Esophageal Temperature Probe Research Articles

Impact of age on the management and prognosis of oesophageal fistula after atrial fibrillation ablation - a subanalysis of the worldwide POTTER-AF study

Abstract Background Oesophageal fistula (OF) is a rare but devastating complication following atrial fibrillation (AF) ablation. The data regarding the impact of age on the management and prognosis of OF are scarce. Methods The POTTER-AF study is a worldwide, multi-centre registry conducted under the auspices of the Working Group of Cardiac Electrophysiology of the German Cardiac Society (AGEP, DGK) which evaluated the incidence, management and outcome of post-procedural OF following catheter ablation of AF. A total of 553 729 patients underwent ablation procedures for AF or atrial tachycardia (AT) in 214 electrophysiological centres from 35 countries between 1996 and 2022. Of them, 138 (0.025%) patients experienced postprocedural OF and data regarding the management and prognosis were available in 113 patients. The median age was 63 years. Results A total of 54 (47.8%) patients experiencing OF were younger than 63 years old (Group 1), while 59 (52.2%) patients were at least 63 years old (Group 2). No difference was noted between the groups regarding the incidence of atrioesophageal fistula, oesophageal perforation, and oesophageal-pericardial fistula. Almost half of the patients in each group were females (44.4% vs. 48.3%; p=0.813). As expected, a CHA2DS2-VASc score higher than 3 was more frequent in the older population (61% vs. 17.3%; p<0.001). Regarding the comorbidities, the patients in Group 2 were more likely to suffer from coronary artery disease (25% vs. 9.8%; p=0.046) and hypertension (72.9% vs. 42.6%; p=0.001). The two populations were similar in terms of sedation type, energy source and ablation techniques used, as well as in terms of oesophageal temperature probe utilization. Interestingly, the older population had a shorter median time to symptoms onset (15 (6, 21) vs. 21 (10, 25.3) days; p=0.031). Fever, chest pain and neurological signs as first manifestations of OF showed similar incidences between the groups. When analysing the diagnostic method, the patients from Group 2 were less likely to receive a cranial computed tomography (cCT) or cranial magnetic resonance imaging (cMRI) (25.9% vs. 45.3%; p=0.046). The older population was more likely to receive a direct endoscopic treatment, without surgery (27.6% vs. 11.3%; p=0.035), while there was no difference regarding the rate of surgical treatment. The conservative treatment was used in similar proportions (37.7% in Group 1 vs. 29.3% in Group 2; p=0.421). A clear trend towards a higher mortality was noted in the older population (72.9% vs. 56.6%; p=0.078). The incidence of major and minor sequalae was similar for both groups. Conclusion The median age of the OF population was 63 years. The older population had a shorter time to symptoms onset, was less likely to receive cCT/cMRI as diagnostic method and more likely to be treated by direct endoscopic treatment. The patients older than 63 years showed a trend towards a higher mortality.Time to symptoms onsetOutcome

Impact of gender on the management and prognosis of oesophageal fistula after atrial fibrillation ablation - a subanalysis of the worldwide POTTER-AF study

Abstract Background Oesophageal fistula (OF) is a rare but devastating complication following atrial fibrillation (AF) ablation. The data regarding the impact of gender on the management and prognosis of OF are scarce. Methods The POTTER-AF study is a worldwide, multi-centre registry conducted under the auspices of the Working Group of Cardiac Electrophysiology of the German Cardiac Society (AGEP, DGK) which evaluated the incidence, management, and outcome of post-procedural OF following catheter ablation of AF. A total of 553 729 patients underwent ablation procedures for AF or atrial tachycardia (AT) in 214 electrophysiological centres from 35 countries between 1996 and 2022. Of them, 138 (0.025%) patients experienced postprocedural OF and data regarding the gender, management and prognosis were available in 117 patients. Herein we conducted a gender- based analysis of the patients exhibiting OF. Purpose To evaluate the impact of gender on the management and prognosis of OF. Results Females represented 47% of the study population, which is a notable finding considering that the female population represents only a minority of the patients receiving AF/AT ablation. They were less likely to have atrioesophageal fistula (90.9% vs. 100%; p=0.021). Oesophageal-pericardial fistula occurred solely in females (7.3% vs. 0%; p=0.046). Congestive heart failure was significantly less frequent in the female population (7.4% vs. 26.7%; p=0.012). No other difference was seen between genders regarding the baseline characteristics and comorbidities (Table1). The energy source, ablation technique and utilization of oesophageal temperature probes were similar for males and females. Significantly less women received proton pump inhibitors (PPI) postprocedural (64.8% vs. 84.7%; p=0.017). The median duration until onset of symptoms was 20 days for women and 16.5 days for men (p=0.14), while the median duration until OF diagnosis was 22.5 days and 19.5 days respectively (p=0.217). Significantly more women underwent echocardiography (36.4% vs. 15%; p=0.01) as diagnostic method. More women exhibited stroke (32.7% vs. 14.8%; p=0.040), while there was no significant difference regarding the incidence of septic shock, coma, cardiac arrest, cardiac tamponade, and gastro-intestinal bleeding. Significantly more women than men presented no complications other than OF (9.6% vs. 0%; p=0.026). The females were more likely to undergo endoscopic treatment (35.8% vs. 17.7%; p=0.034), but less likely to undergo direct surgical treatment, without stenting (28.3% vs. 51.6%; p=0.014) (Figure1). The mortality was 63.6% for women and 67.2% for men (p=0.70), with no difference in terms of major and minor sequelae. Conclusion Approximatively half of the patients exhibiting postprocedural OF are females. Women showed a higher rate of endoscopic treatment and a lower rate of direct surgical treatment. The survival, as well as the incidence of minor and major sequelae were similar between genders.

Can Oesophageal Temperature Probes Prevent Oesophageal Injury During Catheter Ablation of Atrial Fibrillation?

Can Oesophageal Temperature Probes Prevent Oesophageal Injury During Catheter Ablation of Atrial Fibrillation?

Exercise-induced arterial hypoxemia in female masters athletes

The purpose of the study was to characterize exercise induced arterial hypoxemia (EIAH) in female masters athletes (FMA). We hypothesized that FMA would experience EIAH during treadmill running. Eight FMA (48–57 years) completed pulmonary function testing and an incremental exercise test until exhaustion (V̇O2max⁡ = 45.7 ± 6.5, range:35–54 ml/kg/min). On a separate day, the participants were instrumented with a radial arterial catheter and an esophageal temperature probe. Participants performed three to four constant load exercise tests at 60–70 %, 75 %, 90 %, 95 %, and 100 % of maximal oxygen uptake while sampling arterial blood and recording esophageal temperature. We found that FMA decrease their partial pressure of oxygen (86.0 ± 7.6, range:73–108 mmHg), arterial saturation (96.2 ± 1.2, range:93–98 %), and widen their alveolar to arterial oxygen difference (23.2 ± 8.8, range:5–42 mmHg) during all exercise intensities however, with variability in terms of severity and pattern. Our findings suggest that FMA experience EIAH however aerobic fitness appears unrelated to occurrence or severity (r = 0.13, p = 0.756).

Critically buried avalanche victims can develop severe hypothermia in less than 60 min

BackgroundA major challenge in the management of avalanche victims in cardiac arrest is differentiating hypothermic from non-hypothermic cardiac arrest, as management and prognosis differ. Duration of burial with a cutoff of 60 min is currently recommended by the resuscitation guidelines as a parameter to aid in this differentiation However, the fastest cooling rate under the snow reported so far is 9.4 °C per hour, suggesting that it would take 45 min to cool below 30 °C, which is the temperature threshold below which a hypothermic cardiac arrest can occur.Case presentationWe describe a case with a cooling rate of 14 °C per hour, assessed on site with an oesophageal temperature probe. This is by far the most rapid cooling rate after critical avalanche burial reported in the literature and further challenges the recommended 60 min threshold for triage decisions. The patient was transported under continuous mechanical CPR to an ECLS facility and rewarmed with VA-ECMO, although his HOPE score was 3% only. After three days he developed brain death and became an organ donor.ConclusionsWith this case we would like to underline three important aspects: first, whenever possible, core body temperature should be used instead of burial duration to make triage decisions. Second, the HOPE score, which is not well validated for avalanche victims, had a good discriminatory ability in our case. Third, although extracorporeal rewarming was futile for the patient, he donated his organs. Thus, even if the probability of survival of a hypothermic avalanche patient is low based on the HOPE score, ECLS should not be withheld by default and the possibility of organ donation should be considered.

Pulsed field ablation based pulmonary vein isolation utilizing a simplified approach

Abstract Funding Acknowledgements Type of funding sources: None. Background Pulsed field ablation (PFA) is a novel non-thermal energy source with promising safety and efficacy advantages compared to standard ablation technologies. Purpose We aimed to develop a safe, effective and fast pulmonary vein isolation (PVI) utilizing a single shot PFA catheter via a single femoral vein puncture and a venous closure system approach. Methods Forty-eight consecutive AF patients underwent first-time PVI via PFA under deep sedation. A single ultrasound guided femoral vein puncture and a single transseptal puncture was utilized for left atrial access. After pulmonary vein (PV) angiography eight pulse trains (2kV/2.5 sec, bipolar, biphasic, each 4x basket/flower configuration) were delivered to each PV. Extra pulse trains in the flower configuration (8x) were added to the posterior wall for very wide antral circumferential ablation (vWACA). Continuous intraluminal esophageal temperature (TESO) was monitored with a s-shaped esophageal temperature probe. A venous closure system was utilized on the single access site. A Donati suture was performed. The pressure bandage was removed after 1h. Results Patients (mean age: 64 +/-11 years) presented with AF (paroxysmal 58% or persistent AF (42%). A total of 192 PV were identified and isolated via PFA (100%). A mean of 40 pulse trains for PVI and vWACA have been used. The mean procedural time was 27 +/- 7 minutes, the mean catheter dwell time was 14 +/- 6 minutes and the median fluoroscopy time was 6 +/- 2 minutes. No relevant esophagus temperature rise occurred. One patient (2%) experienced a transient phrenic nerve palsy which recovered until the end of the procedure. Two patients (4%) experienced a superficial bleeding which was treated by a figure of eight suture. No severed hematoma, transfusion or intervention was necessary. No pericardial effusion or tamponade occurred. Conclusion The combination of a single vein single transseptal puncture approach resulted in a 100% rate of acute PVI and an extraordinary fast procedure and dwell time. The rate of periprocedural complications was low.

PO-01-104 3D MODELING OF PRE-PROCEDURE CT SCAN TO PREDICT SEVERE ESOPHAGEAL HEATING DURING HIGH POWER SHORT DURATION ATRIAL FIBRILLATION ABLATION

The degree of esophageal heating during left atrial posterior wall (LAPW) ablation is a powerful predictor of esophageal injury. Esophageal temperature monitoring has not been shown, however, to reduce esophageal injury risk related to atrial fibrillation (AF) ablation. Esophageal proximity modeling based on pre-procedure CT scan using ADAS 3D software (ADAS3D Medical, Barcelona, Spain) is a novel method of identifying left atrial locations at high risk for severe esophageal heating. Given the mobile nature of the esophagus relative to the LAPW, the predictive value of esophageal proximity mapping is unclear. To determine the predictive value of esophageal proximity mapping to identify LAPW ablation sites at risk for severe esophageal heating. Pre-procedure CT scans were analyzed using ADAS 3D software in 10 patients undergoing AF ablation to create a 3D esophageal proximity model and left atrial tissue thickness map that were merged with a catheter based left atrial electroanatomic map (Ensite X, Abbott, Inc.). Esophageal proximity was defined as: Zone 1 – overlying esophagus, Zone 2 – within 5 mm of esophagus, or Zone 3 – > 5 mm from esophagus. LAPW ablation lesions were created with a contact-force sensing radiofrequency ablation catheter (Tacticath, Abbott, Inc.) at 45W, 10-20g of force, and 6 seconds duration. A 12 sensor esophageal temperature probe (Circa, Circa Scientific, Inc.) recorded the temperature increase related to each LAPW lesion. Ablation lesions in Zone 3 resulted in significantly lower esophageal temperature rise (degrees Celsius) as compared to either Zone 1 (mean 0.11 ± 0.27 vs 1.61 ± 1.39, p value <0.0001) or Zone 2 (mean 0.11 ± 0.27 vs 0.84 ± 1.1, p value <0.0001) (Fig A). Lesions in Zone 2 resulted in lower temperature rise as compared to Zone 1 (mean 0.84 ±1.1 vs. 1.61 ± 1.39, p value <0.0001) (Fig A). Within Zones 1 and 2, lesions with LAPW thickness > 2 mm resulted in significantly less esophageal temperature rise as compared to those on tissue with thickness of ≤ 2 mm (Fig B). Ablation lesions delivered >5mm from esophageal location at time of pre-procedure CT scan are very unlikely to result in significant esophageal heating. Ablation sites overlying esophagus with LAPW thickness ≤ 2mm were at greatest risk of significant esophageal heating. Analysis of pre-procedure CT scans to determine esophageal proximity and LAPW thickness may be useful in developing strategies to avoid esophageal injury during LAPW RF ablation.

Esophageal luminal temperature monitoring using a multi-sensor probe lowers the risk of esophageal injury in cryo and radiofrequency catheter ablation for atrial fibrillation.

Esophageal luminal temperature monitoring is a commonly used strategy to reduce esophageal thermal injury in catheter ablation for atrial fibrillation (AFib). We sought to compare the incidence of endoscopically detected esophageal lesions (EDEL) between two commonly used esophageal luminal temperature probes. Consecutive patients undergoing ablation with esophageal luminal temperature monitoring and upper endoscopy within 24h after ablation were included. Four hundred forty-five patients (64 ± 10years, 44% female) were included. Esophageal temperature monitoring was done with a single-sensor probe in 213 (48%) and multi-sensor probe in 232 (52%). Cryoballoon (CB) ablation was performed in 118 (27%) and radiofrequency (RF) ablation in 327 (73%) of patients. EDEL was present in 94 (22.9%) of which 85 were mild, 8 were moderate, and 1 was severe, and none progressed to atrial-esophageal fistula. The use of the multi-sensor probe during CB ablation was associated with a reduction in EDEL compared to single sensor (6.8% vs 24.3%; P = 0.016). Similarly, in the RF ablation group, EDEL was present in 19.5% of the multi-sensor group vs 32.8% in the single-sensor group (P = 0.001). Logistic regression showed that multi-sensor probe use was associated with reduction in EDEL with an odds ratio of 0.23 in CB ablation (P = 0.024) and 0.44 for RF ablation (P = 0.001). Esophageal luminal temperature monitoring during AFib ablation using a multi-sensor probe was associated with a significant reduction in EDEL compared to a single-sensor probe.

Catheter ablation of atrial fibrillation with a multi-electrode radiofrequency balloon; first and early two centre experience in Europe.

The Heliostar™ ablation system is a novel RF balloon ablation technology with an integrated three-dimensional mapping system. Here, we describe our early experience and procedural outcomes using this technology for atrial fibrillation catheter ablation. We sought to comprehensively assess the first 60 consecutive patients undergoing pulmonary vein isolation using the novel HELISOTAR™ RF balloon technology including procedural outcomes. A comparison of the workflow between two different anaesthetic modalities (conscious sedation [CS] vs. general anaesthesia [GA]) was made. Procedural data were collected prospectively from two high-volume centers (Barts Heart Centre, UK and University Hospital of Zurich, Zurich). A standardized approach for catheter ablation was employed. A total of 35 patients had the procedure under CS and the remaining under GA. Mean procedural and fluoroscopy times were 84 ± 33 min and 1.1 min. The median duration of RF energy application was 7 (5-9.8) mins per patient. All veins were successfully isolated, and the median isolation time was 10 (7-15) seconds. Our cohort's rate of procedural complications was low, with no mortality within 30 days postprocedure. Our early experience shows that catheter ablation using the Heliostar™ technology can be performed efficiently and safely; however, long-term data is yet to be established. Low fluoroscopy requirements, short learning curves and use of this technology with CS is possible, including the use of an oesophageal temperature probe.

Accuracy of Nasopharyngeal Temperature in Comparison to Oesophageal Temperature for Core Body Temperature Measurement: A Cross-sectional Observational Study

Introduction: Temperature monitoring intraoperatively is standard of care for almost all surgical cases and is necessary due to the important role that temperature plays in maintaining body homeostasis, anaesthetic drug metabolism, and recovery. However, invasive and user-unfriendly methods like measuring temperature in the oesophagus, tympanic membrane, or rectum have limitations. An alternative site for measuring core body temperature could be the nasopharynx, as its mucosa is supplied by branches of the internal carotid artery. Aim: To determine the accuracy of the nasopharyngeal probe in comparison to oesophageal temperature probe and to identify appropriate insertion depths for measuring core body temperature. Materials and Methods: Sixty patients scheduled for elective non-cardiac surgery under general anaesthesia lasting 60 minutes or more. A nasopharyngeal probe was inserted past the nares to a depth of 20 cm, and an oesophageal temperature probe was inserted to a depth of 40 cm past the incisors. The nasopharyngeal probe was gradually pulled out after induction, and temperatures at various depths were recorded at regular intervals. The observed depths of the nasopharyngeal probe that correlated with the oesophageal temperature were considered as the endpoints. Data was entered into Microsoft Excel and analysed using Statistical Package for Social Sciences (SPSS) version 25.0. Results: The study population consisted of 60 patients, with 31 males and 29 females, a mean age of 50 years, mean body mass index of 26 kg/m2 , American Society of Anaesthesiologists (ASA) (physical status) of 1 (n=27) and 2 (n=33). The insertion depths of 10 to 20 cm for the nasopharyngeal probe showed a mean temperature difference of ±0.3°C compared to the reference oesophageal temperature. This difference fell within the clinically acceptable accuracy range of 0 to 0.3°C (temperature mean difference ±1.96 SD) for both probes. Conclusion: The nasopharyngeal probe offers a minimally invasive method for measuring body temperature and is easily accessible for probe placement. However, the optimal depth of insertion past the nares has not been well established. Based on the results, which showed that the mean temperature difference between the two probes fell within the specified accuracy range when the nasopharyngeal probe was inserted to a depth range of 10 to 20 cm from the nares, it is advisable to use this depth range for core body temperature measurement in non cardiac surgeries.

Optimal Positioning of Nasopharyngeal Temperature Probes in Infants and Children: A Prospective Cohort Study.

The nasopharynx is an easily accessible core-temperature monitoring site, but insufficient or excessive nasopharyngeal probe insertion can underestimate core temperature. Our goal was to estimate optimal nasopharyngeal probe insertion depth as a function of age. We enrolled 157 pediatric patients who had noncardiac surgery with endotracheal intubation in 5 groups: (1) newborn to 6 months old, (2) infants 7 months to 1 year old, (3) children 13 to 23 months old, (4) children 2 to 5 years old, and (5) children 6 to 12 years old. A reference esophageal temperature probe was inserted at an appropriate depth based on each patient's height. A nasopharyngeal temperature probe was inserted from the naris at 10 cm in newborn and infants, 15 cm in children aged 1 to 5 years old, and 20 cm in children who were 6 years or older. The study nasopharyngeal probes were withdrawn 1, 2.5, or 2 cm (depending on age) 10 times at 5-minute intervals. Optimal probe insertion distances were defined by limits of agreement (LOAs) between nasopharyngeal and esophageal temperatures <0.5 °C. Optimal nasopharyngeal temperature probe position ranged from 6 to 10 cm in infants up to 6 months old, 7 to 8 cm in infants 7 to 12 months old, 7.5 to 12 cm in children 13 to 23 months old, and 10 to 12 cm in children aged 6 years and older. The 95% LOAs were <0.5 °C for all age categories except the 2- to 5-year-old group where the limits extended from -0.67 °C to 0.52 °C at 9 cm. At the optimal position within each age range, the bias (average nasopharyngeal-to-esophageal temperature difference) was ≤0.1 °C. Nasopharyngeal thermometers accurately measure core temperature, but only when probes are inserted a proper distance, which varies with age. As with much in pediatrics, nasopharyngeal thermometer insertion depths should be age appropriate.

Esophageal Protection and Temperature Monitoring Using the Circa S-Cath™ Temperature Probe during Epicardial Radiofrequency Ablation of the Pulmonary Veins and Posterior Left Atrium

Although epicardial bipolar radiofrequency ablation should diminish the risk of esophageal thermal injury in comparison to an endocardial ablation, cases of lethal atrio-esophageal fistula have been reported. To better understand this risk and to reduce the possibility of a thermal injury, we monitored the esophageal temperature with the Circa S-Cath™ temperature probe during and immediately after the ablation while implementing three procedural safety measures. Twenty patients (15 males; 63 ± 10 years) were prospectively enrolled (November 2019-February 2021). All patients underwent an epicardial ablation procedure, including an antral left and right pulmonary vein isolation with bidirectional bipolar clamping, and a roof and inferior line using unidirectional bipolar radiofrequency. Three procedural preventive mitigations were implemented: (1) transesophageal echocardiographic visualization of the atrio-esophageal interface, with probe retraction before the energy delivery; (2) lifting the ablated tissue away from the esophagus during an energy application; and (3) a 30 s cool-off and irrigation period after the energy delivery. The esophageal temperature was recorded using an insulated multisensory intraluminal esophageal temperature probe (Circa S-Cath™). Of the 20 patients enrolled, 7 patients had paroxysmal atrial fibrillation (AF), 8 persistent AF and 5 longstanding persistent AF. The average maximum luminal esophageal temperature observed was 36.2 ± 0.7 °C (34.8-38.2 °C). In our clinical experience, no abrupt increase in the luminal esophageal temperature above the baseline was observed. Since no measurements exceeded the threshold of 39 °C, no prompt interruption of energy delivery was required. Intraluminal esophageal temperature monitoring is feasible and can be helpful in confirming correct catheter position and safe energy application in bipolar epicardial left atrial ablation. Intra-procedural preventive mitigations should be implemented to reduce the risk of esophageal temperature rises.

Early results of the novel radiofrequency balloon ablation catheter for pulmonary vein isolation

Abstract Funding Acknowledgements Type of funding sources: None. Background Pulmonary vein isolation (PVI) remains the cornerstone for treating of symptomatic atrial fibrillation (AF). Single-shot PVI technologies have evolved as a standard for first-time PVI. A novel radiofrequency balloon ablation catheter is now available to offer single-shot RF pulmonary vein isolation. Purpose To summarize the early experience using the novel RF balloon ablation catheter for patients undergoing PVI in two tertiary centres in Europe. Methods We prospectively assessed the first 38 consecutive patients undergoing PVI using RF balloon ablation catheter for paroxysmal or persistent AF in two high volume centres. Both centres used a standardised approach including ultrasound-guided vascular access, uninterrupted anticoagulation, transeptal puncture via the RF balloon sheath and a limited 3D mapping software-guided LA geometry created with a circular mapping catheter. Radiofrequency application for 60s to the anterior segments and 20s posteriorly was performed in all cases, phrenic pacing was employed for ablation of right PVs. BHS performed all procedures (except 2 cases due to high BMI and severe sleep apnea) under sedation, while all patients from UHZ underwent PVI procedures with general anaesthesia as per institutional protocol. All patients had an oesophageal temperature probe to assess oesophageal temperature during ablation (passed orally under sedation) and had uninterrupted oral anticoagulation throughout the periprocedural period. Results Overall, mean age was 64±8 years, 23 (61%) were male, 24 (63%) of patients had paroxysmal AF. The majority were de novo interventions (92%). There was no significant difference between the patients demographics in the two hospitals. All veins were isolated in both groups with a total of 144 applications (n = 73 in the sedation group, n = 71 in the GA population). Median fluoroscopy time was comparable (sedation group 1.1 minutes vs GA group 1.2 minutes; P = 0.58), but median procedure time was shorter in the sedation group (65 minute vs 106 minutes; P &amp;lt; 0.001). The median number of RF ablation per patient (sedation group 7 vs GA group 9; P = 0.32) and time to isolation of each vein (sedation group 11 seconds vs GA group 10 seconds; P = 0.9) were similar. Number of acute reconnections requiring further ablations were not significantly different between groups (sedation group 11 [15%] vs GA group 14 [20%]; P = 0.96). One patient sustained transient phrenic nerve injury in the sedation group. Conclusion Our early experience shows the novel HS balloon ablation can be performed effectively, efficiently and safely under either GA or conscious sedition. The RF balloon ablation catheter paradigm lends itself to refined workflows, with low fluoroscopy requirements and a short learning curve even in initial cohorts.

Impact of very wide antral pulmonary vein isolation on esophageal temperature changes during pulsed field ablation

Abstract Funding Acknowledgements Type of funding sources: None. Background Esophageal thermal injury (ETI) is a serious drawback of available energy sources for atrial fibrillation (AF) ablation, especially on the posterior left atrial (LA) wall. Pulsed field ablation (PFA) is a novel non-thermal energy source with promising safety advantages over existing methods due to its unique myocardial tissue specificity sparing the esophagus. Objective To evaluate esophageal temperature changes during very wide antral pulmonary vein isolation (PVI) using the PFA system. Methods Thirteen consecutive AF patients (62% with paroxysmal AF; age: 61 years; 70% male) underwent first-time PFA under deep sedation. Eight pulse trains (2kV/2.5 sec, bipolar, biphasic, 4x basket/flower configuration each) were delivered to each pulmonary vein (PV). Extra pulse trains in the flower configuration were added for very wide antral circumferential ablation (vWACA). Continuous intraluminal esophageal temperature (TESO) was monitored with an S-shaped esophageal temperature probe. Results A median of 32 (IQR 32;32) and 8 (IQR 8;9) pulse trains for PVI and vWACA with a procedural time and catheter dwell time of 67 min (IQR 61-69) and 17 min (IQR 16-18) were applied. PFA with vWACA resulted in consecutive posterior LA wall isolation in 11/13 patients. Fluoroscopically, the esophagus coursed near the right PVs in 2/13, left PVs in 8/13 and mid-posterior wall position in 3/13 patients. Maximum TESO increase from baseline was 0.8 ±0.9 °C. However, no clinically relevant TESO changes occurred (Table 1). On short-term, all patients remained asymptomatic for sore throat, cough, or other symptoms potentially related to ETI. No esophago-duodenoscopy was necessary. Conclusion PFA of the PVs and lesion extension to the posterior LA wall demonstrated clinically non-significant TESO changes and has the potential to eliminate the risk of a thermal damage to the esophagus.

Comparison of ostial versus very wide antral circumferential pulmonary vein isolation using pulsed field ablation

Abstract Funding Acknowledgements Type of funding sources: None. Background Pulmonary vein isolation (PVI) is the gold standard for first-time atrial fibrillation (AF) ablation procedures. Wide antral circumferential ablation (WACA) in comparison to ostial PVI has been attributed to an improved rhythm outcome after AF ablation. Pulsed field ablation (PFA) is a novel energy source with promising safety and efficacy advantages over existing ablation methods due to its unique myocardial tissue specificity. Feasibility of PFA for very WACA has not been investigated so far. Objective To evaluate procedural characteristics and lesion formation during wide antral circumferential PVI in comparison to ostial PVI using a PFA system. Methods Thirty-seven consecutive AF patients underwent first-time PFA under deep sedation. Patients eighter received ostial (ostial group; N = 15: 66 % paroxysmal AF; age: 69 years; 66 % male) or very wide antral (vWACA group; N = 22: 59 % paroxysmal AF; age: 62 years; 73 % male) PFA. Pre and post ablation LA voltage maps were acquired using a 20-pole spiral catheter together with a 3-dimensional electroanatomic mapping system (voltage cutoff ≤0.5 mV). On post ablation maps, lesion size by encircling the ablated area was measured. In all patients, 8 pulse trains (2kV/2.5 sec, bipolar, biphasic, 4x basket/flower configuration each) were delivered to each pulmonary vein (PV). In the vWACA-group, extra pulse trains in flower configuration were added to each PV in a wide antral position continuous intraluminal esophageal temperatures (TESO) were monitored with an S-shaped esophageal temperature probe. Results A median of 8 [IQR 8;8] and 10 [IQR 10;11] pulse trains per PV for ostial and vWACA PVI were applied. vWACA PFA resulted in significant larger lesion formation (47.3 cm2 [IQR 39.1; 52.0]) in comparison to ostial PFA (35.5 cm2 [IQR 30.3; 38.1], p=0.013) with consecutive posterior LA wall isolation in 19/22 (86 %) patients (Figure 1). In the vWACA group, median TESO increased by 0.7 °C (TESOmax 36.5 °C [IQR 36.0;36.9]). However, the vWACA approach was not associated with a significant increase in procedure time, sedation dosage or exposure to radiation. Conclusion Very wide antral circumferential PFA of the PVs is feasible and was associated with significant larger lesion formation in comparison to conventional ostial PFA. Concomitant posterior LA wall isolation occurred in the majority of patient and did not result in a clinically significant increase of intraluminal esophageal temperatures, procedure time, sedation and radiation dosage.

Non-Invasive Monitoring of Core Body Temperature for Targeted Temperature Management in Post-Cardiac Arrest Care.

ImportanceAccurate monitoring of core body temperature is integral to targeted temperature management (TTM) following cardiac arrest. However, there are no reliable non-invasive methods for monitoring temperature during TTM.ObjectivesWe compared the accuracy and precision of a novel non-invasive Zero-Heat-Flux Thermometer (SpotOn™) to a standard invasive esophageal probe in a cohort of patients undergoing TTM post-cardiac arrest.Design, Setting, and ParticipantsWe prospectively enrolled 20 patients undergoing post-cardiac arrest care in the intensive care units at the London Health Sciences Centre in London, Canada. A SpotOn™ probe was applied on each patient's forehead, while an esophageal temperature probe was inserted, and both temperature readings were recorded at 1-min intervals for the duration of TTM.Main outcomes and MeasuresWe compared the SpotOn™ and esophageal monitors using the Bland–Altman analysis and the Pearson correlation, with accuracy set as a primary outcome. Secondary outcomes included precision and correlation. Bias exceeding 0.1°C and limits of agreement exceeding 0.5°C were considered clinically important.ResultsSixteen (80%) of patients had complete data used in the final analysis. The median (interquartile range) duration of recording was 38 (12–56) h. Compared to the esophageal probe, SpotOn™ had a bias of 0.06 ± 0.45°C and 95% limits of agreement of −0.83 to 0.95°C. The Pearson correlation coefficient was 0.97 (95% confidence interval 0.9663–0.9678), with a two-tailed p < 0.0001.Conclusion and RelevanceThe SpotOn™ is an accurate method that may enable non-invasive monitoring of core body temperature during TTM, although its precision is slightly worse than the predefined 0.5°C when compared to invasive esophageal probe.

Evaluation of the Temple Touch Pro™ noninvasive core-temperature monitoring system in 100 adults under general anesthesia: a prospective comparison with esophageal temperature

Perioperative hypothermia is still common and has relevant complication for the patient. An effective perioperative thermal management requires essentially an accurate method to measure core temperature. So far, only one study has investigated the new Temple Touch Pro™ (Medisim Ltd., Beit-Shemesh, Israel). during anesthesia Therefore, we assessed the agreement between the Temple Touch Pro™ thermometer (TTP) and distal esophageal temperature (TEso) in a second study. After approval by the local ethics committee we studied 100 adult patients undergoing surgery with general anesthesia. Before induction of anesthesia the TTP sensor unit was attached to the skin above the temporal artery. After induction of anesthesia an esophageal temperature probe was placed in the distal esophagus. Recordings started 10 min after placement of the esophageal temperature probe to allow adequate warming of the probes. Pairs of temperature values were documented in five-minute intervals until emergence of anesthesia. Accuracy of the two methods was assessed by Bland-Altman comparisons of differences with multiple measurements. Core temperatures obtained with the TTP in adults showed a mean bias of -0.04 °C with 95% limits of agreement within − 0.99 °C to + 0.91 °C compared to an esophageal temperature probe. We consider the TTP as a reasonable tool for perioperative temperature monitoring. It is not accurate enough to be used as a reference method in scientific studies, but may be a useful tool especially for conscious patients undergoing neuraxial anesthesia or regional anesthesia with sedation.Trial registration This study was registered in the German Clinical Trials Register (DRKS-ID: 00024050), day of registration 12/01/2021.

Perioperative targeted temperature management of severely burned patients by means of an oesophageal temperature probe

BackgroundHypothermia in severely burned patients is associated with a significant increase in morbidity and mortality. The use of an oesophageal heat exchanger tube (EHT) can improve perioperative body temperatures in severely burned patients. The aim of this study was to investigate the intraoperative warming effect of oesophageal heat transfer in severe burn patients. MethodsSingle-centre retrospective study performed at the Burns Centre of the University Hospital Zurich. Between January 2020 and May 2021 perioperative temperature management with EHT was explored in burned patients with a total body surface area (TBSA) larger than 30%. Data from patients, who received perioperative temperature management by EHT, were compared to data from the same patients during interventions performed under standard temperature management matching for length and type of intervention. ResultsA total of 30 interventions (15 with and 15 without EHT) in 10 patients were analysed. Patient were 38 [26−48] years of age, presented with severe burns covering a median of 50 [42−64] % TBSA and were characterized by an ABSI of 10 [8−12] points. When receiving EHT management patients experienced warming at 0.07 °C per minute (4.2 °C/h) compared to a temperature loss of − 0.03 °C per minute (1.8 °C/h) when only receiving standard temperature management (p < 0.0001). No adverse or serious adverse events were reported. ConclusionThe use of an oesophageal heat transfer device was effective and safe in providing perioperative warming to severely burned patients when compared to a standard temperature management protocol. By employing an EHT as primary temperature management device perioperative hypothermia in severely burned patients can possibly be averted, potentially leading to reduced hypothermia-associated complications.

Novel Measurement Approaches Are Needed In The Pre-Hospital Setting To Prevent Accidental Hypothermia.

Accidental hypothermia can be fatal if not recognised early, and effective management relies on the accurate recording of core body temperature. The focus of this critique - a recent study by Podsiado et al. (2019) – highlighted the need for reliable measurement of core body temperature in the pre-hospital and austere setting. An esophageal temperature probe may prove to be a reliable, and best practice approach for measuring core body temperature in critically unwell, unconscious patients suffering accidental hypothermia.

Preventing esophageal complications from atrial fibrillation ablation: A review.

Atrioesophageal fistula is a life-threatening complication of ablation treatment for atrial fibrillation. Methods to reduce the risk of esophageal injury have evolved over the last decade, and diagnosis of this complication remains difficult and therefore challenging to treat in a timely manner. Delayed diagnosis leads to treatment occurring in the context of a critically ill patient, contributing to the poor prognosis associated with this complication. The associated mortality risk can be as high as 70%. Recent important advances in preventative techniques are explored in this review.Preventative techniques used in current clinical practice are discussed, which include high-power short-duration ablation, esophageal temperature probe monitoring, cryotherapy and laser balloon technologies, and use of proton pump inhibitors. A lack of randomized clinical evidence for the effectiveness of these practical methods are found. Alternative methods of esophageal protection has emerged in recent years, including mechanical deviation of the esophagus and esophageal temperature control (esophageal cooling). Although these are fairly recent methods, we discuss the available evidence to date. Mechanical deviation of the esophagus is due to undergo its first randomized study. Recent randomized study on esophageal cooling has shown promise of its effectiveness in preventing thermal injuries. Lastly, novel ablation technology that may be the future of esophageal protection, pulsed field ablation, is discussed.The findings of this review suggest that more robust clinical evidence for esophageal protection methods is warranted to improve the safety of atrial fibrillation ablation.