Safety of Ventricular Arrhythmia Radiofrequency Ablation with Half-Normal Saline Irrigation.

BACKGROUND: Failure of radiofrequency (RF) ablation of ventricular arrhythmias is often due to inadequate lesion size. Irrigated radiofrequency ablation with half-normal saline (HNS) has the potential to increase lesion size and reduce sodium delivery to the patient if the same volume of RF irrgant were used for NS and HNS, but could increase risks related to steam pops and lesion size.

AIMS: To assess peri-procedural complications and acute ablation outcome of ventricular arrhythmias ablation with HNS.

METHODS: Prospective assessment of outcomes was performed in 1,024 endocardial and/or epicardial radiofrequency ablation procedures in 935 consecutive patients (median age 64 years, 71.2% men, 73.4% cardiomyopathy, 47.2% sustained ventricular tachycardia). HNS was selected at the discretion of the treating physician. RF ablation power was generally titrated to a ≤ 15 Ohm impedance fall with intracardiac echocardiography monitoring.

RESULTS: HNS was used in 900 (87.9%) and normal saline in 124 (12.1%) procedures. Any adverse event within 30 days occurred in 13.0% of patients treated with HNS RF ablation including 4 (0.4%) strokes/transient ischemic attacks and 34 (3.8%) pericardial effusions requiring treatment (most related to epicardial access). Two steam pops with perforation required surgical repair (0.2%). Patients who received normal saline irrigation had less severe disease and arrhythmias. In multivariable models, adverse events, and acute success of the procedure were not related to the type of irrigation.

CONCLUSION: HNS irrigation RF ablation with power guided by impedance fall and intracardiac echocardiography has an acceptable rate of complications and acute ablation success while administering half of the saline load expected for normal saline irrigation.