Journal of Arrhythmia最新文献

Background

The widespread use of cardiac implantable electronic devices (CIEDs), combined with increasing global cremation rates, has raised concerns regarding potential explosion risks during cremation. Lithium batteries within these devices may rupture due to heat-induced internal pressure, potentially threatening crematorium infrastructure and staff safety. Despite these concerns, real-world data on explosion behavior and its consequences remain limited. This study aimed to assess the explosion characteristics of CIEDs during cremation and evaluate their impact on facility safety, with the goal of informing evidence-based guidelines.

Methods

Combustion experiments were performed using full-scale cremation furnaces set at 1100°C and 800°C. A total of 13 CIEDs (7 pacemakers and 6 implantable cardioverter-defibrillators) were tested, with synchronized audio-video monitoring. Additionally, nationwide survey data were collected from 2044 crematoria across Japan, focusing on cremation practices, reported damage, and staff injuries.

Results

All tested devices exploded, with mean ignition-to-explosion times of 4.3 ± 1.1 min at 1100°C and 5.4 ± 2.0 min at 800°C (p = 0.19). Seventeen explosion events were observed, yet no structural damage to the chambers occurred. Survey data revealed a decline in cremation refusal due to CIEDs—from 11.0% in 2012 to 4.6% in 2013 and 3.0% in 2014 (p < 0.001). According to respondents, this trend likely reflects an increased collaboration with medical associations, modernization of crematorium facilities, and dissemination of practical safety information.

Conclusions

Cremation of CIEDs without removal appears safe under modern, regulated facilities. However, region-specific guidelines remain necessary due to international variability in infrastructure and practices.

Background

Pulmonary vein isolation is a standard therapy for paroxysmal atrial fibrillation (AF). Pulsed field ablation (PFA) has emerged as a novel approach aiming to improve efficacy and safety over conventional thermal ablation (CTA) (radiofrequency and cryoballoon). This meta-analysis evaluated outcomes of PFA versus thermal ablation in paroxysmal AF.

Methods

Electronic databases were searched through May 2025 for randomized controlled trials (RCTs) and observational studies that compared the efficacy and safety of PFA versus CTA. The primary outcome was AF recurrence. Summary estimates were conducted using random effects.

Results

A total of six studies, involving 1928 patients, were included. The incidence of AF recurrence was significantly lower among patients treated with PFA (risk ratio [RR] 0.67; 95% confidence interval [CI] 0.53–0.85). PFA was associated with a lower incidence of any atrial arrhythmia recurrence (RR 0.78, 95% CI: 0.61–0.99). The total procedure duration was significantly shorter with PFA (mean difference −21.46 min (95% CI: −26.04 to −16.88)), but there was no difference in fluoroscopy time. The rates of esophageal injury and phrenic nerve palsy were lower with PFA. However, the data were limited for these two outcomes, and a meta-analysis was not conducted for them. There was no difference between the two groups in the incidence of stroke or pericardial tamponade.

Conclusion

Among patients with paroxysmal AF undergoing catheter ablation, PFA is associated with favorable outcomes, including lower recurrence and shorter procedure time compared to conventional ablation modalities.

Background

Amiodarone-induced pulmonary toxicity (APT) is one of the major side effects of the medication when used in the treatment of arrhythmia. However, the risk factors for developing APT have yet to be fully understood.

Methods and Results

We retrospectively analyzed 454 patients who were treated with amiodarone for arrhythmia between 2016 and 2020 at the National Cerebral and Cardiovascular Center, Osaka, Japan. During the median follow-up period of 207 days, 24 patients (5.4%) had APT. Using a multivariate analysis of the Cox proportional hazards model, lower body mass index (BMI) (hazard ratio [HR]: 0.81, 95% confidence interval [CI]: 0.71–0.95), higher age (HR: 1.06, 95% CI: 1.02–1.10), and higher amiodarone maintenance dose (HR: 1.01, 95% CI: 1.003–1.02) were risk factors for APT. Specifically, the patients whose BMIs were < 22 kg/m² were approximately three times more likely to develop APT than the patient whose BMIs were ≥ 22 kg/m². The cutoff value for maximum KL-6 levels during amiodarone therapy as an APT screening test was 444 U/mL or higher, with a sensitivity of 70.8% and specificity of 88.1%.

Conclusion

Lower BMI, higher age, and a higher maintenance dose were identified as independent risk factors for APT. KL-6 levels during administration may be useful in suspecting the development of APT.

Background

The efficacy of cryoballoon ablation (CBA) using a 28-mm or 31-mm cryoballoon for isolating the left common pulmonary vein (LCPV) remains poorly established. We aimed to evaluate procedural outcomes and long-term follow-up data of CBA for the LCPV using either POLARx with a fixed 28-mm cryoballoon or POLARx FIT with a size-adjustable 28-mm or 31-mm cryoballoon.

Methods

Patients with LCPV who underwent CBA for atrial fibrillation using POLARx or POLARx FIT between January 2022 and April 2024 were retrospectively analyzed. Procedural outcomes and long-term follow-up data were compared between the POLARx and POLARx FIT groups.

Results

Fifty-one patients (32 males [62.7%]; mean age, 66 ± 11.6 years) were analyzed. The POLARx group included 23 patients, and the POLARx FIT group included 28 patients. First-freeze pulmonary vein isolation (PVI) success was 1 (4.3%) versus 8 (28.6%) (p = 0.03), and radiofrequency touch-up ablation was required in 2 (8.7%) versus 0 patients (p = 0.2) in the POLARx and POLARx FIT groups, respectively. Nadir temperature was −53.6° ± 4.7°C versus −54.7° ± 5.6°C (p = 0.45); the number of applications was 3.2 ± 1 versus 2.3 ± 0.9 (p < 0.01); and total freezing time was 520.9 ± 164 s versus 377.7 ± 129.9 s (p < 0.01) for the POLARx and POLARx FIT groups, respectively. A single gastric hypomotility case was observed in the POLARx FIT group. The 1-year arrhythmia-free survival rates were 81.8% and 78.7% for the POLARx and POLARx FIT groups, respectively (p = 0.96).

Conclusions

POLARx FIT was useful for LCPV isolation, with a higher first-freeze PVI success rate, fewer applications, and shorter total freezing time compared to POLARx.

Background

Although immediate recurrence of atrial fibrillation (IRAF) after cardioversion has been proposed as a surrogate for atrial substrate vulnerability, its broad definition may insufficiently discriminate patients at highest risk of postablation recurrence. We introduced the concept of ultra-early recurrence of AF (URAF)—defined as recurrence within 10 s after direct current cardioversion (CV) under deep sedation—as a novel marker of advanced remodeling in persistent atrial fibrillation (AF).

Objective

To evaluate whether URAF independently predicts late recurrence following pulmonary vein isolation (PVI) in patients with persistent or long-standing persistent AF.

Methods

We retrospectively analyzed 104 patients undergoing first-time PVI for persistent AF. Among 93 patients who underwent external CV, URAF, and IRAF were defined as AF recurrence within 10 and 90 s, respectively. Recurrence of atrial arrhythmias was assessed at 12 m postablation.

Results

URAF was observed in 10/104 patients (9.6%) and was associated with higher 12-m recurrence compared with URAF-negative patients (50% vs. 18%, p = 0.02), whereas IRAF (20/104, 19.2%) showed no significant difference (30% vs. 19%, p = 0.28). On multivariable logistic regression, URAF (Odds Ratio (OR): 4.8; 95% Confidence Interval (CI): 1.16–19.98; p = 0.029) and long-standing AF (OR: 5.5; 95% CI: 1.70–17.78; p = 0.004) emerged as independent predictors of recurrence. Kaplan–Meier analysis showed worse recurrence-free survival for URAF (log-rank p = 0.02; HR 4.5, 95% CI 1.18–17.41).

Conclusion

URAF may represent a promising intra-procedural marker associated with post-ablation recurrence in persistent AF, but prospective validation in larger cohorts is required.

Background

Sodium-glucose co-transporter 2 (SGLT2) inhibitors have shown promise in reducing atrial fibrillation (AF) risk, but their mechanism of action in metabolic syndrome (MetS)-related AF remains unclear. This study aims to elucidate the potential mechanisms by which SGLT2 inhibitors interfere with AF initiation in MetS through comprehensive bioinformatic analysis.

Methods

A network pharmacology bioinformatic approach was employed to predict the molecular targets of SGLT2 inhibitors. Public databases, including SwissTarget, GeneCards, OMIM, and STRING, were utilized to identify and analyze targets associated with MetS-related AF. Protein–protein interaction (PPI) networks were constructed, followed by gene ontology (GO) and KEGG pathway enrichment analyses to elucidate the biological processes and pathways involved.

Results

A total of 52 common targets were identified linking SGLT2 inhibitors with MetS-related AF. The analysis highlighted the TNF-α and AGE-RAGE signaling pathways as key mechanisms through which SGLT2 inhibitors may mitigate AF. Our investigation identified p38 and JNK, components of the TNF-α signaling pathway, as primary targets in reducing atrial remodeling and fibrosis.

Conclusions

This study provides insights into the potential mechanisms by which SGLT2 inhibitors influence AF pathogenesis in MetS. The findings suggest that targeting the TNF-α signaling pathway may be a promising therapeutic strategy, with further experimental validation needed to confirm these results.

Trial Registration: The authors have nothing to report.

Background

Remote monitoring (RM) is crucial in managing patients with cardiac implantable electronic devices (CIED), and has been reported to improve clinical outcomes. The study's objective is to investigate whether compliance to RM has affected patients' long-term clinical outcomes.

Methods

This was a prospective single-center cohort study of consecutive patients on RM with an implantable cardioverter-defibrillator or cardiac resynchronization therapy defibrillator followed up from 2018 to 2024. For analysis, patients were stratified according to whether they were compliant with RM. Compliance was defined as having ≥ 2 scheduled transmissions per year. Outcomes studied were the combined endpoints of all-cause mortality or heart failure hospitalization.

Results

We analyzed 207 patients, of whom 58 (28.1%) were compliant and 149 (71.9%) were non-compliant. Baseline demographics were similar between both arms. We observed 6.9% (4/58) of compliant patients with all-cause mortality, compared to 15.4% (23/149) of non-compliant patients. Four percent (2/56) of compliant patients had a hospitalization for heart failure, compared to 12.2% (18/147) of non-compliant patients. The Kaplan–Meier analysis suggested differences in the mortality and heart failure hospitalization survival function for compliant versus non-compliant patients. Among 166 patients with available covariate data in the multivariable exponential accelerated failure time model, the time until mortality or heart failure hospitalization was longer for compliant compared to non-compliant patients (acceleration factor 0.24, 95% CI 0.07 to 0.81; p = 0.022).

Conclusion

RM compliance was associated with significantly lower combined end-points of all-cause mortality and heart failure hospitalizations, even though individual outcomes (mortality or HF hospitalization) did not reach statistical significance.

Background

The use of an insertable cardiac monitor (ICM) is recommended to help diagnose patients with unexplained syncope. Compared with conventional testing (CONV), ICM provides continuous long-term electrocardiogram (ECG) monitoring and has the ability to establish symptom-rhythm correlations, which is critical for patients with infrequent and randomized syncope. In China, the upfront cost of ICM is relatively high. However, the subsequent costs and outcomes of additional diagnostics and resulting treatments remain unclear. This study sought to evaluate the economic value of ICM versus CONV in patients with unexplained syncope and suspected of arrhythmia from the perspective of the China's healthcare system, aiming at informing clinical and policy decisions.

Methods

This study used a Markov model to assess the lifetime costs and benefits of ICM versus CONV for diagnosing syncope. In this model, the costs and effectiveness of all relevant diagnostic and follow-up arrhythmia-related treatments were considered. The study cohort characteristics and costs were obtained from a retrospective real-world study conducted in Sichuan Provincial People's Hospital. The mortality rate, syncope recurrence rate, syncope-related injury rate, and quality of life estimates were obtained from published literature. Total costs and quality-adjusted life years (QALYs) were modeled for two strategies, and the incremental cost-effectiveness ratio (ICER) was calculated. Three times China's GDP per capita in 2023 was used as a willingness-to-pay (WTP) threshold.

Results

ICM was predicted to be more expensive but more effective than CONV. The base-case results showed that the average cost of the ICM group was 111 733 CNY with QALYs of 10.28, while the average cost of the CONV group was 88 386 CNY with QALYs of 10.08. The ICER was calculated to be 115 596 CNY/QALY. With China's GDP per capita in 2023 being 89 358 CNY, the ICER was < 1.5 times the GDP per capita, and similar results were shown in the scenario analysis.

Conclusion

This analysis suggests that ICM is a cost-effective strategy, versus conventional testing, for the diagnosis of unexplained syncope in China, and supports wider uptake of the technology.

Background

While AV dyssynchrony is present in all cases with a single-chamber pacemaker, pacemaker syndrome (PMS) occurs in only a minority of patients. This study aims to investigate the role of physical activity in the incidence of this syndrome.

Method

Physical activity data of 200 patients receiving a dual-chamber pacemaker were obtained from the International Physical Activity Questionnaires. They were divided into two groups: Group A with a physical activity level of less than 500 MET-min/week, and Group B with a higher level. After switching to VVIR mode at discharge, patients were followed for 6 months to monitor the development of pacemaker syndrome.

Results

Forty-seven cases of PMS were recorded, representing an incidence rate of 23%. Group B had significantly more PMS cases than Group A (33 vs. 14, p = 0.002). There were no significant differences in the prevalence of coronary artery disease, chronic kidney disease, chronic obstructive pulmonary disease, and smoking between the two groups. However, hypertension and hypercholesterolemia were more prevalent in Group A. The receiver operating characteristic curve analysis revealed a cut-off value of 339 MET-min/week, with a sensitivity of 97.8% and a negative predictive value of 98% for predicting PMS occurrence. The area under the curve was 0.713 (p < 0.001, 95% CI: 0.65–0.77).

Conclusion

A physical activity level below 399 MET-min/week can predict the non-occurrence of PMS with a 98% predictive value. This can help physicians identify patients less likely to develop symptoms.