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JACC. Clinical Electrophysiology Dec 2017Fascicular ventricular arrhythmias represent a spectrum of ventricular tachycardias dependent on the specialized conduction system. Although they are more common in... (Review)
Review
Fascicular ventricular arrhythmias represent a spectrum of ventricular tachycardias dependent on the specialized conduction system. Although they are more common in structurally abnormal hearts, there is an increasing body of literature describing their role in normal hearts. In this review, the authors present data from both basic and clinical research that explore the current understanding of idiopathic fascicular ventricular arrhythmias. Evaluation of the cellular electrophysiology of the Purkinje cells shows clear evidence of enhanced automaticity and triggered activity as potential mechanisms of arrhythmias. Perhaps more importantly, heterogeneity in conduction system velocity and refractoriness of the left ventricular conduction system in animal models are in line with clinical descriptions of re-entrant fascicular arrhythmias in humans. Further advances in our understanding of the conduction system will help bridge the current gap between basic science and clinical fascicular arrhythmias.
Topics: Animals; Arrhythmias, Cardiac; Catheter Ablation; Electrocardiography; Heart Conduction System; Heart Ventricles; Humans; Models, Animal; Purkinje Fibers; Tachycardia, Ventricular
PubMed: 29759663
DOI: 10.1016/j.jacep.2017.07.011 -
Medicina (Kaunas, Lithuania) Apr 2023Pulsed field ablation (PFA) is a new ablative method for the therapy of arrhythmia. Recent preclinical and clinical studies have already demonstrated the feasibility and... (Review)
Review
Pulsed field ablation (PFA) is a new ablative method for the therapy of arrhythmia. Recent preclinical and clinical studies have already demonstrated the feasibility and safety of PFA for the treatment of atrial fibrillation (AF). However, the application of PFA may not be limited to the above fields. There are some data on the application of PFA on ventricular arrhythmias (VAs), such as ventricular fibrillation (VF) and ventricular tachycardia (VT). Further, a case report about PFA has been published recently, in which PFA was successfully applied to the ablation of premature ventricular contractions (PVCs) from the right ventricular outflow tract. Thus, we aimed to review recent research findings of PFA in ventricular ablation and evaluate the possibility of its application in VAs.
Topics: Humans; Treatment Outcome; Tachycardia, Ventricular; Ventricular Premature Complexes; Heart Ventricles; Atrial Fibrillation; Catheter Ablation
PubMed: 37109681
DOI: 10.3390/medicina59040723 -
JACC. Clinical Electrophysiology Apr 2019This study reports the use of a novel "Lumipoint" algorithm in ventricular tachycardia (VT) ablation.
OBJECTIVES
This study reports the use of a novel "Lumipoint" algorithm in ventricular tachycardia (VT) ablation.
BACKGROUND
Automatic mapping systems aid rapid acquisition of activation maps. However, they may annotate farfield rather than nearfield signal in low voltage areas, making maps difficult to interpret. The Lumipoint algorithm analyzes the complete electrogram tracing and therefore includes nearfield signals in its analysis.
METHODS
Twenty-two patients with ischemic cardiomyopathy and 5 with dilated cardiomyopathy underwent mapping using the ultra-high density Rhythmia system. Lumipoint algorithms were applied retrospectively.
RESULTS
In all left ventricular substrate maps, changing the window of interest to the post-QRS phase automatically identified late potentials. In 25 of 27 left ventricular VT activation maps, a minimum spatial window of interest correctly identified the VT isthmus as seen by the manually annotated map, entrainment, and response to ablation. In 6 maps, the algorithm identified the isthmus where the standard automatically annotated map did not.
CONCLUSIONS
The Lumipoint algorithm automatically highlights areas with electrograms having specific characteristics or timings. This can identify late and fractionated potentials and regions that exhibit discontinuous activation, as well as the isthmus of a VT circuit. These features may enhance human interpretation of the electrogram signals during a case, particularly where the circuit lies in partial scar with low amplitude nearfield signals and potentially allow a more targeted ablation strategy.
Topics: Aged; Algorithms; Catheter Ablation; Electrophysiologic Techniques, Cardiac; Female; Heart Ventricles; Humans; Male; Middle Aged; Retrospective Studies; Tachycardia, Ventricular
PubMed: 31000101
DOI: 10.1016/j.jacep.2019.01.016 -
Heart Rhythm Jul 2018Criteria for identification of anatomic ventricular tachycardia substrates in arrhythmogenic right ventricular cardiomyopathy (ARVC) on late gadolinium enhancement (LGE)...
Association of regional epicardial right ventricular electrogram voltage amplitude and late gadolinium enhancement distribution on cardiac magnetic resonance in patients with arrhythmogenic right ventricular cardiomyopathy: Implications for ventricular tachycardia ablation.
BACKGROUND
Criteria for identification of anatomic ventricular tachycardia substrates in arrhythmogenic right ventricular cardiomyopathy (ARVC) on late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) are unclear.
OBJECTIVE
The purpose of this study was to define (1) the association of regional right ventricular (RV) epicardial voltage amplitude with the distribution of LGE; and (2) appropriate image signal intensity (SI) thresholds for ventricular tachycardia substrate identification in ARVC.
METHODS
Preprocedural LGE-CMR and epicardial electrogram mapping were performed in 10 ARVC patients. The locations of epicardial electrogram map points, obtained during sinus rhythm with intrinsic conduction or RV pacing, were retrospectively registered to the corresponding LGE image regions. Standardized SI z-scores (standard deviation distance from the mean) were calculated for each 10-mm region surrounding map points.
RESULTS
In patient-clustered, generalized estimating equations models that included 3205 epicardial electroanatomic points and corresponding SI measures, bipolar (-1.43 mV/z-score; P <.001) and unipolar voltage amplitude (-1.22 mV/z-score; P <.001) were associated with regional SI z-scores. In contrast to the QRS-late potential (LP) interval (P = .362), the LP activation index, defined as electrogram duration divided by QRS-LP, was associated with regional SI z-scores (P <.001). SI z-score thresholds >0.05 (95% confidence interval -0.05 to 0.15) and <-0.16 (95% confidence interval -0.26 to 0.06) corresponded to bipolar voltage measures <0.5 and >1.0 mV, respectively.
CONCLUSION
Increased RV gadolinium uptake is associated with lower epicardial bipolar and unipolar electrogram voltage amplitude. Standardized LGE-CMR SI z-scores may augment preprocedural planning for identification of low-voltage zones and abnormal myocardium in ARVC.
Topics: Adolescent; Adult; Arrhythmogenic Right Ventricular Dysplasia; Catheter Ablation; Contrast Media; Epicardial Mapping; Female; Follow-Up Studies; Gadolinium DTPA; Heart Conduction System; Heart Rate; Heart Ventricles; Humans; Imaging, Three-Dimensional; Magnetic Resonance Imaging, Cine; Male; Middle Aged; Retrospective Studies; Tachycardia, Ventricular; Young Adult
PubMed: 29501666
DOI: 10.1016/j.hrthm.2018.02.030 -
PLoS Genetics Jul 2017Coordinated cardiomyocyte growth, differentiation, and morphogenesis are essential for heart formation. We demonstrate that the bHLH transcription factors Hand1 and...
Coordinated cardiomyocyte growth, differentiation, and morphogenesis are essential for heart formation. We demonstrate that the bHLH transcription factors Hand1 and Hand2 play critical regulatory roles for left ventricle (LV) cardiomyocyte proliferation and morphogenesis. Using an LV-specific Cre allele (Hand1LV-Cre), we ablate Hand1-lineage cardiomyocytes, revealing that DTA-mediated cardiomyocyte death results in a hypoplastic LV by E10.5. Once Hand1-linage cells are removed from the LV, and Hand1 expression is switched off, embryonic hearts recover by E16.5. In contrast, conditional LV loss-of-function of both Hand1 and Hand2 results in aberrant trabeculation and thickened compact zone myocardium resulting from enhanced proliferation and a breakdown of compact zone/trabecular/ventricular septal identity. Surviving Hand1;Hand2 mutants display diminished cardiac function that is rescued by concurrent ablation of Hand-null cardiomyocytes. Collectively, we conclude that, within a mixed cardiomyocyte population, removal of defective myocardium and replacement with healthy endogenous cardiomyocytes may provide an effective strategy for cardiac repair.
Topics: Animals; Basic Helix-Loop-Helix Transcription Factors; Cell Differentiation; Cell Lineage; Gene Expression Regulation, Developmental; Heart; Heart Ventricles; Humans; Mice; Mice, Knockout; Morphogenesis; Mutation; Myocytes, Cardiac
PubMed: 28732025
DOI: 10.1371/journal.pgen.1006922 -
Journal of the American College of... Sep 1998The purpose of this study was to determine if entrainment mapping techniques and predictors of successful ablation sites previously tested in coronary artery disease can...
OBJECTIVES
The purpose of this study was to determine if entrainment mapping techniques and predictors of successful ablation sites previously tested in coronary artery disease can be applied to ventricular tachycardia (VT) in arrhythmogenic right ventricular dysplasia (ARVD).
BACKGROUND
VT in ARVD has not been well characterized. Reentry circuits in areas of abnormal myocardium are the likely cause, but these circuits have not been well defined.
METHODS
Mapping of 19 VTs in 5 patients with ARVD was performed. At 58 sites pacing entrained VT and radiofrequency current (RF) was applied to assess acute termination of VT.
RESULTS
Sites classified as exits, central/proximal, inner loop, outer loop, remote bystander and adjacent bystander were identified by entrainment criteria. The reentrant circuit sites were clustered predominantly around the tricuspid annulus and in the right ventricular outflow tract (RVOT). RF ablation acutely terminated VT at 13 sites or 22% of the applications. Of the 19 VTs, eight were rendered noninducible and three were modified to a longer cycle length. In 2 patients ablation at a single site abolished two VTs.
CONCLUSION
VT in ARVD shows many of the characteristics of VT due to myocardial infarction. Entrainment mapping techniques can be used to characterize reentry circuits in ARVD. The use of entrainment mapping to guide ablation is feasible.
Topics: Adult; Aged; Arrhythmogenic Right Ventricular Dysplasia; Cardiac Pacing, Artificial; Catheter Ablation; Electrocardiography; Female; Heart Ventricles; Humans; Male; Middle Aged; Postoperative Complications; Tachycardia, Ventricular; Treatment Outcome
PubMed: 9741518
DOI: 10.1016/s0735-1097(98)00292-7 -
JACC. Clinical Electrophysiology Apr 2022This study sought to explore whether prolonged duration (PD) radiofrequency ablation (RFA) from adjacent endocardial locations can improve catheter ablation (CA)...
OBJECTIVES
This study sought to explore whether prolonged duration (PD) radiofrequency ablation (RFA) from adjacent endocardial locations can improve catheter ablation (CA) outcomes of left ventricular summit (LVS) ventricular arrhythmias (Vas).
BACKGROUND
CA of VAs originating from the LVS region can be challenging.
METHODS
Patients undergoing CA of LVS VAs from January 1, 2015, to December 31, 2019, were included. Standard RFA approach involved incremental power titration (20-45 W) over 60-120 seconds with irrigated tip catheter to achieve 10%-12% impedance drop. Prolonged duration RFA involved similar power titration; however, lesion application was extended beyond 120 seconds (maximum 5 minutes). Lesions were confined to lowest aspect of aortic cusps and/or subvalvular LV outflow tract region (≤0.5 cm from the valve). Procedural success was defined as suppression of VA ≥30 minutes postablation and clinical success as no arrhythmia symptoms on follow-up and >80% reduction of VA burden on postprocedure monitor.
RESULTS
This study included 102 patients (60±14 years old, 62% male): standard RFA in 80 and PD RFA in 38. Procedural success was achieved in 54 patients with standard and 32 patients with PD RFA (68% vs 84%; P = 0.05). Short-term clinical success was achieved in 48 patients (60%) with standard and 30 patients (79%) with PD RFA (P = 0.04). Two pericardial effusions occurred (1 in each group) and no steam pops were noted. Patients in whom standard RFA was successful were more likely to have R/S ratio >1 or absence of qS in lead I (odds ratio: 3.35; 95% CI: 1.20-9.35; P = 0.03).
CONCLUSIONS
Prolonged duration RFA from adjacent endocardial locations is a safe and effective technique for successfully targeting challenging LVS VAs that fail standard RFA.
Topics: Aged; Arrhythmias, Cardiac; Catheter Ablation; Endocardium; Female; Heart Ventricles; Humans; Male; Middle Aged; Treatment Outcome
PubMed: 35450601
DOI: 10.1016/j.jacep.2021.12.010 -
Journal of Interventional Cardiology 2023Ventricular extrasystoles (VESs) are common and often harmless in a healthy heart, but they can significantly affect the quality of life. If changes in lifestyle and...
BACKGROUND
Ventricular extrasystoles (VESs) are common and often harmless in a healthy heart, but they can significantly affect the quality of life. If changes in lifestyle and antiarrhythmic medication are not enough, invasive and often curative catheter ablation can be considered. Better understanding of the conformation of VESs with a 12-lead ECG, as well as their precise localization, have increased their treatment with catheter ablation. Our goal was to determine whether the anatomical site of VES had an effect on procedure success. We also analyzed the safety of the procedure and patient-related factors affecting the results.
MATERIALS AND METHODS
In this retrospective study, we analyzed the medical records of 63 consecutive patients with multiple idiopathic VESs treated by catheter ablation at Heart Hospital, Tampere University Hospital, during 2017 and 2018. Patients with structural heart disease were excluded. Ablation success was estimated with two endpoints, primary and follow-up success.
RESULTS
The majority of the patients received treatment on the right ventricular outflow tract (66.7%), others on the left ventricle (17.5%), or the aortic cusp (9.5%). The site of origin remained unknown in four procedures (6.3% of patients). Primary success was observed in 48 procedures (76.2%). During the follow-up period of three months, the procedure was successful in 70.3% of the cases. The anatomical site of VES had no significant effect on either primary or follow-up success. Those with a successful follow-up result had a lower body mass index (BMI = 26.4) than those who had an unsuccessful result (BMI = 28.7; =0.069); this did not reach statistical significance, potentially due to the small study population size. Complications were observed in three patients (4.5%). All of them were related to the catheter insertion site.
CONCLUSIONS
For a symptomatic patient, catheter ablation is an effective and often fully curative treatment. The success rate was similar regardless of the site of VESs. This suggests that catheter ablation should also be assessed early on for other cases besides classic right ventricular outflow tract VESs. A high BMI was the only factor associated with a poor procedure success rate. The procedure itself is safe, and adverse effects are rare. The radiation dose is also low partly due to the current magnetic navigation method.
Topics: Humans; Ventricular Premature Complexes; Retrospective Studies; Quality of Life; Heart Ventricles; Electrocardiography; Catheter Ablation; Tachycardia, Ventricular; Treatment Outcome
PubMed: 37928976
DOI: 10.1155/2023/5590422 -
JACC. Clinical Electrophysiology Oct 2020This study sought to address whether technological innovations such as contact force sensing (CFS) can improve acute and long-term ablation outcomes of left ventricular...
OBJECTIVES
This study sought to address whether technological innovations such as contact force sensing (CFS) can improve acute and long-term ablation outcomes of left ventricular papillary muscle (LV PAP) ventricular arrhythmias (VAs).
BACKGROUND
Catheter ablation of LV PAP VAs has been less efficacious than another focal VAs. It remains unclear whether technological innovations such as CFS can improve acute and long-term ablation outcomes of LV PAP VA.
METHODS
From January 2015 to December 2019, a total of 137 patients underwent LV PAP VA ablation. VA site of origin (SOO) was identified using activation and pace-mapping guided by intracardiac echocardiography. Radiofrequency energy (20 to 50 W for 60 to 90 s) was delivered by irrigated catheter with or without CFS. We defined acute success as complete suppression of targeted VA ≥30 min post ablation and clinical success as ≥80% VA burden reduction at outpatient follow-up.
RESULTS
VA manifested as premature ventricular complexes in 98 (71%), nonsustained ventricular tachycardia in 18 (13%), sustained ventricular tachycardia in 12 (9%) and premature ventricular complexes induced ventricular fibrillation in 9 (7%). VA SOO was anterolateral PAP in 51 (37%), posteromedial PAP in 73 (53%), and both PAPs in 13 (10%). VAs were targeted using CFS in 97 (71%) and non-CFS in 40 (29%). After a single procedure, acute success was achieved in 130 (95%) and clinical success was achieved in 112 (82%); neither was impacted by VA SOO and/or CFS. Complications occurred in 5 patients (3.6%).
CONCLUSION
Independent of CFS technology, intracardiac echocardiography-guided catheter ablation is highly efficacious and may be considered as first-line therapy in the management of LV PAP VA.
Topics: Catheter Ablation; Heart Ventricles; Humans; Papillary Muscles; Tachycardia, Ventricular; Ventricular Premature Complexes
PubMed: 33121667
DOI: 10.1016/j.jacep.2020.06.026 -
Journal of Cardiovascular... Jul 2018
Topics: Heart Ventricles; Humans; Tachycardia, Ventricular
PubMed: 29771455
DOI: 10.1111/jce.13633