Cardiovascular disease is the leading cause of mortality and morbidity in industrialised countries. Traditional risk factor based scores have predictive value to identify patients at low, intermediate or high risk. However, these scores may not be very specific, and coronary plaque imaging may be useful to more precisely identify patient’s risk.
Large studies have shown that the coronary calcium score has incremental predictive value over and beyond traditional risk factors, and it is now recommended in individuals at intermediate risk. In these individuas, the calcium score may reclassify patients with a low calcium score to a low risk group, and those with a high calcium score to a high-risk group, and subsequent intensive risk factor modification, even including pharmacological treatment.
64-Slice CT coronary angiography has a high diagnostic performance and in particular, is highly reliable to rule out coronary artery disease. It is now recommended for use in symptomatic patients at intermediate pre-test risk of CAD, where a negative CT scan reliably rules out the presence of CAD and prevents patients from referral to invasive coronary angiography. 64-slide CT coronary angiography is also useful to rule out obstructive disease in venous and arterial bypass grafts, but evaluation of stenotic disease in native coronary arteries in these patients is problematic (small vessels, severely calcified) and still requires invasive coronary angiography.
In-stent restenosis evaluation continues to be difficult with CT due to the extreme blooming effect of the stent material. In larger stents (>3.0mm diameter), CT may be useful, however smaller stents cannot be evaluated by CT.
A significant question is whether we should use a technique that evaluates anatomy or a technique that evaluates the function (flow limitation) of the obstructive disease. In asymptomatic individuals, calcium screening is useful. Coronary calcium is a hallmark of coronary artery disease, and there is a linear relation between the magnitude of the calcium score and the rate of adverse cardiac events. It is of note that perfusion imaging cannot detect early coronary artery disease.
CT coronary angiography may be the first option in symptomatic patients at intermediate pre-test risk, and symptomatic patients at high pre-test risk may be referred for a perfusion imaging test, and if moderate to severe ischemia is present, may be referred for invasive coronary angiography and revascularisation.
Notes to editor
This congress report accompanies a presentation given at the ESC Congress 2008. Written by the author himself/herself, this report does not necessarily reflect the opinion of the European Society of Cardiology.