BACKGROUND AND AIMS:Posterior papillary muscle (PPM) and false tendons (FTs) in the right ventricle (RV) may act as a potential source of ventricular arrhythmias(VAs). We aimed to systematically describe the electrophysiological characteristics and the outcome of radiofrequency catheter ablation (RFCA) of VAs originating from the RV PPM -FT complex. METHODS:From a total of 2184 patients with VAs who underwent catheter ablation, 12 patients (0.55%) with VAs associated with RV PPM-FTs complex were enrolled in the study. Activation mapping and pace mapping were performed to localize the origin of VAs. Intracardiac echocardiography (ICE) was used in all patients to directly visualize the PPM and the FTs. We chose 12 patients with VAs originating from the RV moderate band (MB) as the control group. CONCLUSIONS:In contrast to the MB group, the QRS duration, the R wave duration and the RS interval of lead V1 of the study group was longer. The negative component in inferior leads (II, III, aVF) of the study group was deeper than the MB group. The PVCs in the study group were successfully eliminated by ablation in all patients. The target sites were confirmed to be related to the RV PPM and FTs complex. A pre-systolic potential was observed preceding local ventricular activation in seven patients.

ABSTRACT We report a case of a 41‐year‐old man with recurrent nocturnal ventricular asystole secondary to advanced atrioventricular (AV) block, which was successfully treated with ganglionated plexus (GP) ablation based on the presumption of excessive vagal tone. This approach may offer a potential alternative for vagally mediated nocturnal AV block in selected young patients who decline pacemaker implantation.

Importance Success rates of pulmonary vein isolation (PVI) are modest for persistent atrial fibrillation (AF). Additional linear ablation beyond PVI has not been proved superior to PVI alone in randomized trials. Ethanol infusion of the vein of Marshall (EIVOM) facilitates ablation at the mitral isthmus and may lead to improved effectiveness of a linear ablation strategy. Objective To determine whether linear ablation with radiofrequency energy combined with EIVOM added to PVI improves sinus rhythm maintenance compared with PVI alone in patients with persistent AF. Design, Setting, and Participants The PROMPT-AF trial is an investigator-initiated, multicenter, open-label, randomized trial involving 12 tertiary hospitals in China. A total of 498 patients aged 18 to 80 years, with AF persisting for more than 3 months, undergoing first-time AF ablation, were enrolled and randomized from August 27, 2021, to July 16, 2023. Interventions Patients were randomized to undergo PVI alone or PVI plus EIVOM and linear ablation (intervention). The latter group first underwent EIVOM, followed by PVI and linear ablation of the left atrial roof, mitral isthmus, and cavotricuspid isthmus. Main Outcomes and Measures The primary end point was freedom from any documented atrial arrhythmias lasting more than 30 seconds, without the use of antiarrhythmic drugs within 12 months. Secondary outcomes included freedom from atrial arrhythmia recurrence, AF, atrial arrhythmia recurrence after multiple procedures, and documented atrial tachycardia or atrial flutter with or without antiarrhythmic drugs; AF burden; and improvement in quality of life. Patients were monitored with wearable single-lead electrocardiographic (ECG) patches, worn for 24 hours a week, supplemented by symptom-triggered ECGs and Holter monitoring. Results Among 498 randomized patients, 495 (99.4%) were included in the primary analysis (mean age, 61.1 years [SD, 9.7] years, 361 male [72.9%]). After 12 months, 174 of 246 patients (70.7%) assigned to undergo PVI plus EIVOM and linear ablation and 153 of 249 patients (61.5%) assigned to undergo PVI alone remained free from atrial arrhythmias without taking antiarrhythmic drugs (hazard ratio, 0.73; 95% CI, 0.54-0.99, P = .045). The intervention effect was consistent across all prespecified subgroups. The comparison of secondary outcomes did not demonstrate significant results. Conclusion Among patients with persistent AF, linear ablation combined with EIVOM in addition to PVI significantly improved freedom from atrial arrhythmias within 12 months compared with PVI alone.

BACKGROUND:The circuit of scar-related upper loop macroreentry atrial flutter (AFL) surrounding the superior vena cava (SVC) has been described by prior case reports. However, the correlation between the circuit and arrhythmogenic substrates and the corresponding optimized ablation strategy need to be further investigated. OBJECTIVE:We aimed to identify the electrophysiologic substrate and corresponding ablation strategies of SVC-AFL using high-resolution mapping. METHODS:From June 1, 2017, to May 1, 2023, consecutive patients with macroreentrant atrial tachycardias (ATs) from 7 institutions were retrospectively evaluated. Patients with SVC-AFL were enrolled and analyzed. RESULTS:Of 1282 patients with macroreentrant ATs, 16 patients (1.2%; median age, 60.9 years; 8 male) had SVC-AFL (mean cycle length, 281.0 ± 55.1 ms), all identified during high-resolution activation mapping. All patients had prior cardiac surgery (14 [87.5%]) or catheter ablation (8 [50.0%]). A longitudinal surgical incision/scar extending from the SVC to the right atrium was observed in all patients, enabling macroreentry. SVC-AFLs with shorter circuits (<180 mm) had more slow conduction areas than those with longer circuits (>180 mm; 3.0 [2.0-4.0] vs 1.0 [1.0-1.5]; P = .023]. All ATs were terminated by ablating the channel between the surgical incision/scar and anatomic barriers. Cavotricuspid isthmus block was achieved in all patients. During a 21-month follow-up, all patients were free of atrial arrhythmias except for 4 patients experiencing short-lived paroxysmal ATs that did not require further ablation. CONCLUSION:A surgical incision/scar extending from the SVC to right atrium promotes the development of SVC-AFL. Substrate-based linear lesions along with prophylactic cavotricuspid isthmus ablation afford favorable clinical outcomes.

BackgroundAtrial fibrillation (AF) exhibits gender disparities in prevalence, complications, pharmacological management, and ablation efficacy. Ethanol infusion of the vein of Marshall (EIVOM) is promising for enhancing AF ablation success rate, yet sex differences of EIVOM are lacking evidence.MethodThis was a non-randomized, single-center, retrospective observational study. Patients with AF received stepwise ablations composed of EIVOM, pulmonary vein isolation, and linear ablation. The primary endpoint was defined as the recurrence of atrial tachycardia over 30 s. Propensity score matching (PSM) was performed to reduce selection bias.ResultsFrom April 2020 to May 2022, 432 patients were included, comprising 288 male patients and 144 female patients. Compared with the male patients, the female patients were older, with worse heart function class. EIVOM success rate was significantly lower in the female patients compared with the male patients (86.1% vs. 93.4%). No significant differences in major procedural complications were observed between the male and female patients. During a median follow-up of 12 months, the female patients had significantly higher AF recurrence. Multivariate Cox regression analysis showed that female sex, body mass index <21.62, left atrial diameter >47 mm, and complex fractionated atrial electrogram ablation are independent risk factors for AF recurrence. After PSM, the AF recurrence rate remained statistically higher in the female patients compared with the male patients.ConclusionCompared with the male patients, the female patients were older, more symptomatic, and had worse heart function. The female patients had significantly higher AF recurrence after EIVOM combined with catheter ablation.

ImportanceSuccess rates of pulmonary vein isolation (PVI) are modest for persistent atrial fibrillation (AF). Additional linear ablation beyond PVI has not been proved superior to PVI alone in randomized trials. Ethanol infusion of the vein of Marshall (EIVOM) facilitates ablation at the mitral isthmus and may lead to improved effectiveness of a linear ablation strategy.ObjectiveTo determine whether linear ablation with radiofrequency energy combined with EIVOM added to PVI improves sinus rhythm maintenance compared with PVI alone in patients with persistent AF.Design, Setting, and ParticipantsThe PROMPT-AF trial is an investigator-initiated, multicenter, open-label, randomized trial involving 12 tertiary hospitals in China. A total of 498 patients aged 18 to 80 years, with AF persisting for more than 3 months, undergoing first-time AF ablation, were enrolled and randomized from August 27, 2021, to July 16, 2023.InterventionsPatients were randomized to undergo PVI alone or PVI plus EIVOM and linear ablation (intervention). The latter group first underwent EIVOM, followed by PVI and linear ablation of the left atrial roof, mitral isthmus, and cavotricuspid isthmus.Main Outcomes and MeasuresThe primary end point was freedom from any documented atrial arrhythmias lasting more than 30 seconds, without the use of antiarrhythmic drugs within 12 months. Secondary outcomes included freedom from atrial arrhythmia recurrence, AF, atrial arrhythmia recurrence after multiple procedures, and documented atrial tachycardia or atrial flutter with or without antiarrhythmic drugs; AF burden; and improvement in quality of life. Patients were monitored with wearable single-lead electrocardiographic (ECG) patches, worn for 24 hours a week, supplemented by symptom-triggered ECGs and Holter monitoring.ResultsAmong 498 randomized patients, 495 (99.4%) were included in the primary analysis (mean age, 61.1 years [SD, 9.7] years, 361 male [72.9%]). After 12 months, 174 of 246 patients (70.7%) assigned to undergo PVI plus EIVOM and linear ablation and 153 of 249 patients (61.5%) assigned to undergo PVI alone remained free from atrial arrhythmias without taking antiarrhythmic drugs (hazard ratio, 0.73; 95% CI, 0.54-0.99, P = .045). The intervention effect was consistent across all prespecified subgroups. The comparison of secondary outcomes did not demonstrate significant results.ConclusionAmong patients with persistent AF, linear ablation combined with EIVOM in addition to PVI significantly improved freedom from atrial arrhythmias within 12 months compared with PVI alone.Trial RegistrationClinicalTrials.gov Identifier: NCT04497376

Left atrial (LA) enlargement is a widely recognized factor that increases the risk of ablation failure in patients with atrial fibrillation (AF). This retrospective, observational study aimed to assess the influence of vein of Marshall (VOM) ethanol infusion (VOM-EI) on persistent atrial fibrillation (PsAF) ablation among patients with severe LA enlargement. In this research, 178 patients underwent the VOM-EI followed by the radiofrequency (RF) ablation procedure, which was based on circumferential pulmonary vein antrum (CPVA) ablation and linear ablation of the roof of the LA and the mitral isthmus (MI). In comparison, 83 patients only underwent the RF ablation procedure. In the VOM + RF ablation group, the duration of left CPVA ablation was shorter compared to the RF ablation group (20.3 ± 8.7 minutes vs. 27.1 ± 8.1 minutes, P < 0.0001). The rate of MI block was higher (94.9% vs. 85.5%, P = 0.01) in the VOM + RF ablation group, with a shorter MI ablation time (23.2 ± 10.8 minutes vs. 30.5 ± 11.8 minutes, P < 0.0001), and a lower need for coronary sinus vein ablation compared to the RF ablation group (64.0% vs. 78.3%, P = 0.02). Throughout the one-year observation period, the VOM + RF ablation group exhibited a notably superior survival rate without recurrence compared to the RF ablation group (78.7% vs. 65.1%, P = 0.02). As compared to the RF ablation group, the VOM + RF ablation group had a lower rate of recurrence with atrial tachycardia (8.4% vs. 19.3%, P = 0.01). The VOM-EI facilitated the left CPVA and the MI ablation and improved the ablation outcomes in patients with severe LA enlargement for treating PsAF.

BACKGROUND Epicardial Marshall bundles (MBs) are frequently used in left atrial tachycardias (LATs) after atrial fibrillation (AF) ablation with pulmonary vein isolation and substrate modification. OBJECTIVE This study sought to classify different activation patterns of MB-mediated LATs and the corresponding electrophysiologic characteristics. METHODS From 2019 to 2021, 28 cases of atrial tachycardias after AF ablation were diagnosed as MB-mediated LATs by ultrahigh-density mapping and entrainment. Cannulation and mapping in the vein of Marshall (VOM) and epicardial mapping in the MB region were also performed in selected cases to further prove the mechanism. RESULTS Three activation patterns were identified with a critical isthmus through the MB: perimitral macroreentry (perimitral LAT; n = 20 [71.4%]); left atrial appendage-related reentry (n = 5 [17.9%]); and left pulmonary vein-related reentry (n = 3 [10.7%]). In 18 patients, a characteristic triple potential observed along the previously endocardial left atrial ridge block line was composed of near-field double potentials and far-field MB potential. These findings were further delineated in 24 patients with either cannulation in the VOM (19 patients) or epicardial mapping (5 patients). Ethanol infusion of the VOM resulted in atrial tachycardia termination in 20 of 28 patients. CONCLUSION Different types of MB-mediated LATs after AF ablation could be identified by ultrahigh-density mapping. Ethanol infusion within the VOM was effective in eliminating these tachycardias.

BACKGROUND Different types of recurrent atrial tachycardia (AT) after Cox-maze procedures have been reported, whereas biatrial tachycardia (BiAT) has not been systematically analyzed. OBJECTIVE In this study, we retrospectively investigated the electrophysiologic characteristics of BiAT after Cox-maze procedures by use of an ultrahigh-density mapping system. METHODS Of a consecutive 76 patients who underwent catheter ablation of AT after Cox-maze procedures, 12 BiATs were identified. High-density activation mapping was performed in both the left atrium and right atrium in combination with entrainment pacing to confirm the circuit. RESULTS We classified these BiATs into 2 groups. In group 1 (7 patients), the bidirectional block of maze linear lesions to prevent the macroreentrant AT was achieved; the posterior interatrial connections were involved in the circuit. In group 2 (5 patients), the bidirectional block of maze linear lesions was not blocked, and the most common gap was located at the end of the linear lesion near the annulus. In group 1, all the ATs were terminated by targeting the corresponding left atrium end of the posterior interatrial connections. In group 2, the ATs were terminated by targeting the gap near the annulus. CONCLUSION The optimal ablation strategy for BiATs after the maze procedure should be based on detailed demonstration of the circuit by high-density mapping.

BackgroundIn medical practice, atrial fibrillation (AF) is intricately associated with heart failure (HF). Currently, ethanol infusion of vein of Marshall (EIVOM) for AF ablation in HF patients remains significantly limited.MethodThis was a non-randomized, single-center, retrospective observational study. AF patients received 4-step ablation composed of EIVOM, pulmonary vein isolation (PVI) and linear ablation. The primary composite endpoint was defined as recurrence of atrial tachycardia over 30 s. Propensity score matching (PSM) was performed to reduce selection bias.ResultsFrom April 2020 to May 2022, 362 patients were included, comprising of 182 HF patients and 180 non-HF patients. EIVOM success rate was lower in HF patients than non-HF patients (86.8% vs. 93.9%). Cardiac effusion was more common in HF patients (44.0% vs. 37.2%), and 2 cases of atrial-esophageal fistula were observed in the HF group. During a median follow-up of 12 months, no significant difference in the primary endpoint was observed between HF and non-HF group. Different HF subgroups had similar AF recurrence. After PSM, AF recurrence rate remained statistically equivalent between the HF and non-HF groups.ConclusionEVIOM combining catheter ablation can be completed with comparable success rate in AF patients with or without HF. However, peri-procedural safety is a concern for HF patients undergoing EIVOM combing AF catheter ablation. During the follow-up, HF status before ablation is not related with increased AF recurrence.

Background: An electrical storm due to malignant ventricular tachycardia (VT) is a life-threatening condition that requires catheter ablation (CA). Most VT arrhythmias evolve over time after acute myocardial infarction, coronary artery bypass grafting, or chronic heart failure. Clinically, only radiofrequency ablation can identify and block all arrhythmia origin points. The procedure necessitates continuous VT induction in patients, resulting in hemodynamic instability; therefore, extracorporeal membrane oxygenation (ECMO) support is required. Earlier studies have reported substantial mortality rates; however, our results are significantly more favorable. In this study, we combined the minimally invasive extracorporeal circulation (MiECC) approach with ECMO to preserve an appropriate ECMO flow rate, thus reducing intraoperative left heart afterload. We report 21 cases illustrating the usefulness of modified veno-arterial (VA)-ECMO in this scenario. Methods: Data of 21 patients supported by the modified VA-ECMO system (MiECC approach combined with the ECMO system) during VT CA in the Wuhan Asia Heart Hospital between June 2020 and July 2021 were reviewed retrospectively. Results: Successful ablation was achieved in 20 out of 21 patients (95%). The median time for ECMO implantation was 206 min. Only two patients experienced complications post-treatment. All patients made complete recovery and were discharged. All patients were alive at the 1-year-follow-up. Conclusions: Our modified VA-ECMO system helped restore systemic circulation in patients experiencing an electrical storm, thus achieving greater electrical stability during VT CA. Pre-insertion of VA-ECMO can achieve even better results.

Background:Single-ring isolation (SRI) of the pulmonary veins and the left atrial post wall (LAPW) is an accepted strategy in atrial fibrillation ablation. Whether SRI combined with superior vena cava isolation (SVCI) could further increase the success rate of paroxysmal atrial fibrillation (PAF) has not been reported.Objective:This study aimed to investigate whether SRI combined with SVCI was feasible and whether it could improve the success rate of PAF ablation.Methods and results:In our study, sixty patients with PAF from May 2019 to March 2021 were included. SRI plus SVCI was completed with ablation index (AI)-guided high-power ablation. The success rates of SRI and SVCI were 100% and 97%, respectively. One-pass SRI was achieved in 41 out of 60 patients, with 19 out of 60 patients requiring additional ablation to complete the SRI. SVC was not isolated in 2 out of the 60 cases due to concerns about the phrenic nerve (PN) injury. Among the enrolled patients, 2 patients had anomalous pulmonary veins (PVs) (common ostium of inferior PVs). SRI was applied to achieve the PV and PW isolation. After ablation, one patient had an ischemic stroke but recovered without severe morbidity. The average follow-up period was (20 ± 7) months, and single-procedure freedom from atrial arrhythmia was 91.7%. AT/AF recurred in five patients, and 2 out of 5 patients underwent redo ablation. The multi-procedure freedom from atrial arrhythmia was 95%.Conclusion:Our novel ablation strategy, SRI combined with SVCI, in patients with PAF was feasible and safe, with a relatively high success rate.

Background: For patients with persistent atrial fibrillation (AF), whether linear ablation should be performed remains controversial, and the efficacy and safety for ablation index (AI)-guided high-energy linear ablation of mitral isthmus (MI) and left atrial (LA) posterior box isolation is still unclear. The aims of this study were to assess the feasibility and clinical success rate of pulmonary veins isolation (PVI) combined with linear ablation of LA roof and posterior inferior (posterior wall isolation) and MI compare with the PVI-alone method in patients of persistent AF. Methods and results: 362 consecutive persistent AF patients were enrolled from two electrophysiology centers. A total of 200 cases were in PVI-plus group and 162 cases were in PVI-alone group. The PVI-alone group received wide circumferential isolation of both ipsilateral pulmonary veins. PVI combined with linear ablation of left atrial posterior wall isolation (LAPWI)and MI were performed in the PVI-plus group. The primary study end point was the first recurrence of an atrial arrhythmia. After 24 months, freedom from the primary endpoint was achieved in 73.5% of the patients in the PVI-plus group and 62.5% in the PVI-alone group (hazard ratio = 0.62, 95% confidence interval: 0.43–0.91, log rank p = 0.012). The procedure-related complication rates were 2.5% in PVI-plus group and 1.9% in PVI-alone group (p = 0.808). Conclusion: In this study, the ablation strategy of ablation (PVI plus linear ablation of mitral isthmus and posterior box isolation) was feasible and safe for persistent AF patients. Compared with the PVI-alone method, it improved outcomes in patients with persistent AF.

Background In randomized studies, the strategy of pulmonary vein antral isolation (PVI) plus linear ablation has failed to increase success rates for persistent atrial fibrillation (PeAF) ablation when compared with PVI alone. Peri-mitral reentry related atrial tachycardia due to incomplete linear block is an important cause of clinical failures of a first ablation procedure. Ethanol infusion (EI) into the vein of Marshall (EI-VOM) has been demonstrated to facilitate a durable mitral isthmus linear lesion.Objective This trial is designed to compare arrhythmia-free survival between PVI and an ablation strategy termed upgraded '2C3L' for the ablation of PeAF.Study Design The PROMPT-AF study (clinicaltrials.gov 04497376) is a prospective, multicenter, open-label, random-ized trial using a 1:1 parallel-control approach. Patients ( n = 498) undergoing their first catheter ablation of PeAF will be randomized to either the upgraded '2C3L' arm or PVI arm in a 1:1 fashion. The upgraded '2C3L' technique is a fixed abla-tion approach consisting of EI-VOM, bilateral circumferential PVI, and 3 linear ablation lesion sets across the mitral isthmus, left atrial roof, and cavotricuspid isthmus. The follow-up duration is 12 months. The primary end point is freedom from atrial arrhythmias of > 30 seconds, without antiarrhythmic drugs, in 12 months after the index ablation procedure (excluding a blanking period of 3 months).Conclusions The PROMPT-AF study will evaluate the efficacy of the fixed '2C3L' approach in conjunction with EI-VOM, compared with PVI alone, in patients with PeAF undergoing de novo ablation. (Am Heart J 2023;260:34-43.)

目的 总结非手术疤痕相关的右房房性心动过速(简称房速)在超高密度标测下的电生理特点及消融经验.方法 回顾分析武汉亚洲心脏病医院及北京大学第一医院两所机构中使用 Rhythmia超高密度标测系统进行右房房速导管消融治疗的 134 例患者,选择既往无心脏手术史的非手术瘢痕相关右房房速患者作为研究对象.通过超高密度标测系统研究其电生理折返机制.结果 18 例患者入选,其中 13 例为持续性房速,5 例为阵发性房速.在手术过程中,共观察到 52 种不同的房速,平均每例患者(3.2±1.5)个房速,心动过速周长为(264.7±32.5)ms.大多数患者在标测或消融过程中,房速很容易转化为具有不同心动过速周长和 P 波形态的另一种房速.最终,完成 45 个房速的标测图.分析这些激动标测图,发现非手术疤痕相关的右房房速可分为 6 型.致密疤痕的不同位置和延伸与房速的折返机制有关.结论 使用超高密度标测系统能显示非手术瘢痕相关右房房速的折返环路,并提供了相应的消融策略.

BACKGROUND:Endocardial ablation is effective for most focal atrial tachycardias (FATs). In rare circumstances, the FAT can originate from the epicardial side of the atrium.OBJECTIVE:In the present study, we retrospectively assessed the percutaneous approach for epicardial ablation of FAT when standard endocardial ablation had failed.METHODS:Among a consecutive 186 patients undergoing ablation for 198 FATs, epicardial mapping and ablation via a percutaneous subxiphoid approach were attempted in 10 patients because of failed endocardial ablation.RESULTS:In 3 cases, the origin of FAT was at the epicardial side of the junction of the right atrial appendage and superior vena cava. In 3 cases, the origin of FAT was located in the epicardial region of the left atrial insertion of Bachmann bundle. In 2 cases, the FAT originated from the epicardial side of the right atrial free wall. In 1 case, the FAT was successfully ablated from the epicardial side of the right atrial appendage, and in the remaining case, the origin of FAT was located in the epicardial region of the vein of Marshall. All FATs were successfully eliminated by ablation at the epicardial earliest activation site.CONCLUSION:Epicardial mapping and ablation can be considered as an effective and safe option for FAT resistant to endocardial ablation.

BackgroundIncreasing age is a significant risk factor for atrial fibrillation (AF) recurrence after catheter ablation (CA). We accomplished this study to evaluate the efficacy and safety of the vein of Marshall (VOM) ethanol infusion (VOM-EI) with CA in elderly patients with persistent AF (PsAF).MethodsThis retrospective observational study included 360 consecutive adult patients with PsAF, of which 141 were in the Elder group (age ≥65 years) and 219 were in the Younger group (age <65 years), who underwent the VOM-EI and radiofrequency CA (RFCA) between May 2020 and April 2022. The efficacy endpoint was no recurrence of AF within one year after CA.ResultsThe VOM-EI was successfully performed in 90.8% of patients from the Elder and 88.6% from the Younger group. All patients achieved PVI; 97.9% of patients from the Elder and 98.6% from the Younger group reached LA roof block, and 93.6% of patients from the Elder and 95.9% from the Younger group achieved MI block. There was no significant difference in 1-year survival without recurrence of AF between the two groups (83.0% and 84.5%, respectively). The incidence of complications within 30 days after the procedure from the two groups was low and did not differ significantly.ConclusionThe VOM-EI combined with RFCA proved to be an effective and safe strategy for treating PsAF in elderly and younger patients.

Mapping and ablation of atrial tachycardia (AT) in patients who have had prior cardiac surgery can be a challenge for clinical electrophysiologists. High density mapping (HDM) technology has been widely used in these patients because it provides a better characterization of the substrate and the mechanisms with an unprecedented high resolution. In this review, we summarize how the latest HDM technologies can reveal the mechanism of AT in different types of patients post‐cardiac surgery and guide a specifically tailored ablation strategy.