No procedure is impossible in medicine . . . but it should be useful for the patient !
Where will you ablate ? What is the purpose ?
The much hyped* ablation of pulmonary vein is never going to help in rheumatic heart since arrhythmia focus occurs at random . How can you locate a focus of AF over a huge , scarred left atrium ? ( which looks like a lunar surface sprinkled with a rocky terrain ! )
Note the huge , scarred LA .It would
be a wild guess to locate the true focus
of AF . (Image source : http://www.e-heart.org)
So , the other option was disconnecting atria electrically . In the past surgeons advocated linear or multiple incisions as in Maze and Corridor procedure after mitral commissurotomy .This helped to a certain extent , still effective , organised atrial contraction was not restored in many.
Now , some electrophysiologists tried to do the same with catheters without much benefit.* Please realise , pulmonary vein ablation even in lone and ischemic AF is struggling with a concept collision !
Can Right atrial focus trigger and sustain AF in RHD ?
Autopsy studies reveal tricuspid valve scarring in 33% of all RHD .Since RHD is a diffuse process , RA lesions can be very well be the focus . It is not an easy task to identify the real culprit focus. So ,concentrating LA for ablation may end up in futility.
There are only few studies available on RF ablation in RHD .This one from Istanbul ,Turkey and it does not favor it as recurrence rate is still significant .
Final message
Approach to AF in RHD : Opening up the mitral valve (or replacing it ) and controlling ventricular rate with beta /calcium blocker along with adequate oral anti-coagulation substantially reduce the risk of embolic events .One may never need to contemplate restoring sinus rhythm in rheumatic atrial fibrillation.
//
Dr.S.Venkatesan MD 