LAUSR

BACKGROUND To investigate the anatomical features related to the failure of cryoballoon (CB) ablation for atrial fibrillation (AF) on pre-procedural CT images. METHODS We retrospectively analyzed CT images of 100 patients with AF who had undergone a first CB ablation at our institution between June 2016 and April 2017. We measured the angle, short- and long axis length, and the area and ovality of 4 major pulmonary vein (PV) ostium on CT images. We performed logistic regression analysis to analyze the anatomical features related to the failure (incomplete CB ablation) of PV isolation. We also performed a receiver-operating characteristic (ROC) curve analysis to identify an appropriate cut-off value for anatomical features significantly associated with incomplete CB ablation. RESULTS We analyzed 400 PVs in 100 patients [aged 64 (range, 27-82) years, 59% male]. The rate of incomplete CB ablation was significantly higher for right-than left-sided PVs (p < 0.001). The anatomical feature significantly associated with incomplete CB ablation was the angle at the right inferior PV (RIPV) (AOR: 1.17; 95% CI: 1.09-1.27, p < 0.001) and the right superior PV (RSPV) (AOR: 1.12; 95% CI: 1.01-1.23; p = 0.014). In the ROC analysis, the optimal cut-off value for RIPV and RSPV angle to discriminate an incomplete CB ablation were 40.1° and 79.7°, respectively. CONCLUSION Our findings may help to select the appropriate ablation strategy to treat patients with AF. We show that the angle is an anatomical feature significantly related to failed CB ablation.