Comparison of the radiation dose between dual-acquisition coronary computed tomography angiography and coronary angiography for coronary spasm

Abstract

Background Coronary computed tomography angiography (CCTA) is an imaging technique which can be used to evaluate and diagnose coronary artery stenosis. Dual-acquisition CCTA (DA-CCTA) with additional nitrate infusion is a promising alternative noninvasive diagnostic tool, as conventional CCTA has limitations in the diagnosis of variant angina compared to conventional angiographic coronary spasm tests. However, DA-CCTA may pose a potential risk due to radiation exposure. We compared the radiation dose between DA-CCTA and the coronary angiographic spasm provocation test. Methods Patients with clinically suspected variant angina at a single hospital between March 2013 and October 2018 were screened and underwent DA-CCTA or a coronary angiographic spasm provocation test. The effective radiation dose required for each approach was compared. Results In total, 211 suspected variant angina patients underwent DA-CCTA or the coronary angiographic spasm provocation test. Of these, 49 patients (mean age, 59.8 years; 67.3% men) received DA-CCTA and 162 patients (mean age, 60.5 years; 66.2% men) received a coronary angiographic spasm provocation test. There was meaningful difference in the effective radiation dose, with a median dose of 5.1 mSv (interquartile range [IQR], 4.1–9.2 mSv) required for DA-CCTA and a median dose of 10.9 mSv (IQR, 8.4–15.2 mSv) for the coronary angiographic spasm provocation test (p<0.001). Conclusion DA-CCTA showed a significantly lower effective radiation dose than the coronary angiographic spasm provocation test required to diagnose variant angina.

Keywords

• computed tomography
• coronary angiography
• coronary vasospasm
• radiation dosage