scholarly journals GW28-e1149 Three-dimensional reconstruction analysis of the esophagus, left atrium, and pulmonary veins: Implications for cryoablation of atrial fibrillation

2017 ◽  
Vol 70 (16) ◽  
pp. C121-C122
Author(s):  
GuiTang Yang ◽  
Wang Zulu ◽  
Xiao Junrui ◽  
Yang Benqiang ◽  
Sun Mingyu ◽  
...  
2003 ◽  
Vol 26 (1p1) ◽  
pp. 8-15 ◽  
Author(s):  
ALEJANDRO PEREZ‐LUGONES ◽  
PAULO R. SCHVARTZMAN ◽  
ROBERT SCHWEIKERT ◽  
PATRICK J. TCHOU ◽  
WALID SALIBA ◽  
...  

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Jürgen Biermann ◽  
Christoph Bode ◽  
Stefan Asbach

Accurate delineation of the variable left atrial anatomy is of utmost importance during anatomically based ablation procedures for atrial fibrillation targeting the pulmonary veins and possibly other structures of the atria. Intracardiac echocardiography allows real-time visualisation of the left atrium and adjacent structures and thus facilitates precise guidance of catheter-based ablation of atrial fibrillation. In patients with abnormal anatomy of the atria and/or the interatrial septum, intracardiac ultrasound might be especially valuable to guide transseptal access. Software algorithms like CARTOSound (Biosense Webster, Diamond Bar, USA) offer the opportunity to reconstruct multiple two-dimensional ultrasound fans generated by intracardiac echocardiography to a three-dimensional object which can be merged to a computed tomography or magnetic resonance imaging reconstruction of the left atrium. Intracardiac ultrasound reduces dwell time of catheters in the left atrium, fluoroscopy, and procedural time and is invaluable concerning early identification of potential adverse events. The application of intracardiac echocardiography has the great capability to improve success rates of catheter-based ablation procedures.


Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Georg Noelker ◽  
Stefan Asbach ◽  
Klaus Juergen Gutleben ◽  
Anil Sinha ◽  
Guido Ritscher ◽  
...  

Preprocedural imaging and its integration into electroanatomical mapping (EAM) is commonly used in atrial fibrillation (AF) ablation. However, intraprocedural imaging based on rotational angiography (DynaCT Cardiac) may be superior in terms of actuality and may lead to an improved work-flow. Feasibility of integrating Dyna CT Cardiac into EAM has not yet been shown. In 23 patients (62±7 years, 16 male) undergoing catheter ablation of paroxysmal (n=10) or persistent (n=13) AF, we intraprocedurally performed rotational angiography enhanced by contrast agent applied to the pulmonary artery with offline segmentation of left atrium (LA) and pulmonary veins (PV). Fig 1 depicts reconstructed LA and PV-anatomy directly importet into CARTOMerge. Distances between the 2 modalities were analyzed. Direct image integration of prereconstructed 3D-anatomy was feasible in all patients. Procedure time was 156 ± 24 minutes including 11 ± 3 minutes for DynaCT Cardiac registration and segmentation. 132 ± 74 mapping points were taken. Mapping points deviated to intraprocedural DynaCT Cardiac 3D-reconstructions by 2.2 ± 0.4 mm (2.3 ± 0.5 mm in patients suffering from paroxysmal atrial fibrillation (AF) vs. 2.1 ± 0.40 mm persistent AF, n.s.). No complications occured. Integration of intraprocedural Dyna CT Cardiac into EAM was feasible and fast. The work-flow seemed to be improved by avoiding additional preprocedural imaging. The novel modality is highly accurate in comparison to EAM.


Author(s):  
J. Frank ◽  
B. F. McEwen ◽  
M. Radermacher ◽  
C. L. Rieder

The tomographic reconstruction from multiple projections of cellular components, within a thick section, offers a way of visualizing and quantifying their three-dimensional (3D) structure. However, asymmetric objects require as many views from the widest tilt range as possible; otherwise the reconstruction may be uninterpretable. Even if not for geometric obstructions, the increasing pathway of electrons, as the tilt angle is increased, poses the ultimate upper limitation to the projection range. With the maximum tilt angle being fixed, the only way to improve the faithfulness of the reconstruction is by changing the mode of the tilting from single-axis to conical; a point within the object projected with a tilt angle of 60° and a full 360° azimuthal range is then reconstructed as a slightly elliptic (axis ratio 1.2 : 1) sphere.


Author(s):  
Nicolas Boisset ◽  
Jean-Christophe Taveau ◽  
Jean Lamy ◽  
Terence Wagenknecht ◽  
Michael Radermacher ◽  
...  

Hemocyanin, the respiratory pigment of the scorpion Androctonus australis is composed of 24 kidney shaped subunits. A model of architecture supported by many indirect arguments has been deduced from electron microscopy (EM) and immuno-EM. To ascertain, the disposition of the subunits within the oligomer, the 24mer was submitted to three-dimensional reconstruction by the method of single-exposure random-conical tilt series.A sample of native hemocyanin, prepared with the double layer negative staining technique, was observed by transmisson electron microscopy under low-dose conditions. Six 3D-reconstructions were carried out indenpendently from top, side and 45°views. The results are composed of solid-body surface representations, and slices extracted from the reconstruction volume.The main two characters of the molecule previously reported by Van Heel and Frank, were constantly found in the solid-body surface representations. These features are the presence of two different faces called flip and flop and a rocking of the molecule around an axis passing through diagonnally opposed hexamers. Furthermore, in the solid-body surface of the top view reconstruction, the positions and orientations of the bridges connecting the half molecules were found in excellent agreement with those predicted by the model.


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