Direct oral anticoagulants for atrial fibrillation in early postoperative valve repair or bioprosthetic replacement

OBJECTIVE

Despite increased use of direct oral anticoagulants (DOACs), limited evidence guides their use in the early postoperative period after bioprosthetic valve implantation in patients with atrial fibrillation. Our objective was to describe the efficacy and safety of DOACs and warfarin in the first 3 months after surgical bioprosthetic valve replacement or repair in patients with atrial fibrillation.

METHODS

This was a retrospective, registry-informed cohort study of surgical patients who underwent bioprosthetic valve replacement or repair, had concomitant atrial fibrillation and received oral anticoagulation at discharge. The primary efficacy outcome was a composite of death, ischemic stroke, transient ischemic attack, and systemic embolism; the primary safety outcome was a composite of major bleeding. Key secondary outcomes were comparative analyses of primary outcomes, temporal anticoagulation prescribing patterns, and 30-day readmission rates.

RESULTS

A total of 1743 patients were included. Of the 570 patients in the DOAC group, 17 (2%) met the composite efficacy outcome and 55 (10%) met the composite safety outcome. Of the 1173 patients receiving warfarin, 41 (3%) and 114 (10%) met the composite efficacy and safety outcomes, respectively. Comparative secondary analysis was not statistically significant for either the efficacy (adjusted odds ratio, 0.85; 95% confidence interval, 0.46-1.55, P = .59) or safety (adjusted odds ratio, 0.94; 95% confidence interval, 0.66-1.34, P = .76) outcomes. The 30-day readmission rates were similar between both groups.

CONCLUSIONS

Our results suggest DOACs may be safe and effective alternatives to warfarin in the early postoperative period after valve repair or surgical bioprosthetic replacement. Confirmation awaits adequately powered prospective studies.

Lesion durability found during mandated percutaneous catheter ablation after surgical cryo-ablation for treatment of non-paroxysmal atrial fibrillation

OBJECTIVES

Current recommendations support surgical treatment of atrial fibrillation (AF) in patients indicated for cardiac surgery. These procedures are referred to as concomitant and may be carried out using radiofrequency energy or cryo-ablation. This study aimed to assess the electrophysiological findings in patients undergoing concomitant cryo-ablation.

METHODS

Patients with non-paroxysmal AF undergoing coronary artery bypass grafting and/or valve repair/replacement were included in the trial if concomitant cryo-ablation was part of the treatment plan according to current guidelines. The patients reported in this study were assigned to undergo staged percutaneous radiofrequency catheter ablation (PRFCA), i.e., hybrid treatment, as a part of the SURHYB trial protocol.

RESULTS

We analyzed 103 patients who underwent PRFCA 105 ± 35 days after surgery. Left and right pulmonary veins (PVs) were found isolated in 65 (63.1%) and 63 (61.2%) patients, respectively. The LA posterior wall isolation and mitral isthmus conduction block were found in 38 (36.9%) and 18 (20.0%) patients, respectively. Electrical reconnections (gaps) in the left PVs were more often localized superiorly than inferiorly (57.9% vs. 26.3%, P = 0.005) and anteriorly than posteriorly (65.8% vs. 31.6%, P = 0.003). Gaps in the right PVs were more equally distributed anteroposteriorly but dominated in superior segments (72.5% vs. 40.0%, P = 0.003). There was a higher number of gaps on the roof line compared to the inferior line (131 (67.2%) vs. 67 (42.2%), P < 0.001). Compared to epicardial cryo-ablation, endocardial was more effective in creating PVs and LA posterior wall isolation (P < 0.05). Cryo-ablation using nitrous oxide (N20) or argon (Ar) gas as cooling agents was similarly effective (P = NS).

CONCLUSIONS

The effectiveness of surgical cryo-ablation in achieving transmural and durable lesions in the left atrium is surprisingly low. Gaps are located predominantly in the superior and anterior portions of the PVs and on the roof line. Endocardial cryo-ablation is more effective than epicardial ablation, irrespective of the cooling agent used.

Surgical Coronary Revascularization in Patients With Underlying Atrial Fibrillation: State-of-the-Art Review

The number of individuals referred for coronary artery bypass grafting (CABG) with preoperative atrial fibrillation (AF) is reported to be 8% to 20%. Atrial fibrillation is a known marker of high-risk patients as it was repeatedly found to negatively influence survival. Therefore, when performing surgical revascularization, consideration should be given to the concomitant treatment of the arrhythmia, the clinical consequences of the arrhythmia itself, and the selection of adequate surgical techniques. This state-of-the-art review aimed to provide a comprehensive analysis of the current understanding of, advancements in, and optimal strategies for CABG in patients with underlying AF. The following topics are considered: stroke prevention, prophylaxis and occurrence of postoperative AF, the role of surgical ablation and left atrial appendage occlusion, and an on-pump vs off-pump strategy. Multiple acute complications can occur in patients with preexisting AF undergoing CABG, each of which can have a significant effect on patient outcomes. Long-term results in these patients and the future perspectives of this scientific area were also addressed. Preoperative arrhythmia should always be considered for surgical ablation because such an approach improves prognosis without increasing perioperative risk. While planning a revascularization strategy, it should be noted that although off-pump coronary artery bypass provides better short-term outcomes, conventional on-pump approach may be beneficial at long-term follow-up. By collecting the current evidence, addressing knowledge gaps, and offering practical recommendations, this state-of-the-art review serves as a valuable resource for clinicians involved in the management of patients with AF undergoing CABG, ultimately contributing to improved outcomes and enhanced patient care.

Sequential hybrid ablation vs. surgical CryoMaze alone for treatment of atrial fibrillation: results of multicentre randomized controlled trial

AIMS

Data on the hybrid atrial fibrillation (AF) treatment are lacking in patients with structural heart disease undergoing concomitant CryoMaze procedures. The aim was to assess whether the timely pre-emptive catheter ablation would achieve higher freedom from AF or atrial tachycardia (AT) and be associated with better clinical outcomes than surgical ablation alone.

METHODS AND RESULTS

The trial investigated patients with non-paroxysmal AF undergoing coronary artery bypass grafting and/or valve repair/replacement with mandatory concomitant CryoMaze procedure who were randomly assigned to undergo either radiofrequency catheter ablation [Hybrid Group (HG)] or no further treatment (Surgery Group). The primary efficacy endpoint was the first recurrence of AF/AT without class I or III antiarrhythmic drugs as assessed by implantable cardiac monitors. The primary clinical endpoint was a composite of hospitalization for arrhythmia recurrence, worsening of heart failure, cardioembolic event, or major bleeding. We analysed 113 and 116 patients in the Hybrid and Surgery Groups, respectively, with a median follow-up of 715 (IQR: 528-1072) days. The primary efficacy endpoint was significantly reduced in the HG [41.1% vs. 67.4%, hazard ratio (HR) = 0.38, 95% confidence interval (CI): 0.26-0.57, P < 0.001] as well as the primary clinical endpoint (19.9% vs. 40.1%, HR = 0.51, 95% CI: 0.29-0.86, P = 0.012). The trial groups did not differ in all-cause mortality (10.6% vs. 8.6%, HR = 1.17, 95%CI: 0.51-2.71, P = 0.71). The major complications of catheter ablation were infrequent (1.9%).

CONCLUSION

Pre-emptively performed catheter ablation after the CryoMaze procedure was safe and associated with higher freedom from AF/AT and improved clinical outcomes.

Sequential hybrid ablation versus surgical CryoMaze alone for treatment of atrial fibrillation (SurHyb Trial): a protocol of the multicentre randomized controlled trial

BACKGROUND

Atrial fibrillation is common in patients with structural heart disease who are undergoing cardiac surgery. Surgical CryoMaze has been shown to be an effective treatment in several trials, but success rates have varied considerably, between 47-95%. The sequential hybrid approach, combining surgical CryoMaze followed by radiofrequency catheter ablation, can achieve high freedom from atrial arrhythmias. However, in patients with concomitant surgical atrial fibrillation treatment, data comparing the hybrid approach to CryoMaze alone are lacking.

METHODS

The SurHyb study was designed as a prospective, open-label, multicentre randomized trial. Patients with non-paroxysmal atrial fibrillation who were scheduled for coronary artery bypass grafting or valve repair/replacement were randomized to either surgical CryoMaze alone or surgical CryoMaze followed by radiofrequency catheter ablation 3 months post-surgery. The primary outcome measure was arrhythmia-free survival without class I or III antiarrhythmic drugs, which has been evaluated using implantable cardiac monitors.

CONCLUSIONS

This is the first randomized study that compares concomitant surgical CryoMaze alone with the staged hybrid surgical CryoMaze followed by catheter ablation, in patients with non-paroxysmal atrial fibrillation using rigorous rhythm monitoring. The results may contribute to the optimization of the treatment in patients undergoing concomitant CryoMaze for atrial fibrillation.

Mid‐term outcomes of concomitant Cox‐Maze IV: Results from a multicenter prospective registry

Background

Benefits of concomitant atrial fibrillation (AF) surgical treatment are well established. Cardiac societies support treating AF during cardiac surgery with a class I recommendation. Despite these guidelines, adoption has been inconsistent. We report results of routine performance of concomitant Cox‐Maze IV (CMIV) from participating centers using a standardized, prospective registry.

Methods

Nine surgeons at four cardiac surgery programs enrolled 807 patients undergoing concomitant CMIV surgery over 12 years. Lesions were created using bipolar radiofrequency clamps and cryoablation probes. Follow‐up occurred at 3‐ and 6‐months, then annually for 3 years. Freedom from AF was defined as no episode >30 s of atrial arrhythmia.

Results

Sixty‐four percent of patients were male, mean age 69 years, mean left atrial size 4.6 cm, mean preoperative AF duration 4.0 years, mean EuroSCORE 6.4, and mean CHADS₂ score 3.1. Thirty‐day postoperative mortality and neurologic event rates were 3.3% and 1.3%, respectively. New pacemaker implant rate was 6.3%. Freedom from AF rates at 1‐ and 3‐years stratified by preoperative AF type were: paroxysmal 94.6% and 87.5%, persistent 82.1% and 81.9%, and longstanding persistent 84.1% and 78.1%. At 3‐year follow up, 84% of patients were off antiarrhythmic drugs and 74% of sinus rhythm patients were off oral anticoagulants.

Conclusions

Routine CMIV is safe and effective. Acceptable outcomes can be achieved across multiple centers and multiple operators even in a moderate risk patient population undergoing more complex procedures. Surgeons and institutions should be encouraged by all cardiac societies to adopt the CMIV procedure to maximize patient benefit.

Patients with Atrial Fibrillation Benefit from SAVR with Surgical Ablation Compared to TAVR Alone

Introduction

In patients with preoperative atrial fibrillation (AF) undergoing aortic valve replacement, the addition of surgical ablation to surgical aortic valve replacement (SAVR-SA) is efficacious and a Class I guideline. We hypothesized that this subgroup may benefit from SAVR-SA compared to transcatheter aortic valve replacement (TAVR) alone.

Methods

Medicare beneficiaries with persistent non-valvular AF who underwent SAVR-SA or TAVR alone between 2012 and 2018 were included. Patients with high-risk surgical comorbidities were excluded. Groups were matched using inverse probability weighting. The primary outcome was all-cause mortality. Secondary outcomes were stroke, transient ischemic attack, permanent pacemaker implantation, bleeding, rehospitalization for atrial arrhythmias, and rehospitalization for heart failure. Kaplan–Meier estimates and Cox proportional-hazards regression were used to compare outcomes. Outcomes were adjusted for variables with a standardized mean difference greater than 0.1.

Results

Of 439,492 patients who underwent aortic valve replacement, 2591 underwent SAVR-SA and 1494 underwent TAVR alone. Weighting resulted in adequately matched groups. Compared to TAVR alone, SAVR-SA was associated with a significant reduction in all-cause mortality (HR 0.65, 95% CI 0.53–0.79), permanent pacemaker implantation (HR 0.62, 95% CI 0.44–0.87), bleeding (HR 0.63, 95% CI 0.39–1.00), and rehospitalization for heart failure (HR 0.49 (0.36–0.65). There was no difference in the incidence of stroke (HR 1.07, 95% CI 0.74–1.54), transient ischemic attack (HR 1.05, 95% CI 0.75–1.47), or rehospitalization for atrial arrhythmia.

Conclusion

Select patients with persistent non-valvular AF may benefit from SAVR-SA compared to TAVR alone.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40119-022-00262-w.

Red Blood Cell Distribution Width Predicts Myocardial Infarction and Mortality After Vascular Surgery-A Prospective Cohort Study

BACKGROUND

This study aims to investigate the association between preoperative Red blood cell Distribution Width (RDW) and postoperative outcomes, including myocardial infarction (MI), and mortality.

METHODS

A prospective cohort including all patients submitted to elective vascular arterial surgery at a university hospital. The primary and secondary outcomes were 30-day mortality and 30-day MI, respectively.

RESULTS

Atrial fibrillation, chronic kidney disease (CKD), and dependent functional status were more prevalent in deceased patients. After multivariable analysis, age (adjusted OR 1.08, 95% Confidence Interval [1.01-1.15], p = 0.027) and RDW-standard deviation (RDW-SD) (1.08 [1.01-1.16], p = 0.032) remained independent predictors of mortality. Patients with MI had higher rates of diabetes, CKD, dependent functional status, ASA physical status IV, and insulin medication. After multivariable analysis, dependent functional status (4.8 [1.6-15.0], p = 0.007), insulin medication (4.4 [1.5-12.6], p = 0.007) and RDW-SD (1.10 [1.02-1.19], p = 0.020) were independent predictors of MI.

CONCLUSION

RDW-SD independently predicted postoperative MI and mortality, and may provide valuable information for prevention and early management of adverse outcomes.

Inclusion of interleukin-6 improved performance of postoperative delirium prediction for patients undergoing coronary artery bypass graft (POD-CABG): A derivation and validation study

BACKGROUND

Patients undergoing coronary artery bypass graft (CABG) are at high risk for developing postoperative delirium (POD). A simple prediction rule may benefit patients from early identification of POD followed by adequate preventive strategies. The purpose of the current study was to develop and validate a POD prediction rule for patients undergoing CABG (POD-CABG), by considering all possible perioperative factors.

METHODS

In this prospective cohort study, patients who underwent first elective isolated CABG were continuously enrolled from May 2014 to November 2015 in a tertiary hospital. Delirium was assessed using the Confusion Assessment Method for Intensive Care Unit. Patients' perioperative risk factors were collected through interviews and review of medical records. The area under receiver-operating characteristic curve (AUC) was used to assess the overall performance of the predictive rule.

RESULTS

A total of 242 and 148 patients were enrolled in the derivation and validation cohorts, respectively. Multiple logistic regression analysis identified seven variables that were independently associated with POD: age (≥65 years), gender (female), history of myocardial infarction and diabetes mellitus, postoperative atrial fibrillation, the use of intra-aortic balloon pump, and serum interleukin-6 ≥478 pg/ml at 18 hours after surgery. The AUC of the POD-CABG was 0.84 (95% CI, 0.79-0.90) in the derivation cohort, and was 0.86 (95% CI, 0.80-0.91) after bootstrap resampling. The AUC was 0.81 (95% CI, 0.73-0.88) after the POD-CABG was applied to the validation cohort.

CONCLUSIONS

The POD-CABG with inclusion of interleukin-6 demonstrated good performance in predicting POD.

Levothyroxine Treatment and the Risk of Cardiac Arrhythmias - Focus on the Patient Submitted to Thyroid Surgery

Levothyroxine (LT4) is used to treat frequently encountered endocrinopathies such as thyroid diseases. It is regularly used in clinical (overt) hypothyroidism cases and subclinical (latent) hypothyroidism cases in the last decade. Suppressive LT4 therapy is also part of the medical regimen used to manage thyroid malignancies after a thyroidectomy. LT4 treatment possesses dual effects: substituting new-onset thyroid hormone deficiency and suppressing the local and distant malignancy spreading in cancer. It is the practice to administer LT4 in less-than-high suppressive doses for growth control of thyroid nodules and goiter, even in patients with preserved thyroid function. Despite its approved safety for clinical use, LT4 can sometimes induce side-effects, more often recorded with patients under treatment with LT4 suppressive doses than in unintentionally LT4-overdosed patients. Cardiac arrhythmias and the deterioration of osteoporosis are the most frequently documented side-effects of LT4 therapy. It also lowers the threshold for the onset or aggravation of cardiac arrhythmias for patients with pre-existing heart diseases. To improve the quality of life in LT4-substituted patients, clinicians often prescribe higher doses of LT4 to reach low normal TSH levels to achieve cellular euthyroidism. In such circumstances, the risk of cardiac arrhythmias, particularly atrial fibrillation, increases, and the combined use of LT4 and triiodothyronine further complicates such risk. This review summarizes the relevant available data related to LT4 suppressive treatment and the associated risk of cardiac arrhythmia.

Incidence, Risk Factors and Impact on Long-Term Outcome of Postoperative Delirium After Transcatheter Aortic Valve Replacement

Background: The aim of the present study was to analyze incidence, risk factors, and association with long-term outcome of postoperative delirium (POD) after transcatheter aortic valve replacement (TAVR).

Methods: Six hundred and sixty one consecutive patients undergoing TAVR were prospectively enrolled from January 2016 to December 2017. POD was assessed regularly during ICU-stay using the CAM-ICU test.

Results: The incidence of POD was 10.0% (n = 66). Patients developing POD were predominantly male (65%), had higher EuroSCORE II (5.4% vs. 3.9%; P = 0.041) and were more often considered frail (70% vs. 26%; P < 0.001). POD was associated with more peri-procedural complications including vascular complications (19.7 vs. 9.4; P = 0.017), bleeding (12.1 vs. 5.4%; P = 0.0495); stroke (4.5 vs. 0.7%; P = 0.025), respiratory failure requiring ventilation (16.7% vs. 1.8%; P < 0.001), and pneumonia (34.8% vs. 7.1%; P < 0.001). Consequently, patients with POD had significantly longer ICU- (7.9 vs. 3.2 days P < 0.001) and hospital-stay (14.9 vs. 9.0 days; P < 0.001), and higher in-hospital mortality (6.1 vs. 2.1%; P = 0.017). Logistic regression analysis identified male sex (odds ratio (OR) 2.2 [95% confidence interval (CI) 1.2–4.0); P = 0.012], atrial fibrillation [OR 3.0 (CI 1.6–5.6); P < 0.001], frailty [OR 4.3 (CI 2.4–7.9); P < 0.001], pneumonia [OR 4.4 (CI 2.3–8.7); P < 0.001], stroke [OR 7.0 (CI 1.2–41.6); P = 0.031], vascular complication [OR 2.9 (CI 1.3–6.3); P = 0.007], and general anesthesia [OR 2.0 (CI 1.0–3.7); P = 0.039] as independent predictors of POD. On Cox proportional hazard analysis POD emerged as a significant predictor of 2-year mortality [HR 1.89 (CI 1.06–3.36); P = 0.030].

Conclusion: POD is a frequent finding after TAVR and is significantly associated with reduced 2-year survival. Predictors of delirium include not only peri-procedural parameters like stroke, pneumonia, vascular complications and general anesthesia but also baseline characteristics as male sex, atrial fibrillation and frailty.

Partial upper sternotomy for concomitant left atrial ablation and aortic valve replacement

BACKGROUND

Minimally invasive access via partial sternotomy has been established for aortic valve surgery in the past years. But concomitant procedures like atrial ablation and aortic valve replacement via partial upper sternotomy have not been investigated so far. We therefore present our operative technique and results in terms of safety and efficacy, including follow-up and quality of life.

METHODS

Between February 2007 and March 2014 a total of 67 patients undergoing isolated minimally invasive aortic valve replacement received concomitant left atrial ablation at our centre. Operative technique and short- and midterm results are described, including quality of life assessment using the SF-36 questionnaire.

RESULTS

Operative techniqual success rate was 98.5%. We observed only one (1.5%) ablation-related conversion to full sternotomy. Operative times, reexploration and stroke rates as well as 30-day mortality are comparable to open procedures. Efficacy: The proportions of patients in sinus rhythm at discharge was 54.5% for paroxysmal AF patients and 27.7% overall. After a mean follow-up time of 38.0±22.6 months the cardiac related mortality rate was 4.5%, the rate of sinus rhythm was 72.7% for paroxysmal AF patients and 36.8% overall. Of survivors, overall mean quality of life was 7.3±2.1 as measured by SF-36.

CONCLUSIONS

Concomitant left atrial ablation and aortic valve replacement can safely be performed via partial sternotomy and results are non-inferior to open surgery.

Risk of Recurrent Bleeding Events in Nonvalvular Atrial Fibrillation Treated with Vitamin K Antagonists: A Clinical Practice Research Datalink Study

Background  There is little evidence on how the occurrence of a bleed in individuals on vitamin K antagonists (VKAs) impacts the risk of subsequent bleeds, and thromboembolic and ischemic events. Such information would help to inform treatment decisions following bleeds.

Objective  To estimate the impact of bleeding events on the risk of subsequent bleeds, venous thromboembolism (VTE), stroke, and myocardial infarction (MI) among patients initiating VKA treatment for new-onset nonvalvular atrial fibrillation (NVAF).

Methods  We conducted an observational cohort study using a linked Clinical Practice Research Datalink—Hospital Episode Statistics dataset. Among a cohort of individuals with NVAF, the risk of clinically relevant bleeding, VTE, stroke, and MI was compared between the period prior to the first bleed and the periods following each subsequent bleed. The rate and cost of general practitioner (GP) consultations, prescriptions, and hospitalizations were also compared across these periods.

Results  The risk of clinically relevant bleeding events was observed to be elevated at least twofold in all periods following the first bleeding event. The risk of VTE, stroke, and MI was not found to differ according to the number of clinically relevant bleeding events. The rate and cost of GP consultations, GP prescriptions, and hospitalizations were increased in all periods relative to the period prior to the first bleed.

Conclusions  The doubling in the risk of bleeding following the first bleed, taken alongside the stable risk of MI, VTE, and stroke, suggests that the risk–benefit balance for VKA treatment should be reconsidered following the first clinically relevant bleed.

Current Readings: An Update on Prevention and Management of Atrial Fibrillation Post Cardiac Surgery

Atrial fibrillation (afib) remains the most common complication following cardiac surgery and is associated with increased mortality and resource utilization. As increasing number of patients with multiple comorbidities undergo cardiac surgery, and, given the overall burden of afib in the perioperative setting, there is growing interest among clinicians to improve diagnosis and management of afib among cardiac surgery patients. Advances in technology, refinements in surgical techniques, and innovations in drug development also contributed to this changing landscape. Despite the promising results of recently published studies on afib management following cardiac surgery, afib remains a complex problem with various presentations. Although myriad medical and surgical therapies for high-risk patients exist, determining patient-specific optimal treatment can be difficult. Understanding the context and relevance of contemporary studies is therefore critical to ensure appropriate patient selection and reduction of overall morbidity and mortality. This review closely examines 5 timely articles that delineate the most important results in the management of afib after cardiac surgery in the current era.

Sequential Hybrid CryoMaze Ablation versus Surgical CryoMaze Alone for the Treatment of Atrial Fibrillation (SurHyb): study protocol for a randomized controlled trial

Background

Atrial fibrillation is common in patients with structural heart disease who are undergoing cardiac surgery. Surgical CryoMaze has been shown to be an effective treatment in several trials, but success rates have varied considerably, between 47–95 %. The sequential hybrid approach, combining surgical CryoMaze followed by radiofrequency catheter ablation, can achieve high freedom from atrial arrhythmias, even when rigorous methods to detect arrhythmias after the procedure are used. However, data from randomized trials comparing hybrid ablations to surgical ablations alone are lacking.

Methods/Design

The SurHyb study is a prospective, multicenter, randomized study. Patients with persistent or long-standing persistent atrial fibrillation will be randomized to either surgical CryoMaze alone or surgical CryoMaze followed by catheter ablation 3 months post-surgery. The primary outcome measure is arrhythmia-free survival without class I or III antiarrhythmic drugs, which will be evaluated using 7-day ECG Holter monitoring at 24 months. A total of 260 patients will be investigated from three medical centers in the Czech Republic to obtain the relevant information.

Discussion

This is the first randomized study that compares surgical CryoMaze alone with the staged hybrid surgical CryoMaze followed by catheter ablation in patients with persistent or long-standing persistent atrial fibrillation. These results will contribute to the optimization of the treatment for these patients.

Trial registration

Czech Clinical Trials Registry, cz-301020151253. Registered on 30 October 2015.

Incidence of late atrial fibrillation in bilateral lung versus heart transplants

BACKGROUND

We compared the incidence of late-onset atrial fibrillation in orthotopic heart transplant recipients and bilateral orthotopic lung transplant recipients.

METHODS

We reviewed the records of all heart and lung transplant operations carried out in our institution between 1995 and 2015. We performed 1:1 propensity-matching based on patient age, sex, body mass index, and hypertension. Our primary outcome, late-onset atrial fibrillation, was defined as atrial fibrillation occurring after discharge following hospitalization for transplantation.

RESULTS

Over the study period, 397 orthotopic heart transplants and 240 bilateral orthotopic lung transplants were performed. Propensity matching resulted in 173 pairs who were matched with respect to age, sex, body mass index, and preoperative hypertension. The median follow-up was 5.3 years for heart transplant patients and 3.1 years for lung transplant patients. Late-onset atrial fibrillation occurred in 11 heart transplant patients (5 of whom had biopsy-proven evidence of rejection) and 19 lung transplant patients (2 of whom had biopsy-proven evidence of rejection). On Kaplan-Meier analysis, the probability of late-onset atrial fibrillation at 5 years was 4.3% for heart transplant patients vs. 13.9% for lung transplant patients (log-rank p = 0.01).

CONCLUSIONS

We documented an increased probability of late-onset atrial fibrillation among bilateral orthotopic lung transplant patients compared to orthotopic heart transplant patients. This was a hypothesis-generating study that suggests a potential role for cardiac autonomic innervation in the genesis of atrial fibrillation.

Effectiveness of Surgical Ablation in Patients With Atrial Fibrillation and Aortic Valve Disease

BACKGROUND

In patients with atrial fibrillation (AF), the addition of surgical ablation to aortic valve replacement (AVR) does not increase procedural morbidity or mortality. However, efficacy in this population has not been carefully evaluated. This study compared outcomes between patients undergoing stand-alone Cox-Maze IV with those undergoing surgical ablation and concomitant AVR.

METHODS

From January 2002 to May 2014, 188 patients received a stand-alone Cox-Maze IV (n = 113) or surgical ablation with concomitant AVR (n = 75). In the concomitant AVR group, patients underwent Cox-Maze IV (n = 58), left-sided Cox-Maze IV (n = 3), or pulmonary vein isolation (n = 14). Thirty-one perioperative variables were compared. Freedoms from AF on and off antiarrhythmic drugs were evaluated at 3, 6, 12, and 24 months.

RESULTS

Follow-up was available in 97% of patients. Freedom from AF on and off antiarrhythmic drugs in patients receiving a stand-alone Cox-Maze IV versus concomitant AVR was not significantly different at any time point. The concomitant AVR group had more comorbidities, paroxysmal AF, pacemaker implantations (24% vs 5%, p = 0.002), and complications (25% vs 5%, p < 0.001). Freedoms from AF off antiarrhythmic drugs for patients receiving an AVR and pulmonary vein isolation at 1 year was only 50%, which was significantly lower than patients receiving an AVR and Cox-Maze IV ( 94%, p = 0.001).

CONCLUSIONS

A Cox-Maze IV with concomitant AVR is as effective as a stand-alone Cox-Maze IV in treating AF, even in an older population with more comorbidities. Pulmonary vein isolation was not as effective and is not recommended in this population. A Cox-Maze IV should be considered in all patients undergoing AVR with a history of AF.

Effect of Surgical Atrial Fibrillation Ablation at the Time of Cardiac Surgery on Risk of Postoperative Pacemaker Implantation

The aim of this study was to retrospectively investigate whether performing surgical atrial fibrillation (AF) ablation in conjunction with cardiac surgery (CS) increases the risk for postoperative permanent pacemaker (PPM) requirement. The 30-day risk for PPM requirement was analyzed in consecutive patients who underwent CS from January 2007 to August 27, 2013. Patients were divided into 3 groups: (1) those who underwent AF ablation concomitant with CS (AF ABL), (2) patients with any history of AF who underwent surgery who did not undergo ablation (AF NO ABL), and (3) those with no histories of AF who underwent surgery (NO AF). Logistic regression analysis was performed adjusting for age, gender, and surgery type. Of 13,453 CS patients, 353 (3%) were in the AF ABL group, 1,701 (12%) in the AF NO ABL group, and 11,399 (85%) in the NO AF group. A total of 7,651 patients (57%) underwent coronary artery bypass grafting, 4,384 (33%) underwent valve surgery, and 1,418 (10%) underwent coronary artery bypass grafting and valve surgery. The overall PPM risk was 1.6% (212 of 13,453); risk was 5.7% (20 of 353) in the AF ABL group, 3.1% (53 of 1,701) in the AF NO ABL group, and 1.2% (139 of 11,399) in the NO AF group. The unadjusted and adjusted odds of PPM were higher in the AF ABL and AF NO ABL groups than in the NO AF group (adjusted odds ratio [OR] 2.7, 95% confidence interval [CI] 1.7 to 4.4, and adjusted OR 1.7, 95% CI 1.2 to 2.4, respectively). The unadjusted OR comparing the AF ABL group and the AF NO ABL group was significant (unadjusted OR 1.9, 95% CI 1.9 to 3.2); however, the OR adjusted for surgery type, age, and gender showed a trend toward significance (adjusted OR 1.6, 95% CI 0.9 to 2.7). In conclusion, in this large cohort of patients who underwent CS, surgical AF ablation appeared to carry an increased risk for postoperative PPM implantation.

Bedside tool for predicting the risk of postoperative atrial fibrillation after cardiac surgery: the POAF score

Background

Atrial fibrillation (AF) remains the most common complication after cardiac surgery. The present study aim was to derive an effective bedside tool to predict postoperative AF and its related complications.

Methods and Results

Data of 17 262 patients undergoing adult cardiac surgery were retrieved at 3 European university hospitals. A risk score for postoperative AF (POAF score) was derived and validated. In the overall series, 4561 patients (26.4%) developed postoperative AF. In the derivation cohort age, chronic obstructive pulmonary disease, emergency operation, preoperative intra‐aortic balloon pump, left ventricular ejection fraction <30%, estimated glomerular filtration rate <15 mL/min per m² or dialysis, and any heart valve surgery were independent AF predictors. POAF score was calculated by summing weighting points for each independent AF predictor. According to the prediction model, the incidences of postoperative AF in the derivation cohort were 0, 11.1%; 1, 20.1%; 2, 28.7%; and ≥3, 40.9% (P<0.001), and in the validation cohort they were 0, 13.2%; 1, 19.5%; 2, 29.9%; and ≥3, 42.5% (P<0.001). Patients with a POAF score ≥3, compared with those without arrhythmia, revealed an increased risk of hospital mortality (5.5% versus 3.2%, P=0.001), death after the first postoperative day (5.1% versus 2.6%, P<0.001), cerebrovascular accident (7.8% versus 4.2%, P<0.001), acute kidney injury (15.1% versus 7.1%, P<0.001), renal replacement therapy (3.8% versus 1.4%, P<0.001), and length of hospital stay (mean 13.2 versus 10.2 days, P<0.001).

Conclusions

The POAF score is a simple, accurate bedside tool to predict postoperative AF and its related or accompanying complications.

Evaluation of the prevalence and risk factors of delirium in cardiac surgery ICU

INTRODUCTION

Delirium is defined as an acute cognitive disorder presenting with fluctuation in cognition, apathy and non-organized thinking. It may increase morbidity, mortality, ICU stay and cost. In patients who underwent heart surgery delirium may increase post-operative complications such as respiratory insufficiency, sternum instability and need to re-operation of the sternum. The aim of this study was to evaluate the prevalence and risk factors of delirium in patients admitted to cardiac surgery.

MATERIALS AND METHODS

18 years or older patients who had undergone cardiac surgeries and stayed for more than 24 hours in ICU following surgery were recruited. All subjects were assessed for signs &amp; symptoms of delirium using CAM-ICU and its risk factors. All data were analyzed by SPSS 16 at the end of the study.

RESULTS

The prevalence of delirium in these patients was 23.5% (47 patients). The mean age of patients with delirium was more than other patients (P=0.001). The Incidence of delirium in the patients with cardiopulmonary bypass surgery (CPB) was higher than the patients without CPB (P=0.01). The Incidence of delirium in the patients with Atrial fibrillation was higher than patients without it (P=0.002). The Incidence of delirium in the patients with CVA history was higher than the patients without CVA history (P=0.032). The mean time of mechanical ventilation in the delirious patients was more than other patients (P=0.01).

CONCLUSION

Older Age, CPB, history of CVA, Atrial Fibrillation, and prolonged mechanical ventilation are considered as the risk factors of delirium in cardiac surgery patients.

Ranolazine Enhances the Antiarrhythmic Activity of Amiodarone by Accelerating Conversion of New-Onset Atrial Fibrillation After Cardiac Surgery

Ranolazine is a relatively novel antiischemic/antianginal compound with antiarrhythmic properties. We investigated its ability to shorten the time to conversion of postoperative atrial fibrillation (POAF) when added to amiodarone after coronary artery bypass graft (CABG) surgery. In this prospective, randomized, allocation-concealed, single-blind, single-site clinical trial, we enrolled consecutive eligible patients who developed POAF after elective on-pump CABG surgery. Participants were randomized to receive either ranolazine 375 mg twice daily orally plus intravenous amiodarone (active group) or intravenous amiodarone alone (control group). We enrolled 41 patients; 20 in the active and 21 in the control group. There were no significant differences between the groups in terms of age, procedural duration, extracorporeal circulation time, and aortic cross-clamp time. Mean time of conversion was significantly shorter in the active group (19.9 ± 3.2 vs 37.2 ± 3.9 hours, P < .001), suggesting that compared to amiodarone alone, the ranolazine–amiodarone combination had a superior antiarrhythmic effect against POAF.

Predictors of Prolonged Stay in the Intensive Care Unit following Cardiac Surgery

The prediction of intensive care unit length of stay (ICU-LOS) could contribute to more efficient ICU resources' allocation and better planning of care among cardiac surgery patients. The aim of this study was to identify the preoperative and intraoperative predictors for prolonged cardiac surgery ICU-LOS. An observational cohort study was conducted among 150 consecutive patients, who were admitted to the cardiac surgery ICU of a tertiary hospital of Athens, Greece from September 2010 to January 2011. Multivariate regression analysis revealed that patients with increased creatinine levels preoperatively (odds ratio (OR) 3.0, P = 0.049), history of atrial fibrillation (AF) (OR 6.3, P = 0.012) and high EuroSCORE values (OR 2.6, P = 0.017) had a significant greater probability to stay in the ICU for more than 2 days. In addition, intraoperative hyperglycemia (OR 3.0, P = 0.004) was strongly associated with longer ICU-LOS. In conclusion, the high perioperative risk, the history of AF and renal dysfunction, and the intraoperative hyperglycemia are significant predictors of prolonged ICU stay. The early identification of patients at risk could allow the efficient ICU resources' allocation and the reduction of healthcare costs. This would contribute to nursing care planning depending on the availability of healthcare personnel and ICU bed capacity.

Major predictors of long-term clinical outcomes after coronary revascularization in patients with unprotected left main coronary disease: analysis from the MAIN-COMPARE study

BACKGROUND

The clinical characteristics that identify high-risk subsets of patients with unprotected left main coronary artery disease undergoing percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) have not been well established.

METHODS AND RESULTS

Between January 2000 and June 2006, 2240 patients with unprotected left main coronary artery disease underwent PCI (n=1102) or CABG (n=1138). Twenty-six preprocedural parameters were evaluated by univariate and multivariate Cox regression analysis to identify independent predictors of all-cause mortality and target-vessel revascularization. Interaction tests were performed to compare heterogeneities of effects of preprocedural parameters depending on the revascularization methods. During follow-up (median of 3.1 years), 187 patients died (78 PCI and 109 CABG) and 149 patients had target-vessel revascularization (121 PCI and 28 CABG). EuroSCORE > or =6 was an independent predictor of death in both groups. Additional independent predictors were chronic renal failure and previous congestive heart failure in the PCI group and age > or =75 years, atrial fibrillation, right coronary artery disease, and left main distal bifurcation disease in the CABG group. Interaction analysis showed no heterogeneities of the effects of variables depending on the revascularization methods. Independent predictors of target-vessel revascularization were acute coronary syndrome and left main distal bifurcation disease in the PCI group and history of coronary intervention in the CABG group. The interaction between previous PCI and treatment remained after adjustment for all independent predictors of target-vessel revascularization (interaction P=0.0345).

CONCLUSIONS

Several clinical characteristics were identified as important preprocedural predictors of long-term adverse outcomes after percutaneous or surgical revascularization in patients with unprotected left main coronary artery disease.

Incidence and predictors of delirium after cardiac surgery: Results from The IPDACS Study

OBJECTIVE

Delirium after cardiac surgery is a serious complication that results in higher morbidity and mortality rates, and prolongs hospitalisation. However, the knowledge base regarding the issue of postoperative delirium is still limited. Therefore, in the current study, we evaluated the incidence and independent perioperative risk factors of delirium after cardiac surgery.

METHODS

The IPDACS Study recruited 563 consecutive patients undergoing cardiac surgery with cardiopulmonary bypass. The subjects were preoperatively examined by psychiatrists using the Mini-Mental State Examination and the Mini International Neuropsychiatric Interview to assess psychiatric comorbidity. Additionally, other variables connected to the patients' medical condition and surgical and anaesthetic procedures were evaluated. A diagnosis of delirium following surgical intervention was based on Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria.

RESULTS

The incidence of postoperative delirium according to DSM-IV criteria was 16.3% (95% confidence interval: 13.5-19.6). Multivariate stepwise logistic regression analysis revealed that advanced age, preoperative cognitive impairment, an ongoing episode of major depression, anaemia, atrial fibrillation, prolonged intubation and postoperative hypoxia were independently associated with delirium after cardiac surgery.

CONCLUSION

According to the current analysis, the aforementioned conditions independently predispose to delirium following cardiac surgery. Since some of these factors can be successfully treated and eliminated preoperatively and postoperatively, this study should be helpful in reducing the risk of delirium and in improving the medical care of patients undergoing cardiac surgery (Clinical Trials Identifier: NCT00784576).

The mechanisms of atrial fibrillation in hyperthyroidism

Atrial fibrillation (AF) is a complex condition with several possible contributing factors. The rapid and irregular heartbeat produced by AF increases the risk of blood clot formation inside the heart. These clots may eventually become dislodged, causing embolism, stroke and other disorders. AF occurs in up to 15% of patients with hyperthyroidism compared to 4% of people in the general population and is more common in men and in patients with triiodothyronine (T₃) toxicosis. The incidence of AF increases with advancing age. Also, subclinical hyperthyroidism is a risk factor associated with a 3-fold increase in development of AF. Thyrotoxicosis exerts marked influences on electrical impulse generation (chronotropic effect) and conduction (dromotropic effect). Several potential mechanisms could be invoked for the effect of thyroid hormones on AF risk, including elevation of left atrial pressure secondary to increased left ventricular mass and impaired ventricular relaxation, ischemia resulting from increased resting heart rate, and increased atrial eopic activity. Reentry has been postulated as one of the main mechanisms leading to AF. AF is more likely if effective refractory periods are short and conduction is slow. Hyperthyroidism is associated with shortening of action potential duration which may also contribute to AF.

Atrial Fibrillation: The New Epidemic of the Ageing World

The prevalence of atrial fibrillation (AF) increases with age. As the population ages, the burden of AF increases. AF is associated with an increased incidence of mortality, stroke, and coronary events compared to sinus rhythm. AF with a rapid ventricular rate may cause a tachycardia-related cardiomyopathy. Immediate direct-current (DC) cardioversion should be performed in patients with AF and acute myocardial infarction, chest pain due to myocardial ischemia, hypotension, severe heart failure, or syncope. Intravenous beta blockers, diltiazem, or verapamil may be administered to reduce immediately a very rapid ventricular rate in AF. An oral beta blocker, verapamil, or diltiazem should be used in persons with AF if a fast ventricular rate occurs at rest or during exercise despite digoxin. Amiodarone may be used in selected patients with symptomatic life-threatening AF refractory to other drugs. Digoxin should not be used to treat patients with paroxysmal AF. Nondrug therapies should be performed in patients with symptomatic AF in whom a rapid ventricular rate cannot be slowed by drugs. Paroxysmal AF associated with the tachycardia-bradycardia syndrome should be treated with a permanent pacemaker in combination with drugs. A permanent pacemaker should be implanted in patients with AF and symptoms such as dizziness or syncope associated with ventricular pauses greater than 3 seconds which are not drug-induced. Elective DC cardioversion has a higher success rate and a lower incidence of cardiac adverse effects than does medical cardioversion in converting AF to sinus rhythm. Unless transesophageal echocardiography has shown no thrombus in the left atrial appendage before cardioversion, oral warfarin should be given for 3 weeks before elective DC or drug cardioversion of AF and continued for at least 4 weeks after maintenance of sinus rhythm. Many cardiologists prefer, especially in elderly patients , ventricular rate control plus warfarin rather than maintaining sinus rhythm with antiarrhythmic drugs. Patients with chronic or paroxysmal AF at high risk for stroke should be treated with long-term warfarin to achieve an International Normalized Ratio of 2.0 to 3.0. Patients with AF at low risk for stroke or with contraindications to warfarin should be treated with aspirin 325 mg daily.