Faculty Bibliography

Background: Unfavorable outcomes observed with stepwise linear ablation of non-paroxysmal AF (NPAF) in large clinical trials utilizing ablation catheters without contact-force sensing (CFS) may be attributable to pro-arrhythmic effects of incomplete ablation lines. The optimal ablation strategy for catheter ablation of NPAF using a contact force sensing radiofrequency (RF) ablation catheter remains unclear. Objective: To compare catheter ablation outcomes of stepwise linear ablation to left atrial (LA) posterior wall isolation in patients undergoing NPAF ablation using a CFS RF ablation catheter. Methods: We performed pulmonary vein antral isolation (PVAI) followed by isolation of the LA posterior wall in 80 consecutive patients undergoing first-time NPAF ablation between November 2015 and March 2016 (Group 1) and compared clinical outcomes to those of 112 consecutive patients who underwent PVAI followed by step-wise linear ablation for NPAF between May 2014 and November 2015 (Group 2). All ablation procedures were performed using the Carto 3 mapping system and SmartTouch RF ablation catheter (Biosense Webster, Inc.). Arrhythmia recurrence was assessed using 2-week event monitors at 3-month intervals. Arrhythmia-free survival at 12 months was estimated using the Kaplan-Meier method. Results: Baseline characteristics of Group 1 and Group 2 were similar. At 12 months follow-up, arrhythmia-free survival was significantly greater in Group 1 patients compared with Group 2 (81.9% vs. 67.5%, respectively; p=0.0318). There was no significant difference in survival free from AF between group 1 and group 2 (89% vs. 84.1%, respectively; p=0.3431), however group 1 patients developed significantly fewer post-ablation atrial tachycardias (AT) than group 2 patients (8.1% vs 30.1%, respectively; p<0.001). Conclusion: Among patients undergoing NPAF ablation using a contact force sensing RF ablation catheter, LA posterior wall isolation resulted in fewer recurrent atrial arrhythmias than a stepwise linear approach. The reduction in recurrent atrial arrhythmias is driven primarily by a reduction in recurrent AT

Introduction: Large clinical trials have recently demonstrated stepwise linear ablation for non-paroxysmal atrial fibrillation (NPAF) to be inferior to pulmonary vein isolation alone. It is unknown whether the unfavorable outcomes observed in these trials can be attributed to the pro-arrhythmic effects of incomplete ablation lines. We hypothesized that improved lesion quality related to use of contact-force sensing (CFS) ablation catheters would improve procedural outcomes. Methods: We prospectively analyzed procedural outcomes of 74 consecutive patients with NPAF undergoing first-time radiofrequency catheter ablation with a CFS catheter (Smart Touch, Biosense Webster) using a step-wise approach (Group 1). The clinical outcomes of these patients were compared with 74 consecutive patients with NPAF who underwent catheter ablation between September 2013 and June 2014 with a non-contact force sense radiofrequency ablation catheter (Group 2) at a single tertiary care medical center. Arrhythmia recurrence was assessed using 2-week event monitors at 3-month intervals following index ablation. Results: Baseline characteristics of Group 1 and Group 2 were similar, although in Group 1 there was a greater prevalence of patients with persistent NPAF lasting for 6-months or longer prior to initial ablation (43% vs 21%, p=0.071). The recurrence rate at 1 year as estimated by the Kaplan-Meier method was not significantly different between Group 1 and Group 2 (25.7% vs 29.7%, p=0.582). The presenting recurrent arrhythmia was most frequently atrial tachycardia (AT) in both groups (Group 1: n=19, AT 68.4% and AF 31.6% vs Group 2: n=22, AT 59.1% and AF 40.9%). A similar proportion of patients in both groups underwent repeat ablation (Group 1: 17.6% vs Group 2: 13.5%, p=0.496). Conclusions: Utilization of a CFS ablation catheter was not associated with improved clinical outcomes for stepwise catheter ablation for NPAF. The optimal strategy for NPAF ablation using a contact-force sensing catheter remains undefined

Introduction: LA ablation for persistent AF that achieves organization to atrial tachycardia (AT) or sinus rhythm (SR) predicts greater long term ablation success. However, extensive LA ablation increases the risks of recurrent AT, adverse atrial remodeling and procedural complications. Preclinical and observational studies suggest that right atrial ablation may reduce AF risk. We hypothesized that CTI ablation may reduce the extent of LA ablation required to achieve organization of persistent AF. Methods: Persistent AF patients (n=107) were randomized to two arms (CTI-first or CTI-last) in a single center, prospective, single blind study. Excluding the CTI ablation, stepwise linear LA ablation was performed in a prespecified order. The primary endpoint was the percentage of patients who organized to AT or SR. The secondary endpoint was number of steps to organization. Results: CTI ablation first versus last during AF ablation did not significantly alter the percentage of patients who organized (Table). Among those who organized, the number of steps to organization did not differ between the two arms. No significant differences were found when patients were stratified by LA size or AF duration. Conclusions: CTI ablation does not alter the extent of LA ablation needed to achieve organization of AF. The utility of right atrial ablation for persistent AF ablation remains unclear. (Table presented)

Introduction: Transcatheter aortic valve replacement (TAVR) is becoming a widely accepted alternative treatment for patients with symptomatic aortic stenosis who are at high risk for surgical aortic valve replacement. A common complication of the procedure is the development of conduction defects requiring permanent pacemaker (PPM) implantation. It has been noted that in some patients, the conduction block is not permanent. Determine the incidence and predictors of resuming intrinsic conduction in patients that receive PPM implantation after TAVR. Methods: A retrospective chart review of patients undergoing TAVR at New York University Langone Medical Center was undertaken. Extracted data included patient demographics, pre-TAVR electrocardiogram, procedural, echocardiographic, catheterization, and device interrogation data. Evaluation of device interrogations done at one month follow-up or earlier to look for resumption of intrinsic conduction. Results: There were a total number of 451 patients who were status-post TAVR in our registry at NYU. Of the 451, 45 patients received a permanent pacemaker placement for complete heart block; 9.9% 45/451. The majority of patients were implanted within 48hrs post TAVR. Device follow-up information at 1 month or earlier was available for 33 of the 45 patients who received PPM. 5 patients who were recently implanted are still pending follow-up. 3 patients expired after implantation and 4 were lost to follow-up. Of the 33 patients, 14 (42%) patients had resumption of AV nodal conduction at 1 month follow-up. 19 patients (57%) remained dependent. Conclusions: 42% of patients who received a permanent pacemaker for complete heart block after TAVR had resumption of conduction. This suggests that many patients may not require long term PPM post TAVR. Patients that remained dependent had a higher incidence of preexisting RBBB and LAFB, however a lack thereof does not preclude an increased risk. These data suggest that waiting longer than 48 hours for resumption of AV nodal conduction would avoid unnecessary implantation in patients who develop complete heart block post TAVR

Congenital absence of left atrial appendage (LAA) is an extremely rare condition and its physiological consequences are unknown. We present two cases of incidental finding of a congenitally absent LAA in a 79-year-old male who presented for routine transesophageal echocardiogram (TEE) to rule out intracardiac thrombus prior to placement of biventricular implantable cardioverter-defibrillator and a 54-year old female who presented for TEE prior to radiofrequency ablation of atrial fibrillation. Characterization of patients with such an absence is important because congenitally absent LAA may be confused with flush thrombotic occlusion of the appendage. There are very few published reports of congenital absence of LAA. To our knowledge, our report is the first to demonstrate the congenital absence of LAA by 3D transesophageal echocardiography.

OBJECTIVES/OBJECTIVE:This study aimed to evaluate the cumulative effect of treatment of obstructive sleep apnea (OSA) with continuous positive airway pressure (CPAP) on atrial fibrillation (AF) recurrence. BACKGROUND:OSA is a known predictor for onset and recurrence of AF. The effect of treatment with CPAP on AF recurrence has been evaluated in small studies with varied outcomes. METHODS:We searched MEDLINE, EMBASE, CINAHL, Google Scholar, Cochrane Database of Systematic Reviews, and Cochrane Trials Register for relevant studies. Evaluation of AF recurrence in CPAP users and nonusers in patients with OSA was the primary outcome evaluated in this study. The secondary outcome was evaluation of AF recurrence in CPAP users and nonusers after pulmonary vein isolation (PVI). RESULTS: = 0%). The beneficial effect of CPAP use was statistically significant in both groups of patients: those who underwent catheter ablation with PVI and those who did not undergo ablation and were managed medically. No other study covariates had any significant association with these outcomes of AF reduction. CONCLUSIONS:The use of CPAP is associated with significant reduction in recurrence of AF in patients with OSA. This effect remains consistent and similar across patient populations irrespective of whether they undergo PVI.