Luminal Esophageal Temperature Monitoring Research Articles

One-year freedom from arrhythmia following radiofrequency ablation using proactive oesophageal cooling

Abstract Background Proactive esophageal cooling is increasingly being utilized, and is now FDA cleared, to reduce the likelihood of ablation-related esophageal injury resulting from radiofrequency (RF) cardiac ablation of atrial fibrillation (AF). One-year follow-up from the largest randomized controlled study, the IMPACT trial, showed a trend towards improvement in long-term efficacy versus luminal esophageal temperature (LET) monitoring. With larger data sets now available for analysis, we sought to determine 1-year freedom from atrial arrhythmia associated with the use of proactive esophageal cooling. Methods Data from 2 trials comparing freedom from atrial arrhythmia after RF ablation using proactive esophageal cooling to LET monitoring were combined. Data were analyzed using a stratified Cox proportional hazards model to compare arrhythmia recurrence rates, with R statistical analysis software. Results Data from 631 patients across two studies comparing arrhythmia outcomes for proactive oesophageal cooling versus LET monitoring were analysed. Mean patient age was 66.4±9.8 years, and 37.4% were female. Arrhythmias were 56.3% paroxysmal AF and 43.7% persistent or long-standing persistent AF. Freedom from atrial arrhythmia at one year was 77.2% for patients receiving proactive oesophageal cooling and 64.4% for patients receiving LET monitoring (Figure 1), with a hazard ratio for cooling of 0.65 (95% CI 0.43 to 0.99, P = 0.044). Conclusions Proactive oesophageal cooling was associated with significantly greater freedom from atrial arrhythmia at one year when compared to LET monitoring during RF ablation.

Association between proactive esophageal cooling and increased lab throughput.

Proactive esophageal cooling has been FDA cleared to reduce the likelihood of ablation-related esophageal injury resulting from radiofrequency (RF) cardiac ablation procedures. Data suggest that procedure times for RF pulmonary vein isolation (PVI) also decrease when proactive esophageal cooling is employed instead of luminal esophageal temperature (LET) monitoring. Reduced procedure times may allow increased electrophysiology (EP) lab throughput. We aimed to quantify the change in EP lab throughput of PVI cases after the introduction of proactive esophageal cooling. EP lab throughput data were obtained from threeEPgroups. We then compared EP lab throughput over equal time frames at each site before (pre-adoption) and after (post-adoption) the adoption of proactive esophageal cooling. Over the time frame of the study, a total of 2498 PVIs were performed over a combined 74 months, with cooling adopted in September 2021, November 2021, and March 2022 at each respective site. In the pre-adoption time frame, 1026 PVIs were performed using a combination of LET monitoring with the addition of esophageal deviation when deemed necessary by the operator. In the post-adoption time frame, 1472 PVIs were performed using exclusively proactive esophageal cooling, representing a mean 43% increase in throughput (p < .0001), despite the loss of two operators during the post-adoption time frame. Adoption of proactive esophageal cooling during PVI ablation procedures is associated with a significant increase in EP lab throughput, even after a reduction in total number of operating physicians in the post-adoption group.

Esophageal injury, perforation, and fistula formation following atrial fibrillation ablation.

Esophageal perforation and fistula formation are rare but serious complications following atrial fibrillation ablation. In this review article, we outline the incidence, pathophysiology, predictors, and preventative strategies of this dreaded complication. We conducted an electronic search in 10 databases/electronic search engines to access relevant publications. All articles reporting complications following atrial fibrillation ablation, including esophageal injury and fistula formation, were included for systematic review. A total of 130 manuscripts were identified for the final review process. The overall incidence of esophageal injury following atrial fibrillation ablation was significantly higher with thermal ablation modalities (radiofrequency 5-40%, cryoballoon 3-25%, high-intensity focused ultrasound < 10%) as opposed to non-thermal ablation modalities (no cases reported to date). The incidence of esophageal perforation and fistula formation with the use of thermal ablation modalities is estimated to occur in less than 0.25% of all atrial fibrillation ablation procedures. The use of luminal esophageal temperature monitoring probe and mechanical esophageal deviation showed protective effect toward reducing the incidence of this complication. The prognosis is very poor for patients who develop atrioesophageal fistula, and the condition is rapidly fatal without surgical intervention. Esophageal perforation and fistula formation following atrial fibrillation ablation are rare complications with poor prognosis. Various strategies have been proposed to protect the esophagus and reduce the incidence of this fearful complication. Pulsed field ablation is a promising new ablation technology that may be the future answer toward reducing the incidence of esophageal complications.

Improvement in post-ablation chest pain and same-day discharge with the use of active esophageal cooling

Abstract Background Active esophageal cooling is a common method of esophageal protection during radiofrequency (RF) ablation for the treatment of atrial fibrillation (AF). Compared to the main alternative, luminal esophageal temperature (LET) monitoring, active esophageal cooling reduces esophageal injury. Recent findings in the community hospital setting indicate that procedure time and post-ablation chest pain may also be reduced, leading to greater same-day patient discharge. Objective We aimed to compare the differences in same-day discharge rates and patient-reported post-ablation chest pain between patients treated with either LET monitoring or active esophageal cooling while undergoing RF ablation in a large academic medical center. Methods We reviewed data from RF ablations performed between January 2020 and October 2022 by five attending electrophysiologists and four electrophysiology fellows. These data were extracted from Epic’s Clarity database by two clinical informaticists. Extracted data points were paired with a manual chart review of inbound phone calls, electronic messages, follow-up visits, and readmissions within 30 days of the procedure. Results A total of 175 patients underwent RF ablation between January 2020 and October 2022, with 63 (36%) patients treated with LET monitoring and 112 (64%) treated with active esophageal cooling. Chest pain was reported by 11 patients (18%) in the LET monitored group and 7 patients (6%) in the actively cooled group (P=&amp;lt;0.001). Of the patients treated with LET monitoring, 13 (20.6%) were discharged within 12 hours of admission compared to 44 (39.3%) of the patients treated with active esophageal cooling (P=0.016). Conclusions The adoption of active esophageal cooling during RF ablation was associated with less postoperative chest pain and increased same-day discharge rates.

Impact of active esophageal cooling on catheter ablation procedure times across five healthcare systems

Abstract Background Increased efficiency in procedure times may improve electrophysiology lab throughput and enhance patient care. The choice of esophageal protection method during pulmonary vein isolation (PVI) can affect procedural efficiency, with recent data suggesting that active esophageal cooling is associated with shorter procedure times when compared with luminal esophageal temperature (LET) monitoring. Objective To compare PVI procedure times before and after the adoption of active esophageal cooling in a large multicenter analysis. Methods Procedural data were obtained from 5 hospital systems before and after they adopted active esophageal cooling. Patient age, gender, and total procedure time were recorded and compared between groups before and after adoption of esophageal cooling. Results A total of 2,280 patient procedures completed by 16 different physiologists were reviewed from a total of 6 hospitals. The hospitals included academic medical centers, community hospitals, and integrated healthcare delivery systems. Prior to adopting active esophageal cooling, patients were treated with LET monitoring using either single or multi-sensor temperature probes. For the actively cooled patients the mean age was 66.7 ± 10.9 years and 33.5% were female. For the LET monitored patients the mean age was 64.2 ± 10.7 years and 34.5% were female. A total of 928 patients were treated with LET monitoring, with a mean procedure time of 173 ± 73 minutes. A total of 1352 patients were treated with active esophageal cooling, with a mean procedure time of 113 ± 51 minutes, representing a decrease of 60 minutes, or 34.7% of procedure time, compared with active esophageal cooling (P&amp;lt;.001). Conclusions Active esophageal cooling during PVI was associated with up to a 34.7% reduction in procedure duration when compared to LET monitoring in this large multicenter analysis.

Atrioesophageal Fistula Rates Before and After Adoption of Active Esophageal Cooling During Atrial Fibrillation Ablation

BackgroundActive esophageal cooling reduces the incidence of endoscopically identified severe esophageal lesions during radiofrequency (RF) catheter ablation of the left atrium for the treatment of atrial fibrillation. A formal analysis of the atrioesophageal fistula (AEF) rate with active esophageal cooling has not previously been performed. ObjectivesThe authors aimed to compare AEF rates before and after the adoption of active esophageal cooling. MethodsThis institutional review board (IRB)-approved study was a prospective analysis of retrospective data, designed before collecting and analyzing the real-world data. The number of AEFs occurring in equivalent time frames before and after adoption of cooling using a dedicated esophageal cooling device (ensoETM, Attune Medical) were quantified across 25 prespecified hospital systems. AEF rates were then compared using generalized estimating equations robust to cluster correlation. ResultsA total of 14,224 patients received active esophageal cooling during RF ablation across the 25 hospital systems, which included a total of 30 separate hospitals. In the time frames before adoption of active cooling, a total of 10,962 patients received primarily luminal esophageal temperature (LET) monitoring during their RF ablations. In the preadoption cohort, a total of 16 AEFs occurred, for an AEF rate of 0.146%, in line with other published estimates for procedures using LET monitoring. In the postadoption cohort, no AEFs were found in the prespecified sites, yielding an AEF rate of 0% (P < 0.0001). ConclusionsAdoption of active esophageal cooling during RF ablation of the left atrium for the treatment of atrial fibrillation was associated with a significant reduction in AEF rate.

Reduction in procedure duration when utilizing active esophageal cooling in patients with persistent atrial fibrillation - update from a large hospital registry

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): National Heart, Lung, And Blood Institute of the National Institutes of Health. Background During left atrial ablation, lesions may be placed on the posterior wall of the left atrium. Due to the anatomical proximity of the left atrium to the esophagus, there is significant risk for thermal esophageal injury and potentially atrio-esophageal fistula. Ablation of persistent atrial fibrillation (AF) may involve even more lesion placement, and increased risk and procedure time as a result. In order to protect the esophagus, there are two main methods of esophageal protection, luminal esophageal temperature (LET) monitoring and active esophageal cooling. Recent studies have compared LET monitoring to active cooling and found a reduction in overall esophageal injury when utilizing active cooling, in addition to a reduction in procedure time. However, these studies generally included all patients with AF regardless of which type. Purpose We aimed to investigate the association between procedure duration and esophageal protection method among persistent AF patients. Methods In this study, we obtained data from an existing clinician-maintained hospital registry. We collected procedure durations from patients with persistent AF undergoing left atrial ablation from January 2018 to May 2022. All patients that met these criteria were included. Results Data were analyzed from 161 patients. Active esophageal cooling was utilized in 90 procedures, while LET monitoring was utilized in 71 procedures. The median procedure duration in the actively cooled group was 146 minutes with an interquartile range (IQR) of 58. The median procedure duration in the LET monitored group was 173 minutes with an IQR of 60. This represents a median difference of 27 minutes or 16% of the total procedure duration (p&amp;lt;.001) Conclusions The use of active esophageal cooling is associated with a significant reduction in overall procedure time among patients with persistent atrial fibrillation.

AB-452654-3 AVOIDING THERMAL INJURY OF THE ESOPHAGUS BY USING LUMINAL ESOPHAGEAL TEMPERATURE MONITORING DURING HIGH-POWER, SHORT-DURATION RADIOFREQUENCY ABLATION: RESULTS OF A “ZERO TOLERANCE” PROTOCOL

The prevention of esophageal thermal injury (ETI) during atrial fibrillation (AF) ablation is still a challenge and the optimal luminal esophageal temperature (LET) strategy remains to be proved. Recent studies showed a lower incidence (3.5- 6%) of endoscopic ETI during high-power, short-duration (HPSD) AF ablation in which radiofrequency (RF) delivery was tolerated at LET cutoff point of 39-41°C. We investigated whether the LET monitoring with “zero tolerance” towards any rise of temperature is a safe and effective strategy in terms of endoscopic ETI and acute pulmonary vein isolation (PVI) in HPSD ablation. Observational study of consecutive patients with symptomatic AF undergoing HPSD RF ablation. The previously estimated sample size was 87, considering an estimated prevalence of 6%, margin of error of 5%, and 95% of significance level. HPSD RF ablation was defined as maximum temperature at 43°C, power delivery at 50 or 40 W for 5 and 10 seconds, respectively (the lowest power was at the left atrium posterior wall [LAPW]), 20 ml/min., and contact force of 5-30 grams. The applications were monitored by the impedance curve and real-time LET using a 9F insulated single thermocouple temperature probe. The “zero-tolerance” protocol was defined as stopping the point-by-point RF delivery at any LET rise in the LAPW in which the tip of the temperature probe was always positioned, via fluoroscopy vision, at the closest ablation site. The RF application was resumed only after the LET fell back to the baseline. All patients were scheduled to undergo esophageal endoscopy 1-3 days after procedure. We included 87 consecutive patients (59±13 years, 62 [71%] males) with paroxysmal (58[66.6%] and persistence AF (29[33.3%]). PVI was achieved in all patients with 16±7 min. of fluoroscopy time and 168±38 min. of procedure time. The LET rose in 86 (98.8%) patients, with a mean peak temperature of 37.3±1.2°C. There were no major complications. All patients underwent esophageal endoscopy and no ETI was found. They were discharged on the day after the procedure and no complications, including esophagus perforation or atrio-esophageal fistula, were clinically detected in at least 3 months of follow-up. The LET monitoring with “zero tolerance” towards any rise of temperature in HPSD RF ablation of AF prevented the occurrence of endoscopic esophageal thermal lesion without compromising the acute PVI.

Improved 1-year outcomes after active cooling during left atrial radiofrequency ablation

BackgroundActive esophageal cooling during pulmonary vein isolation (PVI) with radiofrequency (RF) ablation for the treatment of atrial fibrillation (AF) is increasingly being utilized to reduce esophageal injury and atrioesophageal fistula formation. Randomized controlled data also show trends towards increased freedom from AF when using active cooling. This study aimed to compare 1-year arrhythmia recurrence rates between patients treated with luminal esophageal temperature (LET) monitoring versus active esophageal cooling during left atrial ablation.MethodData from two healthcare systems (including 3 hospitals and 4 electrophysiologists) were reviewed for patient rhythm status at 1-year follow-up after receiving PVI for the treatment of AF. Results were compared between patients receiving active esophageal cooling (ensoETM, Attune Medical, Chicago, IL) and those treated with traditional LET monitoring using Kaplan–Meier estimates.ResultsA total of 513 patients were reviewed; 253 received LET monitoring using either single or multi-sensor temperature probes; and 260 received active cooling. The mean age was 66.8 (SD ± 10) years, and 36.8% were female. Arrhythmias were 60.1% paroxysmal AF, 34.3% persistent AF, and 5.6% long-standing persistent AF, with no significant difference between groups. At 1-year follow-up, KM estimates for freedom from AF were 58.2% for LET-monitored patients and 72.2% for actively cooled patients, for an absolute increase in freedom from AF of 14% with active esophageal cooling (p = .03). Adjustment for the confounders of patient age, gender, type of AF, and operator with an inverse probability of treatment weighted Cox proportional hazards model yielded a hazard ratio of 0.6 for the effect of cooling on AF recurrence (p = 0.045).ConclusionsIn this first study to date of the association between esophageal protection strategy and long-term efficacy of left atrial RF ablation, a clinically and statistically significant improvement in freedom from atrial arrhythmia at 1 year was found in patients treated with active esophageal cooling when compared to patients who received LET monitoring. More rigorous prospective studies or randomized studies are required to validate the findings of the current study.

Improved hospital discharge and cost savings with esophageal cooling during left atrial ablation

BackgroundLeft atrial ablation to obtain pulmonary vein isolation (PVI) for the treatment of atrial fibrillation (AF) is a technologically intensive procedure utilizing innovative and continually improving technology. Changes in the technology utilized for PVI can in turn lead to changes in procedure costs. Because of the proximity of the esophagus to the posterior wall of the left atrium, various technologies have been utilized to protect against thermal injury during ablation. The impact on hospital costs during PVI ablation from utilization of different technologies for esophageal protection during ablation has not previously been evaluated.ObjectiveTo compare the costs of active esophageal cooling to luminal esophageal temperature (LET) monitoring during left atrial ablation.MethodsWe performed a time-driven activity-based costing (TDABC) analysis to determine costs for PVI procedures. Published data and literature review were utilized to determine differences in procedure time and same-day discharge rates using different esophageal protection technologies and to determine the cost impacts of same-day discharge versus overnight hospitalization after PVI procedures. The total costs were then compared between cases using active esophageal cooling to those using LET monitoring.ResultsThe effect of implementing active esophageal cooling was associated with up to a 24.7% reduction in mean total procedure time, and an 18% increase in same-day discharge rate. TDABC analysis identified a $681 reduction in procedure costs associated with the use of active esophageal cooling after including the cost of the esophageal cooling device. Factoring in the 18% increase in same-day discharge resulted in an increased cost savings of $2,135 per procedure.ConclusionsThe use of active esophageal cooling is associated with significant cost-savings when compared to traditional LET monitoring, even after accounting for the additional cost of the cooling device. These savings originate from a per-patient procedural time savings and a per-population improvement in same-day discharge rate.

Abstract 14986: Reduced Arrhythmia Recurrence at One-Year When Using Active Esophageal Cooling

Introduction: The use of active esophageal cooling instead of traditional luminal esophageal temperature (LET) monitoring during left atrial ablation for the treatment of atrial fibrillation (AF) allows contiguous lesion placement with fewer partially-formed lesions and less catheter repositioning than required with LET monitoring. As a consequence, fewer electrical reconnections, and a lower rate of atrial arrhythmia recurrence, may result. We aimed to determine the association between esophageal protective strategy and recurrence of arrhythmia at one-year. Methods: We performed an IRB-approved review of an existing hospital registry to measure the association between recurrence of arrhythmia at one year follow-up and the use of active esophageal cooling as opposed to LET monitoring. Data were collected from ablations performed between 2017 and 2020. For each patient we recorded the type of esophageal temperature management, rhythm status at one-year follow-up, ejection fraction, and CHA 2 DS 2 -VASc score. Results: Data from a total of 247 ablations were collected. There were 95 ablations that occurred in the actively cooled group and 152 in the LET monitored group. Among those in the actively cooled group, the average CHA 2 DS 2 -VASc score was 1.8, and the average ejection fraction was 61%. In the LET monitored group, the average CHA 2 DS 2 -VASc score was 1.2 and the average ejection fraction was 61%. In the LET monitored group, there were 36 patients who had atrial arrhythmias at one-year follow-up, representing a 24% recurrence rate. In the actively cooled group, 11 patients had recurrence of arrhythmia at one-year, representing a 12% recurrence rate (P=0.02). Conclusions: Patients treated with active esophageal cooling during left atrial ablation had a significantly lower atrial arrhythmia recurrence rate at one-year follow-up when compared to patients provided with traditional LET monitoring during left atrial ablation procedures.

An Esophageal Cooling Device During Radiofrequency Ablation for Atrial Fibrillation-A Comparison Between Reactive and Proactive Esophageal Cooling.

Esophageal thermal injury is one of the most feared risks of ablation of the posterior left atrium despite the various devices used to monitor esophageal temperature or deviate the esophagus. Reactive cooling, in which cold water is manually instilled into the esophagus via an orogastric tube in response to rises in luminal esophageal temperature (LET), has been used by operators, but the availability of a dedicated esophageal cooling device offers the ability to provide proactive esophageal cooling without having to react to individual temperature rises in the esophagus. The objective of this study was to evaluate the feasibility of using a commercially available esophageal cooling device to provide esophageal protection during left atrial catheter ablation, then to compare this approach to standard LET monitoring with reactive cooling via manual cold-water instillation. In this study, we randomized 6 patients undergoing catheter ablation for atrial fibrillation. Three patients received the standard of care for our site (use of a single-sensor temperature probe, with adjunct ice-water instillation for any temperature increases of >1°C). Three patients underwent standard ablation after placement of the esophageal cooling device at a circulating water temperature of 4°C, without the use of any esophageal temperature monitoring. All patients underwent transesophageal echocardiography and esophagogastroduodenoscopy on the day prior to the ablation, followed by a second esophagogastroduodenoscopy the day after. The 6 patients in this study were enrolled between March and August 2018. In the 3 control patients, 1 had no evidence of esophageal mucosal damage, 1 had diffuse sloughing of the esophageal mucosa and multiple ulcerations, and 1 had a superficial ulcer with a large clot. Both patients with lesions were classified as 2a cases using the Zargar grading scheme for caustic injury. In the 3 patients treated with the cooling device, 1 had no evidence of esophageal mucosal damage, 1 had esophageal erythema (Zargar grade 1), and 1 had a solitary Zargar grade 2a lesion. At 3 months of follow-up, 1 patient in each group had recurrence of atrial fibrillation. Although a number of subsequent studies have confirmed the reduction of esophageal injury with the use of proactive esophageal cooling, this study is the only one to date to compare reactive cooling (via manual cold-water instillation) and proactive cooling (via a dedicated esophageal cooling device). Moreover, this is the first study to support the feasibility of using a dedicated cooling device for this purpose and provides the basis for further investigation.

Significant procedure length reduction when utilizing active esophageal cooling – a six-year single center study

Abstract Background A number of factors can influence procedure duration of left atrial ablation for the treatment of atrial fibrillation (AF). In addition to ablation techniques, the use of auxiliary tools such as intraoperative fluoroscopy and luminal esophageal temperature (LET) monitoring may impact procedure duration. However, unlike recent trends toward zero-fluoroscopy procedures, there has not been a widespread transition to alternative means of esophageal protection. Multi sensor LET monitoring leads to frequent pauses during ablations when dangerous esophageal temperatures have been reached. Although an increased risk of esophageal injury when utilizing LET monitoring as compared to active esophageal cooling has been suggested in recent studies, the degree to which LET monitoring impacts procedure duration has not been well documented. Consequently, we aimed to compare procedure duration in a large single center before and after active esophageal cooling was implemented in place of LET monitoring. Objective Review procedural timing data at a single large hospital before and after the implementation of active esophageal cooling in place of LET monitoring, and compare differences in procedure duration. Methods Using an existing hospital registry of ablation procedures, we obtained procedure durations for left atrial ablations for AF before and after the implementation of active esophageal cooling into the hospital protocol. Data was collected with IRB approval from a single hospital from January 2015 through November 2021. Prior to September 2018, multi-sensor LET monitoring was utilized in all patients, whereas all patients afterwards were treated with active esophageal cooling. Results Data was analyzed from a total of 412 patients. LET monitoring was utilized with 176 patients, while active esophageal cooling was utilized with 236 patients. In the LET monitored group the median procedure length was 191 minutes with an interquartile range (IQR) of 91 minutes. In the actively cooled group, the median procedure length was 147 minutes with an IQR of 61 minutes. This represents a median difference of 44 minutes, or 23% of total procedure time (p&amp;lt;0.001). Conclusion When compared to LET monitoring, the use of active esophageal cooling is associated with a significant time savings in PVI procedures. Funding Acknowledgement Type of funding sources: Private company. Main funding source(s): Attune Medical

Reduced Procedure Time and Variability with Active Esophageal Cooling During Radiofrequency Ablation for Atrial Fibrillation.

Various methods are utilized during radiofrequency (RF) pulmonary vein isolation (PVI) for the treatment of atrial fibrillation (AF) to protect the esophagus from inadvertent thermal injury. Active esophageal cooling is increasingly being used over traditional luminal esophageal temperature (LET) monitoring, and each approach may influence procedure times and the variability around those times. The objective of this study is to measure the effects on procedure time and variability in procedure time of two different esophageal protection strategies utilizing advanced informatics techniques to facilitate data extraction. Trained clinical informaticists first performed a contextual inquiry in the catheterization laboratory to determine laboratory workflows and observe the documentation of procedural data within the electronic health record (EHR). These EHR data structures were then identified in the electronic health record reporting database, facilitating data extraction from the EHR. A manual chart review using a REDCap database created for the study was then performed to identify additional data elements, including the type of esophageal protection used. Procedure duration was then compared using summary statistics and standard measures of dispersion.A total of 164 patients underwent radiofrequency PVI over the study timeframe; 63 patients (38%) were treated with LET monitoring, and 101 patients (62%) were treated with active esophageal cooling. The mean procedure time was 176 min (SD of 52 min) in the LET monitoring group compared to 156 min (SD of 40 min) in the esophageal cooling group (P = 0.012). Thus, active esophageal cooling during PVI is associated with reduced procedure time and reduced variation in procedure time when compared to traditional LET monitoring.

Esophageal image segmentation for guidance of posterior wall lesions during atrial fibrillation ablation.

Despite luminal esophageal temperature (LET) monitoring, esophageal injury remains a risk which impacts decision making during atrial fibrillation (AF) ablation. We sought to compare procedural characteristics including radiofrequency (RF) power, duration, and LET, among ablation procedures with and without image segmentation for esophageal visualization (EV). The retrospective cohort included 73 patients (mean age 65.2 ± 8.6years, 36% female, 55% paroxysmal AF) who underwent pre-procedural cardiac magnetic resonance or computed tomography and LET monitoring. Of all patients, 35 were historical patients that underwent standard AF ablation without EV, and 38 were contemporary patients, 28 of whom underwent AF ablation with EV and 10 that underwent AF ablation without EV. Total RF time was similar between the groups. The distribution of ablation power delivery was skewed toward higher power in the contemporary patients. However, among patients in the contemporary group, the proportion of > 35 Watts lesions was lower with EV (P < 0.001). There was no difference between the max or mean LET. The standard deviation of LET change within patient during posterior wall ablation was lower in those with esophageal visualization compared to historical controls, but no change was seen compared to a smaller group of contemporary controls. No long-term clinical esophageal injury was observed. In a retrospective analysis, EV was successfully performed in 28 patients. EV impacted RF power delivery decisions but was unassociated with RF time, changes in LET, or long-term safety.

Arrhythmia recurrence reduction with an active esophageal cooling device during radiofrequency ablation

Abstract Funding Acknowledgements Type of funding sources: None. Background As the burden of atrial fibrillation continues to rise with an aging population, there have been contrasting positions on the efficacy of left atrial ablation. While ablation techniques have continued to improve over the past decades, arrhythmia recurrence rates must be further reduced given the burden of ablation on patients. Since continuity of lesion sets has been associated with greater lesion durability, it has been theorized that the use of active esophageal cooling may facilitate greater freedom from arrhythmia. Purpose In order to investigate the association between use of active esophageal cooling and arrhythmia recurrence, we performed a multicenter retrospective study of arrhythmia recurrence rates in patients that received active cooling and compared them to those that received luminal esophageal temperature (LET) monitoring. Methods In this study, follow up data were collected from patients that underwent pulmonary vein isolation (PVI) at three separate large medical centers. Data were contained in a prospective hospital registry, a prospective physician registry, or the electronic health record, depending on the center. For each patient included, we recorded whether their ablation utilized LET monitoring or active esophageal cooling, along with their rhythm status at 1-year follow up. Rhythm status at follow-up was determined by either electrocardiogram, Holter monitor, or wearable heart rate monitor. Kaplan-Meier (KM) curves were created for freedom-from-arrhythmia at one year comparing those in the LET monitoring group to those in the active cooling group. Results Follow up data were collected from 1035 patients. There were 560 patients that received LET monitoring during their original ablation, and 475 patients that underwent active esophageal cooling. KM estimates for freedom-from-arrhythmia at one year were 42% in the LET monitored group and 65% in the actively cooled group (P&amp;lt;.001). Conclusion In this large multicenter study, there is a significant increase in freedom-from-arrhythmia at one year follow-up among patients that received active esophageal cooling as compared to those that underwent LET monitoring.

Effect of a proactive esophageal cooling device on procedure length - a multicenter comparison of persistent and paroxysmal atrial fibrillation

Abstract Funding Acknowledgements Type of funding sources: None. Background During left atrial ablation for the treatment of atrial fibrillation (AF), effective esophageal protection is essential for reducing or preventing thermal injury. Traditional methods include luminal esophageal temperature (LET) monitoring that lead to frequent pauses in the procedure when temperature alarms alert operators to dangerous temperature levels. While there have been recent studies that demonstrate an association between active esophageal cooling and a reduction in procedure duration regardless of AF type, these retrospective studies have been conducted at single or joint centers which may lead to confounding from other time-saving variables that have changed over time. Purpose Consequently, we sought to perform a large-scale multicenter comparison to better elucidate the association between procedure length and the use of active cooling in patients with persistent and paroxysmal atrial fibrillation. Methods In this study, we collected data from three large hospital centers, one hospital-maintained registry, one physician-maintained registry, and one through EHR data review and aggregated in groups separated by AF type as well as whether the patients received active cooling or LET monitoring. We then compared median procedure durations in each group. Results There were a total of 753 patients included in this study. Of the 360 patients with paroxysmal AF, 179 received active esophageal cooling while 181 underwent LET monitoring. In the persistent AF group with 393 patients, 157 received active esophageal cooling and 236 underwent LET monitoring. Among patients with paroxysmal AF, the median mean procedure duration was 137 minutes in the LET monitored group, and 90 minutes in the actively cooled group with an overall reduction of 47 minutes (P&amp;lt;.001). In patients with persistent AF, the median procedure duration was 148 minutes in the LET monitored group and 94 minutes in the actively cooled group with an overall reduction of 54 minutes (P&amp;lt;.001). The relative reduction as a percent of total procedure time was 34%, and 36%, for paroxysmal and persistent AF cases, respectively. Conclusion In this large multicenter review, there is a significant reduction in procedure length when using active esophageal cooling, regardless of AF type.

Procedural time reduction associated with active esophageal cooling during pulmonary vein isolation

BackgroundActive esophageal cooling is increasingly utilized as an alternative to luminal esophageal temperature (LET) monitoring for protection against thermal injury during pulmonary vein isolation (PVI) when treating atrial fibrillation (AF). Published data demonstrate the efficacy of active cooling in reducing thermal injury, but impacts on procedural efficiency are not as well characterized. LET monitoring compels pauses in ablation due to heat stacking and temperature overheating alarms that in turn delay progress of the PVI procedure, whereas active esophageal cooling allows avoidance of this phenomenon. Our objective was to measure the change in PVI procedure duration after implementation of active esophageal cooling as a protective measure against esophageal injury.MethodsWe performed a retrospective review under IRB approval of patients with AF undergoing PVI between January 2018 and February 2020. For each patient, we recorded age, gender, and total procedure time. We then compared procedure times before and after the implementation of active esophageal cooling as a replacement for LET monitoring.ResultsA total of 373 patients received PVI over the study period. LET monitoring using a multi-sensor probe was performed in 198 patients, and active esophageal cooling using a dedicated device was performed in 175 patients. Patient characteristics did not significantly differ between groups (mean age of 67 years, and gender 37.4% female). Mean procedure time was 146 ± 51 min in the LET-monitored patients, and 110 ± 39 min in the actively cooled patients, representing a reduction of 36 min, or 24.7% of total procedure time (p < .001). Median procedure time was 141 [IQR 104 to 174] min in the LET-monitored patients and 100 [IQR 84 to 122] min in the actively cooled patients, for a reduction of 41 min, or 29.1% of total procedure time (p < .001).ConclusionsImplementation of active esophageal cooling for protection against esophageal injury during PVI was associated with a significantly large reduction in procedure duration.

Abstract 10387: Utility of Esophageal Image Segmentation for Guidance of Posterior Wall Lesions During Atrial Fibrillation Ablation

Introduction: Despite luminal esophageal temperature (LET) monitoring, esophageal injury remains a risk which impacts decision making during atrial fibrillation (AF) ablation. We sought to compare procedural characteristics including radiofrequency (RF) power, duration, and LET, among ablation procedures with and without visualization of esophageal segmentations relative to the left atrial dome. Hypothesis: We sought to test the hypothesis that esophageal image registration and visualization during AF ablation would improve operator efficiency and reduce esophageal temperature changes during the procedure. Methods: The retrospective cohort included 63 patients (mean age 65.5 ± 8.8 years, 33% female, 54% paroxysmal AF) that underwent pre-procedural cardiac magnetic resonance (CMR) and LET monitoring. Of all patients, 35 underwent standard AF ablation without esophageal image segmentation, and 28 underwent AF ablation with registration of esophageal image segmentation. Results: Total RF time was shorter with esophageal visualization (28.6 ± 11.8 min versus 39.1 ± 22.5 min, P&lt;0.05). The distribution of ablation power delivery was skewed toward higher power with esophageal visualization (P&lt;0.001), while the mean LET was identical among patient groups and the standard deviation of LET was lower in those with esophageal visualization (35.9 ± 0.5 °C versus 35.9 ± 0.7 °C, P=NS). The within patient standard deviation for LET change during posterior wall ablation was 0.3 ± 0.1 °C and 0.4 ± 0.2 °C for patients with and without esophageal visualization respectively (P=0.017). Conclusions: Esophageal visualization was associated with improved efficiency of AF ablation using higher power and resulting in shorter RF time, while reducing the variation in esophageal temperature.

Abstract 12177: Analysis of the Primery Factor Which Predicts the Incidence of Esophageal Injury After Catheter Ablation of Atrial Fibrillation

Background: Esophageal injury (EI) is a serious complication after radiofrequency catheter ablation (CA) of atrial fibrillation (AF).Although life-threatening complications are rare, CA of posterior wall of left atrium (LA) may result in EI ranging from mild erythema to ulceration. However, predictable factor of EI is unclear. A recent study appreciably suggested that postprocedural upper gastrointestinal tract endoscopy could identify EI, and higher intraesophageal temperature measured by a luminal esophageal temperature monitoring (ETM) was associated with the occurrence of EI. Until now, there is no widely accepted approach to minimize EI caused by CA for AF. Objective: We sought to identify risk factors of EI caused by CA for AF, and explore the potential management of EI in this study. Methods: Among 568 patients who underwent CA of AF, endoscopy was performed the next day after CA to examine for EI. The incidence of EI was compared between 260 patients who done ETM (ETM group) and 308 patients who didn’t done ETM (Non-ETM group) during CA. The Shortest Distance between esophagus and posterior left atrium measured on contrast Computed Tomography (SD-CT) was also compared between both groups. Results: No differences were observed between both groups in total number and amount of applications. However, EI occurred more frequently in Non-ETM group (9/260 patients; 3.4 % vs 27/308 patients; 8.8 %, p=0.042). There was no significant difference in SD-CT between ETM and Non-ETM group. However, SD-CT in patients with EI was significantly shorter than SD-CT in patients without EI, both in ETM (2.3±0.6 vs 4.1±0.8mm, p&lt;0.001) and in Non-ETM group (2.3±0.3 vs 4.1±1.3 mm, p&lt;0.001), respectively. The rising speed of temperature was faster in patients with EI than those without EI (7.6±5.6 vs 10.7±6.2 sec, p=0.025). Maximum arrival temperature of esophagus was higher in patients with EI than those without EI (42.4±5.7 vs 41.2±1.5, p=0.038).Receiver operating characteristic curves were constructed to assess the ability of SD-CT and esophageal temperature to predict EI. Conclusions: The use of ETM is safe and necessary in order to prevent the occurrence of EI. The incidence of EI was correlated with SD-CT. ETM reduced EI, especially in patients with short SD-CT.