Abstract
Background Optimal occlusion of pulmonary vein (PV) is
essential for atrial fibrillation (AF) cryoballoon ablation (CBA). The
aim of the study was to investigate the performance of two different
tools for the assessment of PV occlusion with a novel navigation system
in CBA procedure.
Methods In consecutive patients with paroxysmal AF who
underwent CBA procedure with the guidance of the novel 3-dimentional
mapping system, the baseline tool, injection tool and pulmonary
venography were all employed to assess the degree of PV occlusion, and
the corresponding cryoablation parameters were recorded.
Results In 23 patients (mean age 60.0 + 13.9 years,
56.5% male), a total of 149 attempts of occlusion and 122 cryoablations
in 92 PVs were performed. Using pulmonary venography as the gold
standard, the overall sensitivity, specificity of the baseline tool was
96.7% (95% CI 90.0% - 99.1%), and 40.5% (95% CI 26.0% - 56.7%),
respectively, while the corresponding value of the injection tool was
69.6% (95% CI 59.7% - 78.1%), and 100.0% (95% CI 90.6% -
100.0%), respectively. Cryoablation with optimal occlusion showed lower
nadir temperature (baseline tool: -44.3 + 8.4 ℃ vs -35.1 +6.5 ℃, p < 0.001; injection tool: -46.7 + 6.4 ℃ vs
-38.3 + 9.2 ℃, p < 0.001) and longer total thaw time
(baseline tool: 53.3 + 17.0 s vs 38.2 + 14.9 s, p = 0.003;
injection tool: 58.5 + 15.5 s vs 41.7 + 15.2 s, p
< 0.001) compared with those without.
Conclusions Both tools were able to accurately assess the
degree of PV occlusion and predict the acute cryoablation effect, with
the baseline tool being more sensitive and the injection tool more
specific.
Key words : atrial fibrillation, cryoballoon, catheter ablation,
pulmonary vein occlusion, 3-dimensional mapping