Friday, January 06, 2012


Much has been written about radiofrequency ablation in the treatment of atrial fibrillation. Since, the pioneering work of Dr Michel Haissaguerre in 1990s, this technique has gain popularity as it avoids the risk of cardiac surgery and the Maze-Cox procedure to try and eradicate atrial fibrillation. I have been following the work, and although all my colleagues tell me that the procedure is good, easy and highly successful, I had my doubts, and have continued to keep my chronic AF patients on long term anticoagulation with warfarin and also rate control, getting the heart rate down to 60-70 beats per minute. I ws not convinced that the procedure is simple, as I see that the catheters are complicated and they are working, almost blindly in a large left atrial chamber. To me, it needs some skill and of course very good training and guidance. The super specialist in dedicated centers that do 100 a year are like ly to get good results and those that do the occasional ( 1-2 a month ) are likely to have disasters.
Well this blog is partly prompted by a paper in the Journal of the American College of Cardiology, Jan 10th 1012, authored by Dr Rashme Shah of the Cedar Sinai Medical Center, USA. They reviewed 4,156 cases of RF ablation for Atrial Fibrillation from the Healthcare Utilisation Project California State Inpatient Data base, to see the outcomes of patients who had undergone RF ablation for AFib. This will mimick real world pratice as the data base will have outcome data from academic centers of excellence that do 100 cases a year, and some medicare institutions that do a handful of cases. What they found is very revealing.
Of the 4,156 cases on record, there was a peri-procedural complication rate of 5.1%. Half of these were bleeding and half were cardiac tamponade. There was also one death and 10 strokes.
Of those who survive, about 9.4% had to be readmitted within 30days mainly for recurrence of AFib / AFlutter, although deem procedural success after the procedure. 2.3% died within 30days and 4.9% ( about 200 ) had a stroke within 30days.
We are not told the procedural success rates. I guess that it must be around 60-70% at the academic institution and about 30-40% at the medicare centers.
Within 1 year, about 20% had a recurrence of AFib and at 2 years 30% had recurrence. These would require a repeat, and it is not uncommon to have 2-3 ptrocedures in 5 years.
Well, to me, the numbers are not so encouraging. It is obviously a tough procedure to master and the current equipment may need much improvement.
So, I am not so wrong in keeping to good old medical therapy of rate control and anticoagulation , different degree for different AFib disease subsets. I still use aspirin for those with low CHAD scores, and warfarin for those with high CHAD scores. This strategy has work well with me and my patients.
I firmly believe that the practice of medicine must have good basic theory, sound medical reasoning and good clinical data to back up. Each without the other can lead to harmful practice.

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