All concepts, explanations, trials, and studies have been
re-written in plain English and may contain errors. I am
not a doctor
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A-fib after heart surgery:

Dr. Peter Kowey said a-fib after heart surgery is seen in 40%
of patients after coronary surgery and 60% after valve surgery.
This may be related to sterile pericarditis and happens as
often with "minimally invasive" surgery as with traditional
surgery when one takes into account the severity of disease.
However, in valve disease a-fib frequency may be less with
minimally invasive techniques.
	He emphasizes that beta-blockers are the best and most
practical therapy to reduce post-surgery a-fib, especially if
the patient was taking them before the surgery.
	Blood potassium level is also very important. Dr.
Kowey stresses the importance of maintaining proper potassium
levels to reduce the frequency of a-fib after heart surgery.

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Blood Thinners For A-fib

Dr. Daniel Singer describes blood thinners used in a-fib. He
stresses risk factors like history of high blood pressure,
diabetes, prior TIA (mini-stroke) or stroke, and age. The
benefit of warfarin (Coumadin) has been shown in many trials,
although the benefit of aspirin has been less clear (SPAF and
EAFT trials).
	With warfarin, the relative risk reduction is 68%, or
an absolute risk reduction of 3.1% per year. In EAFT, the
relative risk reduction was 66%, with an absolute reduction
of 8.4%. Risk of serious bleeding with warfarin is low, at
0.3% per year versus 1% with aspirin.
	Dr. Singer says an INR range of 2 to 3 is best and
points out that the risk of stroke increases 2-fold when INR
falls to 1.7 or less. In his opinion, blood thinner therapy
is "defensible in all patients," but he usually recommends
aspirin alone in patients under age 65 with non-valve-caused
a-fib and no other risk factor.
	For those 65 to 75 years of age and with no other
risk factor, aspirin or warfarin is acceptable, although he
prefers warfarin. For all others - those over age 75 or those
with risk factors - he uses warfarin.
	Dr. Singer proposes that permanent blood thinner use
is reasonable, and that paroxysmal a-fib should be treated as
one would treat permanent a-fib. Although the American
College of Chest Physicians only calls for anticoagulation
for 4 weeks after conversion to normal rhythm, he recommends
longer therapy, only stopping the drug after "fairly long
periods of clear-cut normal rhythm."

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Non-drug Therapy For A-fib


Dr. Douglas Packer discussed non-drug therapy for a-fib,
pointing to the "good news" that several options are now
available. However, the "bad news" is that they are new and
not yet mature. Pacemakers, with new pacing sites, may hold
promise. The "ICD" for a-fib remains limited by pain from
shocks.
	Dr. Packer discussed several ablation techniques.
Linear left atrial ablation has enjoyed only limited success
(40 to 50%) with substantial risk of complications - mainly
stroke and pulmonary vein stenosis.
	Right atrial linear ablation has had success in only
about 20% of cases. Ablating focal arrhythmia triggers shows
promise but Dr. Packer emphasized that the best centers can
hope for only about 50% success with the first procedure, and
75 to 80% success after a repeat procedure. You can expect
pulmonary vein stenosis in about 1 to 3% of patients.
	Even with success, "parallel processes" such as high
blood pressure and aging can result in eventual a-fib
recurrence.
	A final procedure for relief with a good track record
is atrioventricular junction ablation. In a recent
meta-analysis, this reduced symptoms such as shortness of
breath and improved ability to be active.

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How and When to Start Drug Therapy

Dr. Eric Prystowsky addressed when and where to start atrial
stabilizing drugs. He encouraged the idea that unusual a-fib
causes should be treated according to the why they occur. For
example, vagally mediated a-fib with disopyramide,
sympathetically mediated a-fib with beta-blockers), alcohol
and caffeine-related a-fib with abstinence, and tachycardia-
induced a-fib with ablation. He said that caffeine's link to
a-fib is "overrated."
	According to Dr. Prystowsky, after consideration of
the cause you should choose drugs according to their safety,
as it applies to the underlying problem(s). Choices might
include propafenone for high blood pressure, amiodarone or
dofetilide for CHF, sotalol for coronary artery disease, and
either flecainide or sotalol (or propafenone) for lone a-fib.
While eliminating a-fib may be an unrealistic goal, reducing
symptoms is a reasonable goal of therapy.
	There is a debate about when to start an anti-arrhythmic
drug. The risk of torsade de pointes must be considered. Risk
for this is higher in women, those with established a-fib,
sinus nodal dysfunction, left heat emlargement, and slow heart
rate.
	Risk with class IC drugs can be reduced by good rate
control of a-fib before starting the drug. The risk of starting
another arrhythmia is much greater in patients with structural
heart disease.
	Dr. Prystowsky says most anti-arrhythmic drugs should
be started slowly and carefully. You must consider package
insert instructions that require starting a drug only in
inpatients - such as dofetilide.

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