Patient background characteristics
A total of 74 patients were matched and enrolled in this study. An EC between the right-sided PV and RA was observed in 23 patients (31%, EC-positive group) but not in the remaining 51 patients (69%, EC-negative group) (Figure 2). There were no differences in patient characteristics between the groups, except the EC-positive group had a smaller LA diameter, lower CHADS2 score, and smaller body mass index than that in the EC-negative group (Table 1).