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Diameter Stenosis (diameter + stenosis)
Selected AbstractsVasodilator Stress Induces Infrequent Wall Thickening Abnormalities Compared to Perfusion Defects in Mild-to-Moderate Coronary Artery Disease: Implications for the Choice of Imaging Modality with Vasodilator StressECHOCARDIOGRAPHY, Issue 4 2004M.R.C.P., Ph.D., Prem Soman M.D. Background: Experimental evidence suggests that although vasodilator stress agents consistently induce regional flow disparity between stenosed and normal coronary vascular beds, the occurrence of functional myocardial ischemia is infrequent, especially in mild-to-moderate coronary artery stenosis. Thus, it is hypothesized that dipyridamole infusion, even at high doses, will result in a disproportionately higher frequency of perfusion defects compared to regional wall thickening abnormalities. Methods: We performed simultaneous high-dose (0.84 mg/kg) dipyridamole stress echocardiography (Echo) and Tc-99m sestamibi SPECT (MIBI, methoxyisobutyl isonitrile) in 46 patients with coronary artery diameter stenosis >50% and ,90% in one or two epicardial coronary arteries, and no previous myocardial infarction. Results: Of a total of 828 segments, MIBI showed 97 reversible defects while Echo showed only 23 reversible wall thickening abnormalities. Of the 97 segments with reversible MIBI defects, only 13 (13%) showed simultaneous reversible wall thickening abnormalities during dipyridamole infusion. There were 24 patients with MIBI defects, of whom 10 (41%) showed a corresponding wall thickening abnormality. The sensitivity of MIBI and Echo for the detection of coronary artery disease was 52% and 21%, respectively (P = 0.001). Conclusion: This suggests that vasodilator stress is not optimally suited for use with techniques that use regional wall thickening abnormality as a marker of ischemia for the diagnosis of coronary artery disease. (ECHOCARDIOGRAPHY, Volume 21, May 2004) [source] High-density lipoprotein cholesterol, C-reactive protein, and prevalence and severity of coronary artery disease in 5641 consecutive patients undergoing coronary angiographyEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 6 2008H. F. Alber ABSTRACT Background, Although high-density lipoprotein cholesterol (HDL-C) and C-reactive protein (CRP) are well-established predictors for future cardiovascular events, little information is available regarding their correlation with the prevalence and severity of angiographically evaluated coronary artery disease (CAD). Material and methods,, Five thousand six hundred forty-one consecutive patients undergoing coronary angiography for the evaluation of CAD were analysed. Cardiovascular risk factors were assessed by routine blood chemistry and questionnaire. CAD severity was graded by visual estimation of lumen diameter stenosis with significant stenoses defined as lumen diameter reduction of , 70%. Coronary angiograms were graded as one-, two- or three-vessel disease, as nonsignificant CAD (lumen irregularities < 70%) or non-CAD. Results,, HDL-C (60·3 ± 18·5 vs. 51·9 ± 15·3 mg dL,1; P < 0·001) was higher and CRP was lower (0·65 ± 1·68 vs. 1·02 ± 2·38 mg dL,1; P < 0·001) in non-CAD (n = 1517) compared to overall CAD patients (n = 4124). CAD patients were older (65·2 ± 10·5 years vs. 59·9 ± 11·4 years), more often diabetics (19·2% vs. 10·6%) and hypertensives (79·2% vs. 66·0%) and included more smokers (18·8% vs. 16·5%) (all P < 0·005). Low-density lipoprotein cholesterol (124·5 ± 38·3 vs. 126·0 ± 36·3 mg dL,1; P = NS) was similar in overall CAD and non-CAD patients with more statin users (43·4% vs. 27·9%; P < 0·001) among CAD patients. Comparing non-CAD with different CAD severities using analysis of variance, results did not change substantially. In a multivariate analysis, HDL-C and CRP remained independently associated with the prevalence of CAD. In addition, HDL-C is also a potent predictor for the severity of CAD. Conclusions,, In this large consecutive patient cohort, HDL-C and CRP are independently associated with the prevalence of CAD. In this analysis, HDL-C is an even stronger predictor for CAD than some other major classical risk factors. [source] Protected Carotid Stenting in High-Risk Patients: Results of the SpideRX Arm of the Carotid Revascularization with ev3 Arterial Technology Evolution TrialJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 5 2010ROBERT D. SAFIAN M.D. Purpose:,A prospective nonrandomized multicenter registry of 160 patients with severe carotid stenosis and high-risk features for carotid endarterectomy was conducted during the 3-month period from March to May 2005. Methods:,Carotid artery stenting (CAS) was performed with the SpideRXÔ Embolic Protection System (ev3, Inc., Plymouth, MN, USA) as part of an investigational device exemption from the Food and Drug Administration. Results:,The primary end-point of major adverse cardiac and cerebrovascular events at 30 days after CAS was observed in nine patients (5.6%), including death in four patients (2.5%), nonfatal stroke in five patients (3.1%), and nonfatal myocardial infarction in one patient (0.6%). A secondary end-point of technical success (defined as successful deployment of all devices, filter retrieval, and final diameter stenosis <50%) was achieved in 156 of 160 patients (97.5%). The only independent predictor of death or stroke at 30 days was baseline stenosis severity (P < 0.05). Conclusion:,CAS with distal embolic protection using the SpideRXÔ Embolic Protection System is a reasonable alternative for revascularization of some high-risk patients with severe carotid stenosis. (J Interven Cardiol 2010;23:491,498) [source] Cutting Balloon for In-Stent Restenosis:JOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 4 2004Acute, Long-Term Results Introduction: Conventional percutaneous coronary intervention for the treatment of in-stent restenosis (ISR) has shown a high rate of ISR (30,55%). Considering the need for both extrusion of hyperplastic intima and additional stent expansion, a cutting balloon might be more effective for the treatment of ISR. Methods: We prospectively assessed the immediate and 8-month outcome of balloon angioplasty using the Barath Cutting Balloon in 100 consecutive patients (mean age: 60.5 ± 10.8 years, 71% male). Results: In 73 lesions (73%), a good result was reached with the cutting balloon only. In 21 lesions (21%) postdilatation and in 6 lesions (6%) predilatation with a conventional balloon was necessary. The mean inflation pressure was 8.7 ± 2.0 (range: 6.0,18.0) atm. Before the procedure the mean minimal luminal diameter (MLD) was 0.95 ± 0.45 mm. Quantitative coronary analysis showed a mean diameter stenosis of 65%± 16%. Immediately after the procedure the mean MLD was 2.42 ± 0.54 mm with a mean diameter stenosis of 19%± 13%. Two patients died during the follow-up period (1 stroke, 1 nonvascular). At 8-month follow-up 26 patients (26%) reported to have anginal complaints CCS class II,IV of whom 16 (16%) needed target lesion revascularization. Conclusion: Treatment of ISR using the Barath Cutting Balloon can be performed safely with good immediate results and a relatively low need for repeated target lesion revascularization at 8-month follow-up. [source] Clinical and Angiographic Outcome after Cutting Balloon AngioplastyJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 1 2003JOHANN AUER M.D. The cutting balloon is a new device for coronary angioplasty, that, by the combination of incision and dilatation of the plaque, is believed to be promising for treatment of in-stent restenosis. The purpose of the study was to evaluate the safety and efficacy of CBA. We reviewed the immediate and 6-month follow-up angiographic and clinical outcome of 147 patients (109 men and 38 women) with a mean age of67.3 ± 10undergoing this procedure at eight interventional centers in Austria. The target lesions treated with CBA were in-stent restenosis in 61% of patients, stenosis after balloon angioplasty in 8% of patients, and native lesions in 33% of patients. Sixty-five percent of the patients included had multivessel disease. Lesion type was A in 18% of patients, B1 in 31% of patients, B2 in 39% of patients, and C in 12% of patients. The degree of stenosis was87%± 9%,the length of the target lesion treated with CBA was8.8 ± 5.1 mm. Target vessel was left circumflex artery in 22 cases, right coronary artery in 36 cases, and left anterior descending artery in 89 cases. The overall procedural success rate was 90.5%. "Stand-alone" CBA was performed in 63% of patients, the procedure was combined with coronary stenting in 16% of patients, and with balloon angioplasty in 21% of patients. Coronary complications occurred in eight cases (5.4%) with coronary dissection in seven (total dissection rate of 4.7%) and urgent bypass surgery in one case (0.7%). No further complications such as death, occlusion, or perforation of coronary arteries, embolization, or thrombosis were observed. Six-month clinical follow-up revealed q-wave myocardial infarction in 2.7% of patients, aortocoronary bypass surgery in 8.5% of patients, and repeated percutaneous coronary intervention in 17% of patients (11.5% with stenting). Six-month angiographic follow-up of patients with recurrent angina showed target lesion restenosis (>50% diameter stenosis) in 14% of patients, late lumen loss with ,50% diameter stenosis in 6% of patients and progression of "other than target" lesions with >50% diameter stenosis in 14% of patients. This series demonstrates the safety and feasibility of cutting balloon angioplasty in patients with complex coronary artery disease and in-stent restenosis. (J Interven Cardiol 2003;16:15,21) [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] High-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] Usefulness of translesional pressure gradient and pharmacological provocation for the assessment of intermediate renal artery diseaseCATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 3 2006Noah J. Jones MD Abstract Objective: We sought to determine the hemodynamic significance of intermediate RAS by measuring translesional systolic pressure gradients (TSPG), using a pressure-sensing guidewire at baseline and after acetylcholine (ACh) induced hyperemia, following selective renal artery angiography. Background: Renal artery stenosis (RAS) is a cause of reversible hypertension and nephropathy. Stenting effectively relieves RAS, however improvement in blood pressure control or renal function is variable and unpredictable. Hemodynamic significance is usually present with RAS when diameter stenosis is >75%, but is less predictable in intermediate (30%,75%) RAS. Methods: Twenty-two patients (26 renal arteries) with uncontrolled hypertension underwent invasive hemodynamic assessment because of intermediate RAS, defined as radiocontrast angiographic diameter stenosis (DS) between 30% and 75% (quantitative DS was measured prospectively). Translesional pressure gradients were measured using a 0.014" pressure-sensing wire. Hyperemia was induced by administration of intrarenal ACh. Results: Visual and measured angiographic lesion severity did not correlate with TSPG either at baseline (visual DS, R2 = 0.091, P = 0.13; measured DS, R2 = 0.124, P = 0.07) or with hyperemia (visual DS, R2 = 0.057, P = 0.24; measured DS, R2 = 0.101, P = 0.12). Baseline and maximal hyperemic gradient did correlate (R2 = 0.567; P < 0.05). Pharmacological provocation produced a significant increase in TSPG (mean; baseline, 18 ± 21 vs. hyperemia, 34 ± 41 mm Hg; P < 0.05). A hemodynamically significant lesion (TSPG > 20 mm Hg) was found in 14/26 (54%) arteries (13 patients); 13 (60%) patients subsequently underwent renal artery stenting for hemodynamically significant RAS. At follow-up (at least 30 days), there was a significant decrease in systolic blood pressure (mean; 167 ± 24 vs. 134 ± 19 mm Hg; P < 0.001). Conclusions: Intrarenal administration of ACh induces hyperemia and can be used to unmask resistive renal artery lesions. Gradient measurement and induced hyperemia may be warranted in the invasive assessment of intermediate renal artery stenoses, rather than relying on stenosis severity alone. Further study is needed to determine whether translesional pressure gradients and pharmacological provocation predict clinical benefit after renal artery stenting. © 2006 Wiley-Liss, Inc. [source] Quantitative coronary arteriography on digital flat-panel systemCATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 2 2004Paul L. Van Herck MD Abstract On images acquired with a digital flat-panel (DFP) detector, known for its better image quality, the performance of a validated quantitative coronary arteriography (QCA) software, CAASII (Cardiovascular Angiography Analysis System or CAAS), and a DFP-dedicated QCA algorithm (flat-panel analysis software or FPAS) was compared in a phantom and a patient study. On phantom, FPAS performed with higher accuracy the quantification of the smallest tubes and the calibration of an empty catheter. The overall accuracy and precision for the quantification procedure was better for FPAS (0.07 ± 0.04 mm) than for the CAAS (0.19 ± 0.06 mm; P = 0.03 and P < 0.01, respectively). In the patient study, the main difference between the two algorithms was found in the small diameters: CAAS almost always gave higher values than FPAS for the minimal luminal diameter (P < 0.001) and could only give values up to 70% for diameter stenosis. In conclusion, the FPAS can be considered more appropriate for assessing severe stenoses on digital flat-panel images. Catheter Cardiovasc Interv 2004;63:192,200. © 2004 Wiley-Liss, Inc. [source] Gold coating and restenosis after primary stenting of ostial renal artery stenosisCATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 1 2003Thomas Zeller MD Abstract Predictors of restenosis after stent angioplasty of ostial renal artery stenosis (RAS) and long-term technical success, particularly the influence of gold coating, are unknown. During a 4-year period (1996,2000), we treated 156 consecutive patients with 219 ostial RAS of , 70% diameter stenosis. Gold-coated stents were used in 29% of RAS (n = 64); the vessel diameter ranged from 3 to 9 mm. The restenosis rate was 11.4% at 12 months, 12.2% for gold-coated stents and 11.1% for noncoated stents. Restenosis rates were 16% for , 4 mm, 17% for 5 mm, 10% for 6 mm, and 0% for , 7 mm (P , 0.05). In a backward stepwise logistic regression analysis including gold coating, vessel diameter, gender, diabetes, smoking status, as well as lesion diameter stenosis before and after stenting, vessel diameter was found the only independent predictor of restenosis (odds ratio = 0.57; 95% CI = 0.35,0.93; P = 0.02, for an increase in vessel diameter of 1 mm). Gold coating was not a significant predictor (odds ratio = 1.09; 95% CI = 0.39,3.03; P = 0.87). Seven major (4.5%) complications occurred. There were no procedural fatalities. The restenosis rate after stent angioplasty of ostial RAS is influenced by the vessel diameter but not by gold coating. Catheter Cardiovasc Interv 2003;60:1,6. © 2003 Wiley,Liss, Inc. [source] | ||||||||||