A novel octaray multielectrode catheter for high‐resolution atrial mapping: Electrogram characterization and utility for mapping ablation gaps

2019 ◽  
Vol 30 (5) ◽  
pp. 749-757 ◽  
Author(s):  
Jakub Sroubek ◽  
Markus Rottmann ◽  
Michael Barkagan ◽  
Eran Leshem ◽  
Ayelet Shapira‐Daniels ◽  
...  
Keyword(s):  
High Resolution ◽  
Atrial Mapping

Abstract 16342: Feasibility and Safety of Intra-operative Mapping for Diagnosis of the Substrate of Atrial Fibrillation

Circulation ◽  
2015 ◽  
Vol 132 (suppl_3) ◽  
Author(s):  
Lisette van der Does ◽  
Ameetha Yaksh ◽  
Charles Kik ◽  
Paul Knops ◽  
Frans Oei ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Mean Arterial Pressure ◽  
High Resolution ◽  
Arterial Pressure ◽  
Right Atrial ◽  
Epicardial Mapping ◽  
High Resolution Mapping ◽  
Mapping Approach ◽  
Resolution Mapping ◽  
Atrial Mapping

Introduction: Multi-site, high-resolution mapping can be used to identify either the trigger or substrate perpetuating atrial fibrillation (AF). The goal of this study was to assess the feasibility and safety of a new high-resolution epicardial mapping approach. Hypothesis: Epicardial atrial mapping of the entire atria can be safely performed as a routine procedure during cardiac surgery. Methods: Epicardial mapping of the entire right atrium, left atrium and Bachmann’s Bundle was performed in 291 patients (218 male, age:66±11yrs) undergoing elective surgery during sinus rhythm (SR) and (induced) AF using high-resolution mapping arrays with inter-electrode distances of 1-2mm. Electrophysiological parameters were quantified and designated to anatomical quadrants of 1cm2. Results: AF was non-inducible in 36 patients. Hemodynamic parameters (mean arterial pressure, right atrial pressure, BIS score, ST-T segment alterations) before and during SR mapping were comparable (P<0.22). During AF, only mean arterial pressure (71±11 versus 67±10mmHg (P<0.004)) and right atrial pressure (10±4 versus 11±4mmHg (P<0.0001)) decreased. Total mapping time during SR or AF was respectively 3±1min. and 4±2min. Beat-to-beat variation of SR cycle length and peak-to-peak amplitude of unipolar potentials were respectively 0.04±14.42ms and -0.01±0.53mV, reflecting stability of the mapping array. Complications were not observed. Conclusions: Our novel intra-operative epicardial atrial mapping approach can be safely applied during both SR and AF. This mapping approach is the first technique allowing quantification of the arrhythmogenic substrate in the individual patient thereby taking the first step towards personalizing treatment of AF.

scholarly journals A novel intra-operative, high-resolution atrial mapping approach

2015 ◽  
Vol 44 (3) ◽  
pp. 221-225 ◽  
Author(s):  
Ameeta Yaksh ◽  
Lisette JME van der Does ◽  
Charles Kik ◽  
Paul Knops ◽  
Frans BS Oei ◽  
...  
Keyword(s):  
High Resolution ◽  
Mapping Approach ◽  
Atrial Mapping

scholarly journals B-PO04-081 IMPROVED ACCURACY OF COMPLEX ATRIAL MAPPING USING CLOSE-UNIPOLAR ELECTROGRAMS IN A NOVEL ULTRA-HIGH RESOLUTION CATHETER MAPPING SYSTEM

Heart Rhythm ◽  
2021 ◽  
Vol 18 (8) ◽  
pp. S312
Author(s):  
Hiroshi Nakagawa ◽  
Shunsuke Kuroda ◽  
Assaf Govari ◽  
Christopher T. Beeckler ◽  
Vadim Gliner ◽  
...  
Keyword(s):  
High Resolution ◽  
Catheter Mapping ◽  
Mapping System ◽  
Improved Accuracy ◽  
Unipolar Electrograms ◽  
Atrial Mapping

Observations of the spatial structure of interstellar hydrogen

1967 ◽  
Vol 31 ◽  
pp. 45-46
Author(s):  
Carl Heiles
Keyword(s):  
High Resolution ◽  
Spatial Structure ◽  
Velocity Dispersion ◽  
Temperature Variations

High-resolution 21-cm line observations in a region aroundlII= 120°,b11= +15°, have revealed four types of structure in the interstellar hydrogen: a smooth background, large sheets of density 2 atoms cm-3, clouds occurring mostly in groups, and ‘Cloudlets’ of a few solar masses and a few parsecs in size; the velocity dispersion in the Cloudlets is only 1 km/sec. Strong temperature variations in the gas are in evidence.

Combining integrated systems-biology approaches with intervention-based experimental design provides a higher-resolution path forward for microbiome research

2019 ◽  
Vol 42 ◽  
Author(s):  
J. Alfredo Blakeley-Ruiz ◽  
Carlee S. McClintock ◽  
Ralph Lydic ◽  
Helen A. Baghdoyan ◽  
James J. Choo ◽  
...  
Keyword(s):  
Systems Biology ◽  
High Resolution ◽  
Experimental Design ◽  
Integrated Systems ◽  
Microbiome Research ◽  
Constructive Criticism

Abstract The Hooks et al. review of microbiota-gut-brain (MGB) literature provides a constructive criticism of the general approaches encompassing MGB research. This commentary extends their review by: (a) highlighting capabilities of advanced systems-biology “-omics” techniques for microbiome research and (b) recommending that combining these high-resolution techniques with intervention-based experimental design may be the path forward for future MGB research.

Very High Resolution Analysis of the Dynamics of a Coronal Plasmoid

1994 ◽  
Vol 144 ◽  
pp. 593-596
Author(s):  
O. Bouchard ◽  
S. Koutchmy ◽  
L. November ◽  
J.-C. Vial ◽  
J. B. Zirker
Keyword(s):  
High Resolution ◽  
Solar Eclipse ◽  
Total Solar Eclipse ◽  
Field Of View ◽  
Small Field ◽  
High Resolution Analysis ◽  
Ccd Observations ◽  
Resolution Analysis ◽  
Very High ◽  
Small Field Of View

AbstractWe present the results of the analysis of a movie taken over a small field of view in the intermediate corona at a spatial resolution of 0.5“, a temporal resolution of 1 s and a spectral passband of 7 nm. These CCD observations were made at the prime focus of the 3.6 m aperture CFHT telescope during the 1991 total solar eclipse.

FeXIV Line Emission Polarization of the July 11, 1991 Solar Corona

1994 ◽  
Vol 144 ◽  
pp. 541-547
Author(s):  
J. Sýkora ◽  
J. Rybák ◽  
P. Ambrož
Keyword(s):  
High Resolution ◽  
Solar Corona ◽  
Emission Line ◽  
Solar Eclipse ◽  
White Light ◽  
Preliminary Analysis ◽  
Line Emission ◽  
Total Solar Eclipse ◽  
Degree Of Polarization ◽  
High Resolution Images

AbstractHigh resolution images, obtained during July 11, 1991 total solar eclipse, allowed us to estimate the degree of solar corona polarization in the light of FeXIV 530.3 nm emission line and in the white light, as well. Very preliminary analysis reveals remarkable differences in the degree of polarization for both sets of data, particularly as for level of polarization and its distribution around the Sun’s limb.

Microcalorimeters for X-Ray Spectroscopy

1988 ◽  
Vol 102 ◽  
pp. 41
Author(s):  
E. Silver ◽  
C. Hailey ◽  
S. Labov ◽  
N. Madden ◽  
D. Landis ◽  
...  
Keyword(s):  
High Resolution ◽  
High Efficiency ◽  
Thermal Response ◽  
Low Noise ◽  
High Resolution Spectroscopy ◽  
Superconducting Transition ◽  
Sapphire Substrates ◽  
Laboratory Plasmas ◽  
Adiabatic Demagnetization ◽  
Theoretical Predictions

The merits of microcalorimetry below 1°K for high resolution spectroscopy has become widely recognized on theoretical grounds. By combining the high efficiency, broadband spectral sensitivity of traditional photoelectric detectors with the high resolution capabilities characteristic of dispersive spectrometers, the microcalorimeter could potentially revolutionize spectroscopic measurements of astrophysical and laboratory plasmas. In actuality, however, the performance of prototype instruments has fallen short of theoretical predictions and practical detectors are still unavailable for use as laboratory and space-based instruments. These issues are currently being addressed by the new collaborative initiative between LLNL, LBL, U.C.I., U.C.B., and U.C.D.. Microcalorimeters of various types are being developed and tested at temperatures of 1.4, 0.3, and 0.1°K. These include monolithic devices made from NTD Germanium and composite configurations using sapphire substrates with temperature sensors fabricated from NTD Germanium, evaporative films of Germanium-Gold alloy, or material with superconducting transition edges. A new approache to low noise pulse counting electronics has been developed that allows the ultimate speed of the device to be determined solely by the detector thermal response and geometry. Our laboratory studies of the thermal and resistive properties of these and other candidate materials should enable us to characterize the pulse shape and subsequently predict the ultimate performance. We are building a compact adiabatic demagnetization refrigerator for conveniently reaching 0.1°K in the laboratory and for use in future satellite-borne missions. A description of this instrument together with results from our most recent experiments will be presented.

Radiation Damage, Contrast and Statistics in High Resolution Biological Electron Microscopy

1970 ◽  
Vol 28 ◽  
pp. 260-261
Author(s):  
Robert M. Glaeser
Keyword(s):  
High Resolution ◽  
Particle Flux ◽  
Unit Area ◽  
Signal To Noise ◽  
Resolution Image ◽  
High Resolution Image ◽  
Pass Through ◽  
Counting Statistics ◽  
The Relationship ◽  
Picture Element

It is well known that a large flux of electrons must pass through a specimen in order to obtain a high resolution image while a smaller particle flux is satisfactory for a low resolution image. The minimum particle flux that is required depends upon the contrast in the image and the signal-to-noise (S/N) ratio at which the data are considered acceptable. For a given S/N associated with statistical fluxtuations, the relationship between contrast and “counting statistics” is s131_eqn1, where C = contrast; r2 is the area of a picture element corresponding to the resolution, r; N is the number of electrons incident per unit area of the specimen; f is the fraction of electrons that contribute to formation of the image, relative to the total number of electrons incident upon the object.

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