Quantum Isometries of the finite noncommutative geometry of the Standard Model

We compute the quantum isometry group of the finite noncommutative geometry F describing the internal degrees of freedom in the Standard Model of particle physics. We show that this provides genuine quantum symmetries of the spectral triple corresponding to M x F where M is a compact spin manifold. We also prove that the bosonic and fermionic part of the spectral action are preserved by these symmetries.Comment: 29 pages, no figures v3: minor change

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

Additional bypass graft or concomitant surgical ablation? Insights from the HEIST registry

Background: Surgical ablation for atrial fibrillation at the time of isolated coronary artery bypass grafting is reluctantly attempted. Meanwhile, complete revascularization is not always possible in these patients. We attempted to counterbalance the long-term benefits of surgical ablation against the risks of incomplete revascularization. Methods: Atrial fibrillation patients undergoing isolated coronary artery bypass grafting for multivessel disease between 2012 to 2022 and included in the HEart surgery In atrial fibrillation and Supraventricular Tachycardia registry were divided into complete revascularization, complete revascularization with additional grafts, and incomplete revascularization cohorts; these were further split into surgical ablation and non-surgical ablation subgroups. Results: A total of 8,405 patients (78% men; age 69.3 ± 7.9) were included; of those, 5,918 (70.4%) had complete revascularization, and 556 (6.6%) had surgical ablation performed. Number of anastomoses was 2.7 ± 1.2. The median follow-up was 5.1 [interquartile range 2.1-8.8] years. In patients in whom complete revascularization was achieved, surgical ablation was associated with long-term survival benefit: hazard ratio 0.69; 95% confidence intervals (0.50-0.94); P = .020 compared with grafting additional lesions. Similarly, in patients in whom complete revascularization was not achieved, surgical ablation was associated with a long-term survival benefit of 0.68 (0.49-0.94); P = .019. When comparing surgical ablation on top of incomplete revascularization against complete revascularization without additional grafts or surgical ablation, there was no difference between the 2: 0.84 (0.61-1.17); P = .307, which was also consistent in the propensity score-matched analysis: 0.75 (0.39-1.43); P = .379. Conclusion: To achieve complete revascularization is of utmost importance. However, when facing incomplete revascularization at the time of coronary artery bypass grafting in a patient with underlying atrial fibrillation, concomitant surgical ablation on top of incomplete revascularization is associated with similar long-term survival as complete revascularization without surgical ablation

Surgical ablation of atrial fibrillation with concomitant cardiac surgery: a state-of-the-art review

Patients with preoperative atrial fibrillation (AF) undergoing cardiac surgery face a heightened risk of complications and reduced survival. Concomitant surgical ablation (SA) has shown promise in mitigating the arrhythmic burden, prompting guideline upgrades by major scientific societies. However, SA remains underutilized, with performance rates varying between 22% and 48%, depending on the type of procedure. The goal of this narrative review is to summarize current evidence to aid physicians in decision making regarding AF management during cardiac surgery. This review examines existing literature on the prevalence, management and outcomes of AF in cardiac surgery. We assess epidemiological data, summarize trends in clinical practice and review the rationale and techniques for treating AF surgically. Emerging challenges, including barriers to implementation and novel therapeutic advancements, are also discussed. Evidence underscores the detrimental impact of preoperative AF on perioperative and long-term outcomes, including higher mortality, morbidity and thromboembolic risk. Concomitant SA, particularly the Cox-maze IV procedure, significantly improves sinus rhythm restoration, reduces mortality and mitigates complications like stroke. However, the procedure remains underperformed due to concerns about complexity, prolonged operative time and training gaps. Emerging hybrid techniques, novel mapping systems and technologies like pulsed field ablation may enhance outcomes and broaden SA adoption. Concomitant SA is an effective yet underutilized therapy that can improve survival and reduce AF-related complications in cardiac surgery patients. Addressing implementation barriers and integrating advancements in technology and surgical approaches are key to optimizing patient outcomes