Pushing the limits: establishing an ultra-low framerate and antiscatter grid-less radiation protocol for left atrial ablations.

Aims: Despite the use of 3D mapping systems and new developments of non-fluoroscopic options, most centres still rely at least in part on fluoroscopy for catheter visualization during catheter ablations. The purpose of this study was to assess the feasibility of using an ultra-low frame rate and antiscatter grid-less radiation protocol during complex left atrial ablations to minimize radiation exposure for the patient and staff. Methods and results: A total of 150 consecutive patients undergoing left atrial ablations in our hospital were included in the analysis. The procedures were performed between January 2015 and November 2016. Of the included patients 75 (50%) underwent ablation before and 75 (50%) after the ultra-low frame rate (reduced from 4 to 2 FPS) and antiscatter grid-less radiation protocol was established. Procedures performed after the dose reduction protocol was established showed a 64% reduction of the dose area product (630.28 ± 550.96 vs. 226.44 ± 277.44 µGym2, P < 0.001), while fluoroscopy duration (14.22 ± 4.47 vs. 13.62 ± 7.11 min, P = 0.066) and procedural duration (1:48 ± 0:28 vs. 1:53 ± 0:34 min, P = 0.525) were not prolonged. Acute procedural success was achieved in all procedures. Two complications occurred before and one complication after the protocol was established. During four procedures, operators decided to re-introduce the antiscatter grid. This was due to impaired visibility in morbidly obese patients (n = 2) or technically difficult transseptal puncture (n = 2).
Conclusion: The use of an ultra low framerate and antiscatter grid-less radiation protocol effectively reduced radiation dose for complex left atrial ablation procedures and lead to very low average patient doses. Reduced image quality did not impair procedural and fluoroscopy duration or acute procedural success.