Use of low-dose adaptive sequence scan of dual-source CT in coronary angiography for arrhythmia: An preliminary study

Objective 　To investigate the application of low-dose adaptive sequence scan of dual-source CT in coronary angiography of patients with arrhythmia, and evaluate its diagnostic accuracy. Methods 　One hundred and thirty-four patients with arrhythmia undergoing dual-source CT coronary angiography (CTA) were divided into 2 groups according to the scan mode: patients in group A underwent retrospective ECG-gating helical scanning (n=78); patients in group B received adaptive sequence scanning (n=56). The sensitivity, specificity, and positive and negative predictive values of dual-source CTA were determined by using conventional coronary angiography as the reference standard. The significance of difference between the two groups was analyzed, and the respective radiation dose was also compared. Results 　The overall sensitivity, specificity, and positive and negative predictive values was 97.0%, 98.5%, 87.4% and 99.7%, respectively in group A, and 97.0%, 98.8%, 88.9% and 99.7%, respectively, in group B. No statistical difference was found between two groups (P>0.05). The average effective radiation dose was 12.0±3.6mSv in group A, which was significantly higher than that in group B (3.1±0.7mSv, Z=－9.826, P=0.00). Conclusion 　Adaptive sequence scan combined with the absolute phase reconstruction in dual-source CT coronary angiography is feasible in patients with arrhythmia in providing good image quality and diagnostic accuracy at a low effective radiation dose.