Atrial Maze Research Articles

A propensity matched comparison of robotic vs. traditional minimal access approach for mitral valve repair with concomitant cryoablation.

Atrial fibrillation (AF) occurs frequently in patients with mitral valve disease. Results of cryoablation concomitant with either minimally invasive video-assisted [minimally invasive mitral valve surgery (MIMVS)] or with robotic-assisted (RMV) mitral valve surgery have previously been separately reported. However, there are up-to-date no studies comparing the two procedures in terms of safety, efficacy, and mid-term follow-up. Between January 2017 and March 2022, 294 patients underwent MIMVS, and 187 patients underwent RMV at our institution. After 1:1 propensity score matching using 22 preoperative variables, the study included 104 patients. Group 1 (MIMVS) included 52 patients operated on between 2017-2022 using a minimally invasive video-assisted right-sided mini-thoracotomy. Group 2 (RMV) included 52 patients operated on between 2019-2021 using a robotic-assisted approach. Early and mid-term outcomes were assessed, including maintenance of sinus rhythm. Follow-up was 100% complete at a median follow-up of 2 years. For the entire propensity matched cohort, the median EuroSCORE II was 3.14 [interquartile range (IQR), 1.93-4.99], the median age was 68 (IQR, 61-74) years, and two thirds of the patients were male. Most (72.1%) underwent mitral valve surgery, and 26.9% had an additional tricuspid procedure. Only four patients underwent mitral valve replacement (3.8%). The majority (87.5%) received a left-sided atrial Maze and 12.5% a bi-atrial Maze. The left atrial appendage was occluded in 72.1% cases. Overall, there were no significant differences between the two propensity matched groups in baseline demographics or intra-operative characteristics. Similarly, there were no significant differences in the post-operative short and mid-term outcomes between the two groups. There were no in-hospital or 30-day deaths. At the mid-term survival was similar between groups, log-rank test P=0.056. Maintenance of sinus rhythm at follow-up was 76%. Mitral or double valve repair with concomitant cryoablation can be safely performed with either a MIMVS or RMV approach. Both methods demonstrated outstanding early and mid-term outcomes.

Clinical characteristics and ablation outcomes of recurrent atrial tachyarrhythmia after maze operation -a multicenter study in a single city

Abstract Backgrounds Catheter ablation of atrial tachyarrhythmia after Maze operation is challenging. Methods and Results Twenty-eight cases who underwent catheter ablation of post-Maze procedure atrial tachyarrhythmia (42 sessions; 1.5 per patient) in our 5 teaching affiliate hospitals were retrospectively analyzed. Cox-IV Maze procedure and left atrial Maze were performed in 19 cases and 5 cases, respectively. Median interval between surgery and index ablation was 35 months. In total, 46 atrial tachyarrhythmias were studied. Atrial tachycardia (AT) was the most common (n=36), whereas 4 atrial fibrillation (AF) and 2 focal AT were also observed. Identified tachyarrhythmia circuits were as follows; 16 mitral AT, 9 left atrial localized reentry (4 septal, 3 posterior, 1 left atrial appendage, 1 anterior), 6 right atrial lateral incision-related AT, 5 cavo-tricuspid isthmus (CTI)-dependent AT, 3 roof-dependent AT, 2 right atrial localized reentry (1 coronary sinus (CS), 1 CTI), 2 focal AT (1 para His, 1 CS), 1 bi-atrial AT, 1 pulmonary vein tachycardia, and 1 slow-fast AVNRT (Figure 1). Termination of targeted tachyarrhythmia was confirmed in 34 sessions (81%). AT/AF recurrence free rate at 12, 24, 36 months of follow-up were 91.8%, 81.6%, and 65.3%, respectively (Figure 2). Seven cases underwent multiple sessions (2 2nd sessions, 3 3rd sessions, 2 4th sessions). In these cases, de-novo atrial tachyarrhythmias were detected. Conclusions Most of the tachyarrhythmias after Maze operation were incision/gap-related ATs, among which mitral AT and LA localized reentry were the most prevalent. Although these challenging tachyarrhythmias can be treated with the contemporary mapping techniques, de-novo tachyarrhythmias can emerge in a remote period.Maze AT Figure 1Maze AT Figure 2

Abstract 17670: Double Trouble: Exploring the Rare Coexistence of Right and Left Atrial Thrombus After Left Atrial Appendage Ligation and Maze Procedure

Introduction: Left atrial appendage (LAA) harbors around 90% of thrombus in patients with Atrial Fibrillation(AF) related strokes. Incomplete surgical ligation and LAA stump are independent risk factors for stroke and thromboembolism in AF patients. To our knowledge, we report the first case of biatrial thrombus occurring within 1 week of surgery. Case Presentation: A 76-year-old man with Paroxysmal AF and three-vessel coronary artery disease presented with 3-week exertional and resting shortness of breath and chest pain. Troponins were negative, and EKG revealed AF. Cardiothoracic surgery planned coronary bypass, MAZE procedure, and LAA clipping. Intra-operative transoesophageal echocardiogram(TEE) showed ejection fraction of 35% without LAA clot. Post-operatively, despite anticoagulation(AC) and beta blocker therapy, AF recurred within a week. Subsequent TEE prior to anticipated cardioversion(CV) revealed thrombus on the superior vena cava border of right atrium, anterolateral wall of left atrium and near the mitral valve annulus. CV was deferred, and he was sent to rehab with AC. We hypothesize that the thrombus may be attributed to a stunned atrium caused by ischemic myocardial injury. Our case underscores the need for heightened suspicion of thrombus in individual cases. Discussion: Left atrial appendage occlusion (LAAO) was implemented as stroke prophylaxis strategy in AF during surgical interventions like maze and coronary bypass. while the European Society of Cardiology advises continuing AC after LAAO, studies suggest discontinuing AC in high-risk bleeding patients after successful surgical AF ablation and LAAO if sinus rhythm is maintained for ≥3 months. LAAOS III study shows economic benefit of concomitant surgical LAAO during cardiac surgery in AF patients with CHA2DS2-VASc score ≥2 for stroke prevention. When used alongside AC, it offers incremental benefits. Safety of discontinuing AC after LAAO requires further investigation.

New-onset postoperative atrial fibrillation after mitral valve surgery: Determinants and the effect on survival

ObjectiveMitral valve surgery (MVS) carries substantial risk of postoperative atrial fibrillation (PAF). Identifying patients who benefit from prophylactic left atrial appendage amputation (LAAA) or maze is ill-defined. To guide such interventions, we determined preoperative predictors of PAF and investigated 3-year survival of patients with PAF. MethodsWe performed a retrospective analysis of patients undergoing isolated MVS (N = 670) between 2011 and 2021. Patients with preoperative atrial fibrillation, LAAA or pulmonary vein isolation were excluded. Patient characteristics were compared between those without PAF and those who developed transient or prolonged PAF. Predictors of any PAF and prolonged PAF were identified using multivariable regression analysis. ResultsIn total, 504 patients without preoperative atrial fibrillation underwent isolated MVS. Of them, 303 patients (60.2%) developed PAF; 138 (27.3%) developed transient and 165 (32.7%) developed prolonged (beyond 30 days) PAF. Patients with PAF were older (65.7 vs 54.3 years, P < .001), with larger left atria (4.8 vs 4.3 cm, P < .001), greater prevalence of hypertension (60% vs 47.8%, P < .05), and were New York Heart Association class III/IV (36% vs 8.5%, P < .001). Independent predictors of PAF included left atria volume index (odds ratio [OR], 1.02; P < .003), older age (OR, 1.04; P < .001), heart failure (OR, 6.73; P < .001), and sternotomy (OR, 2.19; P < .002). Age, heart failure, and sternotomy were independent predictors of prolonged PAF. Patients with PAF had greater mortality at 3 years compared with those without PAF (5.3% vs 0.5%, P < .005). On multivariable analysis, PAF was associated with increased mortality (hazard ratio, 7.81; P < .046). ConclusionsPAF is common after MVS and associated with late mortality. Older age, advanced heart failure, and sternotomy are associated with prolonged PAF. These factors may identify patients who would benefit from prophylactic LAAA or ablation during MVS.

Abstract 15040: Atrial Arrhythmia Burden and Mortality in Patients With Congenitally Corrected Transposition of The Great Arteries (ccTGA)

Background: Patients with ccTGA have a high incidence of atrial arrhythmias and premature failure of the systemic right ventricle. We sought to better define this risk. Methods: A retrospective review of all clinical data for patients with ccTGA followed at a large tertiary care institution was performed. The primary outcome was a composite of death and cardiac transplantation. Results: A cohort of 165 patients (age 41±16 years, 53% male) were followed for 11±8 years; 41 patients died, 7 underwent cardiac transplantation, and 4 underwent VAD placement. Male sex (HR 2.7, p=0.002), older age (HR 1.04, p&lt;0.001), clinical heart failure symptoms (HR 7, p&lt;0.001), heart failure hospitalization (HR 4.9, p&lt;0.001), syncope (HR 1.8, p=0.04) and pulmonary hypertension (HR 2.77, p&lt;0.001) were significant predictors of the primary outcome. Atrial fibrillation (HR 3.5, p=0.002), atrial flutter (HR 3.05, p=0.04), and prolonged QRS duration (HR 1.01, p=0.004) on the first ECG, as well as right and left atrial enlargement (HR 4, p&lt;0.001 and 3.7, p&lt;0.003) and severe systemic AV valve regurgitation (HR 3.8, p=0.03) on the first echocardiogram were associated with poor outcomes. Atrial arrhythmias occurred in 110(67%) patients: atrial fibrillation in 75(45%), atrial flutter in 50(30%), and supraventricular tachycardia in 16(9.7%) patients. Arrhythmias were largely asymptomatic in 109(66%) patients, while 25(14.5%) experienced palpitations, dizziness or presyncope, and 10(6%) presented with decompensated heart failure. Cardioversion and antiarrhythmic therapy were utilized in 53(32%) patients. Surgical pulmonary vein isolation or atrial MAZE were performed in 15(9%) patients, cryoablation of the CTI in 3 patients, and surgical ablation of an accessory pathway in 2 patients. One or more catheter ablation procedures were also performed in 18(11%) patients. Conclusions: Atrial fibrillation and flutter, heart failure, prolonged QRS duration, systemic AV valve regurgitation and pulmonary hypertension predict worse outcomes in ccTGA. Although asymptomatic in a majority of patients, atrial arrhythmias are associated with significant morbidity and mortality. Whether a rhythm control strategy even in asymptomatic patients may improve outcomes remains unknown.

Abstract 16851: Simultaneous Mitral Valve Replacement, Aortic Valve Replacement, Tricuspid Valve Repair, Left Atrial Appendage Ligation, Maze Procedure And Cabg In A 57-year Old Female With History Of Tavr And Severe Mitral Annular Calcification

Background: Open heart surgery is preferred for patients with multiple valvular issues with conflicting physiology. Case: A 57-year-old female with a past medical history of Type I Diabetes Mellitus complicated by kidney &amp; pancreatic transplant in 1999 s/p failed kidney transplant in 2016 subsequently back on dialysis, aortic stenosis leading to Transcatheter Aortic Valve Replacement (TAVR) in 2016 who presented to the hospital for profound cardiogenic shock and was found to have severe tricuspid regurgitation, severe mitral stenosis secondary to mitral annular calcification with severe concentric hypertrophy of left ventricle. Decision Making: Her conflicting right and left heart physiology due to Tricuspid Regurgitation and Mitral Stenosis was very difficult to manage medically. She was not deemed a candidate for a heart transplant due to a history of a failed kidney transplant. She underwent surgery which included Mitral Valve Replacement, explant TAVR and repeat aortic valve replacement, Tricuspid repair, Left atrial appendage ligation and maze procedure, and CABG x1 with saphenous vein graft to PDA. She stayed on V-V extracorporeal membrane oxygenation (ECMO) post-operatively and was discharged on post-operative Day # 14. Conclusion: Severe tricuspid Regurgitation &amp; coexisting mitral stenosis pose a dilemma for medical management and only feasible option is surgery which could be extremely challenging.

Abstract 10951: Clinical Outcome of Maze Procedure for Atrial Fibrillation Combined with Mitral Valve Disease and Tricuspid Regurgitation

Introduction: The surgical strategy for atrial fibrillation (AF) combined with mitral valve (MV) disease are still controversial whether biatrial or left atrial maze procedure should be performed concomitantly. Hypothesis: Our retrospective study aimed to evaluate the long-term results of two kinds of maze procedure combined with MV surgery and identify the factors involved in AF recurrence. Methods: We enrolled 88 patients from January 2010 to December 2020 who underwent MV surgery with maze procedure concomitantly. The patients were divided into two groups; biatrial maze, group F: n=42 and left atrial maze, group L: n=46). Primary endpoint was AF recurrence and we also evaluated early and late complication and preoperative and operative factors related to AF recurrence. The average follow-up term was 2.8 years. Results: Preoperative factors of long-standing AF and TR grade were significantly higher in group F than group L (P=0.004, 0.02, respecively). Consequently, tricuspid annuloplasty (TAP) was performed significantly frequent in group F than group L (P=0.002). We encountered 2 hospital deaths (4.4%) due to postoperative cerebral hemorrhage and AMI in group L. There was 1 case (2.2%) required pacemaker implantation (PMI) during hospitalization in group L and 3 cases (7.1%) requiring PMI in Group F in late-period. The AF recurrence rates at 1 and 5-year follow-ups between Group F and Group L were not significantly different (24.4% and 28.4% vs. 22.9% and 32.4%, P =0.79). However, the AF recurrence rate in group L with TAP is significant high than those of the other groups (group F 24.4% and 28.4%, group L with TAP 44.3% and 56.7%, and group L without TAP 7.7% and 14.3% at 1 and 5 years, respectively p =0.005). Subject with group L with TAP were associated with a high risk of AF recurrence, with an adjusted OR of 2.4 (95% CI: 1.31-4.45, P =0.005). Conclusions: Our study demonstrated that both concomitant maze procedure was effective for preventing AF recurrence. However, it is also revealed that left atrial maze with TAP significantly increased AF recurrence. It was suggested that preoperative right atrial load was involved in primary occurrence of AF and left atrial maze alone might not control AF recurrence in such situation.

Bi-atrial or left atrial ablation of atrial fibrillation during concomitant cardiac surgery: A Bayesian network meta-analysis of randomized controlled trials.

Surgical ablation of atrial fibrillation (AF) has become a routine procedure during concomitant cardiac surgery, however, the extension of lesion sets remaincontroversial. We sought to compare the relative benefit and risk of different lesion sets through a Bayesian network meta-analysis (NMA). Pubmed, Embase, and Cochrane Trialsdatabases were searched for randomized controlled trials (RCTs) comparing the rhythm outcome of AF patients undergoing pulmonary vein isolation (PVI), left atrial Maze (LAM), bi-atrial Maze (BAM), or no ablation during concomitant cardiac surgery. An NMA was conducted to explore the difference of over 1 year AF freedom as well as risks for early mortality and permanent pacemaker implantation (PPMI). A total of 2031 patients of 19 RCTs were included. PVI, LAM, and BAM (OR[95% Cr.I]: 5.02 [2.72, 10.02], 7.97 [4.93, 14.29], 8.29 [4.90, 14.86], p < .05) demonstrated higher freedom of AF compared with no ablation, however, no significant difference of rhythm outcome was found among the three ablation strategies based on the random-effects model. BAM was associated with an increase in early mortality when compared with no ablation (OR[95% Cr.I]: 4.08 [1.23, 17.30], p < .05), while none of the remaining comparisons reached statisticaldifference in terms of early mortality and PPMI. Bi-atrial ablation is notsuperior to left atrial ablation strategies in reducing AF recurrence for un-selected surgical patients. BAM has a higher risk of early mortality than no ablation, but no difference was found between bi-atrial and left atrial ablation in regard to early mortality and PPMI based on the current evidence.

Cone repair for Ebstein’s anomaly and atrial fibrillation ablation in an adult patient

We present a 52-year-old woman with Ebstein’s anomaly not previously treated. In this subset of patients, there are no clear guidelines regarding the best surgical strategy for treating the tricuspid valve: replace it or repair it. In this case, extensive repair of the tricuspid valve and the right ventricle is achieved using the cone repair technique popularized by Dr. José Pedro Da Silva. Because the patient also presented with symptomatic paroxysmal atrial fibrillation, a right atrial maze procedure combined with isolation of the pulmonary veins was performed using both radiofrequency and cryotherapy. At the last follow-up, 2 years after the repair, the patient is asymptomatic and maintains sinus rhythm. The last echocardiogram showed mild tricuspid regurgitation with normal right ventricular function.

Early outcomes of usage of cryoFORM® probe for cryomaze procedure in congenital heart surgery.

This study aimed to evaluate the early outcomes of patients who underwent a concomitant therapeutic maze procedure for congenital heart surgery. Between 2019 and 2020, eight patients underwent surgical cryoablation by using the same type of cryoablation probe. Three patients had atrial flutter, two had Wolf-Parkinson-White syndrome, two intra-atrial reentrant tachycardia, and one had atrial fibrillation. Four patients underwent electrophysiological study. Preoperatively, one patient was on 3, two were on 2, five were on 1 antiarrhythmic drug. Six patients underwent right atrial maze and two underwent bilateral atrial maze. Five out of six right atrial maze patients underwent right atrial reduction. Nine different lesion sets were used. Some of the lesions were combined and applied as one lesion. In Ebstein's anomaly patients, the lesion from coronary sinus to displaced tricuspid annulus was delicately performed. The single ventricle patient with heterotaxy had junctional rhythm at the time of discharge and was the only patient who experienced atrial extrasystoles 2 months after discharge. Seven of the eight patients were on sinus rhythm. No patient needed permanent pacemaker placement. Cryomaze procedure can be applied in congenital heart diseases with acceptable arrhythmia-free rates by selecting the appropriate materials and suitable lesion sets. The application of cryomaze in heterotaxy patients can be challenging due to differences in the conduction system and complex anatomy. Consensus with the electrophysiology team about the choice of the right-left or biatrial maze procedure is mandatory for operational success.

Comparison of biatrial and left atrial maze procedure in concomitant cardiac procedures

Comparison of biatrial and left atrial maze procedure in concomitant cardiac procedures

Five-year results of a modified left atrial maze IV procedure in the treatment of atrial fibrillation: a randomized study.

BackgroundThe left atrial maze IV (LAM‐IV) alone has been used to eliminate atrial fibrillation (AF) without severe right heart diseases. However, we felt that it could be improved and developed a modified LAM‐IV (MLAM‐IV). In this prospective trial, we aimed to investigate 5‐year clinical outcomes of AF in patients treated by the novel MLAM‐IV technique.MethodsBetween September 2012 and October 2013, 120 patients who underwent valve surgery and bipolar radiofrequency ablation for AF were randomized into the LAM‐IV group (n = 60) or MLAM‐IV group (n = 60). At postoperative follow‐up examinations, data were recorded at 1, 3 and 6 months, and annually thereafter.ResultsThe mean ablation time and postoperative ventilation time were shorter in the MLAM‐IV group than in the LAM‐IV group (P < 0.001 and P = 0.03, respectively). At 5 years, the rate of freedom from AF was 69.0% in the MLAM‐IV group and 60.0% in the LAM‐IV group (hazard ratio 0.71, 95% confidence interval 0.39 to 1.32, P = 0.42). There were no differences with respect to the early operative mortality and major complications, late mortality, and major adverse events.ConclusionsThe MLAM‐IV provides a technically simpler ablation process. The MLAM‐IV was associated with less ventilation support in the early postoperative period. The long‐term efficacy of the MLAM‐IV in the treatment of AF is comparable to that of the LAM‐IV.

Left atrial maze procedure using diathermy and high-frequency ultrasound as an adjunct to mitral valve replacement in mitral valve disease with atrial fibrillation: a comparative study.

Mitral valve disease is often complicated with atrial fibrillation (AF). Conventional treatment for AF has now been replaced by various energy sources. Our purpose was to evaluate a cost-effective and efficient energy source for performing the Maze procedure. We evaluated and compared diathermy and high-frequency ultrasound as energy source to create maze lines, in terms of outcome. Forty patients with mitral valve disease requiring mitral valve replacement and in atrial fibrillation were included in the study. Twenty patients underwent the Maze procedure using diathermy and 20 using high-frequency ultrasound (Harmonic scalpel probe). All Maze lines were made endocardially from within the cavum of the left atrium isolating the pulmonary veins. All patients were assessed by standard 12 lead electrocardiogram (ECG) in the postoperative period as well as in each follow up visit. Left atrial appendage was ligated in those having left atrium (LA) clot. Sinus rhythm was restored in 95% of patients in the immediate postop period in diathermy group as compared to 90% in the high-frequency ultrasound group. At 3months, 90% were in sinus rhythm in the diathermy group and 85% in the high frequency ultrasound (HFU) group. Statistically significant differences between groups were observed in the following variables: cardiopulmonary bypass (CPB) time (p = 0.011), cross clamp time (p = 0.019), maze time (p = 0.00), and in hospital stay (p = 0.05). Both energy sources were safe, time sparing, effective, and simple; however, the diathermy took less time to perform maze than the HUF and the total CPB time and cross clamp time was less in the diathermy group.

Long-term results of atrial maze surgery in patients with congenital heart disease.

Recurrent atrial tachycardia is common after repair of many types of congenital heart disease, and surgical ablation with a maze procedure represents a potential treatment strategy. The objective of this study is to report a single-centre 19 years' experience with maze surgery in congenital heart patients. Patients undergoing maze procedure concomitantly with cardiac surgical procedures were retrospectively analysed. The maze procedure was classified as therapeutic if the patient demonstrated preoperative atrial arrhythmias, or as prophylactic if done because the patient was considered high risk for post-operative arrhythmias. Acute outcomes and longer-term freedom from atrial arrhythmias were analysed. Maze surgery was performed in 166 patients: 137 in the therapeutic group, and 29 in the prophylactic group. The most common congenital heart lesion was single ventricle for the therapeutic group (27%) and Ebstein's anomaly for the prophylactic group (76%). Surgery consisted of a right atrial maze in 63%, left atrial maze in 4%, and bilateral maze in 33%. There were no direct complications or mortality related to the maze procedure itself. For the therapeutic group, freedom from arrhythmias was 82% and 67% at 1 and 5 years post-maze. Younger age at the time of surgery correlated with a lower long-term recurrence risk. Maze procedure at the time of an elective anatomic surgery is reasonably effective to prevent and treat atrial arrhythmias in patients with congenital heart disease at short- and mid-term, with low morbidity and mortality.

Anesthetic Management of Total Thoracoscopic Left Atrial Maze Procedure for Chronic Atrial Fibrillation—A Single-Institution Experience

Anesthetic Management of Total Thoracoscopic Left Atrial Maze Procedure for Chronic Atrial Fibrillation—A Single-Institution Experience

Left atrial maze efficacy for treatment of concomitant atrial fibrillation with mitral valve disease

Objective This study aims to compare the efficacy of mitral valve surgery with left atrial maze versus isolated mitral valve surgery. Background Atrial fibrillation (AF) is the most common arrhythmia in clinical practice, especially with mitral valve disease. It represents a significant health burden especially with the associated thromboembolic complications. Several surgical approaches have been developed. The most effective one is Cox-Maze III procedure using cut-and-sew technique. Recently, surgical ablation has been transformed into an easier and faster procedure using radiofrequency, microwave, and cryothermal energy. Patients and methods This is a prospective cohort study conducted after the approval of the Human Ethics Committee of Faculty of Medicine, Menoufia University. A total of 100 patients with permanent AF and concomitant mitral valve disease have been recruited. The patients were allocated into two equal groups. Group A included mitral valve surgery and left atrial maze procedure, whereas group B included mitral valve surgery without left atrial maze. Results Group A had significant longer bypass and clamp times than group B (P Conclusion Left atrial maze with mitral valve surgery results in a better outcome in terms of myocardial function and dimensions. In addition, sinus rhythm restoration has the potential benefit of reducing the incidence of thromboembolic complications.

Para-atrial non-acute mediastinal hematoma after left atrial maze procedure mimicking tumor in a patient with treated melanoma

IntroductionThe Cox Maze III procedure is considered the gold standard open surgical procedure for management of atrial fibrillation. This article outlines a unique case of a para-atrial mediastinal hematoma following a bilateral thoracoscopic left atrial Maze procedure mimicking malignancy. ReportA 60-year-old male, with past history of melanoma, underwent bilateral thoracoscopic left atrial mini maze procedure with radiofrequency energy and exclusion of the left atrial appendage. Seven months later, a chest computed tomography (CT) scan was performed to evaluate for pulmonary embolism. The CT scan unexpectedly showed an ill-defined, heterogeneous para-atrial mass immediately superior to the left atrium concerning for tumor and mediastinal adenopathy. The mass was moderately hypermetabolic on subsequent 2-[fluorine-18]fluoro-2-deoxy-d-glucose (FDG) positron emission tomography (PET) scan. A follow-up PET/CT three months later demonstrated near-complete resolution of the para-atrial mass with minimal residual hematoma. ConclusionNon-acute mediastinal hematoma following a maze procedure can potentially be confused with a tumor mass and/or lymphadenopathy on CT and FDG PET/CT. With knowledge of the potential for false-positive FDG uptake in a hematoma, the lesion was monitored, and unnecessary biopsy was avoided.

Successful surgical ablation of atrial fibrillation does not disturb long-term sinus rhythm variability.

Surgical ablation of atrial fibrillation (AF) aims to restore normal sinus rhythm while protecting the sinus node from surgical damage. Surgical lesions may affect autonomic neural structures and influence physiological heart rate variability (HRV). The primary aim of this study was to describe long-term dynamics of HRV after successful surgical ablation of AF. The secondary aim was to compare sinus node function after successful ablation of AF with either left atrial modified Maze procedure or epicardial pulmonary vein isolation after long-term follow-up. This retrospective study included 75 patients who underwent successful ablation of paroxysmal or persistent AF (53 patients, 71%) and long-standing persistent AF (22 patients, 29%). Standard variables were selected to describe HRV and the minimal and mean heart rates. In all patients, a 24-h Holter ECG study was performed preoperatively, at hospital discharge and after 3, 6, 12 and 24 months. A significant reduction in the main HRV parameters and an increase in heart rate were observed at discharge when compared with the preoperative period. During follow-up, all HRV parameters returned to preoperative levels. No significant differences were observed in HRV parameters and HR between the modified Maze and pulmonary vein isolation procedure groups at any time. Successful surgical ablation of paroxysmal, persistent and long-standing persistent AF using either pulmonary vein isolation or modified left atrial Maze procedure does not disrupt long-term HRV. A significant early postoperative reduction in HRV with a gradual increase in the following months is typical in patients after surgical restoration of sinus rhythm.

Pericardial Tamponade: A Rare Etiology of Acute Liver Failure

Acute liver failure is defined as severe hepatic injury within 26 weeks of an insult without prior cirrhosis or liver disease. Criteria for diagnosis include both synthetic liver dysfunction (INR>1.5) and hepatic encephalopathy. Acute liver failure has an annual incidence of 2000 cases in the United States and a mortality approaching 50%. Here we report acute liver failure as the presenting syndrome for pericardial tamponade. A 57-year-old man with refractory paroxysmal atrial fibrillation and no history of hepatic disease presented to an outside hospital with progressive non-bloody, non-bilious emesis. The patient underwent an unsuccessful left atrial hybrid maze procedure 3 weeks prior. Over his 5-day hospitalization, he was treated with anti-emetics for presumed gastroenteritis. However, routine exam and labwork revealed progressive mental status changes, increases in AST/ALT to 938/1000 mg/dL, and an INR of 4.1 - all of which were normal on admission. Given these findings and concern for acute liver failure, the patient was transferred to our hospital for further evaluation. Upon arrival, the patient was afebrile, pulse 87 bpm, and blood pressure of 96/69 mmHg. Physical exam was notable for somnolence, asterixis, scleral icterus, elevated jugular venous distention, and a distended abdomen. Laboratory studies confirmed elevated AST/ALT and INR. Viral and autoimmune hepatitis serologies were unremarkable. Abdominal ultrasound with doppler demonstrated normal hepatic contour with no venous thrombosis. Chest radiograph revealed a globular cardiac silhouette and a trans-thoracic echocardiogram revealed a pericardial effusion with evidence of hemodynamic compromise. A pericardial drain was placed, removing 700 mL of hemorrhagic fluid from the pericardial sac. Within 3 days, the patient's mental status, synthetic function, and hepatic indices improved, remaining stable on outpatient follow-up. This case highlights a rare etiology of acute liver failure. The patient developed pericardial tamponade, an infrequent but known complication of a hybrid maze procedure. The pericardial tamponade led to the development of poor forward flow, right-sided venous congestion, an ultimately hepatic ischemia. Ischemic etiologies of acute liver failure can occur in >50% of cases without a documented hypotensive event, which likely occurred in our patient. This case highlights how clinicians must remain vigilant for rare manifestations of highly mortal diseases.

Long-Term Results of Surgical Atrial Fibrillation Radiofrequency Ablation: Comparison of Two Methods

This retrospective study aimed to evaluate the long-term results of two kinds of surgical atrial fibrillation radiofrequency ablations in concomitant cardiac operations. We enrolled 129 patients from January 2006 to December 2015 and performed cardiac operations concomitantly with surgical atrial fibrillation. The patients were divided into a biatrial MAZE group (94 patients) and a left atrial MAZE group (35 patients). A preoperative baseline was compared with intraoperative and postoperative data. Similarly, complications and follow-up results were compared. A matching process based on propensity-score was performed to equalise the potential prognostic factors in both groups and to formulate a balanced 2:1 matched cohort study. There were four deaths (4.3%) in the biatrial MAZE group and one death in left atrial MAZE group due to multiple organ failures followed by low cardiac output. No permanent pacemaker implantations were used in either group. The sinus rhythm maintenance rates at the 6-month, 1-year, 6-year and 8-year follow-ups between the biatrial MAZE group and the left atrial MAZE group were not significantly different (84.7%, 83.3%, 67.3%, and 58.8% vs. 84.9%, 77.4%, 61.1%, and 50%, p>0.05). Similarly, between the propensity-score matched groups, there were no significant differences. The left atrial MAZE ablation for the patients with mitral valve diseases who needed open cardiac operation was safe and effective when compared with the biatrial MAZE ablation group.