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Anti-arrhythmic Medication v. MRI-Merge Ablation in the Treatment of Ventricular Tachycardia

The recruitment status of this study is unknown. The completion date has passed and the status has not been verified in more than two years.
Verified April 2012 by Johns Hopkins University.
Recruitment status was:  Not yet recruiting
Information provided by (Responsible Party):
Charles Henrikson, MD - Cardiology/Medicine, Johns Hopkins University Identifier:
First received: July 21, 2008
Last updated: April 26, 2012
Last verified: April 2012

Ventricular tachycardia (VT) is a morbid arrhythmia responsible for many sudden deaths and ICD shocks. Despite much progress in the treatment of arrhythmia, VT remains a therapeutic challenge. Most patients with VT have an implantable cardioverter defibrillator (ICD) for secondary prevention of sudden cardiac death, however, an ICD merely treats VT, it does not prevent VT. In patients with recurrent VT and ICD shocks, two strategies are available to decrease the burden of VT. The first is antiarrhythmic drugs, and the second is VT ablation. The aim of this study is to compare the efficacy of antiarrhythmic drugs and VT ablation guided by MRI. VT can sometimes be suppressed with antiarrhythmic medications, however, these are often ineffective, and carry a high burden of side effects. Many forms of VT can be cured by selective destruction of critical electrical pathways with catheter ablation. A major limitation in the ablation of VT, however, is the time required to localize scar tissue and important pathways for targeting of lesions. Magnetic resonance imaging can now obtain reliable images of scar location within the ventricles. Recent advances in electroanatomical mapping systems allow operators to import pre-acquired images into the mapping system. The aim of this study is to examine the feasibility of importing historic MRI scar maps of the ventricles into the electroanatomical system and using such images to guide catheter ablation, as compared to antiarrhythmic drug suppression of VT. We suspect that MRI guidance will be especially useful in patients with "unstable" VT, i.e. VT that causes an abrupt drop in blood pressure, and thus cannot be maintained in the EP lab for mapping and entrainment purposes. Patients referred for VT ablation have ICDs. Through previously completed animal work (Circulation 2004; 110(5): 475-82) and a human trial (2006 Sep 19;114(12):1277-84) we have demonstrated the safety of MRI in the setting of pacemakers and implantable defibrillators using appropriate precautions. Through careful device programming and using MRI sequences with limited energy exposure (specific absorption rate < 2 W/kg) we will study the pre procedural myocardial anatomy of patients enrolled into this study.

The primary endpoint will be lack of VT documented by implantable defibrillator (when present) interrogation or Holter monitoring 6 months post ablation. The secondary endpoints will be comparison of inducible arrhythmia at the end of the procedure, procedure time, comparison of endocardial voltage mapping to scar on delayed enhancement MRI images, and complications in each study arm.

Condition Intervention
Ventricular Tachycardia
Procedure: MRI guided VT ablation
Drug: Increased dose of amiodarone

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Open Label
Primary Purpose: Treatment
Official Title: Anti-arrhythmic Medication v. MRI-Merge Ablation in the Treatment of Ventricular Tachycardia

Resource links provided by NLM:

Further study details as provided by Johns Hopkins University:

Primary Outcome Measures:
  • Freedom from ventricular tachycardia documented by implantable defibrillator cardioverter 6 months post ablation. [ Time Frame: 6 months ]

Secondary Outcome Measures:
  • inducible arrhythmia at the end of the procedure, [ Time Frame: During procedure ]
  • Procedure time [ Time Frame: During procedure ]
  • Comparison of endocardial voltage mapping to scar on delayed enhancement MRI images [ Time Frame: During procedure ]
  • Complications of the procedure [ Time Frame: 30 days following procedure ]

Estimated Enrollment: 70
Study Start Date: June 2012
Estimated Study Completion Date: August 2012
Estimated Primary Completion Date: August 2012 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: 1
Magnetic resonance imaging (MRI)-guided ablation of ventricular tachycardia.
Procedure: MRI guided VT ablation
Magnetic resonance imaging (MRI)-guided ablation of ventricular tachycardia (VT)
Active Comparator: 2
Anti-arrhythmic group.
Drug: Increased dose of amiodarone

Increase the dose of amiodarone according to the following scheme:

current dose -> new dose 100 QD -> 200 QD; 200 QD -> 400 QD; 300 QD -> 600 QD; 400 QD -> 600 QD


Ages Eligible for Study:   18 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No


  • Current treatment with amiodarone
  • Ischemic or non-ischemic cardiomyopathy
  • Monomorphic ventricular tachycardia at any cycle length, with > 1 occurrence of the same cycle length and morphology, at least one episode needs to be of sufficient duration to result in a shock.
  • No contraindication to up titration of meds or to VT RFA


  • Primary antiarrhythmic medication other than amiodarone
  • Amiodarone at dose of 600 mg daily or higher
  • Polymorphic VT as culprit rhythm
  • History of metal exposure (welding)
  • Pregnant women
  • Recent myocardial infarction
  • Planned coronary revascularization
  • Implantable cardiac devices not previously tested for safety in the setting of MRI
  • GFR < 30 ml/min
  Contacts and Locations
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Please refer to this study by its identifier: NCT00721032

Contact: Charles A Henrikson, MD 410 955 2412
Contact: Saman Nazarian, MD 410 614 2751

Sponsors and Collaborators
Johns Hopkins University
  More Information

Responsible Party: Charles Henrikson, MD - Cardiology/Medicine, Assistant Professor of Medicine, Johns Hopkins University Identifier: NCT00721032     History of Changes
Other Study ID Numbers: NA_00011012
Study First Received: July 21, 2008
Last Updated: April 26, 2012

Keywords provided by Johns Hopkins University:
Ventricular tachycardia (VT)
Implantable cardioverter-defibrillator (ICD)
Electrophysiology study

Additional relevant MeSH terms:
Tachycardia, Ventricular
Arrhythmias, Cardiac
Heart Diseases
Cardiovascular Diseases
Pathologic Processes
Anti-Arrhythmia Agents
Vasodilator Agents
Potassium Channel Blockers
Membrane Transport Modulators
Molecular Mechanisms of Pharmacological Action
Sodium Channel Blockers
Cytochrome P-450 CYP1A2 Inhibitors
Cytochrome P-450 Enzyme Inhibitors
Enzyme Inhibitors
Cytochrome P-450 CYP2C9 Inhibitors
Cytochrome P-450 CYP2D6 Inhibitors
Cytochrome P-450 CYP3A Inhibitors processed this record on April 24, 2017