Atrial Arrhythmias In Patients Research Articles

Abstract 4137249: Left atrial functional reserve predicts recurrence of atrial arrhythmia following catheter ablation in patients with persistent atrial fibrillation

Background: Left atrial (LA) functional remodeling plays an essential role in the pathophysiological mechanisms of atrial fibrillation (AF). LA reservoir strain (LARS) measured by speckle-tracking echocardiography (STE) exhibits acceptable predictive value for recurrent atrial arrhythmia in patients with paroxysmal AF, while its performance in persistent AF remains inconclusive. Recently, LA functional reserve, a novel concept of LA mechanics in response to acute-volume overload, is drawing attention. Research Questions: Are LARS and LA functional reserve associated with recurrent atrial arrhythmia after catheter ablation in patients with persistent AF? Methods: Ninety-two patients who underwent first catheter ablation for persistent AF were included in the study. LARS at rest and LA functional reserve were assessed by STE 1-4 days before catheter ablation. LA functional reserve was calculated as change in LARS after passive leg lifting. Recurrence of arrhythmia was defined as atrial arrhythmia of ≥ 30 seconds duration after a 2-month blanking period. Results: The median values of LARS and LA functional reserve were 14.4 % (interquartile range [IQR] 10.9 to 18.2) and 1.0% (IQR -1.2 to 3.6), respectively. During a mean follow-up of 13.2 ± 9.9 months, 29 (31.5%) patients experienced recurrent AF. When we stratified patients into 2 groups according to LARS and LA functional reserve (below vs. above median values), patients with impaired LA functional reserve (< 1.0%) were at higher risk of AF recurrence (log-rank test p value=0.026), but this was not observed for LARS (Figure). In multivariable Cox proportional hazard analysis, impaired LA functional reserve was associated with recurrent atrial arrhythmia independent of AF risk factors, left ventricular ejection fraction and LARS at rest (adjusted hazard ratio 3.99, p=0.004). Conclusions: Evaluation of LA functional reserve may provide valuable information for optimal patient selection as well as follow-up strategy after catheter ablation in patients with persistent AF.

Efficacy and safety of ultrasound guided stellate ganglion block: developing new clinical indications beyond electrical storm

Abstract Background Percutaneous stellate ganglion block (PSGB) is recommended by the latest European guidelines for patients with drug and ventricular tachycardia (VT) ablation refractory electrical storm (ES). Yet, due to the strong antiarrhythmic potential, combined with the good safety profile, we’ve recently used it for to the prophylaxis of ventricular arrhythmias (VAs) in high-risk patients and the prophylaxis/treatment of atrial arrhythmias in patients with acute heart failure (HF). Purpose To describe our single-center experience with PSGB usage outside the conventional indication of ES. Methods We hereby describe our single center experience with PSGB from 2/2021 to 2/2024. Results 56 patients (87% male, mean age 64 ± 12 years) received a total of 91 PSGB performed with the lateral, ultrasound (US) guided technique. Most of the procedures consisted of a single bolus anesthetic injection of lidocaine plus ropivacaine, 27% in an additional continuous infusion, mainly with ropivacaine. All procedures except for 3 in a single patient who had previously received left cardiac sympathetic denervation, were performed on the left side. Most of the patients (61%) suffered ischemic cardiomyopathy (CMP), including 11 with an acute coronary syndrome; the rest had non-ischemic CMP. 63 PSGB (69%) were performed in patients with impending or manifested cardiogenic shock (SCAI classification B or more). Mean LVEF was 24 ± 12%. Most of the procedures (n=80, 88%) were performed due to ongoing refractory VAs, yet 6 (6%) aimed to prevent major VAs in high-risk patients, mostly in the setting of recent ES (within 1 month) and need for Levosimendan to support cardiac output, in one case due to recent stereotactic VT ablation, to prevent early VAs in the phase of acute radiation induced microvascular damage. All 6 were effective in preventing clinically significant VAs. Additionally, 5 single bolus PSGBs (5%) were performed due to atrial arrhythmias with high ventricular rate despite intravenous drugs in the setting of acute HF. Specifically, 3 patients had atrial fibrillation (AF), 1 patient runs of ectopic atrial tachycardia (AT) and 1 patient 2:1 atrial flutter. Left-sided PSGB significantly reduced (≥25% reduction) ventricular rate during AF and AT but not during the single case of 2:1 atrial flutter, in 2/3 AF cases a cardioversion into sinus rhythm occurred within 40 minutes from PSGB. Only 1 (1%) major complication occurred (respiratory arrest), that was quickly and effectively treated with lipid emulsion, while minor complications were observed in 11% of PSGBs (mostly transient left arm weakness). Conclusions Our data suggest that US-guided PSGB usage, thanks to its feasibility at bed-side and good safety profile, may expand, beyond ES, to not only VAs prevention in high-risk settings, but also to prophylaxis/treatment of atrial arrhythmias in critically ill patients with acute heart failure requiring concomitant inotropic support.

Divergent electrophysiologic action of dapagliflozin and empagliflozin on ventricular and atrial tachyarrhythmias in isolated rabbit hearts.

The use of SGLT-2 inhibitors has revolutionized heart failure therapy. Evidence suggests a reduced incidence of ventricular and atrial arrhythmias in patients with dapagliflozin or empagliflozin treatment. It is unclear to what extent the reduced arrhythmia burden is due to direct effects of the SGLT2 inhibitors or is solely a marker of improved cardiac function. One hundred five rabbit hearts were allocated to eight groups and retrogradely perfused, employing a Langendorff setup. Action potential duration at 90% of repolarization (APD90), QT intervals, effective refractory periods, conduction velocity, and dispersion of repolarization were obtained with monophasic action potential catheters. A model for tachyarrhythmias was established with the IKr blocker erythromycin for QT prolongation associated proarrhythmia as well as the potassium channel opener pinacidil for a short-QT model. An atrial fibrillation (AF) model was created with isoproterenol and acetylcholine. With increasing concentrations of both SGLT2 inhibitors, reductions in QT intervals and APD90 were observed, accompanied by a slight increase in ventricular arrhythmia episodes. During drug-induced proarrhythmia, empagliflozin succeeded in decreasing QT intervals, APD90, and VT burden whereas dapagliflozin demonstrated no significant effects. In the presence of pinacidil induced arrhythmogenicity, neither SGLT2 inhibitor had a significant impact on cardiac electrophysiology. In the AF setting, perfusion with dapagliflozin showed significant suppression of AF in the course of restitution of electrophysiological parameters whereas empagliflozin showed no significant effect on atrial fibrillation incidence. In this model, empagliflozin and dapagliflozin demonstrated opposite antiarrhythmic properties. Empagliflozin reduced ventricular tachyarrhythmias whereas dapagliflozin showed effective suppression of atrial arrhythmias.

Analysis of the endocardial stage of treatment of tachyarhythmias after open interventions for atrial fibrillation. Experience of one center

AIM: To study EFI parameters and features of recurrent atrial tachyarrhythmias in patients who underwent surgical correction of AF.
 MATERIALS AND METHODS: from January 2013 to December 2021, 447 combined interventions were performed to eliminate AF using the labyrinth-3 and left atrial labyrinth techniques with correction of CHD (congenital heart disease) and/or coronary artery disease.
 Rhythm disturbances were detected in 57 (12.7%) patients at various follow-up periods. Endovascular interventions were performed in 39 patients. The average follow-up period after the endocardial stage was 34.37 (standard deviation 24.32) months. The median age of patients was 64 (58–67) years, 21 (54%) were men. The patients were divided into 2 groups: group 1 — after the classic biatrial (BA) labyrinth-3 — 23 (59%) patients, group 2 — after the left-atrial variant (LA) labyrinth-3 — 16 (41%) patients.
 At the endocardial stage, electrophysiological studies (EFI) were performed to clarify the mechanism of arrhythmia, and ablation eliminated tachyarrhythmia. EFI protocol: revision of the pulmonary veins, determination of the isolation of the posterior wall of the LA assessment of atrial arrhythmia, elimination of arrhythmia, control induction of arrhythmia after ablation. After repeated intervention, patients were observed in the operating clinic every 3 months.
 RESULTS: After the endocardial stage, a regular rhythm was determined in 19 (82.6%) patients of the BA group, 13 (92.9%) patients of the LA group (p = 0.914). Relapses in the form of AF were noted in 5 patients (4 — group 1 and 1 — group 2) group (p = 0.306) All relapses of tachyarrhythmia with an irregular cycle (AF) were detected in patients with AF before the endovascular stage In both groups, there were cases of restoration of conduction in the pulmonary veins — 10 (43.5%) patients after BA ablation and 1 (5.3%) patient after LA ablation. There are no recurrences of atrial arrhythmia after ablation of atrial flutter (arrhythmia with a stable cycle).
 CONCLUSION: The endocardial stage is highly effective and demonstrates subsequent freedom from atrial arrhythmia in patients who have tachycardia with a regular cycle after both methods of surgical ablation of AF. Recurrent tachyarrhythmia in the form of AF (irregular cycle) is associated with a low probability of maintaining a regular atrial rhythm after a repeated endocardial procedure, due to the presence of structural and electrophysiological changes in the atrial myocardium.

Abstract 18136: Efficacy and Safety of Catheter Ablation for Atrial Arrhythmias in Patients With Cardiac Amyloidosis - A Systematic Review and Proportional Meta-Analysis

Background Cardiac amyloidosis (CA) is a restrictive cardiomyopathy characterised by amylin deposits in the heart muscle. While the prevalence of atrial arrhythmias in CA is high, the data regarding the outcomes of catheter ablation in these patients is limited. Our current study aims to elucidate the safety & efficacy of catheter ablation for treating atrial arrhythmias in patients with CA. Methods: We conducted a comprehensive literature search across MEDLINE & Scopus from inception till May 2023 for randomized control trials & observational studies reporting catheter ablation (cryoablation or radiofrequency ablation) for the treatment of atrial arrhythmias (AAs) (atrial flutter, atrial fibrillation, atrial tachycardia) in patients with cardiac amyloidosis (transthyretin or light-chain). The primary outcomes of interest were pooled recurrence & re-ablation rates. The secondary outcome was all-cause mortality. All data was analyzed using the Hedges-Olkin random-effects model & presented as percentage proportions. Results: A total of 6 cohort studies with 154 cardiac amyloidosis patients with atrial fibrillation were included. The pooled incidence of repeat ablation was 16.4% [(6.2%, 26.7%), p=0.002)] & recurrence rate was 47.9% [(25.2%, 70.5%), p<0.001)]. The pooled incidence of all-cause mortality in these patients was 37.1% [(25.1%, 49.1%), p<0.001)]. Conclusion High rate of recurrence & need for re-ablation coupled with high mortality demands better patient selection. Prospective & randomized controlled data is needed to better study the outcomes of catheter ablation in these patients.

Prevalence of metabolic syndrome and its association with atrial arrhythmias in patients with implanted permanent pacemaker for cardiac conduction abnormality

The objective of the study was to find the prevalence of metabolic syndrome along with identifying the atrial arrhythmias, QTC interval, and coronary artery disease among these patients during follow-ups. Among 171 subjects who were implanted with permanent pacemakers, metabolic syndrome was present in 90 (52.6 %). Prevalence of Arrhythmias was 49 (28.7 %), atrial tachycardia (AT)/atrial fibrillation (AF) was seen in 29 (17 %) patients. Our study showed that there is a strong association between metabolic syndrome and atrial arrhythmias. Metabolic syndrome, age, coronary artery disease and Systolic blood pressure were good independent predictors of atrial arrhythmias among patients with pacemaker implantation.

Incidence of Documented Atrial Arrhythmias in Patients with Dual Chamber Cardiac Implantable Devices

Abstract Background Atrial fibrillation (AF) is the most common sustained atrial arrhythmia, and is associated with increased risks of morbidity and mortality. Integrated management including anticoagulation therapy in patients with AF is increasingly recognized, but there are still a substantial number of AF patients admitted with stroke, heart failure, and other complications. This can be to some extent due to asymptomatic nature of AF as approximately one-third of patients did not report any symptoms commonly attributable to AF (e.g., palpitations, shortness of breath, or chest pain), leading to a prolonged delay in AF diagnosis and timely initiation of anticoagulation therapy. In many cases, asymptomatic AF is diagnosed only after the onset of complications such as ischemic stroke or congestive heart failure has occurred. Objective This work aims at documenting atrial arrhythmias in patients with dual chamber cardiac implantable devices. Patients and Methods This study included 200 patients who were undergoing follow up of dual chamber cardiac implantable devices. The study was carried out in pacemaker follow up clinics at Ain Shams University hospitals and National Heart Institute. Results According to the results of the current study we concluded diabetes Mellitus, ischemic heart diseases, decreased function (EF ≤ 48%) and dilated LA & LV dimensions (LVIDd >48 mm, LVIDs >41 mm, LA diameter >52 mm), are significant factors associated with AHREs in patients with dual chamber cardiac implantable devices. But unfortunately we cannot assess precisely the impact of AHRE on stroke or thromboembolism development in such patients due to the relatively small number of patients were included in the present study, which may have reduced the detection power and possibly influenced the validity of some results. Conclusion Diabetes Mellitus, ischemic heart diseases, decreased function (EF ≤ 48%) and dilated LA & LV dimensions (LVIDd >48 mm, LVIDs >41 mm, LA diameter >52 mm), are significant factors associated with AHREs in patients with dual chamber cardiac implantable devices. Abbreviations AF: Atrial fibrillation; AHRE: Atrial high rate episodes; AT: Atrial Tachycardia; BMI: Body mass index; CI: Confidence intervals; CIED: Cardiac implantable electronic devices; CRT: Cardiac resynchronization therapy; DDD: Dual chamber Device DM: Diabetes Mellitus; ECG: Electrocardiogram; EF: Ejection Fraction; HbA1c: Hemoglobin A1c; HR: Hazard Ratio; ICD: Implantable cardioverter defibrillator; IHD: Ischemic heart disease; INR: International Normalized Ratio; LA: Left atrium; LVIDd: Left ventricular internal dimensions (Diastole); LVIDs: Left ventricular internal dimensions (Systole); MOST: Mode Selection Trial; OR: Odds ratio; ROC: Receiver operating characteristic curve; AUC: Area Under Curve; SCAF: Subclinical AF

Atrial Arrhythmias in Adults with Fontan Palliation.

Single ventricle physiology is a rare form of congenital heart disease and was, historically, a uniformly lethal condition. However, the atriopulmonary Fontan operation, and its successive iterations, the lateral tunnel and extracardiac conduit Fontan, became the fundamental approach to treating single ventricle heart disease. Over time, dysrhythmias are some of the most common complications with Fontan physiology, compounding morbidity and mortality. Atrial arrhythmias are prevalent in the Fontan population and occur in about 15-60% of patients with Fontan palliation, increasingly with age. Diagnosing atrial arrhythmias in patients with Fontan palliation may be challenging because of low voltage amplitudes arising from myopathic atrial tissue making it difficult to clearly assess atrial depolarization on surface electrocardiograms (ECG), vague symptoms not suggestive of tachyarrhythmia, or atrial arrhythmia with ventricular rates below 100beats per minute. Intra-atrial reentrant tachycardia (IART) is the most common type of supraventricular tachycardia in adults with Fontan palliation. Acute management of atrial arrhythmias in patients with Fontan palliation involves prompt assessment of a patient's hemodynamic stability, anticoagulation and thrombosis risk, systemic ventricular function, and risk of sedation or anesthesia if needed. Long-term management of atrial arrhythmias is often multifactorial and may include long-term anti-arrhythmic therapy, permanent pacing, and ablation. The best approach for the management of atrial arrhythmias in adults with Fontan palliation is patient-specific and involves collaboration between congenital electrophysiologists, adult congenital cardiologists, and the patient.

Different electrophysiological characteristics of cavo-tricuspid isthmus dependent atrial flutter guided by robotic magnetic navigation in patients with and without prior cardiac surgery.

Cavo- tricuspid isthmus dependent atrial flutter (CTI- AFL) is a common atrial arrhythmia in patients with prior cardiac surgery (postsurgical AFL) and without prior cardiac surgery (nonsurgical AFL). However, there is only limited data regarding the eletrophysiological differences between the CTI- AFL in the postsurgical patients and the nonsurgical patients. We aimed to investigate the differences in clinical and electrophysiological characteristics between the postsurgical group and nonsurgical group and to evaluate the acute and long-term outcomes after ablation guided by robotic magnetic navigation (RMN) in both the groups. Methods Fourty-two consecutive patients with nonsurgical AFL and 21 with postsurgical AFL were retrospectively analyzed in our center. Electrocardiographic (ECG) analysis and three-dimensional electrophysiological study were performed in all the patients. The results revealed that only 55.6% of postsurgical patients with proven counterclockwise (CCW) AFL presented with a typical ECG suggesting this mechanism. In contrast, 86.1% of nonsurgical patients demonstrated a typical ECG pattern for CCW AFL. In addition, we employed a reverse "U-curve" to facilitate radiofrequency delivery when ablating near the inferior vena cava ostium in the present study. Compared with the nonsurgical group, electroanatomical mapping showed the mean AFL cycle length was significantly longer (253.3 ± 40.4 vs. 234.1 ± 24.2 ms, p = 0.03) and the right atrium volume was larger (114.8 ± 26.0 vs. 97.5 ± 19.1 mL, p = 0.004) in the postsurgical group. Additionally, the procedural time (75.9 ± 21.3 vs. 61.6 ± 26.6 minutes, p = 0.03) and ablation time (53.0 ± 21.4 vs. 36.7 ± 25.6 minutes, p = 0.02) are much longer in the postsurgical group. However, the navigation index in the postsurgical group was significantly smaller (0.35 ± 0.08 vs. 0.43 ± 0.13, p = 0.01). Moreover, the acute and long-term success rates were comparable between the two groups. Catheter ablation of CTI-AFL with and without prior cardiac surgery guided by RMN are associated with high acute and long-term success rates, despite the procedural and ablation times are much longer in the postsurgical patients. However, ECG characteristics of the tachycardia may be misleading as they are more often atypical in patients after cardiac surgery.

The Importance of a Distance between the Lines Encircling Pulmonary Veins in Atrial Fibrillation Ablation on First-Pass Isolation Ratio and Clinical Outcomes.

How wide the encircling line is made may influence the outcomes of pulmonary vein isolation (PVI). In the present study we hypothesised that the distance between the lines encircling the pulmonary veins may correspond with the extent of wide antral circumferential ablation (WACA). The aim of the study was to assess the impact of the distance and the area between the lines on the posterior wall of the left atrium on first-pass isolation rate and 12-month freedom from atrial arrhythmia in patients undergoing PVI ablation. One hundred sixteen patients underwent circumferential ablation index (AI)-guided PVI. The distance between the encircling ablation lines was measured off-line between the uppermost points (right and left) and the lowest points and as the area between the encircling lines on the posterior wall. The first-pass isolation rate and 12-month freedom from atrial arrhythmia were 59% and 73%, respectively. Distance between the encircling lines measured linearly or as the area of the posterior wall, assessed as direct values or indexed to left atrial dimensions, did not differ between patients with and without first-pass isolation or between patients with and without recurrences of atrial arrhythmia. The distance between the ablation lines did not influence the rate of first-pass isolation and arrhythmia recurrence in the long-term follow-up after PVI procedures incorporating the ablation index protocol.

Abstract 11477: Assessing New Onset of Atrial Arrhythmia in Patients Undergoing Alcohol Septal Ablation for Hypertrophic Obstructive Cardiomyopathy

Introduction: Alcohol septal ablation (ASA) is an effective percutaneous procedure used to treat refractory hypertrophic obstructive cardiomyopathy (HOCM). ASA relieves left ventricular outflow tract (LVOT) obstruction by creating a targeted infarction in the septal muscle. Diastolic dysfunction and mitral regurgitation are responsible for increased left atrial pressure which contributes to left atrial ectopy. We seek to assess the incidence of atrial arrhythmias post-ASA and identify predictors to risk stratify these patients. Methods: Using a patient database maintained internally, 144 consecutive patients who underwent ASA for HOCM between March 2017 and February of 2022 at MUSC were retrospectively reviewed. Patients were selected based on the need for cardiac event monitoring after ASA. Patients were retrospectively analyzed for a previous history of atrial fibrillation (AF) as well as a new onset of AF after ASA. SPSS statistics was used for statistical analysis. Results: A total of 31 patients met final inclusion criteria. During the monitored time, seven patients (22.58%) developed a new onset of AF after ASA. Patients who developed AF post-ASA were found to have a statistically higher left atrial end-systolic volume index (LAESVi, mL/m 2 ) and left ventricular end-diastolic pressure (LVEDP, mmHg) (59.96 ± 8.93, 34.33 ± 11.54) when compared to those who did not develop AF (41.13 ± 13.93, 23.33 ± 9.06 (p=0.0003, p=0.0331)). Conclusions: In this high-risk proportion of patients who required cardiac monitoring post-ASA, there is a higher-than-expected risk for new onset of AF. The left atrial size and left ventricular filling pressures before ablation were the only significant predictors for development of atrial arrhythmias after ASA. Longer-term evaluation will be able to address if the expected reduction in atrial size and LVOT gradient after ASA will reduce the overall long-term burden of atrial arrhythmias.

SIOG2022-0203 - Radiation Induced Atrial Arrhythmias in patients with Lung Cancer: A population-based study

SIOG2022-0203 - Radiation Induced Atrial Arrhythmias in patients with Lung Cancer: A population-based study

Outcomes of Radiofrequency Catheter Ablation of Atrial Arrhythmias in Patients with Cardiac Amyloidosis

Outcomes of Radiofrequency Catheter Ablation of Atrial Arrhythmias in Patients with Cardiac Amyloidosis

Correlation of 24-Hour Urinary Microalbumin and Atrial Arrhythmia in Patients With Essential Hypertension

Abstract Background To investigate the relationship between 24-hour urinary microalbumin (24h-UmAlb) and atrial arrhythmia in patients with essential hypertension (EH). Methods From March 2018 to January 2020, 917 EH patients at First Affiliated Hospital of Xinjiang Medical University were enrolled, and divided into nonatrial arrhythmia and atrial arrhythmia groups according to their 24-hour dynamic electrocardiography. The general clinical data and laboratory test parameters were compared. Results Compared with patients without atrial arrhythmia, the 24-UmAlb level was higher in patients with atrial arrhythmia (8.0, 5.0–19.7 vs. 7.5, 4.5–15.5 mg/24 hours, Z = −2.190, P < 0.05). Multivariate regression analysis showed that positive 24-UmAlb (odds ratio = 1.649, 95% confidence interval 1.065–2.554) and supine angiotensin II (odds ratio = 1.407, 95% confidence interval 1.034–1.914) were the risk factor for atrial arrhythmia in patients with EH after adjusted for left atrial diameter, age, course of hypertension, 24-hour systolic and diastolic blood pressure. Conclusions 24h-UmAlb is one of the risk factors for atrial arrhythmia in patients with EH.

Atrial arrhythmias in patients beyond 40 Years of age post atrial septal defect device closure

BackgroundPatients >40 years with an atrial septal defect (ASD) may have atrial arrhythmia which warrants treatment. It is unclear whether preventive left atrial appendage (LAA) occlusion should be performed simultaneously during ASD closure in these patients. ObjectiveThis study aimed to examine the incidence of de novo atrial arrhythmia in patients >40 years old post transcatheter closure of ASD. MethodsThis was a single-center, retrospective study involving all consecutive patients who have undergone device closure of ASDs at age >40 years. Standard 12-lead ECGs were performed pre-procedure and during every clinic follow-up. Ambulatory monitors were applied when indicated. ResultsEighty-eight patients (mean age: 51.81 ± 8.01 years; male: 22.7%) were recruited and followed up over a median duration of 3.6 years (range: 1–6.5). Seven patients (8%) had documented atrial arrhythmia (AA) pre and post ASD closure. Two patients (2.5%) developed de novo atrial fibrillation and one patient (1.2%), ectopic atrial rhythm during follow-up. In univariate analyses, age >61.3 years (p < 0.001), a history of palpitation (p = 0.006), right atrial area >25.15cm2 pre-closure (p = 0.004); dilated right and left atrium immediately post ASD closure (p = 0.016 & 0.001) and pulmonary vascular resistance >1.31Woods unit (p = 0.036) were associated with increased risk of AA. However, on multivariate analyses, none were significantly associated with AA. ConclusionsDe novo atrial arrhythmia after ASD device closure is uncommon.

Targeted cluster ablation of non-CTI-dependent atrial arrhythmias in congenital heart disease using ultrahigh-definition mapping.

Ablation of atrial arrhythmias in patients with congenital heart disease (CHD) has markedly improved with advanced mapping systems. However, recurrence rates remain high. The linear ablation strategy is not uncommonly practiced necessitating prolonged ablation times. We report the outcomes of adopting a strategy of minimal, cluster delivery of radiofrequency (RF) energy at critical substrates identified by ultrahigh-definition mapping for atrial arrhythmias in patients with CHD. Non-cavotricuspid isthmus (non-CTI) atrial tachycardias were ablated with a targeted ablation cluster technique (TACT) using an ultrahigh-density mapping system combined with multielectrode monitoring and endpoint determination in preference to linear ablation. The arrhythmia substrates, RF times, and acute- and medium-term success rates were studied. Fifty-eight tachycardias were mapped and ablated in 42 procedures: 34 non-CTIs and 24 CTIs. A targeted ablation cluster was performed for non-CTI tachycardias, with a median ablation time of 3.1 min. In 53% of non-CTI tachycardias, arrhythmia termination was achieved with ≤2 RF applications. After a mean follow-up of 23.6 months, 27 (80%) patients were free of recurrent atrial arrhythmias. One of 34 targeted non-CTI tachycardia recurred, with a final success rate of 91%. Linear ablation was performed for CTI flutters with a median ablation time of 6.8 min (vs. non-CTIs, p = .006). Three of 21 tachycardias recurred due to reconnection of the ablation line but the final success rate was 100%. The TACT approach for non-CTI atrial arrhythmias in congenital patients as guided by theultrahigh-density mapping is an effective method with short ablation times and excellent medium-term outcomes.

Incidence, Risk Factors, and Outcomes of Atrial Arrhythmias in Adult Patients With Atrioventricular Septal Defect.

This study aimed to assess the incidence, associated factors, and outcomes of atrial arrhythmias in adults with atrioventricular septal defect (AVSD). Data regarding atrial arrhythmias in adults with AVSD are particularly scarce. Data were analyzed from a multicentric cohort of adult patients with AVSD. Lifetime cumulative incidences of atrial arrhythmias were studied. Multiple logistic regression models were used to identify risk factors. A total of 391 patients (61.6% women) were enrolled with a mean age of 36.3 ± 16.3 years and a mean follow-up of 17.3 ± 14.2 years after initial surgical repair. Overall, 98 patients (25.1%) developed at least 1 episode of atrial arrhythmia at a mean age of 39.2 ± 17.2 years. The mean ages of patients at first episode of intra-atrial re-entrant tachycardia (IART)/ focal atrial tachycardia (FAT) and atrial fibrillation were 33.7 ± 15.3 and 44.3 ± 16.5 years, respectively. The lifetime risks for developing atrial arrhythmia to ages 20, 40, and 60 years were 3.7%, 17.8%, and 55.3%, respectively. IART/FAT was the leading arrhythmia until the age of 45, then atrial fibrillation surpassed IART/FAT. Age (odds ratio [OR]: 1.4; 95% confidence interval [CI]: 1.2-1.6), number of cardiac surgeries (OR: 4.1; 95%CI: 2.5-6.9), left atrial dilatation (OR: 3.1; 95%CI: 1.4-6.8), right atrial dilatation (OR: 4.1; 95%CI: 1.7-10.3), and moderate or severe left atrioventricular valve regurgitation (OR: 3.7; 95%CI: 1.2-11.7) were independently associated with a higher risk of atrial arrhythmias, whereas the type of AVSD and the age at repair were not. The occurrence of atrial arrhythmias was associated with pacemaker implantation (41.8% vs. 8.5%; P< 0.001), heart failure (24.5% vs. 1.0%; P< 0.001), and cerebrovascular accidents (11.2% vs. 3.4%; P = 0.007). The lifetime risk of atrial arrhythmias in patients with AVSD is considerable with more than half of patients developing≥1 atrial arrhythmia by the age of 60 and is associated with a significant morbidity. The risk in partial/intermediate AVSD is as high as in complete AVSD and is not impacted by age at repair.

Pre-existing cardiovascular disease increases risk of atrial arrhythmia and mortality in cancer patients treated with Ibrutinib

BackgroundIbrutinib is a Bruton’s tyrosine kinase inhibitor used in the treatment of hematological malignancies. The most common cardiotoxicity associated with ibrutinib is atrial arrhythmia (atrial fibrillation and flutter). It is known that patients with cardiovascular disease (CVD) are at an increased risk for developing atrial arrhythmia. However, the rate of atrial arrhythmia in patients with pre-existing CVD treated with ibrutinib is unknown.ObjectiveThis study examined whether patients with pre-existing CVD are at a higher risk for developing atrial arrhythmias compared to those without prior CVD.MethodsA single-institution retrospective chart review of patients with no prior history of atrial arrhythmia treated with ibrutinib from 2012 to 2020 was performed. Patients were grouped into two cohorts: those with CVD (known history of coronary artery disease, heart failure, pulmonary hypertension, at least moderate valvular heart disease, or device implantation) and those without CVD. The primary outcome was incidence of atrial arrhythmia, and the secondary outcomes were all-cause mortality, risk of bleeding, and discontinuation of ibrutinib. The predictors of atrial arrhythmia (namely atrial fibrillation) were assessed using logistic regression. A Cox-Proportional Hazard model was created for mortality.ResultsPatients were followed for a median of 1.1 years. Among 217 patients treated with ibrutinib, the rate of new-onset atrial arrhythmia was nearly threefold higher in the cohort with CVD compared to the cohort without CVD (17% vs 7%, p = 0.02). Patients with CVD also demonstrated increased adjusted all-cause mortality (OR 1.9, 95% CI 1.06-3.41, p = 0.01) and decreased survival probability (43% vs 54%, p = 0.04) compared to those without CVD over the follow-up period. There were no differences in risk of bleeding or discontinuation between the two cohorts.ConclusionsPre-existing cardiovascular disease was associated with significantly higher rates of atrial arrhythmia and mortality in patients with hematological malignancies managed with ibrutinib.

Abstract 12187: Arrhythmia Substrate and Approaches for First-Time and Repeat Catheter Ablation in Patients With D-transposition of the Great Arteries and Atrial Baffles

Introduction: Atrial arrhythmias are common in patients with D-TGA and atrial switch. We sought to analyze the arrhythmia substrate and catheter ablation approaches and outcomes. Methods: We performed a retrospective review of all clinical and procedural data in patients with D-TGA followed at a large tertiary care center. Results: In a cohort of 152 patients (mean age 30±11 years), atrial tachycardia was present in 69(45%) patients. Ablations were performed in 39(26%) patients: macro-reentrant atrial flutter (N=37), atrial fibrillation (N=4), and focal automatic atrial tachycardia (N=3). Detailed electrophysiology study data was available for 34 patients. At first ablation (N=28), cavo-tricuspid isthmus dependent flutter (CTI, 23(82%)) was most common, followed by right atriotomy-related flutter (IART, 16(57%)) and focal atrial tachycardia (FAT, 1(3.5%)). Bidirectional CTI block often required ablation on both sides of the baffle to complete the isthmus line. Access to the pulmonary venous atrium was obtained in 82% of first-time ablations (via retrograde aortic access, 74%, baffle puncture, 6%, or baffle fenestration, 12%) and in 100% of redo procedures. The first ablation was acutely successful in 25 (89%) patients; the other 3 patients had either partial procedural success (1), failed ablation (1), or underwent an empirical ablation (1). Long-term arrhythmia recurrence occurred in 13(46%) after the first ablation and class III antiarrhythmic medications were utilized in 12 patients. At least one long-term recurrence occurred in 11(44%) patients. Importantly, clinical arrhythmia burden was significantly reduced post-ablation, with rare and short-limited episodes amenable to antiarrhythmic drugs or cardioversion. Repeat ablation was required in 3 cases. Long-term arrhythmia recurrence after a previously completed CTI line involved different arrhythmia mechanisms: scar-related reentry (80%) and automatic atrial tachycardia (40%). Conclusions: Atrial arrhythmia in patients with D-TGA often involves the CTI and atriotomy scars. Ablation of the CTI typically requires access to the pulmonary venous atrium to achieve bidirectional block. Despite late recurrence, the clinical arrhythmic burden is substantially improved.

Abstract 12754: Is an Induction Test Necessary While Catheter Ablation of Atrial Fibrillation

Introduction: In general, several reports have been that it is beneficial to confirm the induction test of atrial arrhythmias by burst and provide additional procedures after catheter ablation (CA) for atrial fibrillation (AF). However, few reports on whether the presence or absence of an induction test of arrhythmia affects long-term recurrence. Hypothesis: In this study, we sought to elucidate the relationship between induction test and recurrence of atrial arrhythmias in patients who underwent CA for AF. Methods: We enrolled 678 consecutive patients who underwent the first CA for AF from 2014 to 2020. Of all patients, 573 patients (85%) were performed induction test during CA. After propensity score matching with factors that may affect recurrence i.e., age, left atrial diameter, gender, disease type, and history of coronary artery disease, we divided into induction group (n = 104) and non-induction group (n = 104). The primary endpoint was the recurrence of AF and the occurrence of other atrial tachy-arrhythmias after the 90-day blanking period. The observational period was set at one year after the index. Results: The median age was 67 (59 - 73) years old with 22% of female. During the periods, the recurrence occurred in 46 (22%) patients. In the log-rank test, there was no significant difference in the recurrence rate between the two groups (P = 0.74). Conclusions: The induction test might not be required for atrial fibrillation ablation; however, we will need a prospective study in the future.