Safety and Efficacy of Mini-invasive left atrial appendage closure : a propensity score analysis.

BACKGROUND: Left atrial appendage closure (LAAC) for stroke prevention is validated in patients with non-valvular atrial fibrillation (NVAF) contraindicated to oral anticoagulation. General anesthesia (GA) is often used for procedural guidance by trans-oesophageal echocardiography (TEE); however, its use may be challenging in some patients. The aim of the study was to evaluate the safety and the mid-term efficacy of a mini-invasive LAAC strategy using micro-TEE under procedural sedation. METHODS: Comparison by propensity score of two cohorts of consecutive patients who underwent LAAC: standard TEE-guided LAAC (3D-TEE under GA) and, mini-invasive LAAC strategy (micro-TEE under procedural sedation). The primary endpoint was a composite of embolic or bleeding events, significant per-procedural complication, and cardiovascular deaths within 3 months after LAAC. RESULTS: In total, 432 patients were included (78.7±8 years old, 32.4% of women, CHA2DS2VASC score:4.9±1.1); 127 patients underwent mini-invasive LAAC strategy and were compared to 305 patients standard TEE-guided LAAC. The mini-invasive strategy was acheived in 122/127 (96.1%) planned patients. The primary endpoint occurred in 11.2% of patients from the mini-invasive LAAC strategy group and in 10.3% of patients from the standard TEE group (absolute difference = 0.9%[-6.4; 4.5], hazard-ratio=1.11[0.56; 2.19], p=0.76). Procedural times, fluoroscopy duration and hospital stays were shorter in the mini-invasive LAAC strategy group (p<0.001). CONCLUSIONS: The mini-invasive LAAC strategy is safe and effective compared to the standard TEE-guided LAAC strategy. A mini-invasive LAAC strategy may also be an important tool to help physicians to treat more patients as LAAC indications evolve in the future.

Current Role of Electrocardiographic Imaging in Patient Selection for Cardiac Resynchronization Therapy.

Cardiac resynchronization therapy (CRT) is a recognized therapy for heart failure with altered ejection fraction and abnormal left ventricular activation time. Since the introduction of the therapy, a 30% rate of non-responders is observed and unchanged. The 12-lead ECG remains the only recommended tool for patient selection to CRT. The 12-lead ECG is, however, limited in its inability to provide a precise pattern of regional electrical activity. Electrocardiographic imaging (ECGi) provides a non-invasive detailed mapping of cardiac activation and therefore appears as a promising tool for CRT candidates. The non-invasive ventricular activation maps acquired by ECGi have been primarily explored for the diagnosis and guidance of therapy in patients with atrial or ventricular tachyarrhythmia. However, the accuracy of the system in this field is lacking and needs further improvement before considering a clinical application. On the other hand, its use for patient selection for CRT is encouraging. In this review, we introduce the technical considerations and we describe how ECGi can precisely characterize ventricular activation, especially in patients with left bundle branch block, thus identifying the electrical substrate responsive to CRT.

NEXN Gene in Cardiomyopathies and Sudden Cardiac Deaths: Prevalence, Phenotypic Expression, and Prognosis.

BACKGROUND: Few clinical data are available on NEXN mutation carriers, and the gene's involvement in cardiomyopathies or sudden death has not been fully established. Our objectives were to assess the prevalence of putative pathogenic variants in NEXN and to describe the phenotype and prognosis of patients carrying the variants. METHODS: DNA samples from consecutive patients with cardiomyopathy or sudden cardiac death/sudden infant death syndrome/idiopathic ventricular fibrillation were sequenced with a custom panel of genes. Index cases carrying at least one putative pathogenic variant in the NEXN gene were selected. RESULTS: Of the 9516 index patients sequenced, 31 were carriers of a putative pathogenic variant in NEXN only, including 2 with double variants and 29 with a single variant. Of the 29 unrelated probands with a single variant (16 males; median age at diagnosis, 32.0 [26.0-49.0] years), 21 presented with dilated cardiomyopathy (prevalence, 0.33%), and 3 presented with hypertrophic cardiomyopathy (prevalence, 0.14%). Three patients had idiopathic ventricular fibrillation, and there were 2 cases of sudden infant death syndrome (prevalence, 0.46%). For patients with dilated cardiomyopathy, the median left ventricle ejection fraction was 37.5% (26.25-50.0) at diagnosis and improved with treatment in 13 (61.9%). Over a median follow-up period of 6.0 years, we recorded 3 severe arrhythmic events and 2 severe hemodynamic events. CONCLUSIONS: Putative pathogenic NEXN variants were mainly associated with dilated cardiomyopathy; in these individuals, the prognosis appeared to be relatively good. However, severe and early onset phenotypes were also observed-especially in patients with double NEXN variants. We also detected NEXN variants in patients with hypertrophic cardiomyopathy and sudden infant death syndrome/idiopathic ventricular fibrillation, although a causal link could not be established.

Left atrial appendage closure in very elderly patients in the French National Registry.

OBJECTIVE: Left atrial appendage closure (LAAC) is recommended to decrease the stroke risk in patients with atrial fibrillation and contraindications to anticoagulation. However, age-stratified data are scarce. The aim of this study was to provide information on the safety and efficacy of LAAC, with emphasis on the oldest patients. METHODS: A nationwide, prospective, multicentre, observational registry was established by 53 French cardiology centres in 2018-2021. The composite primary endpoint included ischaemic stroke, systemic embolism, and unexplained or cardiovascular death. Separate analyses were done in the groups <80 years and ≥80 years. RESULTS: Among the 1053 patients included, median age was 79.7 (73.6-84.3) years; 512 patients (48.6%) were aged ≥80 years. Procedure-related serious adverse events were non-significantly more common in octogenarians (7.0% vs 4.4% in patients aged <80 years, respectively; p=0.07). Despite a higher mean CHA2DS2-VASc score in octogenarians, the rate of thromboembolic events during the study was similar in both groups (3.0 vs 3.1/100 patient-years; p=0.85). By contrast, all-cause mortality was significantly higher in octogenarians (15.3 vs 10.1/100 patient-years, p<0.015), due to a higher rate of non-cardiovascular deaths (8.2 vs 4.9/100 patient-years, p=0.034). The rate of the primary endpoint was 8.1/100 patient-years overall with no statistically significant difference between age groups (9.4 and 7.0/100 patient-years; p=0.19). CONCLUSION: Despite a higher mean CHA2DS2-VASc score in octogenarians, the rate of thromboembolic events after LAAC in this age group was similar to that in patients aged <80 years. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Registry (NCT03434015).

Transfemoral versus trans-subclavian access in transcatheter aortic valve implantation using self-expandable valve: A propensity-matched comparison.

BACKGROUND: Transcatheter aortic valve implantation is unfeasible for 10-15% of patients using the conventional transfemoral approach. Other alternative approaches, such as the subclavian approach, have emerged, with no clear recommendation indicating the superiority of one technique over another. AIM: To compare the 1-month mortality and postprocedural outcomes of patients undergoing transcatheter aortic valve implantation using a self-expandable valve via transfemoral and subclavian access. METHODS: This was a retrospective single-centre study including 1496 patients who underwent transcatheter aortic valve implantation between January 2016 and December 2020 at Clermont-Ferrand University Hospital, France. Propensity score matching was used to compare transfemoral and subclavian access. RESULTS: After building two propensity score-matched groups of 221 patients each with either access route (total n=442), baseline characteristics were similar. The procedure duration was significantly longer in the subclavian access group (53 [45-64] versus 60 [51-72] minutes; P<0.001), but with a lower amount of contrast agent (138 [118-165] versus 123 [105-150] mL; P<0.001), fluoroscopy time (11.2 [9-14] versus 9.9 [7-12] minutes; P<0.001) and radiation dose (397 [264-620] versus 321 [217-485] mGy; P<0.001). No significant difference was observed concerning 1-month mortality (odds ratio 1.62, 95% confidence interval 0.52-5.03; P=0.39) or periprocedural complications. Follow-up at 1 year confirmed no difference in longer-term mortality (hazard ratio 0.78, 95% confidence interval 0.52-5.03; P=0.43). CONCLUSIONS: The subclavian approach provides similar results to the transfemoral approach in terms of mortality, efficacy and safety; it is a reasonable and effective alternative when the reference transfemoral approach is impossible or seems complex.

T-Wave Oversensing with Contemporary Implantable Cardioverter-Defibrillators.

BACKGROUND: Implantable cardioverter-defibrillators (ICDs) need to reliably detect ventricular tachycardia (VT) and ventricular fibrillation (VF) while avoiding T-wave oversensing (TWOS), which is associated with a risk of inappropriate therapies. The incidence of TWOS with endovascular ICDs appears to differ between manufacturers. OBJECTIVES: We aimed to evaluate the incidence and clinical consequences of TWOS with contemporary Medtronic and Boston Scientific ICDs. METHODS: Consecutive patients implanted with a recent Medtronic or Boston Scientific ICD and remotely monitored at three French centers were included. All transmitted EGMs labelled as VF, VT, non-sustained VT (NSVT), or ventricular oversensing (Medtronic) were screened for TWOS. RESULTS: Among 7589 transmitted episodes from 674 patients with a Boston Scientific ICD, we did not identify a single case of TWOS. Among 16,790 transmitted episodes from 1733 patients with a Medtronic ICD, we identified 60 patients (3.4%) with at least one episode of TWOS. In 46 patients, TWOS was intermittent (NSVT episodes). In the remaining 14 patients, TWOS resulted in 60 sustained episodes (completed counters). No inappropriate therapies were delivered in 12 of these patients because no therapies were programmed (in monitor zones, 11 episodes) or because therapies were inhibited by the morphology discriminator (Wavelet, 19 episodes) or by the anti-TWOS algorithm (26 episodes). Two patients received inappropriate therapies due to TWOS (0.1% of patients with Medtronic ICDs). CONCLUSION: On review of 24,379 transmitted episodes from 2407 patients with endovascular ICDs, we found no case of TWOS with Boston Scientific devices, whereas TWOS was not uncommon with Medtronic devices. However, the risk of inappropriate therapy with Medtronic ICDs was very low (0.1%) due to the often intermittent nature of this phenomenon, the morphology discriminator, and the anti-TWOS algorithm.

Remote management of worsening heart failure to avoid hospitalization in a real-world setting.

AIMS: From a patient and health system perspective, managing worsening heart failure (WHF) as an outpatient has become a priority. Remote management allows early detection of WHF, enabling timely intervention with the aim of preventing hospitalization. The objective of the study was to evaluate the feasibility and safety of remotely managing WHF events using a multiparametric platform. METHODS AND RESULTS: All patients enrolled in the heart failure remote management programme of the Bordeaux University Hospital Telemedicine Center between 1 January and 31 December 2021 were included in the study. Follow-up data were collected until 1 March 2022. Inclusion criteria were chronic heart failure (HF) with New York Heart Association ≥II symptoms and an elevated B-type natriuretic peptide (BNP > 100 pg/mL or N-terminal-pro-BNP > 1000 pg/mL). Patient assessments were performed remotely and included measurements of body weight, blood pressure, heart rate, symptoms, biochemical parameters, and data from cardiac implantable electronic devices when available. In total, 161 patients (71 ± 11 years old, 79% male) were followed for a mean of 291 ± 66 days with a mean adherence to the remote monitoring system of 80 ± 20%. Over this period, 52 (32.3%) patients had 105 WHF events, of which 66 (63%) were successfully managed remotely, the remaining requiring hospitalization. Freedom from WHF events and hospitalization at 300 days were 66% and 85%, respectively (P < 0.001 for the difference). Increased level of BNP was associated with an increased risk of WHF event [hazard ratio (HR) per unit increase in BNP: 1.001; 95% confidence interval (CI) 1-1.002; P = 0.001] and hospitalization (HR 1.002; 95% CI 1.002-1.003; P = 0.002). A decrease in the level of glomerular filtration rate was associated with an increased risk of hospitalization (HR per unit decrease in estimated glomerular filtration rate: 0.946; 95% CI 0.906-0.989; P = 0.014). WHF event recurrence and (re)hospitalization rates at 1-month were similar among patients managed remotely (18% and 12%, respectively) and those requiring hospitalization (21% and 10%, respectively). Iatrogenic complications occurred more often during hospitalization than remote management (26% vs. 3%, P < 0.001). CONCLUSIONS: Our study suggests that remote management of WHF events based on a multiparametric approach led by a telemedical centre is feasible and safe. Adopting such a strategy for patients with chronic HF could reduce HF-related hospitalizations with expected benefits for patients, care providers, and health care systems.

Role of aldosterone in mid- and long-term left ventricular remodelling after acute myocardial infarction: The REMI study.

AIMS: Whether aldosterone levels after myocardial infarction (MI) are associated with mid- and long-term left ventricular (LV) remodelling in the era of systematic use of renin-angiotensin system inhibitors is uncertain. We prospectively investigated the relationship between aldosterone levels and mid- and long-term LV remodelling in patients with acute MI. METHODS AND RESULTS: Plasma aldosterone was measured in 119 patients successfully treated by primary percutaneous coronary angioplasty for a first acute ST-elevation MI (STEMI) 2-4 days after the acute event. LV volumes were assessed by cardiac magnetic resonance (CMR) and transthoracic echocardiography (TTE) in the same timeframe and 6 months later. LV assessment was repeated by TTE 3-9 years after MI (n = 80). The median aldosterone level at baseline was 23.1 [16.8; 33.1] pg/ml. In the multivariable model, higher post-MI aldosterone concentration was significantly associated with more pronounced increase in LV end-diastolic volume index (TTE: ß ± standard error [SE]: 0.113 ± 0.046, p = 0.015; CMR: ß ± SE: 0.098 ± 0.040, p = 0.015) and LV end-systolic volume index (TTE: ß ± SE: 0.083 ± 0.030, p = 0.008; CMR: ß ± SE: 0.064 ± 0.032, p = 0.048) at 6-month follow-up, regardless of the method of assessment. This result was consistent also in patients with a LV ejection fraction (LVEF) >40%. The association between baseline plasma aldosterone and adverse LV remodelling did not persist at the 3-9-year follow-up evaluation. CONCLUSION: Aldosterone concentration in the acute phase was associated with adverse LV remodelling in the medium term, even in the subgroup of patients with LVEF >40%, suggesting a potential role of the mineralocorticoid system in post-MI adverse remodelling. Plasma aldosterone was no longer associated with LV remodelling in the long term (NCT01109225).

Left Atrial Appendage Occlusion Under Miniaturized Transesophageal Echocardiographic Guidance and Conscious Sedation: Multicenter European Experience.

BACKGROUND: Left atrial appendage occlusion (LAAO) procedures are widely guided by standard transesophageal echocardiography (TEE) probes, requiring general anesthesia in most patients. The use of miniaturized TEE probes allows for LAAO guidance under local anesthesia and offers an attractive imaging alternative to standard TEE probes. OBJECTIVES: The aim of this study was to assess the safety and efficacy of miniaturized TEE probes for procedural guidance of LAAO. METHODS: Multicenter retrospective observational study of LAAO procedures performed under miniaturized TEE guidance and conscious sedation. The primary efficacy endpoint was technical success. The secondary efficacy endpoint was procedural success (technical success without major periprocedural complications). The safety outcome was a composite of major periprocedural complications. RESULTS: A total of 546 consecutive LAAO procedures were performed in 5 European centers. Technical success was achieved in 534 (98.0%) patients. Sixteen major periprocedural complications occurred in 15 (2.9%) patients, yielding a procedural success rate of 97.0%. Conversion to general anesthesia was required in 4 (0.7%) patients. Short-term imaging follow-up was available in 422 patients with an incidence of major (>5 mm) TEE-detected residual leaks of 0.7%, complete LAA occlusion of 82.2% on cardiac computed tomography, and device-related thrombus of 5%. As compared with procedural 2-dimensional imaging for device sizing, preprocedural assessment by 3-dimensional imaging resulted in improved technical success (100% vs 95.0%; P < 0.001). CONCLUSIONS: LAAO under conscious sedation and miniaturized TEE guidance is safe and feasible with a high rate of technical success and a low rate of periprocedural complications.

Subcutaneous Implantable Cardioverter-Defibrillators in Patients With Congenital Heart Disease.

BACKGROUND: Very few data have been published on the use of subcutaneous implantable cardioverter-defibrillators (S-ICDs) in patients with congenital heart disease (CHD). OBJECTIVES: The aim of this study was to analyze outcomes associated with S-ICDs in patients with CHD. METHODS: This nationwide French cohort including all patients with an S-ICD was initiated in 2020 by the French Institute of Health and Medical Research. Characteristics at implantation and outcomes were analyzed in patients with CHD. RESULTS: From October 12, 2012, to December 31, 2019, among 4,924 patients receiving an S-ICD implant in 150 centers, 101 (2.1%) had CHD. Tetralogy of Fallot, univentricular heart, and dextro-transposition of the great arteries represented almost one-half of the population. Patients with CHD were significantly younger (age 37.1 ± 15.4 years vs 50.1 ± 14.9 years; P < 0.001), more frequently female (37.6% vs 23.0%; P < 0.001), more likely to receive an S-ICD for secondary prevention (72.3% vs 35.9%; P < 0.001), and less likely to have severe systolic dysfunction of the systemic ventricle (28.1% vs 53.1%; P < 0.001). Over a mean follow-up period of 1.9 years, 16 (15.8%) patients with CHD received at least 1 appropriate shock, with all shocks successfully terminating the ventricular arrhythmia. The crude risk of appropriate S-ICD shock was twice as high in patients with CHD compared with non-CHD patients (annual incidences of 9.0% vs 4.4%; HR: 2.1; 95% CI: 1.3-3.4); however, this association was no longer significant after propensity matching (especially considering S-ICD indication, P = 0.12). The burden of all complications (HR: 1.2; 95% CI: 0.7-2.1; P = 0.4) and inappropriate shocks (HR: 0.9; 95% CI: 0.4-2.0; P = 0.9) was comparable in both groups. CONCLUSIONS: In this nationwide study, patients with CHD represented 2% of all S-ICD implantations. Our findings emphasize the effectiveness and safety of S-ICD in this particularly high-risk population. (S-ICD French Cohort Study [HONEST]; NCT05302115).

Artificial intelligence for detection of ventricular oversensing: Machine learning approaches for noise detection within nonsustained ventricular tachycardia episodes remotely transmitted by pacemakers and implantable cardioverter-defibrillators.

BACKGROUND: Pacemakers (PMs) and implantable cardioverter-defibrillators (ICDs) increasingly automatically record and remotely transmit nonsustained ventricular tachycardia (NSVT) episodes, which may reveal ventricular oversensing. OBJECTIVES: We aimed to develop and validate a machine learning algorithm that accurately classifies NSVT episodes transmitted by PMs and ICDs in order to lighten health care workload burden and improve patient safety. METHODS: PMs or ICDs (Boston Scientific, St Paul, MN) from 4 French hospitals with ≥1 transmitted NSVT episode were split into 3 subgroups: training set, validation set, and test set. Each NSVT episode was labeled as either physiological or nonphysiological. Four machine learning algorithms-2DTF-CNN, 2D-DenseNet, 2DTF-VGG, and 1D-AgResNet-were developed using training and validation data sets. Accuracies of the classifiers were compared with an analysis of the remote monitoring team of the Bordeaux University Hospital using F2 scores (favoring sensitivity over predictive positive value) using an independent test set. RESULTS: A total of 807 devices transmitted 10,471 NSVT recordings (82% ICD; 18% PM), of which 87 devices (10.8%) transmitted 544 NSVT recordings with nonphysiological signals. The classification by the remote monitoring team resulted in an F2 score of 0.932 (sensitivity 95%; specificity 99%) The 4 machine learning algorithms showed high and comparable F2 scores (2DTF-CNN: 0.914; 2D-DenseNet: 0.906; 2DTF-VGG: 0.863; 1D-AgResNet: 0.791), and only 1D-AgResNet had significantly different labeling from that of the remote monitoring team. CONCLUSION: Machine learning algorithms were accurate in detecting nonphysiological signals within electrograms transmitted by PMs and ICDs. An artificial intelligence approach may render remote monitoring less resourceful and improve patient safety.

Insertable cardiac monitor with a long sensing vector: Impact of obesity on sensing quality and safety.

Background: Fat layers in obese patients can impair R-wave detection and diagnostic performance of a subcutaneous insertable cardiac monitor (ICM). We compared safety and ICM sensing quality between obese patients [body mass index (BMI) ≥ 30 kg/m2] and normal-weight controls (BMI <30 kg/m2) in terms of R-wave amplitude and time in noise mode (noise burden) detected by a long-sensing-vector ICM. Materials and methods: Patients from two multicentre, non-randomized clinical registries are included in the present analysis on January 31, 2022 (data freeze), if the follow-up period was at least 90 days after ICM insertion, including daily remote monitoring. The R-wave amplitudes and daily noise burden averaged intraindividually for days 61-90 and days 1-90, respectively, were compared between obese patients (n = 104) and unmatched (n = 268) and a nearest-neighbour propensity score (PS) matched (n = 69) normal-weight controls. Results: The average R-wave amplitude was significantly lower in obese (median 0.46 mV) than in normal-weight unmatched (0.70 mV, P < 0.0001) or PS-matched (0.60 mV, P = 0.003) patients. The median noise burden was 1.0% in obese patients, which was not significantly higher than in unmatched (0.7%; P = 0.056) or PS-matched (0.8%; P = 0.133) controls. The rate of adverse device effects during the first 90 days did not differ significantly between groups. Conclusion: Although increased BMI was associated with reduced signal amplitude, also in obese patients the median R-wave amplitude was >0.3 mV, a value which is generally accepted as the minimum level for adequate R-wave detection. The noise burden and adverse event rates did not differ significantly between obese and normal-weight patients.Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04075084 and NCT04198220.

Diagnostic yield of an insertable cardiac monitor in a large patient population.

Background: Insertable cardiac monitors (ICMs) are increasingly used for cardiac rhythm diagnosis with expanding indications. Little has been reported about their use and efficacy. Objective: The study sought to evaluate the clinical utility of a novel ICM (Biotronik BIOMONITOR III) including the time to diagnosis in unselected patients with different ICM indications. Methods: Patients from 2 prospective clinical studies were included to determine the diagnostic yield of the ICM. The primary endpoint was time to clinical diagnosis per implant indication or to the first change in atrial fibrillation (AF) therapy. Results: A total of 632 patients were included with a mean follow-up of 233 ± 168 days. Of 384 patients with (pre)syncope, 34.2% had a diagnosis at 1 year. The most frequent therapy was permanent pacemaker implantation. Of 133 patients with cryptogenic stroke, 16.6% had an AF diagnosis at 1 year, resulting in oral anticoagulation. Of 49 patients with an indication for AF monitoring, 41.0% had a relevant change in AF therapy based on ICM data at 1 year. Of 66 patients with other indications, 35.4% received a rhythm diagnosis at 1 year. Moreover, 6.5% of the cohort had additional diagnoses: 26 of 384 patients with syncope, 8 of 133 patients with cryptogenic stroke, and 7 of 49 patients with AF monitoring. Conclusion: In a large unselected patient population with heterogeneous ICM indications, the primary endpoint of rhythm diagnosis was achieved in ∼1 in 4, and additional clinically relevant findings was achieved in 6.5% of patients at short-term follow-up.

Post-Dilatation of New-Generation Self-Expandable Transcatheter Aortic Valves Does Not Increase Atrioventricular Conduction Abnormalities.

The impact that post-dilatation has on the risk of experiencing conduction disorders after post-transcatheter aortic valve replacement with self-expanding valves (SE-TAVR) is unclear. We compared the rate of developing an atrioventricular (AV) high-grade conduction disorder and permanent pacemaker implantation (PPI) in post-TAVR patients undergoing post-dilatation. We enrolled patients with severe symptomatic calcified aortic stenosis (CAS) who were undergoing SE-TAVR between 1 January 2016, and 19 April 2019 at a single French center. Of the 532 patients treated with SE-TAVR, 417 subjects (78.4%) received Corevalve Evolute R and 115 subjects (21.6%) received the latest-generation Corevalve Evolute Pro valve. In total, 104/532 patients (19.5%; 21.6% with Evolute R vs. 12.2% with Evolute Pro, p = 0.024) required post-dilatation. Evolut R was associated with an increased risk of post-dilatation (odds ratio 2.1 (1.01-4.33, p = 0.046)). We did not observe any post-dilatation increases in AV or in intra- and interventricular conduction disorders. In total, 26.1% of participants needed PPI within the first 30 post-procedure days (p = 0.449). Post-dilatation was not associated with a higher PPI risk (subdistribution hazard ratio 1.033 (0.726-1.471); p = 0.857). No significant differences existed between the groups in terms of one-year mortality (10.3%; p = 0.507). Post-dilatation in SE-TAVR did not increase the rate of electrical conduction disorders and PPI in the early implantation phase. The latest generation of SE-TAVR valves was associated with less need for post-dilatation.

A leadless pacemaker in the real-world setting: Patient profile and performance over time.

Background: While prior Micra trials demonstrated a high implant success rate and favorable safety and efficacy results, changes in implant populations and safety over time is not well studied. The objective of this analysis was to report the performance of Micra in European and Middle Eastern patients and compare to the Micra Investigational Device Exemption (IDE) and Micra Post Approval Registry (PAR) studies. Methods: The prospective, single-arm Micra Acute Performance European and Middle Eastern (MAP EMEA) registry was designed to further study the performance of Micra in patients from EMEA. The primary endpoint was to characterize acute (30-day) major complications. Electrical performance was analyzed. The major complication rate through 12 months was compared with the IDE and PAR studies. Results: The MAP EMEA cohort (n = 928 patients) had an implant success rate of 99.9% and were followed for an average of 9.7 ± 6.5 months. Compared to prior studies, MAP EMEA patients were more likely to have undergone dialysis and have a condition which precluded the use of a transvenous pacemaker (p < .001). Within 30 days of implantation, the MAP EMEA cohort had a major complication rate of 2.59%. Mean pacing thresholds were low and stable through 12 months (0.61 ± 0.40 V at 0.24 ms at implant and 12 months). Through 12 months post-implantation, the major complication rate for MAP EMEA was not significantly different from IDE (p = .56) or PAR (p = .79). Conclusion: Despite patient differences over time, the Micra leadless pacemaker was implanted with a high success rate and low complication rate, in-line with prior reports.

Incidence and management of atrioventricular conduction disorders in new-onset left bundle branch block after TAVI: A prospective multicenter study.

BACKGROUND: New-onset left bundle branch block (LBBB) is one of the most frequent complications after transcatheter aortic valve implantation (TAVI) and is associated with delayed high degree atrioventricular (AV) block. OBJECTIVES: The objectives of this study were to determine the incidence of AV block in such a population and to assess the performance and safety of a risk stratification algorithm on the basis of electrophysiology study (EPS) followed by implantation of a pacemaker or implantable loop recorder (ILR). METHODS: This was a prospective open-label study with 12-month follow-up. From June 8, 2015, to November 8, 2018, 183 TAVI recipients (mean age 82.3 ± 5.9 years) were included at 10 centers. New-onset LBBB after TAVI persisting for >24 hours was assessed by electrophysiology study during initial hospitalization. High-risk patients (His-ventricle interval ≥70 ms) were implanted with a dual-chamber pacemaker recording AV conduction disturbance episodes. Patients at lower risk were implanted with an ILR with automatic remote monitoring. RESULTS: A high-grade AV conduction disorder was identified in 56 patients (30.6%) at 12 months. Four subjects were symptomatic, all in the ILR group. No complications were associated with the stratification procedure. Patients with His-ventricle interval ≥70 ms displayed more high-grade AV conduction disorders (53.2% [25 of 47] vs 22.8% [31 of 136]; P < .001). In a multivariate analysis, His-ventricle interval ≥70 ms was independently associated with the occurrence of a high-grade conduction disorder (subdistribution hazard ratio 2.4; 95% confidence interval 1.2-4.8; P = .010). CONCLUSION: New-onset LBBB after TAVI was associated with high rates of high-grade AV conduction disturbances. The stratification algorithm provided safe and valuable aid to management decisions and reliable guidance on pacemaker implantation.

Ionized Magnesium: Interpretation and Interest in Atrial Fibrillation.

BACKGROUND: Magnesium (Mg) is often used to manage de novo atrial fibrillation (AF) in the emergency department (ED) and intensive care unit (ICU). Point of care measurement of ionized magnesium (iMg) allows a rapid identification of patients with impaired magnesium status, however, unlike ionized calcium, the interpretation of iMg is not entirely understood. Thus, we evaluated iMg reference values, correlation between iMg and plasmatic magnesium (pMg), and the impact of pH and albumin variations on iMg levels. Secondary objectives were to assess the incidence of hypomagnesemia in de novo AF. METHODS: A total of 236 emergency department and intensive care unit patients with de novo AF, and 198 control patients were included. Reference values were determined in the control population. Correlation and concordance between iMg and pMg were studied using calcium (ionized and plasmatic) as a control in the whole study population. The impact of albumin and pH was assessed in the discordant iMg and pMg values. Lastly, we assessed the incidence of ionized hypomagnesemia (hypoMg) among de novo AF. RESULTS: The reference range values established in our study for iMg were: 0.48-0.65 mmol/L (the manufacturers were: 0.45-0.60 mmol/L). A strong correlation was observed between pMg and iMg (r = 0.85), but, unlike for calcium values, there was no significant impact of pH and albumin in iMg/pMg interpretation. The incidence of hypoMg among de novo AF patients was 8.5% (12.7% using our ranges). When using our ranges, we found a significant link (p = 0.01) between hyopMg and hypokalemia. CONCLUSION: We highlight the need for more accurate reference range values of iMg. Furthermore, our results suggest that blood Mg content is not identical to that of calcium. The incidence of ionized hypomagnesemia among de novo AF patients in our study is 8.5%.

Implantation of a leadless pacemaker in young adults.

AIMS: Leadless pacing has emerged as an alternative to conventional transvenous pacemakers to mitigate the risks of pocket- and lead-related complications but its use remains controversial in young adults mostly because experience in this patient population is limited. We sought to examine the feasibility and safety of implanting leadless single chamber pacemakers in young adults. METHODS: This multicenter, retrospective, observational study sought to evaluate the safety, efficacy, and electrical performance of the Micra VR Transcatheter Pacemaker System (Medtronic) in patients between 18 and 40 years who underwent implantation of a leadless pacemaker for any indication at the university medical centers of Bordeaux, Clermont-Ferrand, Toulouse, and Tours (France), between 2015 and 2021. The primary safety endpoint was freedom from system-related or procedure-related major complications at 6 months. The primary efficacy endpoint was the combination of a low (≤2 V) and stable (increase within 1.5 V) pacing capture threshold at 6 months. RESULTS: Leadless pacemaker implantation was successful in all 35 patients. At 6 months, safety endpoint was met for 35 (100%) and efficacy endpoint for 34 (97%) patients. During a follow-up of 26 ± 15 months (range: 6-60 months), Safety endpoint remained 100% and efficacy endpoint was 94%. Leadless pacemaker retrieval was not required in any patient. Approximately one-third of patients (n = 13, 37%) had >40% ventricular pacing burdens at 1 year, including all 10 patients with a complete AV block but also 3 patients with normal AV conduction during implantation. One patient reported symptoms of pacemaker syndrome which was confirmed using Holter recording and successfully treated using reprogramming. CONCLUSION: In this observational study, leadless pacemakers demonstrated favorable short- and intermediate-term safety and effectiveness in young adults.

Rapid ventricular tachycardia in patients with tetralogy of Fallot and implantable cardioverter-defibrillator: Insights from the DAI-T4F nationwide registry.

BACKGROUND: In repaired tetralogy of Fallot (TOF), little is known about characteristics of patients with rapid ventricular tachycardia (VT). Also, whether patients with a first episode of nonrapid VT may subsequently develop rapid VT or ventricular fibrillation (VF) has not been addressed. OBJECTIVES: The objectives of this study were to compare patients with rapid VT/VF with those with nonrapid VT and to assess the evolution of VT cycle lengths (VTCLs) overtime. METHODS: Data were analyzed from a nationwide registry including all patients with TOF and implantable cardioverter-defibrillator (ICD) since 2000. Patients with ≥1 VT episode with VTCL ≤250 ms (240 beats/min) formed the rapid VT/VF group. RESULTS: Of 144 patients (mean age 42.0 ± 12.7 years; 104 [72%] men), 61 (42%) had at least 1 VT/VF episode, including 28 patients with rapid VT/VF (46%), during a median follow-up of 6.3 years (interquartile range 2.2-10.3 years). Compared with patients in the nonrapid VT group, those in the rapid VT/VF group were significantly younger at ICD implantation (35.2 ± 12.6 years vs 41.5 ± 11.2 years; P = .04), had more frequently a history of cardiac arrest (8 [29%] vs 2 [6%]; P = .02), less frequently a history of atrial arrhythmia (11 [42%] vs 22 [69%]; P = .004), and higher right ventricular ejection fraction (43.3% ± 10.3% vs 36.6% ± 11.2%; P = .04). The median VTCL of VT/VF episodes was 325 ms (interquartile range 235-429 ms). None of the patients with a first documented nonrapid VT episode had rapid VT/VF during follow-up. CONCLUSION: Patients with TOF and rapid VT/VF had distinct clinical characteristics. The relatively low variation of VTCL over time suggests a room for catheter ablation without a backup ICD in selected patients with well-tolerated VT.

Sex Differences in Outcomes of Tetralogy of Fallot Patients With Implantable Cardioverter-Defibrillators.

BACKGROUND: Women with congenital heart disease at high risk for sudden cardiac death have been poorly studied thus far. OBJECTIVES: The aim of this study was to assess sex-related differences in patients with tetralogy of Fallot (TOF) and implantable cardioverter-defibrillators (ICDs). METHODS: Data were analyzed from the DAI-T4F (French National Registry of Patients With Tetralogy of Fallot and Implantable Cardioverter Defibrillator) cohort study, which has prospectively enrolled all patients with TOF with ICDs in France since 2010. Clinical events were centrally adjudicated by a blinded committee. RESULTS: A total of 165 patients (mean age 42.2 ± 13.3 years) were enrolled from 40 centers, including 49 women (29.7%). Among the 9,692 patients with TOF recorded in the national database, the proportion of women with ICDs was estimated to be 1.1% (95% CI: 0.8%-1.5%) vs 2.2% (95% CI: 1.8%-2.6%) in men (P < 0.001). The clinical profiles of patients at implantation, including the number of risk factors for ventricular arrhythmias, were similar between women and men. During a median follow-up period of 6.8 years (IQR: 2.5-11.4 years), 78 patients (47.3%) received at least 1 appropriate ICD therapy, without significant difference in annual incidences between women (12.1%) and men (9.9%) (HR: 1.22; 95% CI: 0.76-1.97; P = 0.40). The risk for overall ICD-related complications was similar in women and men (HR: 1.33; 95% CI: 0.81-2.19; P = 0.30), with 24 women (49.0%) experiencing at least 1 complication. CONCLUSIONS: Our findings suggest that women with TOF at high risk for sudden cardiac death have similar benefit/risk balance from ICD therapy compared with men. Whether ICD therapy is equally offered to at-risk women vs men warrants further evaluation in TOF as well as in other congenital heart disease populations. (French National Registry of Patients With Tetralogy of Fallot and Implantable Cardioverter Defibrillator [DAI-T4F]; NCT03837574).