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Is It Time to Rethink AF Therapy with Patients?
To listen to an
interview with Eric N.
Prystowsky, MD, on
the application of AF
guidelines to clinical
practice, sca n the
code. The interview
was conducted by
David J. Callans, MD.
How to apply the AF guidelines in clinical practice
T
reatment of atrial fibrillation (AF) involves
three major strategies: prevention of stroke,
maintenance of sinus rhythm, and rate control.
Stroke is the most dreaded complication of AF, and its
prevention is key.
Eric N. Prystowsky, MD, is a pioneer in
electrophysiology and the cardiovascular disease
program director at St. Vincent Hospital in Indianapolis, IN. He was involved in the development
of the first two sets of AHA/ACC guidelines for
managing patients with AF,1 but rotated off the
guidelines committee for the most recent set.2
“We’re getting more and more choices to manage
AF,” he said. Some of the new guideline recommendations are confirming what we knew in the past, he
added, while others underscore “twists and turns.”
For example, we’re back to a controversy that
some people thought ended years ago in terms of
which is better: a rate or a rhythm control strategy. The issue seemed to be settled by the AFFIRM (Atrial Fibrillation Follow-up Investigation
of Rhythm Management) study, which suggested
rhythm-control offers no survival advantage over
rate-control strategy, plus there may be a lower risk
of adverse drug effects with a rate-control strategy.3
However, Dr. Prystowsky noted the mean age
of study participants was almost 70 (mean: 69.7
years) and mean follow-up was 3.5 years. AFFIRM
shows documented safety of persistent AF in a
small slice of the population, roughly age 62 to 72.
Moreover, more recent data suggests that patients
treated with rhythm control had reduced mortal-
One way to lower stroke
risk and better protect
the brain: assess risk
using the broader
CHAD2DS2-VASc risk
assessment tool.
22
CardioSource WorldNews
ity when follow-up was extended beyond 4 years.4
There are really no safety data, he said, regarding allowing patients to stay in AF for 20, 30, or
40 years. Given evidence of potential deleterious
effects of longstanding AF, such as cognitive effects,
dementia, and even Alzheimer’s (with the greatest
risk in those < 70 years of age), Dr. Prystowsky
said. “I am not telling you what to do. What I am
asking people to do is to rethink this issue with
your patients. There are new data suggesting that
leaving patients in AF is not as safe as you think.”
One change in the current guidelines: radiofrequency catheter ablation may be considered as
first-line therapy in select patients before a trial of
antiarrhythmic drug therapy when a rhythm-control
strategy is desired. The recommendation applies to
ablation done in experienced centers. That’s important, according to Dr. Prystowsky: “There was a paper published a couple years ago which was frankly
appalling to me, that suggests the vast majority of
AF ablations done in this country are being done by
those who do fewer than 25 a year.” While it’s a personal opinion and not a guideline, he added, “If that’s
all you’re doing in a year, perhaps you should rethink
whether you should be doing them.”
In terms of rate control, one change Dr. Prystowsky wholly supports relates to tight rate control.
In between the previous guidelines and the new
set, there was an interim update that gave strict rate
control a class III recommendation, meaning don’t
do it. “Many of us felt that was inappropriate and
I am really pleased that the latest guideline committee took that (issue) up.” A class IIa recommendation is now given to heart rate control (resting
heart rate < 80 bpm) as a reasonable strategy for
symptomatic management of AF. And lenient rate
control (resting heart rate < 110 bpm) dropped
down to a class IIb recommendation.
PRESERVE THE BRAIN
According to Dr. Prystowsky, the “prime directive
of AF management” is to preserve the brain. He has
written about this in JACC,5 emphasizing that stroke
is not the only neurological consequence of AF.
Cognitive impairment and silent cerebral infarcts
(SCIs) without clinical strokes have been reported
in patients with AF. “This is a passion of mine,” he
said, “and I think it is, unfortunately, not something
we always think about as much as we should.”
One way to lower stroke risk and better protect
the brain: assess risk using the broader CHA2DS2VASc risk assessment tool (class I recommendation).
With prior stroke, TIA, or a CHA2DS2-VASc score
> 2, oral anticoagulants are recommended (class I
recommendation) based on shared decision-making,
with a discussion of the risk
of stroke and bleeding and
patient preferences (also a class
I recommendation). “In my
own experience,” he said, “it
takes about 10 minutes to go
over this with my patients. It’s
a very important decision that
is well worth the time and then
you make a shared decision.”
In terms of choice of
anticoagulant therapy, warfarin versus a novel oral
anticoagulant (NOAC), Dr. Prystowsky offered his
own approach:
• Have an in-depth discussion with the patient
concerning the risks/benefits of various anticoagulant therapies.
• For the patient who is taking warfarin and
has had stable time in therapeutic range and
prefers not to change: leave well enough alone.
• For patients just starting anticoagulation who
have no reason to avoid a NOAC: prescribe a
NOAC.
“Personally, I don’t think you should push either
agenda,” he added. “Both are class I recommendations and I think it is up to you and the patient.”
BRIDGING
Bridging is always an important issue, and as Dr.
Prystowsky knows from having defended physicians, this is not an uncommon medico-legal issue.
He said he was pleased to see the guideline directives are clear (all class I; level of evidence C):
• Bridging therapy with LMWH or unfractionated heparin is recommended with a mechanical heart valve if warfarin is interrupted.
Bridging therapy should balance risks of
stroke and bleeding.
• Without a mechanical heart valve, bridging
therapy decisions should balance stroke and
bleeding risks against the duration of time
patient will not be anticoagulated.
• For atrial flutter, antithrombotic therapy is
r ecommended as for AF.
“If you have a mechanical heart valve, bridging is
important,” he said, “but honestly anything other
than that it is you decision with the patient based
on risks and benefits.”
It is a little different, he said, when the issue is
cardioversion. In the setting of AF or atrial flutter
(they are treated the same for cardioversion), the
guidelines recommend (all class I):
• With AF or atrial flutter for > 48 hours, or un-
September 2015