Dual-source coronary computed tomography angiography in patients with atrial fibrillation: initial experience

Background: Patients with atrial fibrillation (AF) are generally excluded from coronary CT angiography (CCTA) studies because of motion artifact resulting from irregular rhythm. The 83-millisecond temporal resolution of the dual-source CT (DSCT) may be sufficient to allow CCTA in patients with AF. Objective: We examined the feasibility of DSCT in patients with AF referred for CCTA. Methods: We compared results of CCTA with DSCT in 24 consecutive patients with AF with 119 control patients in sinus rhythm. Standard relative-delay phase reconstruction (40%-80% of cardiac cycle) was used, with additional absolute delay reconstruction performed when indicated. Image quality was scored both subjectively and objectively. Results: Patients with AF were older (68.5 ± 14.0 years versus 62.5 ± 12.1 years; P = 0.03). Maximum heart rate during injection was 102.5 ± 30.4 beats/min and 70.8 ± 16.6 beats/min in the AF and control groups, respectively (P < 0.01). Mean (±SD) Agatston score was 321 ± 366 (range, 0-1158) and 361 ± 743 (range, 0-3948) in the AF and control groups, respectively (P = 0.8). No difference was observed in the proportion of uninterpretable segments between the 2 groups, 7 (2%) in the AF group and 12 (1%) in the control group (P = NS). Two (8%) of 24 studies in the AF group and 12 (10%) of 119 studies in the control group were nondiagnostic (P = NS). Image quality was good or excellent in 13 (54%) of 21 AF cases compared with 94 (79%) of 119 control cases (P = 0.01). Absolute delay reconstruction was needed in 9 (38%) of 24 AF cases. Conclusions: These preliminary data show that interpretable CCTA data can be obtained in patients with AF using DSCT. The need for absolute delay reconstruction is common.