View clinical trials related to Heart Block.
Filter by: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 clinical study has been designed to test whether a new pacing therapy would lead to improvement in heart function, symptoms and quality of life in a specific group of heart failure patients. This group has a unique electrical conduction problem (Right Bundle Branch Block) that did not respond well to the current available pacing therapy.
Purpose of the study: The goal of this study is to evaluate the relationship of electrocardiogram (ECG) findings with clinical outcomes in a cohort of patients with left bundle branch block (LBBB) who are being evaluated for acute coronary syndrome (ACS) in the Emergency Department (ED). Background and significance: The significance of specific ECG findings in patients with LBBB being evaluated for ACS has been inadequately studied, and this gap in knowledge is a barrier to optimal management of this population. Due to the speed, availability, low cost, and non-invasive nature of the ECG, it would be ideal to identify ECG characteristics that help to risk stratify these patients in order to inform clinical decision-making, reduce unnecessary invasive testing, and conserve resources. Methods: In this prospective observational study the investigators will identify a consecutive series of adult patients with LBBB presenting to the ED with suspicion of ACS. The investigators will collect data including demographics, cardiac risk factors, initial ECG measurements, lab and radiographic results, procedure results, and clinical outcomes such as 30-day death or myocardial infarction (MI). The investigators will analyze the data using a cohort study design to calculate odds ratios between ECG characteristics and the outcomes of interest.
This is a single center, non-randomized, unblinded study of patients who are followed at Essentia Health - St. Mary's Medical Center and who are referred for a clinically indicated diagnostic electrophysiology (EP) study with or without ablation. During the procedure, events of atrial fibrillation, sinus rhythm and bundle branch block that may occur during the course of the case will be saved electronically and analyzed offline. The stored data will be evaluated off-line for changes in activation timing of the near and far field ventricular signals of the stored events. This proof-of-concept study will attempt to assess whether atrial fibrillation, or bundle branch block can change activation timing compared to baseline sinus rhythm. If no significant activation change is seen, then this finding can be used as a basis to distinguish ventricular tachycardia from atrial fibrillation in future rhythm discrimination methods.
The purpose of this trial or study is to determine if pacemaker therapy can be a beneficial alternative to conventional medical therapy in patients with a history of moderate heart failure. The investigators are looking to enroll approximately 180 people in this trial. Patients will be randomized in two groups. One group will be implanted with a pacemaker and will continue to receive conventional medical therapy as prescribed by their doctor. The second group will continue to receive conventional medical therapy as prescribed by their doctor and will not be implanted with a pacemaker. Clinical histories, physical exams, and external device testing will be collected both at the time of enrollment in the trial and during follow-up study visits. Patients who enter the study will be seen for study visits at 1 month, 3 and 6 months.
The study aims to use cardiac MRI scans and analysis techniques to evaluate differences in cardiac function after 12 months of pacing in patients with pacing leads placed in different positions within the right ventricle (apically or septally).
Patients with implanted pacemakers are currently seen by their cardiologists every 6-12 months. Shorter follow-up intervals are generally seen as excessive workload for the physician, with little benefit for the patient. Longer intervals are seen as too dangerous concerning device integrity and safety. This scheme still results in a large number of follow-up visits with little or no important changes in pacemaker therapy. Our clinical trial investigates efficacy and safety of the Home Monitoring technology for increasing the flexibility in pacemaker follow-up. Home Monitoring technology allows automatic transmission via mobile phone links of relevant data from the implanted pacemaker to a service center. The patient's physician can access the data via a password-protected internet site. The regular Home Monitoring data analyses entirely replace clinical routine visits ("virtual clinic"). Follow-up visits are scheduled according to the results of the Home Monitoring data analyses. The primary endpoint of the study is to compare the total workload for pacemaker patient care in the virtual clinic with that of standard follow-up scheme with regularly scheduled clinical visits.
We would like to conduct a retrospective chart review examining the incidence of surgical heart block in children treated in the Cardiac Service Line at Children's Healthcare of Atlanta. We would like to look at the last 30 surgical heart block cases seen at Children's Healthcare of Atlanta. We will collect the following information on each patient: Patient Date of Birth Date of the surgical procedure Weight of the patient at the time of surgery Concomitant Diagnoses Need for permanent pacemaker Outcome of pacing (i.e. pacing successful) We hope to look at each data element in order to determine potential risks factors for surgical heart block. By identifying the risk factors, the investigator hopes to establish a training program regarding surgical avoidance of certain areas of the heart (if possible) and education regarding pacemaker follow-up. Each patient will be given a unique study number. The patient's name, social security number, medical record number or initials will not be used in our research database.