Objective The objective was to attempt to rule out whether high-pitch spiral acquisition dual-source computed tomography coronary angiography (CTCA) can be performed in patients with atrial fi-brillation at low dose. Methods Ten patients with atrial fibrillation who were admitted for a first diagnostic coronary angiogram were screened for participation. All patients underwent dual-source CT. Patients were per-formed CTCA using the prospectively ECG-gated high-pitch mode and retrospective ECG gating spiral acqui-sition respectively with their permissions. The start phase for image acquisition of the most cranial slice was selected at 20% -30% of the R-R interval in all patients. Results Image qualities of prospectively ECG-ga-ted high-pitch mode were rated as being excellent in 7 cases of all the patients and only 3 cases image quali-ties were graded score 2. By using retrospective ECG gating spiral acquisition mode, non-diagnostic image quality (score 3) occurred in 4 patients which were observed in RCA and 1 patient in LCX. The estimated radiation dose ranges from 0. 68 to 1. 887 mSv in flash mode and the radiation dose of spiral mode were very high ranging from 14. 92 to 29. 308 mSv. Conclusions Our case series suggest that patients with atrial fibril-lation rhythm can be performed CTCA with high-pitch spiral acquisition mode. 20% -30% of the RR interval window for data acquisition for high-pitch dual-source CTCA may probably obtain good image quality with low doses.