SVC area
Figure 2B shows a comparison of the SVC area before and after the
ablation process. The mean SVC area at baseline was 2.50 ± 0.94
cm2. By contrast, the SVC area after the ablation was
reduced to 2.19 ± 0.82 cm2. Trivial (0–25%), mild
(25–50%), moderate (50–75%) stenoses were observed in 73 (78%), 13
(14%), and 5 (5%) patients, respectively. No severe stenosis
(dimensional reduction >75%) was observed in this study.
The relevant application times are plotted in Figure 3. No significant
differences were noted among the three groups, and the degree of SVC
narrowing was not found to be significantly correlated with the
application time.
Eight patients associated with 18 mild and moderate narrowing cases
(1.56± 0.42 cm2) were followed further at 20 ± 4.2
months after the ablation process, and the SVC area were estimated
again. The mean SVC area shown in Figure 4 was 1.80 ± 0.57
cm2. This is slightly larger compared to the value
recorded four months after the ablation process. SVC narrowing did not
progress with the exception of two cases that did not develop
symptomatic severe stenosis.