Complexities of treating co-morbidities in heart failure with preserved ejection fraction.

Atrial fibrillation and heart failure with preserved ejection fraction (HFpEF) are frequent concomitant diseases sharing several pathophysiological mechanisms leading to structural remodelling of both atria and ventricles. We present a case of an HFpEF patient with rapid atrial fibrillation who remained symptomatic even after successful cardioversion, initiation of antiarrhythmic therapy, and treatment of comorbidities. Due to asymmetric septal hypertrophy, the stress test was performed to exclude outflow tract obstruction and revealed a low basal heart rate with significant chronotropic insufficiency. In addition to SGLT2 initiation, the beta-blocker dose was reduced, and amiodarone was discontinued. This therapy modification led to a marked improvement in exercise capacity, significant reduction of palpitations, reduction of NT-proBNP, and signs of a decreased left ventricular filling pressure with reverse remodelling of LA. This case shows the importance of both individual tailoring of medical therapy and chronotropic insufficiency in HFpEF patients.

Impact of preventive substrate catheter ablation on implantable cardioverter-defibrillator interventions in patients with ischaemic cardiomyopathy and infarct-related coronary chronic total occlusion.

AIMS: Primary prevention patients with ischaemic cardiomyopathy and chronic total occlusion of an infarct-related coronary artery (CTO) are at a particularly high risk of implantable cardioverter-defibrillator (ICD) therapy occurrence. The trial was designed to evaluate the efficacy of preventive CTO-related substrate ablation strategy in ischaemic cardiomyopathy patients undergoing primary prevention ICD implantation. METHODS AND RESULTS: The PREVENTIVE VT study was a prospective, multicentre, randomized trial including ischaemic patients with ejection fraction ≤40%, no documented ventricular arrhythmias (VAs), and evidence of scar related to the coronary CTO. Patients were randomly assigned 1:1 to a preventive substrate ablation before ICD implantation or standard therapy with ICD implantation only. The primary outcome was a composite of appropriate ICD therapy or unplanned hospitalization for VAs. Secondary outcomes included the primary outcome's components, the incidence of appropriate ICD therapies, cardiac hospitalization, electrical storm, and cardiovascular (CV) mortality. Sixty patients were included in the study. During the mean follow-up of 44.7 ± 20.7 months, the primary outcome occurred in 5 (16.7%) patients undergoing preventive substrate ablation and in 13 (43.3%) patients receiving only ICD [hazard ratio (HR): 0.33; 95% confidence interval (CI): 0.12-0.94; P = 0.037]. Patients in the preventive ablation group also had fewer appropriate ICD therapies (P = 0.039) and the electrical storms (Log-rank: P = 0.01). While preventive ablation also reduced cardiac hospitalizations (P = 0.006), it had no significant impact on CV mortality (P = 0.151). CONCLUSION: Preventive ablation of the coronary CTO-related substrate in patients undergoing primary ICD implantation is associated with the reduced risk of appropriate ICD therapy or unplanned hospitalization due to VAs.

AV-optimized conduction system pacing for treatment of AV dromotropathy: A randomized, cross-over study.

BACKGROUND: Severe first-degree atrioventricular (AV) block may produce symptoms similar to heart failure due to AV dyssynchrony, a syndrome termed AV dromotropathy. According to guidelines, it should be considered for permanent pacemaker implantation, yet evidence supporting this treatment is scarce. OBJECTIVES: This study aimed to determine the impact of AV-optimized conduction system pacing (CSP) in patients with symptomatic severe first-degree AV block and echocardiographic signs of AV dyssynchrony. METHODS: Patients with symptomatic first-degree AV block (PR > 250 ms), preserved left ventricular ejection fraction, narrow QRS, and AV dyssynchrony were included in the study. In a single-blind cross-over design, patients were randomized to AV sequential CSP or backup VVI pacing with a base rate of 40 bpm. We compared exercise capacity, echocardiographic parameters, and symptom occurrence at the end of 3 months of each period. RESULTS: Fourteen patients completed the study. During the AV-optimized CSP compared to the backup pacing period, patients achieved a higher workload on exercise test (147.2 ± 50.9 vs. 140.7 ± 55.8 W; p = .032), with a trend towards higher peak VO2 (23.3 ± 7.1 vs. 22.8 ± 7.1 mL/min/kg; p = .224), and higher left ventricular stroke volume (LVSV 74.5 ± 13.8 vs. 66.4 ± 12.5 mL; p < .001). Symptomatic improvement was recorded, with fewer patients reporting general tiredness and 71% of patients preferring the AV-optimized CSP (p = .008). CONCLUSIONS: AV-optimized CSP could improve symptoms, exercise capacity and LVSV in patients with severe first-degree AV block.

Zero-Fluoroscopy Catheter Ablation of Supraventricular Tachycardias in the Pediatric Population.

Catheter ablation (CA) of supraventricular tachycardias (SVTs) is conventionally performed with the aid of X-ray fluoroscopy. Usage of a three-dimensional (3D) electro-anatomical mapping (EAM) system and intracardiac echocardiography (ICE) enables zero-fluoroscopy ablation, eliminating the harmful effects of radiation. We retrospectively analyzed the feasibility, effectiveness and safety of zero-fluoroscopy radiofrequency and cryoablation of various types of SVTs in pediatric patients. Overall, in 171 consecutive patients (12.5 ± 3.9 years), 175 SVTs were diagnosed and 201 procedures were performed. The procedural success rate was 98% (193/197), or more precisely, 100% (86/86) for AVNRT, 95.8% (91/95) for AVRT, 94.1% (16/17) for AT and 100% (2/2) for AFL. No complications were recorded. Follow-up was complete in 100% (171/171) of patients. During the mean follow-up period of 488.4 ± 409.5 days, 98.2% of patients were arrhythmia-free with long-term success rates of 98.7% (78/79), 97.5% (78/80), 100% (13/13) and 100% (2/2) for AVNRT, AVRT, AT and AFL, respectively. Zero-fluoroscopy CA of various types of SVTs in the pediatric population is a feasible, effective and safe treatment option.

Case report: A complex case of valve-in-valve TAVI and left bundle branch pacing for severe aortic regurgitation with partially corrected type A aortic dissection and low ejection fraction.

Background: Aortic regurgitation is a major concern following transcatheter aortic valve implantation (TAVI), as even low-grade regurgitation is associated with increased mortality. This is of particular concern to patients with pre-existing aortic disease who are at increased risk of TAVI valve slippage. Furthermore, conduction system disturbances after TAVI, namely left bundle branch block (LBBB), may have an additional detrimental effect on cardiac function. Case presentation: This report documents a successful treatment strategy in a frail patient with a bicuspid aortic valve and aortic disease after valve-sparing surgical repair in 1998, who subsequently developed aortic stenosis and underwent TAVI with an Evolut R self-expanding aortic valve. The progression of aortic disease, aortic root dilatation, and leaflet degeneration over the following years caused aortic regurgitation of the self-expanding aortic valve, resulting in left ventricular dilatation and heart failure along with LBBB and left ventricular (LV) mechanical dyssynchrony. Diagnostic workup of the patient showed persistence of the aneurysm distal to the graft with a dissection spanning the ascending aorta, arch, and terminating proximal to the aortic isthmus. After consideration by the cardiac team, a balloon-expandable valve was chosen for a valve-in-valve (ViV) procedure to provide sufficient radial force to expand the existing valve and correct the regurgitation. Due to the anatomy, a J-wire and pigtail catheter were successfully used for a safe approach and placement of the valve. Following the procedure, intermittent complete atrioventricular block was observed in addition to the pre-existing left bundle branch block, necessitating resynchronization pacing. Due to anatomical considerations, ease of placement, and the expected good level of resynchronization due to the proximal block, we opted for left bundle branch pacing, which showed improvement in left ventricular dyssynchrony and LV function at follow-up. Conclusion: Valve-in-valve implantation of a balloon-expandable Myval TAVI device to treat aortic regurgitation caused by slippage and right leaflet disfunction of slef valve is feasible in challenging anatomical scenarios. Left bundle branch pacing is a viable alternative to correct mechanical dyssynchrony in complex patients with LBBB and anatomical challenges necessitating resynchronization.

Effect of Coronary Sinus Reducer Implantation on Aerobic Exercise Capacity in Refractory Angina Patients-A CROSSROAD Study.

Coronary sinus reducer (CSR) implantation is a new treatment option for patients with refractory angina pectoris. However, there is no evidence from a randomized trial that would show an improvement in exercise capacity after this treatment. The aim of this study was to evaluate the influence of CSR treatment on maximal oxygen consumption and compare it to a sham procedure. Twenty-five patients with refractory angina pectoris (Canadian Cardiovascular Society (CCS) class II-IV) were randomized to a CSR implantation (n = 13) or a sham procedure (n = 12). At baseline and after 6 months of follow-up, the patients underwent symptom-limited cardiopulmonary exercise testing with an adjusted ramp protocol and assessment of angina pectoris using the CCS scale and Seattle angina pectoris questionnaire (SAQ). In the CSR group, maximal oxygen consumption increased from 15.56 ± 4.05 to 18.4 ± 5.2 mL/kg/min (p = 0.03) but did not change in the sham group (p = 0.53); p for intergroup comparison was 0.03. In contrast, there was no difference in the improvement of the CCS class or SAQ domains. To conclude, in patients with refractory angina and optimized medical therapy, CSR implantation may improve oxygen consumption beyond that of optimal medical therapy.

Conversion to Sinus Rhythm in Refractory Atrial Fibrillation Patients after Atrioventricular Node Ablation with Conduction System Pacing.

Background: "Ablate and pace" strategy is a reasonable treatment option in refractory atrial fibrillation (AF) when sinus rhythm (SR) cannot be achieved with catheter ablation or pharmacological therapy. Atrioventricular node ablation (AVNA) combined with conduction system pacing (CSP), with left bundle branch pacing (LBBP) or His bundle pacing (HBP), is gaining recognition since it offers the most physiological activation of the left ventricle. However, the incidence of conversion to SR after AVNA with CSP is not known. The purpose of the investigation was to determine the incidence of spontaneous conversion to SR and its predicting factors in patients undergoing CSP and AVNA. Methods: Consecutive refractory symptomatic AF patients undergoing AVNA with CSP at our institution between June 2018 and December 2022 were retrospectively analyzed. Twelve lead electrocardiogram (ECG) recordings were analyzed at each outpatient follow-up visit. Echocardiographic and clinical parameters were assessed at baseline and six months after the implantation. Results: Sixty-eight patients (male 42.6%, age 71 ± 8 years, left ventricular ejection fraction 40 ± 15%) were included. Thirty-seven patients (54.4%) received HBP and 31 (45.6%) LBBP. During follow-up, spontaneous conversion to SR was registered in 6 patients (8.8%); 3 in the HBP group and 3 in the LBBP group. Baseline characteristics of patients who converted to SR did not differ from non-sinus rhythm (NSR) patients except for left atrial volume index (LAVI), which was significantly smaller in the SR group (45 mL/ m 2 (41-51) vs. 60 mL/ m 2 (52-75); p = 0.002). Multiple regression model confirmed an inverse association between LAVI and conversion to SR even after considering other clinically relevant covariates (odds ratio 1.273, p = 0.028). At follow-up, LAVI did not change in any group (SR: p = 0.345; NSR: p = 0.508). Improvement in New York Heart Association (NYHA) class was comparable in both groups. Conclusions: Spontaneous conversion to SR after AVNA combined with CSP is not uncommon, especially in patients with smaller left atria. Further studies are warranted to clarify which patients should be considered for initial dual-chamber device implantation to provide atrio-ventricular synchrony in case of SR restoration.

The Impact of Coronary Sinus Reducer on Arrhythmic Properties in Patients with Refractory Angina.

Background: Treatment with a coronary sinus reducer (CSR) is a new therapeutic option for refractory angina patients. Preclinical studies have shown antiarrhythmic properties of coronary sinus narrowing. The possible antiarrhythmic effect of CSR implantation is unknown. This study aimed to determine the possible antiarrhythmic effects of CSR implantation as assessed by high-resolution electrocardiogram (hrECG) parameters. Methods: 24 patients from the Crossroad study randomized to either CSR treatment (n = 12) or a sham procedure (n = 12) had hrECG recorded at baseline and after 6 months. T-peak and T-end interval (TpTe) defined as the time difference between the peak amplitude of the T wave and the global end of the T wave, spatial angle between QRS complex and T axis defined as the angle between the ventricular depolarization and repolarization vectors using maximal (QRSTP) and mean (QRSTM) vector amplitudes and spatial ventricular gradient (SVG) calculated as integral of ECG voltages over the entire QRST complex were analyzed. Additionally, we analyzed parameters of QT and heart rate variability using time and frequency domain. Results: At baseline, all analyzed parameters were comparable between both groups and heart rate remained constant. The intragroup analysis did not show any significant change in TpTe, QRSTP, QRSTM, SVG, QT, and heart rate variability at follow-up. Furthermore, intergroup comparison between CSR implantation and sham procedure also did not show any significant difference in the change of analyzed parameters. Conclusions: Compared to the sham procedure, CSR implantation did not demonstrate a significant impact on the arrhythmogenic substrate assessed with hrECG. Clinical Trial Registration: Unique Identifier: NCT04121845, https://classic.clinicaltrials.gov/ct2/show/NCT04121845.

Case report: Treatment of tachycardia-induced cardiogenic shock with permanent His bundle pacing and atrioventricular node ablation.

Tachycardia-induced cardiomyopathy (T-CMP) related to supraventricular arrhythmia is a rare and often unrecognized cause of refractory cardiogenic shock. When rhythm control interventions are ineffective or no longer pursued, atrioventricular node ablation (AVNA) with pacemaker implantation is indicated. Conduction system pacing provides normal synchronous activation of the ventricles after AVNA. However, there is a lack of data on pace and ablate strategy in hemodynamically unstable patients. We report on 2 patients with T-CMP presenting with refractory cardiogenic shock who were successfully treated with His bundle pacing in conjunction with AVNA.

Right-sided approach to left bundle branch area pacing combined with atrioventricular node ablation in a patient with persistent left superior vena cava and left bundle branch block: a case report.

BACKGROUND: Left bundle branch area pacing (LBBAP) is an alternative to right ventricular (RV) and biventricular (BiV) pacing in patients scheduled for pace and ablate treatment strategy. However, current delivery sheaths are designed for left-sided implantation, making the right-sided LBBAP lead implantation challenging. CASE PRESENTATION: We report a case of a right-sided LBBAP approach via right subclavian vein in a heart failure patient with a persistent left superior vena cava scheduled for pace and ablate treatment of refractory atrial flutter. To enable adequate lead positioning and support for transseptal screwing, the delivery sheath was manually modified with a 90-degree curve at the right subclavian vein and superior vena cava junction to allow right-sided implantation. The distance between the reshaping point and the presumed septal region was estimated by placing the sheath on the body surface under fluoroscopy. With the reshaping of the delivery sheath, we were able to achieve LBBAP with relatively minimal torque. Radiofrequency ablation of the atrioventricular node was performed the next day and the pacing parameters remained stable in short-term follow-up. CONCLUSION: With the modification of currently available tools, LBBAP can be performed with the right-sided approach.

Biventricular versus Conduction System Pacing after Atrioventricular Node Ablation in Heart Failure Patients with Atrial Fibrillation.

Conduction system pacing (CSP) modalities, including His-bundle pacing (HBP) and left bundle branch pacing (LBBP), are increasingly used as alternatives to biventricular (BiV) pacing in heart failure (HF) patients scheduled for pace and ablate strategy. The aim of the study was to compare clinical outcomes of HF patients with refractory AF who received either BiV pacing or CSP in conjunction with atrio-ventricular node ablation (AVNA). Fifty consecutive patients (male 48%, age 70 years (IQR 9), left ventricular ejection fraction (LVEF) 39% (IQR 12)) were retrospectively analysed. Thirteen patients (26%) received BiV pacing, 27 patients (54%) HBP and 10 patients (20%) LBBP. All groups had similar baseline characteristics and acute success rate. While New York Heart. Association (NYHA) class improved in both HBP (p < 0.001) and LBBP (p = 0.008), it did not improve in BiV group (p = 0.096). At follow-up, LVEF increased in HBP (form 39% (IQR 15) to 49% (IQR 16), p < 0.001) and LBBP (from 28% (IQR 13) to 40% (IQR 13), p = 0.041), but did not change in BiV group (p = 0.916). Conduction system pacing modalities showed superior symptomatic and echocardiographic improvement compared to BiV pacing after AVNA. With more stable pacing parameters, LBBP could present a more feasible pacing option compared to HBP.

Conventional fluoroscopy-guided versus zero-fluoroscopy catheter ablation of supraventricular tachycardias.

PURPOSE: The aim of this study was to evaluate the safety and efficacy of zero-fluoroscopy (ZF) catheter ablation (CA) for supraventricular tachycardias (SVT). METHODS: 584 consecutive patients referred to our institution for CA of SVT were analysed. Patients were categorised into two groups; zero-fluoroscopy (ZF) group and conventional fluoroscopy (CF) group. The ZF group was further divided into two subgroups (adults and paediatric). Patient characteristics, procedural information, and follow-up data were compared. RESULTS: The ZF group had a higher proportion of paediatric patients (42.2% vs 0.0%; p < 0.001), resulting in a younger age (30.9 ± 20.3 years vs 52.7 ± 16.5 years; p < 0.001) and lower BMI (22.8 ± 5.7 kg/m2 vs 27.0 ± 5.4 kg/m2; p < 0.001). Procedure time was shorter in the ZF group (94.2 ± 50.4 min vs 104.0 ± 54.0 min; p = 0.002). There were no major complications and the rate of minor complications did not differ between groups (0.0% vs 0.4%; p = 0.304). Acute procedural success as well as the long-term success rate when only the index procedure was considered did not differ between groups (92.5% vs 95.4%; p = 0.155; 87.1% vs 89.2%; p = 0.422). When repeated procedures were included, the long-term success rate was higher in the ZF group (98.3% vs 93.5%; p = 0.004). The difference can be partially explained by the operators' preferences. CONCLUSION: The safety and efficacy of ZF procedures in adult and paediatric populations are comparable to that of CF procedures.

Efficacy of coronary sinus reducer implantation in patients with chronic total occlusion of the right coronary artery.

BACKGROUND: Clinical efficacy of coronary sinus reducer (CSR) in refractory angina (RA) patients with ischemia due to the chronic total occlusion (CTO) of the right coronary artery (RCA) remains unknown. AIMS: To evaluate the efficacy of CSR implantation in RA patients with CTO RCA and compare them to CSR recipients with left coronary artery (LCA) ischemia. METHODS: Consecutive patients with CTO RCA from 2 centers were prospectively included and compared to patients with LCA ischemia. All patients underwent evaluation of angina severity and quality of life (QoL) at baseline and after 12 months. In a subgroup of CTO RCA patients, stress cardiac magnetic resonance (CMR) imaging was also performed. RESULTS: Twenty-two patients with CTO RCA and predominant inferior and/or inferoseptal wall ischemia (the CTO RCA group) were compared to 24 patients with predominant anterior, lateral, and/or anteroseptal wall ischemia (the LCA group). While the Canadian Cardiovascular Society (CCS) anginascore mean (SD) improved in the CTO RCA group from 2.73 (0.46) to 1.82 (0.73) (P <0.001) and in the LCA group from 2.67 (0.57) to 1.92 (0.72) (P <0.001), there was no intergroup difference (P = 0.350). Significant improvement in all domains of the Seattle Angina Questionnaire was observed. Stress CMR did not show a significant reduction of ischemic inferior and/or inferoseptal segments, however, improvements in the transmurality index (P = 0.03) and the myocardial perfusion reserve index in segments with inducible ischemia (P = 0.03) were observed in the CTO RCA group. CONCLUSIONS: In CTO RCA patients, CSR implantation alleviated angina symptoms and improved QoL. The extent of improvement was comparable to that observed in patients with LCA ischemia.

Biventricular versus His bundle pacing after atrioventricular node ablation in heart failure patients with narrow QRS.

Background: His bundle pacing (HBP) is a physiological alternative to biventricular (BiV) pacing. We compared short-term results of both pacing approaches in symptomatic atrial fibrillation (AF) patients with moderately reduced left ventricular (LV) ejection fraction (EF ≥35% and <50%) and narrow QRS (≤120 ms) who underwent atrioventricular node ablation (AVNA).Methods: Thirty consecutive AF patients who received BiV pacing or HBP in conjunction with AVNA between May 2015 and January 2020 were retrospectively assessed. Electrocardiographic, echocardiographic, and clinical data at baseline and 6 months after the procedure were assessed.Results: Twenty-four patients (age 68.8 ± 6.5 years, 50% female, EF 39.6 ± 4%, QRS 95 ± 10 ms) met the inclusion criteria, 12 received BiV pacing and 12 HBP. Both groups had similar acute procedure-related success and complication rates. HBP was superior to BiV pacing in terms of post-implant QRS duration, implantation fluoroscopy times, reduction of indexed LV volumes (EDVi 63.8 (49.6-81) mL/m2 vs. 79.9 (66-100) mL/m2, p = 0.055; ESVi 32.7 (25.6-42.6) mL/m2 vs. 46.4 (42.9-68.1) mL/m2, p = 0.009) and increase in LVEF (46 (41-55) % vs. 38 (35-42) %, p = 0.005). However, the improvement of the NYHA class was similar in both groups.Conclusions: In symptomatic AF patients with moderately reduced EF and narrow QRS undergoing AVNA, HBP could be a conceivable alternative to BiV pacing. Further prospective studies are warranted to address the outcomes between both 'ablate and pace' strategies.

Integrated 3D intracardiac ultrasound imaging with detailed pulmonary vein delineation guided fluoroless ablation of atrial fibrillation.

BACKGROUND: Intracardiac echocardiography (ICE) has become an all-round tool for ablation of atrial fibrillation (AF) since it plays an important role in all procedural steps. The key upgrade to the usefulness of ICE is its integration into three-dimensional (3D) electroanatomic mapping (EAM) system (ICE/EAM automatic integration system). The aim of this single-center retrospective study was to evaluate feasibility, safety and acute efficacy of ICE/EAM automatic integration system guided fluoroless ablation of AF. METHODS: The study included patients with symptomatic paroxysmal or persistent AF undergoing first pulmonary vein isolation (PVI) radiofrequency (RF) catheter ablation (RFCA) from September 2017 to August 2020. All procedures were performed without the use of fluoroscopy. A detailed 3D virtual anatomy of the left atrium (LA) and structures relevant to AF ablation was constructed from ultrasound contours obtained with ICE probe inside the LA. Pulmonary veins (PVs) and antral regions were additionally mapped with fast anatomical mapping (FAM). PVI was performed with contact force (CF) sensing catheter. Procedural endpoint was successful PVI. RESULTS: A total of 98 consecutive patients underwent RFCA (34.7% females, median age 64.4 years, 64.3% paroxysmal AF). Acute PVI was achieved in all patients (100%). Forty-three patients (43.9%) underwent additional ablations for concomitant arrhythmias. Adverse events were detected in four patients (4.1%). The median procedure duration was 130 min (IQR 103.8-151.3). If only PVI was done the median procedure duration was 110.5 (IQR 100.0-133.8) CONCLUSIONS: ICE/EAM automatic integration system guided fluoroless ablation of AF is feasible, safe and acutely effective method for treatment of symptomatic AF.

Minimising radiation exposure in catheter ablation of ventricular arrhythmias.

BACKGROUND: Conventional fluoroscopy guided catheter ablation (CA) is an established treatment option for ventricular arrhythmias (VAs). However, with the complex nature of most procedures, patients and staff bare an increased radiation exposure. Near-zero or zero-fluoroscopy CA is an alternative method which could substantially reduce or even eliminate the radiation dose. Our aim was to analyse procedural outcomes with fluoroscopy minimising approach for treatment of VAs in patients with structurally normal hearts (SNH) and structural heart disease (SHD). METHODS: Fifty-two (age 53.4 ± 17.8 years, 38 male, 14 female) consecutive patients who underwent CA of VAs in our institution between May 2018 and December 2019 were included. Procedures were performed primarily with the aid of the three-dimensional electro-anatomical mapping system and intra-cardiac echocardiography. Fluoroscopy was considered only in left ventricular (LV) summit mapping for coronary angiography and when epicardial approach was planned. Acute and long-term procedural outcomes were analysed. RESULTS: Sixty CA procedures were performed. Twenty-five patients had SHD-related VAs (Group 1) and 27 patients had SNH (Group 2). While Group 1 had significantly higher total procedural time (256.9 ± 71.7 vs 123.6 ± 42.2 min; p < 0.001) compared to Group 2, overall procedural success rate [77.4% (24/31) vs 89.7% (26/29); p = 0.20)] and recurrence rate after the first procedure [8/25, (32%) vs 8/27, (29.6%); p = 0.85] were similar in both groups. Fluoroscopy was used in 3 procedures in Group 1 where epicardial approach was needed and in 4 procedures in Group 2 where LV summit VAs were ablated. Overall procedure-related major complication rate was 5%. CONCLUSIONS: Fluoroscopy minimising approach for CA of VAs is feasible and safe in patients with SHD and SNH. Fluoroscopy could not be completely abolished in VAs with epicardial and LV summit substrate location.

Fluoroless catheter ablation of accessory pathways in adult and pediatric patients: a single centre experience.

Catheter radio-frequency ablation (RFA) and cryo-ablation (CRA) procedures are an effective and safe treatment options for adult and pediatric patients with accessory pathway (AP) mediated tachycardias. Non-fluoroscopic techniques during catheter ablation (CA) procedures reduce potentially harmful effects of radiation. Our aim was to investigate the efficacy and safety of completely fluoroless RFA and CRA procedures in pediatric and adult patients with APs. Consecutive patients with AP-related tachycardia and high risk asymptomatic ventricular pre-excitation were assessed in retrospective analysis. Three-dimensional (3D) electro-anatomical mapping (EAM) and intra-cardiac echocardiography (ICE) were used as principal imaging modalities. Fluoroscopy was not used during any stage of the procedures. Among 116 included patients (22.76 ± 16.1 years, 68 patients < 19 years), 60 had left-sided APs, 16 right-sided APs and 40 septal APs. Altogether, 96 had RFA and 20 CRA procedures. The acute success rates (ASR) of RFA and CRA were 97.9% and 95%, respectively (p = 0.43), with recurrence rates (RR) of 8.33% and 40%, respectively (p < 0.0001). The outcome difference was principally driven by lower RR with RFA in septal APs (9.1% vs. 38.9%, p = 0.025). Pediatric patients with APs (12.21 ± 3.76 years) had similar procedural parameters and outcomes compared to adult patients. There were no procedure-related complications. In adult and pediatric patients with AP-related tachycardias, both CRA and RFA can be effectively and safely performed without the use of fluoroscopy. In addition, RFA resulted in better outcomes compared to CRA.