[Rhythm management in patients with heart failure].

INTRODUCTION: Arrhythmias manifest frequently in individuals with heart failure, posing a notable threat of mortality and morbidity. While the prevention of sudden cardiac death through ICD therapy remains pivotal, accurate risk stratification remains a challenging task even in 2024. Recent data underscore the early consideration of catheter ablation for ventricular tachycardias. Although antiarrhythmic drug therapy serves as an ancillary measure for symptomatic patients, it does not confer prognostic advantages. The holistic management of arrhythmias in heart failure necessitates a systematic, multidimensional approach that initiates with evidence-based medical therapy for heart failure and integrates device-based and interventional therapies. Noteworthy clinical studies have illustrated the positive prognostic impact of early rhythm control strategies, particularly catheter ablation, in individuals managing heart failure and atrial fibrillation.

Dual energy for pulmonary vein isolation using dual-energy focal ablation technology integrated with a three-dimensional mapping system: SmartfIRE 3-month results.

AIMS: Contact force (CF)-sensing radiofrequency (RF) catheters with an ablation index have shown reproducible outcomes for the treatment of atrial fibrillation (AF) in large multicentre studies. A dual-energy (DE) focal CF catheter to deliver RF and unipolar/biphasic pulsed field ablation (PFA), integrated with a three-dimensional (3D) mapping system, can provide operators with additional flexibility. The SmartfIRE study assessed the safety and efficacy of this novel technology for the treatment of drug-refractory, symptomatic paroxysmal AF. Results at 3 months post-ablation are presented here. METHODS AND RESULTS: Pulmonary vein isolation (PVI) was performed using a DE focal, irrigated CF-sensing catheter with the recommendation of PFA at posterior/inferior and RF ablation at the anterior/ridge/carina segments. Irrespective of energy, a tag size of 3 mm; an inter-tag distance ≤6 mm; a target index of 550 for anterior, roof, ridge, and carina; and a target index of 400 for posterior and inferior were recommended. Cavotricuspid isthmus ablation was permitted in patients with documented typical atrial flutter. The primary effectiveness endpoint was acute procedural success. The primary safety endpoint was the rate of primary adverse events (PAEs) within 7 days of the procedure. A prespecified patient subset underwent oesophageal endoscopy (EE; 72 h post-procedure), neurological assessment (NA; pre-procedure and discharge), and cardiac computed tomography (CT)/magnetic resonance angiogram (MRA) imaging (pre-procedure and 3 months post-procedure) for additional safety evaluation, and a mandatory remapping procedure (Day 75 ± 15) for PVI durability assessment. Of 149 patients enrolled between February and June 2023, 140 had the study catheter inserted (safety analysis set) and 137 had ablation energy delivered (per-protocol analysis set). The median (Q1/Q3) total procedure and fluoroscopy times were 108.0 (91.0/126.0) and 4.2 (2.3/7.7) min (n = 137). The acute procedural success rate was 100%. First-pass isolation was achieved in 89.1% of patients and 96.8% of veins. Cavotricuspid isthmus ablations were successfully performed in 12 patients [pulsed field (PF) only: 6, RF only: 5, and RF/PF: 1]. The PAE rate was 4.4% [6/137 patients; 2 pulmonary vein (PV) stenoses, 2 cardiac tamponades/perforations, 1 stroke, and 1 pericarditis]. No coronary artery spasm was reported. No oesophageal lesion was seen in the EE subset (0/31, 0%). In the NA subset (n = 30), microemboli lesions were identified in 2 patients (2/30, 6.7%), both of which were resolved at follow-up; only 1 was symptomatic (silent cerebral lesion, 3.3%). In the CT/MRA subset (n = 30), severe PV narrowing (of >70%) was detected in 2 patients (2/30, 6.7%; vein level 2/128, 1.6%), of whom 1 underwent dilatation and stenting and 1 was asymptomatic; both were associated with high index values and a small inter-tag distance. In the PV durability subset (n = 30), 100/115 treated PVs (87%) were durably isolated and 18/30 patients (60.0%) had all PVs durably isolated. CONCLUSION: A DE focal CF catheter with 3D mapping integration showed a 100% acute success rate with an acceptable safety profile in the treatment of paroxysmal AF. Prespecified 3-month remapping showed notable PVI durability. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT05752487.

No Effect of Continued Antiarrhythmic Drug Treatment on Top of Optimized Pulmonary Vein Isolation in Patients With Persistent Atrial Fibrillation: Results From the POWDER-AF2 Trial.

BACKGROUND: In patients with persistent atrial fibrillation (PersAF), catheter ablation aiming for pulmonary vein isolation (PVI) is associated with moderate clinical effectiveness. We investigated the benefit of continuing previously ineffective class 1C or 3 antiarrhythmic drug therapy (ADT) in the setting of a standardized PVI-only ablation strategy. METHODS: In this multicenter, randomized controlled study, patients with PersAF (≥7 days and <12 months) despite ADT were prospectively randomized 1:1 to PVI with ADT continued versus discontinued beyond the blanking period (ADT ON versus ADT OFF). Standardized catheter ablation was performed aiming for durable isolation with stable, contiguous, and optimized radio frequency applications encircling the pulmonary veins (CLOSE protocol). Clinical visits and 1-to-7-day Holter were performed at 3, 6, and 12 months. The primary end point was any documented atrial tachyarrhythmia lasting >30 seconds beyond 3 months. Prospectively defined secondary end points included repeat ablations, unscheduled arrhythmia-related visits, and quality of life among groups. RESULTS: Of 200 PersAF patients, 98 were assigned to ADT OFF and 102 to ADT ON. The longest atrial fibrillation episode qualifying for PersAF was 28 (10-90) versus 30 (11-90) days. Clinical characteristics and procedural characteristics were similar. Recurrence of atrial tachyarrhythmia was comparable in both groups (20% OFF versus 21.2% ON). No differences were observed in repeat ablations and unscheduled arrhythmia-related visits. Marked improvement in quality of life was observed in both groups. CONCLUSIONS: In patients with PersAF, there is no benefit in continuing previously ineffective ADT beyond the blanking period after catheter ablation. The high success rate of PVI-only might be explained by the high rate of durable isolation after optimized PVI and the early stage of PersAF (POWDER-AF2). REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03437356.

Cardiac resynchronization therapy in patients with a coronary sinus reducer: a case series.

Background: Reducing venous drainage of the coronary sinus is a promising intervention for refractory angina. Coronary Sinus Reducer (CSR) System™ effectively treats patients with refractory angina, possibly by increasing coronary collateral circulation, and leads to an improvement in their symptoms and quality of life. In patients with impaired left ventricular function and electrocardiographic dyssynchrony, cardiac resynchronization therapy (CRT) is an established treatment. However, there is only one published case report of CRT in a patient implanted with a CSR system. We present the first case series of CRT in patients implanted with the CSR system. Case summary: This case series describes three patients. The first case demonstrated that CRT is feasible in patients implanted with a CSR system. The second case is the first report of a left ventricular lead extraction after CSR, and the third case was complicated due to the patient's medical history; however, CSR system implantation was feasible without major complications. Discussion: Our results suggest that CRT is feasible in patients implanted with a CSR system, and lead extraction after CSR system implantation is possible. However, lead extraction in cases of severe adhesions around the CSR system and the coronary sinus may be associated with a high risk of complications; alternative options should be discussed at an early stage.

Eliminating transseptal sheath exchange for pulsed field ablation procedures using a direct over-the-needle transseptal access with the Faradrive sheath.

AIMS: Pulsed field ablation (PFA) for pulmonary vein isolation (PVI) combines the benefits of high procedural efficacy and safety. Transseptal puncture (TSP) to obtain left atrial (LA) access during PVI remains an important source of complications during LA procedures. For PFA procedures, TSP is generally performed using a standard transseptal sheath that is then exchanged over the wire for a dedicated PFA sheath, which might be a potential source for air embolism. We aimed to prospectively evaluate the feasibility and safety of a simplified workflow using the PFA sheath (Faradrive, Boston Scientific) directly for TSP. METHODS AND RESULTS: We prospectively enrolled 100 patients undergoing PVI using PFA at two centres. TSP was performed using the PFA sheath and a standard 98 cm transseptal needle under fluoroscopic guidance. TSP via the PFA sheath was successfully performed in all patients and no complications occurred. The median time from the first groin puncture to the completed LA access was 12 min (IQR 8-16 min). CONCLUSION: An over-the-needle TSP directly with the PFA sheath proved feasible and safe in our study. This simplified workflow has the potential to reduce the risk of air embolism, to shorten procedure time, and to reduce cost.

Very High-Power Ablation for Contiguous Pulmonary Vein Isolation: Results From the Randomized POWER PLUS Trial.

BACKGROUND: Very high-power, short-duration (90-W/4-second) ablation for pulmonary vein isolation (PVI) may reduce procedural times. However, shorter applications with higher power may impact lesion quality. OBJECTIVES: In this multicenter, randomized controlled trial, the authors compared procedural efficiency, efficacy, and safety of PVI using 90-W/4-second ablation to 35/50-W ablation. METHODS: Patients with paroxysmal or persistent atrial fibrillation undergoing first-time PVI were randomized to pulmonary vein encirclement with contiguous applications using very high-power, short-duration applications (90 W over 4 seconds) or 35/50-W applications (titrated up to ablation index >550 anteriorly and >400 posteriorly). Prospective endpoints were procedural efficiency (procedure time and first-pass isolation), safety (including esophageal endoscopic evaluation), and 6-month effectiveness using repetitive Holter monitoring. RESULTS: A total of 180 patients were randomized, 90 to the 90-W group (mean age: 64.2 ± 8.9 years) and 90 to the 35/50-W group (mean age: 62.3 ± 10.8 years). Procedural time was shorter in the 90-W group vs the 35/50-W group (70 [IQR: 60-80] minutes vs 75 [IQR: 65-88.3] minutes; P = 0.009). A nonsignificant trend towards lower rates of first-pass isolation was seen in the 90-W group (83.9% vs 90%; P = 0.0852). No major complications were observed in both groups with esophageal injury occurring in 1 patient per group. At 6 months, 17% of patients in the 90-W group vs 15% in the 35/50-W group experienced recurrent arrhythmia (P = 0.681). CONCLUSIONS: Contiguous ablation using very high-power, short-duration applications results in a significant but modest reduction in procedure time with similar safety and 6-month efficacy vs a conventional approach. A hybrid approach combining both ablation modalities might be the most optimal strategy. (POWER PLUS [Very High Power Ablation in Patients With Atrial Fibrillation Schedule for a First Pulmonary Vein Isolation]; NCT04784013).

Comparison of Clinical and Economic Outcomes of an Optimized Lean Versus a Standard Transcatheter Aortic Valve Implantation Program (from SOLAR [Safe Outcomes Lean And Resourceful] Study).

The increasing prevalence of aortic stenosis (AS) and the increasing number of patients indicated for transcatheter aortic valve implantation (TAVI) can lead to increased hospital constraints. This study aimed to compare, from the hospital perspective, the costs, resource use, and 30-day clinical outcomes of patients who underwent TAVI under an optimized or standard clinical pathway. A single-center, retrospective study was conducted among patients with native AS who underwent TAVI between January 2018 and March 2021. Patients who underwent optimized lean TAVI were propensity-score matched 1:1 to those who underwent standard TAVI. In-hospital costs and 30-day clinical outcomes were compared between the 2 groups. A total of 182 patients (91 in each group) were included in the final analysis. Baseline covariates were well balanced after matching. Patients who underwent lean TAVI had shorter length of stay (median [interquartile range] 3.0 days [2.0 to 6.0] vs 6.0 days [5.0 to 9.0], p <0.001). Patients in the lean TAVI group incurred lower total costs than did those in the standard TAVI group (mean ± SD: $41,346 ± 10,062 vs $50,471 ± 15,115, p = 0.002). There was no between-group difference in 30-day all-cause mortality (2.2% vs 1.1%, p = 0.573) and pacemaker implantations (5.5% vs 6.6%, p = 0.788). Rates of procedural complications were comparable between groups. In conclusion, lean TAVI leads to hospital efficiencies without compromising patient safety. Efforts to streamline the TAVI procedure should be encouraged to improve access to TAVI for patients with AS, amid resource constraints.

Performance and safety of temperature- and flow-controlled radiofrequency ablation for ventricular arrhythmia.

AIMS: High-power ablation is effective for ventricular arrhythmia ablation; however, it increases the risk of steam pops. The aim of this study was to define the safety and efficacy of QMODE ablation in the ventricle and the risk of steam pop. METHODS AND RESULTS: Consecutive patients undergoing ventricular ablation using QDOT were included in a prospective single-centre registry. Procedural data, complications, and follow-up were systematically analysed and compared with a historical ventricular tachycardia (VT) and premature ventricular complexes (PVC) cohort ablated using STSF. QMODE (≤50 W) ablation was performed in 107 patients [age 62 ± 13 years; 76% male; VT (n = 41); PVC (n = 66)]. A total of 2456 applications were analysed [power: 45.9 ± 5.0 W with minimal power titration (90% > 95% max power); duration 26 ± 8 s; impedance drop 9.4 ± 4.7 Ω; ablation index: 569 ± 163; mean-max temperature 44.3 ± 2.6°C]. Ventricular tachycardia ablation was associated with shorter radiofrequency (RF) time and a trend towards shorter procedure times using QDOT (QDOT vs. STSF: 20.1 ± 14.7 vs. 31 ± 17 min; P = 0.002, 151 ± 59 vs. 172 ± 48 min; P = 0.06). Complications, VT recurrence, and mortality rates were comparable (QDOT vs. STSF: 2% vs. 2%; P = 0.9, 24% vs. 27%; P = 0.82, and 2% vs. 4%; P = 0.67). Five audible steam pops (0.02%) occurred. Premature ventricular complex ablation was associated with comparable RF and procedure times (QDOT vs. STSF: 4.8 ± 4.6 vs. 3.9 ± 3.1 min; P = 0.25 and 96.1 ± 31.9 vs. 94.6 ± 24.7 min; P = 0.75). Complication and PVC recurrence were also comparable (QDOT vs. STSF: 0% vs. 3%; P = 0.17 and 19% vs. 22%; P = 0.71). CONCLUSION: Ventricular ablation using QMODE ≤ 50 W is safe and effective for both VT and PVC ablation and is associated with a low risk for steam pop.

Early Experience with the Biotronik Protego ICD Lead.

Background: In the last decade, newer generation ICD leads have been developed based on mechanistic insides of priorly failing leads. The aim of our study was to assess the long-term performance and mechanisms of failure of the 2013-introduced Biotronik Protego ICD lead in a real-world population. Methods: All patients, who underwent implantation of a Protego ICD lead at the Heart Centre Lucerne (Lucerne, Switzerland) between November 2013 and March 2017, were followed up with semi-annual device-controls. The primary endpoint was defined as lead failure, secondary endpoints compromised all-cause death, (in)appropriate shocks and the need for reintervention. Results: A total of 64 patients (mean age 66.7 ± 8.7 years, 30% female) underwent implantation of a Protego ICD lead: 78% for primary prevention, 53% had underlying ischemic heart disease, and 40.6% had a dilated cardiomyopathy (DCM). Mean left ventricular ejection fraction (LVEF) was 32.6 ± 10.5%. A total of 24 patients were treated with cardiac resynchronization therapy (CRT), and their baseline LVEF improved from 27.8 ± 7.3% before to 39.8 ± 12.5 after implantation (p < 0.001). Mean time to follow-up was 5.5 ± 0.9 years. Overall, 14 patients (26.6%) suffered from at least one episode of sustained ventricular tachycardia; in total 10 patients (15.6%) died. Two patients experienced lead failure due to lead fracture after 5.5 and 5.7 years, which was clinically apparent by an abrupt rise in lead impedance (>2000 Ω) and by repetitive inappropriate shocks, respectively. Conclusions: In this retrospective observational study, the calculated annual lead failure rate of the Biotronik Protego ICD lead was 0.59% per patient­thus, the durability and long-term performance seem to be promising.

Evaluation and optimization of novel extraction algorithms for the automatic detection of atrial activations recorded within the pulmonary veins during atrial fibrillation.

BACKGROUND AND OBJECTIVE: The automated detection of atrial activations (AAs) recorded from intracardiac electrograms (IEGMs) during atrial fibrillation (AF) is challenging considering their various amplitudes, morphologies and cycle length. Activation time estimation is further complicated by the constant changes in the IEGM active zones in complex and/or fractionated signals. We propose a new method which provides reliable automatic extraction of intracardiac AAs recorded within the pulmonary veins during AF and an accurate estimation of their local activation times. METHODS: First, two recently developed algorithms were evaluated and optimized on 118 recordings of pulmonary vein IEGM taken from 35 patients undergoing ablation of persistent AF. The adaptive mathematical morphology algorithm (AMM) uses an adaptive structuring element to extract AAs based on their morphological features. The relative-energy algorithm (Rel-En) uses short- and long-term energies to enhance and detect the AAs in the IEGM signals. Second, following the AA extraction, the signal amplitude was weighted using statistics of the AA sequences in order to reduce over- and undersensing of the algorithms. The detection capacity of our algorithms was compared with manually annotated activations and with two previously developed algorithms based on the Teager-Kaiser energy operator and the AF cycle length iteration, respectively. Finally, a method based on the barycenter was developed to reduce artificial variations in the activation annotations of complex IEGM signals. RESULTS: The best detection was achieved using Rel-En, yielding a false negative rate of 0.76% and a false positive rate of only 0.12% (total error rate 0.88%) against expert annotation. The post-processing further reduced the total error rate of the Rel-En algorithm by 70% (yielding to a final total error rate of 0.28%). CONCLUSION: The proposed method shows reliable detection and robust temporal annotation of AAs recorded within pulmonary veins in AF. The method has low computational cost and high robustness for automatic detection of AAs, which makes it a suitable approach for online use in a procedural context.

Long-term follow-up after the use of the as low as reasonably achievable radiation protocol in patients with symptomatic supraventricular tachycardia.

INTRODUCTION: Catheter ablation is an effective treatment modality for patients with symptomatic supraventricular tachycardia (SVT), such as atrioventricular nodal re-entrant tachycardia (AVNRT) and typical atrial flutter (TAF). With increasingly invasive electrophysiological procedures and continuous development of ablation techniques, the aim is to reduce radiation doses for patients and the electrophysiological team. Modern methods that combine the "as low as reasonably achievable" (ALARA) protocol and three-dimensional mapping systems are now state-of-the-art procedures in the treatment of arrhythmia. This study aimed to compare the effectiveness and long-term success of the ALARA approach compared to those of conventional therapy, without using modern mapping systems. METHODS: Sixty-one patients with symptomatic SVT (37 with AVNRT, 19 with isthmus-dependent counter-clockwise TAF, and five with other SVTs) were randomised into two groups: the ALARA and conventional groups. All patients underwent successful SVT ablation. Clinical and remote follow-up was available for 59 patients after a mean period of 3.2 years. RESULTS: The mean fluoroscopy time was significantly shorter in the ALARA group (1.1 min vs. 8.4 min, p < 0.01). Regarding complications and recurrences, during a median follow-up period of 3.2 years, eight patients (13.5%) had recurrences, all of which occurred in the conventional group. CONCLUSION: This study confirmed a significantly lower radiation burden for patients and the entire electrophysiological team with the ALARA approach and a significantly increased risk of recurrence and complications with the conventional approach. The reduction in radiation time and high long-term success indicate the utility of the ALARA protocol in daily practice.

High-resolution parahisian mapping and ablation using microelectrode embedded ablation catheters.

BACKGROUND: Accurate mapping of the compact atrioventricular (AV) node is critical during ablation of a range of arrhythmias. OBJECTIVE: The purpose of this multicenter prospective study was to test the hypothesis that microelectrode (ME)-embedded catheters more accurately define the near-field compact AV node compared to conventional catheters. METHODS: For the mapping phase, detailed AV junction maps were created in 47 patients using an ME-embedded catheter. His electrograms (EGMs) detected by conventional electrodes (Hisc) and by ME (Hisµ) were annotated. For the ablation phase, AV nodal ablation (Qmode 50 W) was performed in 10 patients after pacemaker implantation, with initial Hisc-only ablation in group 1 (n = 6) and initial Hisµ ablation in group 2 (n = 4). For the clinical phase, a prospective registry of parahisian tachycardia using QDOT was obtained. RESULTS: In the mapping phase, 7.0 ± 5.4 Hisc and 8.0 ± 5.6 Hisµ points were acquired per map (n = 47). Hisµ cloud was smaller and more proximally located than Hisc cloud: (99.4 ± 74.7 mm2 vs 197.6 ± 110.6 mm2; P = .0008). Hisµ EGMs had larger amplitudes than Hisc EGMs (0.40 ± 0.38 mV vs 0.16 ± 0.1 mV; P = .0002). In the ablation phase, for group 1: Hisc-only ablation never resulted in AV block, whereas Hisµ ablation resulted in AV block after limited ablation in all patients (after 13.3 ± 9.2 s); and for group 2: Hisµ ablation always resulted in AV block after 1 application (after 14.3 ± 10.3 s). In the clinical phase, a Hisµ-avoidance strategy could avoid AV block in a prospective registry of 11 patients. CONCLUSION: ME more accurately defines the region of the compact node, and ablation in this region is associated with a high risk for AV block. ME-based mapping has the potential to significantly enhance ablation safety and efficacy.

Quality of life and healthcare utilisation improvements after atrial fibrillation ablation.

OBJECTIVE: Pulmonary vein isolation (PVI) guided by a standardised CLOSE (contiguous optimised lesions) protocol has been shown to increase clinical success after catheter ablation for paroxysmal atrial fibrillation (PAF). This study analysed healthcare utilisation and quality of life (QOL) outcomes from a large multicentre prospective study, measured association between QOL and atrial fibrillation (AF) burden and identified factors associated with lack of QOL improvement. METHODS: CLOSE-guided ablation was performed in 329 consecutive patients (age 61.4 years, 60.8% male) with drug-refractory PAF in 17 European centres. QOL was measured at baseline and 12 months post-ablation via Atrial Fibrillation Effect on QualiTy of Life Survey (AFEQT) and EuroQoL EQ-5D-5L questionnaires. All-cause and cardiovascular hospitalisations and cardioversions over 12 months pre-ablation and post-ablation were recorded. Rhythm monitoring included weekly and symptom-driven trans-telephonic monitoring, plus ECG and Holter monitoring at 3, 6 and 12 months. AF burden was defined as the percentage of postblanking tracings with an atrial tachyarrhythmia ≥30 s. Continuous measures across multiple time points were analysed using paired t-tests, and associations between various continuous measures were analysed using independent sample t-tests. Each statistical test used two-sided p values with a significance level of 0.05. RESULTS: Both QOL instruments showed significant 12-month improvements across all domains: AFEQT score increased 25.1-37.5 points and 33.3%-50.8% fewer patients reporting any problem across EuroQoL EQ-5D-5L domains. Overall, AFEQT improvement was highly associated with AF burden (p=0.009 for <10% vs ≥10% burden, p<0.001 for <20% vs ≥20% burden). Cardiovascular hospitalisations were significantly decreased after ablation (42%, p=0.001). Patients without substantial improvement in AFEQT (55/301, 18.2%) had higher AFEQT and CHA2DS2-VASc scores at baseline, and higher AF burden following PVI. CONCLUSIONS: QOL improved and healthcare utilisation decreased significantly after ablation with a standardised CLOSE protocol. QOL improvement was significantly associated with impairment at baseline and AF burden after ablation. TRIAL REGISTRATION NUMBER: NCT03062046.

Biosense Webster's QDOT Micro™ radiofrequency ablation catheter.

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.

Reduction of MANTA-associated vascular complications after implementation of key insights on failure mechanisms.

OBJECTIVES: Report MANTA-associated vascular complications after implementation of key insights on failure mechanisms. BACKGROUND: The MANTA vascular closure device is utilized to close large-bore arterial access sites. We have previously identified and published the mechanisms and predictors of MANTA-associated vascular complications. We identified three distinct mechanisms leading to MANTA-associated vascular complications, predictors were a common femoral artery (CFA) diameter <6 mm and clinically established peripheral artery disease (PAD). METHODS: We compared 100 consecutive patients of the initial cohort (first n = 100) with consecutive patients in which the key insights acquired in the initial cohort were implemented (second n = 100). RESULTS: The initial cohort (n = 100 patients) had a MANTA-related vascular complication rate of 11% (7% major and 4% minor), and 14% MANTA-related bleeding complications. In a subsequent cohort of n = 100 patients, we applied the abovementioned findings: we did not use the MANTA device if the CFA was <6 mm and in patients with PAD. In addition, femoral puncture was ultrasound guided. This strategy led to a decline in MANTA-related vascular complication rates: 2% (1% major and 1% minor) p = .03, as well as a reduction in MANTA-related bleeding complications to 5% p = .01. To the best of our knowledge, this is the lowest rate of MANTA-related vascular complication reported thus far. CONCLUSIONS: Our strategy achieves low MANTA-related vascular and bleeding complication rates. Careful and critical examination of complications can lead to rapid identification of complication mechanism and its predictors. In turn, rapid implementation of these insights can lead to a decline in complication rates.