Usefulness of multidetector CT imaging to assess vascular stents in children with congenital heart disease: An in vivo and in vitro study

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.     

Role of endothelin in diabetic vascular complications

Endothelin-1 (ET-1), a 21 amino acid peptide originally purified from conditioned medium of cultures of porcine aortic endothelial cells, is recognized as a product of many other cells as well. It is now known that there are three endothelin genes in the human genome (ET-1, ET-2, and ET-3). ET-1 and ET-2 are both strong vasoconstrictors, whereas ET-3 is a potentially weaker vasoconstrictor than the other two isoforms. Besides being the most potent vasoconstrictor yet known, ET-1 also acts as a mitogen on the vascular smooth muscle, and, thus, it may play a role in the development of vascular diseases. It is well known that accelerated angiopathy is a major complication in diabetes mellitus. As generalized endothelial cell damage is thought to occur in diabetic patients, ET-1, being released from the damaged endothelial cells, is able to make contact with the underlying vascular smooth muscle cells and thus could be one important cause of diabetic angiopathy. This article summarizes the reported literature of the role of ET-1 in the development of diabetic complications, with particular focus on the possible role of Et-1 in mediating the effects of angiotensin-converting enzyme inhibitors.     

Application of intraluminal ultrasound imaging to vascular stenting

Summary Over the past few years catheter-based intraluminal ultrasound (IVUS) has emerged as a promising and imaginative technique which can significantly extend our understanding of atherosclerotic lesions both before and following interventions. In relation to stent implantation intravascular ultrasound appears well suited as an imaging modality — providing information as to lumen shape lesion surface and topography, as well as wall composition. To this end arteriography is unable to provide such detailed information. The purpose of this review is to outline the characteristics of stents and endoluminal support devices, currently under investigation, and the role of ultravascular ultrasound in this respect.     

Prognostic implications of vascular complications following PCI

Objectives: To evaluate the effect of vascular complications (VC) on the adjusted risk of nonfatal myocardial infarction (MI) or death following percutaneous coronary intervention (PCI) at 1 year in a large contemporary cohort. Background: Peri‐procedural bleeding increases the risk of adverse clinical outcomes at 1 year. Whether access site VC's identify patients at high risk or independently alter the risk of adverse clinical outcomes at 1 year, however, is uncertain. Methods: 3,931 PCI procedures performed via a femoral access at a single site (WFUBMC) were evaluated. Access and nonaccess site post procedural bleeding were assessed. The adjusted risk of access site VC's association with 1‐year clinical outcomes was evaluated by Cox proportional hazards modeling. Results: Any VC occurred in 1.7%, and any TIMI bleeding in 6.7% after PCI. The hazard ratio (HR) adjusted for baseline and procedural covariates for any VC of nonfatal MI or all cause death at 1 year was 1.68 (1.00–2.81), P = 0.049 and 1.69 (0.92–3.09), P = 0.088 for all cause death alone. However, after adjusting for any TIMI bleeding, the HR for nonfatal MI or death was 0.84 (0.49–1.45), P = 0.527, and for death alone 0.75 (0.39–1.41), P = 0.369. Conclusions: The occurrence of VC following PCI was an independent predictor of nonfatal MI or death at 1 year, but only if accompanied by TIMI major or minor bleeding. A vascular complication without TIMI bleeding did not alter prognosis at 1 year. © 2009 Wiley‐Liss, Inc.     

细胞焦亡与糖尿病血管并发症关系的研究进展

糖尿病血管病变是主要的糖尿病慢性并发症,是导致患者生活质量下降和预期寿命缩短的最主要原因。细胞质内模式识别受体(PRRs)可感受多种刺激形成炎性小体,激活焦亡通路,加重糖尿病患者代谢紊乱,促进糖尿病血管并发症的发生发展。本文浅谈细胞焦亡对不同糖尿病血管并发症的促进作用,以及抑制焦亡通路可能为糖尿病血管并发症的早期诊治提...     

血管性痴呆的扩散张量成像研究

目的应用扩散张量成像(DTI)技术,探讨皮质下缺血性血管性痴呆(SIVD)患者脑白质变化的特点及不同脑区DTI参数改变与认知的关系。方法对34例SIVD患者(SIVD组)及26例健康老年人(对照组)行DTI扫描,测量双侧前额叶、额叶深部、眶额内侧、下额叶、颞叶、顶叶、枕叶白质及T_2WI高信号区、T_2WI高信号周围正常白质区的分量各向异性(FA)、主各向异性(PA)及表观弥散系数(ADC)值。结果对照组左侧前额叶白质PA值大于右侧,ADC值小于右侧。SIVD组双侧前额叶、双侧额叶深部、下额叶、眶额内侧的FA值及PA值明显下降,平均ADC值升高;双侧顶叶的FA值下降,平均ADC值升高;双侧颞叶、枕叶平均ADC值升高;左侧下额叶、眶额内侧白质的FA与PA值较右侧小;左侧下额叶ADC值较右侧大。病变区及病变周围区的FA和PA值小于正常区,ADC值大于正常区。前额叶FA与简易智能状态检查表评分呈正相关。结论 SIVD患者脑白质FA、PA和ADC改变具有区域选择性,前部及左侧脑区损伤明显,后部及右侧相对保留白质的完整性。DTI是研究SIVD脑白质损伤的一种理想的方法。     

亚临床甲状腺功能减退症对糖尿病血管并发症的影响

糖尿病和甲状腺功能障碍是常见的内分泌代谢疾病,糖尿病患者中合并甲状腺功能异常者越来越多,其中以亚临床甲状腺功能减退症居多.目前大多数研究认为,亚临床甲状腺功能减退症可通过引起血脂紊乱、血流动力学异常及内皮功能紊乱等机制,参与并加重糖尿病微血管及大血管并发症.     

抑瘤素M与糖尿病及其血管并发症

抑瘤素M(OSM)是白细胞介素-6超家族成员,是一种多功能的细胞因子,参与细胞生长、分化、炎性反应、造血过程以及组织重塑等多种生物学过程.近年来研究发现,OSM与糖尿病及其血管并发症密切相关,确切的机制尚不清楚,可能是通过自分泌和旁分泌的方式,促进自身和其他细胞因子的分泌,参与胰岛素抵抗、肥胖等的发生,从而导致糖尿病及其血管损伤.     

高尿酸血症与糖尿病及其血管并发症

高尿酸血症与糖尿病密切相关,同时参与糖尿病性心血管疾病以及糖尿病肾病的发生和发展。高尿酸血症主要是通过导致胰岛素抵抗参与糖尿病的发生,同时通过引起内皮功能损伤、诱发炎症反应等参与糖尿病性心血管疾病以及糖尿病性。肾病的发生。本文主要探讨高尿酸血症与糖尿病及其血管并发症的发病情况及可能的发病机制。     

Therapy for acute vascular complications in percutaneous transluminal coronary angioplasty with the autoperfusion balloon catheter.

Prolonged dilatation with an autoperfusion balloon catheter (APBC) (High-Flow-CPC-Mainz (Schneider) in 23 cases and Stack Perfusion (ACS) in 50 cases) was carried out in 73 patients (60 men, 13 women, mean age 59.3 +/- 8.8 years) with acute vascular complications occurring during PTCA (25 occlusive dissections (34%), five thrombotic occlusions (7%), 42 non-occlusive dissections (58%) and one non-occlusive thrombus with reduction of flow (1%)) in order to avoid stent implantation or emergency bypass surgery. On average 1.5 +/- 0.8 inflations were carried out per patient with a mean maximum inflation time of 14.1 +/- 8.4 min and a mean total inflation time of 16.8 +/- 12.3 min. In 61 patients (83.5%), the vascular complication could be controlled successfully with APBC, but in 12 APBC was not successful. Eight patients (11%) had emergency surgery. A stent was implanted in three patients (4.1%), and one suffered an acute myocardial infarction. Out of the 61 patients with positive result after prolonged dilatation, the hospital phase was uncomplicated in 53 (86.9%), five (8.2%) suffered an infarct with a maximum rise in CK of 350 U.l-1, two with multivessel disease had elective operations and one was dilated a second time because of a subacute reocclusion. Our experience indicates that when an acute vascular complication occurs, prolonged dilatation with an APBC is good interventional therapy avoiding stent implantation or emergency bypass surgery. However, new techniques cannot always replace surgery so an emergency bypass operation may still be necessary.     

Increased risk for vascular complications in PRV-1 positive patients with essential thrombocythaemia

Essential thrombocythaemia (ET) is a heterogeneous disorder with respect to plasma erythropoietin concentration at diagnosis and clonality of haematopoiesis. Polycythaemia rubra vera-1 (PRV-1) positivity, i.e. PRV-1 mRNA overexpression, is known to be present in the vast majority of patients with polycythaemia vera and also in some patients with ET. In the present study, PRV-1 expression was quantified by real-time polymerase chain reaction in 70 ET patients; 17 of them (24%) were found to be PRV-1 positive. Ten of the 17 PRV-1 positive ET patients had experienced thromboembolic complications compared with 14 of 53 PRV-1 negative patients, the difference between the two groups being statistically significant (P=0.02). In addition, the frequency of total vascular complications, thromboembolic events and major bleedings, was significantly higher in the group of PRV-1 positive as compared with PRV-1 negative ET patients (P=0.03). The time from diagnosis of ET to the requirement of platelet-lowering therapy was significantly shorter in PRV-1 positive compared with PRV-1 negative ET patients (P=0.014). It can be concluded that PRV-1 positive patients appear to suffer from a more aggressive disorder with increased risk for vascular complications and a greater need for platelet-lowering therapy, compared with PRV-1 negative ET patients.     

Impact of vascular complications after transcatheter aortic valve implantation. VASC-OBSERVANT II sub-study

Background

Trans-femoral (TF) access is the commonest approach for transcatheter aortic valve implantation (TAVI). However this vascular approach is associated with vascular complications (VC) which in turn have prognostic implications. The aim of this study is to evaluate the clinical impact of access site VC in patients undergoing TAVI with newer generation transcatheter prostheses enrolled in the national observational prospective multicenter study OBSERVANT II.

Methods

Vascular events were defined according to the Valve Academic Research Consortium (VARC)-2 criteria. The population enrolled in OBSERVANT II was divided into 3 groups: patients without VC (No-VC), patients with minor VC or percutaneous closure device failure (Minor-VC) and patients with major VC (Major-VC). The primary endpoint was 1-year major adverse cardiac and cerebrovascular event (MACCE), a composite endpoint of all-cause mortality, stroke, myocardial infarction and coronary revascularization. A multivariate Cox regression model was used for risk estimation of MACCE between the three analyzed groups.

Results

2.504 patients were included in this analysis: 2.167 patients in No-VC group; 249 patients in the Minor-VC and 88 patients in the Major-VC. At 1-year Minor-VC group had a freedom from MACCE comparable to the No-VC group, while Major-VC patients had significantly worse outcome (Log-rank test: p = 0.003). These results were driven by higher 1-year mortality in the Major-VC (p < 0.0001). Major-VC was an independent predictor of MACCE in adjusted analysis (hazard ratio 1.89, 95% confidence interval 1.18-3.03, p = 0.008).

Conclusions

Despite a low incidence of major VC with current TF-TAVI devices, our data confirm that major VC is still associated with a significantly worse clinical outcome.     

Foot complications in Type 2 diabetes: an Australian population-based study.

AIMS: To determine the prevalence and risk factors for neuropathy and peripheral vascular disease (PVD) in the Australian diabetic population and identify those at high risk of foot ulceration. METHODS: The Australian Diabetes Obesity and Lifestyle study included 11 247 adults aged >or= 25 years in 42 randomly selected areas of Australia. Neuropathy and PVD were assessed in participants identified as having diabetes (based on self report and oral glucose tolerance test), impaired fasting glucose, impaired glucose tolerance and in a random sample with normal glucose tolerance (total n = 2436). RESULTS: The prevalence of peripheral neuropathy was 13.1% in those with known diabetes (KDM) and 7.1% in those with newly diagnosed (NDM). The prevalence of PVD was 13.9% in KDM and 6.9% in NDM. Of those with diabetes, 19.6% were at risk of foot ulceration. Independent risk factors for peripheral neuropathy were diabetes duration (odds ratio (95% CI) 1.73 (1.33-2.28) per 10 years), height (1.42 (1.08-1.88) per 10 cm), age (2.57 (1.94-3.40) per 10 years) and uric acid (1.59 (1.21-2.09) per 0.1 mmol/l). Risk factors for PVD were diabetes duration (1.64 (1.25-2.16) per 10 years), age (2.45 (1.86-3.22) per 10 years), smoking (2.07 (1.00-4.28)), uric acid (1.03 (1.00-1.06) per 0.1 mmol/l) and urinary albumin/creatinine ratio (1.11 (1.01-1.21) per 1 mg/mmol). CONCLUSIONS: The prevalence of neuropathy and PVD was lower in this population than has been reported in other populations. This may reflect differences in sampling methods between community and hospital-based populations. Nevertheless, a substantial proportion of the diabetic population had risk factors for foot ulceration.     

Vascular complications post-transcatheter aortic valve procedures

Transcatheter aortic valve replacement (TAVR) has rapidly emerged as the standard of care for severe symptomatic aortic stenosis in patients whose comorbidities put them at prohibitive risk for surgical aortic valve replacement (SAVR). Several trials have demonstrated superior outcomes with TAVR compared to medical management alone. TAVR has also shown favorable outcomes in patients at high risk for SAVR. TAVR can be associated with significant vascular complications, which adversely impact outcomes, and operators should be cognizant of their early recognition and appropriate management. In this article, we review the major vascular complications associated with TAVR, along with optimal prevention and management strategies.     

多聚ADP核糖聚合酶-1与糖尿病血管并发症

多聚ADP核糖聚合酶（PARP）1是PARP核酶家族主要成员,分布广泛,是机体修复DNA损伤的关键酶之一,但其过度激活又会造成细胞的死亡。糖尿病时的氧化应激状态可以造成血管内皮细胞内源性DNA损伤,从而大量激活PARP,进而导致内皮细胞的死亡。这是糖尿病大血管和微血管并发症发生的共同机制。抑制PARP可有效防止内皮细胞的损伤,预防甚至逆转糖尿病血管并发症,对PARP的干预可能成为防治糖尿病血管并发症的一个新靶点。     

Twenty-five to forty-five years of diabetes with and without vascular complications

Summary Forty-eight patients with a mean duration of diabetes of 36 years were examined in an attempt to establish the clinical and social factors responsible for this unusually long survival. The exceptional course of these patients was demonstrated by a comparison with 48 matched patients 9 of whom had died within 10 years and 19 within 25 years of the onset of diabetes. — Of the 48 patients examined, 24 had received earlier the Quarter-Century Victory Medal for having passed 25 years of documented diabetes without vascular complications. The remaining 24 Long Term Diabetics were matched to the Medal patients as to sex, age and duration of diabetes. — A striking feature of all 48 patients and especially the Medal group was the low prevalence of large vessel disease. Microangiopathy was more frequent. Thus nonproliferative retinopathy was present in 5 of the Medal patients and in 11 of the Long Term Diabetics. Proliferative retinopathy was found in 10 Long-Term Diabetics, but in none of the Medal patients. Clinical evidence of nephropathy was found in 8 and neuropathy in 28 of the 48 patients. — A relatively high prevalence of parental longevity and a low frequency of obesity and of heavy cigarette smoking, were found in the Medal patients. Other factors apparently contributing to the favourable prognosis in the 48 patients examined included regular sports and other physical activity (93%) and maintenance of fair to good diabetic control (79%). Thirty-five percent of the patients had close relatives in the medical profession.This study was supported in part by grants from the U.S. Public Health Service (AM 04146 and AM 05070), the Massachusetts Lions Eye Research Fund and the John A. Hartford Foundation, Inc., New York N.Y. Dr. Chazan had an Earl Wilson Postdoctoral Research Fellowship of Fight for Sight, New York, N.Y.     

The effect of interferon alpha on myeloproliferation and vascular complications in polycythemia vera

Abstract: The effect of interferon alpha (IFN) on myeloproliferation and vascular complications was studied in 32 patients (17 female, 15 male; median age 60.5 yr) with polycythemia vera (PV). IFN therapy was initiated at a median time of 19 months after diagnosis. Ten patients were pretreated with chemotherapy in addition to phlebotomy. IFN dose was 12 megaU/wk during the first year, 9 megaU/wk during the second year and 12 megaU/wk thereafter. During IFN alpha treatment hematocrit level was 45.7% and remained at this level after the second year of treatment, compared to 46.5% before IFN. The frequency of phlebotomy before IFN was 0.49/month and dropped to 0.19/month (p<0.0005) during the first year of IFN treatment. IFN normalized high platelet and leukocyte counts in a majority of patients. The incidence of deep venous thromboses was 3.6%/yr before IFN alpha and 1.8%/yr during the first year of treatment. IFN-induced side-effects were mainly flu-like symptoms, fever, fatigue and arthralgia. In conclusion, IFN allowed the reduction of the dose of chemotherapy and decreased the need of phlebotomy. Despite improvement of hematological parameters, it is still uncertain whether IFN alpha can improve clinical symptoms in PV.