Value of triple rule out 320-detector-row CT angiography in acute atypical chest pain

Objective: To evaluate triple rule-out 320-detector-row CT angiography in patients with acute atypical chest pain. Methods: 79 consecutive patients with acute atypical chest pain underwent triple rule-out 320-detector-row CT angiography. Volume data were acquired in 3 phases after dual flow-rate contrast injection in the cranial-to-caudal direction. The pulmonary and coronary arterial and thoracic aortic attenuation values were measured. Image quality and streak artifacts from the right heart were evaluated. The sensitivity, specificity, positive predictive value, negative predictive value, and agreement rate for demonstrating 50% or greater coronary artery stenosis were calculated in comparison with conventional coronary angiography. Results: The mean attenuation values of pulmonary arteries (370.35 ± 101.34 HU), coronary arteries (396.37 ± 83.54 HU) and thoracic aorta (383.56 ± 68.76 HU) were above the diagnostic threshold of 250 HU. Of 1069 coronary segments, 801 (95.69%) were evaluable with severe streak artifacts in 2.53% (2/79). Findings included pulmonary embolism(13), aortic dissection (9), aortic intramural hematoma (2), penetrating aortic ulcer (3), thoracic aneurysm (2), and coronary artery atherosclerosis (17) including 7 patients with significant lumen stenosis ≥50%. There was high agreement (96.88%) of coronary artery assessment compared to conventional coronary angiography with 90.91% sensitivity, 97.65% specificity, 83.33% positive predictive value, and 98.81% negative predictive value. Conclusion: Triple rule-out CT angiography with 320-detector-row CT can rapidly exclude fatal causes of acute atypical chest pain in combined evaluation of pulmonary artery, thoracic aorta,and coronary artery. (authors)