Drawing First Blood
We invite two experts to debate controversial
topics in hematology and health care
Should IVC Filters Still Be Inserted into
Thrombosis Management Guidelines?
Anita Rajasekhar, MD
Disclaimer:
The following positions were assigned
to the participants and do not
necessarily reflect ASH’s opinion, the
participants’ opinions, or what they
do in daily practice.
Agree? Disagree? We want to hear
from you! Send your thoughts and
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issue to ashclinicalnews@
hematology.org.
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ASH Clinical News
ASH Clinical News invited
Joseph M. Stavas, MD, and
Anita Rajasekhar, MD, to
debate the question: “Do
inferior vena cava (IVC) filters
still have a role in managing
thrombosis?” Dr. Stavas will be
arguing on the “pro” side, and
Dr. Rajasekhar will be arguing
on the “con” side.
https://en.wikipedia.org/wiki/Inferior_vena_cava_filter
Joseph M. Stavas, MD
Although the use of inferior
vena cava (IVC) filters to prevent
thrombosis has increased
dramatically in the past decade,
the risk-benefit ratio of these
devices is unclear. The potential
complications associated with
filter placement and retrieval
may outweigh the benefit,
particularly in the era of novel
oral anticoagulants.
Joseph M. Stavas, MD: When we think
about the potential risks of IVC filters,
we need to realize that these filters are
devices; any time a device is placed into
the body, there are risks associated with
its placement, failure, and retrieval –
some of which can be fatal.
The complications during
placement are routine types of accesssite problems, such as fistulas and
infections, but devices are imperfect
and may not deploy or may deploy in an
incorrect location. And, after decades
of experience, we now understand that
these filters can be thrombogenic in and
of themselves; for example, the device
can migrate into the heart and out into
the pulmonary circulation, causing a
pulmonary embolism (PE).
With the retrievable IVC filters that
have been developed in the last decade,
there are complications with filter
fracture, tilting, and migration through
the vessel wall that make retrieval
difficult. In these cases, aggressive
methods of retrieval are used and have
their own risks and complications.
Before we debate whether there is
still a role for IVC filters in thrombosis
management, we should describe what
the role of IVC filters has been. Forty or
50 years ago, IVC filters were developed
to prevent PE and deep-vein thrombosis
(DVT) and to lower the increased
mortality associated with any clot in the
iliac vein system.
I would think that most practices
that place IVC filters have seen many
of these complications – some due to
defects in the filter design or materials,
and some due to poor understanding of
what these filters can and cannot do.
Anita Rajasekhar, MD: I agree completely.
The sole purpose of an IVC filter is to
provide a mechanical means of preventing a lower-extremity DVT or a pelvic
DVT from embolizing to become a
potentially fatal PE. Anything outside of
that indication is not supported by data.
An IVC filter does nothing to
decrease a person’s inherent tendency
to develop a clot. In my practice, I see
many patients who are predisposed
to thrombosis – whether they have
cancer or some other provocation – and
placing a potentially thrombogenic
foreign device onto their veins does
them a disservice in the long term.
The acute complications you
mentioned are well-known but very
rare – occurring in 1 to 2 percent of
patients1 – but long-term complications
are the leading concern with IVC filter
placement. In 2010, the U.S. Food and
Drug Administration issued a safety
alert due to the number of adverse event
reports with retrievable IVC filters
(921 events in a five-year period).2
It should be noted that these were
voluntary reports, so the actual number
is probably higher. These adverse
December 2015