Catheter Ablation Versus Anti-arrhythmic Drugs for Ventricular Tachycardia

Summary

Sudden cardiac death (SCD) due to recurrent ventricular tachycardia (VT) is an important clinical sequela in patients with structural heart disease. VT generally occurs as a result of electrical re-entry in the presence of arrhythmogenic substrate (scar). Scar tissue forms due to an ischemic cardiomyopathy (ICM) from prior coronary obstructive disease or a non-ischemic cardiomyopathy (NICM) from an inflammatory or genetic disease.

AADs can reduce VT recurrence, but have significant limitations in treatment of VT. For example, amiodarone has high rates of side effects/toxicities and a finite effective usage before recurrence. ICDs prevent cardiac arrest and sudden death from VT, but do not stop VT occurring. Recurrent VT and ICD therapies decrease QOL, increase hospital visits, mortality, morbidity and risk of death. Improvement in techniques for mapping and ablation of VT have made CA an alternative.

Currently, there is limited evidence to guide clinicians either toward AAD therapy or CA in patients with NICM. This data shows significant benefit of CA over medical therapy in terms of VT free survival, survival free of VT storm and VT burden. Observational studies suggest that CA is effective in eliminating VT in NICM patients who have failed AADs, resulting in reduction of VT burden and AAD use over long term follow up. Furthermore, there is limited data on the efficacy of CA in early ICM with VT, or advanced ICM with VT. RCT data is almost exclusively on patients with modest ICM with VT, and this is not representative of the real-world scenario of patients with structural heart disease presenting with VT.

Therefore the primary objective is to determine in all patients with structural heart disease and spontaneous or inducible VT, if catheter ablation compared to standard medical therapy with anti-arrhythmic drugs results in a reduction of a composite endpoint of recurrent VT, VT storm and death at a median follow up of 18 months.

Conditions

• Heart Disease Structural Disorder
• Ventricular Tachycardia
• Cardiomyopathy, Dilated
• Sarcoidosis
• Cardiomyopathy, Hypertrophic
• Cardiomyopathy Ischemic
• Cardiomyopathy, Familial
• Arrhythmogenic Right Ventricular Cardiomyopathy 1
• Arrhythmogenic Left Ventricular Cardiomyopathy

Interventions

PROCEDURE

Ablation

Catheter ablation (CA) will be performed in the standard fashion (described in international guidelines for the Management of Patients with Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death from the AHA/ACC/HRS and the expert consensus statement on Catheter Ablation of Ventricular Arrhythmias from HRS/EHRA/APHRS/LAHRS). CA will be performed under conscious sedation or GA by an Electrophysiologist trained in cardiac arrhythmia ablation. CA will be guided by a combination of mapping techniques (standard practice), and described in guidelines for CA for VT. Mapping techniques will include pace, entrainment, activation, and electro-anatomic substrate mapping, where haemodynamically tolerated. Expected procedure duration is 3-6hrs. Post-CA, AAD is stopped if patient was drug naïve pre-randomisation. The baseline type/dose of AAD pre-randomisation is continued if the patient was on an AAD pre-randomisation. Repeat ablations are permitted within 30-days post-randomisation.

DRUG

Anti-arrhythmic Drugs (AADs)

Standard care usually encompasses patients who have not previously had AADs, being commenced on sotalol 80mg twice/day. Lower doses may be initiated by treating doctor, as clinically indicated. If there is contraindication to sotalol, another beta-blocker may be initiated using standard doses. Clinicians may consider alternative AADs if there is contraindication to beta-blockers. Doses would be up titrated to the maximal tolerated amount. For patients already on an AAD, amiodarone would usually be added, as per VANISH trial. They will receive a loading dose 400mg twice/day for 2 weeks, followed by 400mg/day for 4 weeks and 200mg/day thereafter. Patients who have "failed" amiodarone dose \<300mg/day will receive a repeat loading dose of 400mg twice/day for 2 weeks, followed by 400mg/day for 1 week, and 300mg/day thereafter. If the treating doctor decides to do a CA for VT, the occurrence and timepoint of cross-over will be recorded. Cross-over is estimated to be \<2% (VANISH trial).

Sponsors & Collaborators

• Western Sydney Local Health District

  lead OTHER

Principal Investigators

• Saurabh Kumar, MBBS, PhD · Western Sydney Local Health District

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

SINGLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2020-07-08

Primary Completion

2026-06-30

Completion

2026-06-30

Countries

• Australia

Study Locations