What is the potential diagnostic value of distention and intima-media thickness measurement for the early detection of endofibrosis and is there a link between the development of endofibrosis an the coagulation activation potential of the blood?

Endofibrosis is an disease affecting 15-20% of the young (17-30 years old)
professional cyclists and speed skaters. The disease is characterized by
fibrotic tissue formation in the iliacal artery, resulting in a stenosis. As a
result of this the bloodflow is reduced, resulting in unilateral ischemic
symptoms.
To date the mechanism behind this fibrotic tissue formatiion is still unkown.
However, the development of the fibrotic tissue formation is linked to
activation of Protease Activated Receptors (PARs) by active coagulation
factors. It's known that activation of these receptors by active coagulation
factors can affect the vessel wall composition, however data is fragmented and
the underlying mechanism is not known yet. So information about this could
provide new insights in these processes and it can possibly be linked to the
development of endofibrosis.
Endofibrosis is irreversible, so an surgical intervention is needed to solve
the problem. Endofibrosis is with the current diagnostic methods (Duplex and
Magnetic Resonance Angiography) only detectable in an late phase of the
disease, when the patient already experiences significant symptoms. Recently a
new diagnostic method is developed, with which vessel wall changes can be
detected in an earlier stage. This method is based on intimal-media thickness
(IMT) en distention measurement of the vessel wall by echography.
Since recent researche found a new therapeutic target to inhibit fibrotic
tissue formation in an early stage, early detection of the disease plays an
important role to set up an noninvasive therapy.

1. To investigate a possible increase intimal-media thickness (IMT) is found of
the iliacal artery in endofibrosis
2. To investigate a possible altered distention is found of the iliacal artery
in endofibrosis
3. To compare IMT and distention measurement of the iliacal artery with the
current diagnostic methods Duplex and Magnetic Resonance Angiography for the
detection of endofibrosis.
4. To study if an higher concentration of active coagulation factors is found
in persons with endofibrosis comparing to healthy persons.
5. To investigate if persons with endofibrosis have an higher coagulation
potential compared to healthy persons.

The study is an observational study. The subjects for the group of healthy men
will be recruited through advertisements and flyers that will be distributed
across the University of Maastricht. Through these ads and flyers can possible
participants contact the researchers. In addition, persons who qualify for the
group of persons diagnosed with endofibrosis who have not undergone any
treatment and the group with suspected endofibrosis, which based on a recently
created MRA and ultrasound doppler will be asked by Dr.Goof Scoop if they are
interested to be approached to participate in the study, this will take place
during the appointment that these people have with dr. Goof Spoon at the Maxima
medical Centre in Veldhoven. Dr. Goof Scoop will clearly indicate that
participation in the study independent of treatment undergone by the person and
that participation is voluntary and without consequences for the dependency
relationship with the doctor. If this person will accept that a researcher will
contact this person by telephone to provide information about the study. After
further consent, the information letter and informed consent will be handed
over to this person and the participant has two weeks to decide to decide
whether the person wants to participate in the study. If the person decides to
participate, he will be contacted by phone for an appointment for the research
at the University of Maastricht (MUMC + 2nd floor CARIM research lab). During
the event, the participant will be informed again and if approved he will sign
the informed consent in the presence of the researcher. The researcher will
notify the participant again that it is at all times have the right to decide
to no longer participate in the study, without any consequences being attached.
The study will be divided into different test days. For each test day, a
maximum of 4 subjects are used, depending on the availability of the group, the
investigators and the sonographer. It is expected that a total of 20 days will
be needed. This test days we want to try to plan within six months of each
other. The echo will be made in the examination room of the CARIM (MUMC + 2nd
floor CARIM research lab). For the study, the participant will be asked to fill
in a blinded questionnaire based on the participant code. Thereafter, the
sonographer (J. on the Roodt) will make the ultrasound images of the a. Iliaca
communis, and a. Iliaca externa, after which the images are stored blinded on a
code-protected hard disk that is in the administration of the researchers (A.
Lepper and J. Posthuma). The analysis of the images and the determination of
the IMT and distension will be done by the researchers (A. Lepper and J.
Posthuma). Also, 30 ml of blood will be collected from the participants, this
blood test will be done at the research lab CARIM in MUMC + 2nd floor .. The
blood is used immediately after purchase for a clotting test. And the results
of the various groups will be compared to both healthy as well the participants
with suspected endofibrosis and diagnosing endofibrosis.

For the participants, there are similar risks for normal venipuncture, which is
hematoma and bleeding at the site of the puncture. Furthermore, there are
similar risks for the participants as a normal echo, of which no adverse
effects are known.