NCT00721032

Brief Summary

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 electrophysiology (EP) lab for mapping and entertainment 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.

Trial Health

30
At Risk

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Trial has exceeded expected completion date
Timeline
Completed

Started Jun 2012

Typical duration for not_applicable

Geographic Reach
1 country

1 active site

Status
withdrawn

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

July 21, 2008

Completed
2 days until next milestone

First Posted

Study publicly available on registry

July 23, 2008

Completed
3.9 years until next milestone

Study Start

First participant enrolled

June 1, 2012

Completed
3.2 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

August 1, 2015

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

August 1, 2015

Completed
Last Updated

May 10, 2017

Status Verified

May 1, 2017

Enrollment Period

3.2 years

First QC Date

July 21, 2008

Last Update Submit

May 9, 2017

Conditions

Keywords

Ventricular tachycardia (VT)Implantable cardioverter-defibrillator (ICD)AblationCardiomyopathyElectrophysiology study

Outcome Measures

Primary Outcomes (1)

  • Freedom from ventricular tachycardia documented by implantable defibrillator cardioverter 6 months post ablation.

    6 months

Secondary Outcomes (4)

  • inducible arrhythmia at the end of the procedure,

    During procedure

  • Procedure time

    During procedure

  • Comparison of endocardial voltage mapping to scar on delayed enhancement MRI images

    During procedure

  • Complications of the procedure

    30 days following procedure

Study Arms (2)

1

EXPERIMENTAL

Magnetic resonance imaging (MRI)-guided ablation of ventricular tachycardia.

Procedure: MRI guided VT ablation

2

ACTIVE COMPARATOR

Anti-arrhythmic group.

Drug: Increased dose of amiodarone

Interventions

Magnetic resonance imaging (MRI)-guided ablation of ventricular tachycardia (VT)

1

Increase the dose of amiodarone according to the following scheme: current dose -\> new dose 100 once daily (QD) -\> 200 QD; 200 QD -\> 400 QD; 300 QD -\> 600 QD; 400 QD -\> 600 QD

2

Eligibility Criteria

Age18 Years - 99 Years
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • 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 radiofrequency ablation (RFA)

You may not qualify if:

  • 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
  • Glomerular Filtration Rate (GFR) \< 30 ml/min

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Oregon Health & Science University

Portland, Oregon, 97239, United States

Location

MeSH Terms

Conditions

Tachycardia, VentricularCardiomyopathies

Condition Hierarchy (Ancestors)

TachycardiaArrhythmias, CardiacHeart DiseasesCardiovascular DiseasesCardiac Conduction System DiseasePathologic ProcessesPathological Conditions, Signs and Symptoms
0

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
NONE
Purpose
TREATMENT
Intervention Model
PARALLEL
Sponsor Type
OTHER
Responsible Party
SPONSOR

Study Record Dates

First Submitted

July 21, 2008

First Posted

July 23, 2008

Study Start

June 1, 2012

Primary Completion

August 1, 2015

Study Completion

August 1, 2015

Last Updated

May 10, 2017

Record last verified: 2017-05

Locations