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Intravascular Ultrasound (intravascular + ultrasound)
Terms modified by Intravascular Ultrasound Selected AbstractsIntravascular Ultrasound to Assess Extracranial Vertebral Artery Restenosis: Case ReportJOURNAL OF NEUROIMAGING, Issue 3 2008Rishi Gupta MD ABSTRACT We present a case report of a patient who developed restenosis 5 months after initial stent placement. computed tomography (CT) angiography revealed a 70% stenosis, while conventional angiography revealed a 40% stenosis. An intravascular ultrasound (IVUS) was used to assess the degree of narrowing along with the mechanism causing the stenosis. IVUS can be utilized to resolve discrepancies between imaging modalities for degree of stenosis and also aid in determining the mechanism of restenosis after stent placement in the extracranial vertebral arteries. [source] Intravascular ultrasound imaging of the pulmonary arteries in primary pulmonary hypertensionRESPIROLOGY, Issue 1 2000Takaaki Nakamoto Objective: Intravascular ultrasound has the unique ability to provide cross-sectional images of the arterial wall. This study examined intravascular ultrasound (IVUS) images of the proximal pulmonary arteries in primary pulmonary hypertension (PPH). Methodology: Study 1: Specimens from four patients who had died of PPH (in vitro PPH group) were compared with those of three patients who had died of subarachnoid haemorrhage but had no evidence of cardiopulmonary disease (in vitro control group). Three-centimetre segments of the following levels were examined by IVUS: pulmonary trunk, eight secondary branch arteries of the upper, middle, and lower lobes of both lungs, and the thoracic descending aorta. Study 2: Four patients with PPH (in vivo PPH group) and five patients without pulmonary hypertension and no evidence of cardiopulmonary disease (in vivo control group) were examined. The IVUS images of the apical segmental artery of the right upper lobe and the descending branch of the right pulmonary artery were studied. Results: Echographic examination of formalin-fixed preparations of secondary branch sections of the pulmonary artery failed to show a clear three-layer structure in the in vitro control group (24 preparations), but a distinct three-layer structure and increased vessel wall thickness were observed in the in vitro PPH group (32 preparations). Similar findings were obtained in the in vivo study. The mean echo density of the proximal pulmonary arterial wall correlated well with the mean pulmonary arterial pressure (mPA) in the in vitro PPH, and also correlated with the mPA in the in vivo study (r = 0.960, P < 0.0001). The echo intensity of secondary branch sections of the pulmonary artery was higher in the in vitro PPH group than in the in vitro control group (180.5 ± 27.0 vs 132.5 ± 26.7 counts, P < 0.001); similar results were obtained in the in vivo study (144.7 ± 23.4 vs 85.0 ± 14.3 counts, P < 0.01). Conclusions: These results suggest that the histological changes detected in the pulmonary artery walls in the PPH group were responsible for the increased echo intensity. [source] Impact of intravascular ultrasound for the treatment of calcified infrarenal aortic stenosis: A case report study,CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 6 2008Masahiko Hara MD Abstract We report two cases of heavily calcified infrarenal aortic stenosis that were successfully treated by Intravascular ultrasound- (IVUS)-guided stenting. Two middle-aged women visited our hospital due to intermittent claudication. Diagnostic arteriography revealed possible infrarenal aortic stenosis even though the findings were equivocal. IVUS demonstrated heavily calcified atherosclerotic lesions and allowed the accurate assessment of the types and extents of the lesions to be treated in both cases. The patients successfully underwent stent implantation according to the findings of IVUS. IVUS significantly contributed to the interventional successes. © 2008 Wiley-Liss, Inc. [source] The importance of gender on coronary artery size: In-vivo assessment by intravascular ultrasoundCLINICAL CARDIOLOGY, Issue 5 2004Sang-Gon Kim M.D. Abstract Background: It remains controversial whether women have smaller coronary arteries than men because of a gender-specific trait, or whether the observed differences are primarily due to a difference in body size. Intravascular ultrasound (IVUS), with its ability to provide unique coronary images that allow precise measurement of arterial size in vivo, is ideally suited to address this issue. Hypothesis: Female gender, independent of body size, is associated with smaller coronary artery size as measured by intracoronary ultrasound. Methods: Intravascular ultrasound images of normal left main arteries were identified retrospectively from a single center database. Associations between demographic and clinical characteristics (including body size) and left main coronary dimensions were assessed with univariant and multivariate regression analyses. Results: We identified 257 completely normal left main arteries. Mean left main arterial areas were smaller in women than in men (17.2 vs. 20.6 mm2, p < 0.001), as were mean luminal areas (14.0 vs. 16.7 mm2, p < 0.001). By multiple regression analysis, the independent predictors of left main lumen were body surface area (p < 0.001) and gender (p = 0.003). Conclusions: Body surface area and gender are both independent predictors of coronary artery size, although body size has a greater influence than gender. [source] Clinical methods for the evaluation of endothelial function , a focus on resistance arteriesFUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 3 2006Robinson Joannides Abstract Endothelial dysfunction is a key event in the pathophysiology of cardiovascular diseases and appears as a strong independent predictor of cardiovascular events. In this context, biological evaluation of endothelial circulating markers can be helpful. However, functional tests using pharmacological stimuli appear more specific for the study of resistance arteries. These methods consist in the evaluation of the endothelium-dependent changes in regional vascular flow in response to local infusion of substances that act through endothelial receptors without modification of systemic arterial pressure and in comparison with a non endothelium-dependent relaxation. Flow is measured by Doppler and intravascular ultrasound in coronary circulation, laser Doppler in skin and by venous occlusion plethysmography in peripheral muscular arteries. Similar studies can be performed ex vivo using isolated resistance arteries obtained from fat subcutaneous biopsies. In addition, other information can be obtained from reactive hyperemia and the study of the flow-mediated dilatation of conduit arteries to enable a selective and comprehensive approach of the heterogeneity of endothelial function in pathophysiology. [source] An Enhanced Device for Transluminal Retrieval of Vascular Stents Without Surgical Procedures: Experimental StudiesJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 3 2010MASAYUKI TSUCHIDA M.D. Background: Although efforts have been focused on developing endovascular procedures by which intravascular devices such as stents could be effectively deployed, few data exist regarding devices for the nonsurgical retrieval of deployed stents. Therefore, we designed to enable retrieval of deployed stents without a surgical procedure. Methods: The device consisted of four components: ultra-low profile forceps with 2.0 mm in diameter, conducting shaft with 1.8 mm in diameter, control handle by which the forceps is opened or closed, and a covering sheath. This device was designed to advance into the vessel lumen along a 0.014-inch guidewire by over the wire fashion. Results: The forceps could firmly catch nonexpanded as well as expanded tubular-type stents with open cells in an in vitro model that was 4.0 mm in diameter. Then, we used this device in porcine renal arteries with 2.5,5.0 mm in diameter. At first, a fragmented 0.014-inch guidewire could be safely removed without vessel damage that was confirmed by intravascular ultrasound. This device could successfully remove four of five inappropriately and 11 of 14 appropriately deployed stents. Under these conditions, intravascular ultrasound demonstrated minor vessel wall dissection in two-third of cases. Conclusions: These results demonstrate that the present device can be used for transluminal removal of foreign bodies such as nonexpanded as well as expanded stents in acute phase. Further miniaturization may enable using this type of device in the renal as well as coronary arteries. (J Interven Cardiol 2010;23:264,270) [source] Mechanisms of Late Stent Malapposition After Primary Stenting in ST-Elevation Myocardial Infarction: A Subanalysis of the Selection TrialJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 3 2009TANIA CHECHI M.D. Background: One of the major predictors of late stent malapposition (LSM) is primary stenting in acute myocardial infarction. However, mechanisms of LSM are still under debate. Methods: Patients with ST-elevation myocardial infarction (STEMI) and enrolled in the SELECTION trial (38 patients in the paclitaxel-eluting stent, PES, and 35 in the bare metal stent, BMS, cohort) were retrospectively analyzed to evaluate LSM, by means of intravascular ultrasound (IVUS) data recorded at the index and 7-month follow-up procedures. Results: Stent malapposition was documented in 21 lesions in 21 patients (28.8%): in 8 of these 21 patients (38.1%) it was LSM. Although statistical significance was not reached, LSM was more frequent after PES than BMS implantation (15.8% vs. 5.7%). LSM was mainly located within the body of the stent (62.5% of the cases). At the LSM segment, a significant increase of vessel area (19.2 ± 3.3 mm2 vs. 21.9 ± 5.3 mm2, P = 0.04) and a reduction of plaque area (12.6 ± 4.6 mm2 vs. 9.1 ± 3.9 mm2, P = 0.04) were observed at IVUS between the index and follow-up procedure. Conclusions: After primary stenting for STEMI, LSM seems to be more frequent after PES rather than BMS implantation. In the STEMI setting, possible mechanisms leading to LSM include positive remodeling and plaque mass decrease. [source] Efficacy and Safety of Absorbable Metallic Stents with Adjunct Intracoronary Beta Radiation in Porcine Coronary ArteriesJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 5 2007F.A.C.C., RON WAKSMAN M.D. Background: Absorbable metallic stents (AMS) utilizing Mg alloy carry advantages over permanent metallic stents because of their potential to eliminate stent thrombosis, chronic inflammation, or artifacts with noninvasive imaging. These stents, however, are associated with a modest degree of late recoil and intimal hyperplasia. The aim of the study was to test whether adjunct vascular brachytherapy (VBT) compared to AMS alone can overcome these limitations. Methods: Juvenile domestic pig coronary arteries underwent implantation of either AMS (n = 11) with prior adjunct VBT utilizing Sr/Y-90 , source seeds, with a dose of 24 Gy at 2 mm from the source, or AMS alone (n = 11). At 28 days following intravascular ultrasound, vessels were harvested and analyzed by histomorphometry. Results: Intravascular ultrasound analysis indicated that at follow-up, though statistically not significant, lumen and stent areas in the segments deployed with AMS following radiation were larger than those deployed with AMS alone (3.94 ± 1.38 and 3.53 ± 1.75 vs. 2.99 ± 1.05 and 3.58 ± 1.48). Extrastent plaque and intrastent plaque areas in the same segments were smaller (2.76 ± 0.82 and 0.24 ± 0.47 vs. 3.25 ± 1.94 and 0.58 ± 0.81). Morphometric data indicate that vessels in the VBT + AMS group showed characteristics of delayed healing and re-endothelialization. Neointimal area was significantly lower in the VBT + AMS group (0.49 ± 0.34) compared to AMS (1.3 ± 0.62, P = 0.001). Lumen area of the VBT + AMS was larger when compared with AMS alone (2.49 ± 0.82 vs. 1.75 ± 0.51, P = 0.02). Conclusion: VBT as an adjunct to AMS further reduces the intimal hyperplasia and improves the lumen area when compared to AMS alone but does not have any impact on late recoil. [source] Increased Dosage during Intracoronary Irradiation Due to Overlapped Source Stepping Shows No Long-Term Adverse Changes in Vessel MorphologyJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 3 2004BONNI SYEDA M.Sc., M.D. Purpose: The purpose of this analysis was to evaluate if overdosage during intracoronary irradiation due to overlapped source stepping may result in long-term morphologic changes in vessel anatomy. Methods: Baseline angiograms of patients with in-stent restenosis undergoing coronary reintervention followed by intracoronary irradiation with source stepping were analyzed. Overlapping was considered present for the segment with overlapped reference isodose length (RIL) (RIL = segment with ,90% of reference dose at 1 mm vessel wall depth). Baseline and 6-months follow-up volumetric intravascular ultrasound (IVUS) analysis were performed for the overlapped segment and for proximal and distal segments of equal length. Results: Overlapping was found in six patients (three patients: 32P treatment; three patients: 90Sr/Y treatment); final analysis was performed in four patients. Comparison of the baseline and follow-up IVUS volumetric parameters revealed no significant change in lumen or vessel volumes at segments of overlaps in comparison to proximal and distal reference segments. Conclusion: Increased dosage due to overlapping during source stepping is not associated with morphologic changes in vessel anatomy at follow-up. (J Interven Cardiol 2004;17:143,149) [source] Vulnerable Plaque: The Pathology of Unstable Coronary LesionsJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 6 2002RENU VIRMANI M.D. Vulnerable plagues have been defined as precursors to lesions that rupture. However, coronary thrombosis may occur from other lesions like plaque erosion and calcified nodules, although to a lesser frequency than rupture. Therefore, the definition of vulnerable plaque should be all-inclusive. Using descriptive terminology, the authors define the precursor lesion of plaque rupture as "thin-cap fibroatheroma" (TCFA). Morphologically, TCFAs have a necrotic core with an overlying thin fibrous cap (< 65 mm) consisting of collagen type I, which is infiltrated by macrophages. These lesions are most frequent in the coronary tree of patients dying with acme myocardial infarction and least common in those with plaque erosion. TCFAs are more common in patients with high serum total cholesterol (TC) and a high TC to high density cholesterol ratio, in women >50 years, and in those patients with elevated levels of high sensitivity C-reactive protein. TCFAs are mostly found in the proximal left anterior descending coronary arteries and less commonly in the proximal right or the proximal left circumflex coronary arteries. In TCFAs, necrotic core length is , 2,17 mm (mean 8 mm) and the underlying cross-sectional luminal narrowing in over 75% of cases is < 75% (< 50% diameter stenosis). The area of the necrotic core in at least 75% of cases is ,3 mm2. Clinical studies of TCFAs are limited as angiography and intravascular ultrasound (TVUS) catheters cannot precisely identify these lesions. Newer catheters and other techniques are at various stages of development and will play a significant role in the understanding of plaque progression and the development of symptomatic coronary artery disease. [source] Intravascular Ultrasound to Assess Extracranial Vertebral Artery Restenosis: Case ReportJOURNAL OF NEUROIMAGING, Issue 3 2008Rishi Gupta MD ABSTRACT We present a case report of a patient who developed restenosis 5 months after initial stent placement. computed tomography (CT) angiography revealed a 70% stenosis, while conventional angiography revealed a 40% stenosis. An intravascular ultrasound (IVUS) was used to assess the degree of narrowing along with the mechanism causing the stenosis. IVUS can be utilized to resolve discrepancies between imaging modalities for degree of stenosis and also aid in determining the mechanism of restenosis after stent placement in the extracranial vertebral arteries. [source] Echogenic liposome compositions for increased retention of ultrasound reflectivity at physiologic temperatureJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 6 2008Kyle D. Buchanan Abstract Targetable echogenic liposomes (ELIP) for ultrasound enhancement of atheroma have recently been developed; however, their retention of echogenicity at physiological temperature is less than desirable. The purpose of this study was to improve ELIP stability and increase clinical potential. The approach utilized the original procedures but involved manipulation of the lipid composition by reducing the level of unsaturation of the phospholipids components to minimize the rate of loss of echogenicity. Echogenicity was measured using a 20 MHz intravascular ultrasound (IVUS) catheter and quantified (as mean gray scale values) using computer-assisted videodensitometry. The optimal preparation for retention of echogenicity stability at physiologic temperature was egg phosphatidylcholine/dipalmitoylphosphatidylcholine/dipalmitoylphos-phatidylethanolamine/dipalmitoylphosphatidylglycerol/cholesterol (27:42:8:8:15, molar percent). This preparation retained 51,±,3.5% of its echogenicity after 1 h at 37°C, more than 5× that retained by the previously descried preparation. In this composition nearly 2/3 of the phosphosphatidylcholine is fully saturated. Such an increase in saturation is anticipated to stiffen the lipid acyl chains. The air pockets that are responsible for reflection of ultrasound waves can be assumed to be stabilized by a lipid monolayer at the interface between the air and bulk water. The increased rigidity of that monolayer is presumed to be responsible for reducing the loss of air and extending the duration of echogenic activity. The stability of this improved formulation now appears to be more than adequate for clinical applications. © 2007 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 97:2241,2248, 2008 [source] Intravascular ultrasound imaging of the pulmonary arteries in primary pulmonary hypertensionRESPIROLOGY, Issue 1 2000Takaaki Nakamoto Objective: Intravascular ultrasound has the unique ability to provide cross-sectional images of the arterial wall. This study examined intravascular ultrasound (IVUS) images of the proximal pulmonary arteries in primary pulmonary hypertension (PPH). Methodology: Study 1: Specimens from four patients who had died of PPH (in vitro PPH group) were compared with those of three patients who had died of subarachnoid haemorrhage but had no evidence of cardiopulmonary disease (in vitro control group). Three-centimetre segments of the following levels were examined by IVUS: pulmonary trunk, eight secondary branch arteries of the upper, middle, and lower lobes of both lungs, and the thoracic descending aorta. Study 2: Four patients with PPH (in vivo PPH group) and five patients without pulmonary hypertension and no evidence of cardiopulmonary disease (in vivo control group) were examined. The IVUS images of the apical segmental artery of the right upper lobe and the descending branch of the right pulmonary artery were studied. Results: Echographic examination of formalin-fixed preparations of secondary branch sections of the pulmonary artery failed to show a clear three-layer structure in the in vitro control group (24 preparations), but a distinct three-layer structure and increased vessel wall thickness were observed in the in vitro PPH group (32 preparations). Similar findings were obtained in the in vivo study. The mean echo density of the proximal pulmonary arterial wall correlated well with the mean pulmonary arterial pressure (mPA) in the in vitro PPH, and also correlated with the mPA in the in vivo study (r = 0.960, P < 0.0001). The echo intensity of secondary branch sections of the pulmonary artery was higher in the in vitro PPH group than in the in vitro control group (180.5 ± 27.0 vs 132.5 ± 26.7 counts, P < 0.001); similar results were obtained in the in vivo study (144.7 ± 23.4 vs 85.0 ± 14.3 counts, P < 0.01). Conclusions: These results suggest that the histological changes detected in the pulmonary artery walls in the PPH group were responsible for the increased echo intensity. [source] Coronary Flow Reserve by Transthoracic Echocardiography Predicts Epicardial Intimal Thickening in Cardiac Allograft VasculopathyAMERICAN JOURNAL OF TRANSPLANTATION, Issue 7 2010F. Tona Cardiac allograft vasculopathy (CAV) is the leading cause of morbidity and mortality in heart transplantation (HT). We sought to investigate the role of coronary flow reserve (CFR) by contrast-enhanced transthoracic echocardiography (CE-TTE) in CAV diagnosis. CAV was defined as maximal intimal thickness (MIT) assessed by intravascular ultrasound (IVUS) ,0.5 mm. CFR was assessed in the left anterior descending coronary artery in 22 HT recipients at 6 ± 4 years post-HT. CAV was diagnosed in 10 patients (group A), 12 had normal coronaries (group B). The mean MIT was 0.7 ± 0.1 mm (range 0.03,1.8). MIT was higher in group A (1.16 ± 0.3 mm vs. 0.34 ± 0.07 mm, p < 0.0001). CFR was 3.1 ± 0.8 in all patients and lower in group A (2.5 ± 0.6 vs. 3.7 ± 0.3, p < 0.0001). CFR was inversely related with MIT (r =,0.774, p < 0.0001). A cut point of ,2.9, identified as optimal by receiver operating characteristics analysis was 100% specific and 80% sensitive (PPV = 100%, NPV = 89%, Accuracy = 91%). CFR assessment by CE-TTE is a novel noninvasive diagnostic tool in the detection of CAV defined as MIT ,0.5 mm. CFR by CE-TTE may reduce the need for routine IVUS in HT. [source] Systemic Markers of Inflammation Are Associated with Cardiac Allograft Vasculopathy and an Increased Intimal Inflammatory ComponentAMERICAN JOURNAL OF TRANSPLANTATION, Issue 6 2010S. Arora We evaluated an extensive profile of clinical variables and immune markers to assess the inflammatory milieu associated with cardiac allograft vasculopathy (CAV) assessed by intravascular ultrasound (IVUS) and virtual histology (VH). In total, 101 heart transplant (HTx) recipients were included and underwent IVUS/VH examination and measurement of plasma C-reactive protein (CRP), soluble tumor necrosis factor receptor-1, interleukin-6, osteoprotegerin, soluble gp130, von Willebrand factor, vascular cell adhesion molecule-1 (VCAM-1) and neopterin. Mean Maximal Intimal Thickness (MIT) was 0.61 ± 0.19 mm and mean fibrotic, fibrofatty, dense calcified and necrotic core components were 55 ± 15, 14 ± 10, 15 ± 13 and 17 ± 9%, respectively. In multivariate analysis, CRP > 1.5 mg/L (OR 4.6, p < 0.01), VCAM-1 > 391 ng/mL (adjusted OR 3.2, p = 0.04) and neopterin > 7.7 nmol/L (OR 3.8, p = 0.02) were independently associated with MIT > 0.5 mm. Similarly, CRP > 1.5 mg/L (OR 3.7, p < 0.01) and VCAM-1 > 391 (OR 2.7, p = 0.04) were independently associated with an increased intimal inflammatory component (dense calcified/necrotic core component > 30%). Advanced CAV is associated with elevated CRP, VCAM-1 and neopterin and the two former biomarkers are also associated with an increased intimal inflammatory component. Forthcoming studies should clarify if routine measurements of these markers can accurately identify HTx recipients at risk of developing advanced CAV and vulnerable lesions. [source] Treatment by Mycophenolate Mofetil of Advanced Graft Vascular Disease in Non-Human Primate Recipients of Orthotopic Aortic AllograftsAMERICAN JOURNAL OF TRANSPLANTATION, Issue 7 2003Jochen Klupp Failure to control chronic graft dysfunction [e.g. graft vascular disease (GVD)] is the primary cause of immunologic graft failure. This is the first study of mycophenolate mofetil (MMF) for the treatment of GVD in non-human primate recipients of aortic allografts. Abdominal aortic allografts were exchanged between mixed leukocyte reaction (MLR) -mismatched, blood-group-compatible cynomolgus monkeys. Six control recipients were untreated. Individualized treatment with frequent dose adjustments of MMF insured that treatment was close to the maximum tolerated dose (mean 99.2 mg/kg/day). Immune-mediated injury proceeded unhindered until day 45, after which MMF treatment began. Changes in intimal volume (IV) were quantified by intravascular ultrasound (IVUS) and compared to histology on day 105. Serial IVUS measurements of IV (mm3) in controls showed progressive GVD. In four out of six animals, MMF was well tolerated, thus enabling optimum treatment; in all these animals, IV was significantly less than in the control animals (p = 0.02). In the two remaining animals, high doses were not tolerated; at day 105, there was no significant difference in IV between them and the controls. We found a significant correlation between the mean MMF tolerated dose and the inhibition of progression of IV (r = ,0.88, p = 0.015). When high MMF doses were tolerated, MMF slowed progression of GVD. [source] Invasive assessment of the coronary circulation: intravascular ultrasound and DopplerBRITISH JOURNAL OF CLINICAL PHARMACOLOGY, Issue 6 2002David E. Newby First page of article [source] Left main coronary artery compression from pulmonary artery enlargement due to pulmonary hypertension: A contemporary review and argument for percutaneous revascularization,CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 4 2010Michael S. Lee MD Abstract Extrinsic compression of the left main coronary artery by an enlarged pulmonary artery is an increasingly recognized and potentially reversible cause of angina and left ventricular dysfunction in patients with pulmonary hypertension. The diagnosis of extrinsic left main coronary artery compression requires a high index of suspicion and should be considered in patients with severe pulmonary hypertension who experience angina. Coronary angiography with intravascular ultrasound is the gold standard for diagnosis of this condition, though cardiac computed tomography and magnetic resonance angiography allow for noninvasive means of screening. The optimal treatment is debatable, but percutaneous coronary intervention appears to be a feasible, safe, and effective treatment option for patients with extrinsic compression of the left main coronary artery from pulmonary artery enlargement. Given the high risk of postoperative right ventricular failure and mortality observed with surgical revascularization in these patients, we recommend that physicians recognize percutaneous coronary intervention as the preferred revascularization strategy for selected patients with extrinsic compression of the left main coronary artery due to pulmonary hypertension. © 2010 Wiley-Liss, Inc. [source] Histology of highly echolucent regions in optical coherence tomography images from two patients with sirolimus-eluting stent restenosis,CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 6 2010Hiroyuki Nagai MD Abstract We report on two patients with sirolimus-eluting stent (SES) restenosis lesions who showed highly echolucent regions by optical coherence tomography (OCT) and who could be assessed histologically after removal by directional coronary atherectomy (DCA). One restenosis lesion had a bilayer structure of hyperechoic outer layers and highly echolucent inner layers on OCT images and histologically exhibited myxomatous neointima tissue in the highly echolucent regions; another restenosis case showed patchy and highly echolucent regions throughout the layers and its histology revealed fibrin thrombosis. We should be aware that patterns of echolucent on OCT images may have various histology. OCT allows the visualization of fine lesions that conventional intravascular ultrasound (IVUS) cannot provide. The OCT images of drug-eluting stent restenosis lesions often show echolucent regions [Shuzoh et al., EuroInterv 2006;1:484]. However, no histological study of the lesions has been reported to date. Here we report on two patients with SES restenosis lesions that showed highly echolucent regions by OCT and that could be assessed histologically after removal by DCA. © 2009 Wiley-Liss, Inc. [source] Rupture of a peripheral popliteal artery plaque documented by intravascular ultrasound: A case report,CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 7 2009Hiroaki Kohno MD Abstract A 58-year-old male with dyslipidemia and coronary spastic angina suddenly experienced pain in the right limb while walking on November 1, 2008. Right-ankle brachial pressure index (ABI) was decreased (0.80) and left-ABI was normal (1.24). Bilateral ABI was normal during January 2008. Ultrasonography in the right-lower limb artery revealed severe stenosis in the right-popliteal artery with extended and large echolucent plaques containing an isoechoic area. We carried out lower limb angiography: subtotal occlusion of the popliteal artery was found. By intravascular ultrasound (IVUS), right-popliteal artery plaques were echolucent and eccentric; ulceration with a thin fibrous cap was noted. Percutaneous transluminal angioplasty was done and popliteal artery blood flow was improved. Right-ABI improved to 1.13 after 4 days. To prevent the progression and rupture of the plaques, lipid-lowering therapy and antiplatelet therapy were started. Plaque rupture of the popliteal artery was diagnosed by these characteristics on IVUS. Patients with peripheral artery disease may have plaque rupture similar to those with acute coronary syndromes who have identical unstable plaques and unstable atheromas. In addition to appropriate local revascularization, systemic therapy to stabilize the unstable plaque is indicated because failure to do so may cause recurrent events. © 2009 Wiley-Liss, Inc. [source] Impact of intravascular ultrasound for the treatment of calcified infrarenal aortic stenosis: A case report study,CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 6 2008Masahiko Hara MD Abstract We report two cases of heavily calcified infrarenal aortic stenosis that were successfully treated by Intravascular ultrasound- (IVUS)-guided stenting. Two middle-aged women visited our hospital due to intermittent claudication. Diagnostic arteriography revealed possible infrarenal aortic stenosis even though the findings were equivocal. IVUS demonstrated heavily calcified atherosclerotic lesions and allowed the accurate assessment of the types and extents of the lesions to be treated in both cases. The patients successfully underwent stent implantation according to the findings of IVUS. IVUS significantly contributed to the interventional successes. © 2008 Wiley-Liss, Inc. [source] Reproducible microvascular dysfunction with dobutamine infusion in Takotsubo cardiomyopathy presenting with ST segment elevationCATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 5 2006Stacy D. Brewington MD Abstract Takotsubo (ampulla) cardiomyopathy, or broken heart syndrome, is an underrecognized cardiac illness that usually presents as an acute coronary syndrome in postmenopausal females. The disorder is frequently associated with episodes of mental or physical stress, implicating an abnormal cardiac response to increased catecholamines. Although death has been reported during the index event, the long-term prognosis is good with full recovery of left ventricular function. We present a case of Takotsubo cardiomyopathy mimicking anterior ST segment elevation myocardial infarction precipitated by dobutamine stress testing. Reinfusion of dobutamine in the catheterization laboratory reproduced symptoms with angiography and intravascular ultrasound supporting the theory of abnormal microvascular circulation as the etiology of Takotsubo cardiomyopathy. Acute and delayed magnetic resonance imaging demonstrated no infarction with complete recovery of ventricular function. © 2005 Wiley-Liss, Inc. [source] "Head-to-head comparison between sirolimus-eluting and paclitaxel-eluting stents in patients with complex coronary artery disease: An intravascular ultrasound study"CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 6 2006FSCAI, Pavel, ervinka MD Abstract Background: The aim of this study was to assess neointimal hyperplasia following sirolimus-eluting (SES) and paclitaxel-eluting stents (PES) implantation in a patients with complex coronary disease. Method: Between January to December 2004, 70 patients were enrolled in this study (SES = 37; PES = 33. The primary objective was to assess the efficacy of SES and PES on neointimal proliferation inhibition in patients with complex coronary lesions by volumetric 3D intravascular ultrasound (IVUS) assessment at six-month follow-up. Results: Baseline clinical, demographic or angiographic characteristics were well balanced in both groups. All procedures as well as hospitalisation were uneventful. The percentage of B2/C lesions in our study was >90% in both groups. The IVUS-assessed in-stent mean neointimal hyperplasia volume was significantly lower in lesions treated with SES compared to PES (4.1 ± 11 mm3 vs. 17.4 ± 23 mm3, p < 0.002) at 6 month follow-up. No difference in both MACE (3.0 versus 6.0%, p = NS) and restenosis (5.4 versus 9.1%, p = NS) were found. The in-segment late loss at six month was 0.26 mm in the SES and 0.48 mm in the PES group (p = NS). Conclusions: The present study showed reduced neointimal proliferation after sirolimuseluting as compared to paclitaxel-eluting stents in patients with complex coronary artery disease. Both SES and PES were associated with low rate of angiographic restenosis or major adverse cardiovascular events. © 2006 Wiley-Liss, Inc. [source] The importance of gender on coronary artery size: In-vivo assessment by intravascular ultrasoundCLINICAL CARDIOLOGY, Issue 5 2004Sang-Gon Kim M.D. Abstract Background: It remains controversial whether women have smaller coronary arteries than men because of a gender-specific trait, or whether the observed differences are primarily due to a difference in body size. Intravascular ultrasound (IVUS), with its ability to provide unique coronary images that allow precise measurement of arterial size in vivo, is ideally suited to address this issue. Hypothesis: Female gender, independent of body size, is associated with smaller coronary artery size as measured by intracoronary ultrasound. Methods: Intravascular ultrasound images of normal left main arteries were identified retrospectively from a single center database. Associations between demographic and clinical characteristics (including body size) and left main coronary dimensions were assessed with univariant and multivariate regression analyses. Results: We identified 257 completely normal left main arteries. Mean left main arterial areas were smaller in women than in men (17.2 vs. 20.6 mm2, p < 0.001), as were mean luminal areas (14.0 vs. 16.7 mm2, p < 0.001). By multiple regression analysis, the independent predictors of left main lumen were body surface area (p < 0.001) and gender (p = 0.003). Conclusions: Body surface area and gender are both independent predictors of coronary artery size, although body size has a greater influence than gender. [source] Endothelial dysfunction, subangiographic atheroma, and unstable symptoms in patients with chest pain and normal coronary arteriogramsCLINICAL CARDIOLOGY, Issue 9 2000Jonathan R. Clague M.D. Abstract Background: Patients with chest pain and normal coronary arteriograms (CPNA) may present with unstable symptoms and other evidence of ischemia during clinical follow-up. Although repeat angiography usually proves negative, functional assessment of coronary vasomotor abnormalities may provide additional pathophysiologic information. Hypothesis: The study was undertaken to evaluate the relationship between endothelial dysfunction and subangiographic atheroma in patients with CPNA undergoing repeat angiography because of unstable symptoms. Methods: We investigated nine patients with CPNA (8 women, mean age 57 ± 9 years) undergoing repeat angiography because of unstable anginal symptoms. After normal angiography, simultaneous coronary epicardial and microvascular vasomotor responses to intracoronary vasodilators [acetylcholine (10,6 M), adenosine (18 ,g) and nitroglycerin (300 ,g)] were investigated in the left anterior descending artery using quantitative angiography and Doppler flow measurements. The presence of subangiographic atheroma was assessed by intravascular ultrasound. Results: Three patients demonstrated proximal and distal epicardial vasoconstriction and a reduction in coronary flow in response to acetylcholine, indicating concordant epicardial and microvascular endothelial dysfunction. These changes were associated with chest pain and ischemic electrocardio-graphic changes in two patients. None of the remaining patients suffered chest pain in response to intracoronary acetylcholine. Six patients had significant subangiographic disease (intimal thickness >0.3 mm) on intravascular ultrasound imaging, and multivariate analysis indicated a significant relationship (R2 = 0.89, overall p = 0.001) between the extent of subangiographic disease and both plasma cholesterol concentration and hypertensive history. No significant relationship was demonstrated between endothelial dysfunction and the extent of subangiographic disease. Conclusion: Concordant epicardial and microvascular endothelial dysfunction may be pathophysiologically and clinically significant in unstable patients with CPNA but does not appear to be directly related to the extent of subangiographic atheroma. [source] | ||||||||||||||||||||||