EDITOR’S CORNER
Alfred A. Bove, MD
Interim Editor-in-Chief, CardioSource WorldNews
New Data that Change Practice
I
n this edition of CWSN, we hear about the annual
American Heart Association scientific sessions
that were held in cold Chicago in November. We
usually attend a scientific meeting such as this with
some expectation of interesting data that will ultimately lead to newer guidelines and improved care.
It is uncommon to head back from the meeting with
provocative findings that promise to quickly change
the way we practice cardiology.
The LDL discussion continued at this meeting.
Two important papers were presented. One presented the results of IMPROVE-IT, which examined
the benefit of ezetimibe when added to simvas tatin
for the reduction of cardiac events after an initial
myocardial infarction (MI). Average follow-up was
6 years and the study was conducted over a 10-year
period. The data showed a 6.4% reduction in the
combined primary endpoint (all cardiovascular
events), and a 13% reduction in MI. The LDL level
in the combined therapy group was 54 mg/dl. The
study rekindles the argument for LDL targets since
the lower LDL was associated with significantly reduced cardiovascular events and was achieved with
a non-statin (ezetimibe).
The second trial came from the original
investigators from the West of Scotland study
(WOSCOPS) who presented their 20-year followup data. Because the medical records for the government health system in Scotland are archived,
they were able to obtain mortality data on nearly
all of the original study patients. Over the 20
years there was a 27% risk reduction for coronary
mortality and a 13% risk reduction for all cause
mortality in patients randomized to pravastatin
compared to placebo. Their data support the
concept that lower LDL is associated with reduced
cardiovascular mortality.
These two studies offer compelling evidence that
we should be aiming for LDL targets and, while the
guidelines released in 2013 discourage using LDL
targets and focus on statin therapy, here we see
data supporting the LDL hypothesis.
In my practice, when a patient has an indication
for a statin based on the new risk calculator, they
universally ask about the target LDL. To provide
motivation, I still feel compelled to blurt out a
number like 100 or 70 depending on the patient’s
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CardioSource WorldNews
“ he DAPT trial
T
challenges our
thinking on
duration of dual
antiplatelet
therapy.”
cardiovascular disease status, and to aim for the
target, but with less compulsion.
Adding to the discussion, there were still more
PCSK9 studies reported at the AHA meeting.
ODESSY ALTERNATIVE reported the effects of
the PCSK9 inhibitor alirocumab in statin intolerant patients. As expected there was a significant
reduction in LDL with alirocumab (42%) compared to ezetimibe (15%) after 24 weeks. We still
are waiting for clinical outcome data from the
use of PCSK9 inhibitors, as this will, if positive,
clearly indicate that lowering LDL is the key
component to the cardiovascular risk reduction
demonstrated in the statin trials.
Another thought - provoking trial was the dual
antiplatelet therapy (DAPT) trial. The duration
of dual antiplatelet therapy is 1 year in some
guidelines, but several recent trials have indicated that even 3 months total therapy was a safe
alternative. Yet we hear the occasional anecdotal
report of a patient stopping dual antiplatelet
therapy 3 or 4 years after insertion of a drug
eluting stent (DES) and experiencing an acute
coronary syndrome from stent thrombosis. At
the AHA meeting, data from DAPT were presented comparing 1 year to 30 months of therapy
with dual antiplatelet therapy in nearly 10,000
patients who received either bare-metal or DES
for coronary disease. The patients entered the
study if they were event free 1-year post stenting
and were compliant with their dual antiplatelet
medications. The patients were randomized to
either DAPT or placebo for 18 months. Major adverse cardiac or cerebrovascular events (MACCE)
were significantly lower in the 30-month versus
12-month treatment group albeit with more
moderate and severe bleeding in the 30-month
treatment group. In the first 12 months post
stent placement, the patients with a BMS taking
DAPT experienced more stent thrombosis than
patients with a DES.
The DAPT trial challenges our thinking on
duration of dual antiplatelet therapy. It appears
that 30 months provides a benefit in terms of
cardiac MACCE at the expense of more bleeding.
Interestingly, the reduction in MACCE was divided
between MI and stent thrombosis. Not all of the
events were caused by stent thrombosis. This
suggests that DAPT is not only reducing risk for
stent thrombosis, but also reducing risk for an MI
caused by other coronary lesions.
These trials involving therapy for hypercholesterolemia and for preventing stent thrombosis
post-PCI challenge current guidelines and are
likely to result in changes in guidelines in the
future. If your patients ask for an LDL target,
provide them with a number while we await more
trial information to support targets. If your patient
asks when to stop their dual antiplatelet therapy,
suggesting 30 months or longer may not be unreasonable until we have further data. ■
Alfred A. Bove, MD, PhD, is professor emeritus of
medicine at Temple University School of Medicine in
Philadelphia, and former president of the ACC.
December 2014