Background The increasing use of intracardiac echocardiography (ICE) in the ablation of premature ventricular complexes (PVCs) has raised questions about its true efficacy and safety. Objective To evaluate the long-term outcome and periprocedural complications of PVCs ablation with and without ICE. Methods This retrospective study collected the periprocedural complications and PVC burden post ablation. The risk factors of PVC recurrence was further explored. Results The study included patients treated without ICE (control group, n=451) and with ICE (ICE group, n=155) from May 2019 to July 2022. The ICE group demonstrated significantly lower fluoroscopy times and X-ray doses. There were no major complications in the ICE group, and the difference in the occurrence of periprocedural complications between the groups was not statistically significant (p=0.072). The long-term success rates were similar for the control and ICE groups (89.6% and 87.1%, respectively). The origin of PVCs was identified as the independent factor for ablation success. Conclusions The use of ICE did not confer an advantage with regard to long-term success in PVCs ablation. To thoroughly evaluate the safety and effectiveness of ICE in PVCs ablation, a prospective, multicenter, randomized study is warranted.

Background Previous research indicates disparities in atrial fibrillation (AF) recurrence and complications following catheter ablation in women; however, long-term outcomes based on gender remain underexplored. Objective This study evaluated the long-term rates of AF recurrence and major adverse cardiovascular and cerebrovascular events (MACCE) following catheter ablation, investigating gender-related risk factors to inform clinical practice improvement. Methods We conducted a retrospective analysis using data from a prospectively observational registry of AF ablation procedures at our institution from 2015 to 2020. Patients were followed up for MACCE and AF recurrence. The risk factors of AF recurrence and MACCE were further explored. Results The study cohort consisted of 2,293 patients, including 1,441 males and 852 females, and had an average follow-up duration of 50.36 months. After catheter ablation, females exhibited a notably higher rate of recurrence compared to males, with a hazard ratio of 1.305 and a 95% confidence interval ranging from 1.101 to 1.547, which was statistically significant (p=0.0014). Gender differences in AF recurrence persisted regardless of early versus late intervention (both p<0.05). No significant difference in MACCE rates was observed between genders. Independent risk factors for AF recurrence included female gender, diabetes, left atrial diameter ≥40 mm. Conclusions Gender differences significantly impact the long-term outcomes of AF recurrence, but not MACCE rates post-catheter ablation. The study highlights the necessity to integrate gender considerations into AF management strategies.

Background: Ivabradine (IVA) inhibits hyperpolarization-activated cyclic nucleotide channel to reduce pacing current with a possible increasing risk of atrial fibrillation (AF). Objective: To determine the effects of IVA on atrial action potentials, atrial arrhythmic activities and intracellular calcium homeostasis. Methods: Langendorff-perfused hearts and atrial myocytes from New Zealand White rabbits were used to record 12-lead ECGs，left atrial monophasic APs and Ca2+ sparks. Ca2+ handing related protein from left atrium were tested using western blotting. Results: IVA (0.1-10 μM) slowed the HR and prolonged the atrial MAPD90 (n=8, p<0.05) and induced atrial arrhythmias in 26% and 77% of hearts paced at cycle lengths of 350 ms and 570 ms, respectively (n=23 and 13, p<0.05). In hearts treated with either 0.3 µM acetylcholine (ACh) or 2 nM ATX-II with modulated atrial MAPDs, IVA (0.1-10 µM) caused either shortening or prolongation of MAPD90, respectively (n=18 and 21, p<0.05) and atrial arrhythmias in 61.9% and 44.4% of hearts (p<0.05). IVA induced delayed afterdepolarizations in 41.7%, 62.5% and 50% of cells in the absence and presence of either ATX-II or ACh, respectively (n=12, 8 and 8, p<0.05). IVA (0.03-3 μM) increased the frequency, amplitude and full width at half-maximum (n=22, p<0.05), and the expression of ryanodine receptor and Na+/Ca2+ exchanger with decreased sarcoplasmic reticulum calcium pump (n=4-5, p<0.05). Conclusion: IVA caused a blunted HR reduction and increased atrial proarrhythmic risk in hearts with slow rate, enhanced vagal tone and late INa, and DADs resulting from enhanced Ca2+ release.

Objective: The present paper is to determine the effects and underlying mechanisms of ivabradine (IVA) on atrial fibrillation (AF). Methods: Electrophysiological changes were determined using Langendorff-perfused hearts and patch-clamp techniques. Parameters of Ca2+ handling were evaluated by using calcium imaging and western blotting. Results: IVA (0.1-10 μM) slowed HR in a concentration-dependent manner in isolated hearts of rabbit. IVA induced atrial arrhythmias in 26.1% and 76.9% of hearts paced at a basic cycle length of 350 and 570 ms, respectively. In hearts pretreated with either acetylcholine (ACh) or anemone toxin-II (ATX-II) which caused no inducible atrial arrhythmias, adding to IVA administration caused atrial arrhythmias in 61.9% (13/21) and 44.4% (8/18) of hearts, respectively. In atrial myocytes, IVA induced DADs by 41.7%, 62.5% and 50.0%, respectively, in the absence and presence of either ACh or ATX-II. IVA increased the frequency, amplitude and full width at half-maximum (FWHM) of Ca2+ sparks and decreased Ca2+ transport in association with increased protein expression of RyR2 and NCX1 and decreased SERCA2. Conclusion: IVA increases atrial proarrhythmic risk in hearts with a slow HR, enhanced vagal tone and increased late sodium current by inducing DADs resulting from an enhanced intracellular Ca2+ inhomeostasis.

Aims: To assess the effect of oral anticoagulant (OAC) administration on incidence of dementia in patients with atrial fibrillation (AF) with Systematic review and meta-analysis in according with the Preferred Reporting Items for Systematic Review and Meta-analysis Protocols. Methods: We systematically searched the electronic databases including Pubmed, Embase, Cochrane library, and ClinicalTrails.gov for relevant articles. The primary outcome was the incidence of dementia. The adjusted risk ratio (RR), odds ratio, or hazard ratio were extracted and pooled by the random-effects models. Subgroup analysis was performed according to the setting observational window. Risk of bias was assessed using the Newcastle-Ottawa Scale, while publication bias was assessed by the Begg’s and Egger’s tests. Results: Nine studies included in this review (2 prospective and 7 retrospective observational studies, including 613,920 patients). The results presented the significant association between OAC therapy and the reduced risk of dementia compared with no treatment (RR [95%CI] =0.72 [0.60, 0.86], I2=97.2%; P =0.000). In the subgroup analysis, the pooled RR became statistically non-significant (including four studies, RR [95%CI] =0.75 [0.51, 1.10], I2=98.8%; P =0.000). There is no significant risk of bias and publication bias. Conclusions: This study indicated the protective effect of OAC therapy for dementia in patients with AF. However, the results are limited because of high heterogeneity, inconsistent direction of effect in subgroup analysis. Further prospective well-designed study is needed with longer follow-up duration in younger patients.