Left atrial size and abnormal conduction zone
For further analysis, all patients were divided into three groups as follows: normal / mildly enlarged LA group (n=68), moderately enlarged LA group (n=21), and severely enlarged LA group (n=11) according to LA diameter/BSA. Larger LA size was associated with lower global LA voltage (normal/mildly enlarged LA group: 5.8±2.2 mV, moderately enlarged LA group: 5.0±2.1 mV, severely enlarged LA group: 3.2±1.5 mV, P=0.0011). The incidence and number of ACZ did not differ among the three groups. A longer ACZ was significantly associated with a larger LA size (Table 2 , normal/mildly enlarged LA group: 49.4±40.2 mm, moderately enlarged LA group: 62.7±45.6 mm, severely enlarged LA group: 77.8±38.3 mm, P=0.0469).