Search

Introduction: Pulsed‐field ablation (PFA) is a novel nonthermal energy that shows unique features that can be of use beyond pulmonary vein ablation, like tissue selectivity or proximity rather than contact dependency. Methods and Results: We report three cases of right focal atrial tachycardias arising from the superior cavoatrial junction and the crista terminalis, in close relationship with the phrenic nerve, effectively ablated using a commercially available PFA catheter designed for pulmonary vein isolation without collateral damage. Conclusion: PFA can be useful for treating right atrial tachycardias involving sites near the phrenic nerve, avoiding the need for complex nerve‐sparing strategies. [ABSTRACT FROM AUTHOR]

Background An atrioventricular node (AVN) ablation and permanent pacing have been previously reported as effective treatments for patients with atrial tachyarrhythmias. However single-ventricle patients requiring chronic ventricular pacing are at a higher risk of developing ventricular dysfunction and atrioventricular valve regurgitation. We report a case of successful AVN ablation in a 3-month-old infant with hypoplastic left heart syndrome and ectopic atrial tachycardia (EAT). Case summary A boy with hypoplastic left heart syndrome who had a refractory EAT resistant to various medications. At 2 months old, we performed an urgent radiofrequency (RF) catheter ablation of the EAT and the applications delivered at the cavo-atrial junction. Although it disappeared after the first catheter ablation for 2 weeks, it recurred on the next day after the diaphragm plication. At 3 months old and weighed 3.1 kg, we decided to perform an urgent AVN ablation of the EAT. The application was performed on the mid-septum of the tricuspid septum. A permanent pacemaker was implanted after the ablation. After the AVN ablation, the haemodynamics stabilized during the EAT. However, he died from a bacteraemia infection at 4 months. Discussion This patient received an AVN ablation due to failure to previous RF catheter ablation and was haemodynamically stable with the dual-chamber pacemaker. The AV block was successfully created by RF energy on the mid-septum of the tricuspid annulus in this hypoplastic left heart syndrome patient. Pathological findings exhibited that the compact AVN was totally ablated without damage to the tricuspid leaflets or coronary artery. [ABSTRACT FROM AUTHOR]

Aims Pulsed-field ablation (PFA) is an emerging technology to perform pulmonary vein isolation (PVI). Initial data demonstrated high safety and efficacy. Data on long-term PVI durability and reconduction patterns in comparison to established energy sources for PVI are scarce. We compare findings in repeat ablation procedures after a first PFA to findings in repeat ablation procedures after a first cryoballoon ablation (CBA) based PVI. Methods and result A total of 550 consecutively enrolled patients underwent PFA or CBA index PVI. Repeat ablations in patients with symptomatic atrial arrhythmia recurrences were analysed. A total of 22/191 (12%) patients after index PFA-PVI and 44/359 (12%) after CBA-PVI underwent repeat ablation. Reconduction of any pulmonary vein (PV) was detected by multipolar spiral mapping catheter at each PV with careful evaluation of PV potentials and by 3D-mapping in 16/22 patients (73%) after PFA-PVI and in 33/44 (75%) after CBA-PVI (P = 1.000). Of 82 initially isolated PVs after PFA-PVI, 31 (38%) were reconducting; of 169 isolated PVs after CBA-PVI, 63 (37%) were reconducting (P = 0.936). Clinical atrial tachycardia occurred similarly in patients after PFA (5/22; 23%) and CBA (7/44; 16%; P = 0.515). Roof lines were set more often after PFA- (8/22; 36%) compared with CBA-PVI (5/44; 11%; P = 0.023). Repeat procedure duration [PFA: 87 (76, 123) min; CBA: 93 (75, 128) min; P = 0.446] was similar and fluoroscopy time [PFA: 11 (9, 14) min; CBA: 11 (8, 14) min; P = 0.739] equal between groups at repeat ablation. Conclusion During repeat ablation after previous PFA- or CBA-based PVI, electrical PV-reconduction rates and patterns were similar. [ABSTRACT FROM AUTHOR]

Background: Recently, treatment of equine atrial tachycardia by three‐dimensional electro‐anatomical mapping (3D EAM) and radiofrequency catheter ablation (RFCA) has been described. Myocardial sleeves in the caudal vena cava and pulmonary veins are a potential trigger for initiation and perpetuation of atrial tachycardia and atrial fibrillation in the horse. Isolation of these myocardial sleeves by RFCA may be an effective treatment for these arrhythmias. Objectives: To describe the feasibility of 3D EAM and RFCA to isolate caudal vena cava and pulmonary veins in adult horses using 3D mapping and a contact force (CF)‐guided ablation system. Study design: In vivo experiments. Methods: 3D EAM and RFCA was performed in five horses without cardiovascular disease under general anaesthesia, using the CF‐guided system CARTO®3. Point‐by‐point RFCA aimed for isolation of caudal vena cava and pulmonary veins. Radiofrequency energy was delivered in power‐controlled mode with a target power of 45 W, CF between 10 and 15 g and 30 mL/min irrigation rate, until an ablation‐index of 450–500 was reached. Results: In the right atrium, myocardial sleeves of the caudal vena cava were isolated (n = 5). In the left atrium, isolation of ostium II (n = 3), ostium III (n = 1) and ostium I, II and III en bloc (n = 1) was performed. Successful isolation was confirmed by entrance and exit block. Main limitations: Horses were euthanised at the end of the procedure, so long term effects such as potential reconnection of isolated veins could not be studied. Conclusions: This is the first description of 3D EAM and RFCA with CARTO®3 in horses, thereby showing the technical feasibility and successful caudal vena cava and pulmonary vein isolation. CF measurement allowed monitoring of catheter‐tissue contact, resulting in efficient acute lesion creation as confirmed by entrance and exit block. This is a promising treatment for cardiac arrhythmias in horses. [ABSTRACT FROM AUTHOR]

Background: Treating atrial tachycardia (AT) originating from left atrial appendage (LAA) needs sometimes electrical isolation of LAA. We report a case of AT originating from LAA successfully treated with electrical isolation using the novel lattice-tip pulsed-field/radiofrequency ablation (PFA/RFA) catheter. Case summary: A 55-year-old female patient with a history of three focal ablative attempts for a highly symptomatic AT originating from the LAA in different centers was admitted to our department for the recurrence of the clinical tachycardia. Electrical isolation of the LAA (LAAEI) was successfully performed with a lattice-tip PFA/RFA ablation catheter. Six weeks after the procedure, an invasive re-mapping study indicated a durable electrical LAA isolation; therefore, a 24-mm-sized LAA occlusion device (WATCHMAN FLX device, Boston Scientific, Plymouth, MN, USA) was implanted. Discussion: In this case, we successfully treated an atrial tachycardia originating from LAA using the recently approved lattice-tip PFA/RFA ablation catheter. The combination between two energy sources during the same procedure could potentially improve lesions transmurality offering a new promising solution for the treatment of complex atrial tachycardias. Left atrial appendage electrical isolation using the novel lattice-tip PFA/RFA catheter. Purple signals were recorded using a spiral mapping catheter positioned in LAA. White signals were recorded from the 9-electrodes-Lattice-tip ablation catheter. Green signals are recorded from a deflectable multipolar catheter positioned in coronary sinus. [ABSTRACT FROM AUTHOR]

Speech induced atrial tachycardia is peculiar and an extremely uncommon clinical situation. Though the exact patho-mechanism for such an association cannot be ascertained. It is postulated to be caused by cardiac autonomic modulation by vagal innervation around the ganglionated plexus (GP) of the heart. We hereby present a unique case of atrial tachycardia which could be induced only by speech and was successfully mapped and ablated on to the floor of left atrium (LA), which is a possible site of posteromedial left atrial ganglionated plexus.

Abstract In the field of cardiac electrophysiology, there is a universal desire: the discovery of a flawless diagnostic maneuver for supraventricular tachycardias (SVTs). This is not merely a wish but a shared odyssey. To improve diagnostic accuracy and achieve sufficient sensitivity and specificity, numerous diagnostic maneuvers have been proposed. However, each has its limitations and prompts a search for new diagnostic techniques. This continuous cycle of discovery and refinement, which we titled “SVT Quest” is reviewed in chronological sequence. This adventure in diagnosing narrow QRS tachycardia unfolds in 3 steps: Step 1 involves differentiating atrial tachycardia from other SVTs based on the observations such as V‐A‐V or V‐A‐A‐V response, ΔAA interval, VA linking, the last entrainment sequence, and response to the atrial extrastimulus. Step 2 focuses on differentiating orthodromic reciprocating tachycardia from atrioventricular nodal reentrant tachycardia based on the observations such as tachycardia reset upon the premature ventricular contraction during His refractoriness, uncorrected/corrected postpacing interval, differential ventricular entrainment, orthodromic His capture, transition zone analysis, and total pacing prematurity. Step 3 characterizes the concealed nodoventricular/nodofascicular pathway and His‐ventricular pathway‐related tachycardia based on observations such as V‐V‐A response, ΔatrioHis interval, and paradoxical reset phenomenon. There is no single diagnostic maneuver that fits all scenarios. Therefore, the ability to apply multiple maneuvers in a case allows the operator to accumulate evidence to make a likely diagnosis. Let's embark on this adventure!

A 70-year-old man with hypertensive heart disease underwent catheter ablation of persistent atrial fibrillation. After completing the pulmonary vein isolation, atrial burst pacing induced an annular atrial tachycardia (AT). Overdrive pacing exhibited constant fusion, indicating a macroreentrant mechanism of the AT. However, the CARTO3 activation map created using the Octaray catheter (both Biosense Webster, Irvine, CA) exhibited a centrifugal spread with the earliest activation site at the 4 o'clock position of the tricuspid annulus. In contrast, the Ripple map revealed a clear reentrant circuit with its isthmus located at the 4–6 o'clock position of the tricuspid annulus. The local electrograms in these areas recorded systolic and diastolic potentials simultaneously, and the misannotation of the large far-field potentials caused this discrepant result. Handling low-amplitude complex fractionated electrograms remains a challenge in creating a precise activation mapping. The Ripple map, especially when combined with the Octaray catheter, was effective in dynamically visualizing all these electrograms and accurately delineating the reentrant circuit.

Abstract Background Atrial tachycardia poses challenges in patient management due to the associated risks of stroke and systemic embolism. While anticoagulation is recommended in atrial fibrillation (AF), its role in atrial tachycardia remains less defined. This prospective study aimed to evaluate the efficacy and safety of apixaban, a direct oral anticoagulant, in individuals diagnosed with left-sided atrial tachycardias. Methods Patients diagnosed with left-sided atrial tachycardia (n = 439) were observed over 3 years. Baseline characteristics, medication regimens, and clinical outcomes were assessed. Apixaban-treated individuals (n = 213) received standard or reduced dosages, while the control group (n = 226) received standard care. Primary outcomes included stroke, systemic embolism, bleeding, and mortality rates. Results Baseline characteristics were comparable between groups. The apixaban cohort showed a lower incidence of stroke (7.0% vs. 9.3%, p = 0.027) and decreased all-cause mortality (11.7% vs. 12.8%, p = 0.012) compared to controls. No significant differences were found in major bleeding or systemic embolization between groups. Conclusion Apixaban demonstrated a potential benefit in reducing stroke and mortality rates in patients with left-sided atrial tachycardia. While requiring further validation, these findings suggest a potential role for apixaban in anticoagulation strategies for atrial tachycardia management.

Introduction: There is a lack of studies in the literature directly investigating the relationship between atrial tachycardia (AT) and left atrial (LA)/left atrial appendage (LAA) thrombus, and current guidelines do not provide strong recommendations regarding the use of transesophageal echocardiography (TEE) before AT catheter ablation. This study aims to elucidate the relationship between AT and the presence of LA/LAA thrombus and contribute to the literature on the use of TEE before AT catheter ablation. Methods: This single‐center retrospective observational study screened patients who underwent TEE between February 10, 2019, and February 10, 2023. Patients were assigned to the AT patient and control groups. TEE was conducted to exclude thrombus in the AT ablation group. The control group included patients who underwent TEE for interatrial septum evaluation and had LA imaging during TEE but did not have atrial arrhythmia. To mitigate bias between the AT patient group and the control group, they were randomized 1:1 using propensity‐score matching (PSM). Following randomization, each group consisted of 49 patients. Results: All analyses were conducted after PSM. There were no statistically significant differences between the AT patient and control groups in terms of baseline clinical characteristics and echocardiographic features. Additionally, no significant differences were found between the blood viscosities calculated at low and high shear rates in both groups. The study revealed a significant difference between the two groups in the presence of LA spontaneous echo contrast (SEC) (24.5% in AT group vs 0% in Control group, p =.001), but not in the presence of thrombi (8.2% in AT group vs 0% in Control group, p =.117). Conclusion: Compared to the control group, the presence of SEC was significantly higher in the AT patient group. The increased frequency of SEC in AT patients suggests the hypothesis that AT may contribute to LA stasis. The routine use of TEE before AT catheter ablation remains controversial, despite the presence of LA thrombus and SEC in the AT patient group. The clinical assessment of thrombus presence before the procedure must be conducted on a patient‐specific basis. [ABSTRACT FROM AUTHOR]

In the field of cardiac electrophysiology, there is a universal desire: the discovery of a flawless diagnostic maneuver for supraventricular tachycardias (SVTs). This is not merely a wish but a shared odyssey. To improve diagnostic accuracy and achieve sufficient sensitivity and specificity, numerous diagnostic maneuvers have been proposed. However, each has its limitations and prompts a search for new diagnostic techniques. This continuous cycle of discovery and refinement, which we titled "SVT Quest" is reviewed in chronological sequence. This adventure in diagnosing narrow QRS tachycardia unfolds in 3 steps: Step 1 involves differentiating atrial tachycardia from other SVTs based on the observations such as V‐A‐V or V‐A‐A‐V response, ΔAA interval, VA linking, the last entrainment sequence, and response to the atrial extrastimulus. Step 2 focuses on differentiating orthodromic reciprocating tachycardia from atrioventricular nodal reentrant tachycardia based on the observations such as tachycardia reset upon the premature ventricular contraction during His refractoriness, uncorrected/corrected postpacing interval, differential ventricular entrainment, orthodromic His capture, transition zone analysis, and total pacing prematurity. Step 3 characterizes the concealed nodoventricular/nodofascicular pathway and His‐ventricular pathway‐related tachycardia based on observations such as V‐V‐A response, ΔatrioHis interval, and paradoxical reset phenomenon. There is no single diagnostic maneuver that fits all scenarios. Therefore, the ability to apply multiple maneuvers in a case allows the operator to accumulate evidence to make a likely diagnosis. Let's embark on this adventure! [ABSTRACT FROM AUTHOR]

Background: Patients may develop atrial tachycardia (AT) after left atrial (LA) ablation of persistent atrial fibrillation (AF). Methods: The population consisted of 101 consecutive patients (age = 64.3 ± 8.7 years, 70 males (69%), LA = 4.6 ± 0.8 cm, ejection fraction = 48.5 ± 16%) undergoing their initial procedure for persistent AF. After pulmonary vein isolation, patients either underwent posterior LA isolation (n = 50; study group) or linear ablation at the LA roof with verification of conduction block (n = 51; control group). Results: A repeat procedure was performed in 17 (34%) and 28 (55%) patients in the study and control groups, respectively (p = 0.02). Patients in the study group were less likely to develop AT (9/50 [18%] vs. 18/51 [35%]; p = 0.02), roof-dependent (1/50 [2%] vs. 8/51 [16%]; p = 0.008), and multi-loop AT (6/50 [12%] vs. 14/51 [27%]; p = 0.03) as compared to controls. Among various factors, only posterior LA isolation was associated with a lower likelihood of AT recurrence and roof tachycardia at redo procedure (OR, 0.37; 95% CI, 0.1 to 1.00, p = 0.05, and OR, 0.1, 95% CI, 0.01 to 0.96; p < 0.05, respectively). Conclusions: In patients with persistent AF, posterior LA isolation is associated with a lower risk of a redo procedure, roof-dependent macro-reentry, and post-ablation AT in general as compared to controls who only received roof ablation. Posterior LA isolation also obviates the need for pacing maneuvers, and may be a more definitive endpoint than linear ablation at the LA roof. [ABSTRACT FROM AUTHOR]

Background: The relationship between induction and recurrence due to atrial tachycardia (AT) and left atrial (LA) matrix progression after atrial fibrillation (AF) ablation remains unclear. Methods: One hundred fifty-two consecutive patients with paroxysmal and persistent AF who underwent pulmonary vein isolation (PVI) and cavo-tricuspid isthmus (CTI) ablation and achieved sinus rhythm before the procedure were classified into three groups according to the AT pattern induced after the procedure: group N (non-induced), F (focal pattern), and M (macroreentrant pattern) in 3D mapping. Results: The total rate of AT induction was 19.7% (30/152) in groups F (n = 13) and M (n = 17). Patients in group M were older than those in groups N and F, with higher CHADS2/CHA2DS2-VASc values, left atrial enlargement, and low-voltage area (LVA) size of LA. The receiver operating characteristic curve determined that the cut-off LVA for macroreentrant AT induction was 8.8 cm2 (area under the curve [AUC]: 0.86, 95% confidence interval [CI]: 0.75–0.97). The recurrence of AT at 36 months in group N was 4.1% (5/122), and at the second ablation, all patients had macroreentrant AT. Patients with AT recurrence in group N had a wide LVA at the first ablation, and the cut-off LVA for AT recurrence was 6.5 cm2 (AUC 0.94, 95%CI 0.88–0.99). Adjusted multivariate analysis showed that only LVA size was associated with the recurrence of macroreentrant AT (odds ratio 1.21, 95%CI 1.04–1.51). Conclusions: It is important to develop a therapeutic strategy based on the LVA size to suppress the recurrence of AT in these patients. [ABSTRACT FROM AUTHOR]

Background: Although previous studies have shown the isolated areas after pulmonary vein isolation (PVI) using cryoballoons (CB) (CB-PVI), no studies have investigated the association between the isolated area and recurrence of atrial fibrillation (AF) and atrial tachycardia (AT). This single-center observational study investigated the association between the ablated area and recurrence rate after durable CB-PVI for paroxysmal AF. Methods: This study included 76 patients with paroxysmal AF who underwent CB-PVI and established durable PVI with a second procedure, regardless of AF/AT recurrence, 6 months after the first procedure. To compare the ablated zones, we quantified the left- and right-sided PV antral isolation areas and non-ablated posterior wall (PW) area. We examined non-ablated areas of the PW and AF/AT recurrence in the chronic phase. Results: In total, 16 of the 76 patients had AF/AT recurrence. The mean follow-up duration was 34 months. The non-ablated PW area (14.0 ± 4.6 cm2 vs. 11.5 ± 3.7 cm2; p = 0.0213) and the ratio of the non-ablated PW area to the whole PW area (NAPW) (52.9 ± 9.1% vs. 44.8 ± 9.8%; p = 0.003) were significantly higher in the AF/AT recurrence group than in the AF/AT non-recurrence group. NAPW > 50% was an independent predictor of AF/AT recurrence. Conclusion: The NAPW after durable CB-PVI is associated with AF/AT recurrence. PW isolation or additional applications on the PV antrum with cryoballoon may be considered in addition to PVI in paroxysmal AF, especially in patients with dilated left atria. [ABSTRACT FROM AUTHOR]

Introduction: Ablation of scar‐related reentrant atrial tachycardia (SRRAT) involves identification and ablation of a critical isthmus. A graph convolutional network (GCN) is a machine learning structure that is well‐suited to analyze the irregularly‐structured data obtained in mapping procedures and may be used to identify potential isthmuses. Methods: Electroanatomic maps from 29 SRRATs were collected, and custom electrogram features assessing key tissue and wavefront properties were calculated for each point. Isthmuses were labeled off‐line. Training data was used to determine the optimal GCN parameters and train the final model. Putative isthmus points were predicted in the training and test populations and grouped into proposed isthmus areas based on density and distance thresholds. The primary outcome was the distance between the centroids of the true and closest proposed isthmus areas. Results: A total of 193 821 points were collected. Thirty isthmuses were detected in 29 tachycardias among 25 patients (median age 65.0, 5 women). The median (IQR) distance between true and the closest proposed isthmus area centroids was 8.2 (3.5, 14.4) mm in the training and 7.3 (2.8, 16.1) mm in the test group. The mean overlap in areas, measured by the Dice coefficient, was 11.5 ± 3.2% in the training group and 13.9 ± 4.6% in the test group. Conclusion: A GCN can be trained to identify isthmus areas in SRRATs and may help identify critical ablation targets. [ABSTRACT FROM AUTHOR]

Background: Atrial tachycardia poses challenges in patient management due to the associated risks of stroke and systemic embolism. While anticoagulation is recommended in atrial fibrillation (AF), its role in atrial tachycardia remains less defined. This prospective study aimed to evaluate the efficacy and safety of apixaban, a direct oral anticoagulant, in individuals diagnosed with left-sided atrial tachycardias. Methods: Patients diagnosed with left-sided atrial tachycardia (n = 439) were observed over 3 years. Baseline characteristics, medication regimens, and clinical outcomes were assessed. Apixaban-treated individuals (n = 213) received standard or reduced dosages, while the control group (n = 226) received standard care. Primary outcomes included stroke, systemic embolism, bleeding, and mortality rates. Results: Baseline characteristics were comparable between groups. The apixaban cohort showed a lower incidence of stroke (7.0% vs. 9.3%, p = 0.027) and decreased all-cause mortality (11.7% vs. 12.8%, p = 0.012) compared to controls. No significant differences were found in major bleeding or systemic embolization between groups. Conclusion: Apixaban demonstrated a potential benefit in reducing stroke and mortality rates in patients with left-sided atrial tachycardia. While requiring further validation, these findings suggest a potential role for apixaban in anticoagulation strategies for atrial tachycardia management. [ABSTRACT FROM AUTHOR]

Remote magnetic navigation (RMN) presents a promising approach for catheter ablation in complex arrhythmias. This study aims to offer additional insights into the feasibility, safety, and efficacy of RMN for catheter ablation of epicardial atrial and ventricular arrhythmias in patients without structural heart disease. We present a case series of three patients (39-year-old female, 28-year-old female, and 17-year-old male) referred to our institute for epicardial ablation following unsuccessful endocardial procedures. The first patient exhibited approximately 40,000 monomorphic premature ventricular complexes (PVCs) in a 24-hour Holter recording, while the second patient experienced incessant left ventricular tachycardia (VT). In both cases, the QRS morphology indicated an epicardial origin of the arrhythmia. The third patient suffered from incessant atrial tachycardia (AT) originating from the distal portion of the vein of Marshall (VOM). Epicardial 3D electroanatomic mapping and ablation with RMN were performed with ease and minimal fluoroscopy usage. Coronary angiogram visualization on the RMN screen provided real-time information on the catheter tip's position relative to the coronary arteries. In all cases, the earliest signals were recorded epicardially, and unipolar recordings displayed sharp negative deflections at the sites of successful ablation. In the first patient, pace mapping was superior in the epicardium compared to the endocardium, and PVCs were eradicated by epicardial ablation. In the second patient, epicardial ablation immediately terminated the VT. In the third patient, epicardial ablation at the site exhibiting a distinct VOM potential promptly terminated the AT. No perioperative complications were observed, and all patients remained asymptomatic and free of arrhythmias during long-term follow-up. Our findings suggest that RMN is a feasible, effective, and safe approach for epicardial ablation of left ventricular outflow tract PVCs and VT, as well as atrial tachycardia originating from the VOM. [ABSTRACT FROM AUTHOR]

We investigated whether posterior left atrial (LA) box isolation (BOXI) improved the rhythm outcome of catheter ablation in persistent atrial fibrillation (AF) when compared with complex fractionated atrial electrograms (CFAE) ablation. A total of 183 patients with persistent AF who underwent catheter ablation were recruited from the AF ablation registry database at Mie University Hospital; 68 patients underwent CFAE ablation, and 115 patients underwent BOXI. All patients underwent clinical review and 24-hour ambulatory ECG monitoring to detect asymptomatic arrhythmias at 1, 3, 6, and 12 months post-initial ablation. Patients in the BOXI group had a significantly higher freedom from AF rate than those in the CFAE group (81.5% vs 63.9%, p=0.014), with a similar trend in propensity score-matched patients (p=0.003). The BOXI procedure emerged as the only independent prognostic factor for freedom from AF recurrence. BOXI led to greater reduction in left atrial diameter from baseline to 3-6 months post-catheter ablation compared to CFAE ablation. Thus, BOXI may offer superiority over CFAE ablation in maintaining sinus rhythm in patients with persistent AF, in addition to pulmonary vein isolation. [ABSTRACT FROM AUTHOR]

Key Clinical Message: This case illustrates the safety and efficacy of pulse field ablation (PFA) in the short and medium term. It could be used to isolate extra pulmonary sites including the posterior wall. PFA could be used in the treatment of atrial tachycardias both focal and reentrant in combination with ultrahigh density electroanatomic mapping. It is also important to understand that different catheter shapes are available and their use can be tailored to the targeted anatomical site. [ABSTRACT FROM AUTHOR]

The left atrial appendage (LAA) is now recognized as a significant contributor to arrhythmia and thromboembolism in patients with a history of atrial fibrillation. Thoracoscopic exclusion of the LAA is made possible with the AtriClip device. In this report, we describe the case of a 65-year-old man with history of multiple left atrial ablation procedures and LAA clipping. He developed a microreentrant atrial tachycardia originating from the anterior base of the LAA stump, underwent complete isolation of the LAA, and had subsequent resolution of arrhythmogenic activity from the residual LAA stump. [ABSTRACT FROM AUTHOR]

A 34-year-old woman presented with palpitations and paroxysmal atrial fibrillation (AF). Workup revealed anterior mitral valve prolapse with severe mitral regurgitation. She was referred for surgical repair and underwent a mitral valve replacement, tricuspid valve repair, and bi-atrial cryoMAZE procedure with left atrial appendage ligation. Her postoperative course was complicated by inferior wall myocardial infarction. She subsequently presented with palpitations and underwent electrophysiology study and ablation. This case illustrates pitfalls associated with the surgical MAZE procedure and highlights the challenges in postoperative atrial arrhythmias diagnosis and management. [ABSTRACT FROM AUTHOR]

A 70-year-old man with recurrent atrial fibrillation (AF) underwent transcatheter radiofrequency ablation after an earlier unsuccessful attempt. Although typical AF triggers were ablated, the patient's condition persisted, leading to the identification of the interatrial septum (IAS) as the probable source of the tachycardia trigger. Given the depth and thickness of the IAS, traditional radiofrequency ablation proved ineffective. However, using the alternative method of bipolar radiofrequency catheter ablation (B-RFCA), the atrial tachycardia was successfully terminated. B-RFCA demonstrates potential for effectively terminating tachycardias originating from deep intramural locations, suggesting its potential as a pivotal technique for complex cases with septal atrial tachycardia. [ABSTRACT FROM AUTHOR]

Copyright of Herzschrittmachertherapie und Elektrophysiologie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aims Wild-type transthyretin amyloid cardiomyopathy (ATTRwt-CM) is often accompanied by atrial fibrillation (AF), atrial flutter (AFL), and atrial tachycardia (AT), which are difficult to control because beta-blockers and antiarrhythmic drugs can worsen heart failure (HF). This study aimed to investigate the outcomes of catheter ablation (CA) for AF/AFL/AT in patients with ATTRwt-CM and propose a treatment strategy for CA. Methods and results A cohort study was conducted on 233 patients diagnosed with ATTRwt-CM, including 54 who underwent CA for AF/AFL/AT. The background of each arrhythmia and the details of the CA and its outcomes were investigated. The recurrence-free rate of AF/AFL/AT overall in ATTRwt-CM patients with multiple CA was 70.1% at 1-year, 57.6% at 2-year, and 44.0% at 5-year follow-up, but CA significantly reduced all-cause mortality [hazard ratio (HR): 0.342, 95% confidence interval (CI): 0.133–0.876, P = 0.025], cardiovascular mortality (HR: 0.378, 95% CI: 0.146–0.981, P = 0.045), and HF hospitalization (HR: 0.488, 95% CI: 0.269–0.889, P = 0.019) compared with those without CA. There was no recurrence of the cavotricuspid isthmus (CTI)–dependent AFL, non-CTI–dependent simple AFL terminated by one linear ablation, and focal AT originating from the atrioventricular (AV) annulus or crista terminalis eventually. Twelve of 13 patients with paroxysmal AF and 27 of 29 patients with persistent AF did not have recurrence as AF. However, all three patients with non-CTI–dependent complex AFL not terminated by a single linear ablation and 10 of 13 cases with focal AT or multiple focal ATs originating beyond the AV annulus or crista terminalis recurred even after multiple CA. Conclusion The outcomes of CA for ATTRwt-CM were acceptable, except for multiple focal AT and complex AFL. Catheter ablation may be aggressively considered as a treatment strategy with the expectation of improving mortality and hospitalization for HF. [ABSTRACT FROM AUTHOR]

Background Double-wave macrore-entry is a rare mechanism of atrial tachycardia with limited documentation in the literature. We present a three-dimensional documentation of a double-wave 'typical' atrial flutter in a patient with extensive atrial cardiomyopathy. Case summary A 78-year-old female with a history of atrial cardiomyopathy and dual-chamber pacemaker for sinus node disease presented with palpitations and incessant atrial flutter. Electrophysiological study revealed a regular tachycardia with a cycle length (TCL) of 230 ms, with proximal to distal coronary sinus (CS) activation. Three-dimensional mapping identified two independent wavefronts circulating the cavotricuspid isthmus (CTI), each with a TCL of 460 ms. Cavotricuspid isthmus ablation resulted in conversion into a distinct tachycardia with left atrial roof origin. Linear ablation in this location slowed the TCL to 435 ms with concentric CS activation and another CTI dependent atrial flutter was mapped, this time with only one wavefront of activation. Further ablation with a second, more lateral, line in the CTI led to tachycardia interruption. Given the extensive atrial scarring and high arrhythmic recurrence risk, atrioventricular node ablation was performed. Discussion Double-wave re-entrant tachycardias were primarily observed in experimental models, precipitating acceleration of ventricular and supraventricular tachycardias via extrastimulation. In our case, there is documentation of a spontaneous double-wave of activation around the CTI, representing the first documented double-wave 'typical' atrial flutter. Unlike other cases in the literature, the two wavefronts were equidistant, which resulted in a regular tachycardia with TCL that was half of the single-wave cycle length. Three-dimensional propagation mapping was essential to visualize the two distinct wavefronts. [ABSTRACT FROM AUTHOR]

IntroductionAtrial tachycardia (AT) frequently occurs after cardiac surgery or surgical ablation procedures. The novel charge density-based mapping system (CDM) provides global chamber mapping and can detect crucial pathways of conduction; therefore, it has potential added value in catheter ablation (CA) of post-surgical ATs. We aimed to test the hypothesis that CDM-guided CA procedures are safe, feasible, and may improve outcome compared to conventional sequential 3D mapping (CARTO)-based CA.Methods and resultsConsecutive patients undergoing CA for post-surgical AT guided by CDM or CARTO were enrolled. Procedural safety and efficiency were analyzed. Acute success, one-year outcome was assessed. A total of 35 patients (mean age 60.8 ± 10.6 years, 42.9% female) underwent CA of AT using CDM (n = 20) and CARTO (n = 15). A total of 61 ATs were mapped (35 in CDM and 26 in CARTO group). Four patients had focal ATs, 22 macro re-entrant, and 8 patients had ATs with both mechanisms. No differences were found in procedural complication (CDM 3 vs. CARTO 1 patient, p = 0.61). There were no differences in procedure duration (185.9 vs. 147.9 min, p = 0.09), fluoroscopy dose (165.0 vs. 155.0 mGy, p = 0.31), RF application number (28.0 vs. 18.0, p = 0.17) or duration (1,251.5 vs. 1,060.0 s, p = 0.54). Acute success was 95.0% in CDM and 73.3% in CARTO group (p = 0.14). Cumulative AT recurrence rates were lower in CDM group compared to CARTO group (10.0% vs. 46.7%, p = 0.02).ConclusionsThe CDM system is feasible. Our data suggest that patients treated with CDM-guided CA developed fewer AT recurrences as compared to CARTO-guided procedures.

Electroanatomic mapping guides complex atrial tachycardia ablations; however, challenges may emerge after pulmonary vein isolation. 3D mapping systems can reveal the mechanism of tachycardia and critical areas that need to be ablated. Sometimes, however, these areas may be located deep inside, to the extent that they cannot be successfully reached by endocardial ablation. In this study, we present a unique case of a patient in whom vein of Marshall (VOM) ethanol ablation, a conventional secondary intervention, promptly terminated a Marshall bundle–related atrial tachycardia without further endocardial radiofrequency application, suggesting VOM ethanol ablation as a potential primary strategy.

Objectives: The relationship between left atrial (LA) size and atrial fibrillation (AF) is well-established. However, the specifics of LA regional remodeling and its connection to left atrial tachycardia (LA-AT) post-ablation in patients with non-paroxysmal AF are less understood. This study aims to explore how LA dimensions are related to the development of LA-AT following AF ablation procedures in these patients. Methods: This study focused on 73 patients with non-paroxysmal atrial fibrillation (average age 52, predominantly male, with a nearly even split between persistent and long-lasting persistent AF), all undergoing their first catheter ablation for AF. Prior to the ablation, left atrial dimensions were determined through computed tomography, measuring the maximal transverse, anteroposterior, and superoinferior diameters. Results: Over an average follow-up period of 23 months, 31.5% of the patients (Group 1) experienced left atrial tachycardia (LA-AT) that required a second linear ablation procedure. This group had significantly larger left atrial (LA) dimensions in terms of transverse, anteroposterior, and superoinferior measurements compared to the other group (Group 2). However, the recurrence of atrial fibrillation (AF) was not linked to any specific LA diameter. The anteroposterior diameter was identified as a significant predictor (p=0.002, HR 2.3, 95% CI 1.3-3.8) for LA-AT occurrence through multivariate analysis. Conclusions: Eccentric dilatation involving the anteroposterior diameter is a significant predictor for the occurrence of LA-AT in patients with non-paroxysmal AF after catheter ablation. Keywords Atrial fibrillation; Atrial flutter; Atrial tachycardia; Left atrial diameter; Catheter ablation; Computed tomography

Abstract Background Atrial tachycardia (AT) originating from the left atrial appendage (LAA) is uncommon and the most difficult arrhythmia to eliminate. Therefore, we present the case of a 5-year-old girl with tachycardia-induced cardiomyopathy (TIC) caused by AT originating from the LAA and successfully treated with RFCA associated to left atrial appendectomy. With resolution of AT, we observed a progressive improvement of LV function. The effectiveness and safety of this combination therapy were evaluated over a one-month follow-up period. Case presentation A 5 -year-old female was evaluated for three days of incessant cough and a syncopal episode. Surface echocardiography and 24-hour monitoring showed that the infant had persistent atrial tachycardia. Echocardiography revealed an enlarged tele diastolic diameter (46.1 mm) and malfunctioning (EF 28.53%) left ventricle. The location of the lesion at the apex of the LAA was further confirmed by electrophysiological study and RFCA. After RFCA, the infant’s ECG monitor showed that sinus rhythm was maintained for up to 22 h. Subsequently, atrial tachycardia recurred and sinus rhythm disappeared. Finally, atrial appendectomy was performed and sinus rhythm returned to normal. Conclusions The heart function of the infant improved and sinus rhythm was maintained, further demonstrating the safety and effectiveness of combined treatment with RFCA and atrial appendectomy after electrophysiological localization of AT from LAA to TIC.

Background: Atypical atrial flutter (AFL) can be challenging to ablate, especially when involving dual-loop re-entry. We sought to assess the electroanatomical characteristics of single- and dual-loop AFLs in patients undergoing catheter ablation. Methods: We analyzed 25 non-cavotricuspid isthmus-dependent macro-re-entrant AFL in 19 consecutive patients. Three-dimensional high-density activation mapping was performed, and active re-entry loops were confirmed by entrainment mapping. Results: Of 25 AFLs (24 left, 1 right atrial), 13 (52%) exhibited dual-loop re-entry. The most common circuits included, in 6/13 (46% of dual loops), a perimitral re-entry with a second loop around the right/left pulmonary veins (PV) and, in 6/13 (46%), involved a right PV ostium with a second loop around either a functional conduction block or another PV. Ablation at the common isthmus of dual-loop AFLs and at the critical isthmus of single-loop AFLs terminated the arrhythmia more frequently than ablation at a secondary isthmus of dual-loop AFLs (5/6 (83%) and 8/11 (73%) versus 1/8 (13%), respectively, p = 0.013). Conclusions: More than half of AFLs exhibited a dual-loop re-entrant mechanism. Most critical isthmuses were found at the mitral isthmus, the left atrial roof or right PV ostia. Ablation targeting the common isthmus resulted in a higher termination rate. [ABSTRACT FROM AUTHOR]

Background Complex atrial tachycardia (AT) is commonly observed in patients with cardiac surgery. High-density mapping is widely adopted for catheter ablation of complex AT in patients with cardiac surgery. Several case reports have described that PentaRay mapping catheter can be trapped in the mechanical valve and sheared off and successful retrieval of the spline by a snare system. We described a rare case in which PentaRay mapping catheter spline was successfully retrieved from the distal anterior tibial artery by direct syringe suction via the diagnostic catheter following entrapment in the mechanical mitral valve (MV) and rupture of the spline. Case summary A 70-year-old female with mechanical bileaflet MV underwent catheter ablation for AT. During mapping in left atrium, the catheter was entrapped in mechanical MV and sheared off. We attempted to release the entrapped the spline by advancing the ablation catheter towards the stuck disc and pushing on the hinge portion of the disc with the catheter tip. The stuck and closed disc was opened, and the deeply entrapped spline was released. However, the entrapped PentaRay spline floated through the Valsalva sinus and strayed into the distal left anterior tibial artery. Fortunately, we successfully retrieved the spline from the distal anterior tibial artery by direct syringe suction instead of a snare system. Discussion The possibility of the entrapment and subsequent rupture of the spline should always be considered during mapping the site close to mechanical valve. A rapid retrieval of embolized material should be carried out. If the spline strays into the distal and small artery in which the snare system is difficult to advance, a direct syringe suction via the diagnostic catheter may be attempted. [ABSTRACT FROM AUTHOR]

Background: Atrial tachycardia (AT) originating from the left atrial appendage (LAA) is uncommon and the most difficult arrhythmia to eliminate. Therefore, we present the case of a 5-year-old girl with tachycardia-induced cardiomyopathy (TIC) caused by AT originating from the LAA and successfully treated with RFCA associated to left atrial appendectomy. With resolution of AT, we observed a progressive improvement of LV function. The effectiveness and safety of this combination therapy were evaluated over a one-month follow-up period. Case presentation: A 5 -year-old female was evaluated for three days of incessant cough and a syncopal episode. Surface echocardiography and 24-hour monitoring showed that the infant had persistent atrial tachycardia. Echocardiography revealed an enlarged tele diastolic diameter (46.1 mm) and malfunctioning (EF 28.53%) left ventricle. The location of the lesion at the apex of the LAA was further confirmed by electrophysiological study and RFCA. After RFCA, the infant's ECG monitor showed that sinus rhythm was maintained for up to 22 h. Subsequently, atrial tachycardia recurred and sinus rhythm disappeared. Finally, atrial appendectomy was performed and sinus rhythm returned to normal. Conclusions: The heart function of the infant improved and sinus rhythm was maintained, further demonstrating the safety and effectiveness of combined treatment with RFCA and atrial appendectomy after electrophysiological localization of AT from LAA to TIC. [ABSTRACT FROM AUTHOR]

In activation mapping of reentrant atrial tachycardia (AT), there was no reference for window of interest (WOI). We examined the timing of a successful termination site from end of the P wave and attempted to determine whether the critical isthmus can be identified using activation mapping when WOI was set as end to end of the P wave. Forty patients with 54 reentrant AT who underwent 3D electroanatomic mapping and radiofrequency catheter ablation were evaluated retrospectively. The critical isthmus was defined as a successful termination site. We evaluate critical isthmus timing from end of the P wave and percentage of critical isthmus timing from end of the P wave to tachycardia cycle length. In 54 reentrant AT, Macro-reentry was identified in 46 (85.2%) and micro-reentry was identified in eight (14.8%). The timing of the critical isthmus site from end of the P wave was − 4.0 ± 31.1 ms (Macro-reentry vs. Micro-reentry; − 8.9 ± 29.4 ms vs. 24.0 ± 26.7 ms; P = 0.005). The percentage of critical isthmus timing from end of the P wave/tachycardia cycle length was − 1.4 ± 10.5% (Macro-reentry vs. Micro-reentry; − 3.1 ± 9.8% vs. 8.3 ± 9.3%, P = 0.004) The critical isthmus of reentrant AT is located within 10% backward and forward from end of the P wave to tachycardia cycle length. Setting the WOI from end to end of the P wave is useful for identification of the critical isthmus through activation mapping. [ABSTRACT FROM AUTHOR]

In the past, it has been generally accepted that tachyarrhythmias other than atrial fibrillation (AF) such as atrial premature beats (APB) and atrial tachycardia (AT) are not of great clinical significance. However, with the development of detection methods in recent years, more and more clinical studies have found that the atrial ectopic activities of APB and AT except for AF are associated with the risk of stroke, and may further contribute to increased mortality. Meanwhile, a positive association has also been revealed between the frequency of this kind of atrial yarrhythmias, and incidence of adverse events such as AF and ischemic stroke, which may be mediated by subclinical atrial cardiomyopathy. There is still no clear definition of the clinical threshold for this type of arrhythmia and its excessive supraventricular ectopic activities at present. Therefore, it is essential to make regular detection and management of tachyarrhythmia other than AF by means such as ambulatory electrocardiography and by following standardized process. This article describes the relationship between such atrial arrhythmias and cardiogenic stroke, and introduces the role of detecting such arrhythmias in the assessment of cardiogenic stroke. [ABSTRACT FROM AUTHOR]

Key Clinical Message: A 46‐year‐old woman with congenitally corrected transposition of the great arteries (ccTGA) associated with dextrocardia, situs viscerus inversus, and left superior vena cava persistence presented with an incessant supraventricular tachycardia. Electrophysiological study was not conclusive in differential diagnosis of atrial tachycardia versus atypical atrioventricular (AV) nodal reentrant tachycardia, also due to the unconventional anatomy of the coronary sinus. By a comprehensive mapping of cardiac chambers, a double side slow‐pathway was localized in both atrial chambers and subsequently ablated by radiofrequency delivery without tachycardia changes. Aortic root and cusps were devoid of electrical activity. The muscular part of the sub‐pulmonary ventricle at the level of interatrial septum showed an earliest activation signal of −90 ms and ablation of this site was effective in abolish the tachycardia. This is the first case to report technical concerns of septal atrial tachycardia ablation in ccTGA associated with multiple anatomical malformations. Moreover, some peculiarities have been reported for the first time including the presence of double‐side AV nodal slow‐pathway and atypical localization of the tachycardia origin into the muscular part of the sub‐pulmonary ventricle instead of posterior pulmonary cusp. [ABSTRACT FROM AUTHOR]

Aims Catheter ablation (CA) of post-ablation left atrial tachycardias (LATs) can be challenging. So far, pulsed field ablation (PFA) has not been compared to standard point-by-point radiofrequency current (RFC) energy for LAT ablation. To compare efficacy of PFA vs. RFC in patients undergoing CA for LAT. Methods and results Consecutive patients undergoing LAT-CA were prospectively enrolled (09/2021–02/2023). After electro-anatomical high-density mapping, ablation with either a pentaspline PFA catheter or RFC was performed. Patients were matched 1:1. Ablation was performed at the assumed critical isthmus site with additional ablation, if necessary. Right atrial tachycardia (RAT) was ablated with RFC. Acute and chronic success were assessed. Fifty-six patients (n = 28 each group, age 70 ± 9 years, 75% male) were enrolled. A total of 77 AT (n = 67 LAT, n = 10 RAT; 77% macroreentries) occurred with n = 32 LAT in the PFA group and n = 35 LAT in the RFC group. Of all LAT, 94% (PFA group) vs. 91% (RFC group) successfully terminated to sinus rhythm or another AT during ablation (P = 1.0). Procedure times were shorter (PFA: 121 ± 41 vs. RFC: 190 ± 44 min, P < 0.0001) and fluoroscopy times longer in the PFA group (PFA: 15 ± 9 vs. RFC: 11 ± 6 min, P = 0.04). There were no major complications. After one-year follow-up, estimated arrhythmia free survival was 63% (PFA group) and 87% (RFC group), [hazard ratio 2.91 (95% CI: 1.11–7.65), P = 0.0473]. Conclusion Pulsed field ablation of post-ablation LAT using a pentaspline catheter is feasible, safe, and faster but less effective compared to standard RFC ablation after one year of follow-up. Future catheter designs and optimization of the electrical field may further improve practicability and efficacy of PFA for LAT. [ABSTRACT FROM AUTHOR]

Introduction: Atrial fibrillation and atrial flutter originating from the donor s heart is a commonly reported complication post heart transplant. Atrial tachyarrhythmia originating from the recipient s heart, propagated through recipient‐to‐donor connections, is rare with only few cases reported in the literature; most reported cases from our review occur years post‐transplant. Case: A 47‐year‐old male presented with atrial tachycardia 6 months post heart transplant. Electrophysiologic study demonstrated atrial fibrillation originating from native heart and propagated through atrio‐atrial connections to the donor heart. This arrhythmia was successfully terminated with radiofrequency ablation. Conclusion: Atrio‐atrial connection between recipient and donor can form as early as a few months post heart transplant. Radiofrequency ablation appears to be an effective treatment for atrial fibrillation propagated through donor‐to‐recipient connections. [ABSTRACT FROM AUTHOR]

Background: Omnipolar mapping (OT) is a novel tool to acquire omnipolar signals for electro-anatomical mapping, displaying true voltage and real-time wavefront direction and speed independent of catheter orientation. The aim was to analyze previously performed left atrial (LA) and left ventricular (LV) maps for differences using automated OT vs. standard bipolar settings (SD) and HD wave (HDW) algorithm. Methods: Previously obtained SD and HDW maps of the LA and LV using a 16-electrode, grid-shaped catheter were retrospectively analyzed by applying automated OT, comparing voltage, point density, pulmonary vein (PV) gaps, and LV scar area. Results: In this analysis, 135 maps of 45 consecutive patients (30 treated for LA, 15 for LV arrhythmia) were included. Atrial maps revealed significantly higher point densities using OT (21471) vs. SD (6682) or HDW (12189, p < 0.001). Mean voltage was significantly higher using OT (0.75 mV) vs. SD (0.61 mV) or HDW (0.64 mV, p < 0.001). OT maps detected significantly more PV gaps per patient vs. SD (4 vs. 2), p = 0.001. In LV maps, OT revealed significantly higher point densities (25951) vs. SD (8582) and HDW (17071), p < 0.001. Mean voltage was significantly higher for OT (1.49 mV) vs. SD (1.19 mV) and HDW (1.2 mV), p < 0.001. Detected scar area was significantly smaller using OT (25.3%) vs. SD (33.9%, p < 0.001). Conclusion: OT mapping leads to significantly different substrate display, map density, voltage, detection of PV gaps, and scar size, compared to SD and HDW in LA and LV procedures. Successful CA might be facilitated due to true HD maps. [ABSTRACT FROM AUTHOR]

Neonatal lupus may be associated with severe cardiac conduction problems, including high-degree or complete atrioventricular (AV) block, necessitating immediate pacemaker implantation during the neonatal period. However, cardiac manifestations of neonatal lupus may extend beyond AV block. Our case was a full-term female neonate, who presented with fetal arrhythmia and bradycardia with a heart rate of approximately 70–75 beats per minute after birth. Neonatal lupus was diagnosed later due to positive maternal and neonatal anti-SSA/Ro antibody. High-degree AV block was considered initially but bigeminy premature atrial contractions (PACs) with block was confirmed through a detailed evaluation of an electrocardiogram, which demonstrated unfixed PP intervals and fixed RR intervals. Atrial tachycardia (AT) developed when the neonate was 23 days old. The key point that differentiates high-degree AV block from PACs with block is the PP interval. The PP interval is fixed in high-degree AV block and unfixed in PACs with block. Careful differential diagnosis is required in neonates with bradycardia because it may lead to very different management. Our case presents a good illustration of why these arrhythmias need to be differentiated. Furthermore, our case may be the first of neonatal lupus with AT.

Key Clinical Message This case illustrates the safety and efficacy of pulse field ablation (PFA) in the short and medium term. It could be used to isolate extra pulmonary sites including the posterior wall. PFA could be used in the treatment of atrial tachycardias both focal and reentrant in combination with ultrahigh density electroanatomic mapping. It is also important to understand that different catheter shapes are available and their use can be tailored to the targeted anatomical site.

BackgroundThe mechanisms for atrial fibrillation (AF) recurrence after pulmonary vein isolation (PVI) catheter ablation are unclear. Non-PV organized atrial arrhythmias (PAC, AT, macro-reentrant AFL) are possible contributors; however the prevalence and effect of their ablation on recurrent AF are unknown. We hypothesize that the identification and ablation of non-PV organized atrial arrhythmias were associated with less AF recurrence.MethodsPatients who underwent repeat ablation for recurrent AF after prior PVI were retrospectively enrolled. The prevalence and characteristics of PV reconnections and non-PV organized atrial arrhythmias were identified. The outcomes of time to clinical AF recurrence, heart failure (HF) hospitalization, and mortality were analyzed in patients using multivariable adjusted Cox regression.ResultsIn 74 patients with recurrent AF (age 66 ± 9 years, left atrial volume index 38 ± 10 ml/m2, 59% persistent AF), PV reconnections were found in 46 patients (61%), macro-reentrant atrial flutter in 27 patients (36%), and focal tachycardia in 12 patients (16%). Mapping and ablation of non-PV organized atrial arrhythmias were associated with a reduced recurrence of late clinical AF (adjusted HR 0.26, CI 0.08-0.85, p = 0.03) and the composite outcome of recurrence of late AF, HF hospitalization, and mortality (adjusted HR 0.38, CI 0.17-0.85, p = 0.02), with median follow-up of 1.6 (IQR 0.7-6.3) years. The presence of PV reconnections or empiric linear ablation was not associated with reduction in clinical AF or composite endpoints.ConclusionThe ablation of non-PV organized atrial arrhythmias resulted in a reduction of late clinical AF recurrence and composite outcome. In this challenging population, alternate mechanisms beyond PV reconnections need to be considered. Prospective studies are needed.

Abstract Background For patients with heart failure combined with complete left bundle branch block, cardiac resynchronization therapy is an important therapeutic method. If these patients also have atrial tachycardia, how to choose a treatment strategy deserves discussion. Case presentation A Chinese woman in her early 70s was admitted due to recurrent episodes of chest distress and asthma for 1 year. Physical and laboratory examinations showed filling of the jugular vein, lung rales, left enlargement of the heart boundary, edema of the lower limbs and elevation of N-terminal pro b-type natriuretic peptide. An electrocardiogram showed atrial tachycardia and a left bundle branch block. An echocardiography revealed enlargement of the left ventricle and left ventricular systolic dysfunction. After obtaining informed consent, the treatment strategy decided upon by the team was to use biventricular cardiac resynchronization therapy treatment and to not intervene for the atrial tachycardia, with left bundle branch area pacing as a backup. Due to twisted and narrow coronary vein branches, traditional biventricular pacing failed, and then, left bundle branch area pacing was attempted successfully. A follow-up echocardiography at 1 year showed improved systolic function. The outcomes for this patient are favorable, but the choice of interventional strategy is worthy of discussion in this case. Conclusion For patients with heart failure combined with left bundle branch block and atrial tachycardia, left bundle branch area pacing can replace traditional biventricular pacing for cardiac resynchronization therapy treatment, and the therapeutic effect is significant. However, multiple factors need to be considered when formulating strategies, including whether there is bundle branch block under sinus rhythm, the success and recurrence rate of atrial tachycardia ablation, the response of cardiac resynchronization therapy, the costs of different strategies, and instrument implantation issues.

Atrial tachyarrhythmias occurring after transcatheter atrial septal defect closure are not uncommon; however, those related to device stimulation are rare. Herein, a case involving a 24-year-old female, who developed drug-refractory atrial tachycardia during the early postoperative period, is reported. The results of electroanatomical mapping could eventually be obtained from both atria. They revealed a focal pattern, and the earliest site was located on the left atrial side of the superior atrial septum, between the left and right atrial discs of the device. An ablation catheter was inserted through the side of the device into the left atrial septum, and cauterization successfully achieved recovery of the sinus rhythm without device dislodgement. Atrial tachyarrhythmia related to mechanical stimulation with an atrial septal defect closure device in the early perioperative period is a rare complication. Catheter ablation with transseptal approach through the side of the device might be an option, although careful attention should be paid to the risk for device dislodgement. [ABSTRACT FROM AUTHOR]

A 60‐year‐old male patient suffered from frequent episodes of atrial tachycardia (AT), after the index procedure of catheter ablation for paroxysmal atrial fibrillation. During the repeat procedure, the activation map showed that the earliest activation site was located at the roof of left atrium. Multiple ablations at the earliest activation site on the roof failed to terminate the AT; however, ablation within the pulmonary artery at an adjacent anatomical site successfully eliminated the AT, even without recording distinct near‐field potential. [ABSTRACT FROM AUTHOR]