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Background: Postoperative atrial fibrillation (POAF) is one of the most common types of acute AF and can complicate the treatment course of approximately one third of patients undergoing cardiac surgery. Sodium-glucose cotransporter-2 (SGLT2) inhibitors are among the newest antidiabetic drugs which can be therapeutic options for preventing POAF by different mechanisms., Methods: Empagliflozin to Prevent POAF (EMPOAF) is an interventional, investigator-initiated, double-blind, placebo-controlled, multicenter, randomized controlled trial which will be conducted in two referral teaching cardiology hospitals in Tehran. Four-hundred ninety-two adult patients who are scheduled for elective isolated coronary artery bypass graft (CABG) surgery will be randomly assigned to one of the groups of intervention (empagliflozin 10 mg daily) or placebo starting at least 3 days before surgery until discharge. Key exclusion criteria are a history of diabetes mellitus, AF, ketoacidosis, or recurrent urinary tract infections along with severe renal or hepatic impairment, unstable hemodynamics, and patients receiving SGLT2 inhibitors for another indication. The primary outcome will be the incidence of POAF. Key secondary endpoints will be the composite rate of life-threatening arrhythmias, postoperative acute kidney injury, hospitalization length, in-hospital mortality, stroke, and systemic embolization. Key safety endpoints will be the rate of life-threatening and/or genitourinary tract infections, hypoglycemia, and ketoacidosis., Conclusions: EMPOAF will prospectively evaluate whether empagliflozin 10 mg daily can reduce the rate of POAF in patients undergoing elective CABG. Enrolment into this study has started by November 2023 and is expected to be ended before the end of 2025., (© 2024 Wiley Periodicals LLC.)

Background: Patients with moderate-to-severe mitral stenosis (MS) have bee excluded from all major randomized controlled trials (RCTs) comparing non-vitamin K antagonist oral anticoagulants (NOACs) with warfarin in patients with atrial fibrillation (AF)., Methods and Results: In this pilot RCT, 40 patients were randomized to rivaroxaban 20 mg daily or warfarin. No patients experienced symptomatic ischemic strokes and systemic embolic events (the primary composite study outcome) during a 12-month follow-up. No major bleeding was reported. During the follow-up, 18.2% of patients in both groups showed echocardiographic signs of increased thrombogenicity in the left atrial appendage. The rate of silent cerebral ischemia was 13.3% in the rivaroxaban group and 17.6% in the warfarin group at brain magnetic resonance imaging., Conclusion: Our results suggest acceptable efficacy and safety for rivaroxaban in patients with AF and moderate-to-severe MS and are encouraging for larger RCTs in this so far neglected setting (NCT03926156)., (Copyright © 2022. Published by Elsevier B.V.)

Atrial fibrillation (AF) is a morbid and heritable irregular cardiac rhythm that affects about 2%-3% of the population. Patients with early-onset AF have a strong genetic association with the disease; nonetheless, the exact underlying mechanisms need clarification. We herein present our evaluation of a 2-generation Iranian pedigree with early-onset AF. Whole-exome sequencing was applied to elucidate the genetic predisposition. Direct DNA sequencing was utilized to confirm and screen the variants in the proband and his available family members. The pathogenicity of the identified nucleotide variations was scrutinized via either segregation analysis in the family or in silico predictive software. The comprehensive variant analysis revealed a missense variant (c.G681C, p.E227D, rs1477078144) in the human α-dystrobrevin gene (DTNA), which is rare in genetic databases. Most in silico analyses have predicted this variant as a disease-causing variant, and the variant is co-segregated with the disease phenotype in the family. Previous studies have demonstrated the association between the DTNA gene and left ventricular noncompaction cardiomyopathy. Taken together, we provide the first evidence of an association between a nucleotide variation in the DTNA gene and early-onset AF in an Iranian family. However, the genetic testing of AF in the Iranian population is still limited. This finding not only further confirms the significant role of genetics in the incidence of early-onset AF but also expands the spectrum of the gene variations that lead to AF. Additionally, it may have further implications for the treatment and prevention of AF., (© 2022. The Author(s).)

Conventionally, patients have been admitted overnight after atrial fibrillation (AF) catheter ablation. Several centers have recently adopted a same-day discharge (SDD) protocol for patients undergoing AF catheter ablation. We aimed to systematically review the current evidence for the safety and efficacy of SDD after AF catheter ablation. A systematic search was performed in PubMed, Embase, Scopus, Web of Science, and the Cochrane library until August 21, 2021. The risk of bias was assessed with the "Methodological Index for Non-Randomized Studies" (MINORS). The pooled efficacy rate of SDD protocol (defined as the proportion of patients discharged the same day of ablation among the patients who were planned for SDD) was calculated. Meanwhile, pooled major complication rates and early readmission or emergency department (ED) visit rates were evaluated in successful and planned SDD groups separately. Overall, 12 observational studies consisting of 18,065 catheter ablations were included, among which 7320 (40.52%) were discharged the same-day after ablation. The pooled efficacy was 90.3% (95% confidence interval [CI] [82.7-96.0]). The major complication rates were 1.1% (95%CI [0.5-1.9]), and 0.7% (95% CI [0.0-3.1]) in planned SDD and successful SDD groups, respectively. In addition, readmission/ED visit rate were 3.0% (95%CI [0.9-6.1]), and 3.1% (95% CI [0.8-6.5]) in the same groups. There were no significant differences between planned SDD and overnight groups with respect to major complication rate (risk ratio = 0.70, 95%CI [0.35-1.42], p-value = .369). The available data indicates that SDD after AF ablation is safe and efficient. Further prospective and randomized studies are warranted to elucidate the safety of SDD after AF ablation and develop a standardized SDD protocol., (© 2022 The Authors. Clinical Cardiology published by Wiley Periodicals LLC.)

Background: Atrial fibrillation. (AF) is the most common sustained arrhythmia globally and its prevalence is likely to increase in the next decades as a result of increasing age and co-morbidities. There are no data on demographic features, clinical characteristics, associated comorbidities, and practice patterns of AF in Iran., Methods: The Iranian Registry of Atrial Fibrillation (IRAF) is a hospital-based prospective survey of AF patients with a 12-month follow-up. Data were collected on a standardized case report form and entered into a web-based electronic database. This paper reports the baseline characteristics of the IRAF cohort., Results: Between February 2018 and March 2020, a total of 1300 patients (57% Male, mean age, 60 ± 14 years) were enrolled. Palpitations were the most common presenting symptom (66%). The most common cardiac comorbidities were hypertension (52%), heart failure (23.7%), and valvular heart disease (21.8%). AF mainly presented as a paroxysmal pattern (44.6%). Seventy-eight percent of the patients with non-valvular AF had CHA 2 DS 2 -VASc score ≥1 and most (97%) were at low risk for bleeding (HAS-BLED score <3). Rhythm control was given to 55.1% of the patients. Anticoagulation for stroke prevention was provided to 69.5% of the eligible patients, while aspirin was used in 35%., Conclusion: The IRAF Registry has provided a systematic collection of contemporary data regarding the management and treatment of AF in Iran. Oral anticoagulant was used in 69.5%, but aspirin use was still common., (© 2021 John Wiley & Sons Ltd.)

Background: There is paucity of information on clinical characteristics and outcome of patients with familial atrial fibrillation (AF). The present study was aimed to compare clinical profile and outcome of familial AF with those of non-familial AF., Methods: Between February 2017 and February 2018, we enrolled 738 participants (60% men, median age, 51 years in familial AF vs. 61 years in non-familial AF) from Iranian Registry of AF. All patients were followed for 12 months. Clinical characteristics and main outcome measures for AF patients were obtained from patient's medical records., Results: A positive history of AF in first-degree relative was reported in 15.3% of our AF population. Familial AF group were significantly younger than non-familial group (p = 0.001). Concomitant sinus node dysfunction and cardiomyopathies were more common in familial AF group (p = 0.02, p = 0.004, respectively). Patients with familial AF were also likely to receive cardiac devices and AF catheter ablation (all p < 0.05). However, all-cause mortality and thromboembolic events were similar (all p > 0.05)., Conclusions: Familial AF patients were more likely to have associated rhythm disorders and dilated cardiomyopathies. Cardiac interventions were also more common in familial patients. However, they did not differ significantly in their long-term outcome., Competing Interests: Declaration of competing interest All authors who participated in this study had nothing to declare., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Postoperative atrial fibrillation (POAF) is a major complication after cardiac surgery which can lead to high rates of morbidity and mortality, an enhanced length of hospital stay, and an increased cost of care. POAF is postulated to be a multifactorial phenomenon; however, some major pathogeneses have been proposed, including inflammatory pathways, oxidative stress, and autonomic dysfunction. Genetic studies also showed that inflammatory pathways, beta-1 adrenoreceptor variants, G protein-coupled receptor kinase 5 gene variants, and non-coding single-nucleotide polymorphisms in the 4q25 chromosomal locus are involved in this phenomenon. Moreover, several predisposing factors lead to the development of POAF, consisting of pre-, intra-, and postoperative contributors. The main predisposing factors comprise age, prior history of major cardiovascular risk factors, and ischemia-reperfusion injury during surgery. The management of POAF is based on the usual therapies used for non-surgical AF, including medications for either rate control or rhythm control in hemodynamically unstable patients. The perioperative administration of β-blockers and some antiarrhythmic agents has been recommended in major international guidelines. In addition, upstream therapies consisting of colchicine, magnesium, statins, and antioxidants have attenuated the incidence of POAF; however, some uncomfortable side effects developed in large randomized trials. The use of anticoagulation has also resulted in less mortality in patients with POAF at higher risk of thromboembolic events. Despite these recommendations, the actual regimen for the prevention of POAF remains controversial. In this review, we highlight the pathogenesis, predisposing factors, and potential therapeutic options for the management of patients at risk for or with POAF following cardiac surgery.

Background: Statin therapy has been thought to improve outcomes in cardiac surgeries. We aimed to determine the statin effects on the development of postoperative atrial fibrillation (AF), hospital length of stay (LOS), and inflammatory status in patients undergoing cardiac surgeries., Methods: A systematic literature search in databases was performed, until January 2015. Randomized clinical trial (RCT) studies evaluating statin effect on statin-naive patients with sinus rhythm undergoing cardiac surgeries were eligible to be analyzed., Results: Twelve RCTs involving 1116 patients, 559 receiving statin and 557 receiving control regimen, were analyzed. Postoperative AF occurred in 17.9% and 36.1% of patients in the statin and control groups, respectively. The statin therapy was associated with decreases in the postoperative AF (risk ratio [RR] 0.50, 95% confidence interval [CI] 0.41-0.61, P < .000010), hospital LOS (mean difference in days, RR -0.44, 95% CI -0.67 to -0.20, P = .0002), and postoperative C-reactive protein (CRP) compared with control (mean difference in mg/L, RR -12.37, 95% CI -23.87 to -0.87, P = .04). The beneficial effects on AF and CRP were more marked in patients receiving atorvastatin compared to other statins. Decrease in postoperative AF was greater in coronary artery bypass graft surgery compared to that in isolated valvular surgery., Conclusion: Perioperative statin therapy in statin-naive patients with sinus rhythm undergoing cardiac surgeries was associated with decreases in the development of postoperative AF, the hospital LOS, and the CRP level. However, there were insufficient data to provide evidences regarding statin impacts in patients undergoing isolated valvular surgery., (© The Author(s) 2015.)

Background: This study attempted to identify the role of combined conventional and novel echocardiographic techniques in evaluation of left atrial (LA) function to predict the postoperative atrial fibrillation (POAF)., Methods: In this cross-sectional study, subjects with sinus rhythm who were candidates for CABG were enrolled. Preoperative LA function was evaluated by conventional echocardiography and 2-dimensional strain imaging based-velocity vector imaging (VVI). VVI-derived systolic peak positive, early and late diastolic strain rate were measured. Using tissue Doppler study, systolic peak velocities (Sm), early diastole (Em), atrial systole (Am) and AEMi were also measured. The patients were observed during their hospital stay. The primary endpoint of the study was postoperative AF lasting > 5 minutes., Results: POAF occurred in 12.7% of patients. Age, LA volume index (LAVI), LA area, LA empting fraction (LAeF) and cardiopulmonary bypass time were found to be the independent predictors of POAF. TDI-derived velocities were similar in study groups. LA systolic strain rate (SRs) and early diastolic strain rate were impaired in patients with no significant difference between those who developed POAF and those who did not., Conclusions: Conventional echocardiography could be used as a feasible method for evaluating subclinical atrial dysfunction in patients undergoing CABG and the use of VVI- based 2-dimensional strain imaging may need further studies.

Background: There are only limited prospective data on the clinical relevance of current of injury (COI) as a predictor of the midterm performance of active-fixation leads. This study sought to investigate whether it is possible to predict the midterm performance of active-fixation leads using COI recorded at the time of implantation., Methods and Results: One hundred fifty patients (78 men; mean age, 63 ± 19 years) who received active-fixation pacing (n = 201) and defibrillator (n = 51) leads were studied. COI was measured from the intracardiac bipolar electrogram recorded at the time of lead implantation. The study outcome was good lead performance at 6 months, defined as P wave ≥ 1.5 mV, threshold <1.5 V for atrial lead, R-wave ≥ 5 mV, and threshold <1 V for ventricular lead. A total of 102 active-fixation atrial and 150 ventricular leads were implanted. During a 6-month follow-up, invasive intervention was required for seven atrial and seven ventricular leads. In multivariate analysis, COI was the only independent predictor of good outcome for the active-fixation atrial (odds ratio [OR]: 5.67, 95% confidence interval [CI]: 2.18-14.76, P = 0.001) and ventricular leads (OR: 3.99, 95% CI: 1.08-21.26, P = 0.002). Receiver-operating characteristic analysis identified ST-segment elevation ≥2.0 mV for the atrial leads (sensitivity, 75%; specificity, 89%) and ≥10.0 mV for the ventricular leads (sensitivity, 70%; specificity, 87%) as optimal cutoffs for good midterm performance., Conclusions: Midterm performance of active-fixation leads is predictable using COI recorded at the time of lead implantation. A ST-segment elevation ≥2.0 mV in the atrial leads and ≥10.0 mV in the ventricular leads are recommended to improve the lead performance at 6 months., (©2013, The Authors. Journal compilation ©2013 Wiley Periodicals, Inc.)

Atrial fibrillation (AF) is a commonly encountered cardiac arrhythmia. Predicting the conditions under which AF terminates spontaneously is an important task that would bring great benefit to both patients and clinicians. In this study, a new method was proposed to predict spontaneous AF termination by employing the points of section (POS) coordinates along a Poincare section in the electrocardiogram (ECG) phase space. The AF Termination Database provided by PhysioNet for the Computers in Cardiology Challenge 2004 was applied in the present study. It includes one training dataset and two testing datasets, A and B. The present investigation was initiated by producing a two-dimensional reconstructed phase space (RPS) of the ECG. Then, a Poincare line was drawn in a direction that included the maximum point distribution in the RPS and also passed through the origin of the RPS coordinate system. Afterward, the coordinates of the RPS trajectory intersections with this Poincare line were extracted to capture the local behavior related to the arrhythmia under investigation. The POS corresponding to atrial activity were selected with regard to the fact that similar ECG morphologies such as P waves, which are corresponding to atrial activity, distribute in a specific region of the RPS. Thirteen features were extracted from the selected intersection points to quantify their distributions. To select the best feature subset, a genetic algorithm (GA), in combination with a support vector machine (SVM), was applied to the training dataset. Based on the selected features and trained SVM, the performance of the proposed method was evaluated using the testing datasets. The results showed that 86.67% of dataset A and 80% of dataset B were correctly classified. This classification accuracy is in the same range as or higher than that of recent studies in this area. These results show that the proposed method, in which no complicated QRST cancelation algorithm was used, has the potential to predict AF termination.

Background: Approximately 30% of all accessory pathways (APs) are located in the septal area, and understanding the electrocardiographic and electrophysiologic of these APs is crucial for safe and effective ablation of these pathways., Objective: In this study, the electrocardiographic and electrophysiologic characteristics of anteroseptal, midseptal, and posteroseptal APs were investigated in detail to elucidate unique electrical properties of APs in each location., Methods: From April 2002 to October 2006, a total of 120 patients with a septal AP-mediated tachycardia were enrolled in the study. A detailed examination including electrocardiographic analysis and electrophysiologic study was performed in all patients., Results: A total of 120 patients, including 98 patients with posteroseptal APs, 14 patients with anteroseptal APs, and 8 patients with midseptal APs, were studied. The anteroseptal APs could be differentiated from the midseptal APs by the 2 or more positive delta waves in inferior leads, whereas there is significant overlap in electrocardiographic features of midseptal and posteroseptal APs. The mean tachycardia cycle length was significantly shorter in patients with midseptal AP compared with those with anteroseptal and posteroseptal APs (284 +/- 49 ms vs 342 +/- 46 ms vs 350 +/- 68 ms, P = .03). The AH interval during tachycardia was also shorter in patients with midseptal APs (149 +/- 16 ms vs 200 +/- 51 ms vs 168 +/- 48 ms, P = .04). The patients with posteroseptal AP had a significantly higher incidence of atrial fibrillation (35%) than those with either midseptal (12%) or anteroseptal (14%) APs (P = .04). The patients with posteroseptal APs also had a significantly shorter antegrade effective refractory period of the AP (276 +/- 54 ms) than those with either midseptal (313 +/- 71 ms) or anteroseptal (325 +/- 61) APs (P = .036)., Conclusion: Electrocardiographic analysis is a reliable method for differentiation of the anteroseptal from the midseptal APs, whereas the same is not true for the midseptal and posteroseptal APs. Midseptal APs were characterized by faster orthodromic tachycardia, whereas posteroseptal APs had a higher inducibility of atrial fibrillation.

Background: Atrial fibrillation (AF) is the most common arrhythmia after coronary artery bypass graft (CABG) surgery. It has been shown that prophylactic oral beta-blocker administration reduces the incidence of post-CABG AF. However, the optimal beta-blocker has not been identified., Objective: This study sought to determine whether oral carvedilol (with its unique anti-inflammatory and antioxidant properties) is more effective than oral metoprolol for prevention of AF after CABG surgery., Methods: Between April 2006 and December 2006, 120 patients (63 men, mean age 61 +/- 9.4 years) who were scheduled to undergo their first on-pump CABG were enrolled in this study. The patients were randomized in a prospective 1:1 manner to receive either oral carvedilol (n = 60) or oral metoprolol (n = 60). The end point of the study was the occurrence of the new-onset AF during the first 5 days after CABG., Results: AF occurred in 29 of 120 patients (24.0%). The incidence of postoperative AF was 15.0% (9 of 60) in the carvedilol group and 33% (20 of 60) in the metoprolol group (P = .022). The carvedilol group was treated with mean daily dose of 46 +/- 9 mg and metoprolol group with mean daily dose of 93 +/- 11 mg. There were no differences between the study groups regarding any known preoperative, perioperative, or postoperative characteristics (all values were P >.05). No significant adverse effect was observed in either group., Conclusion: This prospective study suggested that oral carvedilol is more effective than oral metoprolol in the prevention of AF after on-pump CABG. It is well tolerated when started before and continued after the surgery. However, further prospective studies are needed to clarify this issue.

Background: Physiologic pacing is claimed to be superior to ventricular pacing in as much as it entails lower risk of atrial fibrillation, stroke, and atrial remodeling. There are few data on the relation between atrioventricular (AV) synchrony and atrial clot formation. Utilizing transesophageal echocardiography (TEE), this study sought to evaluate the effect of AV synchrony loss on left atrial physiology, atrial stasis, and clot formation., Methods: We conducted a cross-sectional study on patients with both AV and ventricular pacing with left ventricular ejection fraction (LVEF) >30%. TEE enabled us to explore atrial and pacing leads thrombi and measure left atrial appendage (LAA) flow velocity., Results: A total 72 patients (mean age, 65 +/- 11.7) were enrolled in the study. The pacing mode was VVI in 53% and AV sequential in 47% of patients. LVEF (mean +/- SD; %) was 53.3 +/- 6.2% in ventricular pacing mode and 52.2 +/- 6.6 in physiologic pacing mode. Thrombus formation on pacing lead (<10 mm in 97% of patients) was observed in 32% of all the patients (23% in patients with AV sequential pacing mode and 39% with VVI mode). Left atrial appendage flow velocity (LAA-FV) was significantly higher among the patients with AV sequential pacing mode (49.44 +/- 18 cm/s vs 40.94 +/- 19.4 cm/s, P value = 0.02). LAA-FV >40 cm/s was detected in 60% of the patients, 60% of whom were in physiologic mode. Left atrial size was significantly larger among the patients with VVI pacing mode (42.3 +/- 2.3 mm vs 37.79 +/- 4.5 mm, P = 0.001). Multivariate analysis showed no relation between LAA-FV and age, hypertension, diabetes mellitus, left atrial size, and left ventricular function. Only one patient had right atrial clot. There was no thrombus in the ventricles and atrial appendage., Conclusion: Long-term loss of AV synchrony induced by VVI pacing is associated with the impairment of LAA contraction. Thrombus formation in the LAA is not increased by VVI pacing in patients with relatively good left ventricular (LV) function and sinus rhythm.