Single center experience with the novel rotating dilator sheath TightRailTM Sub-C in transvenous lead extraction.

INTRODUCTION: Transvenous lead extraction has become a frequent procedure in the context of device lead management and various tools are available. The aim of this study was to investigate the efficacy and safety of the novel short rotating dilator sheath TightRailTM Sub-C (Sub-C) in transvenous lead extraction. METHODS: For this retrospective single-center analysis, we included consecutive patients undergoing transvenous lead extraction using the Sub-C from January 2018 until February 2020 at the University Heart Center Zurich. RESULTS: A total of 87 leads were extracted within 45 patients using the Sub-C extraction sheath. The mean dwell time of the leads was 112 ± 9.1 months. Complete procedural success was achieved in 95.6% (43/45) and clinical procedural success in 97.8% (44/45). Two major complications (4.4%, 2/45) occurred, but neither was directly related to the Sub-C. CONCLUSION: This retrospective single-center analysis suggests that transvenous lead extraction with a routine use of the TightRailTM Sub-C extraction sheath is a safe strategy resulting in high success rates that may offer useful theoretical benefits. Future studies are needed to evaluate the incremental benefit of a routine use of short extraction sheaths including the Sub-C during TLE procedures.

Catheter ablation of atrial fibrillation with a multi-electrode radiofrequency balloon; first and early two centre experience in Europe.

INTRODUCTION: The Heliostar™ ablation system is a novel RF balloon ablation technology with an integrated three-dimensional mapping system. Here, we describe our early experience and procedural outcomes using this technology for atrial fibrillation catheter ablation. METHODS: We sought to comprehensively assess the first 60 consecutive patients undergoing pulmonary vein isolation using the novel HELISOTAR™ RF balloon technology including procedural outcomes. A comparison of the workflow between two different anaesthetic modalities (conscious sedation [CS] vs. general anaesthesia [GA]) was made. Procedural data were collected prospectively from two high-volume centers (Barts Heart Centre, UK and University Hospital of Zurich, Zurich). A standardized approach for catheter ablation was employed. RESULTS: A total of 35 patients had the procedure under CS and the remaining under GA. Mean procedural and fluoroscopy times were 84 ± 33 min and 1.1 min. The median duration of RF energy application was 7 (5-9.8) mins per patient. All veins were successfully isolated, and the median isolation time was 10 (7-15) seconds. Our cohort's rate of procedural complications was low, with no mortality within 30 days postprocedure. CONCLUSION: Our early experience shows that catheter ablation using the Heliostar™ technology can be performed efficiently and safely; however, long-term data is yet to be established. Low fluoroscopy requirements, short learning curves and use of this technology with CS is possible, including the use of an oesophageal temperature probe.

Efficacy and Safety of Leadless Pacemaker Implantation in Octogenarians.

INTRODUCTION: Long-term complication rates in standard transvenous pacemakers are reported around 4-12% with a higher incidence in the elderly population. We report our experience in octogenarians undergoing leadless pacemaker implantation in two large-volume centers in Switzerland. METHODS: Consecutive patients undergoing leadless pacemaker implantation at two Swiss large volume centers (University Hospital Zurich, Zurich and Cardiocentro Ticino Institute, Lugano) between October 2015 and March 2020 were included in this retrospective analysis. Demographic information, clinical data, and procedural characteristics were recorded at the day of implantation and during follow-up. RESULTS: Two hundred and twenty patients (mean age 80.6 ± 7.7 years, male 66%) were included. The main indication for pacemaker implantation was slow ventricular rate atrial fibrillation (111 of 220 patients, 50.4%). Out of the 220 patients, 124 (56.3%) were ≥80 years. Overall successful implantation rate was 98.6%. In the octogenarian population, the median procedure time (45 ± 20.2 min vs. 40 ± 19.6 min, p = 0.03) and radiation duration (6.1 ± 8.2 min vs. 5.0 ± 7.2 min, p = 0.03) were longer compared to patients <80 years. Major complications (2.7%, n = 6) and device measurements during follow-up were similar between patients ≥80 and <80 years. CONCLUSION: Implantation of a leadless pacemaker device in octogenarians is safe and effective with a similarly low complication rate compared to non-octogenarians.

Clinical relevance of lung transplantation for COVID-19 ARDS: a nationwide study.

BACKGROUND: Although the number of lung transplantations (LTx) performed worldwide for COVID-19 induced acute respiratory distress syndrome (ARDS) is still low, there is general agreement that this treatment can save a subgroup of most severly ill patients with irreversible lung damage. However, the true proportion of patients eligible for LTx, the overall outcome and the impact of LTx to the pandemic are unknown. METHODS: A retrospective analysis was performed using a nationwide registry of hospitalised patients with confirmed severe acute respiratory syndrome coronavirus type 2 (SARS-Cov-2) infection admitted between January 1, 2020 and May 30, 2021 in Austria. Patients referred to one of the two Austrian LTx centers were analyzed and grouped into patients accepted and rejected for LTx. Detailed outcome analysis was performed for all patients who received a LTx for post-COVID-19 ARDS and compared to patients who underwent LTx for other indications. RESULTS: Between January 1, 2020 and May 30, 2021, 39.485 patients were hospitalised for COVID-19 in Austria. 2323 required mechanical ventilation, 183 received extra-corporeal membrane oxygenation (ECMO) support. 106 patients with severe COVID-19 ARDS were referred for LTx. Of these, 19 (18%) underwent LTx. 30-day mortality after LTx was 0% for COVID-19 ARDS transplant recipients. With a median follow-up of 134 (47-450) days, 14/19 patients are alive. CONCLUSIONS: Early referral of ECMO patients to a LTx center is pivotal in order to select patients eligible for LTx. Transplantation offers excellent midterm outcomes and should be incorporated in the treatment algorithm of post-COVID-19 ARDS.

Feasibility, Efficiency, and Safety of Zero-Fluoroscopy Catheter Interventions for Right-Sided Cardiac Arrhythmias Using Only Electroanatomic Mapping.

INTRODUCTION: Fluoroscopy is traditionally used for catheter interventions in electrophysiology but carries a long-term health risk. Besides additional invasive procedures to achieve zero-fluoroscopy (ZF) interventions, electroanatomic mapping may be an alternative to fluoroscopy without the need of additional procedures. We aimed to investigate the feasibility, safety, and efficiency of a ZF approach using only electroanatomic mapping (ZF) compared to a conventional fluoroscopic (CF) approach for patients with right sided cardiac arrhythmias. METHODS: We performed a single centre retrospective cohort study of consecutive patients undergoing catheter interventions for electrophysiologic procedures from January 2019 to December 2020. Patients with left-sided arrhythmias, focal cryoablation, implanted endocardial devices, or additional interventions requiring fluoroscopy were excluded. RESULTS: 202 patients underwent a ZF and 126 patients underwent a CF approach for right-sided cardiac arrhythmias. Apart from atrial fibrillation (ZF 16% vs. CF 9%, p = 0.044), baseline demographics were similar in both groups. Acute success rate was 100% in the ZF group and 97.9% in the CF group. Mean procedure time was lower in the ZF group (70 ± 36 vs. 87 ± 44 min, p = 0.0001), while ablation time (356 ± 324 vs. 320 ± 294 s, p = 0.157) was similar. Total complication rate was low in general (1.0 % major, 2% minor complications) and without a difference between both groups. CONCLUSION: A ZF approach using only electroanatomic mapping without additional invasive procedures to diagnose and treat right-sided cardiac arrhythmias is feasible, efficient, and safe.

Leadless Pacemaker Implantation in the Emergency Bradyarrhythmia Setting: Results from a Multicenter European Registry.

Background. Data on leadless pacemaker (LPM) implantation in an emergency setting are currently lacking. Objective. We aimed to investigate the feasibility of LPM implantation for emergency bradyarrhythmia, in patients referred for urgent PM implantation, in a large, multicenter, real-world cohort of LPM recipients. Methods. Two cohorts of LPM patients, stratified according to the LPM implantation scenario (patients admitted from the emergency department (ED+) vs. elective patients (ED−)) were retrieved from the iLEAPER registry. The primary outcome of the study was a comparison of the peri-procedural complications between the groups. The rates of peri-procedural characteristics (overall procedural and fluoroscopic duration) were deemed secondary outcomes. Results. A total of 1154 patients were enrolled in this project, with patients implanted due to an urgent bradyarrhythmia (ED+) representing 6.2% of the entire cohort. Slow atrial fibrillation and complete + advanced atrioventricular blocks were more frequent in the ED+ cohort (76.3% for ED+ vs. 49.7% for ED−, p = 0.025; 37.5% vs. 27.3%, p = 0.027, respectively). The overall procedural times were longer in the ED+ cohort (60 (45−80) mins vs. 50 (40−65) mins, p < 0.001), showing higher rates of temporary pacing (94.4% for ED+ vs. 28.9% for ED−, p < 0.001). Emergency LPM implantation was not correlated with an increase in the rate of major complications compared to the control group (6.9% ED+ vs. 4.2% ED−, p = 0.244). Conclusion. LPM implantation is a feasible procedure for the treatment of severe bradyarrhythmia in an urgent setting. Urgent LPM implantation was not correlated with an increase in the rate of major complications compared to the control group, but it was associated with longer procedural times.

Left femoral venous access for leadless pacemaker implantation: patient characteristics and outcomes.

AIMS: Leadless pacing has become an alternative approach for patients requiring a single-chamber pacemaker. Conventionally, leadless Micra Transcatheter Pacing System (TPS) pacemakers are implanted via a right femoral venous access. However, due to various reasons, a left-sided femoral venous approach may be necessary. We hypothesized that a left-sided femoral venous approach is as safe and effective when compared with a right-sided approach. We assessed indications, procedural characteristics, safety and mid-term outcomes of Micra TPS implantation via a left femoral venous approach when compared with the conventional right-sided approach. METHODS AND RESULTS: In this retrospective single-centre analysis, 143 consecutive patients undergoing Micra TPS implantation were included. 87% (125/143) underwent Micra TPS implantation via a right, and 13% (18/143) via a left femoral venous access. The mean age at implantation was 79.8 ± 7.5 years. Acute procedural success, mean procedure and fluoroscopy times as well as device parameters at implantation and follow-up (mean 15 ± 11.5 months) were similar between the two groups. Five major complications (3.5%) were encountered, all using a right-sided approach. After a transfemoral TAVI procedure, left femoral venous access was used in 42% of cases when compared with 8% in the remaining population (P = 0.003). CONCLUSIONS: A left femoral venous access for Micra TPS implantation is safe and effective with an excellent implantation success rate similar to a conventional right femoral venous access without longer implantation and fluoroscopy times. The most frequent reason for choosing left vs. right femoral venous access was a previous transfemoral TAVI procedure.

Snare technique for coronary sinus cannulation in cardiac resynchronization therapy.

PURPOSE: Biventricular pacing is a mainstay of therapy for patients with heart failure. However, lead implantations may fail due to anatomical reasons including the impossibility of coronary sinus cannulation. METHODS AND RESULTS: A dual approach from the subclavian vein using a snare through a sheath and from the femoral vein using a steerable electrophysiology catheter was performed. Once the snare hooked the catheter, the latter was advanced into the coronary sinus and finally, the sheath could also be advanced in an "over-the-wire" technique. CONCLUSION: The snare technique for coronary sinus cannulation offers a "bail-out" strategy for left ventricular lead implantation.

Leadless Pacemaker Implantation, Focusing on Patients With Conduction System Disorders Post-Transcatheter Aortic Valve Replacement: A Retrospective Analysis.

Background: Impairment of the conduction system is a common complication of transcatheter aortic valve replacement (TAVR), which is typically performed in elderly patients. A leadless pacemaker (LP) may be a suitable option in this frail population, but the available scientific data concerning the efficacy and safety of leadless pacing after TAVR are sparse. The purpose of this analysis was to evaluate the efficacy and safety of LP implantation in patients with relevant bradycardias after TAVR, compared to other indications. Methods: Consecutive patients were retrospectively enrolled. Demographics, background heart diseases, interventional parameters, and follow-up data were collected. Results: A total of 257 consecutive patients who underwent LP implantation were included. In 26 patients, the device was implanted due to bradycardias after TAVR (TAVR group), whereas the remaining 231 patients were in the population without previous TAVR (non-TAVR group). The mean implantation duration (56 ± 22 minutes in the TAVR group vs 48 ± 20 minutes in the non-TAVR group; P = not significant [NS]) and the implantation success rate (100% in the TAVR group vs 98.7% in the non-TAVR group; P = NS) were similar in the 2 cohorts. No significant differences occurred in pacing parameters (sensing, impedance, and threshold, respectively) between the 2 groups, either at implantation or during follow-up. A total of 8 major periprocedural complications (3.1% of patients in total; 3.8% in the TAVR group vs 3.0% in the non-TAVR group; P = NS) occurred within 30 days, without significant difference between the 2 groups. Conclusions: LP implantation appears to be safe and effective in patients after TAVR, and therefore, this procedure is a suitable option for this often old and frail population.

Contexte: L'atteinte du système de conduction cardiaque est une complication courante du remplacement valvulaire aortique par cathéter (RVAC), une intervention habituellement pratiquée chez les patients âgés. Un stimulateur cardiaque sans sonde peut être une option convenable pour cette population fragile, mais les données scientifiques actuelles concernant l'efficacité et l'innocuité de la stimulation sans sonde après un RVAC sont fragmentaires. Cette analyse visait à évaluer l'efficacité et l'innocuité de l'implantation d'un stimulateur cardiaque sans sonde chez des patients atteints de bradycardies pertinentes après un RVAC, comparativement à d'autres indications. Méthodologie: Des patients consécutifs ont été recrutés de manière rétrospective. Les données démographiques, les maladies cardiaques sous-jacentes, les paramètres interventionnels et les données de suivi ont été colligés. Résultats: Un total de 257 patients consécutifs qui se sont fait implanter un stimulateur cardiaque sans sonde ont été inclus. Chez 26 patients, le dispositif a été implanté en raison d'une bradycardie après un RVAC (groupe RVAC), alors que les 231 autres patients formaient la population sans RVAC antérieur (groupe sans RVAC). La durée moyenne de l'intervention d'implantation (56 ± 22 minutes dans le groupe RVAC vs 48 ± 20 minutes dans le groupe sans RVAC; p = non significatif [NS]) et le taux de réussite de l'implantation (100 % dans le groupe RVAC vs 98,7 % dans le groupe sans RVAC; p = NS) étaient similaires dans les deux cohortes. Aucune différence significative n'a été observée dans les paramètres de stimulation (sensibilité, impédance et seuil, respectivement) entre les 2 groupes, que ce soit au moment de l'implantation ou pendant le suivi. Un total de 8 complications périopératoires majeures (3,1 % de l'ensemble des patients; 3,8 % dans le groupe RVAC vs 3,0 % dans le groupe sans RVAC; p = NS) sont survenues dans les 30 jours, sans différence notable entre les 2 groupes. Conclusions: L'implantation d'un stimulateur cardiaque sans sonde semble sûre et efficace après un RVAC; par conséquent, cette intervention représente une option convenable pour cette population souvent âgée et fragile.

Leadless Pacemaker Implantation in Patients With a Prior Conventional Pacing System.

Background: Leadless pacing has been established as an alternative approach to transvenous devices for selected patients. Often, leadless pacemaker (LP) implantation is a de novo procedure, but in an increasing number of patients, an LP is used after previous implantation of a conventional pacing system (CPS). Methods: A retrospective analysis was conducted of the efficacy and safety of LP implantation in the context of a previously implanted CPS, from 2 large Swiss centres. Results: A total of 257 consecutive patients undergoing LP implantation were included. They were divided into 2 groups: group 1 consisted of 233 patients who did not have a previous CPS, and group 2 consisted of 24 patients with an in situ CPS. In group 2, a total of 20 patients (83%) required transvenous lead extraction due to infection, malfunction, or other reasons. In 3 patients with device-related infection, lead extraction and LP implantation was performed as a single procedure, whereas in the remaining 11 cases, a time window occurred between the 2 procedures (median: 11.5 days; range: 2-186 days). Electrical device parameters at implantation and during follow-up did not differ between the 2 groups (mean: 12.5 ± 9.3 months). Eight major periprocedural complications (3.1%) were encountered (4 pericardial effusions, 3 instances of femoral bleeding, and 1 instance of intra-abdominal bleeding) in the entire cohort within a 30-day period. No complications occurred in the group with a previous device. No infections were registered, even when complete extraction of an infected CPS was performed prior to LP implantation. Conclusions: Implantation of an LP in patients with a prior CPS (with or without extraction of the previous system) was effective and safe in our population of patients.

Contexte: La stimulation cardiaque sans fil a été établie comme une solution de substitution aux dispositifs transveineux chez certains patients. L'implantation d'un stimulateur cardiaque sans fil est souvent une intervention de novo, mais chez un nombre croissant de patients, ce type de stimulateur est utilisé après l'implantation d'un stimulateur classique. Méthodologie: Une analyse rétrospective de l'efficacité et de l'innocuité de la stimulation cardiaque sans fil dans le contexte de l'implantation d'un stimulateur classique a été réalisée dans deux grands centres suisses. Résultats: Un total de 257 patients consécutifs ayant subi l'implantation d'un stimulateur cardiaque sans fil ont été inclus. Les patients étaient répartis dans deux groupes; le groupe 1 était composé de 233 patients non porteurs d'un stimulateur classique, et le groupe 2, de 24 patients porteurs d'un stimulateur classique in situ. Dans le groupe 2, 20 patients au total (83 %) ont eu besoin d'une extraction de la sonde transveineuse en raison d'une infection, d'un défaut de fonctionnement, ou pour d'autres motifs. Chez 3 patients présentant une infection liée au stimulateur, l'extraction de la sonde et l'implantation d'un stimulateur cardiaque sans fil ont été réalisées simultanément, tandis que dans les 11 autres cas, il s'est écoulé un temps médian de 11,5 jours entre les deux interventions (min.-max. : 2-186 jours). Les paramètres relatifs au dispositif électrique au moment de l'implantation et pendant le suivi n'étaient pas différents entre les deux groupes (moyenne : 12,5 ± 9,3 mois). Huit complications périopératoires importantes (3,1 %) sont survenues (4 cas d'épanchement péricardique, 3 cas d'hémorragie fémorale et 1 cas d'hémorragie intra-abdominale) dans l'ensemble de la cohorte au cours d'une période de 30 jours. Aucune complication ne s'est produite dans le groupe de patients porteurs d'un stimulateur classique. On n'a enregistré aucun cas d'infection, même lorsque l'extraction complète du stimulateur classique infecté a été effectuée avant l'implantation du stimulateur cardiaque sans fil. Conclusions: L'implantation d'un stimulateur cardiaque sans fil chez les patients porteurs d'un stimulateur classique (avec ou sans extraction de ce stimulateur) était une intervention efficace et sûre dans cette population de patients.

Implantable cardiac monitors: artificial intelligence and signal processing reduce remote ECG review workload and preserve arrhythmia detection sensitivity.

Introduction: Implantable cardiac monitors (ICMs) provide long-term arrhythmia monitoring, but high rates of false detections increase the review burden. The new "SmartECG" algorithm filters false detections. Using large real-world data sets, we aimed to quantify the reduction in workload and any loss in sensitivity from this new algorithm. Methods: Patients with a BioMonitor IIIm and any device indication were included from three clinical projects. All subcutaneous ECGs (sECGs) transmitted via remote monitoring were classified by the algorithm as "true" or "false." We quantified the relative reduction in workload assuming "false" sECGs were ignored. The remote monitoring workload from five hospitals with established remote monitoring routines was evaluated. Loss in sensitivity was estimated by testing a sample of 2000 sECGs against a clinical board of three physicians. Results: Of our population of 368 patients, 42% had an indication for syncope or pre-syncope and 31% for cryptogenic stroke. Within 418.5 patient-years of follow-up, 143,096 remote monitoring transmissions contained 61,517 sECGs. SmartECG filtered 42.8% of all sECGs as "false," reducing the number per patient-year from 147 to 84. In five hospitals, nine trained reviewers inspected on average 105 sECGs per working hour. This results in an annual working time per patient of 83 min without SmartECG, and 48 min with SmartECG. The loss of sensitivity is estimated as 2.6%. In the majority of cases where true arrhythmias were rejected, SmartECG classified the same type of arrhythmia as "true" before or within 3 days of the falsely rejected sECG. Conclusion: SmartECG increases efficiency in long-term arrhythmia monitoring using ICMs. The reduction of workload by SmartECG is meaningful and the risk of missing a relevant arrhythmia due to incorrect filtering by the algorithm is limited.

Challenges and pitfalls during CRT implantation in patients with persistent left superior vena cava.

BACKGROUND: Persistent left superior vena cava (PLSVC) is a rare venous anomaly, affecting 0.3-0.5% of the general population. Cardiac resynchronization therapy (CRT) implantation in patients with PLSVC is challenging due to a complex anatomy. Moreover, data on CRT implantation in this patient population is scarce. Our aim was to report a series of patients with PLSVC and CRT implantation focusing on challenges and pitfalls. METHODS: Electronic medical databases on patients with CRT implantation at the University Heart Centers in Zurich, Switzerland, and Lübeck, Germany, were screened for individuals with a PLSVC. Clinical and demographic characteristics as well as procedural data were reported in all patients. RESULTS: This study presents six cases with a median age of 66 years. CRT implantation was successful in five patients, leading to a reduced QRS duration and improved left ventricular ejection fraction. Atrial fibrillation, ischemic cardiomyopathy, valvular heart disease, and dilated cardiomyopathy were observed in this group as underlying conditions. Specialized tools, such as active fixation left ventricular leads, were utilized. One patient experienced major complications. CONCLUSIONS: This case series shows that although challenging, conventional endovascular CRT implantation is feasible in PLSVC patients. Specialized tools for visualization and fixation may help. Our experiences highlight the importance of preprocedural evaluation of the anatomy and precise intervention planning.

Five-year outcomes of different techniques for minimally invasive mitral valve repair in Barlow's disease.

OBJECTIVES: Barlow's disease is a specific sub-form of mitral valve (MV) disease, characterized by diffuse excessive tissue and multi segment prolapse. The anterolateral mini-thoracotomy represents the standard access for MV regurgitation in many centres. It still remains unclear which surgical technique provides the best results. Therefore, the aim of this study was to compare operative safety and mid-term outcomes after (i) isolated annuloplasty, (ii) use of additional artificial chordae or (iii) leaflet resection in patients suffering from Barlow's disease undergoing minimally invasive MV repair. METHODS: A consecutive series of patients suffering from Barlow's disease undergoing minimally invasive MV surgery between 2001 and 2020 were analysed (n = 246). Patients were grouped and analysed according to the used surgical technique. The primary outcome was a modified Mitral Valve Academic Research Consortium combined end-point of mortality, reoperation due to repair failure or reoccurrence of severe mitral regurgitation within 5 years. The secondary outcome included operative success and safety up to 30 days. RESULTS: No significant difference was found between the 3 surgical techniques with regard to operative safety (P = 0.774). The primary outcome did not differ between groups (P = 0.244). Operative success was achieved in 93.5% and was lowest in the isolated annuloplasty group (77.1%). Conversion to MV replacement was increased in patients undergoing isolated annuloplasty (P < 0.001). CONCLUSIONS: Isolated annuloplasty, use of additional artificial chordae and leaflet resection represent feasible techniques in Barlow patients undergoing minimally invasive MV surgery with comparable 5-year results. In view of the increased conversion rate in the annuloplasty group, the pathology should not be oversimplified.

Electrocardiographic predictors of atrial mechanical sensing in leadless pacemakers.

BACKGROUND: Leadless pacemakers (LPs) capable of VDD pacing allow for atrioventricular synchrony through mechanical sensing of atrial contraction. However, mechanical sensing is less reliable and less predictable than electrical sensing. OBJECTIVE: The purpose of this study was to evaluate P-wave amplitude during sinus rhythm from preoperative 12-lead electrocardiograms (ECGs) as a predictor for atrial mechanical sensing in patients undergoing VDD LP implantation. METHODS: Consecutive patients undergoing VDD LP implantation were included in this 2-center prospective cohort study. ECG parameters were evaluated separately and in combination for association with the signal amplitude of atrial mechanical contraction (A4). RESULTS: Eighty patients (median age 82 years; female 55%; mean body mass index [BMI] 25.8 kg/m2) were included in the study and 61 patients in the A4 signal analysis (19 patients in VVI mode during follow-up). Absolute (aVL, aVF, V1, V2) and BMI-adjusted (I, II, aVL, aVF, aVR, V1, V2) P-wave amplitudes from baseline ECGs demonstrated a statistically significant positive correlation with A4 signal amplitude (all P <.05). A combined P-wave signal amplitude of at least 0.2 mV in V1 and aVL was predictive, with specificity of 83% (95% confidence interval 67%-100%) for A4 signal ≥1 m/s2. We found a significant correlation of A4 signal amplitude and overall atrioventricular synchrony (P = .013). CONCLUSION: P-wave amplitudes in ECG leads aVL and V1 can predict A4 signal amplitude in patients with VDD LP and therefore the probability of successful AV synchronous pacing.

Success and Complication Rates of Transvenous Lead Extraction in a Developing High-Volume Extraction Center: The Zurich Experience.

INTRODUCTION: Transvenous lead extractions are increasingly performed for malfunction or infection of cardiac implantable electronic devices, but they harvest a potential for complications and suboptimal success. Apart from multicenter registries and reports from highly experienced single centers, the outcome in individual newly developing high-volume centers starting a lead extraction program is less well established. We aimed to evaluate the clinical and radiological success and complication rate at our center, having started a lead extraction program less than a decade ago. METHODS: We retrospectively analyzed patients who underwent transvenous lead extraction at the University Hospital Zurich from 2013 to 2021 regarding success as well as complications and compared our results to previously reported outcome rates. RESULTS: A total of 346 patients underwent 350 transvenous lead extractions from January 2013 to December 2021. Combined radiological success was achieved in 97.7% and clinical success in 96.0% of interventions. Procedure-related major complications occurred in 13 patients (3.7%). Death within 30 days after transvenous lead extractions occurred in 13 patients (3.7%), with a procedure-related mortality of 1.4% (five patients). SUMMARY: Transvenous lead extractions in newly developing high-volume centers can be performed with high clinical and radiological success rates, but procedure-related major complications may affect a relevant number of patients. Compared to large single or multicenter registries of experienced centers, the success rate may be lower and the complication rate higher in centers newly starting with lead extraction, which may have important implications for patient selection, procedural planning, proctoring, and safety measures.

Distinctive characteristics of His bundle potentials in patients with atrioventricular nodal reentrant tachycardia.

BACKGROUND: His bundle (HB) potentials vary in amplitude and duration in patients with and without slow pathways. The aim of this study was to determine the characteristics of HB potentials and to elucidate whether they can provide clues for identification of slow pathway (SP). METHODS: The present research prospectively studied the electrophysiological findings of 162 patients with symptomatic atrioventricular nodal reentrant tachycardia (AVNRT) due to slow-fast or fast-slow type and atrioventricular reentrant tachycardia (AVRT). Maximal HB potential (HBmax, HB with the highest amplitude) among HB cloud was recorded in both groups. For AVNRT patients, the following were measured: (1) AH interval at the "jump" during programmed atrial stimulation (A2H2, taken as a reflection of SP conduction time); (2) Distance from HBmax to the successful SP ablation site (HBmax-ABL) and from HBmax to the ostium of coronary sinus (HBmax-CSO). RESULTS: HBmax was 0.29 ± 0.10 mV in AVNRT patients, whereas it was 0.17 ± 0.05 mV in AVRT group (p < 0.0001). Likewise, the HBmax duration was 22 ± 5 ms in AVNRT group and 16 ± 3 ms in AVRT group (p < 0.0001). The area under the receiver operating characteristic curve of HBmax amplitude in AVNRT patients was 0.86 and the optimal HBmax cut-off to predict AVNRT was ≥ 0.22 mV with a sensitivity of 0.78 and specificity of 0.84. HBmax-CSO was positively correlated with HBmax-ABL, and HBmax-ABL was positively correlated with A2H2. CONCLUSIONS: HBmax amplitudes were higher and durations longer in patients with AVNRT, as compared to those with AVRT. Moreover, the distance between HBmax and successful ablation site was positively correlated with the SP conduction time and with the distance from HBmax to the CSO.

3D Atrial Strain for Predicting Recurrence of Atrial Fibrillation after Pulmonary Vein Isolation.

AIMS: Association of two-(2D) and three-dimensional (3D) left atrial strain (LAS) and low-voltage area (LVA) with recurrence of atrial fibrillation (AF) after pulmonary vein isolation (PVI) was assessed. METHODS AND RESULTS: 3D LAS, 2D LAS, and LVA were obtained in 93 consecutive patients undergoing PVI and recurrence of AF was analyzed prospectively. AF recurred in 12 patients (13%). The 3D left atrial reservoir strain (LARS) and pump strain (LAPS) were lower in patients with recurrent AF than without (p = 0.008 and p = 0.009, respectively). In univariable Cox regression, 3D LARS or LAPS were associated with recurrent AF (LARS: HR = 0.89 (0.81-0.99), p = 0.025; LAPS: HR = 1.40 (1.02-1.92), p = 0.040), while other values were not. Association of 3D LARS or LAPS with recurrent AF was independent of age, body mass index, arterial hypertension, left ventricular ejection fraction, and end-diastolic volume index and left atrial volume index in multivariable models. Kaplan-Meier curves revealed that patients with 3D LAPS < -5.9% did not exhibit recurrent AF, while those >-5.9% had a significant risk of recurrent AF. CONCLUSIONS: 3D LARS and LAPS were associated with recurrent AF after PVI. Association of 3D LAS was independent of relevant clinical and echocardiographic parameters and improved their predictive value. Hence, they may be applied for outcome prediction in patients undergoing PVI.

A qualitative improvement program for minimally invasive mitral surgery: technical advancements ameliorate outcome and operative times.

OBJECTIVES: Minimally invasive mitral valve surgery (MIMVS) has evolved over the last 2 decades. The aim of the study was to identify the impact of era and technical improvements on perioperative outcome after MIMVS. METHODS: A tota of 1000 patients (mean age: 60.8 ± 12.7 years, 60.3% male) underwent video-assisted or totally endoscopic MIMVS between 2001 and 2020 in a single institution. Three technical modalities were introduced during the observed period: (i) 3D visualization, (ii) use of premeasured artificial chordae (PTFE loops) and (iii) preoperative CT scans. Comparisons were made before and after the introduction of technical improvements. RESULTS: A total of 741 patients underwent isolated mitral valve (MV) procedure, whereas 259 received concomitant procedures. These consisted of tricuspid valve repair (208), left atrium ablation (145) and persistent foramen ovale or atrial septum defect (ASD) closure (172). The aetiology was degenerative in 738 (73.8%) patients and functional in 101 patients (10.1%). A total of 900 patients received MV repair (90%), and 100 patients (10%) underwent MV replacement. Perioperative survival was 99.1%, and periprocedural success 93.5% with a periprocedural safety of 96.3%. Improvement in periprocedural safety attributed to the lower rates of postoperative low output (P = 0.025) and less reoperations for bleeding (P < 0.001). 3D visualization improved cross-clamp (P = 0.001) but not cardiopulmonary bypass times. The use of loops and preoperative CT scan both had no impact on periprocedural success or safety but improved cardiopulmonary bypass and cross-clamp times (both P < 0.001). CONCLUSIONS: Increased surgical experience improves safety in MIMVS. Technical improvements are related to increased operative success and decreased operative times in patients undergoing MIMVS.