Towards a non-invasive anatomical and functional diagnostic work-up of patients with suspected coronary artery disease using Cardiovascular Magnetic Resonance Imaging and Multidetector CT

Establishing the diagnosis of coronary artery disease (CAD) in a patient
presenting with chest pain remains a challenging task. Patients with low
likelihood of CAD (<10%) according to clinical history may be dismissed without
further testing. The management of patients with intermediate to high
probability is less clear. Coronary angiography (CAG) is an invasive and
expensive procedure, and is considered inappropriate as a first line technique,
except in the very high-risk patients, and non-invasive testing is generally
used to further refine the clinical suspicion of disease. Current clinical
practice using ECG-exercise testing, stress (nuclear) myocardial perfusion
imaging (SPECT), or stress echocardiography leads to a considerable number of
unnecessary referrals for CAG.
Based on local availability and expertise, we have therefore recently adopted a
different and more structured diagnostic strategy, that uses Cardiovascular
Magnetic Resonance imaging (CMR) and multidetector (MD)CT as first line imaging
modalities instead of nuclear techniques, echocardiography or exercise testing.
CMR effectively assesses myocardial perfusion and function in patients with
(suspected) ischemic heart disease. MDCT accurately depicts coronary artery
anatomy and atherosclerotic changes including coronary artery related calcium.
This project primarily aims at evaluating the diagnostic accuracy of the
non-invasive CMR/MDCT work-up by comparison with invasive examinations, and at
the development of an optimal diagnostic algorithm by exploring the sequential
use of both techniques.

Primary objectives:
1. To determine and compare diagnostic accuracy of CMR, MDCT calcium score and
MDCT coronary angiography for the detection of significant CAD, using invasive
coronary angiography as reference standard
2. To develop a screening algorithm (decision tree model) involving the
sequential use of both imaging modalities

Secondary objectives:
1. To calculate and compare the costs relative to diagnostic accuracy for CMR
and MDCT, and for the proposed algorithm
2. To record 1-year clinical outcome, from which pilot results can be referred
to set up a multicenter study to evaluate the prognostic accuracy of the
CMR/MDCT work-up

220 symptomatic patients (30-70) that undergo the CMR/MDCT work-up for
suspected CAD of intermediate likelihood will be invited to participate in the
study. All patients will undergo coronary angiography, either clinically
indicated because of an abnormal work-up (80%) or for study purposes (20%).
Non-invasive and invasive test results will be compared and diagnostic accuracy
of CMR, MDCT-calcium score and MDCT coronary angiography for the detection of
significant CAD will be calculated. Using these results, a decision tree will
be designed for the optimal approach of patients with intermediate likelihood
CAD. From 1-year clinical outcome data pilot results will be referred to set up
a multicenter study to evaluate the prognostic accuracy of the CMR/MDCT
work-up.

For the majority of the study group there are no additional risks involved in
participation. All patients with a negative work-up will also be invited to
undergo coronary angiography (CAG) to assess specificity and negative
predtictive value of the work-up.
Compared to MRI and CT, CAG is associated with higher burden and risk (see also
item E9). However, the likelihood of complications in this patient group
without cardiovascular or renal disease is very low, and acceptable when
weighted against the study goals (establishing diagnostic accuracy of the
work-up and creating a fast and more effective diagnostic trajectory), which
may benefit many future patients.