Site localization and characterization of pain during radiofrequency ablation of the pulmonary veins.

BACKGROUND

Characteristics of radiofrequency (RF) lesions producing pain with an 8-mm catheter during pulmonary vein (PV) ablation have not been prospectively studied.

METHODS

We studied 46 (30 men, age 56 +/- 10 years) patients with AF who underwent RF ablation of PVs. PV isolation was achieved by using an 8F, 8-mm Biosense ablation catheter (Biosense Webster, Diamond Bar, CA, USA) guided by intracardiac echocardiography (ICE). An electroanatomic map was used to document the location of all RF lesions and the time; PV location and maximum temperature of every lesion were recorded. Location of the esophagus was determined by magnetic resonance imaging prior to the procedure and by both ICE and barium swallows during procedure.

RESULT

A total of 1,448 (33 +/- 12) RF lesions were delivered to 180 veins. Thirty-nine patients (85%) had at least one lesion associated with pain (mean: 8 +/- 5 lesions) during ablation. The RF generator setting during lesions resulting in pain sensation was 48.6 +/- 7.0 Watts and 51.5 +/- 2.9 degrees C. Maximum temperature attained at the time of pain sensation was 45.7 +/- 4.2 degrees C. By logistic regression analysis the left superior PV (OR 1.54, CI 1.06-2.24, LS vs RI, P < 0.05) and left inferior PV (OR 2.74, CI 1.79-4.19, LI vs RI, P < 0.001) location were both positively correlated with the production of pain. The location of lesions associated with pain was not near the esophagus during any of the pain-producing lesions.

CONCLUSION

Pain sensation is relatively common during RF ablation of PVs. There was no correlation between pain and the location of esophagus. Pain was more common during RF ablation of left inferior and left superior PVs.