Using technology to improve reconnection to remote monitoring in cardiac implantable electronic device patients.

Background: Remote monitoring (RM) of cardiac implantable electronic device (CIED) patients is now considered standard of care. However, a fundamental requirement of RM is continuous connectivity between the patient's implanted device and the CIED manufacturer's central server. This study examined the rate of RM disconnections in CIED recipients and the impact of short message service (SMS) to facilitate reconnections. Methods: Using a platform that collects RM data from CIED manufacturers, we retrospectively examined the disconnection and reconnection events in 6085 patients from 20 medical centers. Each medical center reported their usual practice regarding RM disconnections, which consisted of either an automatic SMS from the platform to patients who were disconnected for 2 weeks or the standard of care (SC) of a phone call to patients. Results: During a 1-year period, 43% of patients had at least 1 disconnection. Half of these patients experienced multiple disconnections. The use of SMS reduced the time to reconnection by 43% in comparison to SC. The median time to reconnect a disconnected patient was 11.0 [3.2, 29.0] days for SC vs 6.3 [1.3, 22.0] days for SMS (P < .0001). Furthermore, there was a high rate of reconnections within the first 48 hours of the SMS message, which was nearly double that in the SC arm. Conclusion: This study demonstrates the feasibility of an automatic system to deliver an SMS to patients with a disconnected CIED to facilitate early reconnection to RM.

Filtering of remote monitoring alerts transmitted by cardiac implantable electronic devices and reclassification of atrial fibrillation events by a new algorithm.

Background: Cardiac implantable electronic devices (CIEDs) are an important means of atrial fibrillation (AF) detection. However, the AF burden measurements and notifications transmitted by CIEDs are not directly related to the clinical classification of paroxysmal, persistent, or permanent AF. Moreover, AF alerts are the most frequent form of notification, imposing a time-consuming review on caregivers. Objective: The purpose of this study was to compare the incidence of standard AF burden-related notifications in remotely monitored (RM) patients with the incidence of events detected after filtering by a new proprietary algorithm implementing the standard European Society of Cardiology classification of AF. Methods: Between 2017 and 2022, all RM patients with daily AF burden measurements available for ≥30 days and ≥1 AF burden-related alerts were enrolled at 68 medical centers. The incidence of CIED-transmitted alerts was compared to that of AF episodes detected by a new proprietary algorithm and classified as "first recorded episode of AF", "paroxysmal AF", "increased paroxysmal AF", "persistent AF", or "end of persistent AF back to paroxysmal AF or back to sinus rhythm." Results: Between January 2017 and September 2022, this retrospective study analyzed data from 4162 recipients of an Abbott, Biotronik, Boston Scientific, or Medtronic CIED, RM over mean follow-up of 605 ± 386 days. The algorithm broke down 67,883 AF burden-related alerts into 9728 (14.3%) clinically relevant AF events. Conclusion: A new AF alert algorithm successfully identified clinically significant AF events in RM CIED recipients and would markedly limit the total number of transmitted alerts that require review by caregivers.

CRT-D replacement strategy: results of the BioCONTINUE study.

BACKGROUND: In patients with cardiac resynchronization therapy defibrillators (CRT-Ds), the need for implantable cardioverter-defibrillator (ICD) back-up may be questionable at time of CRT-D replacement (REP) if ICD implant criteria are no longer met due to an improved left ventricular ejection fraction (LVEF) and if no major ventricular arrhythmic event (VAE) occurred during the CRT-D lifetime. The aim of our study was to assess the relevance of ICD back-up and predictors of VAE after REP in primary prevention CRT-D patients. METHODS: The prospective, observational, international BioCONTINUE study investigated the rate of patients with at least 1 sustained VAE (sVAE) post-REP and searched for predictive factors of sVAE. RESULTS: Two hundred seventy-six patients (70 ± 10 years, 77% men, mean LVEF 40.6 ± 12.6%) were followed for 28.4 ± 10.2 months. The rate of patients with sVAE was 8.3%, 10.3%, and 21.2% at 1, 2, and 4 years post-REP. Patients without persistent ICD indication at REP still had a sVAE rate of 5.7% (95% CI 2.3-11.5%) at 2 years. In multivariate analysis, predictive factors of subsequent sVAE were (i) persistent ICD indication (hazard ratio (HR) 3.6; 95% CI 1.6-8.3; p = 0.003); (ii) 64-72 years of age as compared to ≥ 79 years (HR 3.7; 95% CI 1.4-9.7; p = 0.008); and (iii) ischemic heart disease (HR 4.4; 95% CI 2.1-9.3; p < 0.0001). CONCLUSIONS: The risk of sVAE (21.2% at 4 years post-REP) depends on age, ischemic heart disease, and ICD indication at the time of REP. A non-trivial risk of sVAE remains in patients without persistent ICD indication. CLINICAL TRIAL REGISTRATION: NCT02323503.

Improved diagnostic performance of insertable cardiac monitors by an artificial intelligence-based algorithm.

AIMS: The increasing use of insertable cardiac monitors (ICM) produces a high rate of false positive (FP) diagnoses. Their verification results in a high workload for caregivers. We evaluated the performance of an artificial intelligence (AI)-based ILR-ECG Analyzer™ (ILR-ECG-A). This machine-learning algorithm reclassifies ICM-transmitted events to minimize the rate of FP diagnoses, while preserving device sensitivity. METHODS AND RESULTS: We selected 546 recipients of ICM followed by the Implicity™ monitoring platform. To avoid clusterization, a single episode per ICM abnormal diagnosis (e.g. asystole, bradycardia, atrial tachycardia (AT)/atrial fibrillation (AF), ventricular tachycardia, artefact) was selected per patient, and analyzed by the ILR-ECG-A, applying the same diagnoses as the ICM. All episodes were reviewed by an adjudication committee (AC) and the results were compared. Among 879 episodes classified as abnormal by the ICM, 80 (9.1%) were adjudicated as 'Artefacts', 283 (32.2%) as FP, and 516 (58.7%) as 'abnormal' by the AC. The algorithm reclassified 215 of the 283 FP as normal (76.0%), and confirmed 509 of the 516 episodes as abnormal (98.6%). Seven undiagnosed false negatives were adjudicated as AT or non-specific abnormality. The overall diagnostic specificity was 76.0% and the sensitivity was 98.6%. CONCLUSION: The new AI-based ILR-ECG-A lowered the rate of FP ICM diagnoses significantly while retaining a > 98% sensitivity. This will likely alleviate considerably the clinical burden represented by the review of ICM events.

A Visual Approach to Measure Cloth-Body and Cloth-Cloth Friction.

Measuring contact friction in soft-bodies usually requires a specialised physics bench and a tedious acquisition protocol. This makes the prospect of a purely non-invasive, video-based measurement technique particularly attractive. Previous works have shown that such a video-based estimation is feasible for material parameters using deep learning, but this has never been applied to the friction estimation problem which results in even more subtle visual variations. Because acquiring a large dataset for this problem is impractical, generating it from simulation is the obvious alternative. However, this requires the use of a frictional contact simulator whose results are not only visually plausible, but physically-correct enough to match observations made at the macroscopic scale. In this paper, which is an extended version of our former work A. H. Rasheed, V. Romero, F. Bertails-Descoubes, S. Wuhrer, J.-S. Franco, and A Lazarus, "Learning to measure the static friction coefficient in cloth contact," in Proc. IEEE/CVF Conf. Comput. Vis. Pattern Recognit., 2020, pp. 9909-9918, we propose to our knowledge the first non-invasive measurement network and adjoining synthetic training dataset for estimating cloth friction at contact, for both cloth-hard body and cloth-cloth contacts. To this end we build a protocol for validating and calibrating a state-of-the-art frictional contact simulator, in order to produce a reliable dataset. We furthermore show that without our careful calibration procedure, the training fails to provide accurate estimation results on real data. We present extensive results on a large acquired test set of several hundred real video sequences of cloth in friction, which validates the proposed protocol and its accuracy.

Leadless intracardiac transcatheter pacing system: 20 months follow up in adult Duchenne muscular dystrophy.

Duchenne muscular dystrophy (DMD) is an X-linked muscular dystrophy in relation with dystrophin deficient. Heart and respiratory function are classically involved and affect long-term prognosis. Significant atrio-ventricular block may occur in some patients. Implantation of traditional pacemaker may be challenging in patients with tracheotomy and on permanent home mechanical ventilation. We report the first case of a successful leadless intra-cardiac trans-catheter pacing system implantation in an adult DMD on wheelchair and on permanent home mechanical ventilation.

Use of a radiofrequency guidewire to simplify workflow for left atrium access: a case series.

PURPOSE: Transseptal puncture (TSP) is widely used in catheter-based cardiac procedures to gain left atrial access, but its workflow has remained largely unchanged in the last 50 years. This study evaluated the safety and efficacy of a novel, simplified technique for TSP with a radiofrequency (RF)-powered guidewire that eliminates multiple exchanges required with standard needles. METHODS: TSP was performed in 84 patients undergoing left-sided procedures (72 atrial fibrillation ablations [32 RF, 40 cryoballoon], 4 atrial tachycardia ablations, 2 ventricular arrhythmia ablations, 6 left atrial appendage closure) utilizing a stiff, exchange length RF guidewire. Under fluoroscopic and echocardiographic guidance, the RF guidewire was used to facilitate septal puncture with RF energy and provide a rail for advancing catheters to the left atrium without exchange. All procedures were performed under general anesthesia or sedation. RESULTS: TSP was achieved in all patients with no complications. The RF guidewire allowed catheters to be tracked back up to the superior vena cava without exchange in cases where another dropdown was desired to locate a preferred puncture site. The stiffness of the wire provided adequate support to advance all sheaths to the left side regardless of outer diameter. CONCLUSION: TSP was performed safely and successfully for various left heart procedures with a RF guidewire that served as an RF transseptal device and a stiff guidewire. This allowed for a more efficient and potentially safer technique without the need for re-wiring or an over the wire sheath exchange. This provides substantial savings in both time and materials.

Role of medical reaction in management of inappropriate ventricular arrhythmia diagnosis: the inappropriate Therapy and HOme monitoRiNg (THORN) registry.

AIMS: Implantable cardioverter-defibrillators (ICDs) reduce sudden cardiac death in selected patients but inappropriate ICD shocks have been associated with increased mortality. The THORN registry aims to describe the rate of inappropriate ventricular arrhythmia diagnoses and therapies in patients followed by remote monitoring, as well as the following delay to next patient contact (DNPC). METHODS AND RESULTS: One thousand eight hundred and eighty-two patients issued from a large remote monitoring database first implanted with an ICD for primary or secondary prevention in 110 French hospitals from 2007 to 2014 constitute the THORN population. Among them, 504 patients were additionally followed prospectively for evaluation of the DNPC. Eight hundred and ninety-five out of 1551 (58%) patients had ischaemic heart disease and 358/771 (46%) were implanted for secondary prevention. During 13.7 ± 3.4 months of follow-up, the prevalence of first inappropriate diagnosis in a ventricular arrhythmia zone with enabled therapy was 162/1882 (9%). Among those patients, 122/162 (75%) suffered at least one inappropriate therapy and 58/162 (36%) at least one inappropriate shock. Eighty-three out of 162 (51%) of first inappropriate diagnosis occurred during the first 4 months following implantation. The median DNPC was 8 days (interquartile range 1-26). At least one other day with recording of an inappropriate diagnosis of the same cause occurred in 13/43 (30%) of available DNPC periods, with an inappropriate therapy in 7/13 (54%). CONCLUSION: Inappropriate diagnoses occurred in 9% of patients implanted with an ICD during the first 14 months. The DNPC after inadequate ventricular arrhythmia diagnoses remains long in daily practice and should be optimized. CLINICALTRIALS.GOV IDENTIFIER: NCT01594112.

Active periodic electrograms in remote monitoring of pacemaker recipients: the PREMS study.

AIMS: Remote monitoring (RM) is considered as a standard of care for pacemaker recipients. Remote monitoring systems provide calendar-based intracardiac electrogram recordings (IEGM) only with the current pacemaker settings (passive IEGM). PREMS (Pacemaker Remote Electrogram Monitoring Study), an observational, multicentre trial, prospectively evaluated the clinical value of an active IEGM (aIEGM), including three 10-s sections (passive IEGM, encouraged sensing, and encouraged pacing), compared to other RM data and to its passive IEGM section. Secondary objectives included the added value of the aIEGM to fully assess the sensing and pacing functions of each lead. METHODS AND RESULTS: Patients were enrolled within 3 months after pacemaker implantation and followed until the first transmitted aIEGM, which was analysed together with all other RM data. In total, 567 patients were enrolled (79 ± 9 years, 62% men, 19% single-chamber, and 81% dual-chamber pacemakers). Of 547 aIEGMs transmitted in 547 patients, 161 [29.4%; 95% confidence interval (95% CI) 25.6-33.3%] indicated at least one anomaly non-detectable with certainty-or at all-on other RM data, including atrial arrhythmia, extrasystoles, undersensing, oversensing, and loss of capture. In 21.7% of cases the detected events deserved a corrective action. The sensing and pacing function of each lead could be fully assessed in 77.3% of aIEGM (95% CI 72.6-82.0%) vs. 15.5% (95% CI 11.4-19.6%) when considering only the passive IEGM section (P < 0.001). CONCLUSION: An active IEGM improves the clinical value of remote pacemaker follow-up. Furthermore, compared to a passive IEGM, the aIEGM increases the capability to fully assess remotely the sensing and pacing functions.

Inverse design of an isotropic suspended Kirchhoff rod: theoretical and numerical results on the uniqueness of the natural shape.

Solving the equations for Kirchhoff elastic rods has been widely explored for decades in mathematics, physics and computer science, with significant applications in the modelling of thin flexible structures such as DNA, hair or climbing plants. As demonstrated in previous experimental and theoretical studies, the natural curvature plays an important role in the equilibrium shape of a Kirchhoff rod, even in the simple case where the rod is isotropic and suspended under gravity. In this paper, we investigate the reverse problem: can we characterize the natural curvature of a suspended isotropic rod, given an equilibrium curve? We prove that although there exists an infinite number of natural curvatures that are compatible with the prescribed equilibrium, they are all equivalent in the sense that they correspond to a unique natural shape for the rod. This natural shape can be computed efficiently by solving in sequence three linear initial value problems, starting from any framing of the input curve. We provide several numerical experiments to illustrate this uniqueness result, and finally discuss its potential impact on non-invasive parameter estimation and inverse design of thin elastic rods.

Bending transition in the penetration of a flexible intruder in a two-dimensional dense granular medium.

We study the quasistatic penetration of a flexible beam into a two-dimensional dense granular medium lying on a horizontal plate. Rather than a buckling-like behavior we observe a transition between a regime of crack-like penetration in which the fiber only shows small fluctuations around a stable straight geometry and a bending regime in which the fiber fully bends and advances through series of loading and unloading steps. We show that the shape reconfiguration of the fiber is controlled by a single nondimensional parameter L/L_{c}, which is the ratio of the length of the flexible beam L to L_{c}, a bending elastogranular length scale that depends on the rigidity of the fiber and on the departure from the jamming packing fraction of the granular medium. We show, moreover, that the dynamics of the bending transition in the course of the penetration experiment is gradual and is accompanied by a symmetry breaking of the granular packing fraction in the vicinity of the fiber. Together with the progressive bending of the fiber, a cavity grows downstream of the fiber and the accumulation of grains upstream of the fiber leads to the development of a jammed cluster of grains. We discuss our experimental results in the framework of a simple model of bending-induced compaction and we show that the rate of the bending transition only depends on the control parameter L/L_{c}.

Development and Validation of a New Scoring System to Predict Survival in Patients With Myotonic Dystrophy Type 1.

Importance: Life expectancy is greatly shortened in patients presenting with myotonic dystrophy type 1 (DM1), the most common neuromuscular disease. A reliable prediction of survival in patients with DM1 is critically important to plan personalized health supervision. Objective: To develop and validate a prognostic score to predict 10-year survival in patients with DM1. Design, Setting, and Participants: In this longitudinal cohort study, between January 2000 and November 2014, we enrolled 1296 adults referred to 4 tertiary neuromuscular centers in France for management of genetically proven DM1, including 1066 patients in the derivation cohort and 230 in the validation cohort. Data were analyzed from December 2016 to March 2017. Main Outcomes and Measures: Factors associated with survival by multiple variable Cox modeling, including 95% confidence intervals, and development of a predictive score validated internally and externally. Mean values are reported with their standard deviations. Results: Of the 1296 included patients, 670 (51.7%) were women, and the mean (SD) age was 39.8 (13.7) years. Among the 1066 patients (82.3%) in the derivation cohort, 241 (22.6%) died over a median (interquartile range) follow-up of 11.7 (7.7-14.3) years. Age, diabetes, need for support when walking, heart rate, systolic blood pressure, first-degree atrioventricular block, bundle-branch block, and lung vital capacity were associated with death. Simplified score points were attributed to each predictor, and adding these points yielded scores between 0 and 20, with 0 indicating the lowest and 20 the highest risk of death. The 10-year survival rate was 96.6% (95% CI, 94.4-98.9) in the group with 0 to 4 points, 92.2% (95% CI, 88.8-95.6) in the group with 5 to 7 points, 80.7% (95% CI, 75.4-86.1) in the group with 8 to 10 points, 57.9% (95% CI, 49.2-66.6) in the group with 11 to 13 points, and 19.4% (95% CI, 8.6-30.1) in the group with 14 points or more. In 230 patients (17.7%) included in the validation cohort, the 10-year survival rates for the groups with 0 to 4, 5 to 7, 8 to 10, 11 to 13, and 14 points or more were 99.3% (95% CI, 95.0-100), 80.6% (95% CI, 67.1-96.7), 79.3% (95% CI, 66.2-95.1), 43.2% (95% CI, 28.2-66.1), and 21.6% (95% CI, 10.0-46.8), respectively. The calibration curves did not deviate from the reference line. The C index was 0.753 (95% CI, 0.722-0.785) in the derivation cohort and 0.806 (95% CI, 0.758-0.855) in the validation cohort. Conclusions and Relevance: The DM1 prognostic score is associated with long-term survival.

Risk for Complications after Pacemaker or Cardioverter Defibrillator Implantations in Patients with Myotonic Dystrophy Type 1.

BACKGROUND: Pacemakers (PM) and implantable cardioverter defibrillators (ICD) may be indicated for sudden death prevention in myotonic dystrophy type 1 (DM1), however the risk of complications after the placement of these devices is unknown. OBJECTIVE: To compare the rate of device-related complications between PM and ICD implantations in patients with DM1. METHODS: Among 914 patients with DM1 included in the DM1 Heart Registry between January 2000 and January 2010, we retrospectively selected 23 patients who were implanted with an ICD and matched them to 46 controls with a PM on age, gender, and year of device placement. RESULTS: Over a 6 years follow-up period, we observed device-related complications in 9 ICD recipients (inappropriate shocks in 5, lead dysfunction in 5, infection in 2) and in 3 PM recipients (lead dysfunction in 3). Patients with an ICD had, compared to those with a PM, higher rates of complications (39.1% vs. 6.5%, p = 0.0006) and more frequent complications requiring hospitalisation and/or re-intervention (respectively 30.4% and 21.7% vs. 0%). CONCLUSION: Our study shows a higher risk of device-related complications after the implantation of an ICD than for a PM in patients presenting with DM1.

Association Between Mutation Size and Cardiac Involvement in Myotonic Dystrophy Type 1: An Analysis of the DM1-Heart Registry.

BACKGROUND: In myotonic dystrophy type 1, the association between mutation size (CTG expansion) and the severity of cardiac involvement is controversial. METHODS AND RESULTS: We selected 855 patients with myotonic dystrophy type 1 (women, 51%; median age, 37 years), with genetic testing performed at the moment of their initial cardiac evaluation, out of 1014 patients included in the Myotonic Dystrophy Type 1-Heart Registry between January 2000 and December 2015. We studied the association between CTG expansion size and other baseline characteristics and (1) cardiac involvement at baseline and (2) the incidence of death, sudden death, and other cardiac adverse events. At initial presentation, the median CTG expansion size was 530 (interquartile range, 300-830). In multivariate analysis, larger expansions were associated with the presence at baseline of conduction defects on the ECG and left ventricular systolic dysfunction. In a median 11.5 years of follow-up period, 210 patients died (25%), including 32 suddenly (4%). Supraventricular arrhythmias developed over lifetime in 166 patients (19%), sustained ventricular tachyarrhythmias in 17 (2%), and permanent pacemakers were implanted in 181 (21%). In Cox regression analyses, larger CTG expansions were significantly associated with (1) total death, sudden death, and pacemaker implantation in a model, including CTG expansion size, age, sex, diabetes mellitus, and (2) all end points except sudden death in a model including all baseline characteristics. CONCLUSIONS: The size of the CTG expansion in the blood of myotonic dystrophy type 1 patients is associated with total and sudden deaths, conduction defects, left ventricular dysfunction, and supraventricular arrhythmias. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique Identifier: NCT01136330.

Early Detection and Treatment of Atrial Arrhythmias Alleviates the Arrhythmic Burden in Paced Patients: The SETAM Study.

BACKGROUND: Remote monitoring (RM) can remotely detect atrial tachyarrhythmias (ATAs). The benefit of RM compared to conventional follow-up in the detection and management of ATA was assessed in recipients of dual-chamber pacemakers. METHODS: The multicenter randomized SETAM study enrolled 595 patients in sinus rhythm with a CHA2 DS2 -VASc score ≥2, without ATA history and untreated with antiarrhythmics and antithrombotics, randomly assigned to RM (RM-ON; n = 291) versus ambulatory follow-up (RM-OFF; n = 304) during 12.8 ± 3.3 months. ATA occurrence, burden, and management were analyzed together with adverse clinical events. RESULTS: Patients were 79 ± 8 years old, 63% men, with a CHA2 DS2 -VASc score of 3.7± 1.2. ATA were detected in 83 patients (28%) in the RM-ON versus 66 (22%) in the RM-OFF group (P = 0.06). The median time between the pacemaker implantation and the first treated ATA was 114 days [44; 241] in the RM-ON versus 224 days [67; 366] in the RM-OFF group (hazard ratio [HR] = 0.56; 95% confidence interval [CI]: 0.37-0.86; P = 0.01). Therapies for ATA were initiated in 92 patients and the time to treatment of ATA was shortened by 44% in the RM-ON group (HR = 0.565; 95% CI: 0.37-0.86; P = 0.01). Over the last 4 months of follow-up, the mean ATA burden was alleviated by 4 hours/day (18%) in the RM-ON group. The rate of adverse clinical events was similar in both groups. CONCLUSION: Remotely monitored patients were diagnosed and treated earlier for ATA, and subsequently had a lower ATA burden.

Optimizing Implantable Cardioverter-Defibrillator Remote Monitoring: A Practical Guide.

Remote monitoring (RM) receives a Class I: Level of Evidence: A recommendation for the follow-up of patients with implantable cardioverter-defibrillators, positioning the technology as standard of care. RM is often seen and sold as a plug-and-play technology, whereas fundamental differences exist in the philosophy and conception of the 5 main RM systems. The capabilities and limitations of the different RM systems need to be understood and taken into account when the decision is made to remotely manage an individual patient. The purpose of this review is to provide to the cardiologist practical information about RM systems' specificities with respect to the different technical and clinical alerts. Clinically based indications and programming suggestions are provided.

Incidence and predictors of sudden death, major conduction defects and sustained ventricular tachyarrhythmias in 1388 patients with myotonic dystrophy type 1.

AIMS: To describe the incidence and identify predictors of sudden death (SD), major conduction defects and sustained ventricular tachyarrhythmias (VTA) in myotonic dystrophy type 1 (DM1). METHODS AND RESULTS: We retrospectively enrolled 1388 adults with DM1 referred to six French medical centres between January 2000 and October 2013. We confirmed their vital status, classified all deaths, and determined the incidence of major conduction defects requiring permanent pacing and sustained VTA. We searched for predictors of overall survival, SD, major conduction defects, and sustained VTA by Cox regression analysis. Over a median 10-year follow-up, 253 (18.2%) patients died, 39 (3.6%) suddenly. Analysis of the cardiac rhythm at the time of the 39 SD revealed sustained VTA in 9, asystole in 5, complete atrioventricular block in 1 and electromechanical dissociation in two patients. Non-cardiac causes were identified in the five patients with SD who underwent autopsies. Major conduction defects developed in 143 (19.3%) and sustained VTA in 26 (2.3%) patients. By Cox regression analysis, age, family history of SD and left bundle branch block were independent predictors of SD, while age, male sex, electrocardiographic conduction abnormalities, syncope, and atrial fibrillation were independent predictors of major conduction defects; non-sustained VTA was the only predictor of sustained VTA. CONCLUSIONS: SD was a frequent mode of death in DM1, with multiple mechanisms involved. Major conduction defects were by far more frequent than sustained VTA, whose only independent predictor was a personal history of non-sustained VTA. ClinicalTrials.gov no: NCT01136330.

Cardiac implantable electronic devices in tracheotomized muscular dystrophy patients: Safety and risks.

BACKGROUND/OBJECTIVES: Muscular dystrophies are genetic muscle disorders, in which heart involvement and chronic respiratory impairment affect survival. Cardiac conduction disturbances require implantable cardiac pacemaker. Implantable defibrillators may also be necessary to prevent cardiac sudden death. The safety and risk of cardiac electronic devices' implantation are not known in patients with muscular dystrophy. We aimed to assess the risks related to cardiac implantable electronic devices (CIED) in muscular dystrophy patients ventilated by tracheostomy. METHODS: We reviewed all medical charts of neuromuscular patients and identified all CIED implantations of pacemakers (PM) or defibrillators (ICD) in patients ventilated using tracheostomy. RESULTS: Twelve device implantations were included, performed in 9 patients (5 DMD, 1 Becker muscular dystrophy and 3 DM1). Mean age was 39.9years±13.0. All patients were wheel-chair bound and tracheotomized. Six pacemakers (PM) and 6 cardiac resynchronization (CRT) devices, including 2 defibrillators (CRT-D) were implanted. Following device implantation, two patients had a pneumothorax and one died from severe heart failure after an unsuccessful CRT implant attempt. Follow-up lasted up to 8years (mean 2.6±2.9years), during which one patient presented a PM pocket infection, requiring PM explantation and epicardial reimplantation. CONCLUSION: We found a high prevalence of early complications (16.6% pneumothorax) after CIED implantation and an acceptable long-term infectious risk (8.3%). These results highlight the feasibility of CIED implantation in tracheotomized patients with muscular dystrophies and the need for a particular caution in the management of these patients during invasive procedures. ClinicalTrials.gov (identifier: NCT02501083).

Atrial flutter in myotonic dystrophy type 1: Patient characteristics and clinical outcome.

The prevalence and the incidence of atrial flutter in patients with myotonic dystrophy type 1 (DM1) and the most appropriate strategies for its management are unknown. We retrospectively included in the DM1 Heart Registry 929 adult patients with DM1 admitted to our Institutions between January 2000 and September 2013. We selected patients presenting with atrial flutter and analysed data relative to the occurrence of arterial thromboembolism, severe bradyarrhythmias and atrial flutter recurrences. Atrial flutter was present in 79 of the 929 patients included in our Registry, representing a 8.5% prevalence. Patients with atrial flutter were older, had a higher muscular disability rating scale score and had higher prevalence of other cardiac manifestations of DM1. Sixty patients presented with a first episode of atrial flutter, representing a 4.6% incidence. Severe bradyarrhythmias requiring permanent pacing were present in 4 patients (6.7%). Over a 53 ± 28 months mean follow-up duration, 2 patients (3.3%) had ischaemic stroke and 12 (20%) had atrial flutter recurrences. Patients who underwent radiofrequency ablation were more frequently free of atrial flutter recurrence than other patients (95 vs. 61%; HR = 0.17; P = 0.04). Atrial flutter is a common manifestation of DM1, potentially complicated by arterial thromboembolism or severe bradyarrhythmias. Radiofrequency catheter ablation is associated with a lower risk for recurrences.