Background: The optimal waveform tilt for defibrillation is not known. Most modern defibrillators used for the cardioversion of atrial fibrillation (AF) employ high-tilt, capacitor-based biphasic waveforms.
Methods: We have developed a low-tilt biphasic waveform for defibrillation. This low-tilt waveform was compared with a conventional waveform of equivalent duration and voltage in patients with AF. Patients with persistent AF or AF induced during a routine electrophysiology study (EPS) were randomized to receive either the low-tilt waveform or a conventional waveform. Defibrillation electrodes were positioned in the right atrial appendage and distal coronary sinus. Phase 1 peak voltage was increased in a stepwise progression from 50 V to 300V. Shock success was defined as return of sinus rhythm for >/=30 seconds.
Results: The low-tilt waveform produced successful termination of persistent AF at a mean voltage of 223 V (8.2 J) versus 270 V (6.7 J) with the conventional waveform (P = 0.002 for voltage, P = ns for energy). In patients with induced AF the mean voltage for the low-tilt waveform was 91V (1.6 J) and for the conventional waveform was 158 V (2.0 J) (P = 0.005 for voltage, P = ns for energy). The waveform was much more successful at very low voltages (less than or equal to 100 V) compared with the conventional waveform (Novel: 82% vs Conventional 22%, P = 0.008).
Conclusion: The low-tilt biphasic waveform was more successful for the internal cardioversion of both persistent and induced AF in patients (in terms of leading edge voltage).
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http://dx.doi.org/10.1111/j.1540-8159.2008.01129.x | DOI Listing |
Sci Rep
January 2025
Department of Electrical and Computer Engineering, University of Waterloo, Waterloo, ON, Canada.
The integration of radar technology into smart furniture represents a practical approach to health monitoring, circumventing the concerns regarding user convenience and privacy often encountered by conventional smart home systems. Radar technology's inherent non-contact methodology, privacy-preserving features, adaptability to diverse environmental conditions, and high precision characteristics collectively establish it a compelling alternative for comprehensive health monitoring within domestic environments. In this paper, we introduce a millimeter (mm)-wave radar system positioned strategically behind a seat, featuring an algorithm capable of identifying unique cardiac waveform patterns for healthy subjects.
View Article and Find Full Text PDFUltrasonics
January 2025
Department of Civil Engineering and Architecture, Tallinn University of Technology, Ehitajate tee 5, 19086, Tallinn, Estonia. Electronic address:
Pipe bends are recognized as critical areas susceptible to wall thinning, a phenomenon instigated by abrupt changes in the fluid flow direction and velocity. Conventional monitoring techniques for bends typically depend on localized ultrasonic measurements of thickness. While these methods are effective, they can be time-consuming compared to the use of permanently installed transducers, a strategy employed in guided wave tomography (GWT).
View Article and Find Full Text PDFBiomed Phys Eng Express
January 2025
Department of Neurology and Neurological Sciences, Stanford Medicine, 213 Quarry Road, Palo Alto, California, 94305-5101, UNITED STATES.
Clinical adoption of innovative EEG technology is contingent on the non-inferiority of the new devices relative to conventional ones. We present the four key results from testing the signal quality of Zeto's WR19 EEG system against a conventional EEG system conducted on patients in a clinical setting. Methods: We performed 30-minute simultaneous recordings using the Zeto WR19 (zEEG) and a conventional clinical EEG system (cEEG) in a cohort of 15 patients.
View Article and Find Full Text PDFLight Sci Appl
January 2025
Yildiz Technical University, Faculty of Chemical and Metallurgical Engineering, Department of Metallurgical and Materials Engineering, Glass Research and Development Laboratory, Istanbul, 34220, Türkiye.
Three-dimensional (3D) imaging technology holds immense potential across various high-tech applications; however, current display technologies are hindered by limitations such as restricted viewing angles, cumbersome headgear, and limited multi-user accessibility. To address these challenges, researchers are actively exploring new materials and techniques for 3D imaging. Laser-based volumetric displays (VDs) offer a promising solution; nonetheless, existing screen materials fall short in meeting key requirements for long-term durability, full-color operation, and scalability.
View Article and Find Full Text PDFEpilepsia
December 2024
Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA.
Objective: The most common medically resistant epilepsy (MRE) involves the temporal lobe (TLE), and children designated as temporal plus epilepsy (TLE+) have a five-times increased risk of postoperative surgical failure. This retrospective, blinded, cross-sectional study aimed to correlate visual and computational analyses of magnetoencephalography (MEG) virtual sensor waveforms with surgical outcome and epilepsy classification (TLE and TLE+).
Methods: Patients with MRE who underwent MEG and iEEG monitoring and had at least 1 year of postsurgical follow-up were included in this retrospective analysis.
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