P4763High power radiofrequency ablation with fixed short duration is rapid, efficient and safe for circumferential pulmonary vein isolation

2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
J Schreieck ◽  
M Duckheim ◽  
U Yurtbil ◽  
J Flassak ◽  
C Scheckenbach ◽  
...  
Keyword(s):  
Left Atrium ◽  
Short Duration ◽  
Temperature Rise ◽  
Posterior Wall ◽  
Rf Ablation ◽  
Esophageal Temperature ◽  
Single Spot ◽  
Rf Applications ◽  
Circumferential Pulmonary Vein Isolation

Abstract Background Short duration 50 Watt radiofrequency (RF) ablation has been shown to be feasible for atrial fibrillation (AF) ablation with short procedure times. Purpose We evaluated 50 Watt RF power with a different fixed short application duration at the anterior and posterior left atrial wall using contact force (CF) sensing catheters for circumferential pulmonary vein isolation (PVI). Methods Consecutive patients (pts) with indication for de novo AF ablation (n=40, age 64±12 years) with paroxysmal (n=23) or persistent (n=17) AF underwent high density 3D mapping of the left atrium. Low voltage areas of more than 5% of the left atrium were only found in 20% of pts. Thereafter, circumferential PVI using CF sensing catheters was performed. For each RF application (50 Watt, RF duration 11–13s at the anterior wall, 9–11s at the posterior wall) a stable catheter tip position with minimal mean CF of 3g was required and application was stopped in case of CF more than 30g. Esophageal temperature measurement was performed with temperature cut off 39.0°C. In case of temperature rise, ablation protocol was switched to conventional 20 Watt RF applications for ablation adjacent to the esophagus. Results Complete PVI was achieved in all pts with 81±29 short RF applications resulting in cumulative RF applications duration of 13.1±4.2min and an ablation duration of 59±17min for complete PVI. Even RF application with low CF (3–5g) were effective. Due to esophageal temperature rise, switch to conventional RF application with 20 Watt was performed in 43% of pts at least at one posterior PV entrance. After a waiting period of 20 min only in 33% of pts any PV conduction recurs, in 28% of pts only at a single spot and reconnected fibers were not associated with low CF application at that spot, but clearly associated with low energy application at the posterior wall. All PV were successfully re-isolated in most of pts with a single spot high energy RF application. No serious complications occurred in association with PVI. Follow up will be available at presentation time. Conclusion RF ablation with 50 Watt fixed short duration is efficient and safe for circumferential PVI. Ablation procedure durations are shorter and early recurrence rates are lower compared to reported conventional ablation procedures. The importance of CF titration seems to be diminished by 50 Watt RF applications in the left atrium. Further follow up have to be waited.

scholarly journals Power, Lesion Size Index and Oesophageal Temperature Alerts During Atrial Fibrillation Ablation

2020 ◽  
Vol 13 (10) ◽  
Author(s):  
Milena Leo ◽  
Michala Pedersen ◽  
Kim Rajappan ◽  
Matthew R. Ginks ◽  
Ross J. Hunter ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Left Atrium ◽  
Pulmonary Vein ◽  
Recurrence Rate ◽  
Posterior Wall ◽  
Lesion Size ◽  
Atrial Fibrillation Recurrence ◽  
Esophageal Temperature ◽  
Size Index

Background: Low radiofrequency powers are commonly used on the posterior wall of the left atrium for atrial fibrillation ablation to prevent esophageal damage. Compared with higher powers, they require longer ablation durations to achieve a target lesion size index (LSI). Esophageal heating during ablation is the result of a time-dependent process of conductive heating produced by nearby radiofrequency delivery. This randomized study was conducted to compare risk of esophageal heating and acute procedure success of different LSI-guided ablation protocols combining higher or lower radiofrequency power and different target LSI values. Methods: Eighty consecutive patients were prospectively enrolled and randomized to one of 4 combinations of radiofrequency power and target LSI for ablation on the left atrium posterior wall (20 W/LSI 4, 20 W/LSI 5, 40 W/LSI 4, and 40 W/LSI 5). The primary end point of the study was the occurrence and number of esophageal temperature alerts per patient during ablation. Acute indicators of procedure success were considered as secondary end points. Long-term follow-up data were also collected for all patients. Results: Esophageal temperature alerts occurred in a similar proportion of patients in all groups. Significantly, shorter radiofrequency durations were required to achieve the target LSI in the 40 W groups. Less than 50% of the radiofrequency lesions reached the target LSI of 5 when using 20 W despite a longer radiofrequency duration. A lower rate of first-pass pulmonary vein isolation and a higher rate of acute pulmonary vein reconnection were recorded in the group 20 W/LSI 5. A lower atrial fibrillation recurrence rate was observed in the 40 W groups compared with the 20 W groups at 29 months follow-up. Conclusions: When guided by LSI, posterior wall ablation with 40 W is associated with a similar rate of esophageal temperature alerts and a lower atrial fibrillation recurrence rate at follow-up if compared with 20 W. These data will provide a basis to plan future randomized trials. Registration: URL: https://www.clinicaltrials.gov . Unique identifier: NCT02619396.

scholarly journals CATHETER ABLATION FOR ATRIAL FIBRILLATION USING THE ABLATION INDEX-HIGH POWER STRATEGY. Do we have the ideal target?

2021 ◽  
Author(s):  
oluwaseun adeola ◽  
asad Al Aboud ◽  
Travis Richardson ◽  
Gregory Michaud
Keyword(s):  
Atrial Fibrillation ◽  
Catheter Ablation ◽  
High Power ◽  
Posterior Wall ◽  
Comparable Efficacy ◽  
Rf Ablation ◽  
Total Procedure Time ◽  
Ablation Index ◽  
Evaluation Feedback

Pulmonary vein isolation (PVI) is the cornerstone of catheter ablation for atrial fibrillation (AF) However AF recurrence after a single ablation procedure is common and often attributed to ineffective lesion delivery during PVI. In this issue of the Journal of Cardiovascular Electrophysiology, Chen et al reported their experience with 122 patients who underwent an ablation index-high power (AI-HP) strategy RF ablation for AF using 50W power, targeting AI values of 550 on the anterior left atrium (LA), 400 on the posterior wall and inter-lesion distance (ILD) 6mm. They achieved 1st pass PVI in 96.7% of cases, mean RF time was 11.5min and total procedure time was only 55.8min. All patients had 72h-Holter monitor and trans-telephonic follow up. They reported 89.4% arrhythmia free survival among patients with paroxysmal AF and 80.4% among patients with persistent AF at 15-month follow up. Sixty (49%) patients had luminal esophageal temperature (LET) >390C out of which 3 (2.5%) had asymptomatic endoscopic esophageal erosions/erythema. Four (3%) patients had clinically apparent steam pops during ablation with no adverse clinical sequela. While AI-HP guided RF ablation may be an attractive strategy for PVI that likely reduces procedure times and probably has comparable efficacy to conventional ablation settings, its safety requires further evaluation. Feedback from the ablated tissue may need to be incorporated into optimized ablation energy parameters to further improve outcomes.

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.

A novel local impedance algorithm to guide effective pulmonary vein isolation in AF patients: 1-year outcome from the CHARISMA Study

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
L Segreti ◽  
A De Simone ◽  
V Schillaci ◽  
G Zucchelli ◽  
C Pandozi ◽  
...  
Keyword(s):  
Time Course ◽  
De Novo ◽  
Holter Monitoring ◽  
Rf Ablation ◽  
Tissue Impedance ◽  
Local Tissue ◽  
Spot Center ◽  
Rf Applications ◽  
Tissue Characteristics

Abstract Background Recently, a novel technology able to measure local tissue impedance (LI) providing a measure of tissue characteristics aimed at validating confidently ablation endpoints has become available for clinical use. Purpose We report the outcomes of our acute and long-term clinical evaluation of this algorithm in consecutive atrial fibrillation ablation cases. Methods Consecutive patients (pts) undergoing AF ablation at 6 Italian centers were included in the CHARISMA registry. A novel RF ablation catheter and a dedicated algorithm were used to measure LI through the distal catheter's electrode. The ablation was guided by looking at the magnitude and time course of impedance drop during RF delivery. The maximum distance between each ablation spot (center-to-center) was suggested to be ≤4 mm. RF applications were targeted to a LI drop of 10 Ω and RF applications were stopped when a maximum cutoff LI drop of <40 Ω was observed. Successful single RF ablation was defined according with a reduction of signal voltage (RedV) by at least 50% and inability to capture local tissue on pacing. Ablation endpoint was PVI as assessed by entrance and exit block. Post-ablation, all pts were monitored with ambulatory event monitoring, as well as Holter monitoring at 3, 6, and 12 months post-ablation. Additional ECG monitoring was performed as indicated by patient symptoms. Results A total of 1914 point by point first pass RF applications >10 s performed around PVs were analyzed from 98 pts (mean age = 61±11 years, 69% male, 55% paroxysmal AF, 45% persistent AF, 60% de novo procedures, 40% redo procedures). The mean LI was 105±15Ω prior to ablation and 92±13Ω after ablation (p<0.0001, mean absolute LI drop of 12.7±8Ω) during a median RF delivery time of 22 [17–31] sec. Effective ablation spots (88%) showed a higher absolute impedance drop (13.6±8Ω at effective RedV vs 6±3Ω at ineffective RedV, p<0.0001) compared with ineffective sites (12%). No steam pops or complications, including atrio-esophageal fistula or tamponade were reported during or after the procedures. At the end of the procedures all PVs were successfully isolated in all study pts. During a median follow-up of 369 [287–446] days, 13 pts (13.2%) developed an AF/AT recurrence after the 90-days blanking period (9.2% with paroxysmal vs 18% with persistent AF, p=0.239; 8.5% for de novo vs 20.5% for redo procedures, p=0.127). The time to recurrence was comparable among AF type (HR=1.97; 0.66 to 5.86; log-rank p=0.2265 for persistent vs paroxysmal AF) and procedural type (HR=2.56; 0.84 to 7.82; log-rank p=0.087 for redo vs de novo procedure) Conclusions In our experience, the magnitude of the LI drop during RF delivery was associated with effective lesion formation. An ablation strategy for PVI guided by LI technology was safe and effective, and resulted in a very low recurrence rate of AF at 1-year follow-up irrespective of paroxysmal/persistent AF type or de novo/redo procedure. Funding Acknowledgement Type of funding source: None

Esophageal temperature dynamics during high-power short-duration posterior wall ablation

Heart Rhythm ◽  
2020 ◽  
Vol 17 (5) ◽  
pp. 721-727 ◽  
Author(s):  
Chirag R. Barbhaiya ◽  
Edward V. Kogan ◽  
Lior Jankelson ◽  
Robert J. Knotts ◽  
Michael Spinelli ◽  
...  
Keyword(s):  
Short Duration ◽  
High Power ◽  
Posterior Wall ◽  
Esophageal Temperature ◽  
Temperature Dynamics

scholarly journals High-power short-duration radiofrequency ablation for atrial fibrillation

EP Europace ◽  
2021 ◽  
Vol 23 (Supplement_3) ◽  
Author(s):  
K Kassa ◽  
Z Nagy ◽  
B Kesoi ◽  
Z Som ◽  
C Foldesi ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Radiofrequency Ablation ◽  
Short Duration ◽  
Contact Force ◽  
High Power ◽  
Posterior Wall ◽  
Pericardial Tamponade ◽  
Fluoroscopy Time ◽  
Control Group

Abstract Funding Acknowledgements Type of funding sources: None. Introduction In recent times, high-power short-duration (HPSD) radiofrequency ablation (RFA) has emerged as an alternative strategy for pulmonary vein isolation (PVI) in atrial fibrillation (AF). Purpose We aimed to compare HPSD approach and conventional, ablation-index (AI) guided PVI using contact force sensing ablation catheters in respect of efficacy, safety, procedural characteristics, and outcome. Methods A total of 184 consecutive AF patients with first PVI were enrolled (age: 60 ± 11 years, paroxysmal: 56.5%, persistent: 43.5%) between November 2016 and December 2019. An ablation protocol of 50W energy with 15-20 g contact force was used for a duration of 8-12 sec based on the loss of capture concept in the HPSD group (n = 91) meanwhile, PVI was achieved according to the conventional power settings (posterior wall 25W, AI: 400, anterior wall 35W, AI: 550 ) in the control group (n = 93). During 1-year follow-up, documented AF for more than 30 seconds was considered as recurrence. Results Radiofrequency time and procedural time were significantly shorter using HPSD ablation (26.0 ± 12.7 min vs. 42.9 ± 12.6 min, p < 0.001, and 91 ± 30.1 min vs. 105.3 ± 28 min, p < 0.001). The HPSD strategy significantly lowered fluoroscopy time and radiation dose (5.47 ± 4.07 min vs. 8.15 ± 10.04 min, p = 0.019, and 430.2 ± 534.06 cGycm2 vs. 604.2 ± 633.9 cGycm2, p = 0.046). The HPSD group showed significantly less arrhythmia recurrence during 1-year follow-up with 76.9% of patients free from AF compared to 66.7% in the control group (p = 0.037). No pericardial tamponade, periprocedural thromboembolic complication, or atrio-oesophageal fistula occurred in the HPSD group. We observed 2 pericardial tamponade and 1 periprocedural stroke in the control group. Conclusions HPSD RFA for AF was demonstrated to be safe, and lead to significantly improved 1-year outcome in our mixed patient population. HPSD protocol significantly shortened procedural and radiofrequency time with decreased fluoroscopy time and radiation exposure.

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 >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.

scholarly journals The magnitude and the course of local impedance drop to guide successful AF ablation: insight from an Italian registry

EP Europace ◽  
2021 ◽  
Vol 23 (Supplement_3) ◽  
Author(s):  
V Schillaci ◽  
G Zucchelli ◽  
F Solimene ◽  
A De Simone ◽  
C Pandozi ◽  
...  
Keyword(s):  
Time Course ◽  
Rf Ablation ◽  
Af Ablation ◽  
Funding Sources ◽  
A Value ◽  
Successful Ablation ◽  
The Mean ◽  
Rf Applications ◽  
Af Recurrence

Abstract Funding Acknowledgements Type of funding sources: None. Background It has been demonstrated that an ablation strategy based on local impedance (LI) algorithm is helpful in guiding successful ablation of atrial fibrillation (AF) cases. How the magnitude and the course of LI drop could impact the effectiveness of ablation has to be proved. Purpose We aimed to evaluate LI drop characteristics in predicting effective radiofrequency (RF) ablation of consecutive AF cases. Methods Consecutive patients undergoing AF ablation at 8 Italian centers were included in the CHARISMA registry. A RF ablation catheter equipped with mini-electrodes technology and a dedicated algorithm was used to measure LI and to guide ablation. For our purpose, we defined the time to drop (τ) as the time for the first deflection of LI drop to the plateau. RF applications were targeted to a LI drop of 10 Ω and were stopped when a maximum cut-off LI drop of <40 Ω was observed. Successful single RF ablation was defined according with a reduction of signal voltage by at least 50% and inability to capture local tissue on pacing. The ablation endpoint was PVI as assessed by entrance and exit block. Follow-up were scheduled at 3, 6 and 12 months post-ablation. Results 153 consecutive patients (61% paroxysmal AF, 39% persistent AF) were enrolled in the study. 3556 point-by-point first-pass RF applications of >10 s duration were performed around PVs. The mean LI drop was 13 ± 8Ω, the mean τ was 18.7 ± 13s and the median LI drop/τ was 0.67 [QI-QIII, 0.37 – 1.17] Ω/s. Both absolute drops in LI and LI drop/τ were greater at successful ablation sites (n = 3122, 88%) than at ineffective ablation sites (n = 434, 12%) (14 ± 8Ω vs 6 ± 4Ω, p < 0.0001 for LI; 0.73[0.41–1.25]Ω/s vs 0.35[0.22–0.59]Ω/s for LI drop/τ, p < 0.0001). Every 5-point increment in LI drop was associated with successful ablation, with an OR of 3.13 (95%CI: 2.7 to 3.6, p < 0.0001), reaching the highest point when a value larger than 15 Ω was observed (99.9% of acute success). A significant trend was observed from lower to higher LI drop/τ values and a value greater than 0.65 Ω/s (best cut-off value on the basis of the ROC analysis) was significantly associated with successful RF delivery with an OR of 5.54 (95%CI: 4.31 to 7.11, p < 0.0001). No complications occurred during and after procedures. At 1-year follow-up, the AF recurrence rate was 12% after the 90-day blanking period. Conclusions The magnitude and time-course of the LI drop during RF delivery were associated with effective lesion formation. This ablation strategy for PVI guided by LI technology proved safe and effective, and resulted in a very low rate of AF recurrence over 1-year follow-up.

Sign in / Sign up

Export Citation Format

Share Document