Abstract 3085: Non-Invasive Evaluation with Multi-Slice Computed Tomography in Suspected Acute Coronary Syndrome: Plaque Composition on MSCT versus Coronary Calcium Score
Introduction: The absence of coronary calcium during coronary calcium scoring (CS) has been proposed to allow rule-out of significant coronary artery disease (CAD). However, data in patients presenting with suspected acute coronary syndrome (ACS) are scarce and contrast-enhanced coronary angiography may be preferred. The purpose of the study was to evaluate the atherosclerotic plaque burden and morphology as determined by 64-slice Multi-slice Computed Tomography (MSCT) coronary angiography in relation to the CS in patients presenting with suspected ACS.
Methods: In 40 consecutive patients (57±11 years, 26 men) presenting with suspected ACS, non-invasive coronary angiography with 64-slice MSCT in combination with coronary calcium scoring was performed prior to conventional invasive coronary angiography. MSCT angiograms were evaluated for
the presence or absence of coronary atherosclerotic plaque and the presence or absence of obstructive (≥50% luminal narrowing) CAD. In addition, plaque type (calcified, non-calcified or a combination) was determined, and findings were related to the CS score.
Results: In 38 patients CAD was observed, of whom 10 patients had non-obstructive, and 28 patients had obstructive CAD, confirmed by conventional coronary angiography in all patients. In patients with CAD, 39% of the plaques were non-calcified, 47% was mixed and 14% were calcified plaques. Based on the Agatston technique, coronary calcium was detected in 27 patients (67%) of whom 10 (37%) >400. In 33% of the patients, no coronary calcium was observed. In only 2 of 13 (15%) patients without coronary calcium, no coronary atherosclerotic plaques were detected. In contrast, in 38% of the patients without coronary calcium, MSCT did reveal obstructive CAD.
Conclusion: In patients presenting with acute chest pain, non-calcified plaques are highly prevalent. As a result, the absence of coronary calcium does not exclude the presence of atherosclerosis or even obstructive CAD. Accordingly, MSCT coronary angiography may be preferred in this setting.