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potential concern in younger subjects. It is neither completely sensitive nor completely specific but it is
non-invasive. From the certificatory point of view, it may be indicated as the investigation of election
when, for example, evidence of satisfactory revascularization is being sought following coronary
surgery/angioplasty/stenting. The JAA now accepts the investigation for this purpose, provided there is
also a coronary angiogram available in relation to the index event. As the primary investigation in the
presence of an abnormal exercise ECG, it will give an indication of prognosis, but only indirect evidence
on the coronary anatomy. This may be inadequate from the clinical point of view. The recommendation to
perform the investigation depends on both the clinical and the certificatory situation.
Cardiovascular Magnetic Resonance / Magnetic Resonance Imaging
Cardiovascular Magnetic Resonance (CMR) is safe, bears no radiation burden and is non-invasive. It is
capable of defining antomy, function, flow, tissue perfusion and the anatomy of the larger coronary
vessels. It has an established role in the investgation of the the cardiomyopathies and in the definition of
congenital heart disease. It is also useful in the assesment of the ischaemically damaged ventricle, and the
great vessels. It is for these indications that a Magnetic Resonance Image (MRI) scan may helpful in
establishing a fit assessment in certain aircrew.
Electron-beam Computerized Tomography and Multi-Detector Computed Tomography Coronary
Angiography
Electron-Beam Computerized Tomography (EBCT) is a comparatively new radiographic technique which
detects calcium in the coronary arteries, the Agatston score1 correlating with the presence of calcium in
the wall of the coronary artery, and, by extrapolation, atheromatous disease. Its value in determining
prognosis is under evaluation. At a recent American College of Cardiology consensus conference, a 70
per cent predictive accuracy for obstructive disease was identified for the technique but with lower
specificity. It is not required for regulatory purposes but may prove useful once there are more data on its
prognostic power. Like exercise ECG, it is likely to have a high negative predictive accuracy in subjects
with a low probability of coronary artery disease. If an aircrew member undergoes the investigation for
whatever reason, and the result suggests the possibility of coronary artery disease, further investigation is
indicated using available techniques.
Electron-beam computerized tomography has a radiation burden about half that of coronary angiography
but is being supplanted by Multi-Detector Computed Tomography Coronary Angiography (MDCTCA) in
the non-invasive assessment of the coronary arteries. The radiation burden of the latter is the same as
thallium MPI and at least twice that of coronary angiography. It has not yet replaced coronary
angiography in the pre-intervention assessment of coronary artery disease,
Coronary angiography
Coronary angiography has long been regarded as the gold standard in the assessment of prognosis in
coronary artery disease. If other tests have not been reassuringly negative during an assessment, this
investigation may be warranted and certification may not be possible without it. It carries a very small
risk of death — less than one in 5000 in healthy individuals (such as an aircrew population) with a
slightly higher risk of vascular damage to the vessel of entry or due to stripping of the intima of the
coronary artery. The latter may provoke a myocardial infarction. In private flyers, the procedure is
difficult to justify for certificatory purposes alone, except at the insistence of the individual.
1 Agaston score: a score for quantification of coronary calcification, based on the size and density of calcified
plaques on CT. Named after Dr. Arthur Agatston, contemporary American cardiologist.
ICAO Preliminary Unedited Version — October 2008 III-1-12
There is an assumption that a normal coronary angiogram showing no evidence of obstructive coronary
artery disease, together with a normal contrast ventriculogram, bears a low risk of future event. From the
certificatory point of view this is probably correct, but there remains a small group of people who have
abnormal exercise ECG responses without clinical or other explanation. In these people, the tendency to
regard them as fit, based only on their coronary anatomy, should be regarded with caution as they may
subsequently demonstrate a myocardial abnormality. Follow-up therefore is advisable.
Specific problems in cardiology and cardiovascular medicine
Vascular risk factors
Vascular risk factors are those inherited or acquired (often metabolic) abnormalities, or lifestyle patterns,
　
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