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Coronary Lumen (coronary + lumen)
Selected AbstractsHigh-frequency vibration for the recanalization of guidewire refractory chronic total coronary occlusions,CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 6 2008Klaus Tiroch MD Abstract Background: Recanalization of coronary chronic total occlusions (CTOs) remains a clinical challenge, particularly when standard guidewire attempts fail. Objectives: We sought to determine the safety and efficacy of a novel method that used high-frequency (20 kHz) vibration to fragment occlusive fibrous tissue and facilitate guidewire crossing into the distal vessel. Methods: A total of 125 patients with CTO, who failed at attempts of conventional guidewire recanalization after more than 5 min of fluoroscopy time, were enrolled in the study. The primary efficacy endpoint was the advancement of the CROSSERÔ catheter through the occlusion and attainment of coronary guidewire positioning in the distal coronary lumen. The primary safety endpoint was the occurrence of death, myocardial infarction, clinical perforation, or target vessel revascularization within the first 30 days. Results: The average fluoroscopy time while delivering the CROSSER catheter was 12.4 min. CROSSER-assisted guidewire recanalization was achieved in 76 (60.8%) procedures and a final diameter stenosis <50% was obtained in 68 (54.4%) of cases. Major adverse events occurred in 11 (8.8%) patients, lower than the predefined objective performance criteria. Angina frequency and quality of life were improved in patients with successful guidewire recanalization. Conclusions: We conclude that high-frequency vibration using the CROSSER catheter is a safe and effective therapy for patients with CTO, which are refractory to standard guidewire recanalization. © 2008 Wiley-Liss, Inc. [source] Current status of rotational atherectomyCATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 4 2004Erdal Cavusoglu MD Abstract Despite the increasing use of percutaneous transluminal coronary angioplasty and intracoronary stent placement for the treatment of obstructive coronary artery disease, a large subset of coronary lesions cannot be adequately treated with balloon angioplasty and/or intracoronary stenting alone. Such lesions are often heavily calcified or fibrotic and undilatable with the present balloon technology and attempts to treat them with balloon angioplasty or intracoronary stent placement often lead to vessel dissection or incomplete stent deployment with resultant adverse outcomes. Rotational atherectomy remains a useful niche device for the percutaneous treatment of such complex lesions, usually as an adjunct to subsequent balloon angioplasty and/or intracoronary stent placement. In contrast to balloon angioplasty or stent placement that widen the coronary lumen by displacing atherosclerotic plaque, rotational atherectomy removes plaque by ablating the atherosclerotic material, which is dispersed into the distal coronary circulation. Other lesion subtypes amenable to treatment with this modality include ostial and branch-ostial lesions, chronic total occlusions, and in-stent restenosis. This review discusses the technique and principles of rotational atherectomy, the various treatment strategies for its use (including adjunctive pharmacotherapy), the lesion-specific applications for this device, and the complications unique to this modality. Recommendations are also made for its use in the current interventional era. Catheter Cardiovasc Interv 2004;62:485,498. © 2004 Wiley-Liss, Inc. [source] Reproducibility of coronary lumen, plaque, and vessel wall reconstruction and of endothelial shear stress measurements in vivo in humansCATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 1 2003Ahmet U. Coskun PhD Abstract The purpose of this study was to assess the reproducibility of an in vivo methodology to reconstruct the lumen, plaque, and external elastic membrane (EEM) of coronary arteries and estimate endothelial shear stress (ESS). Ten coronary arteries without significant stenoses (five native and five stented arteries) were investigated. The 3D lumen and EEM boundaries of each coronary artery were determined by fusing end-diastolic intravascular ultrasound images with biplane coronary angiograms. Coronary flow was measured. Computational fluid dynamics was used to calculate local ESS. Complete data acquisition was then repeated. Analysis was performed on each data set in a blinded manner. The intertest correlation coefficients for all arteries for the two measurements of lumen radius, EEM radius, plaque thickness, and ESS were r = 0.96, 0.96, 0.94, 0.91, respectively (all P values < 0.0001). The 3D anatomy and ESS of human coronary arteries can be reproducibly estimated in vivo. This methodology provides a tool to examine the effect of ESS on atherogenesis, remodeling, and restenosis; the contribution of arterial remodeling and plaque growth to changes in the lumen; and the impact of new therapies. Catheter Cardiovasc Interv 2003;60:67,78. © 2003 Wiley,Liss, Inc. [source] DETECTION OF PERIVASCULAR BLOOD FLOW IN VIVO BY CONTRAST-ENHANCED INTRACORONARY ULTRASONOGRAPHY AND IMAGE ANALYSIS: AN ANIMAL STUDYCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 12 2007Manolis Vavuranakis SUMMARY 1Acute coronary syndromes are mostly the result of coronary plaque rupture. Diagnostic techniques focusing on the early detection of those plaques that are prone to rupture are still limited. Increased neovascularization in the adventitia and within the atherosclerotic plaque have recently been identified as common features of inflammation and plaque vulnerability. Contrast-enhanced intravascular imaging with microbubbles can be used to trace perfusion. 2In the present study, we examined the perivascular network of the left anterior descending coronary arteries and left circumflex arteries of four domestic, clinically healthy pigs using intracoronary ultrasound after injection of microbubbles with a differential imaging technique (ACESÔ; Computational Biomedicine Laboratory, University of Houston, Houston, TX, USA). Our aim was to detect blood flow into the coronary lumen and perivascular flow in contrast-enhanced images. Eleven regions of interest (ROI), including perivascular structures, were compared with regard to their grey scale level before and after the injection of SonoVue® (0.06 mL/kg; Bracco Diagnostics, Princeton, NJ, USA). 3A statistically significant (P = 0.018) enhancement was found in the echogenicity of the total perivascular space (adventitial region and perivascular vessels), as indicated by an increase in grey level intensity from 8.33 ± 0.80 (before) to 10.11 ± 0.88 (after microbubble injection). A significant enhancement of the 11 selected ROI (perivascular structures) was also recorded after the injection of microbubbles (from 7.92 ± 2.14 to 14.03 ± 2.44; P = 0.008). 4We believe that the detection of perivascular structures with contrast-enhanced intracoronary ultrasonography combined with proper image processing may reinforce our future efforts in the detection of vasa vasorum, an active participant in the creation of acute coronary events. [source] Cardiac computed tomography: Diagnostic utility and integration in clinical practiceCLINICAL CARDIOLOGY, Issue S1 2006Matthew J. Budoff M.D. Abstract Cardiac applications of computed tomography (CT) is a rapidly growing diagnostic area because of the ability to visualize plaque burden (coronary artery calcification [CAC]) and luminal obstruction (computed tomographic angiography [CTA]) noninvasively. Coronary artery calcification has been validated in over 1,000 studies over the last 20 years, primarily with electron beam tomography. Studies demonstrate several indications that could aid physicians in the management of symptomatic and asymptomatic patients. Determining that a symptomatic patient has no CAC is associated with both a lower risk of an abnormal nuclear study and angiographic obstruction. The ability to detect subclinical atherosclerosis (CAC) with minimal radiation and no contrast makes this an attractive method for risk stratification. New studies demonstrate a 10-fold risk of cardiovascular events with increasing amounts of coronary calcification. The invasive nature, expense, and risk resulting from invasive angiography have been instrumental in encouraging the development of new diagnostic methods that allow the coronary arteries to be visualized noninvasively. Multislice CT, with its advanced spatial and temporal resolution, has opened up new possibilities in the imaging of the heart and major vessels of the chest, including the coronary arteries. The last decade has seen great strides in the field of cardiac imaging, particularly in the ability to visualize the coronary lumen with sufficient diagnostic accuracy. Possessing that qualification, CTA is now being used increasingly in clinical practice. As a result of having high spatial and improved temporal resolutions, this imaging modality not only allows branches of the coronary artery to be evaluated, but also allows simultaneous analysis of other cardiac structures, making it extremely useful for other cardiac applications. This paper reviews the diagnostic utility and limitations of cardiac CT and how it could be integrated into clinical practice. [source] | ||||||||||