Early experience with the cryoablation balloon procedure for the treatment of atrial fibrillation by an experienced radiofrequency catheter ablation center
BACKGROUND:Radiofrequency (RF) catheter ablation has provided an effective method for treating drug-refractory symptomatic atrial fibrillation. Recently, a cryoablation balloon approach has also received approval. The purpose of this study was to compare RF catheter ablation to cryoablation for the treatment of atrial fibrillation with respect to safety, immediate efficacy, and effects on procedural and fluoroscopy times. In addition, actual procedural costs were compared. METHODS:This study was approved by the Winthrop University Hospital Institutional Review Board to retrospectively examine cryoablation with the Arctic Front Cardiac CryoAblation balloon catheter (Medtronic, Inc) and compare it to RF catheter ablation for the treatment of drug-refractory symptomatic atrial fibrillation. Patient and procedural characteristics as well as immediate success were compared. Immediate failure was defined as incomplete pulmonary vein isolation of all veins. RESULTS:A total of 124 procedures (62 RFs and 62 cryoablations) were performed from December 2010 through July 2012. The cryoablation procedure took longer to perform than RF (171 Â± 61 minutes vs 126 Â± 49 minutes, respectively; P<.0001). There was no difference in fluoroscopy times between the two groups (29 Â± 20 minutes for RF vs 32 Â± 18 minutes for cryoablation; P=.39). The infusion of protamine following procedures was much more common in the cryoablation group (30 patients vs 2 patients in the RF group; P<.0001). The immediate success rate was 93.5% with RF ablation vs 96.7% with cryoablation (P=NS). There was not a significant difference in complications between the two approaches. The cost for each procedure was $24,391.88 Â± 4826.77 for RF and $31,874.02 Â± 8349.70 for cryoablation (P<.0001). CONCLUSION/CONCLUSIONS:Cryoablation provides an additional and alternative approach to RF ablation for the treatment of symptomatic drug-refractory atrial fibrillation with comparable immediate success and complications. It is synergistic with RF and permits the ability to tackle the entire gamut of atrial fibrillation (ie, paroxysmal and persistent). This study showed no decrease in procedural or fluoroscopy times with our early experience. One significant limitation with cryoablation is the cost. Cryoablation resulted in over $7000 extra cost to the hospital per procedure. The clinical benefits achieved by this additional cost warrant further investigation.
Selective site pacing: rationale and practical application
Although it has become traditional to place permanent pacemaker leads at the right ventricular apex and right atrial appendage, pacing from these locations poorly mimics normal physiology. A growing evidence base shows that right ventricular apical pacing results in ventricular dyssynchrony and various adverse effects. Provocative data from early trials suggest that pacing from alternate sites in the right ventricle--His bundle pacing, para-Hisian pacing, septal right ventricular outflow tract pacing, and right ventricular midseptal pacing--may lead to improved results. Similarly, early data suggest that right atrial pacing near Bachmann's bundle may lead to superior outcomes when compared with pacing from the right atrial appendage. Several large-scale, randomized clinical trials are now under way to establish the future role of selective site pacing.