Background

Transcatheter mitral valve repair is an increasingly used therapy for mitral regurgitation which requires fluoroscopic guidance. Limiting radiation exposure during lengthy procedures is important for both patient and operator safety. This study aimed to investigate radiation dose during contemporary use of MitraClip implantation and the effects of a dose reduction program.

Methods

A total of 115 patients who underwent MitraClip implantation were prospectively enrolled in a single-center observational study. During the inclusion period, our institution adopted a radiation dose reduction program, comprising lowering of fluoroscopy pulse rate and image target dose. The first 58 patients were treated with conventional fluoroscopy settings, while the following 57 patients underwent the procedure with the newly implemented low dose protocol.

Results

Radiation dose area product significantly decreased after introduction of the low dose protocol (693 [366-1231] vs. 2265 [1517-3914] cGy·cm², p<0.001). After correcting for fluoroscopy time, gender and body mass index, the low dose protocol emerged as a strong negative predictor of radiation dose (p<0.001), reducing dose area product by 64% (95% CI [57, 70]). Device time, device success, and procedural safety did not differ between the normal dose and low dose group. Furthermore, the low dose protocol was not associated with an increased incidence of a combined endpoint consisting of death, repeat intervention, or heart surgery during twelve months follow-up.


Figure 1: Dose area product (A), fluoroscopy time (B) and dose area product per fluoroscopy time (C) during transcatheter mitral valve repair, stratified by fluoroscopy protocol. Bars show median with interquartile range. Dose area product is presented on a logarithmic scale.

Conclusion

Reduction of radiation exposure during transcatheter mitral valve repair by 64% is feasible without affecting procedural success or safety.