Limitations
Our study has several limitations. First, this was a retrospective observational study with small sample size. Although the incidence of AT after the Maze procedure was reported to be 5-15%,13the frequency of AT after the Maze procedure is unknown because this study included cases from other facilities. In addition, the types of CS and the Maze procedure,25 such as Maze line and energy sources, varied slightly depending on institutions. Almost half of the cases in this study were treated with CryoMaze2 in our institution, but to determine the exact incidence of AT after unified Maze procedure and characteristics of such AT, prospective multicenter studies are needed.