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Heart Rhythm Nov 2023Cardioneuroablation (CNA) is an attractive treatment of vasovagal syncope. Its long-term efficacy and safety remain unknown.
BACKGROUND
Cardioneuroablation (CNA) is an attractive treatment of vasovagal syncope. Its long-term efficacy and safety remain unknown.
OBJECTIVE
The purpose of this study was to develop a chronic porcine model of CNA to examine the susceptibility to ventricular tachyarrhythmia (ventricular tachycardia/ventricular fibrillation [VT/VF]) and cardiac autonomic function after CNA.
METHODS
A percutaneous CNA model was developed by ablation of left- and right-sided ganglionated plexi (n = 5), confirmed by histology. Reproducible bilateral vagal denervation was confirmed after CNA by extracardiac vagal nerve stimulation (VNS) and histology. Chronic studies included 16 pigs randomized to CNA (n = 8) and sham ablation (n = 8, Control). After 6 weeks, animals underwent hemodynamic studies, assessment of cardiac sympathetic and parasympathetic function using sympathetic chain stimulation and direct VNS, respectively, and proarrhythmic potential after left anterior descending (LAD) coronary artery ligation.
RESULTS
After CNA, extracardiac VNS responses remained abolished for 6 weeks despite ganglia remaining in ablated ganglionated plexi. In the CNA group, direct VNS resulted in paradoxical increases in blood pressure, but not in sham-ablated animals (CNA group vs sham group: 8.36% ± 7.0% vs -4.83% ± 8.7%, respectively; P = .009). Left sympathetic chain stimulation (8 Hz) induced significant corrected QT interval prolongation in the CNA group vs the sham group (11.23% ± 4.0% vs 1.49% ± 4.0%, respectively; P < .001). VT/VF after LAD ligation was more prevalent and occurred earlier in the CNA group than in the control group (61.44 ± 73.7 seconds vs 245.11 ± 104.0 seconds, respectively; P = .002).
CONCLUSION
Cardiac vagal denervation is maintained long-term after CNA in a porcine model. However, chronic CNA was associated with cardiovascular dysreflexia, diminished cardioprotective effects of cardiac vagal tone, and increased susceptibility to VT/VF in ischemia. These potential long-term negative effects of CNA suggest the need for rigorous clinical studies on CNA.
Topics: Animals; Autonomic Dysreflexia; Heart; Heart Ventricles; Ischemia; Swine; Tachycardia, Ventricular; Ventricular Fibrillation
PubMed: 37562487
DOI: 10.1016/j.hrthm.2023.08.001 -
JACC. Clinical Electrophysiology Sep 2023Three cases of ventricular tachycardia ablation with pulsed-field ablation technology performed at 2 separate centers are reported, highlighting the advantages and... (Review)
Review
Three cases of ventricular tachycardia ablation with pulsed-field ablation technology performed at 2 separate centers are reported, highlighting the advantages and disadvantages of this tool inside the ventricle: its dependence on proximity rather than contact makes it useful in sites with poor stability, while the speed of application and large scope of action provided by commercially available catheters could help with ablating large diseased areas of endocardium in a fast and hemodynamically well-tolerated fashion. However, lesion depth could be insufficient for guaranteeing efficacy in preventing ventricular tachycardias originating at an epicardial site, even in the right ventricle.
Topics: Humans; Heart Ventricles; Electrocardiography; Tachycardia, Ventricular; Catheter Ablation; Endocardium
PubMed: 37227358
DOI: 10.1016/j.jacep.2023.03.024 -
Cardiac Electrophysiology Clinics Mar 2023Most idiopathic ventricular arrhythmias (VAs) originate from the outflow tract (OT) region and can be targeted with ablation either from the endocardial aspect of the... (Review)
Review
Most idiopathic ventricular arrhythmias (VAs) originate from the outflow tract (OT) region and can be targeted with ablation either from the endocardial aspect of the right and left ventricular outflow tracts or from the aortic sinuses of Valsalva. It is important to exclude scar in patients with OT VAs. In some patients, the site of origin may be intramural. Ablation of intramural OT VAs can be challenging to map and ablate due to deep intramural sites of origin. The coronary venous branches may permit mapping and ablation of intramural OT VAs.
Topics: Humans; Tachycardia, Ventricular; Electrocardiography; Treatment Outcome; Catheter Ablation; Arrhythmias, Cardiac; Heart Ventricles
PubMed: 36774136
DOI: 10.1016/j.ccep.2022.04.006 -
Cardiac Electrophysiology Clinics Mar 2023The left ventricular summit (LVS) is the area in the highest portion of the left ventricular epicardium, bounded by the left coronary arteries and the coronary venous... (Review)
Review
The left ventricular summit (LVS) is the area in the highest portion of the left ventricular epicardium, bounded by the left coronary arteries and the coronary venous circulation, and can be surrounded by thick epicardial fat that may preclude epicardial ablation. Ablation of LVS ventricular arrhythmias (VA) can be achieved from adjacent structures with good success rates. The long-term freedom from LVS VA recurrence remains variable. This article reviews the spatial and anatomic relationship of the structures surrounding the LVS, which provide vantage points for ablation, and the acute and long-term outcomes of different ablation approaches in LVS VA ablation.
Topics: Humans; Tachycardia, Ventricular; Treatment Outcome; Heart Ventricles; Arrhythmias, Cardiac; Catheter Ablation; Electrocardiography
PubMed: 36774140
DOI: 10.1016/j.ccep.2022.07.003 -
Cardiac Electrophysiology Clinics Mar 2023The left ventricular summit (LVS) is the highest point of the left ventricular epicardium, and ventricular arrhythmias originating from this area accounts for 10% to 15%... (Review)
Review
The left ventricular summit (LVS) is the highest point of the left ventricular epicardium, and ventricular arrhythmias originating from this area accounts for 10% to 15% of idiopathic outflow tract ventricular arrhythmias. Direct epicardial ablation of outflow tract ventricular arrhythmias arising from the LVS is successful only in a minority of patients because of close proximity to the coronary artery or thick epicardial fat. Therefore, alternative strategies should be prioritized before performing epicardial approach. When performed, electrocardiogram characteristics suggestive of the site of origin to be the accessible area within the LVS needs be evaluated to avoid ineffective epicardial approach.
Topics: Humans; Tachycardia, Ventricular; Electrocardiography; Treatment Outcome; Heart Ventricles; Arrhythmias, Cardiac; Catheter Ablation
PubMed: 36774133
DOI: 10.1016/j.ccep.2022.07.002 -
Pacing and Clinical Electrophysiology :... Jan 2020Recurrence rates after catheter radiofrequency ablation (RFA) for arrhythmias arising from deep myocardial substrates can exceed 40%. Failure of RFA is in part due to...
BACKGROUND
Recurrence rates after catheter radiofrequency ablation (RFA) for arrhythmias arising from deep myocardial substrates can exceed 40%. Failure of RFA is in part due to the inability of widely used unipolar ablation (UA) to create transmural lesions capable of disrupting the critical components of the arrhythmia circuit. A radiofrequency generator was custom-made to deliver bipolar ablation (BA) to test the hypothesis that BA is more effective compared to UA in achieving transmurality and to determine the optimal configuration for ventricular BA.
METHODS
Sequential UA and BA were created in porcine ventricular septal and free wall preparations using irrigated, contact-force sensing ablation catheters, orientated perpendicularly to the myocardium. Return catheters, durations of ablation, irrigating fluids, and power settings were varied to determine the optimal configuration for BA. Lesion characteristics, transmurality, and occurrence of steam pops were analyzed.
RESULTS
In both ventricular septal and free wall models, BA resulted in significantly more transmural lesions while causing less steam pops (P < .01). BA lesions were deeper, narrower but larger in volume. Use of 8 mm ground catheters in the epicardium resulted in overheating during BA with temperatures exceeding 95°C, limiting power delivery. Increasing duration and powers of BA resulted in progressively larger lesions and increased transmurality (all P < .01), and 0.45% saline as the irrigation did not enhance BA.
CONCLUSION
BA created larger lesions with increased chances of transmurality but at lower risks of steam pops. Use of an irrigated catheter as the return electrode and 30 W of BA delivered over 120 seconds provides the optimal balance between creating deep, transmural lesions and avoiding steam pops.
Topics: Animals; Cardiac Catheters; Catheter Ablation; Electrodes; Equipment Design; Heart Ventricles; In Vitro Techniques; Models, Animal; Swine; Therapeutic Irrigation
PubMed: 31721241
DOI: 10.1111/pace.13844 -
Journal of Cardiovascular... Mar 2022Ethanol ablation (EA) is an alternative option for subjects with ventricular arrhythmias (VAs) refractory to conventional medical and ablative treatment. However, data... (Meta-Analysis)
Meta-Analysis Review
INTRODUCTION
Ethanol ablation (EA) is an alternative option for subjects with ventricular arrhythmias (VAs) refractory to conventional medical and ablative treatment. However, data on the efficacy and safety of EA remain sparse.
METHODS
A systematic literature search was conducted. The primary outcomes were 1) freedom from the targeted VA and 2) freedom from any VAs post-EA. Additional safety outcomes were also analyzed.
RESULTS
Ten studies were selected accounting for a population of 174 patients (62.3 ± 12.5 years, 94% male) undergoing 185 procedures. The overall acute success rate of EA was 72.4% (confidence interval [CI ]: 65.6-78.4). After a mean follow-up of 11.3 ± 5.5 months, the incidence of relapse of the targeted VA was 24.4% (CI : 17.1-32.8), while any VAs post-EA occurred in 41.3% (CI : 33.7-49.1). The overall incidence of procedural complications was 14.1% (CI : 9.8-19.8), with pericardial complications and complete atrioventricular block being the most frequent. An anterograde transarterial approach was associated with a higher rate of VA recurrences and complications compared to a retrograde transvenous route; however, differences in the baseline population characteristics and in the targeted ventricular areas should be accounted.
CONCLUSION
EA is a valuable therapeutic option for VAs refractory to conventional treatment and can result in 1-year freedom from VA recurrence in 60%-75% of the patients. However, anatomical or technical challenges preclude acute success in almost 30% of the candidates and the rate of complication is not insignificant, highlighting the importance of well-informed patient selection. The certainty of the evidence is low, and further research is necessary.
Topics: Arrhythmias, Cardiac; Catheter Ablation; Ethanol; Female; Heart Ventricles; Humans; Male; Retrospective Studies; Tachycardia, Ventricular; Treatment Outcome
PubMed: 34921464
DOI: 10.1111/jce.15336 -
Pacing and Clinical Electrophysiology :... Feb 2024The left ventricular summit (LVS) refers to the highest portion of the left ventricular outflow tract (LVOT). It is an epicardially delimited triangular area by the left... (Review)
Review
The left ventricular summit (LVS) refers to the highest portion of the left ventricular outflow tract (LVOT). It is an epicardially delimited triangular area by the left coronary arteries and the coronary venous circulation. Its deep myocardium correlates closely with the left coronary cusp, aortic-mitral continuity, and right ventricular outflow tract (RVOT), complicating the anatomical relationship. Ventricular arrhythmias (VAs) originating from this area are common, accounting for 14.5% of all VAs origin from left ventricle. Specific electrocardiogram (ECG) characteristics may assist in locating LVS-VAs pre-procedure and facilitate procedure planning. However, catheter ablation of LVS-VAs remains challenging because of anatomical constraints. This paper reviews the recent understanding of LVS anatomy, concludes ECG characteristics, and summarizes current mapping and ablation methods for LVS-VAs.
Topics: Humans; Heart Ventricles; Tachycardia, Ventricular; Arrhythmias, Cardiac; Aorta; Myocardium; Catheter Ablation; Electrocardiography; Treatment Outcome
PubMed: 38291856
DOI: 10.1111/pace.14932 -
JACC. Clinical Electrophysiology Dec 2022
Topics: Humans; Papillary Muscles; Heart Ventricles; Mitral Valve Insufficiency
PubMed: 36543497
DOI: 10.1016/j.jacep.2022.08.030 -
JACC. Clinical Electrophysiology Jan 2023The characteristics of patients with post-myocardial infarction (PMI) ventricular tachycardia (VT) who require right ventricular (RV) ablation are underreported.
BACKGROUND
The characteristics of patients with post-myocardial infarction (PMI) ventricular tachycardia (VT) who require right ventricular (RV) ablation are underreported.
OBJECTIVES
The aims of this study were to examine the characteristics and outcomes of patients undergoing PMI VT ablation who have target sites in the right ventricle and to compare patient and VT characteristics between patients with free wall vs septal RV target sites.
METHODS
Consecutive patients undergoing ablation for PMI VT with target sites located within the right ventricle were included. Patients were stratified on the basis of the presence of free wall vs septal RV target sites.
RESULTS
Among 277 consecutive patient undergoing PMI VT ablation, 30 (11%) had RV target sites (mean age 68.71 ± 9.5 years, 29 men [97%], mean left ventricular ejection fraction [LVEF] 28.7% ± 16.7%). Twenty patients had only septal VTs, and 10 patients had only free wall VTs. Fifty-seven VTs with RV targets (1.9 ± 1.4 per patient, mean cycle length 338 ± 90 ms, 53 left bundle branch, 36 superior axis) were induced. Patients with RV free wall VTs had greater rates of RV dysfunction (80% vs 30%; P = 0.023) but had greater LVEFs (38.3% ± 21.06% vs 23.9% ± 11.93%; P = 0.02). Over a mean follow-up period of 3.4 ± 3.2 years, patients with RV septal target sites had worse survival free of VT, transplantation, or left ventricular assist device placement after ablation (log-rank P < 0.05).
CONCLUSIONS
The arrhythmogenic substrate in PMI patients often involves the right ventricle, including the septum and free wall. The presence of RV dysfunction and greater LVEF were associated with the presence of RV free wall target sites. Patients with only RV septal target sites had worse postablation outcomes.
Topics: Male; Humans; Middle Aged; Aged; Heart Ventricles; Stroke Volume; Ventricular Function, Left; Tachycardia, Ventricular; Myocardial Infarction; Catheter Ablation
PubMed: 36697197
DOI: 10.1016/j.jacep.2022.08.034