Ventricular Catheter Ablation Study (VCAS) — VCAS  

Ventricular Tachycardia Clinical Trial

Official title: A Pre-Market, First-In-Human, Pilot, Interventional, Clinical Investigation to Evaluate Safety and Feasibility of the FieldForce™ Ablation System in Symptomatic Patients With Ventricular Arrhythmia

Status Not yet recruiting

Clinical Trial Summary

This is a prospective safety and feasibility study to evaluate the safety of the FieldForce™ Ablation system in patients with ventricular arrhythmia divided into two groups: VT (VCAS-I) and frequent premature ventricular complex (VCAS-II).

Clinical Trial Description

Summary: Ventricular arrythmias are common but often undertreated. The most effective pharmacologic management and implantable devices are used to treat deadly arrythmias like ventricular tachycardia (VT) and ventricular fibrillation (VF). However, the efficacy of antiarrhythmic drugs (AADs) has been proven to be low, and implantable cardioverter defibrillators (ICDs) treat VT but do not prevent it. Prospective trials demonstrate that VT ablation is by far the most effective therapy for ventricular tachycardia and in some cases it is curative. Despite overwhelming evidence that catheter ablation is superior, there are many technical barriers that prevent widespread application of this therapy. Furthermore, non-fatal ventricular arrythmias such as premature ventricular contractions (PVCs) are treatable by catheter ablation. The technical challenges facing VT and PVC ablations are similar as current technologies are optimized to treat atrial arrythmias often at the expense of performance in the ventricle. The European Heart Rhythm Association (EHRA), Heart Rhythm Society (HRS), and Asia Pacific Heart Rhythm Society (APHRS) Expert Consensus on Ventricular Arrhythmias recommends catheter ablation for symptomatic ventricular arrythmias both lethal and non-lethal such as PVCs refractory to medical management. First-line therapy for patients with VT/VF or severely impaired systolic function at risk of sudden death, consists of implantable cardioverter defibrillator (ICD) and/or antiarrhythmic drug therapy. However, ICDs do not prevent recurrent VT episodes, which may result in device tachy therapy including shocks. Antiarrhythmic drugs can be effective in preventing recurrent VT in a minority of patients reducing appropriate ICD shocks but are associated with significant long-term side effects and organ toxicities. Catheter ablation is an accepted first-line therapy for idiopathic VT which makes up a minority of clinical cases. Likewise, first line therapy for PVCs is pharmacologic. However, studies have shown that catheter ablation is 70.2% more effective (based on 1 year recurrence rate of 19.4% in RF ablation group versus 88.6% in antiarrhythmic therapy group) for treatment of PVCs. Minimally invasive catheter-based procedures are currently considered the most effective therapy available for VT but there are significant barriers to widespread application [8]. The challenges come from some practical considerations. The traditional approach for VT ablation implies the recognition of the origin and/or propagation of the myocardial signal during arrhythmia which is normally investigated through mappings done using an intracardiac mapping catheter. Catheter ablation is normally used with or without ICD implantation as a secondary prevention when AADs are either ineffective or not desirable. The recurrence rates of Ventricular Tachycardia (VT) RF ablation can vary widely and are about 12-47%. The authors point out factors that contribute to RF ablation treatment failure and the risk of high recurrence rates including inadequate lesion size and inability to create a transmural lesion in the ventricles. Strategies such as bipolar RF ablation have been studied where two separate catheters are positioned to deliver the energy between them that can increase the treatment depth. Even though bipolar ablation in the ventricles has shown the possibility of creating larger lesions compared to unipolar ablation, still it does not guarantee transmurality. The average transmurality using unipolar and bipolar RF in the ventricular tissue is 11% and 54%. Steam cavitation effect, which is also called steam pop, is a major complication that can lead to cardiac tamponade and/or VT. Based on the same review paper, steam pop occurred in 26% and 6% of the RF ablation procedures using unipolar and bipolar settings respectively. There are two main factors that contribute to the challenges facing RF ablation in the ventricle: first being the physics of thermodynamics and second being mechanical design of the delivery systems. Heat transfer physics are recognized to be extremely complex and difficult to predict in a beating heart. In order to achieve good lesions with RF ablation catheter stability and contact force are required. The complex anatomic geometry of the ventricle, which is deeply trabeculated, interferes with our ability to ablate tissue that is not a part of the compact ventricle myocardium leaving bridges of functional muscle intact over the target site. Stability is incredibly difficult to achieve since some parts of the ventricle move more than a centimeter during each cardiac cycle, furthermore the blood flow in the chamber works to cool the muscle counteracting effective heat transfer. The design considerations for catheter ablation are influenced by anatomic constraints. In order to perform catheter ablation almost all tools use femoral vascular access. Given that 90% of all catheter ablations procedures are done in the atria, it is no surprise that handling characteristics of these tools have been optimized to deliver therapy in the atria. Therefore, the current tools do not perform well in the ventricles interfering with our ability to deliver the ablation energy effectively. Although the mechanical challenges of the delivery system can be overcome, there has not been a lot of incentive to build tools specifically for ventricular arrythmias. In summary, these factors might explain why the ventricular RF ablation procedures are time consuming (3 to 7 hours). Despite the need for ablations in numerous patients, limited physicians can overcome the challenges of RF ablation in the ventricles which limits the number of total ablations done universally. Pulsed field ablation (PFA) is a new ablation method for the therapy of arrhythmias. PFA is considered as a non-thermal and low-energy method of ablation. This technique is characterized by pulse trains of short-duration and high-voltage electrical impulses that result in electric field-mediated tissue injury. The very strong electric fields put strain on cellular compartmentalization. These changes can be reversible, and cells can recover with no consequences; however, if compartmentalization is disrupted for an extended period of time, it results in metabolic injury and cell death. This mechanism is also known as electroporation. Different cell types are sensitive to these types of insults leading to tissue selectivity in the heart. Clinical studies have already demonstrated the feasibility and safety of PFA for the treatment of atrial fibrillation. However, there is less data on the application of PFA for VT. In this context, the FieldForce™ Ablation system utilizes an innovative electrode technology, designed to reduce the total ablation time, improved tolerability, minimize the transferred energy by about 20-25 times compared to RF, increase safety, eliminate the chance of steam pop and increase efficacy for focal deflectable catheters used for the treatment of ventricular arrythmias. Therefore, this Pre-Market, First-In-Human, Pilot, Interventional, Clinical Investigation aims to evaluate Safety and Feasibility of the FieldForce™ Ablation system in patients with ventricular tachycardia divided into two groups: ventricular tachycardia (VCAS-I) and unifocal premature ventricular complex (VCAS-II). ;

Related Conditions & MeSH terms

• Arrhythmias, Cardiac
• Premature Birth
• PVC - Premature Ventricular Complex
• Tachycardia
• Tachycardia, Ventricular
• Ventricular Arrythmia
• Ventricular Premature Complexes
• Ventricular Tachyarrhythmia
• Ventricular Tachycardia

• NCT number: NCT06203262
• Study type: Interventional
• Source: Field Medical
• Contact: Steven R Mickelsen, MD
• Phone: 319 333-8236
• Email: mickelsen@fieldmedicalinc.com
• Status: Not yet recruiting
• Phase: Phase 1/Phase 2
• Start date: March 1, 2024
• Completion date: June 1, 2025