Feasibility of Contact Force Catheter Mapping and Ablation in Epicardial and Endocardial Ventricular Tachycardias (EPICONTAC-VT)

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT01847378
Recruitment Status : Unknown
Verified October 2014 by Lucas Hollanda, Federal University of São Paulo.
Recruitment status was:  Recruiting
First Posted : May 6, 2013
Last Update Posted : October 21, 2014
Information provided by (Responsible Party):
Lucas Hollanda, Federal University of São Paulo

May 2, 2013
May 6, 2013
October 21, 2014
June 2013
May 2015   (Final data collection date for primary outcome measure)
Evaluate the feasibility of mapping and ablating ventricular tachycardias in endocardial and epicardial using a contact force catheter [ Time Frame: Immediatly after the procedure ]
The feasibility will be evaluated immediatly after the procedure
Same as current
Complete list of historical versions of study NCT01847378 on Archive Site
Evaluate the impedance and voltage threshold for scar in chronic chagasic cardiomyopathy [ Time Frame: After the procedure ]
Same as current
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Feasibility of Contact Force Catheter Mapping and Ablation in Epicardial and Endocardial Ventricular Tachycardias
EPIcardial and Endocardial Mapping and Ablation Using Contact Force Catheter in Chagasic Patients With Sustained Ventricular Tachycardia

Ventricular tachycardia is one of the commonest cause of sudden death in chronic chagas disease. As most ventricular tachycardias originate from scar in patients with heart disease, catheter ablation is an important step in patient treatment. Identification of fibrosis prior to ablation of sustained ventricular tachycardia (SVT) might reduce the time of anesthesia, procedure time, radiation exposure and possibly the risk of complications. Knowledge of arrhythmia circuit within scar allows planning strategies for each procedure. Condreanu et al. stablished that voltages inferior to 6.52 mV (unipolar) and 1.54mV (bipolar) are useful tools in detecting scar during electroanatomic mapping. Accuracy, however when compared to magnetic resonance imaging is limited due to difficulties in maintaining good contact between ablation catheter and ventricular wall. Contact force catheters might help increase accuracy of voltage mapping because they allow detection of poor contact areas. Although the threshold for identification of scar in ischemic and non ischemic patients during electroanatomical mapping is already known, this parameters still lacking for chronic chagasic individuals. A marked qualitative histological difference between these fibrous scars supports the hypothesis that voltage scar in chagasics might be different. Catheter ablation contact with endo and epicardial surface is an important issue when ablating arrhythmias. Conventional catheter ablation is not equipped with sensors capable of detecting degree of contact with the target. To our knowledge, the literature lacks information in regard to late lesions produced by a known contact force pressure "in vivo". The pattern of electrical activation in these patients and their relationship with local coronary veins for resynchronization likely to approach through the coronary sinus can be useful in defining chagasic that can benefit from resynchronization.

  1. Compare endocardial and epicardial impedance and voltage using CARTO 3 with fibrosis on 3T MRI
  2. Correlate areas of late activation within scar during activating mapping in sinus rhythm with different signal intensity in 3T MRI
  3. Evaluate the influence of contact pressure during application of radiofrequency in making fibrosis analyzed 30 days after the procedure using a 3T MRI.
  4. Assess the site of latest left ventricular activation in sinus rhythm and correlate with the coronary veins location
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Observational Model: Cohort
Time Perspective: Prospective
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Probability Sample
Chagasic patients with symptomatic documented ventricular tachycardia
  • Ventricular Tachycardia
  • Sudden Death
  • Syncope
  • Chest Pain
Procedure: Catheter ablation
During mapping and ablation tissue voltage and impedance will be stored and analyzed thereafter. The same procedure will be done in regard to activating maps.
Catheter ablation
Patients with chronic chagasic disease and documented monomorphic ventricular tachycardia
Intervention: Procedure: Catheter ablation
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*   Includes publications given by the data provider as well as publications identified by Identifier (NCT Number) in Medline.
Unknown status
Same as current
August 2015
May 2015   (Final data collection date for primary outcome measure)

Inclusion Criteria:

  • individuals aged between 18 and 80 years old
  • life expectancy greater than 1 year
  • positive reaction in at least two different serologic techniques for Chagas disease (ELISA, indirect hemagglutination or indirect immunofluorescence)
  • symptomatic recurrent monomorphic ventricular tachycardia (recorded by holter, electrocardiogram or looper)
  • prior to implantable cardioverter defibrillator implantation in patients with ventricular tachycardia as an attempt to prevent shoks
  • patients in "electrical storm", defined as three or more episodes of ventricular tachycardia in 24h. Each episode must demand a medical intervention.
  • monomorphic ventricular tachycardia induced during electrical physiological study in patients with syncope of unexplained cause

Exclusion Criteria:

  • claustrophobia
  • creatinine clearance inferior to 30ml/min/m2 (clearance between 30ml/min/m2 and 60ml/min/m2 will be analyzed individually)
  • thrombus in the left ventricle
  • pregnancy
  • heart failure NYHA IV
  • allergy to iodinated contrast or gadolinium
  • patients with implantable devices (pacemakers, implantable defibrillators and similar)
  • coagulopathy (INR > 1,5 or aPTT 2x normal values)
  • platelet count inferior to 100.000
Sexes Eligible for Study: All
18 Years to 80 Years   (Adult, Older Adult)
Contact information is only displayed when the study is recruiting subjects
Not Provided
Not Provided
Lucas Hollanda, Federal University of São Paulo
Federal University of São Paulo
Not Provided
Study Director: Claudio Cirenza, MD, PhD Federal University of São Paulo
Study Chair: Angelo AV de Paola, MD, PhD Federal University of São Paulo
Principal Investigator: Lucas H Oliveira, MD Federal University of São Paulo
Federal University of São Paulo
October 2014