We have read with great interest the manuscript to be published in your journal by Meyer et al entitled: “Impact of Coronary Calcium Score on the Prevalence of Coronary Artery Stenosis on Dual Source CT Coronary Angiography in Caucasian Patients with an Intermediate Risk.” It concludes that because significant coronary artery stenosis is extremely unlikely in Caucasian patients with an intermediate cardiovascular risk and negative calcium score, radiation-free tests should be considered for differential diagnosis of chest pain in these patients . We think that there are two points of discussion and special interest about this matter.
First, in symptomatic patients with chest pain and intermediate cardiovascular risk, computed tomography angiography (cCTA) should not be the first diagnosis tool. In fact, it is recognized as an alternative when ischemic stress tests are not possible or inconclusive; therefore, as the authors conclude and we completely agree, other tests should be considered in these patients but preferably before or instead of cCTA. Otherwise, it is well known that when the technique and patient selection are appropriate, cardiac CT is a valuable diagnostic tool, particularly for patients with a low to intermediate pretest probability of coronary artery disease . Another relevant point is the attitude of symptomatic patients with intermediate probability of coronary artery disease and negative calcium score. Recently, different series have been published about this matter. Morita et al have found an incidence of significative stenosis of 2.4% in these kinds of patients, especially in elderly males . Another study by Chen et al has concluded that plaques are present in a significant proportion of patients with a zero calcium score . So although low, the probability of significative coronary artery disease in this population of patients exists; therefore, the absence of calcium must not preclude the absence of significative soft plaques. What should we do then? As we have previously mentioned, we think that functional tests to detect ischemia must be the first option if they have not been previously undertaken. In cases in which these tests were not possible or not conclusive in symptomatic patients with intermediate probability and zero score, proceeding with noninvasive coronary angiography after calcium score could be a good diagnostic option.
References
1. Meyer M., Henzler T., Fink C., et. al.: Impact of coronary calcium score on the prevalence of coronary artery stenosis on dual source CT coronary angiography in Caucasian patients with an intermediate risk. Acad Radiol 2012; 19: pp. 1316-1323.
2. Wallis A., Manghat N., Hamilton M.: The role of coronary CT in the assessment and diagnosis of patients with chest pain. Clin Med 2012; 12: pp. 222-229.
3. Morita H., Fujimoto S., Kondo T., et. al.: Prevalence of computed tomographic angiography-verified high-risk plaques and significant luminal stenosis in patients with zero coronary calcium score. Int J Cardiol 2012; 12: pp. 272-278.
4. Chen C.K., Juo Y.S., Liu C.A., et. al.: Frequency and risk factors associated with atherosclerotic plaques in patients with zero coronary artery calcium score. J Chin Med Assoc 2012; 75: pp. 10-15.