A5007223065- Cardiac pacing and defibrillation studies
- Cardiac Arrhythmias and Treatments
- Cardiac electrophysiology and arrhythmias
- Cardiac Valve Diseases and Treatments
- Electrochemical Analysis and Applications
- Neuroscience and Neural Engineering
- Advanced Battery Technologies Research
- Fuel Cells and Related Materials
- EEG and Brain-Computer Interfaces
- Mechanical Circulatory Support Devices
- Atrial Fibrillation Management and Outcomes
- ECG Monitoring and Analysis
- Cardiac Arrest and Resuscitation
- Thyroid and Parathyroid Surgery
- Cardiovascular Function and Risk Factors
- Orthopaedic implants and arthroplasty
- Photoreceptor and optogenetics research
- Cardiomyopathy and Myosin Studies
- Gas Sensing Nanomaterials and Sensors
- Pharmaceutical studies and practices
- Analytical Methods in Pharmaceuticals
- Geophysics and Sensor Technology
- Cardiovascular Conditions and Treatments
- Cardiovascular Disease and Adiposity
- Cardiac Structural Anomalies and Repair
Medtronic (Ireland)
2015-2024
Rhythm (United states)
2024
Medtronic (United States)
1998-2022
St George's, University of London
2018
Coventry (United Kingdom)
2018
University of Alabama
2012
Case Western Reserve University
1992-2003
Permanent cardiac pacing is the only effective treatment for symptomatic bradycardia, but complications associated with conventional transvenous systems are commonly related to lead and pocket. We describe early performance of a novel self-contained miniaturized pacemaker. Patients having Class I or II indication VVI underwent implantation Micra transcatheter system, from femoral vein fixated in right ventricle using four protractible nitinol tines. Prespecified objectives were >85% freedom...
The introduction of transcatheter pacemaker technology has the potential to significantly reduce if not eliminate a number complications associated with traditional leaded pacing system. However, this raises new questions regarding how manage device at end service, devices right ventricle (RV) can accommodate, and what patient age is appropriate for therapy. In study, six human cadaver hearts one reanimated heart (not deemed viable transplant) were each implanted three Micra in locations via...
Two major studies have shown that leadless pacemakers are safe and effective for patients requiring right ventricular rate responsive pacing therapy. This positive result recently led to FDA approval of one the available devices. While this new technology is promising, it requires a different skill set implantation. In article, we review in detail steps required implantation tine-based while providing tips tricks minimize complications.
The Micra leadless pacemaker was developed to fit inside the right ventricle, thereby reducing overall complications by 48% compared with a historical control group. current labeling restricts implants femoral approach. In this article we used 3-dimensional computer models of human hearts demonstrate why can be difficult in small patients and how using jugular approach reduces these difficulties.
The miniaturized leadless pacemaker has recently emerged as a bradycardia therapy in humans, and many patients may need at least two pacemakers their lifetime. Thus, the present study assessed effect of right ventricle (RV) on cardiac function swine model.Fourteen mini pigs were chronically studied. Each animal received sequential RV with 1 month between separate implantations. All animals then followed for 6 months. Cardiac was echocardiography baseline, second implantation, end 6-month...
The Micra® Transcatheter Pacing System (TPS; Medtronic Inc., Minneapolis, MN, USA) is a miniaturized single-chamber pacemaker system that delivered via catheter through the femoral vein. In this study, electrical performance was compared between TPS and traditional leaded pacemaker. addition, safety profile of two systems by thorough monitoring for number adverse events.The implanted in right ventricular apex 10 Yucatan mini pigs single-lead (SLP) another connected to all devices monitored...
The purpose of this paper was to evaluate a nitinol tine fixation design for transcatheter pacemaker in order determine if the tines could be easily deployed and safely removed from myocardium, enable low, stable pacing thresholds, minimize potential dislodgment.The penetration properties 13 human hearts were compared deployment energy myocardium. safety factor dislodgement calculated by comparing kinetic device tines. stability tested 113 chronic implants across 89 animals via threshold...
The apparent low adverse effect profile of the new drug zafirlukast has made it an attractive choice in treatment asthma. We present first case (to our knowledge) a potentially serious drug-drug interaction between and theophylline. A 15-year-old white girl with asthma had been taking theophylline (Slo-bid, Rhone-Poulenc Rorer Pharmaceuticals Inc, Collegeville, Pa) (300 mg twice daily), levels approximately 61 micromol/L (11.0 microg/mL) for several years. Recently, her serum increased to...
Cardiac pacing is a critical technology for the treatment of arrhythmia and heart failure. The impact specific strategies on myocardial function an area intense research high clinical significance. Mouse models have proven extremely useful probing mechanisms disease, but there currently no reliable long-term in mouse.We sought to develop device studies mice. We evaluated (1) treating third-degree atrioventricular block after macrophage depletion, (2) ventricular pacing-induced...
Abstract The potentiometric and AC impedance characteristics of all solid‐state sodium‐selective electrodes based on planar screen‐printed Ag/AgCl are described. Two designs have been investigated. first was the deposition a PVC membrane directly top electrode. second design included NaCl doped hydrogel layer, between layers. provides mechanism to relieve any blockage charge transfer occurring when membranes used also improves adhesion two Results suggest display fast ion exchange kinetics,...
A pulse‐clamp method has been developed for measuring the electrochemical processes occurring on neural stimulating electrodes in 100 μs time frame of a typical stimulus pulse. By immediately following controlled current pulse with potential step back to prestimulus potential, we can measure reversal reversible reactions that occurred during Using this information then deduce reaction and how much charge went into each process. This employs an electronic instrument be operated (i) regulated...
The Medtronic Micra transcatheter pacing system (TPS) is a miniaturized VVIR pacemaker that less than one-tenth the volume of typical pacemaker, or 0.8 cc (6.7 mm diameter by 26 long). TPS small enough to place directly within right ventricle (RV) at site pacing, and uses 4 nitinol tines for fixation. Implanting entirely heart eliminates need both device pocket lead. lead contributed 75% 88% complications in 2 different reports.
In this article we present the extraction of a Micra from human cadaver implanted 3 years previously with both visual and X-ray imaging taken during removal.A pacemaker was extracted endoscopy fluoroscopy using delivery tool. Histological analysis performed on slices tissue surrounding Micra.The fully encapsulated easily retrieved maximum force 1.9 pounds.Even though almost previously, snaring relatively minimal required.
Background: Since their invention, cardiac pacemakers have provided significant lifesaving therapy for millions of people. However, a device small enough to be placed within the heart would eliminate pocket and lead thereby many modern pacemaker complications. We created 7-year VVIR with volume less than 1 cc that can directly heart. In this study, we assessed performance design by comparing pacing thresholds, R-wave amplitudes, impedances leadless prototypes using three separate methods...
Gold - Percent Total Charge 100 I . The Pulse-Clamp method, developed in this laboratory, was uscd to measure the quantity of unrecoverable charge as a function stimulus pulscwidlh and delay between stimulating reversing pulses on Pt Au electrodes. It found that both increasing dclay pulsc width caused increasc slightly metals. significance increase, particularly it relates tissuc damage, is currently unknown. effect may be greater whcn scrics pulse delivered. rate recovery decrcased with...
Pacemaker used in small children typically consist of an abdominally placed generator and epicardially affixed leads, making such a system prone to lead dysfunction during growth. Aim this study was investigate the feasibility epicardial pacing with leadless pacemaker lamb model.Seventeen lambs underwent implantation Micra transcatheter (TPS) (Medtronic, Minneapolis, MN, USA) via left-lateral thoracotomy left ventricle (LV) surface (n = 11/17) atrial appendage 6). Ventricular devices were...
The resistance during defibrillating pulses was measured on Medtronic patch electrodes in a saline tank. found to increase each phase of biphasic pulse, but the second always less than first resistance. This phenomenon explained by polarization electrode-solution interface. In fact, if voltage subtracted from measurement then changes were not seen.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
The objective of this paper is to determine if the electrode resistance for defibrillation electrodes with same shadow area changes exposed metal area. To accomplish was compared identical coil and without insulation between windings (backfill), solid cylinders dimensions as electrodes. results were that removing backfill reduced by 2%, an increase 400%. Similarly, cylinder 3% less than backfilled even though surface 300% larger. Thus increasing while keeping in a small but significant...
Lead Fixation in Dogs Achieved with RF Energy. Introduction : The purpose of this study was to test whether radiofrequency (RF) energy could be used fixate leads the endocardium. Methods and Results In six dogs we measured dislodgment force pacing threshold before after coronary sinus (CS) right ventricle (RV). fixation achieved a CardioRhythm Atakr* ablation unit. CS fixed 1.63 ± 0.65 oz, compared < 0.1 oz for similar placed separate dogs. RV, had 1.29 0.27 0.48 0.28 oz. urethane ( P...