Ablation Of Premature Ventricular Contractions Research Articles

Abstract 14421: Limitations of Using Unipolar Signals to Guide Outflow Tract Premature Ventricular Contraction Ablation

Introduction: Unipolar electrogram (EGM) signals are universally used to annotate earliest activation and guide ablation (Abl) of focal arrhythmias. However, their utility in mapping PVCs is limited given 3-dimensionality of wave front propagation, especially when the source is intramural. Hypothesis: 1) earliest onset of bipolar activation would better guide mapping and Abl in these cases, versus maximum unipolar dV/dt or QS morphology; and 2) differences would be greater for intramural outflow tract (OT) PVCs versus those eliminated with RVOT Abl only. Methods: Consecutive patients undergoing successful RVOT or RVOT+LVOT PVC Abl at our center from 2017-2020 were retrospectively analyzed. Bipolar and Unipolar EGMs at successful Abl sites were compared. Results: Of 71 patients, 41 had only RVOT and 30 had RVOT + LVOT Abl. All had acute and long-term PVC suppression over mean 22.6 ± 11.6 month follow-up. Mean EGM difference was 7.6 ± 4.7 ms in the RVOT group vs 18.9 ± 10.5 ms in RVOT+LVOT group (p<0.01). QS unipolar EGM was seen in 95% of RVOT patients, 88% of which were at the anterior RVOT/crux, vs 40% of RVOT+LVOT patients (p<0.016). Activation was equally earliest from the posteroseptal RVOT and adjacent LVOT site in 73%, and most of these sites did not have a QS unipolar EGM (Figure). Conclusions: Bipolar EGM activation timing guided successful ablation of OT PVCs better than unipolar EGM analysis. A QS unipolar EGM did not reliably predict best ablation sites, especially for intramural PVCs.

Autoimmune Myocarditis and Arrhythmogenic Mitral Valve Prolapse: An Unexpected Overlap Syndrome

Background: both myocarditis and mitral valve prolapse (MVP) are known uncommon causes of ventricular arrhythmias in young patients. Aim: to report the first clinical case of endomyocardial biopsy (EMB)-proven autoimmune myocarditis and associated arrhythmogenic MVP in a patient with recurrent ventricular fibrillation (VF) episodes. Methods: myocarditis was diagnosed both by cardiac magnetic resonance (CMR) and EMB. Arrhythmogenic MVP was documented by transthoracic echocardiogram, CMR, and electroanatomical mapping of the trigger premature ventricular contractions (PVCs). Results: a 22-year-old woman underwent immunosuppressive therapy after EMB-proven diagnosis of autoimmune myocarditis with VF onset and early implantable cardioverter defibrillator (ICD) placement. Three years later, she experienced two VF recurrences and persistent PVCs, despite no signs of myocarditis recurrence. An echocardiogram revealed bileaflet MVP with high arrhythmic risk features. Finally, electroanatomical mapping and ablation of the trigger PVC were successfully performed. Conclusion: in patients with recurrent VF episodes despite evidence-based medical treatment for myocarditis, MVP should be considered as an alternative arrhythmogenic substrate, and warrants early ICD implant and PVC-targeted therapy.

Non-invasive mapping reduces procedure duration for catheter ablation of premature ventricular contractions using 12 lead ECG information: results from a prospective case-control study

Abstract Background Premature ventricular complexes (PVCs) result from early depolarisation of myocardial tissue in the ventricles and can ultimately lead to PVC-induced cardiomyopathy. Catheter ablation aims to completely eliminate the PVCs and is usually carried out using sequential activation mapping techniques. We report the results of a prospective case-control trial using the non-invasive, simultaneous 3D mapping system View into Ventricular Onset (VIVO) in combination with a 12 lead Holter ECG recording for catheter ablation of PVC. Methods and results A total of 16 patients (mean age 52.1±20.8 years, all structurally normal hearts, were enrolled and underwent VIVO mapping as a preparation of their invasive PVC ablation. Pre-ablation PVC burden had a median of 18.7% (IQR; 9.94 – 24.35). All but one patient (with very low PVC burden and epicardial origin) underwent a catheter ablation attempt guided by the 3D non-invasive maps integrated as VTK files in to the EAM. In 13/15 patients, acute elimination of the PVC was achieved which resulted in a PVC burden of <0.1% at 3 months' time. Procedure time amounted to in median 106 minutes (IQR 92.5 – 135.5), whereas in an age- and gender-matched control cohort (2:1) procedure time was significantly longer (145 (123.0 – 190.5). Conclusion Ward-based non-invasive 3D mapping (VIVO) of the origin of PVCs in patients with structurally normal hearts successfully guided the invasive ablation procedure and significantly reduced the invasive procedure time, as compared to a contemporary age- and gender-matched control cohort. Funding Acknowledgement Type of funding sources: Private company. Main funding source(s): Catheter Precision 3D non-invasive mapping concept

Catheter ablation of premature ventricular contractions originating from kissing papillary muscles.

Very thick left ventricular papillary muscles (PAMs) may kiss each other and premature ventricular contractions (PVCs) can originate from the sides of the PAMs facing each other. In such a setting, mapping of those PVCs is confusing and rendering catheter ablation challenging.

Premature ventricular contraction ablation for treatment of heart failure.

The association of persistent tachyarrhythmias, “idiopathic” cardiomyopathy (ICM), and heart failure (HF) was first described about a century ago. Subsequent observations of the reversibility of ICM and HF after successful treatment of tachyarrhythmias provided the proof of concept that ICM and HF could be consequences of tachycardia, contrary to the traditional teaching that ICM and HF were causative to tachyarrhythmias due to preexisting pathophysiological substrates. Similarly, premature ventricular contractions (PVCs) were viewed as markers of underlying cardiac dysfunction rather than causes of cardiac dysfunction.

B-PO02-135 LEFT VENTRICLE POSTERIOR SUPERIOR PROCESS ECTOPY: RISK OF AV NODE BLOCK DURING ABLATION

Premature ventricular contractions (PVC) originating from the highest portion of the inferior left ventricular (LV) septum are infrequent and challenging to treat with catheter ablation (CA). The incidence and CA risks are ill-defined. We sought to determine the incidence of PVC originating from the posterior superior process (PSP) at our institution. We reviewed our records retrospectively between 1/2018 and 10/2020 for all PVC ablations. We selected all patients who underwent PVC ablation from the PSP region. 370 patients underwent PVC were identified from institutional ventricular tachycardia database. Of the total cohort, four patients (1%) had PVCs ablated from the PSP region. Three of four were male, normal LVEF average 51% and only one had myocardial scarring on imaging studies. Despite different PVC morphologies, EKG had common characteristics including monophasic R in lead I, rS in lead II and slow downsloping QS in aVR (the “RI-rSII-QSaVR” triad). Acutely successful ablation was performed in all four cases. In all but one case, RF ablation at the earliest mapping site was associated with either transient delay in AV conduction or accelerated junctional rhythm. In 6 months follow up, none of the patients had arrhythmia recurrence. Prolonged monitoring in two patients indicated high degree AV block at sleep but none meet the criteria for pacing. PVCs originating from the PSP are rare, occurring in about 1% of referred patients. Even when approached from the left side, attention to proximity to the compact AV node is warranted when ablating in the PSP region. Despite these concerns, success of ablation is high.

The QRS-right ventricular apex interval as acut-off value to differentiate the origin of outflow tract premature ventricular complexes.

Many electrocardiography (ECG) criteria have been proposed for the localization of outflow tract premature ventricular contractions (PVCs); however, in some cases, it is difficult to accurately localize the origin of PVCs using the surface ECG. The authors aimed to study the QRS-right ventricular apex (RVA) interval measured during electrophysiological study and its role in the differentiation between different sites of origin of outflow tract PVCs. The study included 90patients (81females, mean age 37.20 ± 7.87) referred for outflow tract PVC ablation. The authors measured the interval from the onset of the earliest QRS complex of the PVCs to the distal RVA intracardiac signal (the QRS-RVA interval) during the electrophysiological study and correlated this interval with the origin of outflow tract PVCs as identified by successful ablation during the procedure. The QRS-RVA interval was significantly longer in PVCs originating from the left ventricular outflow tract (LVOT) compared to the right ventricular outflow tract (RVOT) (67.33 ± 7.56 for LVOT PVCs vs. 37.11 ± 4.34 for RVOT PVCs, p < 0.001). Receiver operating characteristic (ROC) analysis showed that aQRS-RVA interval ≥ 48 ms predicted an LVOT origin of PVCs. Ashorter interval was noted in PVCs originating from the RVOT free wall rather than the septal RVOT wall, and ashorter interval was also noted in LVOT PVCs originating from the right coronary cusp as compared to other LVOT PVCs, although these differences did not reach statistical significance. Measuring the QRS-RVA interval is asimple and accurate method for differentiating the origin of outflow tract PVCs during an electrophysiological study. AQRS-RVA interval ≥ 48 ms predicts an LVOT origin of PVCs rather than an RVOT origin.

Catheter Ablation of Premature Ventricular Contractions Originated from Right Ventricular Outflow Tract by Using 3-dimentional Mapping System

Catheter Ablation of Premature Ventricular Contractions Originated from Right Ventricular Outflow Tract by Using 3-dimentional Mapping System

Pattern Matching Filter and multielectrode mapping catheter - A new approach for complex premature ventricular contraction ablation.

Our goal was to assess usefulness of Pattern Matching Filter (PMF) software combined with the PentaRay catheter for complex premature ventricular contraction (PVC) ablation. A prospective observational study of consecutive patients referred for complex PVC ablation at our tertiary center from January to September 2018. Patients underwent ablation using a pre-specified mapping strategy with the PMF and the PentaRay catheter (PVCs with ≥97% correlation with the template morphology were collected). Procedural endpoints and acute and 12-months success rates were assessed and compared to a retrospective cohort of patients who also underwent a complex PVC ablation with standard activation mapping performed with a Thermocool SmartTouch catheter. During the nine-month enrollment period, seven patients fulfilled our inclusion criteria, while there were four patients in the control group. Patients treated with the PMF and PentaRay had a fivefold number of points acquired (507±213 vs. 90±62) and a halved procedure time (67±42 vs.130±54 min), required a shorter radiofrequency ablation time (294±112 vs.706±613 sec) and had a higher overall success rate (100% vs.75%) when compared to the standard approach. No major complications occurred in either group. In this first study assessing the combined use of the PentaRay catheter and the PMF for complex PVCs ablation, we demonstrate how this approach can improve the level of detail, accuracy and reliability of the activation map, while reducing the number of radiofrequency applications and procedural time. Further studies are warranted to confirm whether this approach can lead to improved outcomes.

Impact of age on catheter ablation of premature ventricular contractions

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Catheter ablation (CA) of frequent premature ventricular contractions (PVC) is increasingly performed in older patients as the population ages. Purpose The purpose of this study was to assess the impact of age on procedural characteristics, safety and efficacy on PVC ablations. Methods Consecutive patients with symptomatic PVCs undergoing CA between 2015 and 2020 were evaluated. Acute ablation success was defined as the elimination of PVCs at the end of the procedure. Sustained success was defined as an elimination of symptoms, and ≥80% reduction of PVC burden determined by Holter-ECG during long-term follow. Patients were sub-grouped based on age (&amp;lt; 65 years vs. ≥ 65 years). Results A total of 114 patients were enrolled (median age 64 years, 71% males) and followed up for a median duration of 228 days. Baseline and procedural data were similar in both age groups. A left-sided origin of PVCs was more frequently observed in the elderly patient group compared to younger patients (83% vs. 67%, p = 0.04, Figure 1). The median procedure time was significantly shorter in elderly patients (160 min vs. 193 min, p = 0.02). The rates of both acute (86% vs. 92%, p = 0.32) and sustained success (70% vs. 71%, p = 0.90) were similar between groups. Complications rates (3.7%) did not differ between the two groups. Conclusion In a large series of patients with a variety of underlying arrhythmia substrates, similar rates of acute procedural success, complications, and ventricular arrhythmia-free-survival were observed after CA of PVCs. Older age alone should not be a reason to withhold CA of PVCs. Abstract Figure 1

Three-dimensional late gadolinium enhancement increases the diagnostic yield of cardiovascular magnetic resonance to detect low voltage in the right ventricular outflow tract

Abstract Funding Acknowledgements Type of funding sources: None. Background Cardiac magnetic resonance (CMR) using late gadolinium enhancement (LGE) fails to detect scar tissue in patients with electroanatomical abnormalities and biopsy-proven structural heart disease. It has shown conflicting data regarding existence of structural abnormalities in patients with idiopathic premature ventricular contractions (PVCs) from the right ventricular outflow tract (RVOT). Three- dimensional (3D) LGE enables high-spatial resolution more appropriate to the thin-walled right ventricle than two-dimensional (2D) LGE. Objective Our aim was to evaluate if the use of 3D-LGE would improve the performance of CMR to detect low voltage areas in the RVOT of patients with PVCs. Methods Since May 2020 we performed 3D-LGE CMR in 11 consecutive patients that underwent ablation of frequent PVCs. A control group of 11 consecutive patients that underwent catheter ablation by the same operator and had a 2D-LGE CMR performed before ablation was also studied. All patients had normal 2D-LGE CMR. A 3D electroanatomical bipolar voltage map of the RVOT was performed in sinus rhythm (0.5 mV-1.5 mV colour display). Areas with electrograms &amp;lt;1.5 mV represented the LVA. The area adjacent to the pulmonary valve usually displays voltage between 0.5 and 1.5 mV and is classified as transitional-voltage zone. Presence of LVAs outside this transitional-voltage zone were estimated. We compared the accuracy of CMR for detecting LVA in the two groups: 3D LGE and 2D LGE. Results The median number of points used for the voltage map was 344 (242-450). 18 patients (82%) displayed LVAs. The site of origin of the PVCs was the RVOT in 17 patients and the left ventricular outflow tract (LVOT) in 5. Comparison between groups is displayed in the table. 2D LGE CMR failed to demonstrate abnormalities of the RVOT in any of the patients that presented with LVAs. 3D CMR showed presence of fibrosis (Figure) in 3 out of 9 patients with LVAs (33%). Conclusion CMR using 3-D LGE techniques showed an increased power to diagnose structural abnormalities. This technique may be a better choice in initial stages of RVOT disease. All sampleN = 223D-LGE CMRN = 112D-LGE CMRN = 11p-valueAge in years, median (Q1-Q3)47 (35-68)62 (34-55)42 (34-55)0.243Male gender, n (%)8 (36)3 (27)5 (46)0.330PVCs RVOT/LVOT17/59/28/30.500Nº points in the map, median (Q1-Q3)344 (242-450)350 (259-450)300 (158-345)0.076Low voltage areas, n (%)18 (82)9 (82)9 (82)0.707Abstract Figure.

Cardiac MRI structural and functional predictors of left ventricular ejection fraction recovery following PVC catheter ablation

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.

Efficacy of catheter ablation for premature ventricular contractions in arrhythmogenic right ventricular cardiomyopathy.

Premature ventricular contractions (PVCs) may be found in any stage of arrhythmogenic right ventricular cardiomyopathy (ARVC) and have been associated with the risk of sustained ventricular tachycardia (VT). To investigate the role of PVC ablation in ARVC patients. We studied consecutive ARVC patients who underwent PVC ablation due to symptomatic high PVC burden. Mean daily PVC burden and antiarrhythmic drug (AAD) use were assessed before and after the procedure. Complete long-term success was defined as more than 80% reduction in PVC burden off of membrane-active AADs. Eight patients (37 ± 15 years; 4 males) underwent PVC ablation. The mean daily PVC burden before ablation ranged from 5.4% to 24.8%. A total of 7 (87.5%) patients underwent epicardial ablation. Complete acute elimination of PVCs was achieved in 4 (50%) patients (no complications). The mean daily PVC burden variation ranged from an 87% reduction to a 26% increase after the procedure. Over a median follow-up of 345 days (range: 182-3004 days), only one (12.5%) patient presented complete long-term success, and 6 (75%) patients either maintained or increased the need for Class I or Class III AADs. A total of 2 (25%) patients experienced sustained VT for the first time following the ablation procedure, requiring repeat ablation. No death or heart transplantation occurred. PVC ablation was not associated with a consistent reduction of the PVC burden in ARVC patients with symptomatic, frequent PVCs. PVC ablation may be reserved for highly symptomatic patients who failed AADs. Additional investigation is required to improve the efficacy of PVC ablation in ARVC patients.

Catheter ablation of short-coupled variant of torsade de pointes

BackgroundThe short-coupled variant of torsade de pointes (sc-TdP) is a malignant arrhythmia that frequently presents with ventricular fibrillation (VF) electrical storm. Verapamil is considered the first-line therapy of sc-TdP while catheter ablation is not widely adopted. The aim of this study was to determine the origin of sc-TdP and to assess the outcome of catheter ablation using 3D-mapping.Methods and resultsWe retrospectively analyzed five patients with sc-TdP who underwent 3D-mapping and ablation of sc-TdP at five different institutions. Four patients initially presented with sudden cardiac arrest, one patient experienced recurrent syncope as the first manifestation. All patients demonstrated a monomorphic premature ventricular contraction (PVC) with late transition left bundle branch block pattern, superior axis, and a coupling interval of less than 300 ms. triggering recurrent TdP and VF. In four patients, the culprit PVC was mapped to the free wall insertion of the moderator band (MB) with a preceding Purkinje potential in two patients. Catheter ablation using 3D-mapping and intracardiac echocardiography eliminated sc-TdP in all patients, with no recurrence at mean 2.7 years (range 6 months to 8 years) of follow-up.Conclusion3D-mapping and intracardiac echocardiography demonstrate that sc-TdP predominantly originates from the MB free wall insertion and its Purkinje network. Catheter ablation of the culprit PVC at the MB free wall junction leads to excellent short- and long-term results and should be considered as first-line therapy in recurrent sc-TdP or electrical storm.Graphic abstract

Impact of age on catheter ablation of premature ventricular contractions.

Catheter ablation (CA) of frequent premature ventricular contractions (PVC) is increasingly performed in older patients as the population ages. The aim of this study was to assess the impact of age on procedural characteristics, safety and efficacy on PVC ablations. Consecutive patients with symptomatic PVCs undergoing CA between 2015 and 2020 were evaluated. Acute ablation success was defined as the elimination of PVCs at the end of the procedure. Sustained success was defined as an elimination of symptoms, and ≥80% reduction of PVC burden determined by Holter-electrocardiogram during long-term follow. Patients were sub-grouped based on age (<65 vs. ≥65 years). A total of 114 patients were enrolled (median age 64 years, 71% males) and followed up for a median duration of 228 days. Baseline and procedural data were similar in both age groups. A left-sided origin of PVCs was more frequently observed in the elderly patient group compared to younger patients (83% vs. 67%; p = .04). The median procedure time was significantly shorter in elderly patients (160 vs. 193 min; p = .02). The rates of both acute (86% vs. 92%; p = .32) and sustained success (70% vs. 71%; p = .90) were similar between groups. Complications rates (3.7%) did not differ between the two groups. In a large series of patients with a variety of underlying arrhythmia substrates, similar rates of acute procedural success, complications, and ventricular arrhythmia-free-survival were observed after CA of PVCs. Older age alone should not be a reason to withhold CA of PVCs.

Ablation of idiopathic premature ventricular contractions – exploring the electrophysiologist's toolbox in complex procedures

Ablation of idiopathic premature ventricular contractions – exploring the electrophysiologist's toolbox in complex procedures

Empiric catheter ablation of premature ventricular contractions when there is a >20% burden in an asymptomatic patient with normal left ventricular size and function-An argument for a conservative, do-less approach.

Premature ventricular contractions (PVCs) are common. Historically they have been considered benign in the setting of a normal heart, with long-term prognosis in asymptomatic healthy subjects with frequent PVCs showing a similar long-term prognosis to that of a healthy U.S. population, without an increased risk of death.1

Delayed radiofrequency ablation efficacy in slow pathway ablation: a case report.

BackgroundThe delayed effect of radiofrequency (RF) ablation was described in cases of accessory pathway and premature ventricular contraction ablation, as well as delayed atrioventricular (AV) block after slow pathway ablation.Case summaryWe report a case of a female patient with AV nodal re-entry tachycardia (AVNRT), in whom the first electrophysiology study ended with acute failure of slow pathway ablation, despite using long steerable sheath, both right and left-sided ablation with >15 min of RF energy application and repeatedly achieving junctional rhythm. Six weeks afterwards, during scheduled three-dimensional electroanatomical mapping procedure, there was no proof of dual AV nodal conduction nor could the tachycardia be induced. Also, the patient did not have palpitations between the two procedures nor during the 12-month follow-up period.DiscussionThis case illustrates that watchful waiting for delayed RF ablation efficacy in some cases of AVNRT ablation could be reasonable, in order to reduce the risk of complications associated with slow pathway ablation.

Successful radiofrequency ablation of para-left bundle branch premature ventricular contractions: Aimingat the breakout point to spare the conduction system

Background: The origin of the arrhythmia and its breakout point may be located apart. This has been described for arrhythmias originating within the His-Purkinje system. Case presentation: We report a case of a 70-year-old man with right bundle branch block and left anterior fascicular block with idiopathic nonsustained ventricular tachycardia originating in the septal left ventricular outflow close to the proximal left bundle branch. Ablation was successfully and safely performed away from the origin of the arrhythmia near the left anterior fascicle, at the breakout point. Arrhythmias from the conduction system may have different preferential exits and meticulous activation sequence mapping is the preferable strategy to select the ablation site.

Vitamin D as a Substitute of Catheter Ablation in a Paediatric Patient with High Burden Premature Ventricular Contractions: A Case Report

Catheter ablation is established as a treatment option for patients with high number Premature Ventricular Contractions (PVCs). However, complications can occur: cardiac tamponade, coronary artery injury or infectious endocarditis. Reversible causes such as hypocalcaemia, hypomagnesaemia and hypokalemia can be responsible for PVCs. Here, a case of nine years old boy, with vitamin D deficiency that presented high number PVCs which corrected using vitamin D dietary supplementation was described. A nine-year-old boy was hospitalised in the Cardiology Department for catheter ablation of PVCs. He presented short of breath during football matches and asthenia. Electrocardiography(ECG) and Holter ECG demonstrated high number PVCs with a morphology consistent of Right Ventricular Outflow Tract (RVOT) origin. Catheter ablation was postponed until Vitamin D came to normal values. Dietary supplementation was performed, together with Holter ECG monitoring. After vitamin D normalisation, PVC burden reduced significantly without the need of catheter ablation or anti-arrhythmic drugs. Catheter ablation and anti-arrhythmic drugs can be avoided in patients with frequent PVCs and vitamin D deficiency.