Active clinical trials for "Heart Block"

This study is a long-term, prospective, and controlled evaluation of the mechanical dyssynchrony induced by right ventricular apical pacing, both in acute (spontaneous and stimulated) and chronic (12 and 24 months); the study also evaluates the benefit of an alternative pacing site through measures of dyssynchrony in acute and chronic.

The purpose of this study is to examine whether RV (right ventricular)septal pacing has any effect on LV ( left ventricular) function than RV apical pacing in patients who require ventricular pacing.

Unlike phones, which are commonly held to the ear, music is now available via portable MP3 players and they can be held almost anywhere. Thaker et al state that Apple iPods cause pacemaker interference in 50% of their patients, with over-sensing in 20% of patients, telemetry interference in 29% of patients and pacemaker inhibition in 1.2% of patients. The mean age for their sample was 76.1 years +/- 8.6 years. We anticipate that a higher proportion of teenagers and children who have pacemakers use portable MP3 players than in the elderly adult population.We will include the first 100 patients with pacemakers and ICDs who consent for the prospective observational study a single tertiary care center. We intend to conduct a descriptive study, tabulating the number of times that a pacemaker or ICD has changes in the sensing thresholds, pacing thresholds, telemetry interference or pacemaker inhibition when exposed to a series of portable MP3 players at various distances. In addition, we will describe the nature and quantitative differences of those changes.

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.

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.

This is a prospective observational study, the purpose of which is to: Characterize response of the AV conduction system to TAVR with various prostheses by recording continuous His bundle electrograms during valve placement. Correlate preprocedure ECG features with changes in AV nodal and infranodal conduction during placement of the valve prosthesis. Correlate changes in AV nodal and infranodal conduction during the procedure with risk of developing AV conduction block after TAVR. Assess the contribution of stressing the conduction system by atrial pacing prior to and following TAVR to prediction of postprocedural heart block. Assess the correlation between new onset bundle branch block, site and degree of conduction block or delay and subsequent development of high-grade or complete AV block.

A left bundle branch block (LBBB) is related to abnormal cardiac conduction and mechanical asynchrony and is associated with hypertension and coronary artery disease. Improved evaluation of left ventricular (LV) mechanical asynchrony is needed, because of the increasing number of patients with a LBBB and heart failure. A variety of patterns of mechanical activation can be observed in LBBB patients. Novel imaging modalities such as tissue Doppler imaging, real-time 3D echocardiography and cardiovascular magnetic resonance imaging provide information about regional and global LV function in healthy subjects, patients without a LBBB with heart failure, patients with a LBBB without heart failure, and patients with a LBBB with heart failure. The investigators want to evaluate the different patient groups with the novel imaging modalities and they want to compare the novel imaging modalities with each other. The investigators hypothesized that, between the groups, differences concerning regional and global LV function are measurable. Each novel imaging technique has its own advantages and limitations but are comparable in measuring regional and global LV function.

To construct a computerized database of national profiles and epidemiological data on patients wearing Medtronic implantable pacemakers and cardioverter defibrillators (both with or without cardiac resynchronization therapy), implantable loop recorders and leads used within their intended use. Clinical variables will be analyzed in relation to device-based data and diagnostics.

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.

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) .