2014 Boston AF Symposium
Bordeaux Approach to Ablation of Persistent A-Fib—ECGI & Circular Catheter
Report by Dr. Steve S. Ryan, PhD
Dr. Pierre Jais of IHU LIRYC in Bordeaux, France made a presentation entitled “Bordeaux Approach to Ablation of Persistent AF: Techniques and Results.” (It’s recommended to read Dr. Haissaguerre’s presentation 2014 BAFS “How ECGI Works” first, since Dr. Jais’ presentation builds on it.)
Bordeaux Five Step Protocol
Dr. Jais began by reviewing the highly successful Bordeaux protocol for ablating cases of persistent A-Fib. (See my 2007 report: Bordeaux Five-Step Ablation Protocol for Chronic A-Fib.)
They achieved a 95% success rate after two ablations. If they could terminate the A-Fib during the ablation, there was very little recurrence. (In difficult cases or in cases that last a long time, EPs may, for example, restore a patient to sinus rhythm by Electrocardioversion rather than terminating the A-Fib.) Predictors of recurrence were Coronary Artery Disease and Congestive Heart Failure.
ECGI & persistent A-Fib
With the new ECGI non-invasive mapping to guide ablation for persistent A-Fib
- Ablation targets driver regions starting with the most active. They spend a minimum of 5-15 minutes applying RF to a particular region using linear or brushing (ablating while moving the catheter). Most driver regions exhibit rapid and complex fractionated electrograms (CAFEs) but these CAFEs are not specific
- The end point is regional slowing (they may have to work in the appendages and the Coronary Sinus)
- Linear ablation is optional if A-Fib persists
In these persistent A-Fib cases, Pulmonary Vein Isolation terminated A-Fib in only 16% of cases.
In driver regions they found more rotors (80%) than focal drivers (20%).
They found multiple interplaying driver regions (median 4, 1-7) located in the Left Atrium, Pulmonary Veins and Right Atrium.
They found that the rotors were temporally and spatially unstable rather than sustained. Rotors moved slightly and usually lasted through only 2-3 rotations. Rotors required a specific phase mapping algorithm to be visible. Then a computer statistically analyzed their core trajectory and density.
Multielectrode (Circular) Catheter
Dr. Jais described and showed slides of how they use a Multielectrode (circular) catheter (Biosense Webster) to ablate and isolate driver regions. Even if there is some slight movement of the rotors, the circular catheter will still modify the substrate and isolate the region containing the rotors.
In Bordeaux’s experience of persistent A-Fib ablation using the Multielectrode circular catheter, procedure time was slightly over two hours, fluoroscopy time less than ½ hour, and RF application time was only around 20 minutes. (These are significant reductions compared to the older Bordeaux five step protocol.) They were also able to make a roof line block and Cavo Tricuspid Isthmus (CTI) line block with the Circular RF catheter. (A CTI line is a common strategy performed in the right atrium to prevent Flutter.)
In the revolution study of paroxysmal A-Fib, PVI was performed using the Multielectrode circular catheter, entrance block was confirmed in 98.7% of cases. Freedom from recurrence after eight months was 70.8%. There were two cases of Tamponade (1.2%) but no lasting complications like stroke, esophageal fistula or severe stenosis. The study also tested for asymptomatic events and associated neurological deficits following RF ablation, comparing the Circular catheter to a control group using an irrigated single tip catheter. They did a neurological examination and MRI 48 hours before the ablation, and the same examination 1-2 days after the ablation. No patients had symptomatic cerebral events. But 20% had asymptomatic CME (cerebral microemboli) as seen on MRI when using the Multielectrode circular catheter.
Dr. Jais’ presentation featured a further development of the ECGI system—the circular Multielectrode catheter which seems better designed to ablate foci and rotor regions in the heart.
ECGI combined with the circular catheter… will change and improve the way ablations are performed, not just for persistent but for all types of A-Fib.
This completes the package! ECGI combined with the circular catheter seems ready for prime time. This is one of the most important, ground breaking developments in the treatment of A-Fib. It will change and improve the way ablations are performed, not just for persistent but for all types of A-Fib.
Difficult persistent A-Fib ablations have been known to last 7-9 hours. With the ECGI and circular catheter, ablations times were slightly over two hours! (That’s less time than many centers use for simple paroxysmal ablations.) They needed much less fluoroscopy, mostly because ECGI mapped the heart noninvasively the day before the procedure. 20 minutes of RF application time is an incredible reduction in burns applied to the heart compared to previous persistent ablation strategies. And it tested out as safe with no lasting complications.
This is wonderful news for us. Once this protocol makes its way through the FDA, etc., it will usher in a whole new, improved level of treatment for A-Fib patients.
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