CHICAGO, ILLINOIS. Ablations aimed at curing cardiac arrhythmias are traditionally performed using fluoroscopy to guide catheter placement. This exposes the patient, physician and staff to a not insignificant amount of radiation, especially if the procedure is of long duration, or the patient is obese. In addition to repeated radiation exposure, electrophysiologists doing numerous procedures are also prone to develop spinal complaints from wearing the heavy lead apron necessary to provide radiation protection. Robotic systems have been developed to allow the EP to perform ablation from a remote location and thus avoid radiation exposure; however, the problem of exposure remains in the case of the patient and support staff.
A group of researchers from the Illinois Masonic Medical Center now suggests that catheter ablations for cardiac arrhythmias can safely and effectively be performed without the use of fluoroscopy, i.e. with no radiation exposure at all. Their study involved a group of 60 consecutive patients referred for ablation of various cardiac arrhythmias. Twenty-two (37%) had atrial fibrillation, 10 (17%) atrial flutter, 9 (15% atrial tachycardia, 16 (27% atrioventricular tachycardia, and 3 (5%) had ventricular tachycardia. All patients underwent catheter ablation by the same experienced operator using intracardiac electrograms (IE), an electroanatomic mapping system (EnSite NavX), and intracardiac echocardiography (ICE). Conscious sedation was used in all procedures except in the case of atrial fibrillation (AF) where general anesthesia was employed. Transesophageal echocardiography (TEE) was performed on all AF patients, except in those presenting with sinus rhythm and a CHADS2 score of 0 or 1.
Atrial fibrillation patients underwent a pulmonary vein isolation procedure with additional lesions as required to achieve an acute success rate of 100% (all patients were in normal sinus rhythm at completion of procedure). The total average procedure time was 5 hours. The procedural outcome for the 60 patients who had been ablated without fluoroscopy was compared to that of 60 matched patients who had previously been ablated with the aid of fluoroscopy, combined with electroanatomic mapping and ICE guidance (in some cases). In both patient groups acute success was 100% for AF and procedure time was not significantly different at about 5 hours. Average fluoroscopy time in the fluoroscopy group was 33 minutes.
The researchers conclude that catheter ablations for a variety of cardiac arrhythmias can be safely and effectively achieved without the aid of fluoroscopy.
Razminia, M, et al. Nonfluoroscopic catheter ablation of cardiac arrhythmias in adults. Journal of Cardiovascular Electrophysiology, Vol. 23, October 2012, pp. 1078-86
Editor's comments: Although long-term success rates are not available for the patients participating in the study, the acute results certainly look promising. It is to be hoped that the nonfluoroscopy approach will be thoroughly evaluated in major ablation centers.