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Background: Although catheter ablation techniques for atrial fibrillation (AF) have advanced, some cases of reconnections after pulmonary vein (PV) isolation still exist. The diversity of the anatomic wall thickness and fiber orientation around the PVs might contribute to reconnections., Objective: The purpose of this study was to investigate the utility of the emphasis map's emphasize settings to determine optimal ablation sites., Methods: Patients undergoing AF ablation with the EnSite X system who had PV reconnections were included. The emphasis map (a combination of peak frequency and local activation timing [LAT] maps) was created to obtain the emphasize settings for indicating the optimal ablation site (Emphasis group). In another group, the ablation site was determined based on LAT mapping (LAT group)., Results: A total of 64 patients (age 69 ± 9 years; 50 males), and 109 PVs were found to be reconnected and analyzed. Gaps were observed at 55 and 68 points of the PV isolation in the Emphasis and LAT groups, respectively. The number of ablation points needed to successfully eliminate the gaps, and the total energy were markedly smaller (1.6 ± 1.1 vs. 6.3 ± 3.7, P <.001; 3541 ± 2060 J vs 5606 ± 3728 J, P = .001) in the Emphasis group than in the LAT group, respectively. The average optimal emphasize setting was 338 ± 67 Hz in the Emphasis group., Conclusion: Adjusting the emphasize settings visualized the optimal ablation site, and the number of ablation points needed to reisolate the PV might be markedly reduced., Competing Interests: Disclosures The authors have no conflicts to disclose., (Copyright © 2024 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

Atrial fibrillation (AF) is the most common cardiac arrhythmia observed in the elderly. Its prevalence rises with age, particularly in individuals over 80 years old. While catheter ablation has emerged as a first line therapy for the patients with symptomatic AF, evidence on its application in elderly patients remains controversial. This study aimed to assess safety and efficacy outcomes of AF ablation in patients aged ≥ 80 years. Consecutive 1327 patients who underwent a first pulmonary vein isolation (PVI) for AF were retrospectively analyzed. Patients aged ≥ 80 years (elderly group, n = 107) were compared with patients aged < 80 years (younger group, n = 1220). At 1-year follow-up, there was no significant difference in AF free rate between the elderly and the younger group (72.0% vs. 73.9%, P = 0.786). Regarding major complications, the elderly patients had a greater incidence of periprocedural stroke (1.9% vs. 0.1%, P = 0.018). The rates of cardiac tamponade, phrenic palsy, and vascular complications were not significantly different between the 2 groups. PVI for AF is effective in patients aged ≥ 80 years with a similar success rate, but periprocedural stoke risk was higher compared to the younger population., (© 2024. Springer Nature Japan KK, part of Springer Nature.)

Introduction: Although catheter ablation (CA) of tachycardia-bradycardia syndrome (TBS) in patients with atrial fibrillation (AF) is considered to be an effective treatment strategy, pacemaker implantations (PMIs) are often required even after a successful CA. This study aimed to elucidate the clinical predictors of a PMI after CA., Methods: From 2011 to 2020, 103 consecutive patients diagnosed with TBS were retrospectively enrolled in the study. Among the 103 patients, 54 underwent a PMI and 49 CA of AF. During 47.4 ± 35.4 months after 1.4 ± 0.6 CA sessions, 37 (75.5%) of 49 patients were free from atrial arrhythmia recurrences. PMIs were performed in 11 patients (PMI group) and the remaining 38 did not receive a PMI (non-PMI group)., Results: When comparing the PMI and non-PMI groups, there were no differences in the basic mean heart rate (P = 0.36), maximum pauses detected by 24-hour Holter-monitoring (P = 0.61), and other clinical parameters between the two groups while the right atrial area index was larger (42.1 ± 24.0 vs. 21.8 ± 8.4 cm 2 /m 2 P = 0.002) in the PMI group than non-PMI group. The ROC curve analysis showed that the optimal cutoff point of the ratio of the right atrial area index to the left atrial area index for predicting a PMI following CA was 0.812 (Sensitivity 72.7%, specificity 71.1%, positive predictive value 42.1%, negative predictive value 90.0%, diagnostic accuracy 71.4%, AUC = 0.81)., Conclusion: Right atrial enlargement prior to CA was considered to be one of the risk factors for a PMI after CA of AF., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors. Published by Elsevier B.V.)

Background: The Kumamoto criteria have been proposed as a non-invasive screen for transthyretin amyloid cardiomyopathy. This study assessed the validity of the Kumamoto criteria externally. Methods and Results: The study included 138 patients (median age 73 years; 65% male) who underwent 99 m Tc-pyrophosphate (PYP) scintigraphy. Patients were divided into 4 groups according to total scores on the Kumamoto criteria (i.e., 0-3) for the following 3 factors: high-sensitivity cardiac troponin T ≥0.0308 ng/mL, wide (≥120 ms) QRS, and left ventricular posterior wall thickness ≥13.6 mm. The diagnostic performance and positive predictive value (PPV) of the Kumamoto criteria for positive 99 m Tc-PYP scintigraphy were validated. Eighteen (13%) patients were positive on 99 m Tc-PYP scintigraphy. The Kumamoto criteria had a favorable diagnostic performance (area under the curve 0.808). The PPV for groups with scores of 0, 1, 2, and 3 was 0% (n=0/42), 11% (n=6/57), 21% (n=7/33), and 83% (n=5/6), respectively, which is lower, particularly for those with a score of 2, than in the original Kumamoto cohort. However, the PPV increased after combining the Kumamoto criteria with a history of orthopedic diseases (spinal canal stenosis and/or carpal tunnel syndrome). Conclusions: This study suggests that the Kumamoto criteria have a favorable diagnostic performance; however, the PPV may decrease depending on the study population. Combining the Kumamoto criteria with the presence of orthopedic disease may improve the PPV., Competing Interests: W.S. is a member of Circulation Journal’s Editorial Team. E.K. is a member of Circulation Reports’ Editorial Team. The remaining authors have no conflicts of interest to declare., (Copyright © 2022, THE JAPANESE CIRCULATION SOCIETY.)

Atrial fibrillation (AF) is a common arrhythmia in patients with hypertrophic cardiomyopathy (HCM) and is associated with renal function deterioration. The protective effects of catheter ablation (CA) of AF on renal function in patients with HCM remain unsolved. From 2009 to 2020, a total of 169 consecutive patients with HCM and AF (age 70 ± 12, 87 males) were retrospectively evaluated. The estimated glomerular filtration rate (eGFR) was evaluated at the study enrollment or 1 month before the CA and reevaluated 3 and 12 months later. In the 169 patients, 63 underwent CA of AF (ablation group), and the remaining 106 did not (control group). After propensity score matching, 45 pairs were matched. The baseline eGFR was similar between the 2 groups (p = 0.83). During a mean follow-up period of 34 ± 27 months, sinus rhythm was maintained in 36 patients (80%) after 1.7 ± 0.8 ablation procedures. The eGFR significantly decreased from baseline to 3 months (p <0.01) and from baseline to 1 year (p <0.01) in the control group, whereas the eGFR in the ablation group was maintained both from baseline to 3 months (p = 0.94) and from baseline to 1 year (p = 1.00) after the CA. The change in the eGFR between baseline and 12 months was significantly smaller in the ablation group than in the control group (p <0.01). After logistic regression analysis, CA of AF was the independent predictor of an improvement of eGFR (odds ratio 2.81, 95% confidence interval 1.08 to 7.36, p = 0.04). In conclusion, CA of AF had a protective effect on renal function in patients with HCM., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Background: Atrial fibrillation (AF) is the most common arrhythmia in patients undergoing hemodialysis (HD); AF lowers quality of life (QoL) and increases the risk of dialysis-related complications. The present study aimed to evaluate the effectiveness of AF ablation on the QoL in patients undergoing HD., Methods: Nineteen patients undergoing HD (14 men, age 68 ± 8 years; 15 with paroxysmal AF) who underwent catheter ablation (CA) of AF were enrolled in the study. The Kidney Disease Quality of Life Short Form (KDQOL-SF) was assessed to evaluate the QoL of the HD patients at baseline and 6 months after the ablation. Ablation outcomes and procedural complications were evaluated and compared to those of 1053 consecutive non-HD patients who underwent AF ablation., Results: The KDQOL-SF of the HD patients 6 months after the ablation showed an improvement in physical functioning (54 ± 23 to 68 ± 28, P < 0.01), general health perceptions (38 ± 17 to 48 ± 15, P < 0.01), and symptoms/problems (75 ± 21 to 84 ± 13, P  = 0.02), compared to baseline. For intradialytic symptoms, dyspnea during HD significantly improved after the CA in the HD patients without AF recurrence (43% to 7%, P  = 0.04), whereas the atrial tachyarrhythmias and hypotension during HD remained unchanged. During the follow-up period of 17 ± 13 months after the last procedure, the incidence of being arrhythmia-free was similar (HD patients, 79% vs non-HD patients, 86%, log-rank P  = 0.82). No life-threatening complications occurred in any of the patients., Conclusions: CA of AF improves QoL in patients undergoing chronic HD therapy., (© 2022 The Authors.)

Purpose: Catheter ablation (CA) is an established treatment for atrial fibrillation (AF). Although coronary artery spasms (CAS) during or after ablation procedures have been described as a rare complication in some case reports, the incidence and characteristics of this complication have not been fully elucidated. The present observational study aimed to clarify the CAS in a large number of patients experiencing AF ablation., Methods: A total of 2913 consecutive patients (male: 78%, mean 66 ± 10 years) who underwent catheter ablation of AF were enrolled., Results: Nine patients (0.31%, mean 66 ± 10 years, 7 males) had transient ST-T elevation (STE). Eight out of the 9 patients had STE in the inferior leads. STE occurred after the transseptal puncture in 7 patients, after the sheath was pulled out of the left atrium in 1, and 2 h after the ablation procedure in 1. Six patients had definite angiographic CAS without any sign of an air embolization on the emergent coronary angiography. In the3 other patients, the STE improved either directly after an infusion of nitroglycerin or spontaneously before the CAG. The patients with CAS had a higher frequency of a smoking habit (89% vs. 53%; P = .04), smaller left atrial diameter (36 ± 6 vs. 40 ± 7; P = .07), and lower CHADS 2 score (0.6 ± 0.5 vs. 1.3 ± 1.1; P = .004) than those without., Conclusions: Although the incidence was rare (0.31%), CAS should be kept in mind as a potentially life-threatening complication throughout an AF ablation procedure especially performed under conscious sedation., (© 2021. The Author(s).)

Atrial fibrillation (AF) is the most common arrhythmia in patients with hypertrophic cardiomyopathy (HCM). The present study aimed to investigate the incidence and prognostic impact of newly detected AF after cardiac implantable electronic device (CIED) implantation with HCM patients. Fifty-six patients (33 men, age 57 ± 17 years) with HCM who underwent CIED implantations with no previous history of AF at the time of implantation (ICD n = 46, Pacemaker n = 10) were retrospectively enrolled. During 5.7 ± 3.6 years of follow-up, AF was newly detected in 20 (36%) of 56 patients after the CIED implantation (AF group) and the rest of the patients had no newly detected AF (non-AF group). The presence of mitral regurgitation (HR 8.49; 95% CI 2.29-30.6 P < 0.01) and concomitant NYHA II-IV (HR 3.37; 95% CI 1.30-8.86 P = 0.01) were the independent predictors of newly detected AF. During the follow-up, all patients in the AF group started anticoagulation mean 21 days after detection of AF, and none had a stroke during the follow-up period. The rate of appropriate ICD therapy (log-rank P = 0.95), inappropriate ICD therapy (log-rank P = 0.78), and all-cause death (log-rank P = 0.23) were similar between the two groups. However, the incidence of hospitalizations due to heart failure was higher in the AF group (55% vs. 6% log-rank P < 0.01). In conclusion, the incidence of newly detected AF after CIED implantations in HCM patients was high. The newly detected AF was associated with worsening heart failure and careful follow-up is recommended.

Pyrenocine A, a phytotoxin, was found to exhibit cytotoxicity against cancer cells with an IC 50 value of 2.6-12.9 μM. Live cell imaging analysis revealed that pyrenocine A arrested HeLa cells at the M phase with characteristic ring-shaped chromosomes. Furthermore, as a result of immunofluorescence staining analysis, we found that pyrenocine A resulted in the formation of monopolar spindles in HeLa cells. Monopolar spindles are known to be induced by inhibitors of the kinesin motor protein Eg5 such as monastrol and STLC. Monastrol and STLC induce monopolar spindle formation and M phase arrest via inhibition of the ATPase activity of Eg5. Interestingly, our data revealed that pyrenocine A had no effect on the ATPase activity of Eg5 in vitro, which suggested the compound induces a monopolar spindle by an unknown mechanism. Structure-activity relationship analysis indicates that the enone structure of pyrenocine A is likely to be important for its cytotoxicity. An alkyne-tagged analog of pyrenocine A was synthesized and suppressed proliferation of HeLa cells with an IC 50 value of 2.3 μM. We concluded that pyrenocine A induced monopolar spindle formation by a novel mechanism other than direct inhibition of Eg5 motor activity, and the activity of pyrenocine A may suggest a new anticancer mechanism., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

M cells are located in the follicle-associated epithelium (FAE) that covers Peyer's patches (PPs) and are responsible for the uptake of intestinal antigens. The differentiation of M cells is initiated by receptor activator of NF-κB. However, the intracellular pathways involved in M cell differentiation are still elusive. In this study, we demonstrate that the NF-κB pathway activated by RANK is essential for M cell differentiation using in vitro organoid culture. Overexpression of NF-κB transcription factors enhances the expression of M cell-associated molecules but is not sufficient to complete M cell differentiation. Furthermore, we evaluated the requirement for tumor necrosis factor receptor-associated factor 6 (TRAF6). Conditional deletion of TRAF6 in the intestinal epithelium causes a complete loss of M cells in PPs, resulting in impaired antigen uptake into PPs. In addition, the expression of FAE-associated genes is almost silenced in TRAF6-deficient mice. This study thus demonstrates the crucial role of TRAF6-mediated NF-κB signaling in the development of M cells and FAE., (© 2018 Kanaya et al.)

Mast cells are important for eradication of intestinal nematodes; however, their precise mechanisms of action have remained elusive, especially in the early phase of infection. We found that Spi-B-deficient mice had increased numbers of mast cells and rapidly expelled the Heligmosomoides polygyrus (Hp) nematode. This was accompanied by induction of interleukin-13 (IL-13)-producing group 2 innate lymphoid cells (ILC2) and goblet cell hyperplasia. Immediately after Hp infection, mast cells were rapidly activated to produce IL-33 in response to ATP released from apoptotic intestinal epithelial cells. In vivo inhibition of the P2X7 ATP receptor rendered the Spi-B-deficient mice susceptible to Hp, concomitant with elimination of mast cell activation and IL-13-producing ILC2 induction. These results uncover a previously unknown role for mast cells in innate immunity in that activation of mast cells by ATP orchestrates the development of a protective type 2 immune response, in part by producing IL-33, which contributes to ILC2 activation., (Copyright © 2017 Elsevier Inc. All rights reserved.)