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Premature ventricular contractions (PVCs) are a common form of arrhythmic events, often representing an idiopathic and benign condition without further therapeutic interventions. However, in certain circumstances PVCs may represent the epiphenomenon of a concealed structural heart disease (SHD). Surface 12‑leads EKG and 24-h dynamic EKG are necessary to assess their main characteristics such as site of origin, frequency and complexity. Echocardiography represents the first-line imaging tool recommended to evaluate cardiac structures and function. Cardiac Magnetic Resonance (CMR) is recognized as a superior modality for detecting structural cardiac alterations, that might evade detection by conventional echocardiography. Moreover, in specific populations such as athletes, CMR may have a crucial role to exclude a concealed SHD and the risk of serious arrhythmic events during sport activity. Some clinical characteristics such as male sex, older age or family history of sudden cardiac death (SCD) or cardiomyopathy, and some electrocardiographic features of PVCs, in particular a right branch bundle block (RBBB) with superior/intermediate axis morphology, the reproducibility of VAs during exercise test (ET) or the evidence of complex ventricular arrhythmias, may warrant a CMR evaluation, due to the high probability of SHD. In this systematic review our objective was to provide an exhaustive overview on the role of CMR in detecting a concealed SHD in patients with high daily burden of PVCs and a normal echocardiographic evaluation, paving the way for a more extensive utilization of CMR in presence of certain high-risk clinical and/or EKG features identified during the diagnostic workup., Competing Interests: Declaration of competing interest The authors have no relevant financial and non-financial interests to disclose., (Copyright © 2023. Published by Elsevier B.V.)

Background: The increasing use of intracardiac echocardiography (ICE) in the ablation of premature ventricular complexes (PVCs) has raised questions about its true efficacy and safety., Methods: This retrospective study collected the periprocedural complications and PVC burden post ablation. The risk factors of PVC recurrence was further explored., Results: The study included patients treated without ICE (control group, n = 451) and with ICE (ICE group, n = 155) from May 2019 to July 2022. The ICE group demonstrated significantly lower fluoroscopy times and X-ray doses. There were no major complications in the ICE group, and the difference in the occurrence of periprocedural complications between the groups was not statistically significant (p = 0.072). The long-term success rates were similar for the control and ICE groups (89.6% and 87.1%, respectively). The origin of PVCs was identified as the independent factor for ablation success., Conclusions: The use of ICE did not confer an advantage with regard to long-term success in PVCs ablation. To thoroughly evaluate the safety and effectiveness of ICE in PVCs ablation, a prospective, multicenter, randomized study is warranted., (© 2024. The Author(s).)

Background: Epicardial adipose tissue (EAT) is recognized as a clinical diagnostic marker for cardiometabolic disease. Thicker EAT may be associated with recurrence of ventricular tachycardia after ablation. The association between EAT volume and recurrence of premature ventricular complexes (PVC) following ablation has not been clarified. We investigated the association between EAT volume and PVC recurrence following radiofrequency catheter ablation., Methods and results: This retrospective study included 401 patients with PVC undergoing catheter ablation with preprocedural non-contrast computed tomography between 2017 and 2022. The impact of EAT volume in predicting PVC recurrence after ablation was analyzed. The mean (±SD) age of patients was 50.2±13.3 years. Multivariable Cox analysis revealed that a large EAT volume was an independent predictor of PVC recurrence after ablation during a median follow-up of 16.3 months. Kaplan-Meier analysis showed a difference in postablation PVC recurrence between the 2 groups dichotomized around the EAT volume cut-off. The risk of recurrence increased with increasing EAT volume according to restricted cubic spline regression. Furthermore, PVC originating from epicardial locations had larger EAT volumes than those originating from the right ventricular outflow tract., Conclusions: A large EAT volume was independently associated with PVC recurrence following ablation. Patients with PVC originating from epicardial sites had large EAT volumes. EAT volume may help stratify patients according to their risk of PVC recurrence after ablation.

Competing Interests: Conflict of interest: none declared.

Introduction and Objectives: We aimed to assess the effects of successful ablation on impaired left ventricular global longitudinal strain (LV-GLS) in patients with frequent premature ventricular contractions (PVCs). We also evaluated the potential risk factors of impaired LV-GLS., Methods: Thirty-six consecutive patients without any structural heart disease, who were treated with radiofrequency (RF) ablation due to frequent PVCs, were included in the study. All patients were evaluated with standard transthoracic and two-dimensional speckle tracking echocardiography., Results: Mean LV-GLS before ablation was 17.3±3.7 and 20.5±2.6 after ablation; the difference was statistically significant (p<0.01). Patients were categorized into two groups: those with LV-GLS value >-16% and those ≤16%. Low PVC E flow/post-PVC E flow and PVC SV/post-PVC SV ratios were associated with impaired LV-GLS., Conclusion: In symptomatic patients with frequent PVCs and normal left ventricular ejection fraction, we observed significant improvement in LV-GLS value following successful RF ablation. Patients with impaired LV-GLS more often display non-ejecting PVCs and post-extrasystolic potentiation (PEP) compared to patients with normal LV-GLS., (Copyright © 2023 Sociedade Portuguesa de Cardiologia. Publicado por Elsevier España, S.L.U. All rights reserved.)

Access to accurate and precise monitoring systems for cardiac arrhythmia could contribute significantly to preventing damage and subsequent heart disorders. The present research concentrates on using photoplethysmography (PPG) and arterial blood pressure (ABP) with deep convolutional neural networks (CNN) for the classification and detection of fetal cardiac arrhythmia or premature ventricular contractions (PMVCs). The framework for the study entails (Icentia 11k) a public dataset of ECG signals consisting of different cardiac abnormalities. Following this, the weights obtained from the Icentia 11k dataset are transferred to the proposed CNN. Finally, fine-tuning was carried out to improve the accuracy of classification. Results obtained showcase the capacity of the proposed method to detect and classify PMVCs into three types: Normal, P1, and P2 with an accuracy of 99.9%, 99.8%, and 99.5%., (© 2023. Australasian College of Physical Scientists and Engineers in Medicine.)

Background: Mitral annular disjunction (MAD) and the Pickelhaube sign are identified as risk factors for malignant ventricular arrhythmias (VAs) and sudden cardiac death in adults with mitral valve prolapse (MVP); their prevalence and consequences in children have never been studied., Objectives: To determine the proportion of MAD in children with MVP, and its potential link with VAs., Methods: A cohort of 49 consecutive children (mean age 12.8±3.0 years; 33 females) with MVP and comprehensive clinical arrhythmia (24-hour monitoring) and Doppler echocardiographic characterization, including pulsed-wave tissue Doppler (PWTD) of the lateral mitral annulus, was identified. The relationship between clinical and echocardiographic data and presence of VAs was studied., Results: MAD was common (n=25; 51%). Only five patients had significant VAs (Lown grade>2) characterized by polymorphic premature ventricular contractions or couplets. MAD was not associated with VAs on 24-hour Holter monitoring, but an association was found between VAs and spiked high-velocity midsystolic signal>16cm/s on PWTD (Pickelhaube sign) (P=0.004), myxomatous mitral valve (P=0.004) and left ventricular dilatation (P=0.01). T-wave inversion in inferolateral leads on electrocardiogram was more frequent in patients with versus without the Pickelhaube sign (P=0.03). No difference was found between patients with or without MAD regarding sex, history of palpitation, severity of mitral regurgitation, aortic root diameter and incidence of connective tissue disorders. Myocardial fibrosis was detected in two of three patients who underwent a complementary cardiac magnetic resonance examination., Conclusions: MAD is common in children with MVP; its presence was not associated with significant VAs on 24-hour Holter monitoring, but the Pickelhaube sign and presence of myxomatous mitral valve may help to detect patients prone to significant VAs. Myocardial fibrosis can be detected by cardiac magnetic resonance in children with significant VAs., (Copyright © 2023 Elsevier Masson SAS. All rights reserved.)

In Holter monitoring, the precise detection of standard heartbeats and ventricular premature contractions (PVCs) is paramount for accurate cardiac rhythm assessment. This study introduces a novel application of the 1D U-Net neural network architecture with the aim of enhancing PVC detection in Holter recordings. Training data comprised the Icentia 11k and INCART DB datasets, as well as our custom dataset. The model's efficacy was subsequently validated against traditional Holter analysis methodologies across multiple databases, including AHA DB, MIT 11 DB, and NST, as well as another custom dataset that was specifically compiled by the authors encompassing challenging real-world examples. The results underscore the 1D U-Net model's prowess in QRS complex detection, achieving near-perfect balanced accuracy scores across all databases. PVC detection exhibited variability, with balanced accuracy scores ranging from 0.909 to 0.986. Despite some databases, like the AHA DB, showcasing lower sensitivity metrics, their robust, balanced accuracy accentuates the model's equitable performance in discerning both false positives and false negatives. In conclusion, while the 1D U-Net architecture is a formidable tool for QRS detection, there's a clear avenue for further refinement in its PVC detection capability, given the inherent complexities and noise challenges in real-world PVC occurrences.

Background: Epicardial adipose tissue (EAT) is related to atrial fibrillation. The association between EAT volume and premature ventricular complexes (PVCs) remains unclear. Our study aimed to investigate the effect of EAT volume on the risk of frequent PVCs and burden levels of PVCs., Methods: This observational study retrospectively recruited consecutive patients who had consultation between 2019 and 2021 at the First Affiliated Hospital of Zhengzhou University. Frequent PVC patients ( n = 402) and control patients ( n = 402) undergoing non-contrast computed tomography (CT) were enrolled. We selected evaluation criteria for the conduct of a 1:1 propensity score matching (PSM) analysis. Multivariable logistic analysis was used to investigate factors related to frequent PVCs. Furthermore, the determinants of EAT volume and the burden levels of PVCs were evaluated., Results: Patients with PVCs had a significantly larger EAT volume than control patients. EAT volume was significantly larger in male PVC patients with BMI ≥24 kg/m 2 , diabetes mellitus, and E/A ratio <1. EAT volume was independently associated with PVCs. Moreover, the larger EAT volume was an independent predictor for the high burden level of PVCs. We revealed that the risk of high PVC burden level was increased with the rising of EAT volume by restricted cubic splines., Conclusions: EAT volume was larger in frequent PVC patients than in control patients, regardless of other confounding factors. A large EAT volume was independently associated with high burden levels of PVCs. EAT volume may be a new mechanism to explain the pathogenesis of PVCs., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Wang, Jiao, Chen, Guo, Ren, Sun, Sun and Chen.)

Background: Radiofrequency catheter ablation (RFCA) of premature ventricular contractions (PVCs) originating from common locations such as the proximal and middle fascicles of the His-Purkinje system (HPS) has been established as an effective therapy. This report aims to highlight the electrophysiological properties and RFCA of PVCs originating from uncommon locations of the HPS., Methods: Among 57 patients with fascicular PVCs, 3 with fascicular PVCs originating from uncommon sites were retrospectively analyzed., Results: We identified three patients with PVCs originating separately from diseased fascicles, the dead-end tract (DET), and the distal fascicle. In contrast to PVCs originating from the proximal and medial fascicles, the fascicular potentials could not be recorded at the target sites of patients with PVCs originating from diseased fascicles or the distal fascicle during sinus rhythm. However, these PVCs were successfully ablated from the HPS, guided by recording their earliest fascicular potentials in PVCs. PVCs originating from the DET are morphologically consistent with those originating from the proximal left anterior fascicle or the distal left bundle branch. The corresponding tiny sharp potential of the DET could be mapped, and RFCA of the right coronary cusp achieved successful suppression of PVCs., Conclusions: The knowledge of the different electrophysiological characteristics of fascicular PVCs originating from uncommon locations can contribute to precise mapping and ablation. For such arrhythmia, the target site for successful ablation should be identified by earliest fascicular potential., (© 2022. The Author(s).)

Background: Positron emission tomography computed tomography (PET-CT) is not routinely used for premature ventricular complexes (PVCs). Whether specific clinical factors are associated with abnormal PET-CT results is not clear., Methods: The treatment courses and baseline characteristics of consecutive patients in a single center between 2012 and 2021, age > 18 years old, and who received 18 F-fluorodeoxyglucose (FDG) PET-CT imaging for evaluation of PVCs were retrospectively analyzed., Results: A total of 102 patients was included. Of these, 27 patients (26.4%) had abnormal PET-CT and 61 (59.8%) had normal imaging. Abnormal PET-CT findings were associated with non-sustained ventricular tachycardia (NSVT) (95.2% vs. 52.6%, p = 0.001), higher number of PVC morphologies (2.29 ± 0.7 vs. 1.31 ± 0.6, p < 0.001), greater PVC coupling interval dispersion (72.47 ± 66.4 ms vs. 13.42 ± 17.9 ms, p < 0.001), and greater likelihood of fast heart rate dependent PVCs (78.5% vs. 38.2%, p = 0.017). Fourteen (51.8%) patients had an abnormal PET-CT and abnormal late gadolinium enhancement (LGE). Patients with abnormal PET-CT were more frequently treated with immunosuppression (81.4% vs. 3.2%, p < .0001) than with catheter ablation (11.1% vs. 45.9%, p = 0.002) compared to the normal PET-CT group. Over a median follow-up of 862 days (IQR 134, 1407), PVC burden decreased in both groups [from 23 ± 16% to 9 ± 10% (p < 0.001) in abnormal PET-CT group and from 21 ± 15% to 7 ± 10% (p < 0.001) in normal PET-CT group]., Conclusions: Abnormal PET-CT findings were more commonly associated with NSVT, multiform PVCs, greater PVC coupling interval dispersion, and fast heart rate dependent PVCs. LGE was not sensitive for detecting inflammation. Immunosuppression was effective in managing PVCs with abnormal PET-CT., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: Myocardial fibrosis is implicated as a potential substrate responsible for arrhythmias., Objectives: This study aimed to investigate myocardial fibrosis assessed by T1 mapping in patients with apparently idiopathic premature ventricular complexes (PVCs), and to determine the relationship between this tissue biomarker and PVC features., Methods: Patients with frequent PVC (>1,000/24 h) who underwent cardiac magnetic resonance imaging (MRI) between 2020 and 2021 were retrospectively evaluated. Patients were included if they had no indicator of known heart diseases on MRI. Sex- and age-matched healthy subjects underwent noncontrast MRI with native T1 mapping. High PVC burden was defined as the percentage of PVC >20%/24 h., Results: A total of 70 patients and 70 healthy controls were included. Global T1 value was significantly higher in patients than in controls (P < 0.001). Extracellular volume was 26.03% ± 2.16% in the patients. Moreover, global T1 value showed a stepwise increase in PVC tertiles (P = 0.03) but not for extracellular volume (P = 0.85). Patients with a non-left bundle branch block (LBBB) inferior axis morphology showed higher global native T1 values than LBBB inferior axis pattern (P = 0.005). In addition, global T1 values correlated significantly with PVC burden (r = 0.28, P = 0.02). In the multivariate analysis, global T1 value independently correlated with high PVC burden (odds ratio: 1.22 per 10-ms increase, P = 0.02)., Conclusions: Increased global T1, a marker of interstitial fibrosis, was detected in patients with apparently idiopathic PVC and was significantly associated with non-LBBB inferior axis morphology and high PVC burden., Competing Interests: Funding Support and Author Disclosures The study was funded by National Key Research and Development Program of China (2021YFF0501400 and 2021YFF0501404) and National Natural Science Foundation of China (No.81930044). All authors have reported that they have no relationships relevant to the contents of this paper to disclose., (Copyright © 2023 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Aims: This study aims to explore the association between the features of epicardial adipose tissue (EAT) in different zones and premature ventricular complexes (PVCs) originating from different sites by computed tomography (CT)., Methods and Results: A total of 136 patients who underwent radiofrequency ablation for PVCs were incorporated in this study. One hundred and thirty-six matched controls were included in this study using the case-control method (1:1 matching). PVCs were classified into four subgroups: (1) right ventricular outflow tract (RVOT-PVCs), (2) non-RVOT of the right ventricle (RV-PVCs), (3) left ventricular outflow tract (LVOT-PVCs), and (4) non-LVOT of the left ventricle (LV-PVCs). The volume and density of EAT were quantified by CT. Patients with PVCs had a significantly higher volume and lower density of EAT than the controls (P < 0.001). The LVOT-PVCs and LV-PVCs had a higher left ventricle periventricular EAT volume (LV-EATv) proportion (P < 0.05). The right ventricle periventricular EAT volume (RV-EATv) proportion was higher in ROVT-PVCs and LVOT-PVCs (P < 0.05). RVOT-PVC patients had a higher volume ratio and a smaller density differential (P < 0.05). Patients with LVOT-PVCs had a lower volume ratio and the LV-PVCs showed a greater density differential (P < 0.05)., Conclusion: Higher volume and lower density of EAT were significantly associated with frequent PVCs. The RVOT-PVC patients had a higher volume ratio and a smaller density differential. The LVOT-PVCs had a lower volume ratio and the LV-PVCs showed a greater density differential. These suggest a link between EAT structural properties and PVCs and a potential role for regional EAT in the development of PVCs., Competing Interests: Conflict of interest: None declared, (© The Author(s) 2023. Published by Oxford University Press on behalf of the European Society of Cardiology.)

Background: Preoperative prediction of the origin site of premature ventricular complexes (PVCs) is critical for the success of operations. However, current methods are not efficient or accurate enough. In addition, among the proposed strategies, there are few good prediction methods for electrocardiogram (ECG) images combined with deep learning aspects., Methods: We propose ECGNet, a new neural network for the classification of 12-lead ECG images. In ECGNet, 609 ECG images from 310 patients who had undergone successful surgery in the Division of Cardiology, the First Affiliated Hospital of Soochow University, are utilized to construct the dataset. We adopt dense blocks, special convolution kernels and divergent paths to improve the performance of ECGNet. In addition, a new loss function is designed to address the sample imbalance situation, whose cause is the uneven distribution of cases themselves, which often occurs in the medical field. We also conduct extensive experiments in terms of network prediction accuracy to compare ECGNet with other networks, such as ResNet and DarkNet., Results: Our ECGNet achieves extremely high prediction accuracy (91.74%) and efficiency with very small datasets. Our newly proposed loss function can solve the problem of sample imbalance during the training process., Conclusion: The proposed ECGNet can quickly and accurately realize the multiclassification of PVCs after training with little data. Our network has the potential to be helpful to doctors with a preoperative diagnosis of PVCs. We will continue to collect similar cases and perfect our network structure to further improve the accuracy of our network's prediction.

Although PVCs commonly lead to degraded cine cardiac MRI (CMR), patients with PVCs may have relatively sharp cine images of both normal and ectopic beats ("double beats") when the rhythm during CMR is ventricular bigeminy, and only one beat of the pair is detected for gating. MRI methods for directly imaging premature ventricular contractions (PVCs) are not yet widely available. Localization of PVC site of origin with images may be helpful in planning ablations. The contraction pattern of the PVCs in bigeminy provides a "natural experiment" for investigating the potential utility of PVC imaging for localization. The purpose of this study was to evaluate the correlation of the visually assessed site of the initial contraction of the ectopic beats with the site of origin found by electroanatomic mapping. Images from 7 of 86 consecutive patients who underwent CMR prior to PVC ablation were found to include clear cine images of bigeminy. The visually apparent site of origin of the ectopic contraction was determined by three experienced, blinded CMR readers and correlated with each other, and with PVC site of origin determined by 3D electroanatomic mapping during catheter ablation. Blinded ascertainment of visually apparent initial contraction pattern for PVC localization was within 2 wall segments of PVC origin by 3D electroanatomic mapping 76% of the time. Our data from patients with PVCs with clear images of the ectopic beats when in bigeminy provide proof-of-concept that CMR ectopic beat contraction patterns analysis may provide a novel method for localizing PVC origin prior to ablation procedures. Direct imaging of PVCs with use of newer cardiac imaging methods, even without the presence of bigeminy, may thus provide valuable data for procedural planning., (© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)

Background: Intraprocedural coronary angiography (CA) is recommended in patients undergoing ablation in aortic cusps to assess the relation of catheter tip and coronary ostia. In this report, we aimed to compare selective coronary angiography (SCA) through the contact force (CF)-sensing radiofrequency catheter with conventional coronary angiography (CCA) to guide ablation of premature ventricular contractions (PVC)., Methods: This was a retrospective observational cohort study of prospectively collected data of 87 consecutive patients undergoing PVC ablation at a single institution between February 2016 and June 2021. Forty-six patients (53%) underwent SCA and forty-one patients (47%) underwent CCA. Data were consecutively collected case-by-case and entered into a computerized database. Procedural characteristics, complications, and clinical outcomes were compared between the SCA and CCA groups., Results: Successful ablation was achieved in seventy-seven (89%) patients. Total procedure and fluoroscopy time and radiation dose were significantly lower in SCA group (93 ± 22 min vs 102 ± 20 min, p = 0.042; 12 ± 3 min vs 14 ± 4 min, p = 0.030; 3292 ± 1221 μGy m 2 vs 3880 ± 1229 μGy m 2 , p = 0.028, respectively). Median ambulation time was significantly longer in CCA group (6.8 ± 1 h vs 17.8 ± 1.8 h, p = 0.006)., Conclusions: Selective coronary angiography through the CF-sensing ablation catheter to assess the relation between the ablation site and the coronary ostia is feasible and safe. This technique precludes the requirement of an additional arterial access and decreases the total procedure and fluoroscopy time and radiation dose., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: Premature ventricular contraction (PVC) is a frequent kind of arrhythmia that affects around 1% of the general population. While PVC most frequently impairs ventricular function in structurally normal heart, retrograde ventriculo-atrial conduction can occur in people with PVC. These retrograde atrial activations may mimic pulmonary vein-derived atrial ectopies. As a result, PVC may raise the risk of atrial fibrillation (AF) by retrograde ventriculo-atrial conduction. The Four-Dimensional Automated Left Atrial Quantification (4D Auto LAQ) tool is a left atrial analytical approach that utilizes three-dimensional volume data to quantify the volume, as well as LA longitudinal and circumferential strains. The purpose of this study was to determine if clinical diagnosis of PVC is connected with abnormal LA function as determined by LA strain evaluation utilizing a 4D Auto LAQ compared to the healthy population., Methods: The 58 patients with frequent PVCs and 53 healthy volunteers as a control group were enrolled in the study. Imaging was performed using the GE Vivid E95 echocardiography equipment (GE Healthcare; Vingmed Ultrasound, Horten, Norway) equipped with an M5S probe (frequency range: 1.5-4.6 MHz) and a 4V probe (frequency range: 1.5-4.0 MHz). Images were imported into and were selected for analysis using the EchoPAC203 software (GE Healthcare). The analysis mode was selected, followed by the volume and 4D Auto LAQ submodes. Following that, the sample point was positioned in the center of the mitral orifice in each of the three planes. The review function was used to acquire the LA parameters measured by 4D Auto LAQ, including volume and strain parameters., Results: The maximum left atrial volume (LAVmax) and minimal left atrial volume (LAVmin) were significantly higher in the patient group (38.91 ± 9.72 vs. 46.31 ± 10.22, 17.75 ± 4.52 vs. 23.10 ± 7.13, respectively, all p values <.001). On the other hand left atrial reservoir longitudinal strain (LASr), conduit longitudinal strain (LAScd), contraction longitudinal strain (LASct), reservoir circumferential strain (LASr-c), conduit circumferential strain (LAScd-c), and contraction circumferential strain (LASct-c) were significantly lower in patient group (26.64 ± 5.64 vs.19.16 ± 4.58, -19.53 ± 3.72 vs. -11.28 ± 3.47, -10.34 ± 1.56 vs. -4.59 ± 1.49, 30.72 ± 4.04 vs. 19.31 ± 2.60, -19.91 ± 1.78 vs. -13.38 ± 2.85, -15.89 ± 6.37 vs. -9.24 ± 1.63, respectively, all p values <.001)., Conclusions: The present study found that premature ventricular complexes can lead to atrial remodeling as well as ventricular remodeling in patients with PVC and 4D LAQ technology can quantitatively examine left atrial function and determine these alterations early., (© 2022 Wiley Periodicals LLC.)

Aims: Our objective was to explore whether the accuracy of the transitional zone index (TZI) for outflow tract ventricular arrhythmias (OT-VAs) origin is affected by cardiac rotation and the additive value of interventricular septum angle (IVSa) obtained from coronary computed tomography angiography (CCTA)., Methods: Standard 12-lead ECGs of OT-VAs with inferior axis in consecutive patients undergoing both CCTA examination and successful ablation were retrospectively analyzed. The IVSa was defined as an angle between the long axis of IVS and sagittal axis of the body from CCTA., Results: 64 patients (31 men; mean age 54.2 ± 11.6 years) were enrolled. The OT-VAs exhibited right ventricular outflow tract origin in 46 (71.9%) patients and 36 (78.3%) were diagnosed correctly by TZI. The left ventricular outflow tract origin OT-VAs was observed in 18 (28.1%) patients and 16 (88.9%) were diagnosed correctly by TZI. The patients were then divided into TZI correct group (n = 52) and TZI incorrect group (n = 12). In the TZI incorrect group, 11/12 (91.7%) cases were R/S transition in lead V3 with the TZ score during premature ventricular contractions [2.8(2.5-3.4)], and the TZI between -1.5 and 0. The IVSa was significantly larger in the TZI incorrect group than correct group (52.0 ± 6.9° vs. 39.0 ± 6.1°; p &lt; .0001). The IVSa ≥46° predicted TZI incorrect with 92% sensitivity, 94% specificity, and 94% accuracy., Conclusion: The IVSa is a novel cardiac rotation index that reliably improves TZI to differentiate the OT-VAs origin, especially for the OT-VAs with lead V3 R/S transition., (© 2022 Wiley Periodicals LLC.)

Competing Interests: Conflict of interest: None declared.

Context: Idiopathic ventricular arrhythmias (IVAs) are a spectrum of ventricular arrhythmia (VA) without structural heart disease (SHD), that includes premature ventricular contractions (PVCs) and ventricular tachycardia (VT). The clinical characteristics of patients with PVCs or VT remain unclear, including distribution of the origin of arrhythmias, age and gender differences, comorbidities, laboratory tests, and electrocardiographic parameters., Objective: The study intended to compare the clinical characteristics of the right ventricular outflow tract (RVOT)- and left ventricular outflow tract (LVOT)-VT of a large group of consecutive patients, to investigate the distribution of the origin of the arrhythmias, age and gender differences, comorbidities, laboratory-examination results, and echocardiographic parameters., Methods: The research team designed a retrospective study to collect data on the above-mentioned variables., Setting: The study occurred at the Second Hospital of Hebei Medical University in Shijiazhuang, China., Participants: Participants were 774 patients with symptomatic ventricular arrhythmias, 328 males and 446 females with the mean age of 48.6 ± 15.7 years, who underwent catheter ablation between January 2015 and January 2019. Participants were divided into the right ventricular outflow tract (RVOT) group and left ventricular outflow tract (LVOT) group, according to the different origins of their arrhythmias, with 428 participants in the RVOT group and 180 in the LVOT group., Outcome Measures: The research team collected and analyzed the data for the original sites of the IVAs; ages; genders; comorbidities; laboratory examinations, including routine blood tests, liver function, kidney function, blood lipid and potassium; and echocardiographic parameters., Results: Among the 774 participants, 76 had experienced VTs and 698 PVCs. The original site of IVAs was 2.38 times more likely to be in the RVOT than the LVOT, with the ratio for RVOT/LVOT = 2.38. IVAs usually occurred in participants between 50 and 70 years old and exhibited a decreasing incidence after 70 years of age. IVAs derived from the His bundle were more common in older participants, with a mean age of 60.4 ± 10.4 years, while IVAs derived from the fascicular were more common in younger patients, with a mean age of 36.08 ± 16.01 years. Compared with the LVOT group, the RVOT group was younger, 51.91 ± 14.65 years vs 46.95 ± 14.95 years, respectively (P < .001). PVCs in the RVOT group were more common in women, with the ratio of females/males = 2.10, and no gender difference existed in the overall incidence of IVAs in the LVOT group (P > .05). The most common cardiovascular comorbidities of outflow tract ventricular arrhythmias (OTVAs) were hypertension, coronary heart disease, and hyperlipidemia, while the most common noncardiovascular comorbidities were diabetes, ischemic stroke, and thyroid disease. The red-blood-cell counts, hemoglobin, creatinine, and gamma-glutamyl transpeptidase (GGT) of the LVOT group were higher than those from the RVOT, with P = .008, P = .009, P = .001, and P < .001, respectively. The left atrial diameter (LAD), left ventricular end-diastolic diameter (LVEDD), interventricular septal thickness (IVS), and left ventricular posterior wall thickness (LVPWT) in the LVOT group were larger than those in the RVOT group (P <.001), while the LVOT group's left ventricular ejection fraction (LVEF%) was lower than that of the RVOT group., Conclusions: The outflow tract served as the major original site of IVAs, and significant differences existed between participants in the LVOT and RVOT groups in age; gender; comorbidities; results of laboratory examinations, including red-blood-cell counts, hemoglobin, creatinine, and GGT; and echocardiographic parameters, including LVEF%, LAD, LVEDD, IVS, and LVPWT.

Background/aim: Some electrocardiography (ECG) parameters such as Tp-e interval, Tp-e / QT ratio, fragmented QRS (fQRS), and heart rate variability (HRV) are related to cardiovascular mortality and morbidity. We aim to investigate the relation between premature ventricular contraction burden and these parameters on 24-h ECG recording., Materials and Methods: The study is a retrospective investigation of the 24-h Holter ECG and echocardiography of 199 patients who underwent the procedures due to complaints of palpitation. A frequency of < 10% PVCs / 24 h was classified as seldom group (98 patients), while > 10% PVCs / 24 h was designated as frequent group (101 patients)., Results: Tp-e interval was significantly longer (62 [54–78] vs 75 [60–84], p < 0.001), Tp-e / QT ratio was significantly increased (0.18 [0.16–0.20] vs 0.21 [0.18–0.22], p = 0.001) in frequent PVC group. The percentage of fQRS was significantly increased in frequent PVC group (30.6% vs 47.5%, p = 0.015). When the groups were compared, no significant difference was found in HRV time domain indices. Positive correlations were observed between PVC burden and Tp-e (r = 0.304, p < 0.001), Tp-e / QT (r = 0.275, p < 0.001)., Conclusion: Our study showed that Tp-e interval, Tp-e / QT and fQRS are associated with frequency of PVCs. These measurements in patients with PVCs may form part of assessment of cardiovascular risk., Competing Interests: Authors of this study do not have any conflict of interest., (This work is licensed under a Creative Commons Attribution 4.0 International License.)

Background: Sympathetic activation in ischemic heart disease can cause lethal arrhythmias. These often are preceded by premature ventricular complexes (PVCs), which at the cellular level could result from delayed afterdepolarizations., Objective: The purpose of this study was to identify and map vulnerable areas for arrhythmia initiation after myocardial infarction (MI) and to explore the link between PVCs and cellular events., Methods: Anterior-septal wall MI was induced by 120 minutes of coronary occlusion followed by reperfusion (27 MI and 16 sham pigs). After 4 weeks, EnSite™ electroanatomic mapping combined with imaging was performed to precisely locate PVC sites of origin and subsequently record monophasic action potentials. Cardiomyocytes were isolated from different regions to study regional cellular remodeling. Isoproterenol was used as a surrogate for adrenergic stimulation both in vivo and in cardiomyocytes., Results: PVCs originated from the MI border zone (BZ) and occurred at discrete areas with clusters of PVCs within the BZ. At these sites, frequent delayed afterdepolarizations and occasional associated spontaneous action potentials translating to a PVC were present. Cardiomyocytes isolated from the MI BZ exhibited more spontaneous action potentials than cardiomyocytes from remote regions. Sensitivity to adrenergic stimulation was increased in MI, in vivo and in cardiomyocytes. In awake, freely moving MI animals, frequent PVCs, ventricular arrhythmia, and sudden cardiac death occurred spontaneously at moderately elevated heart rates., Conclusion: Post-MI, arrhythmias initiate from discrete vulnerable areas within the BZ, where delayed afterdepolarizations, related to increased adrenergic response of BZ cardiomyocytes, can generate PVCs., (Copyright © 2021 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

Background: Electrocardiographic (ECG) criteria have been proposed to localize the site of origin of outflow region ventricular arrhythmias (VAs). Many factors influence the QRS morphology of VAs and may limit the accuracy of these criteria., Objective: The purpose of this study was to assess the accuracy of ECG criteria that differentiate right from left outflow region VAs and localize VAs within the aortic sinus of Valsalva (ASV)., Methods: One hundred one patients (mean age 52 ± 16 years; 55 [54%] women) undergoing catheter ablation of right ventricular outflow tract (RVOT) or ASV VAs with a left bundle branch block, inferior axis morphology were studied. ECG measurements including V 2 transition ratio, transition zone index, R-wave duration index, R/S amplitude index, V 2 S/V 3 R index, V 1-3 QRS morphology, R-wave amplitude in the inferior leads were tabulated for all VAs. Comparisons were made between the predicted site of origin using these criteria and the successful ablation site., Results: Patients had successful ablation of 71 RVOT and 38 ASV VAs. For the differentiation of RVOT from ASV VAs, the positive predictive values and negative predictive values for all tested ECG criteria ranged from 42% to 75% and from 71% to 82%, respectively, with the V 2 S/V 3 R index having the largest area under the curve of 0.852. Morphological QRS criteria in leads V 1 through V 3 did not localize ASV VAs. The maximum R-wave amplitude in the inferior leads was the sole criterion demonstrating a significant difference between right ASV, right-left ASV commissure, and left ASV sites., Conclusion: ECG criteria for differentiating right from left ventricular outflow region VAs and for localizing ASV VAs have a limited accuracy., (Copyright © 2021 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

Background We have previously developed an intraprocedural automatic arrhythmia-origin localization (AAOL) system to identify idiopathic ventricular arrhythmia origins in real time using a 3-lead ECG. The objective was to assess the localization accuracy of ventricular tachycardia (VT) exit and premature ventricular contraction (PVC) origin sites in patients with structural heart disease using the AAOL system. Methods and Results In retrospective and prospective case series studies, a total of 42 patients who underwent VT/PVC ablation in the setting of structural heart disease were recruited at 2 different centers. The AAOL system combines 120-ms QRS integrals of 3 leads (III, V2, V6) with pace mapping to predict VT exit/PVC origin site and projects that site onto the patient-specific electroanatomic mapping surface. VT exit/PVC origin sites were clinically identified by activation mapping and/or pace mapping. The localization error of the VT exit/PVC origin site was assessed by the distance between the clinically identified site and the estimated site. In the retrospective study of 19 patients with structural heart disease, the AAOL system achieved a mean localization accuracy of 6.5±2.6 mm for 25 induced VTs. In the prospective study with 23 patients, mean localization accuracy was 5.9±2.6 mm for 26 VT exit and PVC origin sites. There was no difference in mean localization error in epicardial sites compared with endocardial sites using the AAOL system (6.0 versus 5.8 mm, P =0.895). Conclusions The AAOL system achieved accurate localization of VT exit/PVC origin sites in patients with structural heart disease; its performance is superior to current systems, and thus, it promises to have potential clinical utility.

Purpose: Aortic cusps might be the source of supraventricular or ventricular arrhythmias. For many years, aortic cusp ablation has been widely used to treat premature ventricular contractions (PVCs) and ventricular tachycardia (VT). However, the data on the outcomes of this procedure in children are limited. The study aimed to convey or describe our own aortic cusp ablation experiences in children and, thus, contribute to the literature., Methods: The focus was pediatric cases of ventricular arrhythmia in which the origin of the PVCs was ablated above the Valsalva. The sample comprised patients who underwent aortic cusp ablation between 2013 and 2018. The demographic characteristics, noninvasive test results, procedure details, and follow-up results for the patients were noted., Results: The 3D EnSite Precision cardiac mapping system and limited fluoroscopy were used. A total of 26 procedures were performed on 22 patients. The mean age was 14.4 ± 3.0 (9-19) years, and the mean weight was 57.3 ± 17.5 (27-99) kg. The mean follow-up period after the first presentation was 38.6 ± 22.9 (3-72) months. There were significant differences in the values of the transition index, V2S/V3R, IIR/IIIR, aVRS/aVLS ratio, and QRS polarity in I at various locations. The most common ablation site was the left coronary cusp (LCC). Radio frequency (RF) ablation, cryoablation, and irrigated RF ablation were found to be effective energy sources in 15, 4, and 3 patients, respectively. Patients who underwent ablation at the LCC-right coronary cusp (RCC) commissure were more likely to present with only VT and to experience worsening symptoms. Twelve patients had previously undergone ablation of the right ventricular outflow tract (RVOT). Ablation in the RVOT had been previously performed in all the patients who eventually underwent ablation at the RCC and the LCC-RCC commissure., Conclusion: Aortic cusp ablation can be safely performed in children. The careful evaluation of previous noninvasive tests provides important data for determining the location. There might be significant differences in the signs and requirements on the basis of the locations during mapping and ablation., (© 2020. Springer Science+Business Media, LLC, part of Springer Nature.)

Purpose: Prior studies reporting efficacy of radiofrequency catheter ablation for complex ventricular ectopy in mitral valve prolapse (MVP) are limited by selective inclusion of bileaflet MVP, papillary muscle only ablation, or short-term follow-up. We sought to evaluate the long-term incidence of hemodynamically significant ventricular tachycardia (VT) or fibrillation (VF) in patients with MVP after initial ablation., Methods: We studied consecutive patients with MVP undergoing ablation for complex ventricular ectopy between 2013 and 2017 at our institution. Of 580 patients with MVP, we included 15 (2.6%, 10 women; mean age 50 ± 14 years, 53% bileaflet) with complex ventricular ectopy treated with initial ablation., Results: Over a median follow-up of 3406 (1875-6551) days or 9 years, 5 of 15 (33%) patients developed hemodynamically significant VT/VF after their initial ablation and underwent placement of an implantable cardioverter defibrillator (ICD). Three of 5 also underwent repeat ablations. Sustained VT was inducible prior to index ablation in all 5 who developed VT/VF, compared to none of the 10 patients who did not develop VT/VF after index ablation (p = 0.002). Complex ventricular ectopy at index ablation was multifocal in all 5 patients who underwent repeat intervention versus 4 of 10 patients (40%) who did not (p = 0.04). All 3 patients with subsequent VT/VF who underwent repeat ablation had a new clinically dominant focus of ventricular arrhythmia and 3 of the patients with ICD had appropriate VT/VF therapies., Conclusions: In the long term, a subset of MVP patients treated with ablation for ventricular arrhythmias, all with multifocal ectopy on initial EP study, develop hemodynamically significant VT/VF. Our findings suggest the progressive nature of ventricular arrhythmias in patients with MVP and multifocal ectopy.

Background: Outflow tract (OT) premature ventricular contractions (PVCs) are commonly found in clinical practice; in most cases, PVCs are benign and observed in structurally normal hearts, not requiring any therapeutic intervention. In this study, we therefore sought to evaluate with cardiac magnetic resonance (CMR) patients with PVC and apparently normal heart at echocardiographic examination, in order to identify possible substrates linked with higher prevalence of arrhythmias or structural heart disease., Methods: Thirty-three consecutive patients with frequent PVCs originating from the ventricular OT (right and left) were enrolled in the study and assessed by echocardiography and CMR. All patients had normal baseline electrocardiogram., Results: CMR showed structural changes in 5 patients out of 33; in 3 cases, areas of fibrosis limited in one case to the middle basal segments of the interventricular septum and in two patients to the middle basal segments of the inferior-lateral wall were found. In 2 other cases, however, late gadolinium enhancement showed significant anomalies characterized in one patient by extensive areas of subepicardial fibrosis of the left ventricle, suitable with arrhythmogenic left dominant dysplasia; in another patient, a marked trabeculation of left ventricular medium apical segments suitable with non-compaction myocardium was present., Conclusions: CMR may identify cases of structural heart disease in subjects with OT PVCs and apparently normal electrocardiogram and echocardiogram examinations. A preliminary screening with CMR may be considered before any further invasive electrophysiology assessment and therapeutic planning.

Background: Premature ventricular beats (PVBs) are not an unusual finding and their interpretation is sometimes challenging. Unfortunately, few data on the characteristics of PVBs that correlate with the risk of an underlying heart disease are available in athletes., Objectives: The aim of this prospective study was to investigate the diagnostic and prognostic value of PVBs characteristics in competitive athletes., Methods: From a cohort of 1751 athletes evaluated at our sports cardiology centre, we enrolled 112 competitive athletes <40 years of age (mean age 21 ± 10 years) and with no known heart disease referred for PVBs. All athletes underwent physical examination, ECG, 12‑lead ambulatory ECG monitoring, exercise testing, and echocardiography. Further investigations including cardiac magnetic resonance were performed for abnormal findings at first-line evaluation or for specific PVBs characteristics., Results: The majority (79%) of athletes exhibited monomorphic PVBs with a fascicular or infundibular pattern (common morphologies). A definitive diagnosis of cardiac disease was reached in 26 athletes (23% of the entire population) and correlated with uncommon PVBs morphology (p < 0.001) and arrhythmia complexity (p < 0.001). The number of PVBs/24-h was lower in athletes with cardiac disease than in those with normal heart (p < 0.05). During the follow-up a spontaneous reduction of PVBs and no adverse events were observed., Conclusions: Infundibular and fascicular PVBs were the most common morphologies observed in athletes with ventricular arrhythmias referred for cardiological evaluation. Morphology and complexity of PVBs, but not their number, predicted the probability of an underlying disease. Athletes with PVBs and negative investigation showed a good prognosis., Competing Interests: Declaration of Competing Interest None., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Background: The study was aimed at exploring the electrophysiological characteristics (EPS) of the optimal ablation site and its relationship with electroanatomic voltage mapping (EVM) in idiopathic premature ventricular contractions (PVCs) originating from the right ventricular outflow tract (RVOT)., Methods: A total of 28 patients with idiopathic RVOT PVCs underwent successful ablation and EVM using a 3D electroanatomical mapping (CARTO) system., Results: Both bipolar and unipolar EVM showed a similar band-like lower-voltage area (LVA) under the pulmonary valve in all the patients; 21.4% of the targets were located in the band-like LVA. 42.9% of the targets were at the border of the band-like LVA on the bipolar voltage map, but unipolar mapping showed that 53.6% of the targets were located in the band-like LVA, and 35.7% of the targets at the border of the band-like LVA. A significant difference was found in both unipolar and bipolar voltage values between the regions within 0-5 mm above the optimal ablation site and the other regions. A similar difference was observed only in unipolar voltage values below the optimal ablation site. At the ablation site, there were frequent occurrences of a fragmented wave and voltage reversion in the bipolar electrograms, frustrated falling limbs, W bottom, and a QS configuration width > 150 ms in the unipolar electrograms., Conclusions: EVM showed that the band-like LVA was an interesting area for the search of the optimal ablation sites of idiopathic RVOT-PVCs, especially the border area. There was focal microscarring around the ablation targets; some characteristics of EPS proved significant for successful ablation., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2021 Zhiyong Zhang et al.)

Frequent premature ventricular contractions (PVCs) can induce cardiomyopathy (PVC CM). We sought to use cardiac magnetic resonance imaging (CMR) to quantify changes in cardiac structure and function of cardiomyopathy patients following catheter ablation for PVCs. Patients undergoing PVC ablation at the Johns Hopkins Hospital with pre-procedural CMR from 2010 to 2018 were included in this study. CMR Images were analyzed to collect information on cardiac structure and function as well as to quantify scar. Of the total 51 included patients, PVC CM (LVEF < 45%) was observed in 51% (n = 29). Of these, 19 had post-ablation ejection fractions quantified, with 78.9% (n = 15) recovering function. Global longitudinal strain was significantly correlated with LVEF (OR 1.831, p < 0.01) but did not predict recovery of function. RV origin of PVCs was more common in the preserved LVEF group but was also significantly correlated with persistently reduced EF post-ablation in the PVC CM group. Scar burden was not correlated with either cardiac function or post-ablation recovery of function. In this cohort, there were no significant CMR findings to predict subsequent recovery of EF after ablation among those with PVC CM. PVC origin in the RV was associated with persistently reduced LVEF after ablation.

Purpose: This study evaluated the efficacy and safety of transcatheter radiofrequency ablation (RFCA) in treating ventricular premature contractions (PVCs) in children, summarized the countermeasures during intraoperative ventricular fibrillation (VF), and improved the safety of ventricular premature treatment., Methods: A retrospective analysis was conducted on 75 children with PVCs who received RFCA in the Second Affiliated Hospital of Wenzhou Medical University from January 2010 to April 2019. Data including age, sex, body weight, ejection fraction, left ventricular end diastolic diameter, burden and number of PVCs/24 h, origin of PVCs, and its complications were collected. Paired t test was used to compare changes in cardiac function before and after surgery., Results: Among the 75 cases treated with RFCA, 68 were successfully ablated, giving a success rate of 90.67%. After ablation, the left ventricular ejection fraction (LVEF) of the children was 69.13 ± 3.81%, which was significantly higher than that before surgery (69.13 ± 3.81% vs. 66.21 ± 3.22%, P = 0.012). One of the patients experienced VF during the operation, with no other complications. The initial locus of origin was the anterior septum of the right ventricular outflow tract, but VF occurred during the ablation process. Mean follow-up time was 39 ± 33 months, with two recurrent cases (2.94%)., Conclusions: Performing RFCA in children is safe and effective, with a low recurrence rate and few complications. VF is not an indication to cease surgery; the key to eliminating complications is repositioning the catheter and finding a more accurate origin point.

The diagnosis of premature ventricular contractions (PVC) is presumptively based on the presence of frequent symptoms. Particularly in patients with a relatively low PVC burden, the relationship between the PVCs and an individual arrhythmia substrate can be challenging to ascertain. Late gadolinium enhancement (LGE) on cardiac magnetic resonance imaging (CMR) has been found to be beneficial in identifying the presence of potential individual arrhythmia substrates even in patients with normal left ventricular function. Consequently, CMR has been useful in risk stratification of patients with PVCs. The authors aimed to demonstrate and discuss the current role and future use of CMR in the diagnostic algorithm to guide PVC ablation.

Background: Little is known about the ablation outcomes of premature ventricular contractions (PVCs) that originate from the periprosthetic aortic valve (PPAV) regions of patients with aortic valve replacement (AVR)., Methods and Results: Our study had 11 patients who underwent catheter ablation for PVCs arising from the PPAV regions (bioprosthetic aortic valve, n = 5; mechanical aortic valve, n = 6). The PVC characteristics, procedure characteristics, and efficacy of ablation were compared with the control group (n = 33). At baseline, the PPAV group had a lower left ventricular ejection fraction (mean [SD], 41% [12%] vs. 51% [8%]; p = .002). The rate of acute ablation success was 90.9% in the PPAV group. Ablation sites were identified above the left coronary cusp (LCC) and right coronary cusp commissure (LRCC) in one PVC, below the prosthetic valve in eight PVCs (four below LCC and four below LRCC), and within the distal coronary sinus in two PVCs. The mean procedure time, fluoroscopy time, and radiation in the PPAV group were all significantly greater than those in the control group (all p < .05). However, the number of radiofrequency ablation energy deliveries was not different. The PPAV group had a long-term success rate compared with the control group (72.7% vs. 87.9%, p = .48) and an increase of left ventricular ejection fraction from 43% to 49% after successful PVC ablation at follow-up (p < .001). Echocardiography showed no significant change in valve regurgitation after ablation. No new atrioventricular block occurred., Conclusion: PVCs arising from PPAV regions can be successfully ablated in patients with prior AVR, without damaging the prosthetic aortic valve and atrioventricular conduction., (© 2020 Wiley Periodicals LLC.)

Premature ventricular contractions (PVCs) in pediatric patients without structural heart disease and normal left ventricular systolic function rarely require therapy, though it is unknown whether these patients have subclinical cardiac dysfunction. Speckle tracking echocardiography is an additional means of evaluating cardiac function in asymptomatic pediatric PVC patients with normal standard measures of left ventricular (LV) function. Asymptomatic pediatric patients (< 21 years) without congenital heart disease, LV ejection fraction (LVEF) ≥ 55% and PVC burden ≥ 5% on 24-h Holter monitor were included. Demographic information, exercise stress test results, standard echocardiographic measures of LV systolic function and PVC morphology by 12-lead ECG were collected. Peak global systolic longitudinal strain (GLS) from apical four-chamber view was analyzed offline. 29 patients were identified (mean age 11.7 ± 5.8 years, 49.2 ± 25.3 kg, 59% male). Mean PVC burden was 12.0 ± 7.0% (range 5-37.5%). 14/29 (48%) had exercise stress testing with evidence of PVCs; 9/14 (64%) had PVC suppression at a mean heart rate (HR) of 160 ± 23 bpm and 5/14 (36%) did not suppress at a mean maximum HR of 188 ± 9 bpm. All patients had normal strain values by speckle tracking echocardiography (mean LV GLS - 22.5 ± 2.0%, LV global circumferential strain - 25.3 ± 3.9 and RV GLS - 24.1 ± 3.0%). There was no correlation between PVC burden and cardiac function parameters. Asymptomatic pediatric patients without structural heart disease, preserved LVEF/shortening fraction and PVC burden ≥ 5% demonstrated normal cardiac function including strain patterns indicating no evidence of subclinical cardiac dysfunction. Larger scale studies and longitudinal evaluation of left ventricular function using speckle tracking echocardiography is warranted in this population.

Background: Postextrasystolic potentiation (PESP)-associated augmentation in left ventricular-aorta pressure gradient (LVAoG) observed after incidental premature ventricular contraction (PVC) during resting echocardiography is similar to dobutamine stress echocardiography (DSE)-associated augmentation in LVAoG in patients with low-flow, low-gradient (LF-LG) aortic stenosis (AS). What is not known is whether a similar relationship exists when unintended PVC causes PESP during cardiac catheterization in patients with AS., Methods: We retrospectively reviewed all catheterizations performed for patients with at least moderate AS who had LVAoG assessment. Univariate and multivariate analyses were conducted to determine the predictors of pre- and post-PVC mean LVAoG ≥ 40 mmHg., Results: Between September 2015 to September 2017, of 140 individuals undergoing cardiac catheterization, 34 met study criteria. Mean pre-PVC gradient was 38.9 ± 22.8 mmHg. All patients exhibited PESP-associated augmentation of LVAoG by an average of 28 ± 12%. In multivariate analysis, the only significant predictor of post-PVC mean LVAoG ≥ 40 mmHg was preserved LV function (OR 6.81; 95% CI 1.41-32.82, p = 0.02). Inability to generate ≥ 40 mmHg of mean LVAoG post-PVC had 100% specificity for nonsevere AS in our observational cohort., Conclusions: Unintended but interpretable PVCs occurred in one in four patients with AS undergoing cardiac catheterization with measurable hemodynamics. All of our patients with PVCs, regardless of underlying LVEF, exhibited PESP-associated augmentation of LVAoG. Our exploratory analysis suggests that inability to generate ≥40 mmHg of mean LVAoG post-PVC is highly specific for nonsevere AS., Competing Interests: Declaration of competing interest No grants, contracts, and other forms of financial support were provided for this project. The authors have no conflicts of interest to note., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Premature ventricular complex (PVC) is common in the general population. Symptoms vary from none to pronounced. The prognostic significance of PVC's depends on the presence of underlying structural heart disease. The clinical evaluation in patients with PVC aims at excluding structural heart disease and usually involves transthoracic echocardiogram and Holter. Patients without structural heart disease usually have a good prognosis. Frequent PVC's may cause impaired left ventricular function, which usually is reversible after treatment with drugs or ablation. A 12-lead ECG provides important information about PVC localization, however anatomical factors such as the heart's localization in the thorax as well as electrode placement and pharmacological treatment may affect the ECG appearance. In symptomatic patients with or without left ventricular impairment, pharmacological treatment or catheter ablation is indicated. However, in most cases the main goal is to reasure the patient of the good prognosis. To summarize, treatment of choice depends on symptoms, comorbidities, left ventricular function and patient's choice.

Background: Cardiac magnetic resonance (CMR) characteristics of ventricular radiofrequency ablation (RFA) lesions have only been incompletely defined., Aim: To determine the detectability and imaging characteristics of ventricular RFA lesions in an unselected patient cohort undergoing ventricular arrhythmia ablation., Methods and Results: A retrospective chart review (n = 249) identified 36 patients with either pre-/postablation CMR (n = 14) or only postablation CMR (n = 22). Ablation lesions could be identified in 50% (n = 18) of patients. Nonvisualized lesions had more preexisting transmural late gadolinium enhancement (LGE) >75% at the ablation sites (21% vs 0.0%, P = .042), more prevalent ICD artifact (50% vs 0%, P = .001), and lower ejection fraction (35.8 ± 14.2% vs 45.3 ± 13.4%, P = .048). Early CMR imaging demonstrated a central "black" signal void (microvascular obstruction [MVO], n = 12, 67%) up to 32 days post-RFA, whereas late imaging showed a homogenously "white" gadolinium enhancement pattern (n = 6, 33%). MVO was only observed in nonfibrotic myocardium without preexisting LGE (n = 12) but was not observed in the scar with preexisting LGE (n = 3, P = .002) suggesting different wash-in/wash-out kinetics in scar/nonscar myocardium. Signal intensity (1909 vs 2534, P = .009) and contrast-to-noise ratio (-7.8 vs 16.3, P = .009) were significantly different between MVO and LGE lesions, respectively., Conclusion: Ventricular ablation lesions visualization is negatively affected by preexisting transmural scar, ICD artifact, and low ejection fraction. The transition of "black" MVO appearance to "white" LGE appearance on CMR occurs around 1 month following ablation, suggesting a change in histological characteristics of ablation lesions. This may affect the utility of CMR in the evaluation of the ventricular lesions, when undergoing real-time or repeat VT ablations., (© 2020 Wiley Periodicals, Inc.)

Recurrent ventricular arrhythmias (VAs) are a leading cause of cardiovascular morbidity and mortality. In the last three decades, important advancements have occurred in the understanding of the mechanisms of recurrent VAs, their prognostic implications in different clinical contexts, and their treatment options. VAs occur in structurally normal hearts as well as in patients with underlying heart disease, but the latter group has a particularly high risk of recurrent VAs. Catheter ablation offers the possibility of cure for a substantial proportion of patients. Research has focused on identifying optimal targets for ablation, correlating the underlying structural abnormalities with the site of origin of VAs, and determining the optimal procedural approach. Ablation therapy can be life-saving in select patients with high burden of repetitive VAs or advanced heart failure syndromes. This article focuses on clinical aspects of catheter ablation of VAs, particularly the selection and clinical management of patients undergoing catheter ablation procedures and expected outcomes.

Background: The presence and significance of neural remodeling in premature ventricular contraction-induced cardiomyopathy (PVC-CM) remain unknown., Objectives: This study aimed to characterize cardiac sympathovagal balance and proarrhythmia in a canine model of PVC-CM., Methods: In 12 canines, the investigators implanted epicardial pacemakers and radiotelemetry units to record cardiac rhythm and nerve activity (NA) from the left stellate ganglion (SNA), left cardiac vagus (VNA), and arterial blood pressure. Bigeminal PVCs (200 ms coupling) were applied for 12 weeks to induce PVC-CM in 7 animals then disabled for 4 weeks to allow complete recovery of left ventricular ejection fraction (LVEF), versus 5 sham controls., Results: After 12 weeks of PVCs, LVEF (p = 0.006) and dP/dT (p = 0.007) decreased. Resting SNA (p = 0.002) and VNA (p = 0.04), exercise SNA (p = 0.01), SNA response to evoked PVCs (p = 0.005), heart rate (HR) at rest (p = 0.003), and exercise (p < 0.04) increased, whereas HR variability (HRV) decreased (p = 0.009). There was increased spontaneous atrial (p = 0.02) and ventricular arrhythmias (p = 0.03) in PVC-CM. Increased SNA preceded both atrial (p = 0.0003) and ventricular (p = 0.009) arrhythmia onset. Clonidine suppressed SNA and abolished all arrhythmias. After disabling PVC for 4 weeks, LVEF (p = 0.01), dP/dT (p = 0.047), and resting VNA (p = 0.03) recovered to baseline levels. However, SNA, resting HR, HRV, and atrial (p = 0.03) and ventricular (p = 0.03) proarrhythmia persisted. There was sympathetic hyperinnervation in stellate ganglia (p = 0.02) but not ventricles (p = 0.2) of PVC-CM and recovered animals versus sham controls., Conclusions: Neural remodeling in PVC-CM is characterized by extracardiac sympathetic hyperinnervation and sympathetic neural hyperactivity that persists despite normalization of LVEF. The altered cardiac sympathovagal balance is an important trigger and substrate for atrial and ventricular proarrhythmia., (Published by Elsevier Inc.)

Background: Current maneuvers for differentiation of atrioventricular node reentry tachycardia (AVNRT) and atrioventricular reentry tachycardia (AVRT) lack sensitivity and specificity for AVRT circuits located away from the site of pacing. We hypothesized that a premature His complex (PHC) will always perturb AVRT because the His bundle is obligatory to the circuit. Further, AVNRT could not be perturbed by a late PHC (≤20 ms ahead of the His) due to the retrograde His conduction time. Earlier PHCs can advance the AVNRT circuit but only by a quantity less than the prematurity of the PHC., Methods: High-output pacing at the distal His location delivered PHCs. AVRT was predicted when late PHCs perturbed tachycardia or when earlier PHCs led to atrial advancement by an amount equal or greater than the degree of PHC prematurity., Results: Among the 73 supraventricular tachycardias, the test accurately predicted AVRT (n=29) and AVNRT (n=44) in all cases. Late PHC advanced the circuit in all 29 AVRTs and none of the AVNRTs (sensitivity and specificity, 100%). With earlier PHCs, the degree of atrial advancement was equal or greater than the PHC prematurity in 26/29 AVRTs and none of the AVNRTs (90% sensitivity and 100% specificity). The mean prematurity of the PHC required to perturb AVNRT was 48 ms (range, 28-70 ms) and the advancement less than the prematurity of the PHC (mean, 32 ms; range, 18-54 ms)., Conclusions: The responses to PHCs distinguished AVRT and AVNRT with 100% specificity and sensitivity.

Background: Because premature ventricular contractions (PVCs) are one of the most common arrhythmias, but with unclear causative mechanisms, we studied the hemodynamic features that can cause symptomatic PVCs.Methods and Results:We studied 109 patients (48 males, age 60±19 years) with frequent monomorphic PVCs and no structural heart disease. The left ventricular inflow diastolic filling velocity was recorded by transthoracic echocardiography (TTE) at the time of PVCs in all patients. We assessed the PVC E wave flow (E wave velocity×duration at PVC). A total of 38 patients (35%) had PVC-related symptoms (19 palpitations, 12 pulse deficit, 6 shortness of breath, 6 malaise, 1 syncope). These patients showed reduced PVC E wave flow (9.3±6.0 vs. 14.6±6.5 cm, P<0.0001), and reduced PVC stroke volume (20.5±10.8 vs. 29.9±17.2 mL, P=0.0030). In the multivariate analysis, only reduced PVC E wave flow was independently associated with PVC-related symptoms (P=0.00349, odds ratio: 1.134029, each 1.0 cm increase in PVC E wave flow, 95% confidence interval: 1.040726-1.247544)., Conclusions: Decreased E wave flow at the time of PVC was independently related with PVC-related symptoms in patients with PVCs. The LV contraction at the time of inadequate filling might be a cause of PVC-related symptoms.

Background: Premature ventricular complexes (PVCs) are the most common form of ventricular arrhythmia in the general population. While in most cases PVCs represent a primitive phenomenon with benign behavior, in a non-negligible proportion of subjects frequent PVCs may be epiphenomenon of underlying occult heart diseases, requiring special medical attention since they have been resulted linked to increased total and cardiac mortality. Nevertheless, PVCs themselves, when incessantly frequent, may be responsible for left ventricular dysfunction in otherwise normal heart. Aim of this narrative review is to update current knowledge on the general approach to patients with frequent PVCs on the basis of available data, with a special focus on the value of imaging., Hypothesis: Routine diagnostic work-up not infrequently miss subtle concealed arrhythmic substrate, leading to erroneously refer to such arrhythmias as to "idiopathic"., Methods: Literature search of PVCs articles was conducted in PubMed and Scopus electronic database., Results: Conflicting data arise from literature about the true clinical significance of idiopathic PVCs. There is growing body of data providing evidence that more advanced non-invasive imaging modalities, such as cardiac magnetic resonance, have an incremental diagnostic and prognostic value. On the other hand, in some cases the prognostic significance of isolated subtle myocardial structural abnormalities in patients with PVCs, still remains area of uncertainty., Conclusion: In selected subjects with PVCs and high-risk features for concealed arrhythmic substrate, traditional assessment to rule out the presence of heart disease, including surface ECG and transthoracic echocardiography, should be implemented with more advanced cardiovascular imaging modalities., (© 2019 The Authors. Clinical Cardiology published by Wiley Periodicals, Inc.)

Background: Catheter ablation of ventricular arrhythmias (VAs) arising from the left ventricular Summit (LVS) is challenging and requires high-dose fluoroscopy to limit vascular damage of the coronary arteries. Ionizing radiation can increase the incidence of malignancies to both patient and operator. This study describes outcomes of catheter ablation of LVS VAs using intracardiac echo-facilitated 3D electroanatomical mapping (ICE-3D) to avoid fluoroscopy., Methods: Twenty-six patients (47 ± 17 years old; 52% males; median ejection fraction 55 ± 13%) with premature ventricular contractions or ventricular tachycardia underwent catheter ablation. VAs were localized using ICE-3D with arrhythmia foci being mapped at the LVS. Focal ablation was performed using a 3.5-mm open-irrigated, contact force sensing radiofrequency catheter., Results: Acute success and recurrence rates were 84% and 24%, respectively. Holter burden was significantly reduced (24 ± 15% to 1.5 ± 2%; P = 0.01) after ablation. The use of zero fluoroscopy was achieved in 100% of cases. No major complications were observed., Conclusions: Zero fluoroscopy catheter ablation of LVS VAs using ICE-3D mapping is feasible and effective.

The major sites of origins of idiopathic ventricular arrhythmias have been elucidated. Idiopathic ventricular arrhythmias most often present as premature ventricular contractions (PVCs) with a focal mechanism, and commonly occur without structural heart disease. Idiopathic ventricular arrhythmias usually originate from specific anatomical structures, commonly endocardial but sometimes epicardial and exhibit characteristic electrocardiograms (ECGs) based on their anatomical background. There are general and specific ECG characteristics that can localize the site of idiopathic PVC origins. The general ECG characteristics include the bundle branch block pattern, axis, QRS polarity in lead V6, QRS duration, precordial transition, maximal deflection index, and so forth. They can roughly localize the site of idiopathic PVC origins. Several major sites of idiopathic PVC origins are located close to each other, and specific ECG characteristics are helpful for localizing the site of origins more accurately in those PVCs. Twelve-lead surface ECG algorithms usually can localize the site of idiopathic PVC origins with a high accuracy, but their accuracy can be limited by the patients' physique, heart rotation, specific conduction properties, presence of structural heart disease, and so forth. This review describes an overview of the approaches to the 12-lead surface ECG localization of idiopathic PVCs, and also discusses their caveats and limitations., (© 2019 Wiley Periodicals, Inc.)