Successful Catheter Ablation Research Articles

SIMULATION OF PREMATURE VENTRICULAR CONTRACTIONS IN PATIENT SPECIFIC BIDOMAIN VENTRICULAR MODEL

The goal of the study was to simulate electrical activation of the heart ventricles and corresponding body surface potentials (BSPs) during premature ventricular contractions (PVC) using the patient specific realistic homogeneous model of cardiac ventricles and the torso. Real position of the initial ectopic activation during PVC was determined by intracardial measurement in the upper part of the right ventricle near the His bundle and confirmed by successful catheter ablation of the PVC origin. Simulated electrical activation in the ventricular model was started at the position of the initial ectopic activation as well as at several other sites at various distances from this position. The propagation of electrical activation in the ventricular model was modeled using bidomain reaction-diffusion (RD) equations with the ionic transmembrane current density defined by the modified FitzHugh-Nagumo (FHN) equations. The torso was modeled as a homogeneous passive volume conductor. The RD equations were numerically solved in the Comsol Multiphysics environment. Simulated ECG signals and BSPs were compared with those measured during PVC in a real patient. The polarity and shape of simulated and measured ECG leads as well as the BSP distribution during the PVC were in best agreement when the stimulated region was less than 10 mm from the position of the initial ectopic activation.

Dipole Density Guided Catheter Ablation versus Conventional Substrate Modification for Repeat Catheter Ablation of Persistent Atrial Fibrillation.

The optimal ablation strategy for recurrent persistent atrial fibrillation (persAF) after initially successful catheter ablation (CA) remains debatable. Dipole density (DD) guided CA using the AcQMap system has been proven to be feasible and effective in patients with persAF. So far, long-term outcome data for DD-guided CA in patients with recurrence of persAF are sparse. This study sought to assess long-term outcome data in patients undergoing a DD-guided CA for recurrence of persAF after previous CA in comparison to conventional repeat CA. Patients undergoing DD-guided CA for recurrence of persAF after previous ablation were compared to patients undergoing conventional substrate modification (CSM). A total of 64 patients (32 DD-guided and 32 CSM) were included in this analysis. Procedure duration (DD: 236 ± 61 min; CSM: 198 ± 59 min; p = 0.004) and fluoroscopy time (DD: 36 ± 15 min; CSM: 20 ± 11 min; p = 0.0001) were significantly longer in the DD group. After a long-term median follow-up (FU) of 27 months (interquartile range 12.8-34.3), DD-guided CA was inferior to CSM regarding overall arrhythmia-free survival (DD: 6 patients (19%), CSM: 11 patients (34%); HR 1.47; p = 0.04). Freedom from AF did not differ between both groups (DD: 16 patients (50%); CSM: 18 patients (56%), HR 0.99, p = 0.47). During FU, more patients underwent repeat CA after DD-guided ablation (DD: 16 patients (50%), CSM: 7 patients (22%), p = 0.04). No major complications occurred overall. Dipole density-guided CA is equally safe but associated with longer procedure duration compared to conventional substrate modification for treatment of recurrent persAF after previous CA. Of note, long-term arrhythmia-free survival is significantly worse after DD-guided ablation, and more patients undergo redo procedures.

Successful high-resolution three-dimensional electroanatomical mapping and radiofrequency catheter ablation of a posteroseptal accessory pathway in a dog using CARTO 3

A one-year-and-seven-month-old, 28 kg, male castrated crossbreed dog was presented for supraventricular tachycardia causing recurrent episodes of anorexia and lethargy. Sotalol (2.2 mg/kg q12 h) reduced the frequency of symptomatic episodes but did not provide full relief. Three-dimensional electroanatomical mapping was performed at the Ghent University Small Animal Teaching hospital using the CARTO 3. Right atrial activation mapping identified the earliest atrial activation right posteroseptal, near the tricuspid annulus. Fast retrograde ventriculoatrial conduction during tachycardia and extrastimulus testing confirmed the presence of a concealed right posteroseptal accessory pathway. Six radiofrequency catheter ablation applications were delivered, and tachycardia remained uninducible. The dog recovered well from the procedure. Sotalol was stopped three weeks later, and no more clinical signs were noted by the owner. Repeated 24-hour electrocardiography monitoring on day one and at one, three, and 12 months after the procedure showed no recurrence of tachycardia.

Improved 1-year success of catheter ablation for persistent atrial fibrillation with vein of Marshall ethanol infusion: A large observational study

Improved 1-year success of catheter ablation for persistent atrial fibrillation with vein of Marshall ethanol infusion: A large observational study

Combining 3D SONAR with High Resolution Imaging to Improve Vision in Atrial Fibrillation Ablation

Real-time, accurate imaging of improperly functioning tissue that causes atrial fibrillation (AF) is essential for successful catheter ablation procedures. Ablation procedures and success rates may be improved by overlaying intracardiac echocardiography with high resolution cardiac imaging. Data extracted from previous research reports that current pharmacological agents do not address the principal cause of AF. Unlike medication, catheter ablation resolves the issue by treating AF’s source. Therefore, catheter ablation is the better alternative. However, while catheter ablation is preferable to medication, the detail and accuracy of anatomical visualizations used to guide the catheter can be inconsistent. While real time guidance technology updates, the visibility quality is limited. However, detailed preliminary imaging does not accurately reflect the latest changes. This paper discusses the current limitations of catheter ablation and proposes real-time three-dimensional Sound Navigation and Ranging (SONAR) imaging paired with high-resolution cardiac Magnetic Resonance Imaging (MRI) as a novel tool to improve live-imaging localizations and resolution for cardiac ablation procedures.

Assessment of left atrial fibrosis by 18F-FDG PET/CT in persistent atrial fibrillation : comparison to electroanatomical mapping and cMR late gadolinium enhancement

Abstract A wide body of evidence suggests that left atrial (LA) interstitial fibrosis is a key contributor to persistent atrial fibrillation (peAF) and that its extent is predictive of the success of catheter ablation (CA) for this condition. Late gadolinium enhanced magnetic resonance imaging (LGE-cMR) has become increasingly popular for non-invasive detection and quantification of atrial fibrosis prior to CA. However, it is limited by a high rate of suboptimal scans and by large variability of quantification of fibrosis. We recently described the ability to obtain high quality 18- fluorodeoxyglucose (FDG) positron emission tomography (PET) of the atria after acipimox administration, and hypothesize that, similar to the left ventricle (LV), atrial metabolic activity could be a marker of cellular viability, indicating the absence of atrial fibrosis. The objective of our study was to investigate the potential utility of 18FDG uptake in the LA as an indicator of atrial scar and a predictor of CA success in patients with peAF. To this end, we compared the LA 18FDG uptake to LA voltage mapping during electrophysiological studies (EP) and cMR-LGE as a reference standard. Method 33 nondiabetic patients with nonvalvular peAF hospitalized for a first CA in our center prospectively underwent 18FDG-PET/CT, and LGE-CMR prior to EP and CA procedures. FDG-PET, LGE-cMR and electoanatomical maps were segmented and corregistrated in 3D surface models based on anatomical information from the contrast enhanced cMR angiograms. For 18FDG-PET/CT, maximum intensity projection of standardized uptake values (SUVs) along the surface was calculated and abnormal low metabolism was identified using a threshold of four standard deviations below the average SUV value of the atrial blood. Electrical scarring on EP voltage maps was defined as bipolar measurements of < 0.3 mV in AF, while fibrosis by LGE-CMR was evaluated using several thresholds of 2-5 standard deviations above the average blood signal intensity and the average intensity of the enhancement around the mitral valve. All three parameters of scar were expressed in percentage of the total LA area. Results Atrial hypometabolism by FDG-PET correlated strongly with electrical scaring by low voltage area during EP study (p<0.001, R² = 0.573). Atrial wall mean SUV standardized by LV uptake was also associated with low voltage, also the association's strength was mild (p =0.012, R²=0.22). There was good spatial corregistration of areas of low FDG metabolism with low voltage areas during EP study (Figure 2). By contrast there was no association between PET and LGE-cMR and association between atrial LGE by cMR and atrial voltage for all used thresholds. Conclusion Low 18FDG uptake by PET/CT showed a good correlation with atrial electrical scaring, while LGE-CMR did not. Our data suggest that atrial FDG PET could therefore be a valuable technique for non-invasive evaluation of atrial fibrosis prior to CA.Low metabolism versus low voltageMetabolic and voltage maps

Abstract 12947: Restoration of Sinus Rhythm Significantly Improves Left Ventricular Function in Patients With Very Low Ejection Fraction

Introduction: Left ventricular (LV) dysfunction is a common sequelae of supraventricular tachycardia, especially atrial fibrillation (AF). We evaluated the impact of restoration of sinus rhythm following successful catheter ablation on LV function in AF patients with ejection fraction of ≤20%. Methods: Consecutive AF patients with LVEF ≤20% undergoing their first catheter ablation were included in the study. All received isolation of pulmonary veins, left atrial posterior wall and superior vena cava. Additionally, non-PV triggers were ablated at the operator’s discretion. Echocardiogram was performed at baseline and 6 months post-ablation to measure the LVEF. Arrhythmia-monitoring was performed at 1, 3 and 6 months with event recorders, 12-lead ECG and 7-day Holter monitoring. Results: A total of 63 patients undergoing catheter ablation for AF were included (age: 62.5 ± 9.9 years, male: 82.5%). Majority of the patients had LVEF of ≤15% (n=48, 76%); remaining 15 patients had LVEF of 16-20%. Mean LA diameter was 4.94 ± 0.57 cm and 82.5% of patients had non-paroxysmal type of AF. Median duration of AF was 27 months. Follow-up echocardiogram at 6 months of follow-up detected significant improvement in LVEF [Mean difference: 15.2 ± 11.7% (p < 0.001)]. All patients were arrhythmia-free at that time point: 47 (74.6%) off-drugs and 16 (25.4%) patients on previously ineffective anti-arrhythmic drugs. Conclusion: Restoration of sinus rhythm following successful catheter ablation was associated with significant improvement in LVEF in patients with severe LV dysfunction

Abstract 12182: Importance of Comorbidities in 24-month AF-Free Survival After Catheter Ablation

Background: Presence of cardiac and non-cardiac comorbidities is reported to affect success of catheter ablation (CA) of atrial fibrillation (AF), however their predictive value in 1 and 2 year AF free survival is not reported. Research Questions: Which cardiac and non-cardiac comorbidities are most useful in predicting AF free survival after a single CA for paroxysmal and persistent AF. Goals: Create a model to identify potential risk factors that may reduce the long term success of catheter ablation for patients with AF to allow for risk modification Methods: We included 1435 patients with symptomatic AF undergoing first time CA in 1 of 8 Hospitals of Northwell Health and follow ups for at least 24 months ablation. Baseline echocardiographic and laboratory data were extracted from our common EMR, and clinical outcomes were determined after manual review of the 6, 12 and 24 month visit. Baseline patient characteristics included age, gender, BMI, diagnoses, laboratory and echocardiographic measures used in a stepwise estimation logistic regression model using STATA /IC 16.1. Results: From our patient cohort (age 67.1±10.4, 565 female, 645 persistent), 28% of patients had AF recurrence within the 1st year, and 32.5% within 2 years. Multivariate analysis identified persistent AF as the only independent risk factor for AF recurrence within 12 months (P=.001). For 24-month recurrence the independent predictors were LVEF (p=.014), Diabetes Mellitus (p=.045), cardioversions prior to ablation (DCCV) (p=.001), and pulmonary disease (p=.001). Energy modality was not a significant predictor of AF recurrence. Hypertension (p=.008) was found to be negatively associated with AF recurrence. Our prediction model (Figure 1) for AF recurrence 24 months post-CA produced an ROC curve of 0.8048 and was 77% accurate. Conclusion: The presence of baseline comorbidities implies that such comorbidities, rather than procedural failure, are mostly related with AF recurrence after 1 year.

Abstract 17188: Electrocardiographic Algorithms for Localization Ventricular Ectopy From the Ventricular Outflow Tracts Demonstrate Poor Accuracy and Agreement

Background: Premature ventricular contractions (PVCs) and ventricular tachycardia (VT) commonly arise from the outflow tracts of the left and right ventricles and can be treated with catheter ablation when symptomatic or associated with cardiomyopathy. Accurate localization of these ectopic sources aids procedural planning. Several different electrocardiographic (ECG) algorithms have been published, but their relative performance has not been assessed. Objective: Compare the accuracy and agreement of three ECG algorithms for PVC localization. Methods: ECGs from patients who underwent catheter ablation for PVCs or VT originating the outflow tract region were analyzed using three published PVC localization algorithms. The predictions from these algorithms were then compared to the site of successful catheter ablation (right ventricular outflow tract [RVOT], left ventricular outflow tract [LVOT], or epicardium). The accuracy and agreement of the three algorithms were compared. Results: A total of 43 patients were evaluated and ectopy was suppressed via ablation from a single chamber in 37 (86%) of patients. VT/PVCs originated from the RVOT (N=10), LVOT (N=26), and epicardium (N=1). The three studied algorithms demonstrated accuracy rates of 46-70%. The algorithms disagreed on the predicted ectopy location for 19 (51%) patients. When all algorithms agreed (N=18), the prediction was accurate for only 11 patients (61%). Conclusion: Rules-based ECG algorithms demonstrate poor performance and use of different published algorithms frequently result in disparate results. More accurate and consistent methods incorporating individualized electroanatomic variation may improve accuracy and periprocedural management for PVC and VT ablation.

Prevention of cerebral thromboembolism by oral anticoagulation with dabigatran after pulmonary vein isolation for atrial fibrillation: the ODIn-AF trial

Background and objectivesLong-term oral anticoagulation (OAC) following successful catheter ablation of atrial fibrillation (AF) remains controversial. Prospective data are missing. The ODIn-AF study aimed to evaluate the effect of OAC on the incidence of silent cerebral embolic events and clinically relevant cardioembolic events in patients at intermediate to high risk for embolic events, free from AF after pulmonary vein isolation (PVI).MethodsThis prospective, randomized, multicenter, open-label, blinded endpoint interventional trial enrolled patients who were scheduled for PVI to treat paroxysmal or persistent AF. Six months after PVI, AF-free patients were randomized to receive either continued OAC with dabigatran or no OAC. The primary endpoint was the incidence of new silent micro- and macro-embolic lesions detected on brain MRI at 12 months of follow-up compared to baseline. Safety analysis included bleedings, clinically evident cardioembolic, and serious adverse events (SAE).ResultsBetween 2015 and 2021, 200 patients were randomized into 2 study arms (on OAC: n = 99, off OAC: n = 101). There was no significant difference in the occurrence of new cerebral microlesions between the on OAC and off OAC arm [2 (2%) versus 0 (0%); P = 0.1517] after 12 months. MRI showed no new macro-embolic lesion, no clinical apparent strokes were present in both groups. SAE were more frequent in the OAC arm [on OAC n = 34 (31.8%), off OAC n = 18 (19.4%); P = 0.0460]; bleedings did not differ.ConclusionDiscontinuation of OAC after successful PVI was not found to be associated with an elevated risk of cerebral embolic events compared with continued OAC after a follow-up of 12 months.Graphical abstract

Successful Supravalvular Radiofrequency Catheter Ablation of Premature Ventricular Contractions Originating From the Left Ventricular Summit

Successful Supravalvular Radiofrequency Catheter Ablation of Premature Ventricular Contractions Originating From the Left Ventricular Summit

Long-term results of catheter ablation for AV nodal reentry tachycardias and accessory pathways

Atrioventricular nodal reentrant tachycardia (AVNRT) and atrioventricular reentrant tachycardia in patients with accessory pathways (AP) are common supraventricular tachycardias. High long-term efficacy of about 97% (AVNRT) and 92% (AP) has been observed in children and adults. The risk of occurring atrioventricular block is low (0.4-0.8% during AVNRT, 0.1-0.2% for AP). Catheter ablation shows alower efficacy of 87-93% and elevated atrioventricular block risk up to 10% in patient groups with complex congenital heart disease. Nonsynchronized ventricular activation during preexcitation or permanent reentrant tachycardias can induce heart failure, and remission of left ventricular function can be expected in > 90% after successful catheter ablation. Therefore, catheter ablation is the long-term therapy of choice for AVNRT and AP with high efficacy and safety for most patient populations.

Accuracy of symptoms and pulse checking for detecting atrial fibrillation following catheter ablation.

There is growing interest in the possibility of discontinuing oral anticoagulation following successful catheter ablation of atrial fibrillation (AF). However, it remains unknown whether patients can accurately detect arrhythmia recurrences following ablation. We therefore sought to characterize the accuracy of pulse checking and arrhythmia symptoms for the identification of AF following ablation. This prospective cohort study included patients at the Hospital of the University of Pennsylvania with an insertable cardiac monitor (ICM) treated with catheter ablation for AF who recorded the results from minimum twice daily pulse checks and additionally with arrhythmia symptoms into a diary for 2 months following their procedure. Accuracy of this self-assessment protocol was determined by comparison to ICM-detected AF. A total of 55 patients (age 69 ± 8 years, 30 (55%) male, CHA2DS2VASc score 3.2 ± 1. 5) were included. Patients recorded a total of 5911 pulse checks, and there were 280 episodes of ICM-documented AF among 26 patients with an average duration of 2.5 ± 3.3 h. Among 362 episodes of patient-suspected AF, 134 correlated with ICM-identified AF (37% true positive rate). Of the 5549 pulse checks that did not identify AF, 196 correlated with ICM-identified AF (4% false negative rate). Twice daily pulse checking had a sensitivity of 47% and a specificity of 96% for identifying each episode of AF. Our data indicate that a strategy of pulse checks and symptom assessment is insufficient to identify all episodes of AF in many patients following catheter ablation.

Surgery for ventricular tachycardia originating from the left ventricular summit.

Ventricular tachycardia (VT) originating from the left ventricular summit region, the most superior region of the left ventricle surrounded by the major coronary arteries and veins, is frequently refractory to pharmacological therapies and endocardial and epicardial catheter ablation. Eleven patients with an age from 31 to 79 (median 56) years old, underwent map-guided surgery for left ventricular summit VT. All patients had undergone 1-5 unsuccessful sessions of catheter ablation for incessant VT, preoperatively. Five patients had suffered VT storm and 1 had a history of cardiopulmonary resuscitation. Four patients had implanted with a defibrillator. Epicardium to endocardium transmural cryothermia was applied at the VT origin determined by intraoperative epicardial mapping with electro-anatomical mapping system. Harmonic scalpel was used to remove the epicardial fat and cryothermia was applied directly to the myocardium, avoiding thermal or mechanical injuries to the coronary vessels. Additional endocardial cryothermia at the VT origin was performed by a cryoprobe introduced into the left ventricular cavity through an aortotomy. There was no surgical mortality or long-term mortality related to VT during a median follow-up period of 60 months (interquartile range: 34-82). Five-year freedom from preoperatively documented left ventricular summit VT and non-documented VT was 91% and 73%, respectively. All the patients with postoperative VT underwent successful catheter ablation. Other patients were free from VT during the follow-up period. Epicardial to endocardial transmural cryothermia at the VT origin guided by intraoperative electro-anatomical mapping with a close collaboration with electrophysiologists was crucial in successful surgery for left ventricular summit VT.

Unipolar and bipolar electrograms to predict successful ablation site of premature ventricular contractions originating from the free wall of the tricuspid annulus.

This study aimed to identify the characteristics of unipolar and bipolar electrogram (UniEGM and BiEGM) in guiding successful ablation of premature ventricular contractions (PVCs) originating from the free wall of the ventricular aspect of the tricuspid annulus (TA). We hypothesized that the negative concordance pattern (NCP) on the onset of UniEGM and BiEGM, together with the least value of the difference between the earliest BiEGM and UniEGM dV/dTmax, might improve the accuracy of conventional mapping. Thirty consecutive patients who underwent successful catheter ablation from February 2018 to July 2021 were retrospectively analyzed. The BiEGM and UniEGM for successful ablation sites were compared with those for non-successful ablation sites. Among the 30 patients, 30 successful and 26 nonsuccessful ablation sites were compared. The earliest activation time of the BiEGM (BiEGMoneset-QRS) was 25 ± 6 ms for the successful ablation sites and 21 ± 6 ms for the nonsuccessful ablation sites (p = .47). The value of the difference in the earliest BiEGM and UniEGM dV/dTmax differed between successful and nonsuccessful ablation sites (6.4 ± 3.6 ms vs. 10.4 ± 6.8 ms). NCP was observed at 90.0% and 42.3% of the successful and nonsuccessful ablation sites, respectively. Alignment of NCP and BiEGMonset-UniEGM ≤6 ms was applied as the mapping criterion for successful PVC suppression (73.1% sensitivity and 87.7% specificity). The area under the receiver-operating characteristic curve for this cutoff was 0.85. Mapping based on an NCP at the onset of the BiEGM and UniEGM and the least difference value of the earliest BiEGM and UniEGM dV/dTmax had an excellent predictive value for successful ablation. These strategies may reduce the number of radiofrequency catheter ablation (RFCA) applications for free-wall tricuspid annular PVCs.

Predictors of Successful Radiofrequency Catheter Ablation of Premature Ventricular Complexes

Abstract Introduction Patients with a high premature ventricular complexes PVC burden can benefit from catheter ablation, which is an effective and curative strategy for improving symptoms while simultaneously reducing PVC burden. Depending on the origin of the PVC, catheter ablation can be used as first-line therapy or as a last resort in cases of more rare origins when medication fails or is not tolerated/wanted. Aim The aim of this study is to determine the predictors of successful Radiofrequency catheter ablation of premature ventricular complexes. Participants &Methods A total of 100 patients with PVCs burden greater than 15% who were scheduled for conventional or 3D ablation at electrophysiology unit of Ain Shams University between 2018 and 2020 were included in the study. Success was defined as acute elimination of PVCs in Cath-lab with a 30 minutes waiting period and PVCs burden <3% on follow up Holter recording. Results The success rate was 83% among 100 patients (mean age 41.31 ± 17.69 years, 52% female patients), with 68% of the patients undergoing conventional ablations. Success was predicted by age (<58 years), outflow tract (OT) origin of PVCs, and the existence of a pre-QRS signal on the ablation catheter> 33 msec (Pvalue < 0.001).There was no statistical difference between conventional ablation and 3D ablation in this study regarding predictors of success. Conclusion Age, Origin of PVCs and pre-QRS signal are predictors of success of PVCs ablation. Abbreviations ECG: electrocardiogram; LVEF: left ventricular ejection fraction; LVOT: left ventricular outflow tract; PVC: premature ventricular contraction; RFCA: radiofrequency catheter ablation; RV: right ventricular/ventricle; RVOT: right ventricular outflow tract; OT: Outflow tract

Complicated catheter ablation of premature ventricular contractions from the left sinus of Valsalva in a young female. Case presentation.

Idiopathic premature ventricular complexes (PVCs) are usually benign and are often treated conservatively. Data regarding radiofrequency catheter ablation (RFA) of PVCs from the aortic sinus of Valsalva are spare. Furthermore, there are limited data regarding complications and their solutions during RFA of PVCs from the aortic sinus of Valsalva. Here we describe a clinical case of symptomatic PVCs in a 27yrold young woman with reduced exercise tolerance and dyspnea. The patient had taken anti-arrhythmic group Ic, II, and III drugs with no significant effect. Successful catheter ablation of PVCs from the left sinus of Valsalva was complicated by acute occlusion of the left main coronary artery (LCA) followed by polymorphic ventricular tachycardia and ventricular fibrillation. Cardioversion and intravenous antiarrhythmic administration restored the sinus rhythm. The LCA was stented with a bioresorbable Magmaris stent with the support of extracorporeal membrane oxygenation that was required due to severe hypotension and ineffectiveness of vasopressors. After the procedure, a favorable angiographic effect was noted. The result of stenting was monitored with IVUS intravascular navigation. The patient was discharged in a satisfactory condition on the 10th day after the procedure. Special attention should be applied to prevent complications and to careful patient selection for RFA in the left sinus of Valsalva, and care must be taken to avoid injury to the LCA. Timely and correct procedures can result in patient survival even after acute LCA injury and occlusion.

How different very late recurrence of atrial fibrillation 5 years after catheter ablation?

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Ministry of Health and Welfare the Basic Science Research Program run by the National Research Foundation of Korea (NRF). Background Atrial fibrillation (AF) is a chronic progressive disease that recurs continuously even after successful AF catheter ablation (AFCA). Objective We explored the mechanism of this long-term recurrence by comparing the patient characteristics and redo-ablation findings. Methods Among 4,248 patients who underwent a de novo AFCA and protocol-based rhythm follow-up at single centers, we enrolled 1,417 patients (71.7% male, age 60.0 [52.0–67.0] years, 57.9% paroxysmal AF) who experienced clinical recurrences (CRs) of the disease, and divided them according to the period of recurrence: within one year (n=645), 1–2 years (n=339), 2–5 years (n=308), and after 5-years (CR>5yr, n=125). We also compared the redo-mapping and ablation outcomes in 198 patients. Results In patients with a CR>5yr, the proportion of paroxysmal AF was higher (p=0.031); however, the left atrial (LA) volume (computed tomography, p=0.003), LA voltage (p=0.003), frequency of early recurrence (p<0.001), and use of post-procedure anti-arrhythmic drugs (p<0.001) were lower. A CR>5yr was independently associated with the low LA volume (odds ratio [OR] 0.99 [0.99–1.00], p=0.019), low LA voltage (OR 0.62 [0.41–0.95], p=0.030), and lower early recurrence (OR 0.39 [0.23–0.64], p<0.001). Extra-pulmonary vein (PV) triggers (P for trend 0.003) during repeat procedures were significantly greater in patients with a CR>5yr, despite no difference in the de novo protocol. The rhythm outcome of repeat ablation procedures did not differ with the timing of the CR (log-rank p=0.330). Conclusions Patients with a later CR showed a smaller LA volume, lower LA voltage, and higher extra-PV triggers during the repeat procedure, suggesting progression of AF.

The V1 transition ratio: electrocardiographic criterion for predicting the success of ablation for outflow tract premature ventricular contractions

Abstract Funding Acknowledgements Type of funding sources: None. Background Several electrocardiographic (ECG) criteria have been proposed for distinguishing left from right ventricular outflow tract premature ventricular contractions (OTPVCs) origins. However, electrocardiographic criteria predicting successful catheter ablation (CA) for OTPVCs are still unknown regardless of right and left ventricular origins. Methods We enrolled 63 patients who underwent CA for OTPVCs from September 2020 to August 2022, except patients with bundle branch block and axis deviation in 12-lead ECG. Radiofrequency catheter ablation (RFCA) was performed using 3D-mapping system and irrigation catheter. Electrocardiographic parameters of successful and unsuccessful patients were retrospectively analyzed. The transition ratios were calculated by the percentage R-wave during PVC (R/R+S) PVC divided by the percentage R-wave in sinus rhythm (R/R+S) SR . Success of CA for OTPVCs was defined as absence of targeted PVCs during all follow up visits and PVC burden <5% on follow-up period. Results 54 patients (85.7%) were success and 9 patients (14.3%) were unsuccess. Age, sex, Ejection Fraction (EF) and the burden of PVCs before CA were similar between 2 group. (Age: 50±15 vs 54±12 years, p=0.51, male: 46.3 vs 53.7%, p=0.73, EF: 66(58-73) vs 69(59-74), p=0.52, burden of PVCs: 22(17-29) vs 15(13-33)%, p=0.45). V1 transition ratio of unsuccessful group was significantly higher than successful group. (0.70(0.32-1.49) vs 1.55(1.09-9.37), p=0.013) V2 and V3 transition ratios were not significantly different between the two groups. The best cutoff values of V1 transition ratio were 1.0 (AUC 0.78, 95%CI: 0.61-0.94, sensitivity 0.70, specificity 0.88). Conclusion V1 transition ratio>1.0 is more likely to be associated with a higher rate of RFCA failure of OTPVCs.

Predictors of arrhythmia during pregnancy in adults with congenital heart disease

BackgroundRisk prediction of arrhythmia during pregnancy in adult congenital heart disease (ACHD) patients is currently lacking, and the impact of preconception catheter ablation on future antepartum arrhythmia has not been studied. MethodsWe conducted a single-center, retrospective cohort study of pregnancies in ACHD patients. Clinically significant arrhythmia events during pregnancy were described, predictors of arrhythmia were analyzed, and a risk score devised. The impact of preconception catheter ablation on antepartum arrhythmia was assessed. ResultsThe study included 172 pregnancies in 137 patients. Arrhythmia events occurred in 25 (15%) of pregnancies, with 64% of events occurring in the second trimester and sustained supraventricular tachycardia being the most common rhythm. Univariate predictors of arrhythmia were history of tachyarrhythmia (OR 20.33, 95% CI 6.95–59.47, p < 0.001, Fontan circulation (OR 11.90, 95% CI 2.60–53.70, p < 0.001), baseline physiologic class C/D (OR 3.72, 95% CI 1.54–9.01, p = 0.002) and history of multiple valve interventions (OR 3.10, 95% CI 1.20–8.20, p = 0.017). Three risk factors (excluding multiple valve interventions) were used to formulate a risk score, with a cutoff of ≥2 points predicting antepartum arrhythmia with sensitivity and specificity of 84%. While recurrence of the index arrhythmia was not observed following successful catheter ablation, preconception ablation did not impact odds of antepartum arrhythmia. ConclusionsWe provide a novel risk stratification scheme for predicting antepartum arrhythmia in ACHD patients. The role of contemporary preconception catheter ablation in risk reduction needs further refinement with multicenter investigation.