Intimal Thickness (intimal + thickness)

Distribution by Scientific Domains

Selected Abstracts

Systemic Markers of Inflammation Are Associated with Cardiac Allograft Vasculopathy and an Increased Intimal Inflammatory Component

S. 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]

Biodegradable External Stents Inhibit Saphenous Vein Graft Thickening in the Pig

P Gadsdon
Aim: External, non-restrictive, macro-porous stents prevent neointima formation in porcine vein grafts and have been proposed as a therapeutic approach to the prevention of late vein graft failure. Since these stents are non-biodegradable and therefore may elicit deleterious long-term, inflammatory, infective and mechanical complications the effect of external macro-porous biodegradable (polyglactin) stents on neointimal and medial thickening in porcine vein grafts was investigated. Methods: Bilateral vein saphenous vein-carotid artery interposition grafting was performed in Large White pigs (22,36 kg, n = 6) with external placement of 8 mm diameter polyglactin stents on one side, the contralateral side acting as a control. One month after surgery, graft wall dimensions were measured on histological sections using computer-aided planimetry and immunocytochemistry undertaken for selected parameters. Results: Polyglactin stents significantly reduced medial thickening compared to the All grafts were patent at explantation. Intimal thickness was significantly lower (p < 0.05) in the stented grafts (0.11 0.01 mm) compared to the unstented controls (0.18 0.01 mm). Similarly, medial thickness was significantly lower (p < 0.05) in the stented grafts (0.24 0.03 mm) compared to the unstented controls (0.43 0.04 mm) mm. Grafts externally supported with polyglactin had a pronounced increase in inflammatory cells (in particular, giant cells) around the biodegradable stent compared to both unstented controls and previously studied Dacron stented grafts. The space between graft and stent had become organised into a neo-adventitia with abundant microvessels which stained positively for VEGF and lectin (markers of micorvessels and endothelial cells). Conclusions: An over-size biodegradable stent reduces medial thickening, a component of late vein graft failure in experimental grafts. If subsequent studies confirm the preservation of this beneficial effect when the stent biodegrades completely, this form of stent may have an advantage over permanent stent material in the clinical use of external stenting to prevent vein graft thickening and failure. [source]

Coronary Flow Reserve by Transthoracic Echocardiography Predicts Epicardial Intimal Thickening in Cardiac Allograft Vasculopathy

F. 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]

Reassessing the Cardiovascular Risks and Benefits of Thiazolidinediones

Andrew Zinn MD
Abstract This article is designed for the general cardiologist, endocrinologist, and internist caring for patients with diabetes and coronary artery disease. Despite the burden of coronary disease in diabetics, little is known about the impact of commonly used oral hypoglycemic agents on cardiovascular outcomes. As the untoward effects of insulin resistance (IR) are increasingly recognized, there is interest in targeting this defect. Insulin resistance contributes to dyslipidemia, hypertension, inflammation, hypercoagulability, and endothelial dysfunction. The aggregate impact of this process is progression of systemic atherosclerosis and an increased risk of adverse cardiovascular outcomes. As such, much attention has been paid to the peroxisome-proliferator-activated receptor gamma (PPARg) agonists rosiglitazone and pioglitazone (thiazolidinediones [TZDs]). Many studies have demonstrated a beneficial effect on the atherosclerotic process; specifically, these agents have been shown to reduce markers of inflammation, retard progression of carotid intimal thickness, prevent restenosis after coronary stenting, and prevent cardiovascular death and myocardial infarction in 1 large trial. Such benefits come at the risk of fluid retention and heart failure (HF) exacerbation, and the net effect on plasma lipids is still poorly understood. Thus, the aggregate risk-benefit ratio is poorly defined. A recent meta-analysis has raised significant concerns regarding the overall cardiovascular safety of 1 particular PPARg agonist (rosiglitazone), prompting international debate and regulatory changes. This review scrutinizes the clinical evidence regarding the cardiovascular risks and benefits of PPARg agonists. Future studies of PPARg agonists, and other emerging drugs that treat IR and diabetes, must be designed to look at cardiovascular outcomes. Copyright 2008 Wiley Periodicals, Inc. [source]

Endothelial dysfunction, subangiographic atheroma, and unstable symptoms in patients with chest pain and normal coronary arteriograms

Jonathan 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]

Obese children show increased intimal wall thickness and decreased pulse wave velocity

Frida Dangardt
Summary Objective:, Childhood obesity confers an increased risk of vascular changes and adult cardiovascular disease. Using a high-resolution ultrasound technique that enables separation of intimal and medial layers, we examined the intimal thickness (IT) and intimal,medial thickness (IMT) of radial (RA) and dorsal pedal (DPA) arteries and the pulse wave velocity (PWV) in overweight/obese children and adolescents and in healthy subjects. Methods and results:, IT and IMT of RA and DPA and PWV were measured in 33 obese children and adolescents (139 16 years) and in 18 matched lean controls (143 22). Increased RA IT was found in the obese group, whereas no differences in RA IMT or medial thickness were observed. Obese females accounted for the entire difference in RA IT (P = 004). DPA IT was inversely correlated with HDL cholesterol in the obese group (,056, P = 00089). PWV was lower in the obese group than in the lean group (62 08 versus 70 09 m s,1, respectively; P = 0001). Conclusions:, Obese children and adolescents, primarily females, present with increased RA IT. The decreased PWV in the obese versus lean subjects might reflect general vasodilatation. [source]