Pericardial Blood as a Trigger for Postoperative Atrial Fibrillation After Cardiac Surgery

A posterior pericardial chest tube is associated with reduced incidence of postoperative atrial fibrillation after cardiac surgery: A propensity score-matched study

Objective

Postoperative atrial fibrillation (POAF) is a common complication after cardiac surgery that is associated with other adverse outcomes. Recent studies have shown that drainage of pericardial effusion by a posterior pericardial incision reduces the incidence of POAF. An alternative approach is a chest tube placed posteriorly in the pericardium. We evaluated whether the use of a posterior pericardial drain was associated with reduced risk of POAF in patients undergoing coronary artery bypass graft (CABG) and/or aortic valve replacement (AVR).

Methods

This observational study included 2535 patients who underwent CABG (n = 1997), AVR (n = 293), or combined CABG and AVR (n = 245) in Iceland from 2002 to 2020. From our study population, 553 (22%) received a 20-Fr posterior pericardial chest tube in addition to standard mediastinal and left pleural drains. The incidence of POAF in patients with and without a posterior pericardial drain was compared before and after 1:1 propensity score matching.

Results

Of 2535 patients, 1100 were included in the matched cohort. The incidence of POAF was lower in patients receiving posterior pericardial chest tube drainage compared with the control group, both before (34% vs 43%, P < .001) and after (33% vs 43%, P = .002) matching. In a multivariable analysis, posterior pericardial chest tube drainage was independently associated with a reduced risk for POAF (adjusted odds ratio 0.67; 95% confidence interval, 0.52-0.88; P = .003).

Conclusions

This observational study suggested that posterior pericardial chest tube drainage is associated with a significant reduction of POAF after routine CABG and/or AVR procedures. The results are hypothesis-generating and must be confirmed in prospective randomized trials.

Posterior cardiac drain for atrial fibrillation after aortic valve replacement

Background

Postoperative atrial fibrillation occurs in 27% to 40% of patients after cardiac surgery. One cause of postoperative atrial fibrillation is pericardial effusion, which can be a significant source of inflammation. In this study, we investigated the effect of a drain placed in a posterior site to the heart to reduce pericardial effusion in the early postoperative period to prevent postoperative atrial fibrillation.

Methods

Participants were patients who underwent initial standby aortic valve replacement at Saga-Ken Medical Centre Koseikan from January 2010 to December 2021. Patients with a history of atrial fibrillation, complex surgery, or emergency surgery were excluded. The patients were divided into two groups: those with a posterior cardiac drain in addition to the usual intrapericardial and subpleural drains from September 2017 (group P) and those without posterior cardiac drain from January 2010 to August 2017 (group N). Multiple logistic regression analysis was performed to evaluate the usefulness of posterior cardiac drain.

Results

Of the 79 patients included the study, 40 were male and groups P and N comprised 27 and 52 patients, respectively. Of the 79 patients, 32 developed postoperative atrial fibrillation; among whom, 7/27 (25.9%) had posterior cardiac drain and 25/52 (48.1%) had no posterior cardiac drain (p = 0.09). When adjusted for body surface area, left ventricular end-diastolic and left atrial diameter, the incidence of postoperative atrial fibrillation was significantly lower in group P than in group N (adjusted odds ratio 0.270, 95% confidence interval 0.077-0.953, p = 0.042). Furthermore, no patient in the group P underwent postoperative thoracentesis in the subanalysis.

Conclusions

The results suggest that early postoperative reduction of pericardial effusion by posterior cardiac drain placement may reduce the incidence of postoperative atrial fibrillation.

Cardiac Arrhythmias in Trauma Patients Undergoing Pericardiotomy: A Retrospective Analysis

INTRODUCTION

Pericardiotomy is performed in the setting of trauma to diagnose and treat cardiac injury. The frequency of cardiac arrhythmia after pericardiotomy for trauma is poorly described in the literature. We sought to identify the frequency of and risk factors for the development of postpericardiotomy arrhythmia in trauma patients.

MATERIALS AND METHODS

We performed a retrospective single-center cohort study of patients >16 y of age, querying our institutional trauma database (Jan 2011-Dec 2020) for International Classification of Diseases-9 and -10 codes involving pericardiotomy (i.e., pericardial window, sternotomy). Operative details and postoperative course were collected for patients surviving >24 h. Sinus bradycardia and tachycardia were not included as arrhythmias.

RESULTS

We identified 252 trauma patients who underwent pericardiotomy. One hundred fifty-four patients survived >24 h. Of these, 12.3% experienced arrhythmia. Patients developing arrhythmia were older, had higher injury severity score, were more likely to have a blunt mechanism of injury, and had higher in-hospital mortality. On multiple logistic regressions, increasing age, blunt mechanism, and concomitant laparotomy were associated with arrhythmia development, while operative characteristics were not.

CONCLUSIONS

At our institution, trauma patients undergoing pericardiotomy have a risk of arrhythmia of 12.3%, which is associated with multiple nonmodifiable risk factors. Further study is warranted to identify potential mechanisms to reduce arrhythmias in this population.

Postoperative Atrial Fibrillation Prediction by Left Atrial Size in Coronary Artery Bypass Grafting and Five-Year Survival Outcome

Background: Postoperative Atrial Fibrillation (POAF) is a common complication in cardiac surgery. Despite its multifactorial origin, the left atrial (LA) size is closely linked to POAF, raising the question of a valid cut-off value and its impact on the long-term outcome. Methods: Patients without a history of AF who underwent coronary artery bypass grafting between 2014 and 2016 were selected for this retrospective study. LA size was preoperatively assessed using the left atrial anterior-posterior diameter (LAAPd). Correlation and logistic regression analyses were performed, following a receiver-operating characteristic (ROC) analysis. Propensity score matching (PSM) was applied to ensure group comparability, followed by a comparison analysis regarding the primary endpoint of POAF and the secondary endpoints of all-cause mortality and stroke during a five-year follow-up. Results: A total of 933 patients were enrolled in the study eventually revealing a significant correlation between LAAPd and POAF (cor = 0.09, p < 0.01). A cut-off point of 38.5 mm was identified, resulting in groups with 366 patients each after PSM. Overall, patients with a dilated LA presented a significantly higher rate of POAF (22.3% vs. 30.4%, p = 0.02). In a five-year follow-up, a slightly higher rate of all-cause mortality (9.8% vs. 13.7%, HR 1.4 [0.92-2.29], p = 0.10) was observed, but there was no difference in the occurrence of strokes (3.6% vs. 3.3%, p = 0.87). Conclusions: An LAAPd of >38.5 mm was found to be an independent predictor of POAF after coronary artery bypass grafting and resulted in a non-significant tendency towards a worse outcome regarding all-cause mortality in a five-year follow-up.

Left atrial volume index and interleukin-6 as predictors for postoperative atrial fibrillation

BACKGROUND

Postoperative atrial fibrillation (POAF) is a common complication after cardiac surgery. However, the predictive value of single indictor still remains controversial. This study aimed to assess the predictive value of combining preoperative left atrial volume index (LAVI) and postoperative interleukin-6 (IL-6) for POAF in the patients receiving cardiac surgery.

METHODS

Patients who admitted to Nanjing First Hospital during the study period between December 2022 and June 2023, and underwent open-heart surgery without a history of atrial fibrillation (AF) were enrolled. The relationships between predictors and POAF were investigated using logistic regression analysis. We determined the combined predictive value of LAVI and IL-6 for POAF by measuring the changes in the area under the receiver operating characteristic curve (AUC) and calculating the net reclassification improvements (NRIs) and integrated discrimination improvement (IDIs).

RESULTS

102 patients were enrolled in this study, and 50 participants developed POAF (49.0%). Patients who experienced POAF had higher levels of preoperative LAVI and postoperative IL-6 than those who did not. Regression analysis revealed that larger LAVI and higher level of IL-6 were independently associated with increased risk of POAF. The combined addition of LAVI and IL-6 to the predictive model resulted in an evident increase in the AUC. Incorporating both LAVI and IL-6 increased IDIs in all models.

CONCLUSION

Our results demonstrated that combined LAVI and IL-6 achieved a higher prediction performance for POAF.

The role of pericardial fluid biomarkers in predicting post-operative atrial fibrillation, a comprehensive review of current literature

Post-operative atrial fibrillation (POAF) is a common complication of cardiac surgery which is associated with longer hospital stay, diminished quality of life, and increased mortality. Yet, the pathophysiology of POAF is poorly understood and it is unclear which patients are at highest risk. Pericardial fluid (PCF) analysis is emerging as an important tool for the early detection of biochemical and molecular changes in the cardiac tissue. With the epicardium acting as a semi-permeable membrane, the composition of PCF reflects the activity of the cardiac interstitium. Emerging research on PCF composition has identified promising biomarkers which may help stratify the risk for developing POAF. These include inflammatory molecules, such as interleukin-6, mitochondrial deoxyribonucleic acid, and myeloperoxidase, as well as natriuretic peptides. Additionally, PCF appears to be superior to serum analysis in detecting changes in these molecules during the early postoperative period after cardiac surgery. The aim of the present narrative review is to summarize the current literature on the temporal changes in the levels of potential biomarkers in PCF after cardiac surgery and their association with the development of new-onset postoperative atrial fibrillation.

Posterior pericardiotomy and the prevention of post-operative atrial fibrillation and cardiac tamponade in isolated coronary artery bypass grafting - A retrospective analysis

BACKGROUND

Post-Operative Atrial Fibrillation (POAF) is the most frequent complication of cardiac surgery and is associated with reduced survival, increased rates of cognitive changes and cerebrovascular accidents, heart failure, renal dysfunction, infection, length of stay and hospital costs. Cardiac tamponade although less common, carries high morbidity and mortality. Shed mediastinal blood in the pericardial space is a major source of intrapericardial oxidative stress and inflammation that triggers POAF. The utilisation of a posterior pericardiotomy (PP) aims to shunt blood from pericardium into the pleural space and have a role in the prevention of POAF as well as cardiac tamponade.

METHODS

2168 patients had undergone isolated Coronary Artery Bypass Grafting at Royal Hobart Hospital from 2008 to 2022. They were divided into PP group vs. control group. Patient baseline demographics, intraoperative data and post-operative outcomes were reviewed retrospectively.

RESULTS

Total incidence of new POAF and cardiac tamponade was 24% and 0.74% respectively. Primary outcome of both the incidence of POAF (20.2% vs. 26.3%, p < 0.05) and Cardiac Tamponade (0% vs. 1.1%, p < 0.05) were less in the pericardiotomy group. A subgroup analysis of patients with recent myocardial infarction showed reduced incidence of POAF in the PP group (p < 0.05). Increasing age, Body Mass Index, poor left ventricular ejection fraction (EF < 30%) and return to theatre were independent predictors of developing POAF. There were similar rates of return to theatre for bleeding however, no cases of tamponade in the pericardiotomy group. There were no complications attributable to left posterior pericardiotomy and the time added to the duration of surgery was minimal.

CONCLUSION

Posterior pericardiotomy is associated with a significant reduction in the incidence of POAF and cardiac tamponade which is safe and efficient.

Enhanced recovery after cardiac surgery: A literature review

Enhanced recovery after cardiac surgery (ERACS) represents a constellation of evidence-based peri-operative methods aimed to reduce the physiological and psychological stress patients experience after cardiac surgery, with the primary objective of providing an expedited recovery to pre-operative functional status. The method involves pre-operative, intra-operative, and post-operative interventions as well as direct patient engagement to be successful. Numerous publications in regard to the benefits of enhanced recovery have been presented, including decreased post-operative complications, shortened length of stay, decreased overall healthcare costs, and higher patient satisfaction. Implementing an ERACS program undeniably requires a culture change, a methodical shift in the approach of these patients that ultimately allows the team to achieve the aforementioned goals; therefore, team-building, planning, and anticipation of obstacles should be expected.

Association Between Serum Levels of Nicotinamide-Adenine Dinucleotide Phosphate Oxidase 2 and the Development of Atrial Fibrillation After Isolated Coronary Artery Bypass Grafting: A Prospective Pilot Study

INTRODUCTION

To investigate the levels of nicotinamide-adenine dinucleotide phosphate oxidase 2 (NOX2) in serum and pericardial drainage samples in the early stage after coronary artery bypass grafting (CABG) and determine whether NOX2 is predictive of postoperative atrial fibrillation (POAF).

MATERIALS AND METHODS

This prospective pilot study involved 152 adults without history of atrial fibrillation who underwent first-time elective isolated CABG. Serum and pericardial fluid samples were simultaneously obtained from patients at baseline and 4, 12, and 24 h post operation. NOX2 levels were determined using enzyme-linked immunosorbent assays. The heart rhythm of patients was continuously monitored through a Holter monitor until discharge. Logistic regression and receiver-operating characteristic (ROC) curve analyses were performed, as appropriate.

RESULTS

Fifty-one patients (33.6%) experienced in-hospital POAF. NOX2 concentration in serum and pericardial drainage samples was increased after surgery, reached its peak at 12 h, and gradually declined thereafter toward the baseline levels by 24 h. At 12 h, patients with POAF had higher levels of serum NOX2 than those without (3.96 ± 0.35 vs. 3.70 ± 0.75 μg/mL, respectively, p = 0.004). There were no discernible differences in pericardial NOX2 between the 2 groups. Multivariate analysis revealed that serum NOX2 at 12 h post operation was the strongest independent predictor of POAF (odds ratio: 2.179, 95% confidence interval: 1.084-4.377). The area under the ROC curve of the POAF predictive model was 0.732 (95% confidence interval: 0.654-0.801).

CONCLUSION

Serum NOX2 may be useful in the identification of POAF. Larger studies are warranted to substantiate these findings.

Cardiac surgery elicits pericardial inflammatory responses that are distinct compared with postcardiopulmonary bypass systemic inflammation

Objectives

Cardiac surgery using cardiopulmonary bypass contributes to a robust systemic inflammatory process. Local intrapericardial postsurgical inflammation is believed to trigger important clinical implications, such as postoperative atrial fibrillation and postsurgical intrathoracic adhesions. Immune mediators in the pericardial space may underlie such complications.

Methods

In this prospective pilot clinical study, 12 patients undergoing isolated coronary artery bypass graft surgery were enrolled. Native pericardial fluid and venous blood samples (baseline) were collected immediately after pericardiotomy. Postoperative pericardial fluid and venous blood samples were collected 48-hours after cardiopulmonary bypass and compared with baseline. Flow cytometry determined proportions of specific immune cells, whereas multiplex analysis probed for inflammatory mediators.

Results

Neutrophils are the predominant cells in both the pericardial space and peripheral blood postoperatively. There are significantly more CD163lo macrophages in blood compared with pericardial effluent after surgery. Although there are significantly more CD163hi macrophages in native pericardial fluid compared with baseline blood, after surgery there are significantly fewer of these cells present in the pericardial space compared with blood. Postoperatively, concentration of interleukin receptor antagonist 6, and interleukin 8 were significantly higher in the pericardial space compared with blood. After surgery, compared with blood, the pericardial space has a significantly higher concentration of matrix metalloproteinase 3, matrix metalloproteinase 8, and matrix metalloproteinase 9. The same trend was observed with transformational growth factor β.

Conclusions

Cardiac surgery elicits an inflammatory response in the pericardial space, which differs from systemic inflammatory responses. Future work should determine whether or not this distinct local inflammatory response contributes to postsurgical complications and could be modified to influence clinical outcomes.

The Effect of Posterior Pericardiotomy on the Incidence of Atrial Fibrillation After Cardiac Surgery-Extended Follow-Up study (PALACS-EF): rationale and design

Aims

Postoperative atrial fibrillation (POAF) is the most common complication of cardiac surgery and has been associated with increased postoperative morbidity and hospital costs. The Posterior left pericardiotomy for the prevention of AtriaL fibrillation After Cardiac Surgery (PALACS) trial found that posterior pericardiotomy significantly reduced the incidence of POAF (17% vs. 32%, P < 0.001). We present the protocol for The Effect of Posterior Pericardiotomy on the Incidence of Atrial Fibrillation After Cardiac Surgery-Extended Follow-Up study (PALACS-EF): a prospective, extended follow-up of the original PALACS trial. The aim of PALACS-EF is to gain more data regarding the effect of posterior pericardiotomy on postdischarge clinical outcomes. The primary outcome is the time to the first occurrence of the composite of all-cause mortality or hospital cardiovascular readmission. The key secondary outcome is the time to the first occurrence of the composite of all-cause mortality and all-cause hospital readmission. Hospital readmission, myocardial infarction, stroke, transient ischaemic attack, heart failure, systemic embolism, or new arrhythmias with onset since 30-day follow-up will also be recorded.

Methods and results

All 420 patients enrolled in the PALACS trial will be included; extended follow-up will be conducted via telephone by blinded research personnel utilizing a standardized script to ensure uniformity and completeness of follow-up. If an event has occurred, documentation will be obtained, and an independent adjudication committee blinded to group assignment will adjudicate outcome events. Results will be reported when a median follow-up of 5 years is achieved.

Conclusion

PALACS-EF will provide data to answer the question of whether posterior pericardiotomy improves postdischarge outcomes in patients undergoing cardiac surgery, and it will provide information on the relationship between POAF and adverse postdischarge outcomes including mortality, hospitalization, heart failure, and stroke.

Registration

PALACS: NCT02875405, PALACS-EF: NCT05903222.

Pericardial Inflammatory Mediators That Can Drive Postoperative Atrial Fibrillation in Cardiac Surgery Patients

Postoperative atrial fibrillation (POAF) is a common dysrhythmia that affects a significant number of patients undergoing cardiac surgery. Many studies aim to better understand this complex postsurgical complication by analysing circulating biomarkers in patients who develop POAF. More recently, the pericardial space was shown to contain inflammatory mediators that could trigger POAF. In this review we summarise recent studies that examine the immune mediators present in the pericardial space and their potential implications for the pathophysiology of POAF in cardiac surgery patients. Ongoing research in this area should better delineate the multifactorial etiology of POAF, where specific markers may be targeted to reduce the incidence of POAF and improve outcomes for this patient population.

Construction and validation of a nomogram of risk factors for new-onset atrial fibrillation in advanced lung cancer patients after non-surgical therapy

Objective

Risk factors of new-onset atrial fibrillation (NOAF) in advanced lung cancer patients are not well defined. We aim to construct and validate a nomogram model between NOAF and advanced lung cancer.

Methods

We retrospectively enrolled 19484 patients with Stage III-IV lung cancer undergoing first-line antitumor therapy in Shanghai Chest Hospital between January 2016 and December 2020 (15837 in training set, and 3647 in testing set). Patients with pre-existing AF, valvular heart disease, cardiomyopathy were excluded. Logistic regression analysis and propensity score matching (PSM) were performed to identify predictors of NOAF, and nomogram model was constructed and validated.

Results

A total of 1089 patients were included in this study (807 in the training set, and 282 in the testing set). Multivariate logistic regression analysis showed that age, c-reactive protein, centric pulmonary carcinoma, and pericardial effusion were independent risk factors, the last two of which were important independent risk factors as confirmed by PSM analysis. Nomogram included independent risk factors of age, c-reactive protein, centric pulmonary carcinoma, and pericardial effusion. The AUC was 0.716 (95% CI 0.661-0.770) and further evaluation of this model showed that the C-index was 0.716, while the bias-corrected C-index after internal validation was 0.748 in the training set. The calibration curves presented good concordance between the predicted and actual outcomes.

Conclusion

Centric pulmonary carcinoma and pericardial effusion were important independent risk factors for NOAF besides common ones in advanced lung cancer patients. Furthermore, the new nomogram model contributed to the prediction of NOAF.

Postoperative pericardial effusion, pericardiotomy, and atrial fibrillation: An explanatory analysis of the PALACS trial

BACKGROUND

In the Posterior left pericardiotomy for the prevention of atrial fibrillation after cardiac surgery (PALACS) trial, posterior pericardiotomy was associated with a significant reduction in postoperative atrial fibrillation (POAF) after cardiac surgery. We aimed to investigate the mechanisms underlying this effect.

METHODS

We included PALACS patients with available echocardiographic data (n = 387/420, 92%). We tested the hypotheses that the reduction in POAF with the intervention was associated with 1) a reduction in postoperative pericardial effusion and/or 2) an effect on left atrial size and function. Spline and multivariable logistic regression analyses were used.

RESULTS

Most patients (n = 307, 79%) had postoperative pericardial effusions (anterior 68%, postero-lateral 51.9%). The incidence of postero-lateral effusion was significantly lower in patients undergoing pericardiotomy (37% vs 67%; P < .001). The median size of anterior effusion was comparable between patients with and without POAF (5.0 [IQR 3.0-7.0] vs 5.0 [IQR 3.0-7.5] mm; P = .42), but there was a nonsignificant trend towards larger postero-lateral effusion in the POAF group (5.0 [IQR 3.0-9.0] vs 4.0 [IQR 3.0-6.4] mm; P = .06). There was a non-linear association between postero-lateral effusion and POAF at a cut-off at 10 mm (OR 2.70; 95% CI 1.13, 6.47; P = .03) that was confirmed in multivariable analysis (OR 3.5, 95% CI 1.17, 10.58; P = 0.02). Left atrial dimension and function did not change significantly after posterior pericardiotomy.

CONCLUSIONS

Reduction in postero-lateral pericardial effusion is a plausible mechanism for the effect of posterior pericardiotomy in reducing POAF. Measures to reduce postoperative pericardial effusion are a promising approach to prevent POAF.

Atrial Fibrillation Occurring During Acute Hospitalization: A Scientific Statement From the American Heart Association

Acute atrial fibrillation is defined as atrial fibrillation detected in the setting of acute care or acute illness; atrial fibrillation may be detected or managed for the first time during acute hospitalization for another condition. Atrial fibrillation after cardiothoracic surgery is a distinct type of acute atrial fibrillation. Acute atrial fibrillation is associated with high risk of long-term atrial fibrillation recurrence, warranting clinical attention during acute hospitalization and over long-term follow-up. A framework of substrates and triggers can be useful for evaluating and managing acute atrial fibrillation. Acute management requires a multipronged approach with interdisciplinary care collaboration, tailoring treatments to the patient's underlying substrate and acute condition. Key components of acute management include identification and treatment of triggers, selection and implementation of rate/rhythm control, and management of anticoagulation. Acute rate or rhythm control strategy should be individualized with consideration of the patient's capacity to tolerate rapid rates or atrioventricular dyssynchrony, and the patient's ability to tolerate the risk of the therapeutic strategy. Given the high risks of atrial fibrillation recurrence in patients with acute atrial fibrillation, clinical follow-up and heart rhythm monitoring are warranted. Long-term management is guided by patient substrate, with implications for intensity of heart rhythm monitoring, anticoagulation, and considerations for rhythm management strategies. Overall management of acute atrial fibrillation addresses substrates and triggers. The 3As of acute management are acute triggers, atrial fibrillation rate/rhythm management, and anticoagulation. The 2As and 2Ms of long-term management include monitoring of heart rhythm and modification of lifestyle and risk factors, in addition to considerations for atrial fibrillation rate/rhythm management and anticoagulation. Several gaps in knowledge related to acute atrial fibrillation exist and warrant future research.

Myeloperoxidase in the pericardial fluid improves the performance of prediction rules for postoperative atrial fibrillation

OBJECTIVES

After surgery, inflammation is a prominent factor influencing postoperative atrial fibrillation. Myeloperoxidase is a major contributor to inflammatory responses after surgical tissue damage. We evaluated whether myeloperoxidase is associated with postoperative atrial fibrillation clinically and in an animal model.

METHODS

This prospective cohort study included patients undergoing isolated coronary artery bypass grafting. Myeloperoxidase concentrations in blood and pericardial fluid were determined at baseline and 6, 12, and 18 hours after coronary artery bypass grafting. Myeloperoxidase activity in blood, pericardial fluid, and atrium were also evaluated in a canine coronary artery bypass grafting model. Electrophysiologic, histologic, and immunohistochemistry analyses were performed to explore underlying mechanisms.

RESULTS

Postoperative atrial fibrillation occurred in 45 of 137 patients (32.8%). Patients with postoperative atrial fibrillation had significantly higher serum and pericardial myeloperoxidase levels. Individual clinical and surgical factors had moderate predictive value (area under the curve, 0.760) for postoperative atrial fibrillation. Discrimination improved remarkably when myeloperoxidase was combined with other parameters (area under the curve, 0.901). Pericardial myeloperoxidase at 6 hours postoperatively was the strongest independent predictor of postoperative atrial fibrillation (odds ratio, 19.215). The rate of postoperative atrial fibrillation increased exponentially across pericardial myeloperoxidase grades. Compared with controls, coronary artery bypass grafting-treated dogs showed higher atrial fibrillation vulnerability and maintenance, shorter atrial effective refractory period, attenuated connexin 43 expression, and increased myocardial and pericardial myeloperoxidase activity. Connexin 43 expression and atrial effective refractory period were strongly negatively correlated with myocardial and pericardial myeloperoxidase activity.

CONCLUSIONS

Myeloperoxidase is linked to postoperative atrial fibrillation, and the ability to predict postoperative atrial fibrillation was remarkably improved by adding pericardial myeloperoxidase. Myeloperoxidase-related atrial structural and electrical remodeling is a physiologic substrate for this arrhythmia.

Intermediate outcomes following arch reconstruction with frozen elephant trunk, a single centre study

BACKGROUND

Surgery on the aortic arch and proximal descending thoracic aorta can be lifesaving but is also associated with significant morbidity, ranging from minor infections to severe neurological impairments as well as a substantial risk of mortality. The aim of this study is to clinically assess outcomes, with special regards to neurologic injury, as well as to seek to identify predictors of in-hospital mortality in two patient groups with different underlying aortic pathology, aneurysms and dissections, undergoing arch/descending aortic repair.

METHODS

34 patients (17 aneurysms, 17 dissections) underwent surgery involving the arch and/or descending aorta, using the Thoraflex or E-Vita frozen elephant trunk graft. 40% were female. Subgroup analysis of aneurysms compared to dissections were performed. Mean follow-up time was 53.9 months and mean age 63.5 years.

RESULTS

In-hospital mortality was 18%. Survival was comparable between aneurysms and dissections. Incidence of spinal cord injury was 9% and stroke 9%. 67% suffered any form of neurological affection, when also cognitive afflictions were included. Perioperative reoperation rate was 29% (bleeding 21%, visceral ischemia 6%, infection 2%), the need for postoperative dialysis was 11% and a series of other minor complications such as atrial fibrillation and pleurocentesis were common.

CONCLUSION

Postoperative dialysis was found to be a predictor of in-hospital mortality, while both dialysis as well as reoperation due to bleeding and/or visceral ischemia increased the risk for overall mortality, irrespective of preoperative diagnosis. Previous or current smoking appeared to be associated with negative outcomes regarding both in-hospital and overall mortality during follow-up. Trial registration Retrospectively enrolled.

Chest Tube Management: Past, Present, and Future Directions for Developing Evidence-Based Best Practices

In the field of modern cardiothoracic surgery, chest drainage has become ubiquitous and yet characterized by a wide variation in practice. Meanwhile, the evolution of chest drain technology has created gaps in knowledge that represent opportunities for new research to support the development of best practices in chest drain management. The chest drain is an indispensable tool in the recovery of the cardiac surgery patient. However, decisions about chest drain management-including those about type, material, number, maintenance of patency, and the timing of removal-are largely driven by tradition due to a scarcity of quality evidence. This narrative review surveys the available evidence regarding chest-drain management practices with the objective of highlighting scientific gaps, unmet needs, and opportunities for further research.

Effect of posterior pericardiotomy in cardiac surgery: A systematic review and meta-analysis of randomized controlled trials

Background

Posterior pericardiotomy (PP) has been shown to reduce the incidence of pericardial effusion and postoperative atrial fibrillation (POAF) after cardiac surgery. However, the procedure and the totality of its effects are poorly known in the cardiac surgery community. We performed a study-level meta-analysis of randomized controlled trials (RCTs) to evaluate the impact of PP in cardiac surgery patients.

Methods

A systematic literature search was conducted on three medical databases (Ovid MEDLINE, Ovid Embase, Cochrane Library) to identify RCTs reporting outcomes of patients that received a PP or no intervention after cardiac surgery. The primary outcome was the incidence of POAF. Key secondary outcomes were operative mortality, incidence of pericardial and pleural effusion, cardiac tamponade, length of stay (LOS), pulmonary complications, amount of chest drainage, need for intra-aortic balloon pump, and re-exploration for bleeding.

Results

Eighteen RCTs totaling 3,531 patients were included. PP was associated with a significantly lower incidence of POAF (odds ratio [OR] 0.45, 95% confidence interval [CI] 0.32-0.64, P < 0.0001), early (OR 0.18, 95% CI 0.10-0.34, P < 0.0001) and late pericardial effusion (incidence rate ratio 0.13, 95% CI 0.06-0.29, P < 0.0001), and cardiac tamponade (risk difference -0.02, 95% CI -0.04 to -0.01, P = 0.001). PP was associated with a higher incidence of pleural effusion (OR 1.42, 95% CI 1.06-1.90, P = 0.02), but not pulmonary complications (OR 0.82, 95% CI 0.56-1.19; P = 0.38). No differences in other outcomes, including operative mortality, were found.

Conclusions

PP is a safe and effective intervention that significantly decreases the incidence of POAF and pericardial effusion following cardiac surgery.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=261485, identifier: CRD42021261485.

Does Active Chest Tube Clearance After Cardiac Surgery Provide Any Clear Benefits?

BACKGROUND

Retained blood syndrome (RBS) encompasses complications, acute and chronic, related to inflammation created by retained intrathoracic blood after cardiac surgery. Reports suggest that active chest tube clearance devices reduce RBS and may lower the rates of reoperation for bleeding and postoperative atrial fibrillation.

METHODS

In a prospective study (April 2015-October 2017), 1367 patients meeting the study inclusion criteria (1113 control subjects with conventional chest tubes and 254 patients with active chest tube clearance devices [the ATC group]) underwent cardiac surgery through primary sternotomy.

RESULTS

Groups were similar in their preoperative and intraoperative characteristics. No differences were found in overall RBS occurrence (4.3% in the ATC group vs 5.3% in the control group; P = .527), including the components of reexploration for bleeding (2.0% [5/254] for the ATC group and 2.4% [27/1113] for the control group; P = .664) and pleural effusion requiring intervention (3.1% [8/254] vs 3.6% [40/1113]; P = .729). Postoperative atrial fibrillation (20.8% [52/254] vs 20.2 % [221/1113]; P = .837) and 30-day mortality were also similar (3.5% vs 2.2%; P = .231). Postoperative blood product use was 31.9% (81/254) in the ATC group and 28.7% (319/1113) in the control group (P = .308). Some complications were more common in the ATC group, including septicemia (2.4% [6/254] vs 0.7% [8/1113]; P = .019) and renal failure (3.9% [10/254] vs 1.7% [19/1113]; P = .026). Median postoperative length of stay was shorter in the ATC group (5 days vs 6 days; P = .025).

CONCLUSIONS

Active chest tube clearance devices were not associated with improved postoperative outcomes related to RBS at the study institution (Northwestern Medicine, Chicago, IL). Given the additional cost, the nursing effort to maintain the active chest tube clearance devices, and the lack of apparent benefit, this study did not demonstrate the value of using such devices in cardiac surgery.

The effect of posterior pericardiotomy after thoracic aortic surgery

Background

Postoperative pericardial effusion is common after cardiovascular surgery. We aimed to examine the effectiveness of posterior pericardiotomy in reducing the incidence of postoperative pericardial effusion and postoperative atrial fibrillation after thoracic aortic surgery.

Methods

This study included 201 patients who underwent thoracic aortic open surgery between January 2014 and November 2021. We compared surgical outcomes between patients who underwent posterior pericardiotomy and those who did not.

Results

The group that did not undergo posterior pericardiotomy had significantly longer mechanical ventilation duration than the group who did, both in the overall (p = 0.005) and in the propensity-matched cohorts (p = 0.001). The lengths of intensive care unit and hospital stays were significantly longer in the group that did not undergo posterior pericardiotomy compared to the group that did, both in the overall and in the propensity-matched cohorts. The occurrence of postoperative atrial fibrillation and stroke did not differ significantly between the two groups. The amount of pericardial drainage was not significantly lower in the group that underwent posterior pericardiotomy in the overall cohorts (p = 0.09), but the difference was significant in the propensity-matched cohorts (p = 0.04). The amount of mediastinal drainage was significantly lower in the group that underwent posterior pericardiotomy, both in the overall cohorts (< 0.001) and in the propensity-matched cohort (< 0.001). Late pericardial tamponade occurred significantly more frequently in the group that did not undergo posterior pericardiotomy than in the group that did, both in the overall (p = 0.03) and in the propensity-matched cohorts (p = 0.03).

Conclusions

Posterior pericardiotomy has no effect on reducing postoperative atrial fibrillation after thoracic aortic surgery. However, posterior pericardiotomy reduced the occurrence of late pericardial tamponade, length of ICU stay, length of hospital stay, and mechanical ventilation duration after surgery.

Pericardial Effusion Provoking Atrial Fibrillation After Cardiac Surgery: JACC Review Topic of the Week

Postoperative atrial fibrillation (POAF) is the most common complication after cardiac surgery. Patients who develop POAF are more likely to experience adverse outcomes, including increased rates of death, stroke, heart failure, and hospitalizations, and higher hospital costs. Understanding the mechanisms underlying POAF is important to improve patients' outcome and optimize health systems' efficiency. Beyond classic pathogenic hypotheses, emerging evidence suggests that postoperative pericardial effusion and localized pericardial inflammation may trigger POAF. This hypothesis is supported by data from nonhuman animal models and a growing body of evidence showing that reducing postoperative pericardial effusion might reduce POAF incidence. In this review, we summarize the classic pathophysiology theories of POAF following cardiac surgery and discuss new etiologic mechanisms with a specific focus on the role of pericardial effusion and inflammation.

Postoperative Atrial Fibrillation Reduced by Intraoperative and Postoperative Cell Saver System in Coronary Artery Bypass Graft Surgery

OBJECTIVE

Postoperative atrial fibrillation is commonly seen after cardiac surgery. One of the contributing factors is mediastinal shed blood and inflammation. Cell salvage techniques can reduce allogenic blood transfusion and reduce inflammation. The aim of this study was to investigate the reduction of postoperative atrial fibrillation by using the cell-salvage system.

METHODS

Patients who underwent isolated coronary artery bypass graft surgery (n = 498) were analyzed retrospectively in 2 groups. Postoperative atrial fibrillation group (n = 75) and non-postoperative atrial fibrillation group (n = 423). Preoperative and postoperative demographic and clini- cal data were compared between the 2 groups, respectively. Postoperative atrial fibrillation and possible contributing factors were analyzed with multinomial logistic regression analysis.

RESULTS

In the postoperative atrial fibrillation group, the patients' age and European System for Cardiac Operative Risk Evaluation (Euroscore) were higher than in the non-postoperative atrial fibrillation group (P = .001 and P = .003, respectively). Postoperative intensive care unit stay and hospital stay were longer in the postoperative atrial fibrillation group than in the non-postoperative atrial fibrillation group (P = .001 and P = .046, respectively). There were no statistical differences in mortality between groups. The incidence of postoperative atrial fibrillation decreased with the use of cell saver system and low Euroscore.

CONCLUSION

The use of a cell salvage device intraoperatively and during the early postoperative period can decrease the incidence of postop- erative atrial fibrillation group.

Non-invasive evaluation of new-onset atrial fibrillation after cardiac surgery: a protocol for the BigMap study

Aims

New‐onset atrial fibrillation (NOAF) is the most common complication after cardiac surgery, occurring in 25–50% of patients. It is associated with post‐operative stroke, increased mortality, prolonged hospital length of stay, and higher treatment costs. Previous small observational studies have identified the left atrium as a source of the electrical rotors and foci maintaining NOAF, but confirmation by a large prospective clinical study is still missing. The aim of the proposed study is to investigate whether the source of NOAF lies in the left atrium. The correct identification of NOAF‐maintaining structures in cardiac surgical patients might offer potential therapeutic targets for prophylactic perioperative ablation strategies.

Methods and results

This is a prospective single‐centre observational study of patients developing NOAF after cardiac surgery. The primary outcome is the description of NOAF‐maintaining structures within the atria. Key secondary outcomes include overall mortality, intensive care unit length of stay, hospital–ventilator‐free days, and proportion of persistent NOAF. In NOAF patients, the non‐invasive electrophysiological mapping will be conducted using a 252‐electrode electrocardiogram vest. After mapping, a low‐dose computed tomography scan of the chest will be performed to integrate the electrophysiological mapping results into a 3D picture of the heart. The study will include approximately 570 patients, of whom 30% (n = 170) are expected to develop NOAF. Sample size calculation revealed that 157 NOAF patients are necessary to assess the primary outcome. Patients will be tracked for a total of 5 years.

Conclusions

This is the largest prospective study to date describing the electrophysiological mechanisms of NOAF using non‐invasive mapping.

Posterior left pericardiotomy for the prevention of atrial fibrillation after cardiac surgery: an adaptive, single-centre, single-blind, randomised, controlled trial

BACKGROUND

Atrial fibrillation is the most common complication after cardiac surgery and is associated with extended in-hospital stay and increased adverse outcomes, including death and stroke. Pericardial effusion is common after cardiac surgery and can trigger atrial fibrillation. We tested the hypothesis that posterior left pericardiotomy, a surgical manoeuvre that drains the pericardial space into the left pleural cavity, might reduce the incidence of atrial fibrillation after cardiac surgery.

METHODS

In this adaptive, randomised, controlled trial, we recruited adult patients (aged ≥18 years) undergoing elective interventions on the coronary arteries, aortic valve, or ascending aorta, or a combination of these, performed by members of the Department of Cardiothoracic Surgery from Weill Cornell Medicine at the New York Presbyterian Hospital in New York, NY, USA. Patients were eligible if they had no history of atrial fibrillation or other arrhythmias or contraindications to the experimental intervention. Eligible patients were randomly assigned (1:1), stratified by CHA₂DS₂-VASc score and using a mixed-block randomisation approach (block sizes of 4, 6, and 8), to posterior left pericardiotomy or no intervention. Patients and assessors were blinded to treatment assignment. Patients were followed up until 30 days after hospital discharge. The primary outcome was the incidence of atrial fibrillation during postoperative in-hospital stay, which was assessed in the intention-to-treat (ITT) population. Safety was assessed in the as-treated population. This study is registered with ClinicalTrials.gov, NCT02875405, and is now complete.

FINDINGS

Between Sept 18, 2017, and Aug 2, 2021, 3601 patients were screened and 420 were included and randomly assigned to the posterior left pericardiotomy group (n=212) or the no intervention group (n=208; ITT population). The median age was 61·0 years (IQR 53·0-70·0), 102 (24%) patients were female, and 318 (76%) were male, with a median CHA₂DS₂-VASc score of 2·0 (IQR 1·0-3·0). The two groups were balanced with respect to clinical and surgical characteristics. No patients were lost to follow-up and data completeness was 100%. Three patients in the posterior left pericardiotomy group did not receive the intervention. In the ITT population, the incidence of postoperative atrial fibrillation was significantly lower in the posterior left pericardiotomy group than in the no intervention group (37 [17%] of 212 vs 66 [32%] of 208 [p=0·0007]; odds ratio adjusted for the stratification variable 0·44 [95% CI 0·27-0·70; p=0·0005]). Two (1%) of 209 patients in the posterior left pericardiotomy group and one (<1%) of 211 in the no intervention group died within 30 days after hospital discharge. The incidence of postoperative pericardial effusion was lower in the posterior left pericardiotomy group than in the no intervention group (26 [12%] of 209 vs 45 [21%] of 211; relative risk 0·58 [95% CI 0·37-0·91]). Postoperative major adverse events occurred in six (3%) patients in the posterior left pericardiotomy group and in four (2%) in the no intervention group. No posterior left pericardiotomy related complications were seen.

INTERPRETATION

Posterior left pericardiotomy is highly effective in reducing the incidence of atrial fibrillation after surgery on the coronary arteries, aortic valve, or ascending aorta, or a combination of these without additional risk of postoperative complications.

FUNDING

None.

A double-blind randomised controlled trial on the effect of Tocovid, a tocotrienol-rich capsule on postoperative atrial fibrillation at the National Heart Institute, Kuala Lumpur: an interim blinded analysis

INTRODUCTION

Post-operative atrial fibrillation (POAF) is associated with poorer outcomes, increased resource utilisation, morbidity and mortality. Its pathogenesis is initiated by systemic inflammation and oxidative stress. It is hypothesised that a potent antioxidant and anti-inflammatory agent such as tocotrienol, an isomer of Vitamin E, could reduce or prevent POAF.

AIMS

The aim of this study is to determine whether a potent antioxidative and anti-inflammatory agent, Tocovid, a tocotrienol-rich capsule, could reduce the incidence of POAF and affect the mortality and morbidity as well as the duration of ICU, HDU and hospital stay.

METHODS

This study was planned as a prospective, randomised, controlled trial with parallel groups. The control group received placebo containing palm superolein while the treatment group received Tocovid capsules. We investigated the incidence of POAF, the length of hospital stay after surgery and the health-related quality of life.

RESULTS

Recruitment commenced in January 2019 but the preliminary results were unblinded as the study is still ongoing. Two-hundred and two patients have been recruited out of a target sample size of 250 as of January 2021. About 75% have completed the study and 6.4% were either lost during follow-up or withdrew; 4% of participants died. The mean age group was 61.44 ± 7.30 years with no statistical difference between the groups, with males having a preponderance for AF. The incidence of POAF was 24.36% and the mean time for developing POAF was 55.38 ± 29.9 h post-CABG. Obesity was not a predictive factor. No statistically significant difference was observed when comparing left atrial size, NYHA class, ejection fraction and the premorbid history. The mean cross-clamp time was 71 ± 34 min and the mean bypass time was 95 ± 46 min, with no difference between groups. There was a threefold increase in death among patients with POAF (p = 0.008) and an increase in the duration of ICU stay (p = 0.01), the total duration of hospital stay (p = 0.04) and reintubation (p = 0.045).

CONCLUSION

A relatively low incidence rate of POAF was noted although the study is still ongoing. It remains to be seen if our prophylactic intervention using Tocovid would effectively reduce the incidence of POAF. Clinical Registration Number: US National Library of Medicine. Clinical Trials - NCT03807037. Registered on 16th January 2019. Link: https://clinicaltrials.gov/ct2/show/NCT03807037.

Mechanism of IL-6-related spontaneous atrial fibrillation after coronary artery grafting surgery: IL-6 knockout mouse study and human observation

Clinical observation and ex vivo studies have established a strong association between inflammation and postoperative atrial fibrillation (POAF). However, it is unclear whether the inflammatory phenotype is causally linked to this event or is an epiphenomenon, and it is not known which inflammatory meditators may increase susceptibility to POAF. The limitations of available animal models of spontaneous POAF (sPOAF) makes it difficult to select an experimental system. Here, we provide experimental and clinical evidence for mechanistic involvement of interleukin-6 (IL-6) in sPOAF.

PHASE I

We established a mouse model of cardiac surgery with nonpaced sPOAF. IL-6 knockout mice were protected from sPOAF compared with wild-type mice.

PHASE II

At 48 hours after surgery, the heart was separated into 6 regions and cultured. IL-6 was expressed in all regions, with highest abundance in the left atrium (LA). In PHASE III, we demonstrated that IL-6 in the LA elicited early profibrotic properties in atria via the pSTAT3/STAT3 signaling pathway and contributed to sPOAF.

PHASE IV

In a translational prospective clinical study, we demonstrated that humans with POAF had a higher IL-6 concentration in pericardial drainage (PD). This study provides preliminary evidence of a causal relationship between IL-6 and POAF in a novel nonpaced sPOAF mouse model. IL-6 is a crucial prerequisite for eliciting profibrotic properties in cardiac myocytes via the pSTAT3 pathway during the early postoperative period, leading to an increased susceptibility to POAF. Measuring IL-6 in PD could be a new noninvasive biomarker for the clinical prediction of POAF.

Active clearance vs conventional management of chest tubes after cardiac surgery: a randomized controlled study

Background

Chest tubes are routinely used after cardiac surgery to evacuate shed mediastinal blood. Incomplete chest drainage due to chest tube clogging can lead to retained blood after cardiac surgery. This can include cardiac tamponade, hemothorax, bloody effusions and postoperative atrial fibrillation (POAF). Prior published non randomized studies have demonstrated that active tube clearance (ATC) of chest tubes can reduce retained blood complications prompting the ERAS Cardiac Society guidelines to recommend this modality.

Objective

A randomized prospective trial to evaluate whether an ATC protocol aimed at improving chest tube patency without breaking the sterile field could efficiently reduce complications related to retained blood after cardiac surgery.

Methods

This was a pragmatic, single-blinded, parallel randomized control trial held from November 2015 to June 2017 including a 30-day post index surgery follow-up. The setting was two academic centers affiliated with the Université de Montréal School of Medicine; the Montreal Heart Institute and the Hôpital du Sacré-Coeur de Montréal. Adult patients admitted for non-emergent coronary bypass grafting and/or valvular heart surgery through median sternotomy, in sinus rhythm for a minimum of 30 days prior to the surgical intervention were eligible for inclusion.

In the active tube clearance group (ATC), a 28F PleuraFlow device was positioned within the mediastinum. In the standard drainage group, a conventional chest tube (Teleflex Inc.) was used. Other chest tubes were left at the discretion of the operating surgeon.

Results

A total of 520 adult patients undergoing cardiac surgery were randomized to receive either ATC (n = 257) or standard drainage (n = 263). ATC was associated with a 72% reduction in re-exploration for bleeding (5.7% vs 1.6%, p = .01) and an 89% reduction in complete chest tube occlusion (2% vs 19%, p = .01). There was an 18% reduction in POAF between the ATC and control group that was not statistically significant (31% vs 38%, p = .08).

Conclusions and relevance

In this RCT, the implementation of active clearance of chest tubes reduced re-exploration and chest tube clogging in patients after cardiac surgery further supporting recommendations to consider this modality postoperatively.

Trial registration

Clinical Trials NCT02808897. Retrospectively registered 22 June 2016.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13019-021-01414-0.

Postoperative Atrial Fibrillation After Cardiac Surgery: A Meta-Analysis

BACKGROUND

Postoperative atrial fibrillation (POAF) is common after cardiac surgery and linked to poorer short-term and long-term outcomes; however, conflicting evidence exists on stroke risk and how the index procedure affects outcomes. This study aims to provide a comprehensive review of the published outcomes of POAF after cardiac surgery, examined as a whole and by index procedure.

METHODS

A systematic review of POAF after cardiac surgery was conducted. Outcomes related to POAF were analyzed in a meta-analysis, and aggregate survival data were derived to examine long-term survival.

RESULTS

Sixty-one studies with 239,018 patients were identified, the majority (78.7%) undergoing coronary surgery. POAF occurred in 25.5% of patients and was associated with significantly higher rates of early mortality and stroke (odds ratio [OR], 1.74; P < .001; and OR, 2.21, P < .001, respectively) along with longer intensive care and overall hospital length of stay (mean difference 0.8 days, P = .008; and mean difference 2.8 days, P < .001, respectively). After a median of 6.6 years (range, 0.5-20 years), mortality and stroke remained significantly higher for those with POAF (OR, 1.57, P < .001; and OR, 1.81, P = .001). Pooled hazard ratio for long-term mortality was significantly higher for patients who underwent coronary surgery compared with isolated valve surgery.

CONCLUSIONS

POAF is common after cardiac surgery and is associated with significantly higher rates of both short-term and long-term stroke and mortality as well as increased hospital stay. Differences in hazard for long-term survival may be due to the underlying pathophysiological risk factors for POAF, which differ by surgical procedure.

Temporal Dispersion of Atrial Activation Causes Postoperative Atrial Fibrillation

BACKGROUND

Spatial dispersion of atrial activation is a cause of postoperative atrial fibrillation (PoAF) after cardiac surgery. This study evaluated whether temporal dispersion of atrial activation causes PoAF after surgery in a clinical setting.

METHODS

Nineteen patients were enrolled. Postoperative atrial activation was evaluated by 24-hour Holter electrocardiography, with atrial pacing wires on the right atrium, for 5 days after cardiac surgery. No patient received antiarrhythmic drugs, including beta-blockers. The cycle length of 15 continuous atrial beats was measured at 4 time points: (i) earlier than 12 hours before PoAF, as a control, (ii) just before PoAF onset, (iii) during PoAF, and (iv) just before cessation of PoAF. Inhomogeneity of atrial activation was quantified by using the variation coefficient for a cycle length of 15 atrial beats during each phase.

RESULTS

The median inhomogeneity index of atrial activation (interquartile range) was 0.102 (0.046-0.136) in controls, 0.943 (0.582-1.610) just before PoAF onset (vs. control; p=0.009), 0.966 (0.631-1.117) during PoAF, and 0.471 (0.138-0.645) just before cessation of PoAF.

CONCLUSIONS

Dispersion of atrial activation significantly increased just before PoAF onset. Temporal dispersion of atrial activation is a precursory variation of PoAF.

Active chest tube clearance after aortic valve surgery did not influence amount residual pericardial fluid after aortic valve replacement in a randomised trial

Objective. Evaluate if the use of active clearance of chest tubes after aortic valve surgery influenced bleeding and reduced postoperative residual pericardial effusion. Design. Prospective randomised trial comparing PleuraFlow^® 32 F chest tube with FlowGlide™ active clearance to a standard Argyle^® 32 F chest tube in 100 patients undergoing aortic valve surgery. Chest tube outputs and pericardial effusion measurements assessed by two-dimensional transthoracic echocardiography were recorded before hospital discharge. Results. Postoperative chest tube outputs per hour did not differ between the two groups. The median chest tube output was 400 mL for patients who had a PleuraFlow^® chest tube vs. 490 mL for patients with an Argyle^® chest tube (p = .08). Pericardial effusions ≥ 2 mm were detected in 76% vs. 68% of the patients (p = .50) and postoperative atrial fibrillation occurred in 42% vs. 34% (p = .54), respectively. Conclusions. Use of active clearance chest tubes, compared to standard chest tubes after aortic valve surgery did not differ significantly regarding postoperative bleeding or degree of pericardial effusion as measured by echocardiography prior to hospital discharge.

Reduction of drainage-associated complications in cardiac surgery with a digital drainage system: a randomized controlled trial

Background

Thoracic chest drains are placed after cardiac surgery allowing for the clearance of blood, fluid, and air to prevent post-operative complications. Despite its importance, there is little data on the application of digital chest drainage systems in cardiac surgery. Therefore, the differences between an analog and a digital chest drainage system in cardiac surgery patients were investigated in a randomized controlled trial.

Methods

A total of 354 elective cardiac surgery patients were preoperatively randomized 1:1 between September 2016 and September 2017 to either an analog (Ocean) or a digital (Thopaz⁺) chest drainage system aiming to compare drainage-associated postoperative outcome parameters.

Results

A total of 340 patients were included in the analysis (analog: 188; digital: 152) with no significant differences in preoperative baseline parameters. Incidence of X-rays to detect air leaks was significantly lower in the digital group (analog: 20.2%; digital: 8.6%; P<0.01). Patients treated with the digital system showed a 3.3% reduction of re-thoracotomies, however, not statistically significant (analog: 5.3%; digital: 2.0%; P=0.19). Median total fluid amount did not significantly differ between study groups [median (P25; P75); analog: 705 (400; 1,333) mL; digital: 686 (404; 1,229) mL; P=0.83]; however, the use of the digital drainage system resulted in a quicker removal with a reduced median drainage duration of 16 hours (analog: 65 hours; digital: 49 hours; P≤0.01).

Conclusions

The study provides evidence that digital drainage systems can be safely applied in cardiac surgery patients. The use of the digital management system led to a decreased incidence of drainage-associated complications as well as to shortened chest tube duration. Findings require confirmation by additional studies.

Active clearance of chest tubes is associated with reduced postoperative complications and costs after cardiac surgery: a propensity matched analysis

BACKGROUND

Chest tubes are routinely used to evacuate shed mediastinal blood in the critical care setting in the early hours after heart surgery. Inadequate evacuation of shed mediastinal blood due to chest tube clogging may result in retained blood around the heart and lungs after cardiac surgery. The objective of this study was to compare if active chest tube clearance reduces the incidence of retained blood complications and associated hospital resource utilization after cardiac surgery.

METHODS

Propensity matched analysis of 697 consecutive patients who underwent cardiac surgery at a single center. 302 patients served as a baseline control (Phase 0), 58 patients in a training and compliance verification period (Phase 1) and 337 were treated prospectively using active tube clearance (Phase 2). The need to drain retained blood, pleural effusions, postoperative atrial fibrillation, ICU resource utilization and hospital costs were assessed.

RESULTS

Propensity matched patients in Phase 2 had a reduced need for drainage procedures for pleural effusions (22% vs. 8.1%, p < 0.001) and reduced postoperative atrial fibrillation (37 to 25%, P = 0.011). This corresponded with fewer hours in the ICU (43.5 [24-79] vs 30 [24-49], p = < 0.001), reduced median postoperative length of stay (6 [4-8] vs 5 [4-6.25], p < 0.001) median costs reduced by $1831.45 (- 3580.52;82.38, p = 0.04) and the mean costs reduced by an average of $2696 (- 6027.59;880.93, 0.116).

CONCLUSIONS

This evidence supports the concept that efforts to actively maintain chest tube patency in early recovery is useful in improving outcomes and reducing resource utilization and costs after cardiac surgery.

TRIAL REGISTRATION

Clinicaltrial.gov, NCT02145858, Registered: May 23, 2014.

Pericardial closure with extracellular matrix scaffold following cardiac surgery associated with a reduction of postoperative complications and 30-day hospital readmissions

BACKGROUND

A prospective, multi-center study (RECON) was conducted to evaluate the clinical outcomes of pericardial closure using a decellularized extracellular matrix (ECM) graft derived from porcine small intestinal submucosa.

METHODS

Patients indicated for open cardiac surgery with pericardial closure using ECM were eligible for the RECON study cohort. Postoperative complications and readmission of the RECON patients were compared to the patient cohort in the Nationwide Readmissions Database (NRD). Inverse probability of treatment weighting was used to control the differences in patient demographics, comorbidities, and risk factors.

RESULTS

A total of 1420 patients at 42 centers were enrolled, including 923 coronary artery bypass grafting (CABG) surgeries and 436 valve surgeries. Significantly fewer valve surgery patients in the RECON cohort experienced pleural effusion (3.1% vs. 13.0%; p < 0.05) and pericardial effusion (1.5% vs. 2.6%; p < 0.05) than in the NRD cohort. CABG patients in the RECON cohort were less likely to suffer bleeding (1.2% vs. 2.9%; p < 0.05) and pericardial effusion (0.2% vs. 2.2%, p < 0.05) than those in the NRD cohort. The 30-day all-cause hospital readmission rate was significantly lower among RECON patients than NRD patients following both valve surgery (HR: 0.34; p < 0.05) and CABG surgery (HR: 0.42; p < 0.05). In the RECON study, 14.4% of CABG patients and 27.0% of valve patients had postoperative atrial fibrillation as compared to previously reported risks, which generally ranges from 20 to 30% after CABG and from 35 to 50% after valve surgery.

CONCLUSIONS

Pericardial closure with ECM following cardiac surgery is associated with a reduction in the proportion of patients with pleural effusion, pericardial effusion, and 30-day readmission compared to a nationwide database.

TRIAL REGISTRATION

NCT02073331 , Registered on February 27, 2014.