DE-MRI Determinant of Successful Radiofrequency Catheter Ablation of Atrial Fibrillation (DECAAF).
Background and Introduction:
Atrial fibrillation (AF) is an electrophysiological condition characterized by a disorganized electrical activity involves the entire atria. AF manifests initially as paroxysms of arrhythmia that later progress into persistent and permanent forms. AF is more prevalent with advancing age and is associated with structural heart disease including hypertension, systolic and diastolic ventricular dysfunction and valvular heart disease. It represents a significant public health problem with the increasing longevity of the general population. AF is associated with a substantial stroke risk, diminished quality of life and increased mortality. It is a progressive disease associated with structural, electrical and contractile changes in the left atrium (LA). A major determinant of the progression of AF is structural remodeling (fibrosis) that occurs in the left atrium. A more extensively remodeled atrium represents the substrate needed for the arrhythmia to persist. Structural remodeling is also a major determinant for success of rhythm control strategies in AF. While catheter ablation has been reproducibly shown to be superior to anti-arrhythmic drug therapy for rhythm control in AF, the success of this procedure is significantly affected by the extent of structural remodeling present at the time of catheter ablation.
Delayed-Enhancement Magnetic Resonance Imaging (DE-MRI) has been demonstrated to be a very effective modality in identifying fibrotic and scarred cardiac tissue. This is related to the characteristics of Gadolinium, an extracellular contrast agent that is very effective in identifying regions of fibrotic non-viable myocardium. DE-MRI technology can be a very powerful, non-invasive method, of identifying the extent and the distribution of structural remodeling or fibrosis associated with AF.
The ongoing research at the University of Utah in applying DE-MRI technology to the atrium has shown significant progress and very promising results. Used prior to catheter ablation, DE-MRI can identify regions of significant structural remodeling or fibrosis. The same technology has also been shown to be very useful in examining the amount and distribution of ablation related scarring.
This study seeks to expand the University of Utah experience with DE-MRI image acquisition and processing in the management of atrial fibrillation.
Aim 1: Successfully acquire DE-MRI scans of the left atrium in AF patients and quantify the extent of structural remodeling or fibrosis.
Aim 2: Successfully acquire DE-MRI scans of the left atrium 3 months post catheter ablation, quantify the extent of ablation related scarring and describe its distribution
Aim 3: Evaluate the relative contribution of clinical patient characteristics, pre-ablation fibrosis as well as post-ablation scarring in determining the long-term success of catheter ablation in maintaining normal rhythm.
1.Patients undergoing their 1st AF ablation as per recent Heart Rhythm Society (HRS) consensus document (4).
2.Able to understand and willing to sign the Informed Consent Form.
3.Age ≥18 years.
1.Contraindication for DE-MRI with a full dose of Gadolinium-based contrast agent.
2.Previous left atrial ablation or surgical procedure
3.Renal failure with CrCl <60 ml/min
4.Women currently pregnant, breastfeeding, or of childbearing age not currently taking or not willing to use a reliable form of contraception
5.Mental or physical inability to take part in the study
7.Morbid obesity (BMI > 35), or inability to be placed in MRI due to body mass.
For more information about site participation in the DECAAF study, please contact firstname.lastname@example.org
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