Acute Procedural Success Rate Research Articles

P112 CLINICAL OUTCOMES OF LEFT ATRIAL APPENDAGE OCCLUSION WITH CONSCIOUS SEDATION WITHOUT ANESTHESIOLOGIST ON SITE: RESULTS FROM A MULTICENTER RETROSPECTIVE STUDY

Abstract Background Left atrial appendage (LAA) occlusion is an important therapeutic option to prevent cardioembolic stroke in patients with atrial fibrillation (AF) with contraindications for oral anticoagulation (OAC). It is usually performed with transesophageal echocardiography (TOE) under general anesthesia (GA). In this retrospective study we present a multicenter experience of LAA occlusion performed with conscious sedation (CS) without anesthesiologist on site. Methods We collected all the LAA occlusion procedures performed from October 2018 to May 2022. All the included patients underwent the procedure for OAC intolerance mainly due to bleeding with irreversible causes. All the procedures were performed with Watchman or Amulet LAA occluders under TOE and fluoroscopy guidance by two expert interventional cardiologists without anesthesiologist on site. CS was performed with a combination of midazolam and fentanyl. Results One hundred and fifteen patients (age 76.4 ± 7.6 year) with non–valvular AF (median CHA2DS2Vasc 4.4 ± 1.4) were included in the study. CS was performed using midazolam (mean dose 5.9 ± 2.1 mg), adding fentanyl (mean dose 52.8 ± 19.6 mcg) in case of poor tolerance of the procedure despite midazolam. Acute procedural success rate was of 99.2%. One patient suffered a cardiac tamponade, urgent necessity of cardiac surgery and died 5 days after procedure. Two patients (2.6%) had anemia with need for transfusion after interventions. A patient (0.8%) suffered from oropharynx hematoma due to TOE. One case (0,8%) of vascular access site pseudoaneurysm occurred. One case (0.8%) of device thrombosis at 3 months TOE follow–up was reported. One procedure (0.8%) result in large leak device (³5 mm), confirmed at TOE follow–up performed at 3 months follow–up. No thromboembolic complications were reported. One hundred and fourteen (99.2%) patients stopped dual antiplatelet therapy within 12 months. In a follow–up of 10 ± 9 months one case of stroke (0.8%) and one case (0.8%) of transient ischemic attack (TIA) occurred. Conclusion LAA occlusion performed under CS and without the presence of anesthesiologist in cath–lab appear to be safe and effective. It can be an attractive alternative to (GA) because of lower medical staff needed and organizational effort required. In our retrospective study the success rate and the incidence of adverse events appear to be comparable with those of previous studies on the topic of LAA occlusion

PO-03-029 LEFT BUNDLE BRANCH AREA PACING LEARNING CURVE AND OUTCOMES IN A BEGINNER IMPLANTER

Left bundle branch area pacing (LBBAP) is a rapidly growing conduction system pacing technique. However, little is known about the learning curve of LBBAP implants in a beginner implanter. We sought to determine acute procedural success rate, implant characteristics, and complications of a single operator implanting LBBA pacing devices in his first year of unsupervised practice. All patients who underwent pacemaker and CRT device implants at our center by a single operator (TC) were reviewed. LBBAP was defined as the presence of R’ in lead V1, and LV activation time (LVAT) <= 80 msec (stim to peak in V6) in the paced QRS complex. Charts were retrospectively reviewed to determine rates of LBBA capture, procedure duration, fluoroscopy time, lead dislodgement, and lead revision rates. LBBA pacing was attempted in 80 patients. Medtronic C315 sheath was used to deliver a Medtronic 3830 lead to the LBBA in all cases. LBBA capture was obtained in 69/80 (86%) patients. Mean paced QRS duration was 131 +/- 13 msec. and mean LVAT was 66 +/- 11 msec. For the first 20 implants, mean procedure duration was 104 +/-32 minutes, and mean fluoroscopy time was 11 +/- 6 minutes. Subsequent 60 implants had significantly lower mean procedure duration (82 +/- 21 mins, p < 0.01) and fluoroscopy time (8 +/- 4 mins, p = 0.01). Overall, mean procedure duration was 88 +/- 26 minutes, and mean fluoroscopy time was 9 +/- 5 minutes. Rate of LBBA capture increased from 70% for the first 20 implants to 92% for the last 60 implants. No significant differences were observed in QRS duration and LVAT time between the first 20 and last 60 implants. Three lead dislodgements occurred, all of which occurred prior to the 15th procedure. One patient required lead revision for increasing pacing thresholds. In this single center, retrospective study of a single operator in his first year of unsupervised practice, LBBA pacing was achieved in majority of patients. Rate of lead dislodgement and need for lead revision were low. Procedural success rate increased while procedure duration, fluoroscopy use, and complications decreased after 20 implants.

Outcomes of Percutaneous Coronary Interventions for Long Diffuse Coronary Artery Disease with Extremely Small Diameter

The optimal percutaneous coronary intervention (PCI) strategy and clinical outcomes of long lesions with an extremely small residual lumen remain unclear. This study aimed to assess the efficacy of a modified stenting strategy for diffuse coronary artery disease (CAD) with an extremely small distal residual lumen. 736 Patients who received PCI using second-generation drug-eluting stents (DES) ≥38 mm long were retrospectively included and categorized into an extremely small distal vessel (ESDV) group (≤2.0 mm) and a non-ESDV group (>2.0 mm) according to the maximal luminal diameter of the distal vessel (dsDMax). A modified stenting technique was applied by landing an oversized DES in the distal segment with the largest luminal diameter and maintaining the distal stent edge partially expanded. The mean dsDMax and stent lengths were 1.7 ± 0.3 mm and 62.6 ± 18.1 mm in the ESDV group and 2.7 ± 0.5 mm and 59.1 ± 16.0 mm in non-ESDV groups, respectively. The acute procedural success rate was high in both the ESDV and non-ESDV groups (95.8% and 96.5%, p = 0.70) with rare distal dissection (0.3% and 0.5%, p = 1.00). The target vessel failure (TVF) rate was 16.3% in the ESDV group and 12.1% in the non-ESDV group at a median follow-up of 65 months without significant differences after propensity score matching. PCI using contemporary DES with this modified stenting technique is effective and safe for diffuse CAD with extremely small distal vessels.

Clinical Course and Electrophysiological Characteristics of Permanent Junctional Reciprocating Tachycardia in Children.

In this study, we aimed to evaluate the clinical aspects, electrophysiological studies, and ablation results of permanent junctional reciprocating tachycardia in children. The study comprised 29 pediatric patients diagnosed with permanent junctional reciprocating tachycardia between 2011 and 2021 in 2 pediatric electrophysiology centers. From the file records, the basic demographic characteristics of the patients, as well as electrocardiographic and echocardiographic findings, were acquired retrospectively. The medical treatment and responses of the patients throughout follow-up, as well as the electrophysiological study and ablation data of the patients who had electrophysiological study, were assessed. The mean age at diagnosis of the patients was 3.13 ± 4.43 (0-18) years and the mean weight was 18.22 ± 19.68 (3.8-94) kg. Eighteen patients (62.1%) were girls. Eleven patients (38%) developed tachycardia-induced cardiomyopathy. Tachycardia was incessant in 15 patients (51.7%). In total, 22 patients required 26 ablation procedures. Tachycardia-induced cardiomyopathy and multidrug-resistant tachycardia were the most prevalent indications for ablation. The right posteroseptal pathway was detected in 18 patients (81.8%). The acute procedure success rate was 100% (22/22). The recurrence rate was 18% (4/22) and 3 of them underwent successful ablation again. The overall success percentage was 95.4% (21/22). None of the patients had any complications. The mean follow-up period was 4.39 ± 3.05 years. Although permanent junctional reciprocating tachycardia is uncommon, it is often persistent, resistant to medical treatment, and associated with a substantial risk of tachycardia-induced cardiomyopathy. Catheter ablation can be performed on these patients at any age, with minimal risk of complications and a high success rate. It is crucial to keep monitor of the patients' recurrence.

Long-Term Follow-Up of Catheter Ablation for Premature Ventricular Complexes in the Modern Era: The Importance of Localization and Substrate.

Background: Large-scale studies evaluating long-term recurrence rates in both idiopathic and non-idiopathic PVC catheter ablation (CA) patients have not been reported. Objective: To evaluate the efficacy and safety of idiopathic and non-idiopathic PVC CA, investigating the predictors of acute and long-term efficacy. Methods: This retrospective multicentric study included 439 patients who underwent PVC CA at three institutions from April-2015 to December-2021. Clinical success at 6 months' follow-up, defined as a reduction of at least 80% of the pre-procedural PVC burden, was deemed the primary outcome. The secondary aims of the study were: clinical success at the last available follow-up, predictors of arrhythmic recurrences at long-term follow-up, and safety outcomes. Results: The median age was 51 years, with 24.9% patients being affected suffering from structural heart disease. The median pre-procedural PVC burden was 20.1%. PVCs originating from the RVOT were the most common index PVC observed (29.1%), followed by coronary cusp (CC) and non-outflow tract (OT) LV PVCs (23.1% and 19.0%). The primary outcome at 6 months was reached in 85.1% cases, with a significant reduction in the 24 h% PVC burden (-91.4% [-83.4; -96.7], p &lt; 0.001); long-term efficacy was observed in 82.1% of cases at almost 3-year follow-up. The presence of underlying structural heart disease and non-OT LV region origin (aHR 1.77 [1.07-2.93], p = 0.027 and aHR = 1.96 [1.22-3.14], p = 0.005) was independently associated with recurrences. Conclusion: CA of both idiopathic and non-idiopathic PVCs showed a very good acute and long-term procedural success rate, with an overall low complication. Predictors of arrhythmic recurrence at follow-up were underlying structural heart disease and non-OT LV origin.

A Novel Puncturable Atrial Septal Defect Occluder: The Results of Preclinical Experiment and First-in-Human Study

ReAces is a novel puncturable transcatheter atrial septal defect occluder. The device success rate was 100% (n=14 of 14) in the animal experiment. Four swine successfully received puncture of the device 60days after implantation of the device. The acute procedure success rate in the 10 patients was 100%. Transthoracic echocardiography examination showed that the devices were well positioned with no residual shunt, and the area of central portion of occluder was substantially thin. It is safe and effective to use ReAces for closure of secundum atrial septal defect, and puncture the atrial septum at the portion of the device is feasible.

Pulsed field ablation for atrial fibrillation: acute procedural efficacy and safety of an initial German multicenter experience

Abstract Background Pulsed field ablation (PFA) is a novel non-thermal energy source to conduct catheter ablation of atrial fibrillation (AF). However, real-world multi-center data regarding acute procedural efficacy and safety is sparse. Purpose To study acute procedural success and safety in patients undergoing PFA for catheter ablation of AF in a multicenter registry. Methods Consecutive paroxysmal and persistent AF patients undergoing PFA-based catheter ablation using a multispline catheter were enrolled. The cohort included first and repeat ablation procedures. Procedural parameters, acute success and in-hospital safety were evaluated. A follow-up of all patients was conducted. Results Five German centers enrolled a total of 154 patients undergoing PFA in this study. Mean age was 68±12 years, median CHA2DS2-VASc Score was 3 (Q1-Q3: 2–4). Patients suffered from paroxysmal AF (n=55; 36%), persistent AF (n=93; 60%) and consecutive atrial tachycardias (AT) due to previous CA (n=6; 4%). The median left atrial (LA) PFA and total procedure times were 33 (Q1-Q3: 24–53) and 90 (Q1-Q3: 73–116) minutes, respectively. Mean LA PFA fluoroscopy and total fluoroscopy times were 12.1±5.5 and 20.2±8.7 minutes. Of all 154 procedures, 130 (84%) were index ablation procedures with isolation of pulmonary veins (PVI) only and 24 (16%) were repeat procedures (including re-PVI and ablation of consecutive AT). Acute PV reconnection following primary PVI and the initial set of PFA-applications was found in 20/130 (15%) patients, necessitating additional PFA ablation. Finally, successful PFA-guided PVI was achieved in all patients. Additional PFA lesion sets (including LA posterior wall isolation, anterior ablation, mitral isthmus ablation) were applied in 17/154 (11%) patients. Complications occurred in a total of 6/154 (3.8%) patients (including three groin site complications, two pericardial tamponades, one transient coronary spasm without sequela). The follow up data is still being assessed and will be provided by the time of the ESC 2022 meeting. Conclusion PFA performed in patients with atrial fibrillation demonstrates high acute procedural success rates and a favorable safety profile in this first real-world multicenter registry. Funding Acknowledgement Type of funding sources: None.

Initial Clinical Experience With a Novel8-Spline High-Resolution MappingCatheter.

The Octaray (Biosense Webster) is a novel, multispline mapping catheter with 48 closely spaced microelectrodes enabling high-resolution electroanatomical mapping. This study sought to report the initial clinical mapping experience with this novel catheter in a variety of cardiac arrhythmias and to compare the mapping performance with the 5-spline Pentaray. Fifty consecutive procedures among 46 patients were retrospectively analyzed regarding safety, efficacy, and acute procedural success defined as termination or noninducibility of clinical tachycardia, conduction block across an ablation line, or pulmonary vein isolation. In addition, another 10 patients with sustained atrial tachycardia mapped with the 5-spline catheter (2-5-2 spacing) or the novel 8-spline catheter (2-2-2-2-2 spacing) were analyzed. Left atrial and ventricular mapping by either transseptal (n=41) or retroaortic (n=2) access was feasible without any complications related to the multispline design of the novel catheter. The acute procedural success rate was 94%. In sustained atrial tachycardia compared with the 5-spline catheter, the novel 8-spline catheter recorded more electrograms per map (3,628 ± 714 vs 11,350 ± 1,203; P&lt; 0.001) in a shorter mapping time (13 ± 2 vs 9 ± 1minutes; P=0.08) resulting in a higher point density (18 ± 4 vs 59 ± 10 electrograms/cm²; P&lt; 0.01) and point acquisition rate (308 ± 69 vs 1,332 ± 208 electrograms/min.; P&lt; 0.01). In this initial experience, mapping with the novel catheter was safe and efficient with a high electroanatomical resolution. In sustained atrial tachycardia the novel 8-spline catheter demonstrated a marked increase in point density and mapping speed compared with those of the 5-spline catheter. These initial results should be validated in a larger multicenter cohort with longer follow-up.

Zero-fluoroscopy catheter ablation of supraventricular tachycardias in pediatric population

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Catheter ablation (CA) of supraventricular tachycardias (SVTs) in pediatric patients is conventionally performed with the aid of X-ray fluoroscopy. Usage of the three-dimensional (3D) electro-anatomical mapping (EAM) system and the intracardiac echocardiography (ICE) enables zero-fluorscopy ablation, eliminating the harmful effects of the radiation (1-3). Purpose We retrospectively analyzed the feasibility, effectiveness and safety of zero-fluoroscopy radiofrequency and cryoablation of various types of SVTs in pediatric patients. Methods In this retrospective study, we analyzed consecutive pediatric patients who underwent CA procedure due to SVT in our institution from April 2014 to October 2021. All procedures were performed completely without the use of fluoroscopy. A 3D EAM system and ICE were used as the principal modes of catheter visualisation. Left-sided procedures were done with ICE guided transseptal approach. Radiofrequency was the principal energy source, while cryoablation was used for arrhythmia substrates in the proximity of the conduction system. Results The study included 174 consecutive patients (69/174 (66%) female; 12.5 ± 3.9 years; 19.2 ± 3.6 kg/m2). Altogether 176 SVTs were diagnosed and treated. Atrio-ventricular nodal reentry tachycardia (AVNRT) was diagnosed in 45% of cases (80/176), atrio-ventricular reentry tachycardia (AVRT) in 47% (82/176), focal atrial tachycardia (AT) in 7% (13/176), typical atrial flutter (AFL) was treated in only one patient, while 2 patients had multiple arrhythmias (AVNRT and AVRT). In total, 202 procedures were performed. Radiofrequency ablation was performed in 76% (154/202), cryoablation in 20% (40/202) and both in 4% (8/202) of procedures. The acute procedural success rate was 96% (195/202). Procedural success rate was 99% (79/80) for AVNRT, 94% (77/82) for AVRT, 92% (12/13) for AT, and 100% (1/1) for AFL, respectively. There were no major complications in our study group. Follow-up was complete in 99% (172/174) of patients. During the follow-up period of a median of 316 days (181 - 747), 98% of patients were arrhythmia free. On average, 1.16 procedures per patient were performed with the long-term success rate of 99% (79/80), 98% (80/82), 100% (13/13) and 100% (1) for AVNRT, AVRT, AT, and AFL, respectively. Conclusion Zero-fluoroscopy CA of various types of SVTs in pediatric population is a feasible, effective, and safe treatment option.

Improving procedural success rate of retrograde ethanol infusion in the vein of Marshall

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Retrograde ethanol infusion in the vein of Marshall (VOM) is a relatively new adjunctive therapy of atrial arrhythmias. The VOM is an epicardial left atrial vein. Its surrounding autonomic ganglia and proarrhythmogenic muscle fibers are accepted extrapulmonary triggers of AF and can be ablated by retrograde ethanol infusion. This facilitates the achievement of bidirectional mitral isthmus block. Moreover, it seems to improve outcomes in terms of rhythm stability if performed in addition to RF ablation in persistent atrial fibrillation. However, retrograde ethanol infusion in the vein of Marshall (VOM) can be technically challenging. Technical improvement of the procedure has the potential of higher primary success rate and therefore may secondary lead to better outcome of interventional therapy of persistent AF. Purpose International experienced centers achieve an acute procedural success rate around 85%. The purpose of our investigation was to study the impact of adding procedural techniques to the standard procedure as described before on the acute procedural success. Methods We analyzed all ethanol infusions in the VOM performed in our department between Nov 2019 and Nov 2021. Our standard approach resembles the technique published before primarily performed via a transfemoral access. If a VOM is angiographically not visible using the standard approach, we perform a rotational angiography. In case of negative angiography of the VOM, we try the atraumatic wiring assuming a typical anatomical location of the vein draining just proximal of the valve of Vieussens into the CS. If very proximal location of the VOM in the CS led to an instable catheter via transfemoral access we used transjugular access and a CRT-sheath. We collected data on additionally used techniques and their value for acute procedural success. All data are given as mean ± SD or number/percentages. Results Ethanol infusions were mostly performed as standalone procedures (136/147, 92,5%) or in a minority of cases as adjunctive therapy during RF-ablation. The ethanol infusion was succesful in 143 of the 147 patients (97%). In 21 patients (14%) extention of the technique exceeding the standard approach led to a succesful procedure. A rotational angiography revealed a previously not visible VOM in 5 patients (3,4%). Atraumatic wiring of the angiographic negative VOM in typical position was successful in 11 patients (7,5%). 5 patients (3,4%) benefitted from a transjugular venous access. Periprocedural complications were rare. We observed no vascular access site complications or pericardial effusion/tamponade. One patient suffered from a transient ischemic attack one week after the procedure. Conclusions Acute procedural success of ethanol infusion in the VOM amounted to 83% using the standard approach. We were able to improve the success rate to 97% by adding further imaging and modifying the technical approach while the positive safety profile remained.

Efficacy and Safety of Zero-Fluoroscopy Approach during Catheter Ablation of Accessory Pathway.

Background: Catheter ablation (CA) is a safe and efficient treatment in patients with an atrioventricular accessory pathway (AP). Electroanatomical mapping (EAM) systems are useful during CA of AP, especially for reducing fluoroscopy. There are limited data about the feasibility of CA procedures performed with the use of the EAM system entirely without fluoroscopy in adults with AP. The aim of the study is to assess the feasibility, efficacy and safety of CA with the use of EAM without fluoroscopy, compared to CA with EAM and fluoroscopy in patients with AP. Methods: The study included 83 consecutive patients (age 38.25 ± 15.8 years), who were subjected to CA for AP. In 40 patients CA was performed with the use of EAM without fluoroscopy (EAM group), and in 43 patients CA was performed with EAM and fluoroscopy (control group). Baseline characteristics, procedure parameters and complications were obtained from the medical records. Data on permanent success rate was obtained after the mean follow-up time of 1 year. Primary outcomes were acute procedural success rate, long term success rate at 1-year follow-up and complications. Secondary outcomes were the procedure time and number of applications. Results: There were no statistically significant differences in baseline characteristics between the groups, except for the AP locations. Right-sided AP was more common in the EAM group, while left-sided AP was more common in the control group (p = 0.007 and p = 0.004, respectively). Acute procedural success was achieved in 38 patients (95.0%) in the EAM group and in 39 patients (90.7%) in the control group (p = 0.449). Long term success rate was achieved in 36 patients (90.0%) in the EAM group and in 36 (83.7%) patients in the control group (p = 0.399). There was one minor complication in the form of RBBB in the EAM group (p = 0.138). The mean procedure time was shorter in the EAM group compared to the control group (93.0 ± 58.3 min vs. 127.6 ± 57.5 min; p = 0.009). Conclusions: CA of both right-sided and left-sided AP completely guided by EAM without the use of fluoroscopy is feasible, safe and effective.

Very long-term outcomes after catheter ablation of atrioventricular nodal reentrant tachycardia: How does cryoenergy differ from radiofrequency?

Either cryoenergy or radiofrequency can be used during atrioventricular nodal reentrant tachycardia (AVNRT) ablation. There is still limited data comparing their respective long-term efficacy (> 1 year). This study sought to compare the very long-term outcomes of AVNRT ablation using radiofrequency or cryotherapy. We retrospectively included all patients who had undergone a first AVNRT ablation in our institution between January 2010 and December 2017. The primary endpoint was recurrence of documented AVNRT. The study population consisted of 409 patients (274 females, mean age 49.9 year-old). Ablation was performed using cryoenergy in 260 patients and radiofrequency in 149. High acute procedural success rate (> 98%) was obtained and no permanent AV block was observed using both techniques. During a mean follow-up of 3.3 ± 2.3 years, documented AVNRT recurrence occurred in 24 (9.2%) and 4 patients (2.7%) in the cryoablation and radiofrequency group respectively. The risk of AVNRT recurrence was significantly higher in the CA group as compared to the RF group (hazard ratio = 3.7, 95% CI: 1.3 to 5.9). Most of the recurrences after cryoablation occurred between 1- and 6-year follow-up (14/24; 58.3%), with 1/3rd of late recurrences after 3-year follow-up. In multivariable analysis, only Koch's triangle anatomical variant was associated with AVNRT recurrence after cryoablation (hazard ratio = 6.7, 95% CI: 2.7–16.3) ( Fig. 1 ). While AVNRT recurrence rates were similar at one year of follow-up regardless of the energy used, long-term efficacy appeared higher after radiofrequency ablation. Strikingly, recurrences occurred much later after cryotherapy compared to radiofrequency ablation.

Cardiovascular magnetic resonance pulmonary perfusion for guidance of interventional treatment of pulmonary vein stenosis

BackgroundPulmonary vein (PV) stenosis represents a rare but serious complication following radiofrequency ablation of atrial fibrillation with a comprehensive diagnosis including morphological stenosis grading together with the assessment of its functional consequences being imperative within the relatively narrow window for therapeutic intervention. The present study determined the clinical utility of a combined, single-session cardiovascular magnetic resonance (CMR) imaging protocol integrating pulmonary perfusion and PV angiographic assessment for pre-procedural planning and follow-up of patients referred for interventional PV stenosis treatment.MethodsCMR examinations (cine imaging, dynamic pulmonary perfusion, three-dimensional PV angiography) were performed in 32 consecutive patients prior to interventional treatment of PV stenosis and at 1-day and 3-months follow-up. Degree of PV stenosis was visually determined on CMR angiography; visual and quantitative analysis of pulmonary perfusion imaging was done for all five lung lobes.ResultsInterventional treatment of PV stenosis achieved an acute procedural success rate of 90%. Agreement between visually evaluated pulmonary perfusion imaging and the presence or absence of a ≥ 70% PV stenosis was nearly perfect (Cohen’s kappa, 0.96). ROC analysis demonstrated high discriminatory power of quantitative pulmonary perfusion measurements for the detection of ≥ 70% PV stenosis (AUC for time-to-peak enhancement, 0.96; wash-in rate, 0.93; maximum enhancement, 0.90). Quantitative pulmonary perfusion analysis proved a very large treatment effect attributable to successful PV revascularization already after 1 day.ConclusionIntegration of CMR pulmonary perfusion imaging into the clinical work-up of patients with PV stenosis allowed for efficient peri-procedural stratification and follow-up evaluation of revascularization success.

Zero-fluoroscopy ablation in patients with cardiac electronic implantable devices.

Utilizing a three-dimensional (3-D) mapping system and intracardiac echocardiography (ICE) has allowed ablation procedures with less or without fluoroscopy; however, there is limited data for patients with cardiac electronic implantable device (CIED) leads regarding the suspected risk of lead injury. Therefore, we sought to explore technics to perform safe trans-septal approach and catheter manipulation technique in patients with CIED leads. This study comprised 49 consecutive patients (59% males, median 73 years old) with CIED who underwent catheter ablation for supraventricular tachycardia requiring the trans-septal approach, 15 without fluoroscopy (zero-fluoro group), and 34 with fluoroscopy (conventional-fluoro group), between July 2019 and April 2021. All procedures were performed under a 3-D mapping system and ICE guidance. We compared the differences in treatment and development of complications between the two groups. The procedures were for atrial fibrillation (82%) and atrial tachycardia (76%). Coronary sinus catheter insertion and the trans-septal procedure were successfully performed in all patients. The median time from venipuncture to trans-septal procedure (zero-fluoro vs. conventional-fluoro group: 28 [18-37] min vs. 24 [21-31] min, p = .70), total procedure time (231 [142-274] minvs. 175 [163-225] min, p = .63), and the acute procedural success rate (100% vs. 97%, p = 1.00) did not differ between both groups. No patient showed lead-related complications in both groups. This is the first study to show zero-fluoro ablation for supraventricular arrhythmia using 3-D mapping and ICE in patients with CIED leads was feasible under careful catheter manipulation.

204 Permanent his bundle pacing using stylet-driven lead in patients with right atriomegaly: a single-centre experience

Abstract Aims His bundle pacing (HBP) is becoming an increasing widespread approach for physiological pacing. However, successful HBP procedure could be hampered by limited implantation tools especially in challenging anatomies. We aimed to report our experience with HBP technique using a novel stylet-driven lead system in patients with right atriomegaly. Methods and results Consecutive patients with right atrium (RA) volume &amp;gt;25 ml/m2 in men and &amp;gt;21 ml/m2 in women who underwent permanent HBP for standard indications were enrolled from March 2020 to March 2021. The tool of first choice for HBP attempt was a stylet-driven lead (Solia S 60, Biotronik) delivered via a dedicated introducer sheath (Selectra 3D, Biotronik). The acute, 1-month and 6-month procedural success rates were assessed. We enrolled 24 patients [median age: 75 (70–79) years, 85% men] with an average RA volume of 50.7 ± 7.8 ml/m2. At implant, conduction system pacing using stylet-driven lead was achieved in 21 patients (87%): 12 (50%) selective HBP, 6 (25%) non-selective HBP, and 3 (12.5%) left bundle branch area pacing. In the three failures, HBP was further attempted with a lumen-less lead with fixed helix (SelectSecure 3830, Medtronic) with final procedural success in two cases. In the successful cases, there was a significant reduction of QRS duration between paced and spontaneous beats [152.5 (130–167.5) ms vs. 130 (122.5–137.5) ms, P = 0.003]. No lead dislodgment nor significant pacing threshold increase was observed at 1-month (1.30 ± 0.76 V@0.4 vs. 1.32 ± 0.80 V@0.4 ms, P &amp;gt; 0.9) and 6-month follow-up (1.30 ± 0.76 V@0.4 vs. 1.38 ± 0.97 V@0.4 ms, P = 0.66). Conclusions In patients with right atriomegaly, the novel stylet-driven lead system showed high implant success rates with stable pacing thresholds.

696 Moderate sedation for transesophageal echocardiography guidance of percutaneous left atrial appendage closure: the MID-DEX protocol

Abstract Aims Left atrial appendage closure (LAAC) is usually performed under general anesthesia to allow prolonged transesophageal echocardiography (TEE) guidance. There is scarce knowledge about the feasibility and safety of moderate conscious sedation (MCS) in LAAC. We aimed to assess the feasibility, effectiveness and safety of an innovative MCS protocol of dexmedetomidine plus midazolam (MID-DEX), in a retrospective population of LAAC patients. Methods and results A total of 100 patients underwent LAAC with MCS using the MID-DEX protocol between May 2019 and January 2021 in a single centre. Clinical and procedural outcomes of these patients have been collected in the context of a retrospective registry on LAAC with the Watchman FLX device. All patients were treated preoperative with Dex, administered with initial bolus infusion (1.0 mcg/kg) in 10 min, then i.v. infusion was maintained throughout the LAAC procedure (0.2–1.0 μg/kg/h), tailored on patient’s frailty (advanced age, low body mass index) and haemodynamic status (BP, HR). Midazolam was administered to patients after Dex bolus, to induce sedation and to ease probe insertion, according to patient age and respiratory status (from 2.5 to max 10 mg). The ease of insertion of the TEE probe (one very easy—five impossible), and the duration of the TEE (m′) were recorded. Additional variables were: total amount of each drug given, time to recovery from sedation. After procedure a verbal survey about the quality of sedation, level of comfort, recall of the procedure, and future acceptance of this type of sedation was administered. The operators also rated the procedural conditions on a scale of 1–5 (5 = excellent). Mean patient age was 78.5 ± 6.96 years and 34% were women. The mean LVEF was 62.9 ± 8.9%. All patients underwent LAAC under MID-DEX MCS protocol with an acute procedural success rate of 100%. Ninety patients (90%) successfully underwent TEE under MCS; in 10 patients ICE guidance was required. Fluoroscopic time was 31 ± 21.7 min. The median required dosage of Dex infusion was 0.08–0.09 μg/kg/h and midazolam was 6.2 ± 2.4 mg. No complications were observed from MCS. There was no need for conversion to GA during the procedure. We observed five cases of bradycardia (solved by reducing to half Dex infusion) and three of hypotension (only two requiring Ringer’s solution infusion). Echocardiographist rated procedural conditions as perfect (5) in 85% of cases and good (4) in 6%. Interventionalist rated procedural comfort with 5 (excellent) in 90% of cases and 4 (good) in 3%. Patients satisfaction was high with best rate (5) in 80% with 5% of 4 (good); 12% described the procedure as fair, without memory of discomfort. Conclusions LAAC is safe and effective when performed under MCS. Thus, applying MCS may simplify the LAAC procedure, as well as reduce procedural time and procedural costs, while increasing overall patient and physician satisfaction.

Abstract 11458: Temporal Changes in Mitral Regurgitation After Percutaneous Mitral Valve Repair with MitraClip for Functional Mitral Regurgitation in Patients with Atrial Fibrillation

Background: Recently, percutaneous mitral valve (MV) repair has been increasingly performed for functional mitral regurgitation (FMR). However, few studies have examined the effectiveness of percutaneous MV repair for atrial FMR (AFMR). The aim of this study is to compare the effectiveness of MitraClip implantation between patients with AFMR and ventricular FMR (VFMR). Methods: We retrospectively reviewed 113 grade 3 to 4+ FMR patients with persistent atrial fibrillation or atrial flutter who underwent MitraClip implantation. We classified the patients into 2 groups; 43 patients with preserved left ventricular (LV) ejection fraction (LVEF) ≥ 50% and normal LV wall motion were defined as AFMR. 70 patients with LV dysfunction (LVEF &lt; 50 %) or LV wall motion abnormality were defined as VFMR. Transthoracic echocardiography (TTE) follow-up was performed at approximately 1-day, 1-month and 1-year after the procedure. Results: The percentage of grade 4+ mitral regurgitation (MR) was 53% in AFMR and 49% in VFMR at baseline (P=0.61). Acute procedural success rate was similar between AFMR and VFMR (95.3% vs. 97.1%, P=0.49). The median period of 1-month and 1-year follow-up TTE were 33 [interquartile range (IQR): 28-36] days and 356 (IQR: 248-399) days in AFMR, and 34 (IQR: 30-38) days and 366 (IQR: 336-415) days in VFMR, respectively. The percentage of grade 3 or 4+ MR at 1-day, 1-month, and 1-year after the procedure were 4.7% (2/43), 10% (3/30), and 5.6% (1/18) in AFMR, and 2.9% (2/70), 7.3% (4/55), and 2.9% (1/35) in VFMR (P=0.49, 0.48, and 0.57, respectively, AFMR vs. VFMR at the same follow-up point). The rates of redo MitraClip or MV surgery for recurrent MR within 1-month and between 1-month/1-year were 0% and 9.3% in AFMR, and 1.4% and 1.4% in VFMR. The percentage of New York Heart Association functional class III or IV at baseline, 1-month, and 1-year after the procedure were 90.7% (39/43), 23.3% (7/30), and 33.3% (6/18) in AFMR and 97.1% (68/70), 27.3% (15/55), and 22.9% (8/35) in VFMR (P=0.15, 0.69, and 0.41, respectively, AFMR vs. VFMR at the same follow-up point). Conclusions: In our series, MitraClip implantation had comparable therapeutic effect on both MR severity and heart failure symptoms between patients with AFMR and VFMR.

Comparison of atrial fibrillation ablation using cryoballoon versus radiofrequency in patients with left common pulmonary veins: mid-term follow-up results.

Cryoballoon (CB) and radiofrequency (RF) ablation techniques have similar outcomes for pulmonary vein isolation (PVI) in patients with atrial fibrillation (AF). However, there is limited data about the impact of different ablation strategies in patients with left common pulmonary vein (LCPV). Our aim was to compare the safety and efficacy of RF and CB ablation in AF patients with LCPV. One hundred and twenty-seven (n = 80 CB and n = 47 RF) AF patients with LCPV detected by preprocedural computerized tomography (CT) were included in the study. Ostial dimensions and trunk distance were measured in all patients. Atrial tachyarrhythmia (ATa) recurrence was defined as detection of AF, atrial flutter, or atrial tachycardia (≥ 30s) after a 3-month blanking period. There was no significant difference in acute procedural success rates for PVI (97.5% in CB and 97.9% in RF, respectively, P = 0.953) and complication rates were similar between the groups (6 (7.5%) in CB and 4 (8.5%) in RF, respectively, P = 1.000). During a median follow-up of 20.7 (4.8-50.2) months for CB and 20.5 (6.2-36.0) months for RF, ATa recurrence was 35.0% and 38.2%, respectively (P = 0.777). Multivariate analysis did not reveal any of the morphologic parameters of LCPV as a significant predictor of ATa recurrence. Our findings demonstrated that both CB and RF ablation techniques have similar efficacy and safety in AF patients with LCPV during the mid-term follow-up.

Long-term outcomes and periprocedural safety and efficacy of percutaneous left atrial appendage closure in a United Kingdom tertiary center: An 11-year experience.

Left atrial appendage occlusion (LAAO) has been widely adopted as a strategy for stroke prevention in patients with atrial fibrillation ineligible for oral anticoagulation. The purpose of this study was to explore longer-term "real-world" safety and efficacy outcomes in patients undergoing LAAO given varied practices in antithrombotic regimens and adoption of same-day discharge. Analysis of acute procedural and long-term outcome data was performed for all patients undergoing LAAO implant in a United Kingdom tertiary center over an 11-year period. Rates of adverse events were calculated and compared to predicted rates in historical cohorts according to CHA2DS2-VASc and HAS-BLED scores. Device implantation was attempted in 229 patients, with an acute procedural success rate of 98.2% and low rate of major procedural complications of 2.6% at 30 days, including 1.3% procedure-related mortality. In the last year of enrollment, 75% of patients were discharged on the same day of the procedure. A strategy of early cessation of antithrombotic therapy was adopted, with a low rate of device-related thrombus. Over total follow-up of 889 patient-years, there were low rates of thromboembolic events (2.2/100 patient-years) and of significant bleeding events (intracranial bleed 0.6/100 patient-years; nonprocedural major bleeding 2.3/100 patient-years). LAAO with a same-day discharge strategy and early cessation of antiplatelet therapy seems to be safe and effective in reducing the risk of stroke and major bleeding over mean follow-up approaching 4 years. Although these data are reassuring, results from randomized trials with strict shorter periods of postprocedural antithrombotic therapy are eagerly awaited.

Long-Term Outcomes of Near-Zero Radiation Ablation of Paroxysmal Supraventricular Tachycardia: A Comparison With Fluoroscopy-Guided Approach.

This study aimed to assess the long-term outcomes of minimally fluoroscopic approach (MFA) compared with conventional fluoroscopic ablation (ConvA) in terms of recurrences of arrhythmia and long-term complications. Catheter ablation (CA) of supraventricular tachycardia (SVT) with an MFA, under the guidance of electroanatomic mapping (EAM) systems, results in a significant reduction in exposure to ionizing radiations without impairing acute procedural success and complication rate. However, data regarding long-term outcomes of MFA compared with ConvA are lacking. This is a retrospective observational study. All patients undergoing MFA CA of SVT (atrioventricular nodal re-entrant tachycardia and atrioventricular re-entrant tachycardia) between 2010 and 2015 were enrolled and were compared with matched subjects (1 MFA: 2 ConvA) undergoing ConvA during the same period. The 2 co-primary outcomes were recurrence of arrhythmias and long-term complications. A total of 618 patients (mean age 38 ± 15 years, 60% female) were enrolled. MFA included 206 patients, whereas 412 were treated with ConvA. Acute success (99% vs. 97%; p=0.10) and acute complications (2.4% vs. 5.3%; p=0.14) were similar in the 2 groups. During a median follow-up of 4.4 years, 5.9% of patients experienced recurrence of arrhythmias. At multivariate analysis, ConvA (hazard ratio [HR]: 3.03) and procedural success (HR: 0.10) were independently associated with recurrence of arrhythmias. Late complications (i.e., advance atrioventricular block and need for pacemaker implantation) occurred more frequently in ConvA (3.4% vs. 0.5%; p=0.03) compared with MFA. CA guided by EAM systems with MFA provided better long-term results and reduced risk of complications compared with ConvA.