P1861Influence of thermal conductivity on esophageal protection with a cooling device during high-power short-duration radiofrequency ablation

2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
E Kulstad ◽  
M Mercado-Montoya ◽  
S Shah
Keyword(s):  
Thermal Conductivity ◽  
Short Duration ◽  
High Power ◽  
Operating Conditions ◽  
Whole Body ◽  
Esophageal Injury ◽  
Cooling Power ◽  
Protective Effects ◽  
Rf Ablation ◽  
Cooling Device

Abstract Introduction Recent clinical data show that high-power, short-duration (HPSD) radiofrequency (RF) ablation can result in a similar esophageal injury rate as traditional low-power, long-duration (LPLD) ablation. Existing methods to prevent esophageal injury have yielded mixed results and can result in prolonged procedure time, potentially increasing the incidence of post-operative cognitive dysfunction. A new esophageal cooling device currently available for whole-body temperature modulation is being studied for the prevention of esophageal injury during LPLD RF ablation and cryoablation. We sought to develop a mathematical model of HPSD ablation in order to quantify the capability of this new esophageal cooling device to protect from esophageal injury under high-power conditions. Methods Using a model we developed of HPSD RF ablation in the left atrium, we measured the change in esophageal lesion formation and the depth of lesions (measured as percent transmurality) with the esophageal cooling device in place and operating at a temperature from 5°C to 37°C. Tissue parameters, including thermal conductivity, were set to average values obtained from existing literature, and energy settings were evaluated at 50W for between 5 and 10 seconds, and at 90W for a duration of 4 seconds. Results Esophageal injury as measured by percent transmurality was considerably higher at 50W and 10s duration than at 90W of power with 4s duration, although both settings showed potential for esophageal injury. The protective effect of the esophageal cooling device was evident for both cases, with a greater effect when using 50W for 10s (Figure 1). At the coldest device settings, using a 5 min pre-cooling period also reduced the transmurality of the intended atrial lesions. Esophageal protection in HPSD ablation Conclusions Esophageal cooling with a new patient temperature management device shows protective effects against thermal injury during RF ablation across a range of tissue thermal conductivity, using a variety of high-power settings, including 90W applied for 4 seconds. Adjusting the cooling power by adjusting the circulating water temperature in the device allows for a tailoring of the protective effects to operating conditions. Acknowledgement/Funding Attune Medical

P1379Fluoroscopy requirement reduction using an esophageal cooling protocol during left atrial ablation

EP Europace ◽  
2020 ◽  
Vol 22 (Supplement_1) ◽  
Author(s):  
J Zagrodzky ◽  
S Bailey ◽  
S Shah ◽  
E Kulstad
Keyword(s):  
Fluoroscopy Time ◽  
Esophageal Injury ◽  
Rf Ablation ◽  
Cooling Device ◽  
Atrial Ablation ◽  
Single Sensor ◽  
The Difference ◽  
Sensor Temperature ◽  
Time Required ◽  
Cold Liquid

Abstract Background Ablation of the left atrium with radiofrequency (RF) energy is associated with some risks to the esophagus.  Cooling the esophagus has been used as one approach to reducing esophageal injury, most commonly with direct instillation of cold liquid via gastric tube placed in the esophagus.  A new esophageal cooling device avoids the risks of free liquid instillation by using a closed-loop system, and avoids the need for frequent repositioning or stopping of the procedure often required when utilizing luminal esophageal temperature (LET) monitoring.  This in turn may reduce fluoroscopy requirements for the procedure. Purpose Measure the difference in fluoroscopy time required during RF ablation using an esophageal cooling device protocol, and compare this to standard LET monitoring using single or multi-sensor temperature probes. Methods We obtained total fluoroscopy time per patient from records of RF ablation procedures performed by a two operators over a 12 month period.  We compared fluoroscopy times between patients treated with an esophageal cooling device to control patients who were treated with LET monitoring using either single-sensor or multi-sensor temperature probes. Results Fluoroscopy times were available for a total of 179 patients treated with an esophageal cooling device, and 118 patients treated with LET monitoring over the 12 month study period.  Mean fluoroscopy time for patients treated with esophageal cooling was 4.0 minutes (SD 4.9 minutes) with a median of 2.0 minutes (IQR 1.3 to 3.8 minutes).  Mean fluoroscopy time for patients undergoing LET monitoring was 5.5 minutes (SD 5.7 minutes) with a median of 3.0 minutes (IQR 1.9 to 8.4 minutes).  This difference represents a 27% reduction in mean fluoroscopy time, and a 33% reduction in median fluoroscopy time in the esophageal cooling group (p<.001, Mann-Whitney U test). Conclusions  Fluoroscopy requirements were reduced by 27% with an esophageal cooling device when compared to standard LET monitoring.

scholarly journals Thermal and electric Characteristics of High-power Short-duration Radiofrequency Ablation and Standard Radiofrequency Ablation: A Computer Simulation Study

2021 ◽  
Author(s):  
Kaihao Gu ◽  
Shengjie Yan ◽  
Xiaomei Wu
Keyword(s):  
Radiofrequency Ablation ◽  
Short Duration ◽  
High Power ◽  
Lesion Size ◽  
Lesion Volume ◽  
Rf Ablation ◽  
Thermal Lesion ◽  
Lesion Depth ◽  
Lesion Diameter ◽  
Rate Of Increase

Abstract Background: High power-short duration ablation is an emerging conception for cardiac RF treatment. But the biophysical ablation properties of this technique have not been fully explored. This study compared the electric field characteristics and thermal lesion dimension in High power-short duration (HP-SD) radio frequency (RF) ablation and standard RF ablation by using the finite element method. Results: The results demonstrated that the lesion size and temperature in HP–SD RF ablation increased faster than standard RF ablation. The thermal lesion volume in both ablation modes demonstrated a linear increase and the rate of increase of HP–SD RF ablation grew faster than that of standard RF ablation. For HP–SD application at 50 W for 5 s, the lesion depth was shallower (1.74 to 2.1 mm vs 2.40 to 3.15 mm) and the surface lesion diameter was broader (2.76 to 3.32 mm vs 2.42 to 2.66 mm) than that for standard RF ablation at 25 W for 30 s. Conclusion: Compared with standard RF ablation, HP–SD RF ablation creates a broader lesion width and surface lesion diameter but shallower lesion depth, with a faster increase in temperature. HP–SD ablation is more able to achieve uniform and contiguous lesion shape, which is a suitable for point-to-point RF ablation procedures.Higher temperature was formed in deeper space of cardiac tissue in HP–SD ablation. The duration of HP–SD ablation should be strictly controlled for preventing the steam occur in tissue.

Impact of High-Power Short-Duration Radiofrequency Ablation on Esophageal Temperature Dynamic

2021 ◽  
Author(s):  
Hagai D. Yavin ◽  
Zachary P. Bubar ◽  
Koji Higuchi ◽  
Jakub Sroubek ◽  
Mohamed Kanj ◽  
...  
Keyword(s):  
Radiofrequency Ablation ◽  
Pulmonary Vein ◽  
Short Duration ◽  
Pulmonary Vein Isolation ◽  
High Power ◽  
Temperature Rise ◽  
Esophageal Injury ◽  
Esophageal Temperature ◽  
Dynamic Profile ◽  
Temperature Dynamic

Background: High-power short-duration (HP-SD) radiofrequency ablation (RFA) has been proposed as a method for producing rapid and effective lesions for pulmonary vein isolation. The underlying hypothesis assumes an increased resistive heating phase and decreased conductive heating phase, potentially reducing the risk for esophageal thermal injury. The objective of this study was to compare the esophageal temperature dynamic profile between HP-SD and moderate-power moderate-duration (MP-MD) RFA ablation strategies. Methods: In patients undergoing pulmonary vein isolation, RFA juxtaposed to the esophagus was delivered in an alternate sequence of HP-SD (50 W, 8–10 s) and MP-MD (25 W, 15–20 s) between adjacent applications (distance, ≤4 mm). Esophageal temperature was recorded using a multisensor probe (CIRCA S-CATH). Temperature data included magnitude of temperature rise, maximal temperature, time to maximal temperature, and time return to baseline. In swine, a similar experimental design compared the effect of HP-SD and MP-MD on patterns of esophageal injury. Results: In 20 patients (68.9±5.8 years old; 60% persistent atrial fibrillation), 55 paired HP-SD and MP-MD applications were analyzed. The esophageal temperature dynamic profile was similar between HP-SD and MP-MD ablation strategies. Specifically, the magnitude of temperature rise (2.1 °C [1.4–3] versus 2.0 °C [1.5–3]; P =0.22), maximal temperature (38.4 °C [37.8–39.3] versus 38.5 °C [37.9–39.4]; P =0.17), time to maximal temperature (24.9±7.5 versus 26.3±6.8 s; P =0.1), and time of temperature to return to baseline (110±23.2 versus 111±25.1 s; P =0.86) were similar between HP-SD and MP-MD ablation strategies. In 6 swine, esophageal injury was qualitatively similar between HP-SD and MP-MD strategies. Conclusions: Esophageal temperature dynamics are similar between HP-SD and MP-MD RFA strategies and result in comparable esophageal tissue injury. Therefore, when using a HP-SD RFA strategy, the shorter application duration should not prompt shorter intervals between applications.

In silico analysis of the relation between conventional and high‐power short‐duration RF ablation settings and resulting lesion metrics

2020 ◽  
Vol 31 (6) ◽  
pp. 1332-1339 ◽  
Author(s):  
Felix Bourier ◽  
Konstantinos Vlachos ◽  
Antonio Frontera ◽  
Claire A. Martin ◽  
Anna Lam ◽  
...  
Keyword(s):  
Short Duration ◽  
High Power ◽  
In Silico ◽  
In Silico Analysis ◽  
Rf Ablation ◽  
Silico Analysis

scholarly journals Characteristics of Esophageal Injury in Ablation of Atrial Fibrillation Using a High-Power Short-Duration Setting

2020 ◽  
Vol 13 (10) ◽  
Author(s):  
Takashi Kaneshiro ◽  
Masashi Kamioka ◽  
Naoko Hijioka ◽  
Shinya Yamada ◽  
Tetsuro Yokokawa ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Left Atrium ◽  
Pulmonary Vein ◽  
Short Duration ◽  
Pulmonary Vein Isolation ◽  
High Power ◽  
Thermal Injury ◽  
Low Voltage ◽  
Conventional Group ◽  
Esophageal Injury

Background: The mechanism of esophageal thermal injury (ETI; esophageal mucosal injury and periesophageal nerve injury leading to gastric hypomotility) remains unknown when using a high-power short-duration (HP-SD) setting. This study sought to evaluate the characteristics of esophageal injuries in atrial fibrillation ablation using a HP-SD setting. Methods: After exclusion of 5 patients with their esophagus at the right portion of left atrium and 21 patients with additional ablations such as box isolation and low voltage area ablation in left atrium posterior wall, 271 consecutive patients (62±10 years, 56 women) who underwent pulmonary vein isolation by radiofrequency catheter ablation were analyzed. In the 101 patients, a HP-SD setting at 45 to 50 W with an Ablation Index module was used (HP-SD group). In the remaining 170 patients before introduction of the HP-SD setting, a conventional power setting of 20 to 30 W with contact force monitoring was used (conventional group). We performed esophagogastroduodenoscopy after pulmonary vein isolation in all patients and investigated the incidence and characteristics of ETI. Results: Although the incidence of ETI was significantly higher in the HP-SD group compared with the conventional group (37% versus 22%, P =0.011), the prevalence of esophageal lesions did not differ between the groups (7% versus 8%). Multivariate logistic regression analysis revealed that the use of the HP-SD setting (odds ratio, 6.09, P <0.001), and the parameters that suggest anatomic proximity surrounding the esophagus, were independent predictors of ETI. However, the majority of ETI in the HP-SD group was gastric hypomotility, and the thermal injury was limited to the shallow layer of the periesophageal wall using the HP-SD setting. Conclusions: Although the use of the HP-SD setting was a strong predictor of ETI, it could avoid deeper thermal injuries that reach the esophageal mucosal layer.

P565First characterization of high-power short-duration radiofrequency ablation with remote magnetic navigation assistance

EP Europace ◽  
2020 ◽  
Vol 22 (Supplement_1) ◽  
Author(s):  
G Caluori ◽  
E Odehnalova ◽  
J Krenek ◽  
T Jadczyk ◽  
M Pesl ◽  
...  
Keyword(s):  
Short Duration ◽  
High Power ◽  
Calibration Curve ◽  
Left Ventricular ◽  
Right Atrial ◽  
Pathological Examination ◽  
Magnetic Navigation ◽  
Rf Ablation ◽  
Remote Magnetic Navigation

Abstract Funding Acknowledgements MEYS- CR (ref#LQ1605 and LM2015062) Background/Introduction High-power short-duration (HPSD) radiofrequency (RF) ablation relies on the application of intense thermal fields for a carefully restricted time, in order to quickly obtain deep but precise lesions that spare the structures surrounding the heart. The approach is still under evaluation across different therapies and catheter technologies. To the present day there is no available characterization of HPSD ablation supported by remote magnetic navigation (RMN). Purpose To describe the safety issues regarding HPSD ablation in atria and ventricles with RMN systems, while characterizing the thermal lesion size and continuity in an acute closed-chest swine model. Methods The animal trial was divided in two arms (left ventricular and atrial). 10 female large white pigs (6-month-old weight 55-65 kg) were employed in each arm. Endocardial electroanatomical mapping and ablation were performed with RMN assistance to provide stable contact and flexible maneuvering. The ventricular cohort was divided in 5 power settings (30-40-50-60-70W). Multiple RF applications (10 ca./animal) were delivered until a pop occurred or up to 60s. In the atrial cohort the animals were divided by a combination of power/application time (50W/20s – 70W/10s – 90W/4s). Intracaval right atrial ablation lines and postero-lateral left atrial lines were performed in a point-by-point fashion (ca. 4mm distance). Irrigation rate was 30ml/min. The ventricular lesions were measured via software after 9.4T MRI of fixed hearts. The atrial lesions were measures during pathological examination after explanation. Results In the ventricular arm, we obtained a safety calibration curve linking the imposed power setting to the maximal time of application. The time before a pop decreased non-linearly from 60s down to 17.69 ± 8.21 s at 70W. No statistically significant differences were observed when comparing lesions depth, width and volume among the selected power settings. In the atrial arm we observed on the post-ablation maps a significant decrease of intracaval lesions (i.e. area with bipolar voltage &lt;1.5mV) width (17.57 ± 1.89 mm for 50W/4s down to 10.16 ± 1.56 mm for 90W/4s). Pericardial, pleural and aortic damages were visible across all the employed settings, with less pronounced alterations for 90W/4s. Transmural lesions were visible both on the right and left atrium, with evident gaps for 50W/20s. Conclusion The presented work assesses for the first time the safety limits of HPSD ablation on healthy ventricular myocardium. We provide a calibration curve for faster RF ablation with comparable lesion features. Furthermore, we expanded the previously reported application in the atrium adding the benefits of stable controlled contact provided by RMN systems. We highlighted the benefits (e.g. faster, continuous and localized lesion formation) and risks for peripheral structures using HPSD ablation for supraventricular tachycardia interventions. Abstract Figure.

scholarly journals High-power, short-duration ablation in the coronary sinus: clinical cases and preliminary observations on swine hearts

2021 ◽  
Author(s):  
Chengming Ma ◽  
Xiaomeng Yin ◽  
Yunlong Xia ◽  
Jiao Sun ◽  
Shiyu Dai ◽  
...  
Keyword(s):  
Short Duration ◽  
Coronary Sinus ◽  
High Power ◽  
Total Duration ◽  
Alternative Strategy ◽  
Rf Ablation ◽  
Coronary Sinus Ostium ◽  
Long Duration ◽  
Clinical Cases

Abstract Purpose Coronary sinus-related arrhythmias are common; however, it is difficult to perform radiofrequency (RF) ablation at these sites efficiently and safely. High-power, short-duration ablation (HPSD) is a proven alternative strategy for pulmonary vein isolation (PVI); whether it can be applied to ablation of the coronary sinus is unknown. The purpose of this preliminary study was to evaluate the feasibility and safety of HPSD ablation in the coronary sinus. Methods Firstly, we demonstrated 4 clinical cases of 3 types of arrhythmias who had unsuccessful ablation with standard power initially, but received successful ablations with HPSD. Secondly, RF ablation was performed in the coronary sinus ostium (CSO) and middle cardiac vein (MCV) of 4 in vitro swine hearts. Two protocols were compared: HPSD (45 W/5 S×5 rounds) and a conventional strategy that used low-power, long-duration ablation (LPLD: 25 W/10 S ×5 rounds). The total duration of HPSD protocol was 25 s, and which of LPLD was 50 s. Results A total of 28 lesions were created. HPSD can produce longer, wider, deeper, and larger lesions than LPLD. This difference was more pronounced when the ablation was in the MCV. One instance of steam pop occurred during LPLD in the MCV. Conclusions HPSD is an effective alternative strategy for ablation in coronary sinus according to clinical applications and preliminary animal study. However, the safety needs to be further evaluated based on more animal and clinical studies.

Very high-power short-duration temperature-controlled ablation for pulmonary vein isolation: The Fast-and-Furious study

EP Europace ◽  
2021 ◽  
Vol 23 (Supplement_3) ◽  
Author(s):  
CH Heeger ◽  
MS Sano ◽  
RMS Meyer-Saraei ◽  
CE Eitel ◽  
HL Phan ◽  
...  
Keyword(s):  
Pulmonary Vein ◽  
Short Duration ◽  
Pulmonary Vein Isolation ◽  
High Power ◽  
The Novel ◽  
Rf Ablation ◽  
Procedure Time ◽  
Ablation Catheter ◽  
Temperature Controlled ◽  
Very High

Abstract Funding Acknowledgements Type of funding sources: None. Background Catheter ablation for atrial fibrillation (AF) treatment provides effective and durable PVI associated with encouraging clinical outcome. The novel QDot ablation catheter with Qmode + ablation mode (90W/4sec, Figure 1) offers the ability to possibly improve safety and decrease ablation procedure times. Aims We aim to evaluate safety and efficacy of the very high-power short-duration (vHP-SD) temperature-controlled radiofrequency (RF) ablation Qmode + mode for pulmonary vein isolation (PVI) utilizing the novel QDot micro ablation catheter. The data was compared to conventional power-controlled ablation index (AI) guided PVI. Methods Twenty-five consecutive patients with paroxysmal or persistent AF were prospectively enrolled, underwent vHP-SD based PVI (vHP-SD group) and were compared to 25 consecutive patients treated with conventional CF-sensing catheters (control). Results All PVs were successfully isolated utilizing Qmode +. The total median RF ablation time was vHP-SD: 334 (282, 369) sec. vs control: 1567 (1250, 1756) sec. (p &lt; 0.0001), the median procedure time was vHP-SD: 56 (48-62) vs. control: 104 (92-122) min (p &lt; 0.0001). No differences in periprocedural complications were observed. Conclusions The novel Qmode + provides safe and effective PVI with impressive short RF time and short procedures times. Procedure time and RF time were substantial lower in the vHP-SD group. Abstract Figure 1

scholarly journals A novel local impedance algorithm and contact force sensing to guide high power short duration radiofrequency ablation is efficient and safe for circumferential pulmonary vein isolation

EP Europace ◽  
2021 ◽  
Vol 23 (Supplement_3) ◽  
Author(s):  
J Schreieck ◽  
D Heinzmann ◽  
C Scheckenbach ◽  
M Gawaz ◽  
M Duckheim
Keyword(s):  
Radiofrequency Ablation ◽  
Pulmonary Vein ◽  
Short Duration ◽  
Contact Force ◽  
High Power ◽  
Force Sensing ◽  
The Novel ◽  
Rf Ablation ◽  
Af Ablation ◽  
Circumferential Pulmonary Vein Isolation

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Local impedance (LI) drop can predict sufficient lesion formation during radiofrequency ablation (RF). Recently, a novel ablation catheter technology able to measure LI and contact force has been made available for clinical use. High power short duration (HPSD) RF ablation has been shown to be feasible for atrial fibrillation (AF) ablation with short procedure time. We used LI drop and plateau formation to guide duration of 50 Watt RF power applications for circumferential pulmonary vein isolation (PVI). Methods Consecutive patients with indication for de novo AF ablation (n = 32, age 65 ± 10 years) with paroxysmal (n = 16) or persistent (n = 16) AF underwent ultra high density 3D mapping of the left atrium and catheter ablation. Thereafter, ipsilateral PV encircling with 50 Watt RF-applications targeting an interlesion distance of ≤ 6mm and a contact force of 10-30g was performed. Duration of HPSD RF application between 7-15s was guided by impedance drop &gt;20 Ohm and plateau formation of LI. Further ablation strategy was left to the investigator’s discretion. Esophageal temperature measurement was performed using a three thermistor catheter with temperature cut off 39.0°C. In case of temperature rise or very near esophageal contact to the circumferential line, RF application time was shortened to 7s. Patients underwent adenosine testing after PVI. Previously we performed all types of AF ablation using an LI guided HPSD ablation without contact force measurement capability in 80 patients. Results Complete PVI was achieved in all pts with only 13.5 ± 4.3 min cumulative RF application duration and an ablation procedure duration of 46.5 ± 10.4 min with the novel LI measuring catheter. First-pass isolation of ipsilateral veins was achieved in 75% of circles. Recurrence of PV conduction during waiting period (20min) and adenosine testing occured in 25% of circles, and was reablated in most patients with a single spot of HPSD application. Using 94 ± 36 RF application per patient, mean maximum LI drop was 23.6 ± 4.0 Ohm. Reconnected fibers were associated with low LI drop due to instability of contact in most cases due to breathing in case of difficult sedation of the patients. No serious complications occurred in all 32 pts using HPSD with the novel contact force catheter design. Conclusion Guiding of HPSD RF ablation by LI is highly efficient and safe. A novel local impedance algorithm in combination with contact force sensing enable short PVI times with low early recurrence of PV conduction. Prediction of permanent lesions seems possible and the only limitation seems to be unstable RF catheter contact due patients breathing. Follow up have to be waited.

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