias in the recovery period after cardiac surgery may warrant acute treatment and long-term preventive strategy in the absence of reversible causes. Transient bradyarrhythmias may be managed with temporary pacing wires placed at surgery, but significant and persistent atrioventricular block or sinus node dysfunction can occur with the need for permanent pacing. We provide a complete and updated review about mechanisms, risk factors, and treatment strategies for the main postoperative arrhythmias.

Glucocorticoids in adult cardiac surgery; old drugs revisited

Glucocorticoids can play a pivotal role in modulating different immune responses. The role of glucocorticoids in cardiac surgery is still controversial as many surgeons are concerned about the potential side effects.

In this review, we looked at the role of glucocorticoid administration in modulating postoperative inflammatory responses, atrial fibrillation (AF) and intimal hyperplasia and whether glucocorticoid use is associated with a significant increase in undesirable postoperative complication.