No differences existed between the two groups in terms of clinical background and various parameters related to the catheter ablation , including RF delivery time and number of RF deliveries at an esophageal temperature of > 42 C. Esophageal lesions , such as esophagitis and esophageal ulcers , occurred in 10/50 ( 20 % ) and 15/50 ( 30 % ) patients in the multi-thermocouple and deflectable temperature probe groups , respectively ( P = 0.25 ) .