The following information is provided to other physicians regarding our atrial fibrillation procedures.  It is technically complex and is provided here for patient review for informational purposes

Atrial fibrillation , as you know, is a common debilitating and difficult to treat arrhythmia.  Treatments of atrial fibrillation include serial drug trials and AV nodal ablation combined with pacemaker insertion.  These treatments however are palliative and not curative.

Recently, it has become evident that in the vast majority (>90%) of patients, atrial fibrillation arises from certain fixed structures in the heart.  If the originating sites for atrial fibrillation can be eliminated, so too can the arrhythmia.  Ablation of atrial fibrillation targets these sites.  Arrhythmogenic sites for atrial fibrillation and the approximate incidence of these structures as the culprit cause of AF are as follows;

1.        The left upper, right upper and left lower pulmonary veins:   60% (combined)

2.        The right lower and (if present) intermediate vein:  10%

3.        The superior vena cava: 10%

4.        The coronary sinus vein of Marshall (if present):    5%

5.        The left atrial isthmus region:  5%

6.        Other structures including the crista terminal and LA posterior wall:  Remaining 10%

The ablation of atrial fibrillation requires catheter isolation of these structures from the rest of the heart.  In many patients, the primary culprit site for the origination of AF cannot be definitively identified thus during the catheter ablation the “usual suspects” are ablated.  The ablation thus generally combines veno-atrial isolation of the three most arrhythmogenic pulmonary veins, the SVC and perhaps additional structures depending on the physiology uncovered during the procedure.

Utilizing this approach, we have been able to achieve success in approximately 70% of patients ablated.  These patients achieve long term cures of atrial fibrillation off all anti-arrhythmic drug therapy.  As for the remaining approximately 30% of patients, the majority will continue to have atrial fibrillation – although in most of these individuals episodes are less frequent or are more easily controlled with previously ineffective anti-arrhythmic drug therapy.

The right and left upper pulmonary veins; Common PAF origination sites

Risks of this ablation include the usual risks associated with any SVT ablation and approximately a 1% risk of catheter mediated stenosis of the pulmonary veins.  Venography of the targeted pulmonary veins is performed prior to and following ablation delivery in all of our patients.  The procedure, while technically complex, is entirely percutaneous and is performed on an out-patient basis for most patients.

Typical intra-cardiac electrograms obtained (simplified representation)

Patients most likely to achieve cure of atrial fibrillation from this ablation include patients with normal atrial sizes on echo.  Large atrials (either the right or left) often have multiple foci for A. Fib making this procedure less successful.  Age and chronicity of the atrial fibrillation appears to be less important considerations.  Patients with longstanding persistent A. Fib can be cured via this approach as can older patients.

This series of electrograms shows the connection points between a pulmonary vein and the left atria.  These connection points are ablated eliminating the electrical communication between the arrhythmogenic pulmonary vein and the heart.  In reality, over many more electrograms are obtained and a 3-dimensional map of the veno-atrial connection points is made prior to ablation delivery.  This is done for ach pulmonary vein targeted as well as any other arrhythmogenic structures targeted