Overview

Ventricular tachycardia (VT) is an abnormal and dangerous heart rhythm affecting the lower chambers of the heart (the ventricles). Patients with structural heart disease caused by previous heart attacks are at an increased risk of developing VT. Current guidelines recommend that patients who develop this abnormal heart rhythm are considered for invasive catheter ablation (ICA). This is an invasive procedure where specialised catheters and a 3D electro anatomical mapping (EAM) system are used to identify the region of the heart responsible for the VT, which is then treated by tissue heating or freezing (ablation). Although significant improvements have been made in both mapping and ablation technologies, these procedures remain technically challenging and time consuming.

View into ventricular onset (VIVO, Catheter Precision) is a non-invasive, mapping system already being used within the NHS. It uses images from previous heart scans, a picture of the patient's chest (taken at the start of the procedure) and a 12-lead electrocardiogram (ECG) tracing, to locate where the VT is coming from. The VIVO map can therefore highlight the likely region of interest for ICA prior to invasive EAM.

This study will be a prospective, multi-centre, two-arm, non-blinded, randomised controlled trial (RCT). Patients will be evenly randomised (50:50) into a standard VT ablation group and a VIVO guided ablation group. In the VIVO guided ablation group, invasive EAM will be restricted to the region of interest identified using the VIVO map, rather than whole chamber mapping required for standard ablation. The primary objective will be to determine if the VIVO non-invasive mapping system reduces procedure duration and therefore improves workflow efficiency. Secondary objectives will assess the procedural success, safety and patient perceived health benefits of a VIVO guided ablation versus standard ablation.

Eligibility

Inclusion Criteria:

• ≥18 years old
• Patient with the following:
  • Evidence of post-myocardial infarction\* structural heart disease.
  • Cardiac CT and/or cardiac MRI scan performed within 6 months.
  • ICD/CRTD implantation.
  • Device therapy for VT: at least 1 appropriate ICD shock or 3 ATP episodes within a 6-month period.
• Suitable candidate for VT ablation as per NHS standard of care.
• Patient agrees to comply with study procedures and be available for routine follow up visits for at least 6 months after enrolment.

Exclusion Criteria:

• Lacks capacity to provide informed consent.
• Presence of intramural thrombus, tumour or abnormality that precludes vascular access, catheter introduction or manipulations.
• Coagulopathy, bleeding diathesis or suspected pro-coagulant state.
• Sepsis, active systemic infection or fever (\>100.5 F/38 C) within a week prior to the ablation procedure.
• Renal failure requiring dialysis or renal compromise that in the investigator's judgement would increase risk to the patient or deem the patient inappropriate to participate in the study.
• Known allergies or intolerance to AADs to be used to treat PVCs.
• Known allergy for contrast.
• Female patients who are pregnant or breast feeding.
• Enrolment in a concurrent interventional clinical study that in the judgement of the investigator would increase risk to the patient or deem them inappropriate to participate in this study.
• Other conditions that may prevent patients from adhering to the study protocol, in the opinion of the investigator.