Conduction System Pacing versus Conventional Biventricular Pacing for Cardiac Resynchronization Therapy: Where Are We Heading?

Over the last few years, pacing of the conduction system (CSP) has emerged as the new standard pacing modality for bradycardia indications, allowing a more physiological ventricular activation compared to conventional right ventricular pacing. CSP has also emerged as an alternative modality to conventional biventricular pacing for the delivery of cardiac resynchronization therapy (CRT) in heart failure patients. However, if the initial clinical data seem to support this new physiological-based approach to CRT, the lack of large randomized studies confirming these preliminary results prevents CSP from being used routinely in clinical practice. Furthermore, concerns are still present regarding the long-term performance of pacing leads when employed for CSP, as well as their extractability. In this review article, we provide the state-of-the-art of CSP as an alternative to biventricular pacing for CRT delivery in heart failure patients. In particular, we describe the physiological concepts supporting this approach and we discuss the future perspectives of CSP in this context according to the implant techniques (His bundle pacing and left bundle branch area pacing) and the clinical data published so far.

A multicomponent complex intervention for supportive follow-up of persons with chronic heart failure: a randomized controlled pilot study (the UTILE project).

BACKGROUND: Heart failure (HF) is a progressive disease associated with a high burden of symptoms, high morbidity and mortality, and low quality of life (QoL). This study aimed to evaluate the feasibility and potential outcomes of a novel multicomponent complex intervention, to inform a future full-scale randomized controlled trial (RCT) in Switzerland. METHODS: We conducted a pilot RCT at a secondary care hospital for people with HF hospitalized due to decompensated HF or with a history of HF decompensation over the past 6 months. We randomized 1:1; usual care for the control (CG) and intervention group (IG) who received the intervention as well as usual care. Feasibility measures included patient recruitment rate, study nurse time, study attrition, the number and duration of consultations, intervention acceptability and intervention fidelity. Patient-reported outcomes included HF-specific self-care and HF-related health status (KCCQ-12) at 3 months follow-up. Clinical outcomes were all-cause mortality, hospitalization and days spent in hospital. RESULTS: We recruited 60 persons with HF (age mean = 75.7 years, ± 8.9) over a 62-week period, requiring 1011 h of study nurse time. Recruitment rate was 46.15%; study attrition rate was 31.7%. Follow-up included 2.14 (mean, ± 0.97) visits per patient lasting a total of 166.96 min (mean, ± 72.55), and 3.1 (mean, ± 1.7) additional telephone contacts. Intervention acceptability was high. Mean intervention fidelity was 0.71. We found a 20-point difference in mean self-care management change from baseline to 3 months in favour of the IG (Cohens' d = 0.59). Small effect sizes for KCCQ-12 variables; less IG participants worsened in health status compared to CG participants. Five deaths occurred (IG = 3, CG = 2). There were 13 (IG) and 18 (CG) all-cause hospital admissions; participants spent 8.90 (median, IQR = 9.70, IG) and 15.38 (median, IQR = 18.41, CG) days in hospital. A subsequent full-scale effectiveness trial would require 304 (for a mono-centric trial) and 751 participants (for a ten-centre trial) for HF-related QoL (effect size = 0.3; power = 0.80, alpha = 0.05). CONCLUSION: We found the intervention, research methods and outcomes were feasible and acceptable. We propose increasing intervention fidelity strategies for a full-scale trial. TRIAL REGISTRATION: ISRCTN10151805 , retrospectively registered 04/10/2019.

[Epicardial adipose tissue and atrial fibrillation]. / Tissu adipeux épicardique et fibrillation auriculaire.

Atrial fibrillation (AF) is the most common arrhythmia encountered in adults; it is associated with a significant morbidity and mortality. Obesity is a risk factor contributing to AF occurrence. Recently, interest has focused on epicardial adipose tissue (EAT), defined as a fatty deposit located between the epicardium and the visceral pericardium. Its characteristics are distinct from classic adipose deposits: it infiltrates the epicardial myocardium and secretes cytokines, which modulate cardiomyocyte electrophysiology and cardiac remodeling. Different studies show that EAT can be an independent risk factor for AF and that EAT thickness, as measured by CT or MRI, could predict the presence, severity and recurrence of AF.

La fibrillation auriculaire (FA) est l'arythmie la plus fréquemment rencontrée chez l'adulte ; elle est associée à une morbi-mortalité importante. L'obésité est un facteur de risque contribuant à sa survenue. Récemment, l'intérêt s'est porté sur le tissu adipeux épicardique (TAE), défini comme un dépôt adipeux situé entre l'épicarde et le péricarde viscéral. Ses caractéristiques sont distinctes des dépôts adipeux classiques : il infiltre le myocarde épicardique et sécrète des cytokines modulant l'électrophysiologie des cardiomyocytes et provoquant un remodelage fibro-adipeux cardiaque. Différentes études montrent que le TAE peut être un facteur de risque indépendant de survenue de FA. L'épaisseur du TAE mesurée par CT-scan ou par IRM pourrait être utilisée comme facteur prédictif de la présence, de la gravité et de la récidive de FA.

New Insights in Central Venous Disorders. The Role of Transvenous Lead Extractions.

Over the last decades, the implementation of new technology in cardiac pacemakers and defibrillators as well as the increasing life expectancy have been associated with a higher incidence of transvenous lead complications over time. Variable degrees of venous stenosis at the level of the subclavian vein, the innominate trunk and the superior vena cava are reported in up to 50% of implanted patients. Importantly, the number of implanted leads seems to be the main risk factor for such complications. Extraction of abandoned or dysfunctional leads is a potential solution to overcome venous stenosis in case of device upgrades requiring additional leads, but also, in addition to venous angioplasty and stenting, to reduce symptoms related to the venous stenosis itself, i.e., the superior vena cava syndrome. This review explores the role of transvenous lead extraction procedures as therapeutical option in case of central venous disorders related to transvenous cardiac leads. We also describe the different extraction techniques available and other clinical indications for lead extractions such as lead infections. Finally, we discuss the alternative therapeutic options for cardiac stimulation or defibrillation in case of chronic venous occlusions that preclude the implant of conventional transvenous cardiac devices.

Rapidly progressive heart failure after dual-chamber pacemaker implantation.

Pacing-induced cardiomyopathy (PICM) consists of heart failure (HF) associated with a drop in the left ventricular ejection fraction (LVEF) in the setting of high-burden right ventricular pacing, with presentation that may range from subclinical to severe. Time to manifestation can go from weeks to years after device implantation. Treatment typically consists in an upgrade to a cardiac resynchronisation therapy (CRT) or His bundle pacing (HisP). Several risk factors for PICM have been described and should be considered before pacemaker (PM) implantation, as thorough patient selection for de novo CRT or HisP, may preclude its manifestation. We present the case of an 82-year-old patient presenting with acute congestive HF and new severely reduced LVEF, 30 days following dual chamber PM implantation for high-grade atrioventricular block. Treatment with HF medication and upgrade to a CRT permitted rapid resolution of the symptoms and normalisation of the LVEF at 1-month follow-up.

Temporary atrial overdrive pacing during a drug-refractory electrical storm in acute myocardial infarction.

A 64-year-old man with diabetes mellitus was diagnosed with a non-ST-segment elevation myocardial infarction and was treated with stent implantation. Four days later, he developed an electrical storm (ES) that persisted despite antiarrhythmic drugs and sedation. External defibrillation was performed more than 100 times over 2 hours. After ruling out the common causes of polymorphic ventricular tachycardia, an ES was considered because of brady-dependent R-on-T phenomenon, presumably precipitated by antiarrhythmic drugs. Temporary transvenous atrial overdrive pacing allowed complete suppression of premature ventricular complexes and ventricular fibrillation.

Self-care, symptom experience, needs, and past health-care utilization in individuals with heart failure: results of a cross-sectional study.

AIMS: Self-care in heart failure (HF) is generally sub-optimal and impacts morbidity and mortality. To describe self-care prevalence and explore its relationships with symptom experience, patient needs, and health-care utilization in a Swiss hospital providing regional secondary care. METHODS AND RESULTS: Cross-sectional study, convenience sample of individuals with HF from four campuses of one regional Swiss hospital. Self-care was assessed via the Self-Care of Heart Failure Index (SCHFI) and the European Heart Failure Self-care Behaviour Scale (EHFScBS), symptom experience via the M.D. Anderson Symptom Inventory-HF (MDASI-HF) and needs via the Heart Failure Needs Assessment Questionnaire (HFNAQ). Healthcare utilization reflected the preceding year's hospitalization incidence. A cut-off level of ≥70% indicated adequate self-care. We analysed SCHFI, EHFScBS, MDASI-HF and HFNAQ scores' relationships with hospitalizations using Spearman's rho correlation; no prior hypotheses were stated. Sample of 310 individuals with HF (37.4% female; mean age 76.8; 55% NYHA III). Adequate self-care maintenance, management, and confidence were reported by 24%, 10%, and 61%. respectively. The sample's mean number of experienced symptoms was 12.8 (SD 4.0) and 14.0 (SD 5.8) for needs. Over the previous year, 269 hospitalizations had occurred (median: 0, IQR 1). Hospitalizations positively correlated with self-care; symptom experience with needs. Neither symptom experience nor needs correlated with hospitalizations. CONCLUSION: The findings indicated low self-care levels and suggest a need for increased support to maintain physiological stability, manage symptoms and prevent hospitalizations. This study is the first of its kind in Switzerland and among few studies worldwide to report on self-care, symptom experience, needs, and health-care utilization. Interventional studies are warranted considering baseline self-care capabilities, symptoms, and needs of individuals with HF.

[Pacemakers and defibrillators: what the non-specialist needs to know]. / Pacemakers et défibrillateurs: ce que le non-spécialiste doit savoir.

Cardiologists are in charge of the follow-up of patients equipped with pacemakers and defibrillators. In many situations, however, the non-specialist will have to take care of these patients. It is therefore essential that the practitioner understands the basics of how these devices work, the potential complications and the situations in which the cardiologist's intervention is necessary. This article summarizes implantation techniques, post-operative follow-up and potential complications of implantable devices. It recapitulates the differences between pacemaker, defibrillator and resynchronization therapy. It explains the stimulation modes and reminds the reader how the magnet works and the precautions to be taken in the operating theatre, during magnetic resonance imaging or in situations of emergency.

Le suivi des patients porteurs de pacemakers et de défibrillateurs incombe au cardiologue. Dans de nombreuses situations néanmoins, le non-spécialiste devra prendre en charge ces patients. Il demeure donc essentiel que le praticien soit familier avec les bases du fonctionnement de ces dispositifs, les potentielles complications et les situations pour lesquelles l'intervention du cardiologue s'avère nécessaire. Cet article résume les techniques d'implantation, le suivi postopératoire et les complications potentielles de ces dispositifs médicaux; il rappelle également les différences entre pacemaker, défibrillateur et thérapie de resynchronisation. Il revient finalement sur les modes de stimulation, le fonctionnement de l'aimant ainsi que sur les précautions à prendre au bloc opératoire, lors d'examens par résonance magnétique ou en situation d'urgence.

Efficiency of the RADPAD Surgical Cap in Reducing Brain Exposure During Pacemaker and Defibrillator Implantation.

OBJECTIVES: This study sought to investigate the RADPAD No Brainer (Worldwide Innovation and Technologies, Overland Park, Kansas) efficiency in reducing brain exposure to scattered radiation. BACKGROUND: Cranial radioprotective caps such as the RADPAD No Brainer are being marketed as devices that significantly reduce operator's brain exposure to scattered radiation. However, the efficiency of the RADPAD No Brainer in reducing brain exposure in clinical practice remains unknown to date. METHODS: Five electrophysiologists performing device implantations over a 2-month period wore the RADPAD cap with 2 strips of 11 thermoluminescent dosimeter pellets covering the front head above and under the shielded cap. Phantom measurements and Monte Carlo simulations were performed to further investigate brain dose distribution. RESULTS: Our study showed that the right half of the operators' front head was the most exposed region during left subpectoral device implantation; the RADPAD cap attenuated the skin front-head exposure but provided no protection to the brain. The exposure of the anterior part of the brain was decreased by a factor of 4.5 compared with the front-head skin value thanks to the skull. The RADPAD cap worn as a protruding horizontal plane, however, reduced brain exposure by a factor of 1.7 (interquartile range: 1.3 to 1.9). CONCLUSIONS: During device implantation, the RADPAD No Brainer decreased the skin front head exposure but had no impact on brain dose distribution. The RADPAD No Brainer worn as a horizontal plane worn around the neck reduces brain exposure and confirms that the exposure comes from upward scattered radiation.

[Cardiology]. / Cardiologie.

In 2019, the guidelines on the new entity « chronic coronary syndrome ¼ have been published. They influence importantly the work-up and treatment of patients with stable coronary artery disease. We will also report on publications showing the benefit of percutaneous aortic valve implantation (TAVI) in patients with aortic stenosis and low risk surgical risk. With regard to infectious endocarditis, we elucidate the importance of the vegetation's size for predicting mortality and the prognostic value of the positron emission tomography in predicting septic embolism. We highlight the spectacular results of the DAPA-HF study in patients with heart failure and review publications showing the important role of the detection of myocardial fibrosis and scar by cardiac MRI for risk stratification of sudden cardiac death.

L'année 2019 a été marquée par la publication de recommandations sur une nouvelle entité, appelée « syndrome coronarien chronique ¼, qui modifient de manière importante la prise en charge et le traitement des patients avec une maladie coronarienne stable. On relève plusieurs publications démontrant, chez les patients ayant une sténose aortique, et étant à bas risque chirurgical, le bénéfice d'un traitement percutané par rapport à un traitement chirurgical. La prise en charge de l'endocardite a été challengée par deux publications montrant que la taille de la végétation est un facteur de risque de mortalité et la valeur pronostique de la tomographie par émission de positons dans la survenue d'emboles septiques. Nous discutons les résultats spectaculaires de l'étude DAPA-HF dans le domaine d'insuffisance cardiaque et plusieurs études montrant l'intérêt de la recherche de cicatrice myocardique à l'IRM cardiaque dans la stratification du risque de mort subite.

Arrhythmic episodes in patients implanted with a cardioverter-defibrillator - results from the Prospective Study on Predictive Quality with Preferencing PainFree ATP therapies (4P).

BACKGROUND: Little is known about the ICD performance using enhanced detection algorithms in unselected, non-trial patients. Performance of recent generation ICD equipped with SmartShock™ technology (SST) for detection and conversion of ventricular tachyarrhythmias (VTA) was investigated. METHODS: 4P was a prospective, multicenter, observational study conducted in 10 Swiss implanting centers. Patients with a Class I indication according to international guidelines were included and received an ICD with SST. ICD discrimination capability was assessed by evaluating SST performance; therapy efficacy was assessed by rate of VTA conversions by ATP and by rescue shocks. RESULTS: Overall, 196 patients were included in the analysis with a mean duration of follow-up of 27.7 months (452 patient-years of observation). Patient-specific rather than recommended programming was preferred. Device-detected episodes were frequent (5147 episodes in 146 patients, 74.5%). In 44 patients (22.4%), 1274 episodes were categorized as VTA; only 215 episodes were symptomatic. ATP was the first-line therapy and highly effective (99.9% success rate at the episode level, 100.0% at the patient level). Rescue shocks were rare (66 episodes in 28 patients); 7 shocks in 5 patients (2.6%) were inappropriate. Death and hospitalization rates were low. CONCLUSIONS: In a cohort of non-trial, unselected ICD patients, VTA episodes were frequent. The 4P results confirm the robustness of VTA detection by SST and the effectiveness of ATP treatment, hence limiting overall ICD shock burden.

Leadless pacing using the transcatheter pacing system (Micra TPS) in the real world: initial Swiss experience from the Romandie region.

AIMS: Leadless pacemakers are implanted in Switzerland since June 2015. Large worldwide registries have shown high implant success, low complication rates, and good electrical parameters up to 12 months' follow-up. However, data are scarce outside the investigational setting. The purpose of this study is to assess the real-world experience regarding clinical safety and efficacy of Micra TPS (transcatheter pacing system) leadless pacemakers. METHODS AND RESULTS: Retrospective observational, multi-centre study designed to assess initial safety and efficacy of the Micra TPS in the Swiss Romande region. A total of 92 patients were included from four different centres with an implantation success rate of 97.8% (90 of 92). Thresholds were overall low at implantation (median 0.38 V/0.24 ms, ranging from 0.13 to 2.88 V/0.24 ms) and remained stable over 1-year follow-up. The perioperative serious adverse event rate was 6.5% in six patients which lead to prolonged hospitalization in five patients and death in one patient. In addition, three further major events (3.3%) occurred during an average follow-up of 1 year, requiring implantation of a standard transvenous pacemaker in two patients, and surgical explantation of the Micra TPS in one patient due to intractable ventricular tachycardia. CONCLUSION: Leadless pacemakers are a valuable adjunct for treating selected patients requiring single-chamber pacing. However, in this initial experience, major complication rates were high (9.8%). The implant procedure requires proper training and should be performed in an adequate setting.

Heart rate never lies: interventional cardiologist and Braude's quote revised.

BACKGROUND: Interventional cardiologists may be immune to stress, allowing them to perform complex percutaneous interventions under pressure. OBJECTIVES: To assess heart rate (HR) variations as a surrogate marker of stress of interventional cardiologists during percutaneous cardiac procedures and in every-day life. DESIGN: This is a single-centre observational study including a total of six male interventional cardiologists performing coronary interventions and pacemaker implantations. Participants were asked to record their HR with the Apple Watch Device during procedures, every-day life and control activities such as outpatient consultations, sport, marital conflicts and sexual intercourse. RESULTS: Average daily HR was 88±17 bpm. During work days, HR increased significantly during procedures (90±17 bpm) compared with days outside the cathlab (87±17 bpm, p=0.02). The average HR was higher during a regular week working (88±16 bpm) compared with weekends off (84±18 bpm, p=0.002). Complex cardiac procedures were associated with higher HR up to 122 bpm. Peak HR were higher during physical exertion. Of note, participants complained of hypersexuality and mania after night shifts. CONCLUSIONS: Work and especially percutaneous cardiac procedures increase HR independently of physical exertion suggesting that interventional cardiologists experience mental stress and emotions.

New electrocardiographic criteria for discriminating between Brugada types 2 and 3 patterns and incomplete right bundle branch block.

OBJECTIVES: The aim of this study was to evaluate new electrocardiographic (ECG) criteria for discriminating between incomplete right bundle branch block (RBBB) and the Brugada types 2 and 3 ECG patterns. BACKGROUND: Brugada syndrome can manifest as either type 2 or type 3 pattern. The latter should be distinguished from incomplete RBBB, present in 3% of the population. METHODS: Thirty-eight patients with either type 2 or type 3 Brugada pattern that were referred for an antiarrhythmic drug challenge (AAD) were included. Before AAD, 2 angles were measured from ECG leads V(1) and/or V(2) showing incomplete RBBB: 1) α, the angle between a vertical line and the downslope of the r'-wave, and 2) ß, the angle between the upslope of the S-wave and the downslope of the r'-wave. Baseline angle values, alone or combined with QRS duration, were compared between patients with negative and positive results on AAD. Receiver-operating characteristic curves were constructed to identify optimal discriminative cutoff values. RESULTS: The mean ß angle was significantly smaller in the 14 patients with negative results on AAD compared to the 24 patients with positive results on AAD (36 ± 20° vs. 62 ± 20°, p < 0.01). Its optimal cutoff value was 58°, which yielded a positive predictive value of 73% and a negative predictive value of 87% for conversion to type 1 pattern on AAD; α was slightly less sensitive and specific compared with ß. When the angles were combined with QRS duration, it tended to improve discrimination. CONCLUSIONS: In patients with suspected Brugada syndrome, simple ECG criteria can enable discrimination between incomplete RBBB and types 2 and 3 Brugada patterns.

[Idiopathic premature ventricular complexes originating from the ventricular outflow tract: evaluation, prognosis and management]. / Extrasystoles ventriculaires idiopathiques de ta chambre de chasse: evaluation, pronostic et prise en charge.

Idiopathic premature ventricular complexes originating from the ventricular outflow tract: evaluation, prognosis and management The prognosis of ventricular premature complexes (VPC) in the absence of heart disease is considered benign. VPC usually originate from the right or, less commonly, left ventricular outflow tract. QRS complexes therefore usually assume a left bundle branch block and inferior axis morphology. These VPC, particularly if very frequent (> 20,000 per day), may adversely affect left ventricular function and their suppression can restore normal function. Moreover, there is a clinical overlap with arrhythmogenic right ventricular dysplasia and this diagnosis should be considered when facing a left bundle branch block shaped VPC. However, the prognosis of outflow tract VPC is good for appropriately selected patients with normal left ventricular function, absence of syncope or ventricular tachycardia, and no evidence of cardiac disease.

Stepwise evaluation of unexplained syncope in a large ambulatory population.

BACKGROUND: Up to 60% of syncopal episodes remain unexplained. We report the results of a standardized, stepwise evaluation of patients referred to an ambulatory clinic for unexplained syncope. METHODS AND RESULTS: We studied 939 consecutive patients referred for unexplained syncope, who underwent a standardized evaluation, including history, physical examination, electrocardiogram, head-up tilt testing (HUTT), carotid sinus massage (CSM) and hyperventilation testing (HYV). Echocardiogram and stress test were performed when underlying heart disease was initially suspected. Electrophysiological study (EPS) and implantable loop recorder (ILR) were used only in patients with underlying structural heart disease or major unexplained syncope. We identified a cause of syncope in 66% of patients, including 27% vasovagal, 14% psychogenic, 6% arrhythmias, and 6% hypotension. Noninvasive testing identified 92% and invasive testing an additional 8% of the causes. HUTT yielded 38%, CSM 28%, HYV 49%, EPS 22%, and ILR 56% of diagnoses. On average, patients with arrhythmic causes were older, had a lower functional capacity, longer P-wave duration, and presented with fewer prodromes than patients with vasovagal or psychogenic syncope. CONCLUSIONS: A standardized stepwise evaluation emphasizing noninvasive tests yielded 2/3 of causes in patients referred to an ambulatory clinic for unexplained syncope. Neurally mediated and psychogenic mechanisms were behind >50% of episodes, while cardiac arrhythmias were uncommon. Sudden syncope, particularly in older patients with functional limitations or a prolonged P-wave, suggests an arrhythmic cause.