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The superior vena cava (SVC) is well described as one of the most common non-pulmonary vein (PV)-triggers for atrial tachyarrhythmias (ATA). In our study we evaluated a standardized approach for electrical isolation of the SVC from the right atrium using a horseshoe-shaped lesion set with optimized and contiguous ostial RF lesions. The results are promising, demonstrating a very high rate of acute SVC isolation in a safe and time efficient manner (mostly less than 10 min).

INTRODUCTION During left bundle branch area pacing (LBBAP) lead implantation, intermittent monitoring of unipolar pacing characteristics confirms LBB capture and can detect septal perforation. We aimed to demonstrate that continuous uninterrupted unipolar pacing from an inserted lead stylet (LS) is feasible and facilitates LBBAP implantation. METHODS Thirty patients (mean age 76 ± 14 years) were implanted with a stylet-driven pacing lead (Biotronik Solia S60). In 10 patients (comparison-group) conventional implantation with interrupted unipolar pacing was performed, with comparison of unipolar pacing characteristics between LS and connector-pin (CP)-pacing after each rotation step. In 20 patients (uninterrupted-group) performance and safety of uninterrupted implantation during continuous pacing from the LS were evaluated. RESULTS In the comparison-group, LS and CP-pacing impedances were highly correlated (R2 =0.95, p

Case description : A 74-year-old man suffering from severe heart failure (NYHA III – LVEF 28%) associated with left bundle branch block (LBBB) (Figure 1(A)) and uncontrolled permanent atrial fibrillation (AF) despite optimal medical treatment was referred for His ablation and rescue physiological pacing after a first unsuccessful LV lead implantation through the coronary sinus (CS). Careful review of the occluded CS angiogram indeed revealed no side branches. Concordantly, the patient was offered a ‘rescue’ HBP procedure. Using the SelectSecure lead (model 3830) and a C315 His sheath (Both Medtronic, Inc. MN), His mapping (HV ¼ 106ms) and recruitment were easily obtained, unfortunately without LBBB correction.

The QDOT Micro™ catheter (Biosense Webster, Inc., CA, USA) is a new radiofrequency ablation catheter based on the SmartTouch SF™ (Biosense Webster, Inc.). It combines diffuse external irrigation with six thermocouples located within the outer metal shell and three additional microelectrodes in a 3.5 mm-tip contact force radiofrequency catheter. This article focuses on the different characteristics of the catheter, which incorporates the ability of high power delivery, irrigation flow control based on temperature sensing through the six thermocouples and the generation of microelectrograms. An outline of its performance in preclinical and clinical setting is presented, showing promising results, especially concerning procedural efficiency and short-term safety. Additional studies need to confirm long-term effectiveness, and durability studies should evaluate whether superiority on a lesion quality level can be achieved.Lay abstract Radiofrequency (RF) energy is the most widely used type of energy in the field of catheter ablation, an invasive treatment for heart rhythm disorders. In patients with atrial fibrillation (AF; the most frequent type of problem with the rhythm of the heart), catheter ablation aims at delivering RF energy around the pulmonary veins (PVs). PVs have been shown to contain AF triggers. Catheter ablation results in electrical isolation of the PV, making them less likely to trigger AF. The latest technical developments resulted in better success rate of the procedure (up to 90% success rate after 1 year follow-up) without increasing complication rates. During the last decade, the catheter used to isolate the PV has improved a lot and includes now contact force measurement in addition to the delivery mechanism for RF energy and can record the local electrical activity. The newly developed QDOT Micro™ catheter (Biosense Webster, Inc., CA, USA), presented in this article, combines different aspects of further technical development. These include the integration of smaller electrodes, resulting in higher local electrical signal resolution, more accurate feedback of local tissue temperature during the procedure and the ability to use higher RF power which reduces the RF delivery time and therefore reduced the duration of the procedure. An outline of its performance in preclinical and clinical setting is presented in this paper. These studies have shown promising results, especially concerning procedural efficiency and short-term safety. However, additional studies need to confirm long-term treatment success and potential superiority in comparison with other ablation approaches.

Conventional stylet-driven leads with extendable helix can be implanted successfully for Left Bundle Branch Area Pacing (LBBAP) with a low acute complication rate. However, removal and repositioning techniques of these leads haven’t been yet described. We report 2 cases in which lead repositioning after a first unsuccessful attempt to LBBAP was associated with fracture of the helix rotating mechanism and failure to fully extract the pacing lead.

Background: CLOSE-guided atrial fibrillation (AF) ablation is based on contiguous (intertag distance ≤6 mm), optimized (Ablation Index >550 anteriorly and >400 posteriorly) point-by-point radiofrequency lesions. The optimal radiofrequency power remains unknown. Methods: The POWER-AF study is a prospective, randomized controlled monocentric study including patients with paroxysmal AF, planned for first CLOSE-guided pulmonary vein isolation using a contact force radiofrequency catheter (Thermocool SmartTouch, Biosense Webster, Inc, Irvine, CA). A total of 100 patients were randomized into 2 groups (1:1). The control group received AF ablation using the standard CLOSE protocol (35 W), whereas in the experimental group, pulmonary vein isolation was performed using high power (45 W). Endoscopic evaluation was performed in patients with intraesophageal temperature rise >38.5 °C. Results: The resulting sample size was 96 (48+48) patients. In the high power group, shorter procedure time (80 versus 102 minutes, P P P P P =0.31) showed an ulcerative perforation in a high power group patient (treated by endoscopic stenting and normalization after ≈4 months) and a superficial ulcerative lesion in a control group patient (conservative treatment). Both occurred following excessive Ablation Index applications (up to 460 and 480, respectively) with excessive contact force (30 g on average, with peaks up to 50 g). Six-months AF recurrence was not significantly different (10% in high power versus 8% in control, P =0.74). Conclusions: This randomized controlled study shows that a 45 W radiofrequency power CLOSE protocol in patients with paroxysmal AF significantly increases the global procedural efficiency with similar midterm efficacy. However, our study showed a narrower safety margin and a limited increased efficiency at the posterior wall using high power. This advocates against the use of high power in the region neighboring the esophagus.

The aim of this study was to analyze the feasibility and reproducibility of using image integration software at a remote setting over the MUSIC network to perform image-guided VT ablation. Furthermore, we analyzed the efficacy of a focused workflow with electroanatomical mapping (EAM) limited to imaging-defined scar. In a prospective two-centre study, consecutive patients undergoing image integration-guided VT ablation (magnetic resonance [DE-MRI] and/or multidetector computed tomography [MDCT]) were included. Patients were divided into two groups (Group 1, complete EAM; Group 2, EAM limited to imaging-defined substrate). Forty-nine patients (62 ± 15 years; 90% male; LVEF 41 ± 14%; ischemic 69%) who underwent image integration-guided VT ablation were included (MDCT 98%; DE-MRI in 35%). Total procedure time was 172 ± 48 min (ablation 31 ± 17 min; fluoroscopy 23 ± 13 min). Procedure time was shorter in Group 2 as compared to Group 1 (Group 2 [n = 26] vs. Group 1 [n = 23]; procedure time: 151 ± 33 vs. 180 ± 53 min, P = 0.01). Non-inducibility of all VT was achieved in 37 (76%), with no difference between Group 1 and 2 (Group 2 vs. Group 1; VT non-inducibility 71 vs. 74%, P = 0.8). During a follow-up period of 19 ± 8 months, 13 patients (27%) had a VT recurrence. Two patients (4%) died during follow-up. There were no differences in VT-free survival between Group 1 and Group 2 (p = 0.77). Image-integrated VT ablation is feasible through a network between highly experienced centers and remotely located centers. Focused image integration-guided VT ablation is associated with short and predictable procedure duration, achieving high-long term success rates.

Aims Catheter ablation of paroxysmal atrial fibrillation (AF) reduces AF recurrence, AF burden, and improves quality of life. Data on clinical and procedural predictors of arrhythmia recurrence are scarce and are flawed by the high rate of pulmonary vein reconnection evidenced during repeat procedures after pulmonary vein isolation (PVI). In this study, we identified clinical and procedural predictors for AF recurrence 1 year after CLOSE-guided PVI, as this strategy has been associated with an increased PVI durability. Methods and results Patients with paroxysmal AF, who received CLOSE-guided PVI and who participated in a prospective trial in our centre, were included in this study. Uni- and multivariate models were plotted to find clinical and procedural predictors for AF recurrence within 1 year. Three hundred twenty-five patients with a mean age of 63 years (CHA2DS2VASc 1 [1–3], left atrium diameter 41 ± 6 mm) were included. About 60.9% were male individuals. After 1 year, AF recurrence occurred in 10.5% of patients. In a binary logistic regression analysis, the diagnosis-to-ablation time (DAT) was found to be the strongest predictor of AF recurrence (P = 0.011). Diagnosis-to-ablation time ≥1 year was associated with a nearly two-fold increased risk for developing AF recurrence. Conclusion The DAT is the most important predictor of arrhythmia recurrence in low-risk patients treated with durable pulmonary vein isolation for paroxysmal AF. Whether reducing the DAT could improve long-term outcomes should be investigated in another trial.

Aims: “CLOSE”-guided pulmonary vein isolation (PVI) is based on contiguous (≤6 mm) and optimized radiofrequency (RF) ablation lesions (ablation index [AI] ≥ 400 posteriorly and ≥ 550 anteriorly]. However, the optimal RF power to reach the desired AI is unknown. Therefore we evaluated the efficiency of an ablation strategy using higher power (40 W) during a first “CLOSE”-guided PVI. Methods: Eighty consecutive patients undergoing “CLOSE”-guided PVI for symptomatic paroxysmal atrial fibrillation were ablated with 40 W (group A). Results were compared with 105 consecutive patients enrolled in the “CLOSE to CURE”-study and were ablated using the same protocol with 35 W (group B). Results: In group A, ablation was associated with shorter ablation procedure time (91 vs 111 minutes; P .733) were similar in both groups (groups A and B, respectively). No complications occurred. In group A, a gastroscopy—performed in five patients with esophageal temperature rise more than 42°C—did not reveal any esophageal lesion. Postprocedural recurrence of atrial tachyarrhythmia at 1 year was not significantly different between both groups. Conclusions: Using the “CLOSE”-protocol, increased power increases the efficiency of PVI without compromising patients' safety., SCOPUS: ar.j, info:eu-repo/semantics/published

AIM: To evaluate the prognostic value of electrophysiological stimulation (EPS) in the risk stratification for tachyarrhythmic events and sudden cardiac death (SCD). METHODS: We conducted a prospective cohort study and analyzed the long-term follow-up of 265 consecutive patients who underwent programmed ventricular stimulation at the Luzerner Kantonsspital (Lucerne, Switzerland) between October 2003 and April 2012. Patients underwent EPS for SCD risk evaluation because of structural or functional heart disease and/or electrical conduction abnormality and/or after syncope/cardiac arrest. EPS was considered abnormal, if a sustained ventricular tachycardia (VT) was inducible. The primary endpoint of the study was SCD or, in implanted patients, adequate ICD-activation. RESULTS: During EPS, sustained VT was induced in 125 patients (47.2%) and non-sustained VT in 60 patients (22.6%); in 80 patients (30.2%) no arrhythmia could be induced. In our cohort, 153 patients (57.7%) underwent ICD implantation after the EPS. During follow-up (mean duration 4.8 ± 2.3 years), a primary endpoint event occurred in 49 patients (18.5%). The area under the receiver operating characteristic curve (AUROC) was 0.593 (95%CI: 0.515-0.670) for a left ventricular ejection fraction (LVEF) < 35% and 0.636 (95%CI: 0.563-0.709) for inducible sustained VT during EPS. The AUROC of EPS was higher in the subgroup of patients with LVEF ≥ 35% (0.681, 95%CI: 0.578-0.785). Cox regression analysis showed that both, sustained VT during EPS (HR: 2.26, 95%CI: 1.22-4.19, P = 0.009) and LVEF < 35% (HR: 2.00, 95%CI: 1.13-3.54, P = 0.018) were independent predictors of primary endpoint events. CONCLUSION: EPS provides a benefit in risk stratification for future tachyarrhythmic events and SCD and should especially be considered in patients with LVEF ≥ 35%.