Repeat pulmonary vein isolation and anterior line ablation using a novel point-by-point pulsed-field ablation system.

BACKGROUND: Pulsed-field ablation (PFA) is a nonthermal energy source for ablation of cardiac arrhythmias. This study investigated the prospective outcomes of a novel PFA generator in conjunction with a commercially available, contact force-sensing, focal ablation catheter. OBJECTIVE: The purpose of this study was to assess the feasibility, safety, and lesion characteristics of point-by-point PFA in consecutive patients undergoing repeat ablation of atrial fibrillation (AF). METHODS: The study involved reisolation of pulmonary veins (PVs) with electrical reconnection and the creation of an anterior line (AL) in patients with anterior substrate or durable pulmonary vein isolation (PVI). RESULTS: In 24 patients (46% female; mean age 67 ± 10 years; 67% persistent AF), successful reisolation of 27 of 27 reconnected PVs (100%) was performed. In 19 patients, AL ablation was performed, with bidirectional block in 16 (84%), median ablation time 26 [21, 33] minutes, and first-pass bidirectional block in 13 patients (68%). Acute AL reconduction occurred in 8 of 19 patients (42%). Among these 8 patients, a subsequent sustained block of the AL was achieved in 5 (63%). Ultra-high-density electroanatomic mapping revealed homogeneous but relatively large low-voltage areas in the ablated regions. Median procedural, left atrial dwell, and fluoroscopy times were 100 [90, 109] minutes, 83 [75, 98] minutes, and 10 [8, 13] minutes, respectively. No major or minor complications occurred. CONCLUSION: This study demonstrated feasibility, acute efficacy, and safety of point-by-point PFA for repeat PVI and AL ablation. Further studies are warranted to assess the long-term durability and comparison with established ablation methods.

The infrastructure of electrophysiology centers impacts the management of cardiac tamponade-Results from a national survey.

BACKGROUND: Although electrophysiological (EP) centers have institutional standards, evidence on management of cardiac tamponade is lacking. AIM AND METHODS: A physician-based survey was conducted by sending out questionnaires to all hospitals in Germany performing EP procedures. To evaluate the infrastructure of EP centers and the impact of center volume and onsite cardiac surgery on the management of cardiac tamponade, the results of the survey were analyzed for low-volume (0-250 procedures per year), mid-volume (250-500 procedures), and high-volume (>500 procedures) centers, as well as for centers with and without onsite cardiac surgery. RESULTS: A total of 341 centers were identified and 189/341 (55%) returned data sets were analyzed. Most types of EP procedures are performed across all kinds of centers. Ablation of ventricular tachycardia (VT) is concentrated in higher volume centers and in centers with onsite cardiac surgery. None of the participating low-volume centers and only 13% of centers without onsite cardiac surgery responded to performing epicardial VT ablation. Irrespective of center volume and onsite cardiac surgery, neither body mass index nor age was reported to be an exclusion criterion for ablation procedures. Higher volume centers and centers with onsite cardiac surgery more often have dedicated EP laboratories and EP-nursing teams. Also, differences regarding periprocedural safety precautions and management of cardiac tamponade were found for low-, mid-, and high-volume centers, as well as for centers with and without onsite cardiac surgery. CONCLUSION: While center volume and onsite cardiac surgery do not impact patient selection, there are differences in ablation spectrum, infrastructure, periprocedural safety precautions, and treatment of tamponade.

Acute lesion extension following pulmonary vein isolation with two novel single shot devices: Pulsed field ablation versus multielectrode radiofrequency balloon.

INTRODUCTION: Pulsed-field ablation (PFA) and the multielectrode radiofrequency balloon (RFB) are two novel ablation technologies to perform pulmonary vein isolation (PVI). It is currently unknown whether these technologies differ in lesion formation and lesion extent. We compared the acute lesion extent after PVI induced by PFA and RFB by measuring low-voltage area in high-density maps and the release of biomolecules reflecting cardiac injury. METHODS: PVI was performed with a pentaspline catheter (FARAPULSE) applying PFA or with the compliant multielectrode RFB (HELIOSTAR). Before and after PVI high-density mapping with CARTO 3 was performed. In addition, blood samples were taken before transseptal puncture and after post-PVI remapping and serum concentrations of high-sensitive Troponin I were quantified by immunoassay. RESULTS: Sixty patients undergoing PVI by PFA (n = 28, age 69 ± 12 year, 60% males, 39.3% persistent atrial fibrillation [AF]) or RFB (n = 32, age 65 ± 13 year, 53% males, 21.9% persistent AF) were evaluated. Acute PVI was achieved in all patients in both groups. Mean number of PFA pulses was 34.2 ± 4.5 and mean number RFB applications was 8.5 ± 3 per patient. Total posterior ablation area was significantly larger in PFA (20.7 ± 7.7 cm²) than in RFB (7.1 ± 2.09 cm²; p < .001). Accordingly, posterior ablation area for each PV resulted in larger lesions after PFA versus RFB (LSPV 5.2 ± 2.7 vs. 1.9 ± 0.8 cm², LIPV 5.5 ± 2.3 vs. 1.9 ± 0.8 cm², RSPV 4.7 ± 1.9 vs. 1.6 ± 0.5 cm², RIPV 5.3 ± 2.1 vs. 1.6 ± 0.7 cm,² respectively; p < .001). In a subset of 38 patients, increase of hsTropI was higher after PFA (625 ± 138 pg/mL, n = 28) versus RFB (148 ± 36 pg/mL, n = 10; p = .049) supporting the evidence of larger lesion extent by PFA. CONCLUSION: PFA delivers larger acute lesion areas and higher troponin release upon successful PVI than multielectrode RFB-based PVI in this single-center series.

Novel Radiofrequency Balloon Catheter　- Impact of Ablation Parameters on Single-Shot Isolation.

BACKGROUND: A novel multielectrode radiofrequency balloon (RFB) catheter has been released for pulmonary vein isolation (PVI).Methods and Results: In this observational study consecutive patients with drug-refractory paroxysmal or persistent atrial fibrillation (AF) undergoing first-time PVI were enrolled in 2 high-volume ablation centers. All procedures were conducted in conjunction with a 3D-mapping system. Clinical, procedural and ablation parameters were systematically analyzed. 105 patients (58% male; 52% paroxysmal AF, 68±11.3 years mean age, left atrial volume index 38.6±14.8 mL/m2) were included. 241/412 (58.5%) PVs were successfully isolated with a single shot (SS), with a time-to-isolation of 11.6±8 s. Total number of radiofrequency applications was 892 (mean 2.2/PV), resulting in successful isolation of 408/412 (99%) PVs at the end of the procedure. Mean electrodes' impedance drop was significantly higher in the SS-PVI compared with non-SS applications (21.5±6.6 vs. 18.6±6.5 Ohm). Concordantly, higher temperature rise was observed in the SS vs. non-SS applications (10.9±4.9℃ vs. 9.6±4.7℃). CONCLUSIONS: In this multicenter real-world study, mean impedance drop and temperature rise were associated with successful SS-PVI applying the novel RFB catheter. These parameters may help to guide efficient usage of the new RF balloon.

Association of genetic risk and outcomes in patients with atrial fibrillation: interactions with early rhythm control in the EAST-AFNET4 trial.

AIMS: The randomized Early Treatment of Atrial Fibrillation for Stroke Prevention Trial found that early rhythm control reduces cardiovascular events in patients with recently diagnosed atrial fibrillation (AF) compared with usual care. How genetic predisposition to AF and stroke interacts with early rhythm-control therapy is not known. METHODS AND RESULTS: Array genotyping and imputation for common genetic variants were performed. Polygenic risk scores (PRS) were calculated for AF (PRS-AF) and ischaemic stroke risk (PRS-stroke). The effects of PRS-AF and PRS-stroke on the primary outcome (composite of cardiovascular death, stroke, and hospitalization for acute coronary syndrome or worsening heart failure), its components, and recurrent AF were determined.A total of 1567 of the 2789 trial patients were analysed [793 randomized to early rhythm control; 774 to usual care, median age 71 years (65-75), 704 (44%) women]. Baseline characteristics were similar between randomized groups. Early rhythm control reduced the primary outcome compared with usual care [HR 0.67, 95% CI: (0.53, 0.84), P < 0.001]. The randomized intervention, early rhythm control, did not interact with PRS-AF (interaction P = 0.806) or PRS-stroke (interaction P = 0.765). PRS-AF was associated with recurrent AF [HR 1.08 (01.0, 1.16), P = 0.047]. PRS-stroke showed an association with the primary outcome [HR 1.13 (1.0, 1.27), P = 0.048], driven by more heart failure events [HR 1.23 (1.05-1.43), P = 0.010] without differences in stroke [HR 1.0 (0.75, 1.34), P = 0.973] in this well-anticoagulated cohort. In a replication analysis, PRS-stroke was associated with incident AF [HR 1.16 (1.14, 1.67), P < 0.001] and with incident heart failure in the UK Biobank [HR 1.08 (1.06, 1.10), P < 0.001]. The association with heart failure was weakened when excluding AF patients [HR 1.03 (1.01, 1.05), P = 0.001]. CONCLUSIONS: Early rhythm control is effective across the spectrum of genetic AF and stroke risk. The association between genetic stroke risk and heart failure calls for research to understand the interactions between polygenic risk and treatment. REGISTRATION: ISRCTN04708680, NCT01288352, EudraCT2010-021258-20, www.easttrial.org.

Efficacy and safety in patients treated with a novel radiofrequency balloon: a two centres experience from the AURORA collaboration.

AIMS: A novel irrigated radiofrequency (RF) balloon (RFB) for pulmonary vein (PV) isolation (PVI) was released in selected centres. We pooled the procedural data on efficacy and safety of RFB-PVI from two high volume German centres. METHODS AND RESULTS: Consecutive patients with RFB procedures were enrolled. A 3D electroanatomical left atrial map guided the RFB navigation. Every RF delivery lasted 60 s, and duration was automatically reduced to 20 s for electrodes facing the posterior wall. Procedural data and post-procedural endoscopy data (<48 h) were analysed. Data from 140 patients were collected (57% male, 67 ± 11 years, 57% paroxysmal atrial fibrillation). There were 547 PVs identified, and 99.1% could be isolated using solely the RFB. Single-shot PVI was recorded in 330/547 (60%) PVs. Median time to isolation during the first application was 10 s (IQR 8-13). A total of 2.1 ± 1.8 applications per PV were delivered, with the left superior PV requiring more application compared to other PVs. Median procedure and fluoroscopy time were 77 min (61-99) and 13 min (10-17), respectively. Major safety events were recorded only in the first 25 cases at each centre and included 1/140(0.7%) cardiac tamponade, 1/140(0.7%) phrenic nerve palsy, and 2/140 strokes (1.4%). An oesophageal temperature rise was recorded in 81/547 (15%) PVs, and endoscopy detected oesophageal lesions in 7/85 (8%) patients undergoing endoscopy. CONCLUSION: The RFB showed a high efficacy allowing for fast PVI procedures, and 60% of PVs could be isolated at the first application. Most safety events were recorded during the learning phase. An oesophageal temperature monitoring is suggested: oesophageal lesions were detected in 8% of patients.

A novel saline-based occlusion tool allows for dye-less cryoballoon-based pulmonary vein isolation and fluoroscopy reduction.

Background: Cryoballoon (CB)- based pulmonary vein isolation (PVI) remains guided by fluoroscopy and dye. The novel saline injection-based occlusion tool allows for pulmonary vein (PV)-occlusion assessment without the need for dye injection. Aim: To compare KODEX-EPD guided CB-PVI using the novel saline injection-based workflow with conventional cryoablation for acute efficacy, fluoroscopy exposure and dye volume. Methods: Consecutive atrial fibrillation (AF)- patients undergoing CB-PVI in conjunction with KODEX-EPD (CryoEPD group) were analyzed. Patients undergoing conventional CB-PVI (Cryo group) in the same time period acted as controls. Results: One hundred forty patients [91/140 (65%) persistent AF] were studied. Seventy patients underwent CryoEPD procedures [64 ± 13 years, 21 (30%) female] and seventy patients underwent Cryo procedures [68 ± 10 years, 27 (39%) female].A total of 560 PVs were identified and successfully isolated. Mean procedure time was 66 ± 15 min for the CryoEPD group, and 65 ± 19 min for the Cryo group (p = 0.3). Fluoroscopy time (CryoEPD 6 ± 4 min; Cryo 13 ± 6 min, p < 0.001) and dose area product (CryoEPD 193 [111; 297] cGycm2; Cryo 381 [268; 614] cGycm2, p < 0.001) were lower in patients undergoing CryoEPD compared with Cryo procedures. No dye was needed in the CryoEPD group while 53 ± 18 ml dye per patient were administered for the Cryo group (p < 0.001). The overall complication rate was comparable between both groups (p = 0.5). Conclusion: KODEX-EPD guided AF-ablation enables dye-free CB-based PVI with reduced fluoroscopy exposure when compared to conventional CB-ablation, without differences in acute procedural outcomes or procedure duration.

Perioperative Arrhythmias.

BACKGROUND: Perioperative arrhythmias are common depending on the type of the operation and can increase morbidity and mortality. METHODS: This review is based on pertinent publications retrieved by a selective search in PubMed, as well as the relevant European guidelines. RESULTS: Arrhythmias are seen in more than 90% of cardiac operations; they are usually transient and often asymptomatic. The risk factors for arrhythmia include ion channel diseases, old age, structural heart disease, cardiac surgery, noncardiac surgery with major fluid shifts, and pulmonary resection. The full spectrum of supraventricular and ventricular arrhythmias can arise perioperatively. Correct ECG interpretation, consideration of the arrhythmia in the overall clinical context, and an understanding of its causes, pathophysiology, and options for effective treatment are critically important. According to a meta-analysis, betablockers lower the risk of perioperative atrial fibrillation (OR = 0.56; 95% confidence interval: [0.35; 0.91]). If anticoagulant treatment is not interrupted for surgery, there is less bleeding with direct oral anticoagulants than with vitamin K antagonists (relative risk: 0.62 [0.47; 0.82]). Moreover, clinical follow-up is important, especially for patients with new-onset atrial fibrillation or heart failure. CONCLUSION: The identification of high-risk patients and the provision of individualized perioperative monitoring are essential aspects of patient safety. Outpatient cardiological follow-up can improve outcomes.

Mechanisms of late arrhythmia recurrence after initially successful pulmonary vein isolation in patients with atrial fibrillation.

BACKGROUND: Catheter ablation is an effective treatment for atrial fibrillation (AF,) but arrhythmia recurrence occurs in a relevant number of patients. Mechanisms of late occurring arrhythmias after ablation procedures are not fully understood. We analyzed electrophysiological mechanisms of early and late arrhythmia recurrences in patients who underwent radiofrequency-based catheter ablation of AF. METHODS AND RESULTS: Consecutive patients who underwent repeat ablation procedures after initial pulmonary vein isolation (PVI) for symptomatic arrhythmia recurrence were analyzed. A total of 110 consecutive patients who underwent catheter ablation for paroxysmal (79%) or persistent AF (21%) were included. Forty-seven patients suffered from early arrhythmia recurrence (group #1: 3-24 months), 29 patients from mid-term arrhythmia recurrences (group #2: 2-5 years), and 34 patients from late arrhythmia recurrences (group #3: > 5 years). Electrical PV reconnection was found in 98% in group #1, 72% in group #2 and 56% in group #3 (p < .001). Mode of arrhythmia recurrence was organized tachycardia in 25%, 28%, and 65% of patients in groups #1, #2, and #3 (p = .001), respectively. Patients with late arrhythmia recurrence had more pronounced left atrial low voltage as compared to patients with early arrhythmia recurrence based on two published scoring system. CONCLUSION: Electrical PV reconnection was found in the majority of patients with early AF recurrence after PVI. In patients with late arrhythmia recurrences this mechanism may play an inferior role, with many patients presenting without PV reconnection, but with LA structural alterations. Thus, early and late occurring arrhythmia recurrence after catheter ablation may be the same symptom of different diseases.

Management of pericardial tamponade in the electrophysiology laboratory: results from a national survey.

BACKGROUND: Despite continued efforts to improve the safety of catheter ablation, pericardial tamponade remains one of its more frequent, potentially life-threatening complications. Management of cardiac tamponade is not standardized and uncertainties regarding acute treatment remain. METHODS: This survey sought to evaluate the management of cardiac tamponade in German EP centers via a standardized postal questionnaire. All 341 identified German EP centers were invited to return a questionnaire on their standards for the management of cardiac tamponade. RESULTS: A total of 189 German EP centers completed the questionnaire. Several precautions are followed to avoid pericardial tamponade: A minority of centers preclude very old patients (19%) or those with a high body mass index (30%) from ablation. Non-vitamin K antagonist oral anticoagulants are briefly paused in most centers (88%) before procedures, while vitamin K antagonists are continued. Pericardial tamponade is usually treated using reversal of heparin by applying protamine (86%) and pericardiocentesis under both, fluoroscopic and echocardiographic guidance (62%). A pigtail catheter is mostly inserted (97%) and autotransfusion of aspirated blood is performed in 47% of centers. The decision for surgical repair depends on different clinical and infrastructural aspects. The timing of reinitiation of anticoagulation widely differs between the centers. Approximately 1/3 of centers prescribe nonsteroidal anti-inflammatory agents, colchicine or steroids after pericardiocentesis. CONCLUSION: The present survey shows that the management of cardiac tamponade is still inhomogeneous in German ablation centers. However, multiple findings of this survey can be generalized and might guide especially less experienced operators and centers in their treatment and decision strategies.

Reverse structural left atrial remodeling and atrial tachycardia in patients with repeat ablation for atrial fibrillation.

BACKGROUND: Catheter ablation has been evolved to a cornerstone in the therapy of atrial fibrillation (AF); however, atrial tachycardias (AT) after AF ablation are still an important issue. Besides the electrical recurrence of atrial tachyarrhythmia after ablation, left atrial (LA) remodeling has received attention as a consequence of AF. OBJECTIVE: The aim of this study is to evaluate predictors for AT recurrence and LA remodeling in patients with repeat AF ablation procedures. METHODS AND RESULTS: One hundred thirteen patients who underwent repeat AF ablation with 3D electro-anatomical mapping system were evaluated. Mean age was 63.1 ± 9.3 years, and 2.3 ± 0.5 ablation procedures were performed during a time period of 22 [IQR 7;48] months. Reverse structural LA remodeling (LA volume decreased more than 15%) was observed in 25 (22.1%) patients. LA volume index (LAVI) during first procedure was the only predictor for positive reverse structural LA remodeling (hazard ratio (HR): 1.03, 95% CI: 1.00-1.07, p = .036) in multivariate analysis. Fifty-nine (52.2%) patients experienced only AF and 54 (47.8%) patients AT after first procedure. Female gender (HR: 5.21, 95% CI: 1.66-18.08, p = .006), LAVI (HR: 1.06, 95% CI: 1.02-1.11, p = .008) and LA scar percentage (HR: 1.08, 95% CI: 1.02-1.17, p = .019) were independent significant predictors for AT recurrence in multivariate analysis. CONCLUSIONS: Reverse structural LA remodeling occurred in a quarter of patients with repeat ablation procedures for AF. Only larger LAVI during first procedure predicted reverse structural LA remodeling. Half of the patients experienced AT between first and last ablation procedure. Female gender, larger LAVI and larger scar area were significant predictors for AT after catheter ablation for AF.

Pulsed-field ablation-based pulmonary vein isolation: acute safety, efficacy and short-term follow-up in a multi-center real world scenario.

PURPOSE: Pulsed-field ablation (PFA) is a new energy source to achieve pulmonary vein isolation (PVI) by targeted electroporation of cardiomyocytes. Experimental and controlled clinical trial data suggest good efficacy of PFA-based PVI. We aimed to assess efficacy, safety and follow-up of PFA-based PVI in an early adopter routine care setting. METHODS: Consecutive patients with symptomatic paroxysmal or persistent atrial fibrillation (AF) underwent PVI using the Farawave® PFA ablation catheter in conjunction with three-dimensional mapping at two German high-volume ablation centers. PVI was achieved by applying 8 PFA applications in each PV. RESULTS: A total of 138 patients undergoing a first PVI (67 ± 12 years, 66% male, 62% persistent AF) were treated. PVI was achieved in all patients by deploying 4563 applications in 546 PVs (8.4 ± 1.0/PV). Disappearance of PV signals after the first application was demonstrated in 544/546 PVs (99.6%). More than eight PFA applications were performed in 29/546 PVs (6%) following adapted catheter positioning or due to reconnection as assessed during remapping. Mean procedure time was 78 ± 22 min including pre- and post PVI high-density voltage mapping. PFA catheter LA dwell-time was 23 ± 9 min. Total fluoroscopy time and dose area product were 16 ± 7 min and 505 [275;747] cGy*cm2. One pericardial tamponade (0.7%), one transient ST-elevation (0.7%) and three groin complications (2.2%) occurred. 1-year follow-up showed freedom of arrhythmia in 90% in patients with paroxysmal AF (n = 47) and 60% in patients with persistent AF (n = 82, p = 0.015). CONCLUSIONS: PFA-based PVI is acutely highly effective and associated with a beneficial safety and low recurrence rate.

Antithrombotic therapy after angioplasty of pulmonary vein stenosis due to atrial fibrillation ablation: A two-center experience and review of the literature.

Background: Pulmonary vein stenosis (PVS) is a severe complication of atrial fibrillation (AF) ablation resulting in narrowing of affected pulmonary veins (PVs). Interventional treatment consists of angioplasty with or without PV stenting. The optimal postprocedural antithrombotic therapy is not known. Study aims: To investigate the impact of antithrombotic medical therapy on recurrence of PVS after PV angioplasty. Methods: A retrospective study of patients undergoing PV angioplasty with or without stent implantation in two German centers was performed. Postinterventional antithrombotic therapy consisted of either dual antiplatelet therapy (DAPT) or a combination of oral anticoagulation with single or dual antiplatelet therapy for 3-12 months after intervention. Angiographic follow-up was recommended 3, 6, and 12 months after intervention and in case of symptom recurrence. Results: Thirty patients underwent treatment of 42 PVS. After intervention, twenty-eight patients received triple therapy and 14 patients received dual therapy/DAPT; restenosis occurred in 5/22 (22.7%) patients with triple therapy and 8/14 (57.1%) patients with dual therapy/DAPT PV (p = .001). Estimated freedom from PV restenosis after 500 days was 18.8 ± 15.8% (dual therapy/DAPT) and 76.2 ± 10.5% (triple therapy) (p = .003). Univariate regression analysis revealed postprocedural medication as a significant risk factor for restenosis (p = .019). No bleeding events occurred regardless of applied antithrombotic therapy. Conclusion: Triple antithrombotic therapy after PV angioplasty is associated with less frequent restenosis as compared to dual antiplatelet therapy or a combination of anticoagulation and single antiplatelet therapy. No severe bleeding events occurred in patients on triple therapy. These findings need to be confirmed in larger patient cohorts.

Temperature-controlled ablation of the mitral isthmus line using the novel DiamondTemp ablation system.

Background: The novel DiamondTemp™ (DT)-catheter (Medtronic®) was designed for high-power, short-duration ablation in a temperature-controlled mode. Aim: To evaluate the performance of the DT-catheter for ablation of the mitral isthmus line (MIL) using two different energy dosing strategies. Materials and methods: Twenty patients with recurrence of atrial fibrillation (AF) and/or atrial tachycardia (AT) following pulmonary vein (PV) isolation were included. All patients underwent reisolation of PVs in case of electrical reconnection and ablation of a MIL using the DT-catheter. Application durations of 10 (group A, n = 10) or 20 s (group B, n = 10) were applied. If bidirectional block was not reached with endocardial ablation, additional ablation from within the coronary sinus (CS) was conducted. Results: In 19/20 (95%) patients, DT ablation of the MIL resulted in bidirectional block. Mean procedure and fluoroscopy time, and dose area product did not differ significantly between the two groups. In group B, fewer radiofrequency applications were needed to achieve bidirectional block of the MIL when compared to group A (26 ± 12 vs. 42 ± 17, p = 0.04). Ablation from within the CS was performed in 8/10 patients (80%) of group A and in 5/10 (50%) patients of group B (p = 0.34). No major complication occurred. Conclusion: Mitral isthmus line ablation with use of the DT-catheter is highly effective and safe. Longer radiofrequency-applications appear to be favorable without compromising safety.

Cryoballoon ablation guided by a novel wide-band dielectric imaging system.

Background and aim: To investigate the feasibility, acute efficacy, periprocedural safety, and procedural parameters of CB-based PVI guided by KODEX-EPD using different occlusion tool software versions. Methods and results: A total of 173 patients (60/173 (35%) paroxysmal AF, 64 ± 12 years, 66/173 (38%) female), underwent CB-based PVI guided by KODEX-EPD between August 2019 and October 2021. Acute PVI was achieved in all the patients. Total fluoroscopy time and dye volume were 13.9 [10.6-19.4] min and 47.5 [20-70] ml. Periprocedural complications occurred in 3 (2%) of the 173 patients. As part of the continued development program, different software versions were used, including 1.4.6 on 38 (22%), 1.4.6a on 33 (19%), 1.4.7 on 41 (24%), and 1.4.8 on 61 (35%) of the patients. Outcomes were compared between software versions by a univariate analysis. Sensitivity analyses were performed to account for confounders. Median fluoroscopy time was decreased by 6.4 min (37.3%), and the median volume of dye was decreased by 32.5 ml (52%) from versions 1.4.6 to 1.4.8. Software version was a significant predictor of fluoroscopy time and dye volume, while reductions in procedure duration and dose area product were observed but mainly explained via confounders. Conclusion: CB-based PVI guided by KODEX-EPD is feasible and safe. Progressive software improvements appear to be associated with lower fluoroscopy duration and dye use. Further studies are needed to evaluate the advantage of KODEX-EPD-guided compared to conventional CB-PVI.