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Aims Three-dimensional rotational angiography (3DRA) of the left atrium (LA) and the esophagus is a simple and safe method for analyzing the relationship between the esophagus and the LA during catheter ablation of atrial fibrillation. The purpose of this study is to describe the location of the esophagus relative to the LA and mobility of the esophagus during ablation procedure. Methods From 3/2011 to 9/2015, 3DRA of the LA and esophagus was performed in 326 patients before catheter ablation of atrial fibrillation. 3DRAwas performed with visualization of the esophagus via peroral administration of a contrast agent. The positions of the esophagus were determined at the beginning of the procedure, for part of patients also at the end of procedure with contrast esophagography. Results The most frequent position is behind the center of the LA (91 pts., 31.9%) The least frequent position is behind the right pulmonary veins (27 pts., 9.4%). The average shift of the esophagus position was 3.36 ± 2.15 mm, 3.59 ± 2.37 mm and 3.67 ± 3.23 mm for superior, middle and inferior segment resp. Conclusions The position of the esophagus to the LA is highly variable. The most common position of the esophagus relative to the LA is behind the middle and left part of the posterior wall of the LA. The least frequently observed position is behind the right pulmonary veins. No significant position change of esophagus motion from before to after the ablation procedure in the majority (≥95%) of the patients was observed.
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Objective: To investigate the safety and effectiveness of three-dimensional (3-D) rotational angiography reconstruction of left atrial and pulmonary vein stereo image embedded with real-time X-ray fluoroscopy system for guiding radiofrequency catheter ablation (RFCA) in treating the patients with atrial ifbrillation (AF). Methods: A total of 60 consecutive AF patients who received RFCA in our hospital from 2011-04 to 2013-04 were studied. The patients were randomly divided into 2 groups and 3-D Carto3 mapping system was applied for guiding RFCA in both groups. n=30 in each group. Treatment group, the patients received Siemens ARTIS Zeego digital subtraction system for left atrial and pulmonary vein rotational angiography, then, stereo images were reconstructed and embedded with real-time X-ray lfuoroscopy for RFCA guidance. Control group, conventional left and right pulmonary venography was conducted for RFCA guidance. The procedural and X-ray exposure times, rates of success and complications were recorded and compared between 2 groups. Results: All 60 patients had successful RFCA, compared with Control group, the patients in Treatment group had obviously less procedural time and X-ray exposure time, while the success rate and complications were similar between 2 groups. Conclusion: 3-D rotational angiography reconstruction of left atrial and pulmonary vein stereo image embedded with real-time X-ray lfuoroscopy system is safe and effective for guiding RFCA in treating the AF patients, which may reduce the procedural and X-ray exposure times.
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OBJECTIVE: Several modalities are available for volumetric measurement of the intracranial aneurysm. We discuss the challenges involved in manual segmentation, and analyze the application of alternative methods using automatic segmentation and geometric formulae in measurement of aneurysm volumes and coil packing density. METHODS: The volumes and morphology of 38 aneurysms treated with endovascular coiling at a single center were measured using three-dimensional rotational angiography (3DRA) reconstruction software using automatic segmentation. Aneurysm volumes were also calculated from their height, width, depth, size of neck, and assumed shape in 3DRA images using simple geometric formulae. The aneurysm volumes were dichotomized as "small" or "large" using the median volume of the studied population (54 mm3) measured by automatic segmentation as the cut-off value for further statistical analysis. RESULTS: A greater proportion of aneurysms were categorized as being "small" when geometric formulae were applied. The median aneurysm volumes obtained were 54.5 mm3 by 3DRA software, and 30.6 mm3 using mathematical equations. An underestimation of aneurysm volume with a resultant overestimation in the calculated coil packing density (p = 0.002) was observed. CONCLUSION: Caution must be exercised in the application of simple geometric formulae in the management of intracranial aneurysms as volumes may potentially be underestimated and packing densities falsely elevated. Future research should focus on validation of automatic segmentation in volumetric measurement and improving its accuracy to enhance its application in clinical practice.
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Aneurysm , Angiography , Intracranial Aneurysm , NeckABSTRACT
Introducción La angiografía convencional (AC) es la técnica de referencia para el diagnóstico de la enfermedad coronaria. Sin embargo, requiere múltiples proyecciones ortogonales para determinar el grado de enfermedad. La técnica de angiografía rotacional dual (ARD) permite una única adquisición e inyección de contraste para cada coronaria, con potencial reducción del volumen de contraste y de la dosis de radiación. Objetivo Comparar ambas técnicas (AC vs. ARD) a través de la evaluación de cantidad de contraste, exposición a la radiación y eficiencia diagnóstica. Material y métodos El presente es un estudio prospectivo, consecutivo, autocontrolado de coronariografías electivas para comparar AC y ARD. Todas las angiografías fueron revisadas por dos hemodinamistas independientes (observador 1 y observador 2) para evaluar la concordancia entre ambos tipos de imágenes. Para prevenir un sesgo en la lectura de las imágenes, los observadores evaluaron primero las ARD y tres semanas más tarde hicieron lo propio con las AC. Resultados Con la ARD se observó una reducción en la utilización de contraste (33,29 ± 11,2 ml vs. 17 ± 5,4 ml; p < 0,01) y en la exposición a radiación del paciente (235,6 ± 76,8 mGy vs. 82,7± 46,6 mGy; p < 0,01) y del operador (5,7 ± 3,26 mSv vs. 2,48 ± 1,47 mSv; p < 0,04). Se observó una leve diferencia y una fuerte correlación en el número de lesiones, diámetro del vaso y porcentaje de estenosis entre ambos observadores y entre ambos métodos. La evaluación categórica del porcentaje de estenosis también demostró una concordancia adecuada. Conclusión La ARD reduce el uso de contraste y la exposición a radiación en comparación con la técnica convencional, sin alterar la eficiencia diagnóstica del estudio.
Efficacy and safety of dual-axis rotational coronary angiography versus conventional angiography Background Conventional coronary angiography (CA) is the gold standard for the diagnosis of coronary artery disease. However, this technique requires several orthogonal projections to determine the severity of the disease. Dual-axis rotational coronary angiography (DARCA) is a new technique which allows visualization of each coronary artery using a single contrast injection and obtains unique images. This technique has been shown to reduce both radiation and contrast exposure. Objective To determine the amount of contrast used, radiation exposure and diagnostic accuracy of DARCA compared to conventional CA. Methods We conducted a prospective, self-controlled study of consecutive patients undergoing elective coronary angiography to compare DARCA versus the conventional technique. All the angiographies were reviewed by two independent interventional cardiologists (observer 1 and observer 2) who evaluated agreement between both types of images. The observers evaluated firstly the DARCAs and three weeks later the conventional CAs to prevent bias in reading the images. Results The contrast volume used in the diagnostic procedure was significantly lower with DARCA (33.29±11.2 ml vs. 17±5.4 ml; p <0.01). Radiation exposure in patient (235.6±76.8 mGy vs. 82.7±46.6 mGy; p <0.01) and operator was also significantly lower (5.7±3.26 mSv vs. 2.48±1.47 mSv; p <0.04). A slight difference and a strong correlation were seen in the number of lesions, vessel diameter and percentage of stenosis between both observers and in both methods. Agreement for categorizing percentage of stenoses was also adequate. Conclusion DARCA reduces the use of contrast agent and radiation exposure compared to the conventional technique without modifying the diagnostic accuracy of the method.
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PURPOSE: The neck angle is the novel geometric index that quantifies the aneurismal neck on cross sectional images. We characterized the morphology of aneurysms by the neck angle measured in the cross-sectional analysis of three-dimensional rotational angiography (3DRA). MATERIALS AND METHODS: A total of 62 patients with 69 sidewall aneurysms was included in the study. Cross sectional images were acquired in the perpendicular planes of the axis of parent arteries by use of 3DRA, and the degree of parent artery involvement by the aneurysm ostium defined as neck angle. The neck angles of the aneurysms were categorized into four groups as follows: narrow ( 115degrees). The cross sectional morphology of aneurysms in each group was evaluated. We obtained geometric indices of the sidewall aneurysms on 3DRA, including the width to neck ratio, aspect ratio, bottleneck ratio, depth to diameter of parent ratio (D/Dpa); and height to diameter of the parent ratio (H/Dpa). We evaluated the relationship between the neck angle and additional determined geographic indices in each case (Pearson's correlation). RESULTS: The neck angle was linearly related with the aneurysm-to-parent vessel size ratios (D/Dpa and H/Dpa) (p < 0.05). With increasing neck angle, the parent artery became deformed and indistinguishable from aneurismal ostium. CONCLUSION: The neck angle is a geometric index that demonstrates the morphologic relationship between aneurysm and parent artery. The cross sectional images of intracranial aneurysms can provide important information for characterization of aneurysms.