Introduction
During the past decades, catheter ablation has been an established
curative treatment for atrial fibrillation (AF), with pulmonary vein
isolation (PVI) as its cornerstone1, 2. Cryoballoon
ablation (CBA) is a promising tool for achieving PVI, and its safety and
efficacy have been extensively investigated3-6. In CBA
procedure, optimal occlusion of the inflated balloon to each pulmonary
vein (PV) antrum is essential for achieving adequate tissue lesions and
durable PVI. To date, PV occlusion is assessed by contrast medium
injection through the central lumen of the cryoballoon (CB), which
increases contrast dose and radiation exposure.
The KODEX-EPD system (EPD Solutions, a Philips Company) is a novel
3-dimentional navigation system7, 8, which was shown
to be feasible to reconstruct high-resolution left atrial (LA) images,
and to facilitate CBA procedure9. In addition, the
occlusion verification software integrated in the system has recently
been demonstrated to provide accurate and real-time information of
occlusion degree of CB10, 11, thus significantly
reduce contrast use and radiation exposure in CBA
procedure12. In the latest version of this system,
there are two tools, the baseline tool and the injection tool, available
to facilitate the process of occlusion assessment. However, the accuracy
of the two tools has not been systematically evaluated.
The purpose of the present study was to investigate the performance of
the two different tools for PV occlusion assessment with KODEX-EPD
mapping system in CBA procedure for AF.