X‐Ray Dose Reduction in Fluoroscopically Guided Electrophysiology Procedures

Abstract

This study assessed the efficacy of a new dose reduction regime in fluoroscopically guided electrophysiology (EP) procedures, which included diagnostic electrophysiological investigations, radiofrequency ablation, and biventricular pacing. A modified dose regime for fluoroscopy was implemented in one of our cardiac electrophysiology laboratories. The x-ray system was programmed with a hierarchy of three fluoroscopy doses, and therefore image quality and settings. The default (lowest) dose mode was not expected to be suitable for all patient sizes or for the entirety of all procedures. Staff raised the dose level in a stepped manner as and when required to optimize the imaging requirements of the procedure. Phantom studies indicated that the low dose mode provided adequate image quality for visualizing EP catheters, while significantly lowering patient skin dose. In 52 clinical cases, questionnaires were used to assess the subjective clinical image quality. The mean image quality score for the low dose setting was rated between "adequate" and "good." The fluoroscopy dose level was raised from the lowest level for 6% of the total fluoroscopy time. Procedural Dose Area Product (DAP) meter readings were analyzed for patients prior to (n = 85) and after (n = 150) the implementation of the low dose regime and showed an overall reduction in DAP rate of 74%. The hierarchical dose regime proved to be acceptable in routine clinical practice for EP procedures, leading to significant reductions in patient doses.

Reassessment of Radiation Risks from Electrophysiology Procedures Compared to Coronary Angiography

“…The NRPB W4 [6] lists the effective dose (E) for a generic cardiac ablation procedure of between 3 and 21 mSv with a Dose Area Products (DAP) of 30-91 Gy cm 2 . Exposures of this range and order of magnitude are also reported by others [7][8][9][10][11][12] although it is also suggested that exposures well in excess of these levels are possible in more complex studies such as the treatment of Atrial Fibrillation where mean DAP levels as high as 251 Gy cm 2 have been reported [8]. At these levels, the radiation related risks associated with EP studies (particularly ablation procedures) would be well in excess of those quoted for diagnostic CA procedures (3.1-10.6 mSv or 14-60 Gy cm 2 ) [6,13].…”

“…EP can be successfully performed at lower imaging frame rates than CA. The comparatively lower absolute demands for image quality (resolution and contrast) of EP imaging in comparison to CA and cardiac angioplasty also suggests that these procedures can be run at lower detector dose rates [12] (i.e. users can tolerate higher levels of image noise).…”

Improving safety in the electrophysiology laboratory using a simple radiation dose reduction strategy: a study of 1007 radiofrequency ablation procedures

“…Alterations to the fluoroscopy pulse rate or pulse width have been used to reduce radiation in cardiac pacing and in electrophysiology studies including ablations 20. This reduction in temporal resolution has no effect on image quality and in this study no operator requested that the pulse rate be increased after DRM.…”

How to set up and apply reference levels in fluoroscopy at a national level

“…More and more effort is focused on dose-intensive fluoroscopy examinations. At the international level, the results of several investigations of patients' doses have been published in the recent literature [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28]. Since the dose-intensive examinations involving fluoroscopy may result in a significant risk of deterministic effects, notably to the skin, it is recommended that the entrance surface doses be monitored for preventing skin injuries.…”