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Stent Size (stent + size)
Selected AbstractsCoronary stent assessability by 64 slice multi-detector computed tomographyCATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 7 2007Tej Sheth MD Abstract Background: We evaluated the assessability of contemporary stent platforms by 64-slice multi-detector computed tomography (MDCT). Methods. Patients undergoing coronary stenting were included in a prospective protocol of MDCT imaging within 48 hr of stent implantation. MDCT data were acquired using a "Sensation 64" MDCT scanner (Siemens Medical Solutions, Forchheim, Germany). Stent assessability was assessed by two independent blinded observers and disagreement was resolved by a third observer. Assessability was defined at visualization of the in-stent lumen without influence of partial volume effects, beam hardening, motion, calcification, or contrast to noise limitations. Results: Fifty four stents (Cypher n = 25, Vision/Minivision n = 19, Taxus Express n = 8, Liberte n = 1, Driver n = 1) in 44 patients were included in the study. The two independent observers classified 30 of 54 stents (56%) as assessable. Interobserver reproducibility was good with , = 0.66. Stent size was the most important determinant of assessability. Consistently assessable stents were 3.0 mm or larger (85%), whereas those under 3 mm were mostly nonassessable (26%).Conclusions: Contemporary stent designs evaluated on a 64-slice MDCT scanner showed artifact free assessability only in larger stents. Increase in spatial resolution of MDCT scanners or modifications in stent design will be necessary to noninvasive evaluate stents <3 mm in diameter, where in-stent restenosis is more frequent. © 2007 Wiley-Liss, Inc. [source] Usefulness of multidetector CT imaging to assess vascular stents in children with congenital heart disease: An in vivo and in vitro study,CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 4 2008Joachim G. Eichhorn MD Abstract Objective: To evaluate varying CT settings to visualize pediatric vascular stents in comparison to digital angiography (DA). Background: There is a great clinical interest in substituting noninvasive methods to follow up children with congenital heart disease after interventional treatment. Materials and Methods: CT studies in small children with transcatheter placed stents were reviewed, retrospectively. Furthermore, eight stents were implanted in tubes and partially obstructed. CT exams were performed on varying scanners (4 up to 64 slices) with corresponding tube settings. The effects of dose on image quality were evaluated regarding stent size, strut thickness, and in-stent stenoses in comparison to DA. Results: Fourteen children with 28 implanted stents were identified. Significant differences between higher and lower radiation settings were not found, corresponding with the phantom, where moderate tube setting showed the best results. In vitro, there was an improvement with increasing number of detector rows, which resulted in a decrease of stent strut overestimation (295% down to 201%; P < 0.0001) and a better agreement with DA measurements for mild (78% up to 91%; P = 0.003) and moderate in-stent stenoses (80% up to 99%; P = 0.0001). Conclusion: Higher radiation exposure settings did not improve image quality, suggesting that the exams could be performed at a lower radiation dose. © 2008 Wiley-Liss, Inc. [source] Clinical assessment of a new real time 3D quantitative coronary angiography system: Evaluation in stented vessel segmentsCATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 1 2006Rainer Gradaus MD Abstract Background: Foreshortening is a recognized problem that is present in angiography and results from views that are not perpendicular to coronary lesions. This limits visual coronary analysis as well as 2D quantitative coronary angiography systems (QCA). The CardiOp-B System® is a 3D image acquisition and processing software system designed as an add-on to conventional X-ray angiography system. CardiOp-B's features include real time and off line analysis with comprehensive 3D reconstruction integrating all of the available information of two 2D vessel angiographies into one 3D image. It was the aim of the study to analyze the accuracy of this new 3D QCA system. Methods: 3D QCA was performed in 50 patients (age 64 ± 10.9; 84% male; LV-EF 63 ± 16%) measuring 61 stents during high-pressure inflation (diameter: 2.25,4 mm; length: 8,32 mm). The obtained values (proximal and distal stent diameter, stent length) were correlated with the predefined size of the stents at the used inflation pressure. Results: The linear correlation for the proximal stent diameter was Stentprox= 0.03 + 0.93 × real stent size (r2 = 0.85). The linear correlation for the distal stent diameter was Stentdistal= ,0.03 + 0.89 × real stent size (r2 = 0.81). The linear correlation for the stent length was Stentlength= ,0.61 + 1.02 × real stent length (r2 = 0.98). Conclusions: The CardiOp-B System® is a new 3D QCA system with a high linear correlation between the real vessel size and the obtained vessel dimension. It provides real time or off line accurate and comprehensive diagnostic information to the interventional cardiologist without changing the basic coronary angiography procedure. © 2006 Wiley-Liss, Inc. [source] Immediate and late clinical and angiographic outcomes after GFX coronary stenting: Is high-pressure balloon dilatation necessary?CLINICAL CARDIOLOGY, Issue 8 2000Ph.D., Seong-Wook Park M.D. Abstract Background: The GFX stent is a balloon-expandable stent made of sinusoidal element of stainless steel. The adjunct high-pressure balloon dilatations were usually recommended in routine stenting procedure. Hypothesis: The aim of this study was to evaluate the immediate and long-term clinical and angiographic outcomes and to investigate the necessity of high-pressure balloon dilatation during GFX stenting. Methods: In all, 172 consecutive patients underwent single 12 or 18 mm GFX stent implantation in 188 native coronary lesions. Two types of stenting technique were used: (1) stent size of a final stent-to-artery ratio of 1:1 (inflation pressure > 10 atm, high-pressure group), and (2) stent size of 0.5 mm bigger than reference vessel (inflation pressure , 10 atm, low-pressure group). The adjunct high-pressure balloon dilatations were performed only in cases of suboptimal results. Results: The adjunct high-pressure balloon dilatation was required in 11 of 83 lesions (13%) in the high-pressure group and in 7 of 105 lesions (7%) in the low-pressure group (p = 0.203). Procedural success rate was 100%. There were no significant differences of in-hospital and long-term clinical events between the two groups. The overall angiographic restenosis rate was 17.7%; 18.4% in the high-pressure group and 17.1% in the low-pressure group (p = 0.991). Conclusions: The GFX stent is a safe and effective device with a high procedural success rate and favorable late clinical outcome for treatment of native coronary artery disease. Further randomized trials may be needed to compare stenting techniques in GFX stent implantation. [source] | ||||||||||