We enrolled 130 consecutive patients who received CA and bepridil for persistent AF with severe LA enlargement for the first time at Niigata University Medical and Dental Hospital and Niigata Medical Center between 2017 and 2021. All patients were hospitalized for AF. Persistent AF was defined as continuous AF lasting for more than 7 days. We considered an LA volume index >48 ml/m2(as measured by echocardiography) to indicate severe LA enlargement.13