As
the first imaging modality of the living human body, X-ray fluoroscopic imaging
has been the most important technical tool in modern medicine (Roentgen). It
allowed one to see the inside of the body and, after contrast injection, even of
soft tissues like the beating heart. To date, most of
interventional procedures in cardiology are carried out under fluoroscopic
imaging guidance. Besides other peri-interventional risks, radiation exposure
should be considered for its stochastic (inducing malignancy) and deterministic
effects on health (tissue reactions like erythema, hair loss and cataracts).
Due
to increased interventional procedures and imaging studies in the last decades,
patients are being exposed to a substantial amount of radiation over their
lifetime. Some procedures like catheter ablation of atrial fibrillation
frequently requires cardiac computed tomography (CT) scan before the
intervention and more than one ablation procedure, thereby adding a substantial
amount of radiation.
On an average, a
complex cardiac radiofrequency ablation corresponds to 750 chest X-rays (range
100–2850). Recently, attention
has been applied to the radiation exposure of the catheter lab staff who expose
themselves professionally. Being close to the patient during an interventional
procedure, the first hand operator is exposed to scattered radiation, whilst other
health care professionals are better protected by their position at a greater
distance to the radiation source and the patient itself.
Besides
the associated X-ray exposure, the main limitation of fluoroscopy is that in
complex arrhythmias fluoroscopy only provides two-dimensional (2D)
representations of three dimensional (3D) anatomical structures as potentials
targets for ablation. With the evolution of technology, new non fluoroscopic 3D
mapping systems from the late 1990s have been an alternative to fluoroscopy
alone in electrophysiology world. Infact constructing a virtual real time 3D
map, catheter navigation is facilitated while minimizing or eliminating
fluoroscopy exposure. New software upgrades to non fluoroscopic 3D mapping have
resulted in very detailed cardiac chambers, potentially eliminating
pre-procedure CT imaging.
In this
article we analized the radiation risk from cardiovascular imaging to both
patients and medical staff and discusses how customize the X-ray system and how
to implement shielding measures in the cath lab. Finally, we reviewed the most recent
developments and the latest findings in catheter navigation and 3D
electronatomical mapping systems that may help to reduce patient and operator
exposure.
Credits: Michela Casella; Eleonora Russo; Francesca Pizzamiglio; Sergio Conti; Ghaliah Al-Mohani; Daniele Colombo; Victor Casula; Yuri D’Alessandra; Viviana Biagioli; Corrado Carbucicchio; Stefania Riva; Gaetano Fassini; Massimo Moltrasio; Fabrizio Tundo; Martina Zucchetti; Benedetta Majocchi; Vittoria Marino; Giovanni Forleo; Pasquale Santangeli; Luigi Di Biase; Antonio Dello Russo; Andrea Natale; Claudio Tondo