Incidental ablation of ganglionated plexus during atrial fibrillation ablation.

BACKGROUND: Cardioneuroablation targeting the autonomic nerves within ganglionated plexus (GP) has been used to treat atrial fibrillation (AF). Incidental cardioneuroablation may be an important mechanism by which pulmonary vein isolation (PVI) is effective. Automated fractionation mapping software can identify regions of fractionation correlating with GP locations. OBJECTIVE: To examine the overlap between standard PVI ablation lesions and fractionated electrograms suggestive of GP. METHODS: We retrospectively examined AF ablations performed from 2021 to 2023 that included only PVI performed using wide antral circumferential isolation without prospective evaluation of fractionation. Retrospectively, a fractionation map was created (width 10 ms, refractory time 30 ms, roving sensitivity 0.1 mv, and threshold of 2). We evaluated the anatomic overlap between PVI lesions and fractionation in regions associated with GP. RESULTS: Among 52 patients (mean 65 (IQR 46-74) years, 82% male, and 69% paroxysmal AF), sites of fractionation corresponding to GP locations were seen in all cases. PVI ablation incidentally overlapped with fractionation in 50 (96%) patients. On average, 26% of the fractionation corresponding with GP locations were incidentally ablated. The highest proportion of fractionated areas were ablated in the left superior (36%) and right superior (31%) GP regions. More complete incidental ablation of these regions was associated with a greater intraprocedural increase in heart rate (ρ = 0.46, p < 0.001), which was subsequently associated with freedom from AF during 15.9 ± 5.2 months of follow-up. CONCLUSION: Patients undergoing AF ablation universally have fractionated electrograms corresponding to anticipated sites of GP. Partial ablation of these regions frequently occurs incidentally during PVI.

Noninvasive Visualization of the Atrioventricular Conduction System Using Cardiac Computed Tomography.

Importance: Noninvasive localization of the compact atrioventricular node and the proximal specialized conduction system (AVCS) would enhance planning for transcatheter aortic valve and complex or congenital heart disease surgical procedures. Objective: To test the hypothesis that preprocedure contrast-enhanced cardiac computed tomography (CECT) can accurately localize the AVCS by identification of the fat that insulates the conductive myocardium. Design, Setting, and Participants: This was a prospective cohort study that took place at an academic tertiary care center. Included in the study were patients with CECT acquired less than 1 month before atrial fibrillation ablation and electroanatomic localization of the His electrogram signal on electroanatomic mapping (EAM) between January 2022 and January 2023. Exposures: Preprocedure CECT. Main Outcomes and Measures: The distance from the His electrogram signal to the fat segmentation encompassing the AVCS on CECT, after registration of the images to EAM. Results: Among 20 patients (mean [SD] age, 66 [10] years; 15 male [75%]) in the cohort, the mean (SD) attenuation of the AVCS fat segmentation was 2.9 (21.5) Hounsfield units. The mean (SD) distance from the His electrogram to the closest AVCS fat voxel was 3.3 (1.6) mm. Conclusions and Relevance: Results of this cohort study suggest that CECT could accurately localize the fatty tissue that insulates the AVCS from surrounding atrial and ventricular myocardium and may enhance the efficacy and safety of procedures targeting the conduction system and structures in its proximity.

The Ablate-by-LAWT multicentre prospective study: Personalized paroxysmal atrial fibrillation ablation with ablation index adapted to local left atrial wall thickness.

BACKGROUND: Personalized radiofrequency (RF) ablation for paroxysmal atrial fibrillation (PAF), adapting the ablation index (AI) to local left atrial wall thickness (LAWT), proved to be highly efficient maintaining high arrhythmia-free survival rates. However, multicentre data are lacking. This multicentre, prospective, non-randomized study was conducted at 5 tertiary hospitals and sought to assess the safety, efficacy, and reproducibility of the LAWT-guided ablation for PAF. METHODS: Consecutive patients referred for first-time PAF were prospectively enrolled. The LAWT maps were obtained from preprocedural multidetector computed tomography and integrated into the navigation system. AI was titrated according to the local LAWT, and the ablation line was personalized to avoid the thickest regions while encircling the pulmonary veins (PVs). RESULTS: A total 109 patients (60.1 ± 9.4 years, 64.2% male) were enrolled. Median procedure time was 61.7 min (48.4-83.8), fluoroscopy time was 1.0 min (0.4-3.3), and RF time was 13.9 min (12.3-16.8). Median AI tailored to the local LAWT was 393 (374-412) for the anterior wall and 340 (315-378) for the posterior wall. Right and left PVs first-pass isolation was achieved in 89% and 91.7% of the patients, respectively. At 12-month follow-up, freedom from any atrial arrhythmia was 93.4% (95% CI 88.7-98.1), without differences across centres (P = 0.169). One patient experienced femoral artery pseudoaneurysm, with no other serious procedural-related complication. CONCLUSION: The Ablate-by-LAWT study proved that LAWT-guided PV isolation for PAF is safe, effective, and efficient in a multicentre setting. Twelve-month recurrence-free survival exceeded 90% (NCT04218604).

Incremental Benefit of Stepwise Nonpulmonary Vein Trigger Provocation During Catheter Ablation of Atrial Fibrillation.

BACKGROUND: The importance of nonpulmonary vein (PV) triggers for the initiation/recurrence of atrial fibrillation (AF) is well established. OBJECTIVES: This study sought to assess the incremental benefit of provocative maneuvers for identifying non-PV triggers. METHODS: We included consecutive patients undergoing first-time AF ablation between 2020 and 2022. The provocation protocol included step 1, identification of spontaneous non-PV triggers after cardioversion of AF and/or during sinus rhythm; step 2, isoproterenol infusion (3, 6, 12, and 20-30 µg/min); and step 3, atrial burst pacing to induce AF followed by cardioversion during residual or low-dose isoproterenol infusion or induce focal atrial tachycardia. Non-PV triggers were defined as non-PV ectopic beats triggering AF or sustained focal atrial tachycardia. RESULTS: Of 1,372 patients included, 883 (64.4%) underwent the complete stepwise provocation protocol with isoproterenol infusion and burst pacing, 334 (24.3%) isoproterenol infusion only, 77 (5.6%) burst pacing only, and 78 (5.7%) no provocative maneuvers (only step 1). Overall, 161 non-PV triggers were found in 135 (9.8%) patients. Of these, 51 (31.7%) non-PV triggers occurred spontaneously, and the remaining 110 (68.3%) required provocative maneuvers for induction. Among those receiving the complete stepwise provocation protocol, there was a 2.2-fold increase in the number of patients with non-PV triggers after isoproterenol infusion, and the addition of burst pacing after isoproterenol infusion led to a total increase of 3.6-fold with the complete stepwise provocation protocol. CONCLUSIONS: The majority of non-PV triggers require provocative maneuvers for induction. A stepwise provocation protocol consisting of isoproterenol infusion followed by burst pacing identifies a 3.6-fold higher number of patients with non-PV triggers.

Utility of noninvasive electrocardiographic imaging in the localization of nonpulmonary vein triggers of atrial fibrillation determined by pacing common trigger sites.

INTRODUCTION: Identifying the origin of nonpulmonary vein atrial fibrillation (AF) triggers (NPVTs) after pulmonary vein isolation (PVI) can be challenging. We aimed to determine if noninvasive electrocardiographic imaging (ECGi) could localize pacing from common NPVT sites. ECGi combines measured body surface potentials with heart-torso geometry acquired from computed tomography (CT) to generate an activation map. METHODS: In 12 patients with AF undergoing first time ablation, the ECGi vest was fitted for preprocedural CT scan and worn during the procedure. After PVI, we performed steady-state pacing from 15 typical anatomic NPVT sites at a cycle length of 700-800 ms. We co-registered the invasive anatomic map with the CT-based ECGi epicardial activation map to compare ECGi predicted to true pacing origin. RESULTS: In the study cohort (67% male, 58% persistent AF, and 67% with left atrial dilation), 148 (82%) pacing sites had both capture and adequate anatomy acquired from the three-dimensional mapping system to co-register with ECGi activation map. Median distance between true pacing sites and point of earliest epicardial activation derived from the ECGi maps for all sites was 17 mm (interquartile range, 10-22 mm). Assuming paced sites treated as regions with a radius of 2.5 cm, the earliest activation site on ECGi map falls within the region with 94% accuracy. CONCLUSION: ECGi can approximate the origin of paced beats from common NPVT sites to within a median distance of 17 mm. A rapidly identified region may then be the focus of more detailed catheter-based mapping techniques to facilitate successful localization and ablation of NPVTs.

ACR Appropriateness Criteria® Preprocedural Planning for Left Atrial Procedures in Atrial Fibrillation.

This document summarizes the relevant literature for the selection of preprocedural imaging in three clinical scenarios in patients needing endovascular treatment or cardioversion of atrial fibrillation. These clinical scenarios include preprocedural imaging prior to radiofrequency ablation; prior to left atrial appendage occlusion; and prior to cardioversion. The appropriateness of imaging modalities as they apply to each clinical scenario is rated as usually appropriate, may be appropriate, and usually not appropriate to assist the selection of the most appropriate imaging modality in the corresponding clinical scenarios. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

The Safety and Efficacy of Epicardial Carbon Dioxide Insufflation Compared With Conventional Epicardial Access.

BACKGROUND: Epicardial (Epi) access is commonly required during ventricular tachycardia ablation. Conventional Epi (ConvEpi) access targets a "dry" pericardial space presenting technical challenges and risk of complications. Recently, intentional puncture of coronary venous branches with Epi carbon dioxide insufflation (EpiCO2) has been described as a technique to improve Epi access. The safety of this technique relative to conventional methods remains unproven. OBJECTIVES: The authors sought to compare the feasibility and safety of EpiCO2 to ConvEpi access. METHODS: All patients at a high-volume center undergoing Epi access between January 2021 and December 2023 were included and grouped according to ConvEpi or EpiCO2 approach. Access technique was according to the discretion of the operator. RESULTS: Epi access was attempted in 153 cases by 17 different operators (80 ConvEpi vs 73 EpiCO2). There was no difference in success rate whether the ConvEpi or EpiCO2 approach was used (76 [95%] cases vs 67 [91.8%] cases; P = 0.4). Total Epi access time was shorter in the ConvEpi group compared with the EpiCO2 group (16.3 ± 11.6 minutes vs 26.9 ± 12.7 minutes; P < 0.001), though the total procedure duration was similar. Major Epi access-related complications occurred in only the ConvEpi group (6 [7.5%] ConvEpi vs 0 [0%] EpiCo2; P = 0.02). Bleeding ≥80 mL was more frequently observed following ConvEpi access (14 [17.5%] cases vs 4 [5.5%] cases; P = 0.02). After adjusting for age, repeat Epi access, and antithrombotic therapy, EpiCO2 was associated with a reduction in bleeding ≥80 mL (OR: 0.27; 95% CI: 0.08-0.89; P = 0.03). CONCLUSIONS: EpiCO2 access is associated with lower rates of major complication and bleeding when compared with ConvEpi access.

Long-Term Freedom From Ventricular Arrhythmias in ARVC With Endocardial Only Ablation: Predictors of Success.

BACKGROUND: Although the epicardial predominance of substrate abnormalities has been well demonstrated in early stages of arrhythmogenic right ventricular cardiomyopathy (ARVC), endocardial (ENDO) ablation may suffice to eliminate ventricular tachycardia (VT) in some patients. OBJECTIVES: This study aimed to report the long-term outcomes of ENDO-only ablation in ARVC patients and factors that predict VT-free survival. METHODS: We included consecutive patients with Task Force Criteria diagnosis of ARVC undergoing a first ENDO-only VT ablation between 1998 and 2020. Ablation was predominantly guided by activation/entrainment mapping for mappable VTs and pace mapping/targeting abnormal electrograms for unmappable VTs. The primary endpoint was freedom from any recurrent sustained VT after the last ENDO-only ablation. RESULTS: Seventy-four ARVC patients underwent ENDO-only VT ablation. VT noninducibility was achieved in 49 (66%) patients. During median follow-up of 6.6 years (Q1-Q3: 3.4-11.2 years), 40 (54.1%) patients remained free from any VT recurrence with rare VT ≤2 episodes in additional 12.2%. Among patients with noninducibility, VT-free survival was 75.5% during long-term follow-up. In multivariable analysis, >45 y of age at diagnosis (HR: 0.41; 95% CI: 0.17-0.98) and VT noninducibility (HR: 0.36; 95% CI: 0.16-0.80) were predictors of VT-free survival. CONCLUSIONS: Long-term VT-free survival can be achieved in over half of ARVC patients following ENDO-only VT ablation, increasing to over 75% if VT noninducibility is achieved. Our results support consideration of a stepwise ENDO-only approach before proceeding to epicardial ablation if VT noninducibility can be achieved particularly in older patients.

Lipomatous Metaplasia Is Associated With Ventricular Tachycardia Recurrence Following Ablation in Patients With Nonischemic Cardiomyopathy.

BACKGROUND: Ventricular tachycardia (VT) recurrence rates remain high following ablation among patients with nonischemic cardiomyopathy (NICM). OBJECTIVES: This study sought to define the prevalence of lipomatous metaplasia (LM) in patients with NICM and VT and its association with postablation VT recurrence. METHODS: From patients who had ablation of left ventricular VT, we retrospectively identified 113 consecutive NICM patients with preprocedural contrast-enhanced cardiac computed tomography (CECT), from which LM was segmented. Nested within this cohort were 62 patients that prospectively underwent CECT and cardiac magnetic resonance from which myocardial border zone and dense late gadolinium enhancement (LGE) were segmented. A control arm of 30 NICM patients without VT with CECT was identified. RESULTS: LM was identified among 57% of control patients without VT vs 83% of patients without VT recurrence and 100% of patients with VT recurrence following ablation. In multivariable analyses, LM extent was the only independent predictor of VT recurrence, with an adjusted HR per 1-g LM increase of 1.1 (P < 0.001). Patients with LM extent ≥2.5 g had 4.9-fold higher hazard of VT recurrence than those with LM <2.5 g (P < 0.001). In the nested cohort with 32 VT recurrences, LM extent was independently associated with VT recurrence after adjustment for border zone and LGE extent (HR per 1 g increase: 1.1; P = 0.036). CONCLUSIONS: Myocardial LM is prevalent in patients with NICM of a variety of etiologies, and its extent is associated with postablation VT recurrence independent of the degree of fibrosis.

Understanding the Utility of Endocardial Electrocardiographic Imaging in Epi-Endocardial Mapping of 3D Reentrant Circuits.

Background: Studies of VT mechanisms are largely based on a 2D portrait of reentrant circuits on one surface of the heart. This oversimplifies the 3D circuit that involves the depth of the myocardium. Simultaneous epicardial and endocardial (epi-endo) mapping was shown to facilitate a 3D delineation of VT circuits, which is however difficult via invasive mapping. Objective: This study investigates the capability of noninvasive epicardial-endocardial electrocardiographic imaging (ECGI) to elucidate the 3D construct of VT circuits, emphasizing the differentiation of epicardial, endocardial, and intramural circuits and to determine the proximity of mid-wall exits to the epicardial or endocardial surfaces. Methods: 120-lead ECGs of VT in combination with subject-specific heart-torso geometry are used to compute unipolar electrograms (CEGM) on ventricular epicardium and endocardia. Activation isochrones are constructed, and the percentage of activation within VT cycle length is calculated on each surface. This classifies VT circuits into 2D (surface only), uniform transmural, nonuniform transmural, and mid-myocardial (focal on surfaces). Furthermore, the endocardial breakthrough time was accurately measured using Laplacian eigenmaps, and by correlating the delay time of the epi-endo breakthroughs, the relative distance of a mid-wall exit to the epicardium or the endocardium surfaces was identified. Results: We analyzed 23 simulated and in-vivo VT circuits on post-infarction porcine hearts. In simulated circuits, ECGI classified 21% as 2D and 78% as 3D: 82.6% of these were correctly classified. The relative timing between epicardial and endocardial breakthroughs was correctly captured across all cases. In in-vivo circuits, ECGI classified 25% as 2D and 75% as 3D: in all cases, circuit exits and entrances were consistent with potential critical isthmus delineated from combined LGE-MRI and catheter mapping data. Conclusions: ECGI epi-endo mapping has the potential for fast delineation of 3D VT circuits, which may augment detailed catheter mapping for VT ablation.

Class 1C Antiarrhythmics for Premature Ventricular Complex Suppression in Nonischemic Cardiomyopathy With Implantable Cardioverter-Defibrillators.

BACKGROUND: Premature ventricular complexes (PVCs) are common and associated with worse outcomes in patients with heart failure. Class 1C antiarrhythmic drugs (AADs) effectively suppress PVCs, but guidelines currently restrict their use in structural heart disease. OBJECTIVES: This study aimed to assess the safety and efficacy of class 1C AADs in patients with nonischemic cardiomyopathy (NICM) and implantable cardioverter-defibrillators (ICDs). METHODS: All patients with NICM and an ICD treated with flecainide or propafenone at the Hospital of the University of Pennsylvania between 2014 and 2022 were identified. PVC burden, left ventricular ejection fraction (LVEF), and biventricular pacing percentage were compared before and during class 1C AAD treatment. Safety outcomes included sustained atrial and ventricular arrhythmias, heart failure admissions, and death. RESULTS: We identified 34 patients, 23 receiving flecainide and 11 propafenone. Most patients (62%) had failed other AADs or catheter ablation (68%) prior to class 1C AAD initiation. PVC burden decreased from 20% ± 13% to 6% ± 7% (P < 0.001), LVEF increased from 33% ± 9% to 37% ± 10% (P = 0.01), and biventricular pacing percentage increased from 85% ± 9% to 93% ± 7% (P = 0.01). Sustained ventricular tachycardia (2 vs 9 patients) and admissions for decompensated heart failure (2 vs 3 patients) decreased compared with the 12 months prior to class 1C AAD initiation. CONCLUSIONS: Class 1C AADs effectively suppressed PVCs in patients with NICM and ICDs, leading to increases in LVEF and biventricular pacing percentage. In this limited sample, their use was safe. Larger studies are needed to confirm the safety of this approach.

Risk scores for prediction of paroxysmal atrial fibrillation after acute ischemic stroke or transient ischemic attack: A systematic review and meta-analysis.

Introduction: Detection of paroxysmal atrial fibrillation (PAF) is crucial for secondary prevention in patients with recent strokes of unknown etiology. This systematic review and meta-analysis assess the predictive power of available risk scores for detecting new PAF after acute ischemic stroke (AIS). Methods: PubMed, Embase, Scopus, and Web of Science databases were searched until September 2023 to identify relevant studies. A bivariate random effects meta-analysis model pooled data on sensitivity, specificity, and area under the curve (AUC) for each score. The QUADAS-2 tool was used for the quality assessment. Results: Eventually, 21 studies with 18 original risk scores were identified. Age, left atrial enlargement, and NIHSS score were the most common predictive factors, respectively. Seven risk scores were meta-analyzed, with iPAB showing the highest pooled sensitivity and AUC (sensitivity: 89.4%, specificity: 74.2%, AUC: 0.83), and HAVOC having the highest pooled specificity (sensitivity: 46.3%, specificity: 82.0%, AUC: 0.82). Altogether, seven risk scores displayed good discriminatory power (AUC ≥0.80) with four of them (HAVOC, iPAB, Fujii, and MVP scores) being externally validated. Conclusion: Available risk scores demonstrate moderate to good predictive accuracy and can help identify patients who would benefit from extended cardiac monitoring after AIS. External validation is essential before widespread clinical adoption.

Evaluation of organized atrial arrhythmias after cryptogenic stroke.

Background: Long-term rhythm monitoring to detect atrial fibrillation (AF) following a cryptogenic stroke (CS) is well established. However, the burden of organized atrial arrhythmias in this population is not well defined. Objective: The purpose of this study was to assess the incidence and risk factors for organized atrial arrhythmias in patients with CS. Methods: We evaluated all patients with CS who received an insertable cardiac monitor (ICM) between October 2014 and April 2020. All ICM transmissions categorized as AF, tachycardia, or bradycardia were reviewed. We evaluated the time to detection of organized AF and the combination of either organized atrial arrhythmia or AF. Results: A total of 195 CS patients with ICMs were included (51% men; mean age 66 ± 12 years; mean CHA2DS2-VASC score 4.6). Over mean follow-up of 18.9 ± 11.2 months, organized atrial arrhythmias lasting ≥30 seconds were detected in 45 patients (23%), of whom 62% did not have AF. Seventeen patients had both organized atrial arrhythmia and AF, and another 21 patients had AF only. Compared to those with normal left atrial size, patients with left atrial enlargement had a higher adjusted risk for development of atrial arrhythmias (mild left atrial enlargement: hazard ratio 1.99; 95% confidence interval 1.06-3.75; moderate/severe left atrial enlargement: hazard ratio 3.06; 95% confidence interval 1.58-5.92). Conclusion: Organized atrial arrhythmias lasting ≥30 seconds are detected in nearly one-fourth of CS patients. Two-thirds of these patients did not have AF. Further studies are required to evaluate the impact of organized atrial arrhythmias on recurrent stroke risk.

Sarcoid heart disease and imaging.

Cardiac sarcoidosis (CS) can mimic any cardiomyopathy due to its ability to manifest with a variety of clinical presentations. The exact prevalence of CS remains unknown but has been reported ranging from 2.3% to as high as 29.9% among patients presenting with new onset cardiomyopathy and/or atrioventricular block. Early and accurate diagnosis of CS is often challenging due to the nature of disease progression and lack of diagnostic reference standard. The current diagnostic criteria for CS are lacking in sensitivity and specificity. Here, we review the contemporary role of advanced imaging modalities such as cardiac magnetic resonance imaging and positron emission tomography/computed tomography imaging in diagnosing and prognosticating patients with CS.

SCMR expert consensus statement for cardiovascular magnetic resonance of patients with a cardiac implantable electronic device.

Cardiovascular magnetic resonance (CMR) is a proven imaging modality for informing diagnosis and prognosis, guiding therapeutic decisions, and risk stratifying surgical intervention. Patients with a cardiac implantable electronic device (CIED) would be expected to derive particular benefit from CMR given high prevalence of cardiomyopathy and arrhythmia. While several guidelines have been published over the last 16 years, it is important to recognize that both the CIED and CMR technologies, as well as our knowledge in MR safety, have evolved rapidly during that period. Given increasing utilization of CIED over the past decades, there is an unmet need to establish a consensus statement that integrates latest evidence concerning MR safety and CIED and CMR technologies. While experienced centers currently perform CMR in CIED patients, broad availability of CMR in this population is lacking, partially due to limited availability of resources for programming devices and appropriate monitoring, but also related to knowledge gaps regarding the risk-benefit ratio of CMR in this growing population. To address the knowledge gaps, this SCMR Expert Consensus Statement integrates consensus guidelines, primary data, and opinions from experts across disparate fields towards the shared goal of informing evidenced-based decision-making regarding the risk-benefit ratio of CMR for patients with CIEDs.

Predictors of nonpulmonary vein triggers for atrial fibrillation: A clinical risk score.

BACKGROUND: Targeting non-pulmonary vein triggers (NPVTs) after pulmonary vein isolation may reduce atrial fibrillation (AF) recurrence. Isoproterenol infusion and cardioversion of spontaneous or induced AF can provoke NPVTs but typically require vasopressor support and increased procedural time. OBJECTIVE: The purpose of this study was to identify risk factors for the presence of NPVTs and create a risk score to identify higher-risk subgroups. METHODS: Using the AF ablation registry at the Hospital of the University of Pennsylvania, we included consecutive patients who underwent AF ablation between January 2021 and December 2022. We excluded patients who did not receive NPVT provocation testing after failing to demonstrate spontaneous NPVTs. NPVTs were defined as non-pulmonary vein ectopic beats triggering AF or focal atrial tachycardia. We used risk factors associated with NPVTs with P <.1 in multivariable logistic regression model to create a risk score in a randomly split derivation set (80%) and tested its predictive accuracy in the validation set (20%). RESULTS: In 1530 AF ablations included, NPVTs were observed in 235 (15.4%). In the derivation set, female sex (odds ratio [OR] 1.40; 95% confidence interval [CI] 0.96-2.03; P = .080), sinus node dysfunction (OR 1.67; 95% CI 0.98-2.87; P = .060), previous AF ablation (OR 2.50; 95% CI 1.70-3.65; P <.001), and left atrial scar (OR 2.90; 95% CI 1.94-4.36; P <.001) were risk factors associated with NPVTs. The risk score created from these risk factors (PRE2SSS2 score; [PRE]vious ablation: 2 points, female [S]ex: 1 point, [S]inus node dysfunction: 1 point, left atrial [S]car: 2 points) had good predictive accuracy in the validation cohort (area under the receiver operating characteristic curve 0.728; 95% CI 0.648-0.807). CONCLUSION: A risk score incorporating predictors for NPVTs may allow provocation of triggers to be performed in patients with greatest expected yield.