AUTHOR=Jin He , Feng Mingjun , Du Xianfeng , Wang Binhao , Yu Yibo , Fu Guohua , Shen Caijie , Chu Huimin TITLE=A novel method using body surface steel ball as a reference scale to measure the left atrial appendage for optimal selection of Watchman device JOURNAL=Frontiers in Cardiovascular Medicine VOLUME=12 YEAR=2025 URL=https://www.frontiersin.org/journals/cardiovascular-medicine/articles/10.3389/fcvm.2025.1464567 DOI=10.3389/fcvm.2025.1464567 ISSN=2297-055X