High-power Short-duration Radiofrequency Research Articles

Peri-procedural anesthesia and patient pain experience in pulmonary vein isolation by means of very high-power short-duration radiofrequency ablation.

Very high-power short-duration (vHPSD) temperature-controlled radiofrequency ablation (vHPSD) may reduce ablation times and improve patient tolerability, permitting pulmonary vein (PV) isolation under mild conscious sedation. We evaluated of the anesthetic drugs use and patients' pain experience during vHPSD PV isolation. Fifty-eight patients, with paroxysmal and persistent atrial fibrillation (AF), treated with QDot Micro catheter and vHPSD (90 w for 4s) (vHPSD group), were compared with the last 33 patients treated with a surround flow contact force-sensing catheter guided by the ablation index (450 anteriorly at 50 W, 330 posteriorly at 40 W) (AI group). Anesthetic drugs use was compared as well as pain experience, measured using a 0-10 scale. All PVs were acutely isolated. Procedural time (78 ± 10min vs 84 ± 12min, p = 0.012), fluoroscopy time (369 ± 139s vs 441 ± 172s, p = 0.03), and RF time in the vHPSD group (8.3 ± 2.1min) were shorter than in the AI group (25 ± 11min, p < 0.001). Only 4 patients experienced an access site-related vascular complication (groin hematoma). Midazolam was required in 36 (62%) vHPSD group patients vs 31 (94%) AI group patients (p < 0.001). Fentanyl was required in 4 (7%) vHPSD group patients vs 25 (76%) AI group patients (p < 0.001). No patients required general anesthesia. Twenty-two (38%) vHPSD group patients underwent PV isolation without any anesthetic drug. Pain experience was significantly lower in vHPSD group (4.9 ± 2 vs 6.6 ± 1.8, p < 0.001). vHPSD radiofrequency ablation for PVI can be performed under conscious sedation using only benzodiazepine in most of patients without compromising patient pain experience.

Clinical efficiency and safety of high-power short-duration radiofrequency ablation in treatment of patients with atrial fibrillation

Clinical efficiency and safety of high-power short-duration radiofrequency ablation in treatment of patients with atrial fibrillation

Next-generation atrial fibrillation ablation: clinical performance of pulsed-field ablation and very high-power short-duration radiofrequency.

Pulsed-field energy (PFA) and very high-power short-duration radiofrequency (vHPSD-RF) are two novel ablation methods for pulmonary vein isolation (PVI). Both PFA and vHPSD-RF show promise for improving efficacy, safety, and reducing procedure durations. However, direct comparisons between these two techniques are scarce. Retrospective analysis of 82 patients with symptomatic AF. Of these, 52 patients received PFA and 30 received vHPSD-RF (90 W, 4s) as index procedure. At the 6-month follow-up, AF recurrence occurred in 4 patients following PFA and 5 patients following vHPSD-RF (p-value = 0.138). Significant improvements in the EHRA and NYHA stages were evident in both PFA (p < 0.001 and p = 0.047, respectively) and vHPSD-RF groups (p = 0.007 and p = 0.012, respectively). The total procedure duration and the left atrial dwell time were significantly shorter in the PFA group (64 ± 19min vs. 99 ± 32min, p < 0.001 and 41 ± 12min vs. 62 ± 29min, p < 0.001, respectively). The fluoroscopy time and dose area product were significantly higher in PFA (14 ± 6 vs. 9 ± 5min, p < 0.001 and 14 ± 9 vs. 11 ± 9Gy cm2, p = 0.046, respectively). One patient in the vHPSD-RF group suffered a stroke, not directly linked to the procedure (0 vs. 1 major complication, p = 0.366). Based on this retrospective single-center study, PFA and vHPSD-RF were associated with similar effectiveness and safety profiles. PFA was linked to shorter procedure times and higher radiation exposure compared to vHPSD-RF.

Pulmonary vein isolation using pulsed field ablation vs. high-power short-duration radiofrequency ablation in paroxysmal atrial fibrillation: efficacy, safety, and long-term follow-up (PRIORI study).

Pulsed field ablation (PFA) is a novel, non-thermal, cardiac tissue-selective ablation modality. To date, radiofrequency (RF)-guided high-power short-duration (HPSD) ablation represents the gold standard besides cryo-ablation for pulmonary vein isolation (PVI). This single-centre, retrospective study investigated the efficacy of PFA-PVI vs. HPSD-RF PVI in terms of single-procedure arrhythmia-free outcome and safety in a real-world setting. Consecutive, paroxysmal atrial fibrillation (AF) patients who underwent PVI using PFA or HPSD-RF were enrolled. In group PFA, PVI was performed using a pentaspline PFA catheter. The ablation procedure in group HPSD-RF was performed with RF energy (45 W, ablation index). A total of 410 patients (group PFA, 201; group HPSD-RF, 209) were included. There was no difference between both groups regarding age, gender, and CHA2DS2-VASc score. The procedure time was significantly shorter in group PFA [61 (44-103) vs. 125 (105-143) min; P < 0.001]; fluoroscopy time and dose area product were significantly higher in group PFA [16 (13-20) vs. 4 (2-5) min; P < 0.01 and 412 (270-739) vs. 129 (58-265) μGym2; P < 0.01]. The overall complication rates were 2.9% in group PFA and 6.2% in group HPSD (P = 0.158). There was one fatal stroke in the PFA group. The 1-year Kaplan-Meier estimated freedom from any atrial tachyarrhythmia was 85% with PFA and 79% with HPSD-RF (log-rank P = 0.160). In 56 repeat ablation procedures, the PV reconnection rate was 30% after PFA and 38% after HPSD-RF (P = 0.372). Both PFA and HPSD-RF were highly efficient and effective in achieving PVI in paroxysmal AF patients. The arrhythmia-free survival is comparable. The PV reconnection rate was not different.

Pulsed field vs very high-power short-duration radiofrequency ablation for atrial fibrillation: Results of a multicenter, real-world experience

BackgroundPulsed field ablation (PFA) and very high-power short-duration (vHPSD) radiofrequency ablation are the most recently introduced technologies for atrial fibrillation (AF) ablation. The procedural performance, safety, and effectiveness of PFA vs vHPSD are currently unknown. ObjectiveThe study aimed to compare PFA with vHPSD for the treatment of paroxysmal or persistent AF. MethodsWe conducted an observational, multicenter study enrolling 534 consecutive patients (63 ± 9 years; 36% female) with paroxysmal (n = 368 [69%]) or persistent (n = 166 [31%]) AF undergoing ablation by either PFA (Farapulse; n = 192) or vHPSD (90 W/4 seconds; QDOT Micro; n = 342) between 2020 and 2023. Atrial tachyarrhythmia recurrence after a 1-month blanking period was the primary efficacy end point and was assessed both overall and in propensity score–matched patients. The primary safety end point was a composite of procedure-related complications. ResultsSuccessful pulmonary vein isolation was achieved in all patients, with shorter procedure duration (PFA,70 minutes; vHPSD, 100 minutes; P < .001) but longer fluoroscopy time (PFA, 15 minutes; vHPSD, 7 minutes; P < .001) in the PFA group. PFA was associated with more frequent use of general anesthesia (P < .001). Primary safety outcome events occurred in 19 patients (3.5%), with similar prevalence in both groups (PFA, 4%; vHPSD, 3%; P = .745). After a median follow-up of 12 (9–12) months, survival free from recurrent atrial tachyarrhythmia was similar between the PFA and vHPSD groups, both overall (12-month estimate: PFA, 75%; vHPSD, 76%; log-rank P = .73) and in propensity score–matched patients (n = 342; 12-month estimate: PFA, 75%; vHPSD, 77%; log-rank P = .980). ConclusionIn a large, multicenter experience, PFA was associated with more common use of general anesthesia, shorter procedural times, and longer fluoroscopy exposure compared with vHPSD ablation, with both techniques displaying superimposable safety and efficacy.

Optimized workflow for pulmonary vein isolation using very high power short duration radiofrequency ablation

Abstract Background Point-by-point radiofrequency ablation is the most used invasive treatment of atrial fibrillation (AF). However, single-shot technologies are largely widespread due to their proved safety and efficacy. QDOT MICRO (QDM) is a novel contact force–sensing catheter optimized for temperature-controlled radiofrequency (RF) ablation that allows to maintain target temperature during 90 W ablations for ≤4 seconds. Purpose This study evaluates procedural safety and effectiveness as well as long-term effects of an optimized procedural workflow using QDM catheter to perform wide atrial circumferential ablation in patients with paroxysmal AF. Methods Consecutive patients referred for paroxysmal AF first ablation through pulmonary vein isolation (PVI) were prospectively enrolled. Every procedure was performed in general anesthesia by using CARTO3 Electroanatomical Mapping System BiosenseWebster QDM catheter and Deflectable Sheet VIZIGO as single sheet in left atrium. VHPSD was performed to encircling the posterior wall, while conventional-power temperature-controlled (CPTC) mode was used to encircling the anterior wall. The primary safety endpoint was incidence of primary adverse events within ≤7 days of ablation. The primary effectiveness endpoint was freedom from documented atrial tachyarrhythmia recurrence and acute procedural, repeat ablation, and antiarrhythmic drug failure. Results 120 enrolled participants (61 ± 12 years, 45% female) met eligibility criteria. Median procedural skin-to-skin time and RF application for ablating PVs were 56 and 17 minutes, respectively. Median ablation time was 22 minutes. First-pass isolation (entrance and exit block validation) was obtained in 98 % and inter-lesion distance was 4,8 ± 0,8 mm. In 100% of patients PVI was obtained without adverse events. The Kaplan-Meier estimated 12-month rate for clinical success (freedom from symptomatic recurrence of AF) was 93%, freedom from AF was 89% Conclusions PVI performed with point by point optimized workflow using VHPSD RF catheter in combination with steerable sheet is highly efficient and effective without compromising safety.

Pulsed field ablation versus very high power short duration radiofrequency ablation in atrial fibrillation: what is better?

Abstract Background The newly introduced non-thermal pulsed field ablation (PFA) is a promising technology for catheter ablation (CA) of atrial fibrillation (AF) with high acute success rates and good safety features. However studies have shown that very high power short duration (VHPSD) ablation is also highly effective and fast with potentially less arrhythmia recurrence compared to conventional radiofrequency ablation. Data comparing this two methods are lacking Objective The aim of this study is to compare two source of energy used for CA of AF in terms of procedural, clinical and outcome data Methods We conduced a retrospective observational study enrolling all patients (pts) from september 2021 to may 2023 who underwent CA of AF with PFA system and VHPSD. In the PFA group pulmonary veins isolation (PVI) was obtained using 2KV with eight application each vein, posterior wall isolation (PWI) of left atrium (LA) was obtained with application in the flower configuration of the catheter and then additional lesion were deployed at the operator’s discretion. In the VHPSD group the encircling of PV was obtained with 90W for 4 seconds radiofrequency pulses in posterior portions of the LA including LA PW, whereas 50W with ablation index target of 500 was used in the anterior portions of the PV and additional lesions. General anesthesia or deep sedation was carried out in all pts Results A total of 205 pts were included, n = 86 (42%) in the PFA group and N = 119 (58%) in the VHPSD group: paroxysmal (n = 62[72%], N = 64[54%]), persistent (n = 19[22%], N = 43[36%]), long standing persistent (n = 5[5%], N = 10[8%]). PVI was successful in all pts and additional lesions were delivered in n = 26 (30%) in PFA group and N = 76 (64%) in HVPSD group, mostly at the PW (n = 24[92%]; N = 50[66%]). The PFA group revealed a shorter procedura duration (80 ± 29 min vs 108 ± 39 min; p = 0,00001) but longer fluoroscopic time (21 ± 8 min vs 14 ± 10 min; p = 0,00001). The VHPSD group revealed more complications (N = 7[6%] vs n = 3[3%]) but without statistically significant difference (p = 0,43), the most frequent in the PFA group was vascular access complications instead in the VHPSD group was post-procedural pericarditis. Only one patient in VHPSD group had major complication with a post-procedural stroke but without residual neurological deficits. At follow-up after median of 14 (26-6) months, n = 61 pts in the PFA group (71%) and N = 91 in the VHPSD group (76%) were free from atrial arrhythmia (p = 0,79). In both group 7 pts recurrenced as atypical atrial flutter (n = 7[28%] PFA; N = 7[25%] VHPSD; p = 0,061) Conclusion PFA and VHPSD are effective and safe to CA of AF with comparable arrhythmia recurrenses. However procedure duration with PFA is significantly shorter and therefore may be of potential benefit in particular for elderly and frail pts. Further research, including randomized controlled trials, is needed to validate and compare these techniques more comprehensively

Posterior wall isolation in patients with persistent atrial fibrillation: a single center comparative study between ablation index and very high power short duration radiofrequency ablation protocol

Abstract Background Circumferential pulmonary veins ablation (CPVA) with posterior wall isolation (PWI) using radiofrequency catheter ablation (RFCA) is gaining increasing interest in terms of safety and efficacy. Purpose To compare procedural data and efficacy between two radiofrequency ablation protocols for the treatment of persistent atrial fibrillation (PersAF): very high power-short duration (vHPSD) ablation using a novel temperature-controlled ablation catheter and Ablation Index (AI) guided RFCA using traditional contact-force catheter. Methods This single center prospective study enrolled 75 consecutive patients (Group 1) with symptomatic PersAF undergoing RFCA using a novel contact-force catheter optimized for temperature-controlled ablation with microelectrodes and 6 thermocouples for real-time temperature monitoring during ablation. The vHPSD algorithm modulates power to maintain target temperature during these lesions (90 Watts, 4 s) in the posterior wall. RF delivery in anterior regions was performed in a temperature guided setting (1-45W, 45°C) to achieve a 500-550 AI. These patients were compared to 75 propensity matched patients (Group 2) undergoing PersAF ablation with traditional AI-guided ablation. Procedural data were compared between the two groups (Table 1). Procedural outcome was considered as loop recorder documented atrial arrhythmias recurrences and compared between the two groups. Results Seventy-five patients (69% male, 63.1±11.2 years old) underwent ablation with vHPSD protocol (Group 1). CPVA and PWI was achieved in all patients with total procedure and fluoroscopy times of 67.5±28.8 min and 4.5±2.8 min, respectively. After 12-month median follow-up, 57/75 patients (76%) were free from AF. Seventy-five propensity matched patients (69% male, 60.7±9.9 years old) have undergone ablation with standard contact-force catheter. CPVA and PWI was achieved in all patients with total procedure and fluoroscopy times of 81.99±20.5 min and 5.7±2.1 min, respectively. After 12-month median follow-up, 55/75 patients (73%) were free from AF. Procedural and fluoroscopy times were significantly lower in in Group 1 than in Group 2 (Table 1). AF recurrencies were comparable between the two groups as assessed with survival analysis (Figure 1, log-rank 0.509). There were no deaths or other severe periprocedural complications. Conclusions PWI on top of CPVA is effective in limiting arrhythmic recurrences following RFCA of PersAF. Compared to standard AI guided ablation, vHPSD protocol significantly reduces procedural time and fluoroscopy exposure. Clinical outcomes between the two protocols are similar.Figure 1

Pulsed field ablation versus very high-power short-duration radiofrequency ablation in persistent atrial fibrillation: a single-centre experience

Abstract Background Pulsed Field ablation (PFA) has recently emerged as a treatment strategy for patients with atrial fibrillation (AF) and early studies showed promising procedural data and durable pulmonary vein isolation (PVI). However, Very High-Power Short-Duration ablation (VHPSD) has previously reported good efficiency and mid-term outcomes, and only a few works compared these two procedures, especially in patients with persistent AF. Objective Our aim is to compare these different modalities of transcatheter ablation in patients with persistent AF, focusing mainly on some procedural aspects, safety and efficacy. Methods We performed a retrospective observational study enrolling all consecutive patients with persistent AF from September 2021 to May 2023 undergoing transcatheter ablation with PFA or VHPSD. In the first group, PVI was achieved by 2kV pulses with eight applications to each vein using both catheter configurations, while isolation of the posterior wall of the left atrium was achieved by applications through the only "flower" configuration; additional lesions were then added at the operator's discretion. In the second group, PVI was achieved by delivering 90W radiofrequency pulses for 4 seconds in the posterior portions of the left atrium and 50W pulses in the anterior region of the pulmonary veins; additional lesions were occasionally applied. All patients received general anaesthesia or deep sedation with fentanyl and dexmedetomidine. Results A total of 79 patients were included, n = 24 (30%) in the PFA group and N = 55 (70%) in the VHPSD one: early persistent AF (n= 2 [8,3%]; N = 7 [12,7%]), persistent AF (n= 17 [70,8%]; N = 36 [65,5%]), long-standing persistent AF (n= 5 [20,8%]; N = 12 [21,8%]). The two populations showed similar clinical features: CHA2DS2-VASc (median value 3 [0-6] in PFA vs 2 [0-6] in VHPSD, p = 0,10), indexed left atrial volume (mean value 42,6 ml/m² in PFA vs 42,4 ml/m² in VHPSD, p = 0,07) and EF (mean value 55,4% in PFA vs 54,8% in VHPSD, p = 0,33). PVI was successfully achieved in all patients. Nevertheless, the PFA group was associated with shorter procedural duration (92,1 ± 36,9 vs 134,2 ± 36,1 minutes, p = 0,00001) but longer fluoroscopy time (25,5 ± 9,3 vs 17,4 ± 11,5 minutes, p = 0,001); it also showed a lower rate of minor complications (n = 1 [4,2%] vs N = 3 [5,5%], p = 0,057), even though serious complications were not observed in either group. After a median follow-up of 14 (9-26) months, n = 19 [79.2%] in the PFA and N = 43 [78.2%] in the VHPSD population were free of any atrial arrhythmia (p = 0,92). Conclusion PFA allows faster procedures, representing a major advantage for the operator and the patient, who is at lower risk of peri-procedural complications. On the other hand, VHPSD correlates with shorter fluoroscopy times, reducing exposure to ionizing radiation. Finally, the two procedures show similar mid-term efficacy in terms of recurrence-free time.

Relative contribution of contact force to lesion depth using high-power short-duration radiofrequency applications

Relative contribution of contact force to lesion depth using high-power short-duration radiofrequency applications

Using computed tomogram atrial myocardial thickness maps in high-power short-duration radiofrequency pulmonary vein isolation: UTMOST AF.

High-power short-duration (HPSD) ablation creates wide, shallow lesions using radiofrequency (RF) heating. It is uncertain if adjusting RF energy based on atrial wall thickness provides extra benefits. We studied the safety and effectiveness of tailored HPSD energy based on left atrial (LA) wall thickness (LAWT) for circumferential pulmonary vein isolation (CPVI) in patients with paroxysmal atrial fibrillation (PAF). We enrolled 212 patients (68.4% male, mean age: 59.5 ± 11.0 years) and randomly assigned them to two groups: LAWT-guided CPVI (WT, n = 108) and conventional CPVI (control, n = 104). Both groups used an open irrigated-tip deflectable catheter to apply 50 W for 10 s to the posterior LA, while controls used 60 W for 15 s on other LA regions. RF delivery time in WT was titrated (15 s at LAWT > 2.1 mm, 13 s at 1.4-2.1 mm, and 11 s at <1.4 mm) according to the computed tomogram-myocardial thickness color map. After a mean follow-up of 13.4 ± 7.0 months, the WT and control groups showed no significant difference regarding clinical recurrence rate (13.9% vs. 5.8%, respectively; p = .061) and major complication rate (4.6% vs. 3.8%, respectively; p > .999). The total procedure time, cardioversion rate, and post-procedural AAD prescription rates did not significantly differ between the groups. The LAWT-guided energy titration strategy did not result in improved procedural safety and efficacy compared to the conventional 50-60 W-HPSD CPVI in patients with PAF.

Biophysical Behavior of Very High-Power Short-Duration Radiofrequency Ablation in Pulmonary Vein Isolation: Fast but Gently—Implications for a Successful Procedure

The very high-power short-duration (vHP-SD) ablation strategy is an alternative for pulmonary vein isolation (PVI) in patients with paroxysmal atrial fibrillation (PAF). However, the acute procedural biophysical behavior of successful lesion creation by means of this technique is still unexplored. We performed a retrospective case–control study aimed at evaluating the behavior of vHP-SD ablation parameters with the QDOT MICRO™ ablation catheter (Biosense Webster) compared with standard radiofrequency (RF) ablation with the THERMOCOOL SMARTTOUCH® ablation catheter. Twenty consecutive cases of symptomatic PAF treated with the QDOT MICRO™ ablation catheter from December 2022 to March 2023 were compared with cases treated with the standard technique. The acute procedural success of PVI was obtained in all cases with 2192 RF applications, and no adverse events occurred. Compared with the controls, vHP-SD cases featured a significant reduction in procedural time (47 ± 10 vs. 56 ± 12 min, p = 0.023), total RF time (3.8 [CI 3.4–4.6] vs. 21.2 [CI 18.4–24.9] min, p &lt; 0.001), ablation phase time (25 ± 5 vs. 39 ± 9 min, p &lt; 0.001), and irrigation volume (165 [CI 139–185] vs. 404 [CI 336–472] ml, p &lt; 0.001). In vHP-SD RF ablation, a contact force of 5 g minimum throughout the 4 s of RF application appeared to be statistically significant in terms of an impedance drop of at least 10 Ohm (OR 2.63 [CI 1.37; 5.07], p = 0.003). In contrast, in the control group, the impedance drop depended linearly on the contact force. This suggests a different biophysical behavior of vHP-SD ablation. A maximum temperature and minimum contact force of &gt;5 g independently predicted an effective impedance drop in vHP-SD. Increasing the contact force over 5 g during 4 s of vHP RF application might not be necessary to achieve a successful lesion.

Atrial fibrillation catheter ablation: electroporation against high-power short duration radiofrequency

Abstract Background Pulmonary vein isolation (PVI) is one of the cornerstones of rhythm-control therapy for symptomatic atrial fibrillation (AF) patients. The new ablation technologies of pulse field ablation (PFA) and high-power short-duration radiofrequency ablation (HPSD) with the new QDOT® catheter have been recently introduced in the EP lab. Aims To evaluate and compare the efficacy, and safety of single-shot PFA and HPSDRA for PVI in AF symptomatic patients. Methods Single centre, retrospective study of consecutive patients undergoing PVI with PFA or HPSD between May-December 2022. Data on demographic, procedural and clinical/ electrocardiographic recurrence (assessed after a 3-months blanking period) were analysed. Comparative analysis between both techniques was performed. Results One hundred and ten consecutive patients were included (63 ± 11 years, 75% men), with a mean CHA2DS2-VASc score of 2±1 points, median LVEF of 61% [IQR 57-62%] and a median left atrial volume index (by CT scan) of 56 mL/m2 [IQR 51-67 mL/m2]. 55% patients presented paroxysmal-AF and 19 patients (17%) performed a redo ablation. 47% (n=52) patients performed HPSD and 53% (n=58) PFA (all with CARTO®3D system v.7 and high-density mapping). In the HPSD: median RF ablation time was 792 sec [IQR 614-919sec], while in PFA was 90 sec [IQR 30-138 sec]. Median time of catheter inside the LA for PFA was 18 min [IQR 2-33 min]. Comparing HPSD and PFA (Fig 1): median procedure time was similar (91 min [IQR 71-107 min] vs 89 min [IQR 66-111 min], p=0.261), while median fluoroscopy time was lower with HPSD (5.4 min [IQR 3.1-6.8 min] vs 13.2 min [IQR 10.3-15.6 min], p&amp;lt;0.001); posterior wall isolation (PWI) was performed in 5 (10%) HPSD vs 21 (37%) PFA patients (p&amp;lt;0.001). All PFA patients undergoing PWI had first pass isolation, while only 40% of HPSD had first pass isolation. When performed PVI only, PFA presents a lower median procedure time than HPSD (76 min [IQR 62-93 min] vs 97 min [IQR 69-135 min], p=0.048). There was only one major complication, a cardiac tamponade with PFA, treated with pericardiocentesis. At 3 months of follow-up, 17% (n=10) patients had clinical or electrocardiographic AF recurrence: 7 PFA patients and 3 HPSD patients (p=0.127). Conclusions PFA and HPSD were both feasible and safe. When undergoing PVI-only, procedure time was lower with PFA. In patients undergoing PWI, PFA achieved higher first pass isolation. Although still in its early real-world evaluation, both techniques seem to be efficient, providing low AF recurrence during follow-up.

Revisiting pulmonary vein stenosis after high-power short-duration radiofrequency ablation in patients with atrial fibrillation

Abstract Background High-power short-duration atrial fibrillation catheter ablation (HPSD-AFCA) of pulmonary vein (PV) isolation reduces the procedure time without a difference in the efficacy as compared to conventional power AFCA (ConvP-AFCA). PV stenosis (PVS) after AFCA is a rare complication. Purpose We compared the frequency of symptomatic PVS as a long-term complication between the ConvP-AFCA and HPSD-AFCA groups. Methods We included 3,851 patients undergoing AFCA between 2009 and 2022 prospectively. We evaluated the characteristics of patients diagnosed with clinically symptomatic PVS, ascertained using computed tomography during the follow-up period. The risk of PVS was compared between the ConvP-AFCA and HPSD-AFCA groups using propensity overlap weighting. Results Symptomatic PVS was diagnosed in 14 (0.4%) patients at a mean of 342.9 days after the procedure. After overlap weighting, PVS was significantly more frequent in the HPSD-AFCA group (incidence: HPSD-AFCA, 0.8% vs. ConvP-AFCA, 0.2%; weighted hazard ratio [HR] 6.27, 95% confidence interval [CI] 2.15-18.28; P&amp;lt;0.001). In the multivariable Cox regression analyses, repeat AFCA procedures (HR 3.52, 95% CI 1.18-10.55; P=0.024) and paroxysmal AF (HR 8.29, 95% CI 1.08-63.82; P=0.042) were also independently associated with PVS after AFCA. Among the PVs of patients with PVS, stenotic PVs had shorter antral diameters and a smaller cross-sectional area than non-stenotic PVs on preprocedural computed tomographic evaluations. Conclusion HPSD-AFCA, compared to ConvP-AFCA, was associated with a 6-fold increased risk of symptomatic PVS. Caution is required, especially in patients with plans for a repeated AFCA, paroxysmal AF, or small PV antrum.

Revisiting symptomatic pulmonary vein stenosis after high-power short-duration radiofrequency ablation in patients with atrial fibrillation.

Revisiting symptomatic pulmonary vein stenosis after high-power short-duration radiofrequency ablation in patients with atrial fibrillation.

Evaluation of lesion characteristics and baseline impedance on high-power short-duration radiofrequency catheter ablation using computer simulation.

Myocardium baseline impedance (BI) is an important factor in ablation effectiveness. This study examined the performance of low-power and long-duration (LPLD), high-power and short-duration (HPSD) ablation at different BIs by computer simulation. A 3D model of the ablation region was constructed for simulation, and in vitro experiments were performed to validate the simulation. Three ablation power and duration configurations of 30W/30s, 50W/10s, and 90W/5s were used for simulation with BI values of 90, 100, 110, 120, 130, and 140Ω. Roll-off time and ablation volume were measured to evaluate ablation results. The simulation is consistent with the in vitro experiments. When BI is changed from 90 [Formula: see text] to 140 [Formula: see text], the lesion volume over 50°C with BI of 140[Formula: see text] was reduced by 6.3%, 6.7%, and 7.3% for 30W/30s, 50W/10s, and 90W/5s configurations, respectively, and the lesion volume over 100°C was reduced by 62.8%, 49.7%, and 22.5% under 30W/30s, 50W/10s, and 90W/5s, respectively. Simulation results revealed that HPSD (vHPSD) and LPLD ablation were more affected by changes in BI in the lesion volumes over 50°C and 100°C, respectively, and demonstrated that resistive and conductive heating were the main heating effects in HPSD (vHPSD) and LPLD, respectively.

Impact of a standardized pacing protocol on end point verification and first pass isolation using a multipolar pulsed-field ablation catheter for pulmonary vein isolation

Pulsed-field ablation (PFA) has emerged as a novel treatment strategy for patients with atrial fibrillation (AF) ( 1 Badertscher P, Weidlich S, Serban T, et al. Pulsed-field ablation versus single catheter high-power short-duration radiofrequency ablation for atrial fibrillation: procedural characteristics, myocardial injury and midterm outcomes. Heart Rhythm 2023. Google Scholar , 2 Reddy VY, Dukkipati SR, Neuzil P, al. Pulsed Field Ablation of Paroxysmal Atrial Fibrillation: 1-Year Outcomes of IMPULSE, PEFCAT, and PEFCAT II. JACC Clin Electrophysiol 2021; 7(5):614–627. Google Scholar ). In general, acute pulmonary vein isolation (PVI) may be confirmed by entrance and exit block ( 3 Duytschaever M. Meyer G de Acena M. et al. Lessons from dissociated pulmonary vein potentials: entry block implies exit block. Europace. 2013; 15: 805-812 Crossref PubMed Scopus (25) Google Scholar ). The penta-spline PFA catheter only provides larger electrodes and wider inter-electrode distance making such an assessment less reliable. Little is known about the required number of applications when using PFA as systematically assessed via exit block testing. Likewise, since close proximity of the PFA catheter to the PV ostium seems to be of importance ( 2 Reddy VY, Dukkipati SR, Neuzil P, al. Pulsed Field Ablation of Paroxysmal Atrial Fibrillation: 1-Year Outcomes of IMPULSE, PEFCAT, and PEFCAT II. JACC Clin Electrophysiol 2021; 7(5):614–627. Google Scholar ), catheter positioning might be optimized by pacing before the first PFA application and adjusting contact depending on the ability to capture atrial myocardium. Thus, our aim was to assess the number of PFA applications per PV until acute PVI was observed and to assess the impact of a standardized pacing protocol on first pass isolation (FPI) confirmed via electroanatomical mapping (EAM). We prospectively enrolled consecutive patients undergoing their first PVI. In brief, the PFA 31 mm Farawave© catheter (Boston Scientific, Marlborough, MA) was inserted into the left atrium via a single transseptal puncture. PVI was performed as described previously ( 2 Reddy VY, Dukkipati SR, Neuzil P, al. Pulsed Field Ablation of Paroxysmal Atrial Fibrillation: 1-Year Outcomes of IMPULSE, PEFCAT, and PEFCAT II. JACC Clin Electrophysiol 2021; 7(5):614–627. Google Scholar ). In group 1 no standardized pacing protocol was applied prior or after PVI. In group 2, pacing was performed prior to the first application across all five bipoles to assess proximity of the PFA catheter to the PV ostium. Entrance and exit block were then assessed after each PFA application per PV separately. PVI was subsequently confirmed via EAM. The study was approved by the local ethics committees and adhered to the Helsinki Declaration.

Peri-procedural anesthesia and patient pain experience in pulmonary vein isolation by means of very high power short duration radiofrequency ablation

Abstract Funding Acknowledgements Type of funding sources: None. Background Very high-power short-duration (vHPSD) temperature-controlled radiofrequency ablation (vHPSD) may reduce ablation times and improve patient tolerability, permitting pulmonary vein (PV) isolation under mild conscious sedation. Purpose Evaluate the anesthetic drugs use and patients ‘pain experience during vHPSD PV isolation. Methods Thirty-three consecutive patients, with paroxysmal atrial fibrillation (AF), treated with QDot Micro catheter and vHPSD (90 w for 4 s) (vHPSD Group), were compared with the last 33 consecutive patients, with paroxysmal AF, treated with a surround flow contact force-sensing catheter guided by the ablation index (450 at anterior and superior sites at 50 W, 330 at posterior and inferior sites at 40 W) (AI Group). Anesthetic drugs (midazolam and fentanyl) use were compared as well as pain experience, measured using a 0-10 scale. Results All PVs were isolated. PV isolation ablation time in the vHPSD Group (5.9±1.4 min) was shorter than in the AI Group (25±11 min, p&amp;lt;0.001). Pain experience was significantly lower in vHPSD group (4.5±2 vs 6.6±1.8, p&amp;lt; 0.001). No patients required general anesthesia; fentanyl use was required in 4 vHPSD Group patients vs 25 AI Group patients (p&amp;lt;0.001). A lower dose of midazolam was required in vHPSD Group (2.3±1.2 mg vs 3.6±1.7 mg, p &amp;lt; 0.001). Conclusions vHPSD radiofrequency ablation for PVI can be performed under conscious sedation using only benzodiazepine in most of patients without compromising patient pain experience.

Pulsed-field ablation versus single catheter high-power short-duration radiofrequency ablation for atrial fibrillation: procedural characteristics, myocardial injury and midterm outcomes

Abstract Funding Acknowledgements Type of funding sources: None. Background Pulsed-field ablation (PFA) has emerged as a novel treatment strategy for patients with atrial fibrillation (AF). A direct comparison to high-power short-duration (HPSD) radiofrequency (RF) ablation using a single catheter is lacking. Aim To compare pulmonary vein isolation (PVI) using PFA versus single catheter HPSD-RF ablation regarding efficiency, safety, myocardial injury, and outcomes. Methods 119 patients underwent PVI and were included (age 65.6 ± 10 years, ejection fraction 0.55 ± 0.11, left atrial size 41 ± 6.6 mm, paroxysmal AF 55%). 56 patients (47%) underwent PFA using a multi-electrode pentaspline PFA catheter with a biphasic waveform and 63 patients (53%) underwent single catheter HPSD-RF ablation without a multipolar mapping catheter. Results Using PFA the median procedure time was significantly shorter compared to the single catheter HPSD-RF group with 58 (IQR 51-70) min versus 83 (IQR 71-99) min (p&amp;lt;0.001), while fluoroscopic time was significantly longer with 12 (IQR 10-16) min versus 2.2 (IQR 1.3-3.6) min (p&amp;lt;0.001). First-pass isolation was achieved in 91% of the PFA group and 88% in the HPSD-RF group. 3.3 catheters vs. 1.0 catheters were used in the PFA group versus the HPSD-RF group, p&amp;lt;0.01. One procedural complications was observed in the PFA group and one complication in the HPSD-RF group (Tamponades). High sensitivity cardiac troponin levels were on average significantly higher in patients using the PFA system, 1520 (IQR 1010-1980) ng/l compared to 897 (IQR 725-1240) ng/l in the HPSD-RF group. During a median follow-up of 177 days (IQR 92-300), AF recurrence was observed in five patients (9%) from the PFA group and in 15 patients (24%) from the HPSD-RF group. (Figure 1) Conclusion PFA showed shorter procedure times but longer fluoroscopy times, higher levels of hs cTnT, and a possible improved AF-free survival.

Using computed tomogram atrial myocardial thickness maps in high-power short-duration radiofrequency pulmonary vein isolation: a prospective randomized clinical study

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): This work was supported by a grant [HI21C0011] from the Ministry of Health and Welfare, a grant [NRF-2020R1A2B5B01001695] from the Basic Science Research Program run by the National Research Foundation of Korea (NRF) which is funded by the Ministry of Science, ICT &amp; Future Planning (MSIP), and a grant [RS-2022-00141473] from Cross-ministerial tasks. Background High-power short-duration (HPSD) ablation generates wide and contiguous but shallow lesions by radiofrequency (RF) resistive heating. It is unknown whether RF energy titration has additional benefits depending on the atrial wall thickness. Purpose We aimed to compare the efficacy and safety of HPSD energy titration depending on left atrial wall thickness (LAWT) during circumferential pulmonary vein isolation (CPVI) in patients with paroxysmal atrial fibrillation (PAF). Methods We prospectively randomized 224 patients with PAF (69.2% males, 59.3±12.0-years-old) into either the LAWT-guided CPVI group (WT, n=113) or the conventional CPVI group (Control, n=111). We delivered 15s of constant RF (contiguous lesion 2mm dots, FlexAbility) at 60W in the Control group but titrated the RF duration in the WT group (15 s at LAWT&amp;gt;2.1mm, 13s at 1.4–2.1mm, and 11s at &amp;lt;1.4mm) referencing the computed tomogram-myocardial thickness color map. The primary endpoints were safety and AF recurrence after a single procedure; the secondary endpoints were the procedure time, cardioversion rate, and response to anti-arrhythmic drugs (AADs). Results After a mean follow-up of 13.4±7.0 months, the clinical recurrence rate (13.3% vs. 8.1%, log-rank p=0.302) and the complication rate (8.0% vs. 4.5%, p=0.427) did not differ between the two groups. The total procedure time (p=0.391) and cardioversion rate (p=1.000) did not significantly differ between the two groups. During the final follow-up, sinus rhythm was maintained without AADs in 72.6% of the WT group and 80.2% of the Control group (p=0.237). Conclusions LAWT-guided energy titration resulted in efficacy and safety equivalent to that of constant 15s 60W-HPSD CPVI in patients with PAF.