Posted by Bob Reiley on April 27, 2001 at 15:11:17:
I have attached an e-mail I received from Dr. Cox that was in response to questions that I had asked him about my pacemaker. His response has a lot of good information in it.
Dear Mr. Reiley,
I am glad to hear that you "feel good, take no medications, and have had
no AF since surgery" after having AF for 10 years prior to surgery.
Obviously, I am sorry to hear that you are so unhappy about having a
pacemaker, though I certainly understand.
Let me explain a few things about the pacemaker situation in your
particular case. As you probably know, the Sinus Node is responsible for
generating the electrical beat of the heart and the AV Node is responsible
for conducting the electrical impulse from the two atria to the two
ventricles. About 20% of patients with AF have an abnormal Sinus Node before
surgery and they all require pacemakers after the Maze procedure. Because
this is such a common occurrence, we generally like to know the status of the
patient's Sinus Node before surgery so that we can tell that patient whether
or not he is likely to need a pacemaker following the surgery. In your case,
the Sinus Node was normal and therefore, we did not expect you to require a
pacemaker following surgery. My statement in the article that you quoted was
made in direct response to some previous allegations by others that it was
the Maze Procedure itself that CAUSED the patients to have pacemakers
following surgery because it somehow damaged the Sinus Node. My statement
was meant to point out that the Maze mayUNMASK an underlying abnormal Sinus
Node but if a patient had a normal Sinus Node BEFORE surgery, he would have a
normal Sinus Node AFTER surgery and therefore, would not have to have a
pacemaker.
The reason that we did not mention the possibility of needing a pacemaker
after surgery for abnormal AV NODE function was that an abnormal AV node
(i.e., heart block) is simply not a problem that we had seen before following
the Maze procedure except in two unusual circumstances. One was in a patient
in whom I found an abnormal cardiac vein in her heart that we had not known
about before surgery. I had to repair it at the time of surgery and in doing
so, damaged the AV Node. That occurred even though I have operated in that
specific area of the heart far more than any other surgeon in the world. The
second patient who developed heart block following the Maze procedure also
had two heart valves replaced in addition to the Maze procedure. Heart block
due to AV node damage in patients with extensive valve surgery such as his is
common and it was clearly due to the valve surgery in that patient, not to
the Maze Procedure.
Therefore, you are the only person with lone atrial fibrillation in our
experience who has required a pacemaker due to AV Node malfunction (heart
block). Furthermore, I have no idea why you should have heart block. I do
not think that your AV node was injured by the Maze procedure lesions. The
lesions that are used to create the Maze procedure are placed well away from
the AV node. In addition, many years ago in other patients with other
arrhythmia problems (not AF), we developed a technique in which we actually
CREATED heart block by freezing the AV node on purpose. Interestingly
enough, we found that it was extremely hard to do with a cryoprobe and that
fact makes it even less likely that we somehow inadvertently injured yours
during the Maze procedure.
I suspect that the abnormal function of your AV node after surgery is
more related to some underlying problem with it that was not detected before
surgery. However, regardless of what caused it, my strong opinion is that
its function will likely return within a few months. If and when that
happens, you will be able to remove the pacemaker that you have if you wish
to do so.
Let me mention a few things about what you might expect if for some
reason the AV node function never returns and you have to keep the pacemaker.
First, there are virtually no limitations on your life caused by having a
pacemaker. I have professional athletes, basketball players, wrestlers,
swimmers, skiers, marathon runners and even sky divers who have pacemakers in
and don't even bother to think twice about it. The pacemaker you have causes
the atria and ventricles to beat synchronously as they are supposed to beat.
In addition, the pacemaker responds to excerise so that if you are supposed
to have a higher heart rate, it will deliver one. Thus, your heartbeat is
essentiall normal and if you did not know that you had the pacemaker in, you
would be unable to tell it by your heartbeat.
Second, you do NOT have to worry about things like microwave ovens and
some of the other devices once avoided by pacemaker patients. The technology
that overcame those old problems was put in pacemakers nearly 20 years ago!
Since the pacemaker's status can be checked over the phone, it doesn't
require you to stay close to a doctor, etc. I generally tell my patients with
pacemakers to just forget that they have one and go on with whatever they
would normally do in their lives. We can tell over the phone a year or two
before the battery is going to wear out and to have a pacemaker fail in this
day is virtually unheard of. Even if it should suddenly stop working in you,
you will not drop dead. Your venticles have what is called an "escape rate"
that is usually around 30-40 beats and the heart will beat at that rate
WITHOUT a pacemaker...it's just that you would feel weak if your heart beat
at that rate all of the time.
My advice to you would be to follow your local doctor's orders and to
have your pacemaker checked whenever he has you scheduled to do so. In
addition, you should have an EKG at least at 6 months and at 1 year after
surgery. There are some other tests that you will need at 6 months as a
matter of routine follow-up after your surgery. I would suggest that you
forget about having a pacemaker and go on with your life. If your AV node
function returns in the next few months, then you can have the pacemaker
removed.
I hope that this e-mail will be of some comfort to you. I am sorry that
it has taken me so long to answer it. Best wishes for a happy Holiday Season
to you and your family.
James L. Cox,
M.D.