Feasibility of gadofosveset-enhanced 3.0T cardiac MRI: quantitative comparision with non-enhanced cardiac MRI at 3.0T and 1.5T.

Non-invasive diagnosis of cardiovascular diseases is strongly emerging.
Intra-arterial digital subtraction angiography used to be the standard of
reference for many clinical indications, but nowadays newer techniques like
echo-doppler, computer tomography (CT) and magnetic resonance imaging (MRI) are
more widely used. The latter, MRI, is currently considered to be the standard
of reference for studying heart function and size of myocardial infarctions.
Untill now, most cardiac MR studies have been performed at 1.5T MRI scanners.
Recently, 3T MRI scanners have become clinically available. At high field
strengths higher spatial resolution and shorter scan duration can be achieved.
Additionally, better visualization of myocardial perfusion might be obtained at
3T because of altered relaxivity of contrast agents at this field strength.
A major disadvantage of 3T MRI scanners is a the occurence of artefacts due to
magnetic field inhomogeneities. However, a recent study demonstrated a
beneficial effect of intravascular contrast agents: artefacts were reduced at
3T when using the intravascular agent gadomer-17. In our study we will use
Gadofosveset, an intravascular albumin binding contrast agent (reversible
binding). It has a longer intravascular half life and a higher relaxivity
compared to other, extravascular contrast agents. This results in higher signal
intensity, even when using a relatively low dose of the contrast agent.

To study the feasiblity of cardiac MRI at 3T and the potential benefits of the
intravascular contrast agent gadofosveset for studying and quantifiaction of
heart function and -perfusion.

In this pilot study cardiac MRI at 1.5T and 3T will be compared. At 1.5T the
current clinical protocol will be used to detect wall motion disturbances,
abnormalities in perfusion and myocardial infarction. Within several weeks
after the first MRI, a similar study will be performed at 3T, but with adjusted
acquisition parameters compensating for higher field strength. Additionally,
wall motion sequences will be performed after administration of the contrast
agent gadofosveset.

MRI is a diagnostic tool with minimal burden for the patient. The use of
contrast agents is associated with minimal risks. However, side effects of MR
contrast agents are rare and, if they occur, they can generally be treated
well. In previous trials with Gadofosveset, this agent has demonstrated to be
useful and safe.