View clinical trials related to Heart Block.
Filter by:The aim of this study is to compare the effectiveness of multiple modalities of cardiac resynchronisation therapy using high precision acute electrical and haemodynamic measurements.These modalities include biventricular pacing and conduction system pacing utilising His bundle and left bundle pacing. Conduction system pacing is a more physiological form of pacing. The study hypothesises that this will produce more effective cardiac resynchronisation.
Consecutive patients with high grade aortic stenosis undergoing transcatheter aortic valve replacement (TAVR) with a self-expanding valve (Medtronic CoreValve Evolut R® or Edwards Sapien S3®) without pre-existing pacemaker devices are eligible for inclusion. During the TAVR procedure, an electrophysiologic study including measurements of infranodal conduction times (HV-interval before and after valve implantation) will be performed. Electrocardiograms before TAVR, before discharge, after 30 days and after 12 months will be analyzed regarding new onset LBB and the occurrence of high-degree AV block (HAVB) .
The goal of this study is to assess the feasibility, accuracy and safety of performing fluoroless (or low fluoro) conduction system pacing utilizing electro-anatomic mapping (EAM) with the CARTO 3 mapping system (Biosense Webster Inc, Irvine, CA) in comparison to a group of patients undergoing conventional conduction system pacing (CSP) Implants.
This is a prospective, single-arm, non-randomized, non-blinded study designed to characterize the locations of His Bundle (HB) pacing that results in correction of electrical dyssynchrony and to characterize morphology and activation time of local intracardiac electrogram (IEGM) with an electro-anatomical mapping system during a device implant procedure and secondarily to assess the efficacy of HB pacing or HB plus LV pacing (when indicated) in correction of electrical dyssynchrony in heart failure patients with left bundle branch block.
The Physiologic Pacing Registry is a prospective, observational, multi-center registry performed to gain a broader understanding of 1) physiologic pacing implant and follow-up workflows, including pacing and sensing measurements and 2) the clinical utility in creating a 3-dimensional electro-anatomical map of cardiac structures prior to physiologic pacing device implants based on the clinical site's routine care.
RATIONALE: Cardiac resynchronization therapy (CRT) is known to improve cardiac performance and to reduce morbidity and mortality in reduced-ejection fraction heart failure (HFrEF) despite optimal medical therapy (OMT). Several studies have shown that patients with with left bundle branch block (LBBB) respond favourably to CRT, whereas there is less certainty about non-LBBB morphology. Specifically, whether patients with right bundle branch block (RBBB) and HFrEF benefit from CRT is unclear. Some studies suggest lack of favourable outcomes. It follows from this that VVI implantable defibrillator are implanted in most RBBB patients.On the other hand right ventricular bifocal stimulation could be useful as an alternative approach in patient with RBBB. It consists of two endocardial leads implanted in right ventricle. The first lead is implanted in His bundle area, and the second lead is in the right ventricle apex. In this way bifocal pacing could decrease the inter- and intraventricular delays, thus improving left ventricular hemodynamics. However no specifically randomized studies are designed to date. PURPOSE: To demonstrate the superiority of right ventricular bifocal stimulation over placebo (VVI implantable defibrillator) in RBBB and HFrEF despite OMT. DESIGN Multicenter prospective randomized, double blind cross-over study. MASKING Investigator responsible for device programming is masked from having knowledge about clinical, functional, and echocardiographic data. On the other hand echocardiographist is masked from having knowledge about stimulation mode. Patients are masked from having knowledge about their clinical, functional, and device data. POPULATION At least fifty patients would be enrolled. The enrollment period should be one year. Study overall duration should be two years. ELIGIBILITY CRITERIA RBBB and HFrEF (left ventricular ejection fraction ≤35%) in sinus rhythm, in NYHA class II-III or ambulatory IV despite OMT. EXCLUSION CRITERIA -Refusal or withdrawal of informed consent.Renal failure (glomerular filtration rate ≤ 60 ml/min).Life expectancy < 12 months.Active neoplasm.Permanent atrial fibrillation.40 days following acute coronary syndrome.Atrio-ventricular block (from second degree AV block).Valvular heart disease with surgery indications. PROTOCOL Each patient undergoes baseline assessment. Pharmacological therapy, hospitalization,NYHA functional class, QRS complex informations, type of heart disease and comorbidities are collected. Quality of life (QOL) is defined by Minnesota Living with Heart Failure questionnaire. Functional capacity is assessed by 6MWT (optionally by cardiopulmonary exercise test). Trans-thoracic echocardiogram is performed, analyzing: left-ventricle diameters and volumes, left-ventricle ejection fraction (LVEF), left atrial diameter and area, TAPSE,valvulopathy,systolic pulmonary artery pressure. All patients undergo bifocal right ventricular resynchronization therapy: right atrial lead is implanted, whereas the first ventricular lead is placed in His bundle area, and the second ventricular lead in the right ventricle apex. Then the leads are connected to the respective channels of a CRT-D generator.After the implant, all devices are programmed in VVI mode. After the first 40±10 days (first f-up) patients are 1:1 randomized to VVI mode 40 beats/minute (placebo arm) or bifocal DDD-mode 60 beats/minute (with VV delay 0 msec and optimal AV delay). After six months (second f-up) a clinical and instrumental assessment equal to baseline is performed, as well as devices electrical parameters control. Then arms cross-over is performed (from VVI-mode to bifocal DDD-mode and vice versa). At 12 months (end of follow-up) an evaluation equal to that performed at 6 months is assessed. Echocardiographic data are unravelled to the investigator responsible for device programming. In this way the stimulation mode able to determine the best clinical improved (VVI or bifocal DDD mode) is programmed and the study closes. PRIMARY ENDPOINT The main assumption is that bifocal stimulation can increase of at least 20% the distance walked during 6MWT in respect of baseline and VVI-mode.The primary endpoint is the distance walked (expressed by meters) during 6MWT, as assessed at baseline, 6-months follow-up and 12 months follow up. Specifically changes in 6MWT observed during bifocal DDD-mode compared to baseline and to VVI mode would be significative if there is an increase of at least 20%. SECONDARY ENDPOINT Secondary endpoint is bifocal stimulation therapy response, defined by at least one of the following criteria, evaluated at baseline, 6-months follow-up and 12 months-follow-up in comparison to baseline and VVI mode: NYHA functional class improvement; changes in 6MWT, defined by an increase in distance walked major or equal to 30%; LVEF improvement major or equal to 25%;Left ventricular telesystolic volume reduction major or equal to 15%
This prospective study aims to compare the diagnostic yield, or ability to detect an arrhythmia, of the traditional Holter monitor versus the novel Zio patch monitor in pediatric patients referred for ambulatory electrocardiographic (ECG) monitoring. Children will wear both devices simultaneously for 48 hours and the incidence of clinically significant arrhythmias will be compared.
The purpose of this study is to determine whether the transcutaneous application of unmodulated high frequency alternating currents could produce a quickly conduction block of peripheral nerve.
The purpose of this study is to characterize performance of the MARVEL algorithm downloaded into the MicraTM TPS to provide atrial synchronous ventricular pacing in subjects with AV block. A sub-study will be conducted within the Marvel study, the purpose of this study is to characterize the MARVEL algorithm in patients who were enrolled in the MARVEL study, and to collect and compare the accelerometer signals and AV synchrony at a second point in time.
The investigators sought to evaluate the morphological and functional changes, risk stratification and prognosis of patients of participants with compete left bundle branch block (CLBBB). The conduction of this study was largely due to the increased clinical requirement, which reflected the increased awareness among physicians of heart failure due to asynchronous cardiac function caused by CLBBB. The investigators also aim to figure out the time point or CMR parameters for cardiac resynchronization therapy in patients with CLBBB.