Concomitant ablation of atrial fibrillation: New pacemakers and early rhythm recovery.

OBJECTIVE: New permanent pacemaker (PPM) implantation after concomitant atrial fibrillation (AF) ablation has been associated with surgical ablation (SA). We sought to determine factors for PPM use as well as early rhythm recovery. METHODS: From 2004 through 2019, 6135 patients underwent valve surgery and were grouped: No AF (n = 4584), AF no SA (n = 346), and AF with SA (n = 1205) to evaluate predischarge PPM and 3-month rhythm recovery (intrinsic heart rate >40 beats per minute). RESULTS: Overall, 282 (4.6%) patients required a predischarge PPM: atrioventricular node dysfunction in 75.3%, sick sinus syndrome in 19.1%, both (5%), and indeterminate (0.7%). Patients with AF had more PPMs: AF with SA (7.9%) versus AF no SA (6.9%) versus No AF (3.6%) (P < .001). For patients with AF, PPM rates were not significantly higher for ablation patients (7.6% SA vs 6.9% AF no SA; P = .56). There were differences in PPM by SA lesion set (biatrial 12.8%; left atrial only 6.1%; pulmonary vein isolation 3.0%; P < .001). Among patients with AF treated with 3-month PPM follow-up, rhythm recovery was common (35 out of 62 [56.5%]) and did not differ by lesion set. Rhythm recovery was seen in 63 out of 141 (44.7%) in the atrioventricular node dysfunction group versus 24 out of 35 (68.6%) in the sick sinus syndrome group (P = .011). In propensity score-matched groups, late survival was similar (P = .63) for new PPM patients. CONCLUSIONS: Avoiding conduction system trauma and delaying implantation reduces the need for postoperative PPM. Rhythm recovery within 3 months is frequent, especially for patients with sick sinus syndrome. A conservative approach to the implantation of a new PPMs is warranted.

Implementation of a direct-to-operating room aortic emergency transfer program: Expedited management of type A aortic dissection.

INTRODUCTION: Type A Aortic Dissection (TAAD) is a surgical emergency with a time-dependent rate of mortality. We hypothesized that a direct-to-operating room (DOR) transfer program for patients with TAAD would reduce time to intervention. METHODS: A DOR program was started at an urban tertiary care hospital in February 2020. We performed a retrospective study of adult patients undergoing treatment for TAAD before (n = 42) and after (n = 84) implementation of DOR. Expected mortality was calculated using the International Registry of Acute Aortic Dissection risk prediction model. RESULTS: Median time from acceptance of transfer from emergency physician to operating room arrival was 1.37 h (82 min) faster in DOR compared to pre-DOR (1.93 h vs 3.30 h, p < 0.001). Median time from arrival to operating room was 1.14 h (72 min) faster after DOR compared to pre-DOR (0.17 h vs 1.31 h, p < 0.001). In-hospital mortality was 16.2% in pre-DOR, with an observed-to-expected (O/E) ratio of 1.03 (p = 0.24) and 12.0% in the DOR group, with an O/E ratio of 0.59 (p < 0.001). CONCLUSION: Creation of a DOR program resulted in decreased time to intervention. This was associated with a decrease in observed-to-expected operative mortality. The transfer of patients with acute type A aortic dissection to centers with direct-to-OR programs may result in decreased time from diagnosis to surgery.

Vancomycin-resistant Enterococcus outbreak in a pre- and post-cardiothoracic transplant population: Impact of discontinuing multidrug-resistant organism surveillance during the coronavirus disease 2019 pandemic.

INTRODUCTION: Many institutions suspended surveillance and contact precautions for multidrug-resistant organisms (MDROs) at the outset of the coronavirus disease 2019 (COVID-19) pandemic due to a lack of resources. Once our institution reinstated surveillance in September 2020, a vancomycin-resistant Enterococcus (VRE) faecium outbreak was detected in the cardiothoracic transplant units, a population in which we had not previously detected outbreaks. METHODS: An outbreak investigation was conducted using pulsed-field gel electrophoresis for strain typing and electronic medical record review to determine the clinical characteristics of involved patients. The infection prevention (IP) team convened a multidisciplinary process improvement team comprised of IP, cardiothoracic transplant nursing and medical leadership, environmental services, and the microbiology laboratory. RESULTS: Between December 2020 and March 2021, the outbreak involved thirteen patients in the cardiothoracic transplant units, four index cases, and nine transmissions. Of the 13, seven (54%) were on the transplant service, including heart and lung transplant recipients, patients with ventricular assist devices, and a patient on extracorporeal membrane oxygenation as a bridge to lung transplantation. Four of 13 (31%) developed a clinical infection. DISCUSSION: Cardiothoracic surgery/transplant patients may have a similar risk for VRE-associated morbidity as abdominal solid organ transplant and stem cell transplant patients, highlighting the need for aggressive outbreak management when VRE transmission is detected. Our experience demonstrates an unintended consequence of discontinuing MDRO surveillance in this population and highlights a need for education, monitoring, and reinforcement of foundational infection prevention measures to ensure optimal outcomes.

Staged hybrid totally thoracoscopic maze and catheter ablation for atrial fibrillation.

INTRODUCTION: Atrial fibrillation (AF) is a growing health problem and is associated with increased risk of stroke. The Cox-Maze surgical procedure has offered the highest success rate, but utilization of this technique is low due to procedure invasiveness and complexity. Advances in catheter ablation and minimally invasive surgical techniques offer new options for AF treatment. METHODS: In this review, we describe current trends and outcomes of minimally invasive treatment of persistent and long-standing persistent AF. RESULTS: Treatment of persistent and long-standing persistent AF can be successfully treated using a team approach combining cardiac surgery and electrophysiology procedures. With this approach, the 1-year freedom from AF off antiarrhythmic drugs was 85%. DISCUSSION: There are a variety of techniques and approaches used around the world as technology evolves to help develop new treatment strategies for AF. Our report will focus on a hybrid treatment approach using surgical and electrophysiology approaches providing enhanced treatment options by replicating Cox-Maze IV lesions using skills from each specialty. Closure of the left atrial appendage as part of these procedures enhances protection from late stroke. A team approach provides a cohesive evaluation, treatment, and monitoring plan for patients. Development of successful, less invasive treatment options will help address the growing population of patients with AF.

A history of collaboration between electrophysiologists and arrhythmia surgeons.

INTRODUCTION: The notion that medically-refractory arrhythmias might one day be amenable to interventional therapy slowly began to appear in the early 1960's. At that time, there were no "interventional electrophysiologists" or "arrhythmia surgeons" and there was little appreciation of the relationship between anatomy and electrophysiology outside the heart's specialized conduction system. METHODS: In this review, we describe the evolution of collaboration between electrophysiologists and surgeons. RESULTS: Although accessory atrio-ventricular (AV) connections were first identified in 1893 and the Wolff-Parkinson-White (WPW) syndrome was described 37 years later (1930), it was another 37 years (1967) before those anatomic AV connections were proven to be responsible for the clinical syndrome. The success of the subsequent surgical procedures for the WPW syndrome, AV node reentry tachycardia, automatic atrial tachycardias, ischemic and non-ischemic ventricular tachycardias and atrial fibrillation over the next two decades depended on a close, sometimes daily, collaboration between electrophysiologists and surgeons. In the past two decades, that tight collaboration was largely abandoned until the recent introduction of "hybrid procedures" for the treatment of atrial fibrillation. CONCLUSIONS: A retrospective assessment of the 50 years of interventional therapy for arrhythmias clearly demonstrates the clinical benefits of a close collaboration between electrophysiologists and arrhythmia surgeons, regardless of which one is actually performing the intervention.

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.

Propensity Score-Matched Comparison of Right Ventricular Strain in Women and Men Before and After Left Ventricular Assist Device Implantation.

Objective: Adverse events following left ventricular assist device (LVAD) implantation are more common in women than in men, but the impact of gender differences on right ventricular (RV) failure is not well defined. Therefore, we calculated RV strain before and after LVAD implantation in matched groups of men and women to determine if gender differences in RV failure after LVAD might account for the gender differences in overall outcomes. Methods: RV free wall longitudinal strain (FWS) and fractional area change were calculated preoperatively and 3 months postoperatively using speckle-tracking echocardiography analysis. A total of 172 patients (86 women, 86 men) were then propensity score matched (1:1) for comparison. Results: Although women had higher preoperative CHA2DS2-VASc scores and more frequent moderate mitral regurgitation than men (P = 0.018), the preoperative hemodynamic parameters were similar. Preoperative RV-FWS was -6.7% in women and -6.0% in men (P = 0.65). Postoperatively, women had more progression to severe tricuspid regurgitation (TR) than men (15% vs 7%, P = 0.06). At 3 months the RV-FWS was -7.7% in women and -7.0% in men (P = 0.59). Postoperative TR was moderate-severe in 20% of women and in 9% of men (P = 0.001). Women had a higher incidence of venous thromboembolism, cardiac arrhythmias, and bleeding compared with men. Women also had higher mortality rates at discharge and 30 days after surgery, but the survival rates at 5 years were similar. Conclusions: RV strain measurements track standard hemodynamic and echocardiographic parameters and confirm that gender differences in outcomes following LVAD implantation are not related to gender differences in RV failure rates.

Fate of moderate aortic regurgitation after cardiac surgery.

OBJECTIVE: To determine the prevalence of concomitant aortic regurgitation (AR) in cardiac surgery and the outcomes of treatment options. METHODS: Between April 2004 and June 2018, 3289 patients underwent coronary artery bypass, mitral valve, or aortic aneurysm surgery without aortic stenosis. AR was graded none/trivial (score = 0), mild (score = 1+), or moderate (score = 2+). Patients with untreated 2+ AR were compared with those with 0 or 1+ AR, and to those with 2+ AR who had aortic valve surgery. Thirty-day and late survival, echocardiography, and clinical outcomes were compared using propensity score matching. RESULTS: One hundred thirty-eight patients (4.2%) had 2+ AR; and 45 (33%) received aortic valve repair (n = 9) or replacement (n = 36) in the treated group and were compared with 2765 untreated patients with 0 AR and 386 patients with 1+ AR. Valve surgery was more common with anatomic leaflet abnormalities: bicuspid aortic valve (9% vs 0%; P < .01), rheumatic valve disease (16% vs 3%; P < .01), and calcification (47% vs 27%; P = .021). In unadjusted analysis, lower preoperative AR grade was associated with increased 10-year survival (P < .001). At year 10, progression to more-than-moderate AR among moderate AR patients was 2.6% and late intervention rate was 3.1%. In the untreated 2+ AR group, on last follow-up echocardiogram, 58% had improvement in AR, 41% remained 2+, and only 1% progressed to severe AR. CONCLUSIONS: Aortic valve surgery in select patients with concomitant moderate AR can be added with minimal added risk, but untreated AR does not influence long-term survival after cardiac surgery and rarely required late intervention.

Outcomes of 3-day discharge after elective cardiac surgery.

BACKGROUND: Shorter length of stay (LOS) is a welcome consequence of optimized perioperative care. However, accelerated hospital discharge may have unintended consequences. Before implementing an institutional enhanced recovery after surgery protocol, we evaluated the safety of shorter LOS and compared outcomes of patients with shorter LOS (LOS ≤ 3 days) to those with longer LOS (LOS > 3 days). METHODS: We identified all patients undergoing elective cardiac surgery with cardiopulmonary bypass between July 2004 and June 2017. Transcatheter approaches, ventricular assist devices, transplants, and traumas were excluded. Patients were divided into two cohorts, one with shorter hospitalizations (LOS ≤ 3 days) and one with longer hospitalizations (LOS > 3 days). Propensity score matching (PSM) was performed and differences between the two groups were compared. RESULTS: A total of 5,987 patients (63.0 ± 13.8 years old, 34% female) were identified and 131 (2.2%) patients were LOS ≤ 3 days; median STS Risk score was 1.2 (0.6-2.4). PSM resulted in a total of 478 patients (357 LOS > 3 and 121 LOS ≤ 3 days); median STS Risk score was 0.4 (0.3-0.9). LOS ≤ 3 days had lower rates of postoperative atrial fibrillation (2% vs. 19%; p < .001) and major in-hospital complications (0% vs. 9%; p = .001); however, 30-day readmissions (8% LOS ≤ 3 vs. 6% LOS > 3 days; p = .66) and mortality rates (0% vs. 0%) were comparable between the two groups. CONCLUSION: LOS ≤ 3 days was associated with less postoperative atrial fibrillation and fewer major in-hospital complications. LOS ≤ 3 days was not associated with rehospitalization or mortality. Shorter LOS after elective cardiac surgery appears to be a safe practice with favorable outcomes, especially in low operative risk patients.

Surgery and Catheter Ablation for Atrial Fibrillation: History, Current Practice, and Future Directions.

Atrial fibrillation (AF) is the most common of all cardiac arrhythmias, affecting roughly 1% of the general population in the Western world. The incidence of AF is predicted to double by 2050. Most patients with AF are treated with oral medications and only approximately 4% of AF patients are treated with interventional techniques, including catheter ablation and surgical ablation. The increasing prevalence and the morbidity/mortality associated with AF warrants a more aggressive approach to its treatment. It is the purpose of this invited editorial to describe the past, present, and anticipated future directions of the interventional therapy of AF, and to crystallize the problems that remain.

Ablation of atrial fibrillation during coronary artery bypass grafting: Late outcomes in a Medicare population.

BACKGROUND: This study compares outcomes of patients with preoperative atrial fibrillation undergoing coronary artery bypass grafting (CABG) with or without concomitant atrial fibrillation ablation in a nationally representative Medicare cohort. OBJECTIVES: This study examined early and late outcomes in CABG patients with a preoperative history of atrial fibrillation to determine the correlation between surgical atrial fibrillation ablation to mortality and stroke or systemic embolization. METHODS: In the Medicare-linked Society of Thoracic Surgeons database, 361,138 patients underwent isolated CABG from 2006 to 2013; 34,600 (9.6%) had preoperative atrial fibrillation; 10,541 (30.5%) were treated with surgical ablation (ablation group), and 23,059 were not (no ablation group). Propensity score matching was performed using a hierarchical mixed model. Long-term survival was summarized using Kaplan-Meier curves and Cox regression models with robust variance estimation. The stroke or systemic embolization incidence was modeled using the Fine-Gray model. Median follow-up was 4 years. RESULTS: Long-term mortality in propensity score-matched CABG patients (mean age 74 years; Society of Thoracic Surgeons risk score, 2.25) receiving ablation versus no ablation was similar (log-rank P = .30). Stroke or systemic embolization occurred in 2.2% versus 2.1% at 30 days and 9.9% versus 12.0% at 5 years (Gray P = .0091). Landmark analysis from 2 to 5 years showed lower mortality (hazard ratio, 0.89; 95% confidence interval 0.82-0.97; P = .0358) and lower risk of stroke or systemic embolization (hazard ratio, 0.73; 95% confidence interval, 0.61-0.87; P = .0006) in the ablation group. CONCLUSIONS: Concomitant ablation in CABG patients with preoperative atrial fibrillation is associated with lower stroke or systemic embolization and mortality in patients who survive more than 2 years.

Safety of Atrial Fibrillation Ablation With Isolated Surgical Aortic Valve Replacement.

BACKGROUND: Surgical ablation of atrial fibrillation (AF) concomitant with cardiac surgery is a Society of Thoracic Surgeons (STS) class I recommendation, although the AF is frequently ignored. Analysis of the STS Database 30-day outcomes of isolated surgical aortic valve replacement (AVR) with and without AF ablation is presented. METHODS: Data on 87,426 surgical aortic valve replacement patients were extracted from the STS database (version 2.81, 2014-2017) and patients were divided into 3 groups: (1) No preoperative AF, (2) Preoperative AF with concomitant ablation, and (3) Preoperative AF without ablation. The latter 2 groups were propensity score-matched in 1-(up)-to-2 ratio to alleviate covariate imbalances and reduce bias. Thirty-day outcomes were evaluated and compared. RESULTS: Preoperative AF was present in 17.8% (15,596 of 87,426 patients). Ablation was performed in 33.1% (5,167 of 15,596), and 57.7% (2,983) had left atrial appendage closure. Propensity score matching (AF ablated n = 3692; AF non-ablated n = 5724), revealed that there was no difference between the AF ablated and AF non-ablated groups in mortality (2.8% vs 3.0%, respectively; P = .65) or for stroke (1.6% vs 1.7%, respectively; P = .82), but postoperative pacemaker implantation was higher in the AF ablated patients (6.8% AF ablated vs 5.0% AF non-ablated, P < .001). CONCLUSIONS: Despite being a class I recommendation, AF ablation concomitantly with other cardiac surgical procedures remains lower than current guideline recommendation in surgical aortic valve replacement patients. Ablation for AF does not increase the 30-day operative mortality or perioperative morbidity compared with non-ablated patients, although new pacemaker requirements were higher in the AF ablated group.

Outcomes of Sutureless/Rapid Deployment Valves Compared to Traditional Bioprosthetic Aortic Valves.

BACKGROUND: Sutureless/rapid-deployment (SRD) valves for aortic valve replacement (AVR) are new surgical bioprosthetic valves that allow for expedited implantation and facilitate minimally invasive approaches. Although clinical trial data are available for SRDs in the United States, how their clinical outcomes compare with traditional stented bioprosthetic (SBP) valves is unknown in a post-approval, commercial setting. METHODS: The Society of Thoracic Surgery Adult Cardiac Surgery Database was queried for patients who underwent an AVR. Transcatheter AVR cases were excluded. Thirty-day outcomes were compared between SRD valves (Perceval S [LivaNova, Houston, TX] and Intuity Elite [Edwards Lifesciences, Irvine CA]) and SBP valve patients. The SRD and SBP patients were propensity score-matched in a 1:(up to) 3 ratio. Primary outcome was 30-day mortality and secondary outcomes were major comorbidities, paravalvular regurgitation, and predischarge pacemaker implant. RESULTS: Propensity score matching resulted in 4486 SRD patients and 13,215 SBP patients. The SRD recipients had more permanent pacemakers (11.4% vs 4.9%, P < .001) shorter cross-clamp times (median: 68 vs 86 minutes, P < .001), and fewer full sternotomies (75% vs 77% , P < .024) than SBP but similar 30-day mortality (3.1% vs 3.1%, P = .98) and moderate or greater paravalvular regurgitation (0.2% vs 0.1%, P = .21). CONCLUSIONS: SRD implantation was associated with reduced operative times and smaller incisions. Rates of 30-day mortality, major comorbidities, and perivalvular regurgitation were similar between SRD and SBP patients. Longer follow-up is needed to determine the implications of increased permanent pacemaker implantation rates in SRD patients.

Cryosurgery for Atrial Fibrillation: Physiologic Basis for Creating Optimal Cryolesions.

BACKGROUND: Although cryosurgery has been used to treat cardiac arrhythmias for nearly 5 decades, the mechanism of action and the surgical technique that produces optimal cryolesions for the treatment of atrial fibrillation are still poorly understood. This has resulted in surgical outcomes that can be improved by a better understanding the mechanisms of cryothermia ablation and the proper surgical techniques that take advantage of those mechanisms. METHODS: The cryobiology underlying cryosurgical ablation is described, as are the nuances of cryosurgical techniques that ensure the reliable creation of contiguous, uniformly transmural atrial cryolesions. The oft-misunderstood "2-minute rule" for the application of cryothermia is clarified in detail, along with its variations that depend on target myocardial temperature. RESULTS: The creation of optimal cryolesions depends on cryoprobe temperature, the temperature of the target myocardium, the duration of cryothermia application, and the presence or absence of a "heat sink" or "cooling sink" created by intracavitary blood circulation. Cryothermia kills myocardial cells during both the freezing and thawing phases of cryoablation cycle. The critical lethal temperature for myocardium is -30°C. The slower the target tissue thaws, the higher the percentage of cell death. CONCLUSIONS: The availability of cryosurgical techniques has revolutionized the surgical treatment of atrial fibrillation. By utilizing modern cryosurgical devices and adhering to the technical principles described, surgeons can now perform surgical procedures for atrial fibrillation that are quicker, safer, and as effective as the standard Maze-III/IV procedure.

Cardiac anatomy pertinent to the catheter and surgical treatment of atrial fibrillation.

In the 1980s when surgery was first introduced for the treatment of atrial fibrillation (AF), one would often hear comments like "Every little old grandmother has AF. Why on earth would you operate on someone like that?".

Concomitant atrial fibrillation ablation in patients undergoing coronary artery bypass and cardiac valve surgery.

Surgical ablation of atrial fibrillation (AF) in conjunction with other cardiac surgery is now a class I guideline recommendation. Multiple studies have demonstrated that the concomitant surgical ablation of AF can be performed safely and effectively during valve and coronary artery bypass grafting (CABG) resulting in a return to sinus rhythm postoperatively and improved long-term results. However, the surgical ablation of AF at the time of other cardiac surgery is performed less often than it should be, especially in patients undergoing CABG and aortic valve surgery. Randomized-controlled trials designed to determine the effect of treating AF concomitantly with other cardiac surgical procedures have lacked long-term follow up, but multiple, large observational studies have demonstrated an improved quality of life, a decrease in long-term strokes, and improved late survival in patients who undergo AF ablation. However, the potential survival benefit of concomitant AF ablation was not addressed by either the Society of Thoracic Surgery or American Association for Thoracic Surgery guideline committees. Left atrial appendage closure is an important part of the surgical ablation of AF as it significantly reduces the long-term risk of stroke following cardiac surgery and improves the success of AF treatment. In this study, we update the electrophysiology and surgical community on the recommended surgical techniques for AF ablation and its effect on perioperative morbidity, perioperative mortality, as well as its long-term effects on stroke, quality of life, and survival.

A Hybrid Maze Procedure for Long-Standing Persistent Atrial Fibrillation.

BACKGROUND: Catheter ablation (CA) for long-standing persistent atrial fibrillation (LSPAF) is suboptimal, and open surgical ablation, although more successful, is too invasive to be a first-line therapy. Less invasive hybrid procedures that combine thoracoscopic surgery (TS) with CA have been only marginally more successful for LSPAF than CA alone. METHODS: Joint hybrid procedures for LSPAF are based on the assumption that AF surgery and CA procedures can be guided by intraoperative mapping. However, intraoperative mapping is not always dependable because of the transient nature of the sustaining reentrant drivers. The best results in patients with LSPAF have been attained with the non-guided, anatomy-based surgical Maze-III and Maze-IV procedures. Likewise, a staged TS/CA hybrid procedure that creates a combination of lesions that adhere to the concept of a Maze pattern, that is, a Hybrid Maze-IV procedure, should be more effective for LSPAF. RESULTS: Initial TS includes all lesions of the Maze-IV procedure except the mitral line, coronary sinus lesion, and one right atrial lesion. Follow-up CA at 3 months includes touching up any incomplete TS lesions, a cavotricuspid isthmus lesion, and a mitral line/coronary sinus lesion in the 10% to 15% of patients with post-TS perimitral flutter. This combination of TS and CA lesions creates a complete Maze-IV procedure. CONCLUSIONS: It is possible to create the complete lesion pattern of a Maze-IV procedure with a staged TS/CA hybrid procedure. The success of this Hybrid Maze procedure in patients with LSPAF should be the same as that attained with an open surgical Maze-IV procedure.

De novo atrial fibrillation after mitral valve surgery.

OBJECTIVES: We sought to determine the incidence and risk factors for de novo atrial fibrillation (>90 days after surgery) in patients without preoperative atrial fibrillation. METHODS: From 2004 to 2014, 2261 patients underwent mitral valve surgery; 1288 patients (57%) did not have a history of atrial fibrillation, and 930 patients had rhythm information more than 90 days after surgery. De novo atrial fibrillation and death probabilities were estimated using a semi-competing risks, multi-state model. Univariable and multivariable risk factors for developing atrial fibrillation were identified using the Fine-Gray model. RESULTS: The 5- and 10-year incidences of de novo atrial fibrillation were 14% and 23%, respectively. Univariable risk factors were older age, more complex operations, more tricuspid regurgitation, and congestive heart failure (all P < .05). Patients with degenerative mitral regurgitation were less likely to develop atrial fibrillation (hazard ratio [HR], 0.4; 95% confidence interval [CI], 0.24-0.65; P < .001). Multivariable risk factors for de novo atrial fibrillation were tricuspid valve surgery (HR, 1.80; 95% CI, 1.22, 2.65; P = .003), aortic valve surgery (HR, 1.49; 95% CI, 1.03-2.17; P = .035), and older age (HR, 1.03; 95% CI, 1.02-1.05; P < .001). De novo atrial fibrillation did not affect overall survival (P = .41). Among patients who developed de novo atrial fibrillation, we observed increased use of warfarin (P < .001) and a strong trend toward an increased risk of stroke (P = .055). CONCLUSIONS: De novo atrial fibrillation develops progressively after mitral surgery and is associated with a strong trend toward stroke. Patients at high risk could be studied in a trial to reduce atrial fibrillation.