ISRN Vascular Medicine

4-Year Outcome Analysis of Endoscopic Vein Harvesting for Coronary Artery Bypass Grafting

Shahzad G. Raja, Melissa Rochon, Camilla Sproson, and Toufan T. Bahrami — Wed, 20 Mar 2013 17:57:02 +0000

Objective. Despite increasing recognition that endoscopic vein harvesting (EVH) is associated with decreased leg wound morbidity, improved cosmetic results, and enhanced patient satisfaction, concerns persist regarding the safety and efficacy of EVH. This study compares in-hospital and midterm outcomes for EVH and open vein harvesting (OVH) at our institution. Methods. 772 patients with EVH were propensity matched to 772 patients who had OVH. Their data were prospectively entered into the cardiac surgery database (PATS; Dendrite Clinical Systems, Ltd., Oxford, UK) and analyzed, retrospectively. The mean duration of followup was 26.4 ± 10.3 months. Results. EVH was associated with a significant reduction in rate of donor site infection compared to OVH (0.39% versus 3.9%, ). Short- and medium-term vein graft patency was similar. After adjusting for clinical covariates, EVH did not emerge as an independent predictor of readmission to hospital for cardiac causes (odds ratio (OR) 1.19, 95% confidence interval (CI) 0.96–1.58, and ), medium-term mortality (hazard ratio (HR) 1.28, 95% CI 1.09–1.42, and ), and need for reintervention (HR 1.21, 95% CI 0.98–1.32, and ). Risk-adjusted survival was 94% for EVH patients and 93% for OVH patients () during the medium-term followup. Conclusion. Our analysis confirms the short- and midium-term safety and efficacy of EVH.

The SAAAVE Act and Routine Ambulatory Medical Care Fail to Diagnose Patients with Abdominal Aortic Aneurysms prior to Rupture: A Single-Institution Experience

Tue, 12 Feb 2013 14:18:34 +0000

Objectives. To demonstrate that routine ambulatory medical evaluation in the outpatient setting and current utilization of the Screening Abdominal Aortic Aneurysms Very Efficiently (SAAAVE) Act are inadequate methods to diagnose abdominal aortic aneurysms (AAA) prior to rupture. Methods. A retrospective review was performed on patients with ruptured AAA (rAAA) at a single institution. All patients who were evaluated in an ambulatory care setting within 6 months of the date of rupture were identified, and clinical data were analyzed. Results. Between January 1, 2004 and December 31, 2010, there were 149 patients with rAAA. Fifty-two of 149 (34.9%) patients were evaluated in the outpatient setting within 6 months prior to the date of rupture, and these patients form the basis of this study. Thirty-six of 52 (70%) patients were male, average age was 73.5 years, average BMI was 28, and average aneurysm diameter was 76 mm. Only 5/52 (9.6%) patients had physical exam findings suspicious for AAA. Only 9/52 (17%) would have been eligible for the screening abdominal ultrasound under the SAAAVE Act. Conclusions. Routine medical evaluation in the ambulatory care setting and current utilization of AAA screening methods are inadequate at detecting AAA in the at-risk population prior to rupture.

Does Restenosis Still Hamper the Benefit of Carotid Artery Revascularization?

C. J. de Witte, G. W. van Lammeren, F. L. Moll, and G. J. de Borst — Tue, 12 Feb 2013 11:14:45 +0000

Both carotid endarterectomy (CEA) and carotid artery angioplasty with stenting (CAS) may offer acceptable short-term results in symptomatic or asymptomatic patients with carotid stenosis. Independent on the type of revascularization, the long-term benefit may be limited by recurrent stenosis, especially after endovascular treatment. Pathophysiological studies suggest that atherosclerotic plaque composition is an independent predictor of restenosis. Identification of certain plaque characteristics could help risk stratify patients in order to decide on the best therapy and minimize the risk of restenosis. Although currently no gold standard exists for the approach of recurrent carotid stenosis, both redo CEA and CAS seem safe therapeutic options. Limited data are available on treatment of recurrent carotid in-stent stenosis. More data are required in order to recommend the best therapy for in-stent restenosis.

Inflammatory Burden but Not Diabetes Mellitus Influences in Prognosis of Endovascular Revascularization in Peripheral Arterial Disease

Thu, 07 Feb 2013 16:10:00 +0000

Aims. To determine the effect of inflammatory preoperative burden on the incidence of reintervention and mortality after endovascular therapy (EVT) and to investigate if diabetes mellitus (DM) is involved in these results. Material and Methods. A prospective cohort study with 12-month follow-up period in patients with peripheral artery disease was carried out. hsCRP and fibrinogen assessments were determined. Results. 85 diabetic and 58 nondiabetic patients were included. An increase between basal hsCRP (11.8 mg/L (10.2; 21.5) versus 4.3 mg/L (1.8; 13.9), ) and fibrinogen levels (450 mg/dL (425; 479.1) versus 369 mg/dL (268; 419), ) and the incidence of death during followup was found. A significant increase between higher hsCRP and fibrinogen basal levels and the incidence of reintervention during the follow-up period was also noted ( and , resp.,). There was no difference between DM and non-DM patients in the 1-year need of reintervention (33.3% versus 45%, , resp.,). Basal hsCRP and fibrinogen levels did not significantly differ between DM and non-DM patients who needed reintervention. Conclusions. The prognosis of the EVT is likely marked by the previous inflammatory load, regardless of DM.

Acute Effects of Two Angiotensin Receptor Blockers on Vascular Hemodynamics, Arterial Stiffness, and Oxidative Stress in Patients with Mild to Moderate Hypertension: An Open Label Parallel Group Study

Wed, 30 Jan 2013 07:57:25 +0000

Introduction. We studied the acute effects of Olmesartan and Telmisartan at baseline and at the end of four weeks on indices of hemodynamics (heart rate HR, blood pressure BP), vascular (carotid femoral pulse wave velocity cf PWV, digital arterial tone expressed as Reflection index RI, and endothelial dependent vasodilator response EDVR), and oxidative stress (serum Malondialdehyde MDA) in hypertensive patients. Materials and Methods. The eligible patients were randomly allocated to either 20 mg Olmesartan or 40 mg Telmisartan. Results. 40 subjects received Olmesartan, and 29 received Telmisartan. After four weeks of treatment the mean changes from baseline in the Olmesartan group versus Telmisartan group are SBP versus mm Hg, ; DBP versus mm Hg, ; cf PWV versus m/s, ; EDVR versus %, ; and MDA versus ηMol/mL, . Conclusion. Olmesartan showed a better improvement in cf PWV, EDVR, and MDA than Telmisartan with an identical reduction in blood pressure.

Associations between Pulse Wave Velocity, Aortic Vascular Calcification, and Bone Mineral Density in Chronic Hemodialysis Patients and General Population

P. Avramovski, P. Janakievska, M. Koneska, K. Sotiroski, and A. Sikole — Sun, 27 Jan 2013 15:28:38 +0000

The aims of this study were to compare PWV, vascular calcification (VC), and bone mineral density (BMD) in chronic hemodialysis patients (CHP) with those of the general population patients (GPP). We evaluated 60 GPP (aged ) compared with 80 CHP (aged ). PWV was determined from time diversity propagation of the carotid and femoral artery by Doppler ultrasound. Lateral lumbar radiography (LLR) of the abdominal aorta was used to determine the overall abdominal aortic calcification (AAC) score. BMD of the hip and the spine was assessed by dual energy X-ray absorptiometry (DEXA). Biochemical parameters (PTH, Ca2+, P, albumin, CRP, etc.) were determined in all participants according to standard laboratory procedures. The mean PWV was m/s in the GPP and m/s in the CHP. The mean AAC score was as follows: GPP: , CHP: . The mean BMD at hip was as follow: GPP: (g/cm2), CHP: (g/cm2). In the GPP, PWV correlate with VC (), BMD (), albumin (), and CRP (). In the CHP, PWV correlates with VC (), BMD (), albumin (), and CRP (). There is a strong inverse correlation between PWV and BMD and between VC and BMD. There is a positive correlation between PWV and VC.

MicroRNAs in Cardiovascular Regenerative Medicine: Directing Tissue Repair and Cellular Differentiation

Joost P. G. Sluijter — Wed, 16 Jan 2013 15:06:33 +0000

MicroRNAs (miRNAs) are a class of short noncoding RNA molecules, approximately 22 nucleotides in length, which regulate gene expression through inhibition of the translation of target genes. It is now generally accepted that miRNAs guide processes and cellular functions through precise titration of gene dosage, not only for a single gene but also controlling the levels of a large cohort of gene products. miRNA expression is altered in cardiovascular disease and may thereby limit and impair cardiovascular repair responses. Increasing evidence of the essential role of miRNAs in the self-renewal and differentiation of stem cells suggests the opportunity of using the modulation of miRNA levels or their function in directing cell transplantation, cell behavior, and thereby organ healing. In this paper, an overview of miRNA biogenesis and their way of action and different roles that miRNAs play during the myocardial responses to injury and upon cell transplantation will be provided. We focused on cardiomyocyte survival, angiogenesis, extracellular matrix production, and how miRNAs can direct cell plasticity of injected cells and thus drive differentiation for cardiovascular phenotypes, including vascular differentiation and cardiomyocyte differentiation.

Intracoronary Imaging and Histopathology of Late Phase In-Stent Restenosis after Coronary Stent Implantation

Sun, 23 Dec 2012 10:22:29 +0000

In the field of coronary artery stenting, restenosis issue has been almost resolved after development of drug-eluting stents (DESs). In-stent restenosis (ISR) is generally considered to be a stable process, with an early peak in intimal hyperplasia followed by a quiescent period beginning 1 year after stent implantation. However, recently, extended-term problem (over 1 year) in both bare-metal stents (BMSs) and DES has been reported. This phenomenon seems to be different from early ISR within one year in terms of its mechanism, prevention, and treatment. In this paper, we discuss this topic from the standpoint of intracoronary imagings and histopathology, referencing several interesting cases we experienced.

Mild External Compression of the Leg Increases Skin and Muscle Microvascular Blood Flow and Muscle Oxygenation during Simulated Venous Hypertension

T. B. Neuschwander, B. R. Macias, A. R. Hargens, and Q. Zhang — Mon, 10 Dec 2012 15:27:35 +0000

We studied the effect of mild external leg compression on both skin and muscle microvascular flow, and muscle oxygenation in the leg of healthy subjects during simulated venous hypertension. Skin and muscle microvascular blood flows were measured using photoplethysmography (PPG), and muscle oxygenation was measured using near-infrared spectroscopy (NIRS). Both PPG and NIRS probes were placed over the anterior compartment of the right leg in 8 healthy subjects. Measurements were taken under three experimental conditions: external leg compression (40 mmHg); simulated venous hypertension (65 mmHg thigh cuff); external leg compression during simulated venous hypertension. Muscle oxygenation was measured only under external leg compression during simulated venous hypertension. Simulated venous hypertension decreased skin and muscle microvascular blood flows from 100% (baseline) to % and % (), respectively. External leg compression during simulated venous hypertension caused 2-fold increases in both skin and muscle microvascular blood flows compared to simulated venous hypertension (). Similarly, external leg compression during simulated venous hypertension significantly restored muscle oxygenation by % compared to its baseline (). Our results demonstrate that mild external leg compression counteracts the decreases in skin microvascular flow, muscle microvascular flow, and muscle oxygenation induced by simulated venous hypertension in the leg.

Targeted Treatments for Restenosis and Vein Graft Disease

Anita C. Thomas — Sun, 09 Dec 2012 14:00:35 +0000

Surgery to restore blood flow in arteries blocked by atherosclerotic plaque is a common treatment in cardiovascular disease. Long-term complications of surgical treatment are vein graft disease and restenosis, a renarrowing of the blood vessel after bypass or removal of the culprit atherosclerotic plaque. Attempts to prevent or treat these complications by systemic pharmacological approaches have been largely unsuccessful in the clinic. This has led to an interest in developing targeted or locally delivered strategies. This paper discusses many of the various site-delivered therapies that are under examination as potential antirestenotic and antivein graft disease agents (including antithrombotic, antiproliferative, and anti-inflammatory agents) and why many therapies developed in animal models fail in clinical trials. Techniques of targeted delivery (including stents, “magic bullets,” and adventitial delivery) and delivery systems (including nanoparticles and the use of gene therapy) are also discussed.

Endothelial Nitric Oxide Synthase (NOS3) +894 G>T Associates with Physical Activity and Muscle Performance among Young Adults

Thu, 29 Nov 2012 15:13:39 +0000

Objective. We examined the influence of missense polymorphism, endothelial nitric oxide synthase (NOS3) +894 G>T (rs1799983), on habitual physical activity (PA) and the muscle strength response to resistance training (RT). Methods. Men () and women (; yr) were genotyped. Subjects reported hr/wk in vigorous and light intensity PA and sitting on the Paffenbarger PA questionnaire. One repetition maximum assessed muscle strength. Multivariable and repeated measures ANCOVA tested differences among NOS3 +894 G>T and PA and RT phenotypes by gender. Results. hr/wk in vigorous intensity PA ( versus ; ), more hr/wk in light intensity PA ( versus ; ), and less hr/wk sitting ( versus ; ) than those with the G allele. Women with NOS3 +894 TT gained more absolute ( versus kg; ) and relative ( versus %; ) strength than those with the G allele. Conclusions. NOS3 +894 G>T associated with PA among men and women and the muscle strength response to RT among women only. Our findings indicate the need for prospective studies examining the influence of NOS3 variants on PA and the muscle response to RT as well as elucidating underlying mechanistic pathways for the associations observed.

Transient Left Ventricular Apical Ballooning in a Postmenopausal Woman with Chronic Liver Disease, Malignancy, and Recent Ischemic Stroke: A Case Report and Review of the Literature

Dustin Covell and Nathan Clendenen — Sun, 25 Nov 2012 12:11:17 +0000

Transient left ventricular apical ballooning (TLVAB), or Takotsubo cardiomyopathy, is a poorly understood phenomenon that is thought to be related to a surge of catecholamines under stress conditions that causes microvascular dysfunction and a unique pattern of myocardial stunning. TLVAB occurs in two distinct patient populations: (i) community presentation similar to acute coronary syndrome and (ii) the critically ill. Understanding the differences in presentation, prognosis and management between these two groups may improve the outcome. We present a case of TLVAB developing in a Caucasian postmenopausal female who developed TLVAB suddenly on a background of chronic liver disease, malignancy, and recent ischemic stroke. The patient presented with hemodynamic collapse and was treated with inotropes, vasopressors, and supportive care until cardiac function improved. Additionally, we review the current literature describing the risk factors, pathophysiology, and treatment of TLVAB.

Pro- and Anti-Inflammatory Cytokine Networks in Atherosclerosis

Michael V. Autieri — Mon, 19 Nov 2012 08:43:08 +0000

Despite advances in prevention and treatment, atherosclerotic vascular disease continues to account for significant morbidity, mortality, and economic burden in the western world. Our current understanding of this disease presents atherosclerosis as a chronic inflammatory process involving multiple cell types in various stages of activation, apoptosis, and necrosis. These cells include monocyte/macrophage, dendritic cells, lymphocytes, endothelial cells, and vascular smooth muscle cells. Activation of these cells and their processes is initiated and sustained by a complex network of soluble factors termed cytokines. Cytokines are produced and recognized by both inflammatory and resident vascular cells, allowing crosstalk between these two systems. Cytokines also regulate the phenotype of many of these cell types. Recognizing functions of these cytokines and their effects on cells which populate atherosclerotic plaque is key to uncovering targets of therapeutic intervention. This paper will present recent studies which describe the cellular protagonists of atherosclerosis and the role they play in formation of atherosclerotic plaque. It will also describe the cytokines which have been identified as produced by and directly affecting dysfunction of these cells. Because atherosclerosis is considered an inflammatory condition, emphasis will be placed on inflammatory cytokines and their effects on atherogenesis. We will conclude with new directions in therapeutic strategies and points of emphasis for future research.

Incidence of the Curvature of a Catheter on the Variations of the Inner Volume: Application to the Peripherally Central Catheters

Sun, 18 Nov 2012 16:14:55 +0000

One particular characteristic of peripherally central catheter (PCC), peripherally inserted central catheter (PICC) or totally implantable venous access device (TIVAD), is to be submitted to a rotational movement around the shoulder in the daily routine. The aim of this paper is to show that these movements induce a variation of the inner volume of the catheter which may be responsible for an internal distal pollution of the lumen. The results are presented in the framework of an open discussion on the catheter protocols of use as well as a possible improvement of the materials.

Periprocedural Thromboembolic Events Associated with Angioplasty and Stenting of the Extra- and Intracranial Carotid Artery Assessed by Neurological Status and Diffusion-Weighted Magnetic Resonance Imaging (DWI)

Frank Ahlhelm, Johanna Lieb, Stefan Ulmer, Dirk Ahlhelm, and Wolfgang Reith — Mon, 22 Oct 2012 11:51:02 +0000

Objective. The purpose of this study was to determine the frequency of thromboembolic events associated with angioplasty and stenting of the carotid artery with special regard to extra- or intracranial localization of stenosis. Methods. Twenty patients with symptomatic intracranial or extracranial internal carotid artery stenosis were treated with stenting and/or angioplasty. In 4 patients stenting was technically not feasible (all in the group with intracranial stenosis). All patients underwent diffusion-weighted imaging (DWI) and neurological examination within 48 hours before and after the procedure to detect periprocedural thrombembolic events. Results. Extracranial carotid angioplasty and stenting (eCAS) was technically feasible and successfull without procedure-related neurological complications in all cases. Intracranial stenting (iCAS) was not feasible in four cases including one patient with a fateful course. Concerning the restoration of the vessel diameter intracranial stenting was not as successful as eCAS, but more effective than balloon angioplasty alone. Incidence of thrombembolic events assessed by DWI was low. The detected periprocedural thrombembolic events were small and clinically silent. Conclusion. The risk of thromboembolic events during the endovascular treatment of symptomatic carotid artery stenosis was rather low for intra- and extracranial stenosis of the ICA in our patient sample, but one fatal course was observed.

Metabolic Profiling of Patients Undergoing Elective Aortic Aneurysm Repair Surgery: Correlation with Anaerobic Threshold

Sun, 21 Oct 2012 15:33:49 +0000

The anaerobic threshold (AT) measured by the cardiopulmonary exercise (CPX) test is becoming an established means of identifying patients at high risk of developing cardiac complications perioperatively. The aim of the present study was to investigate the relationship between AT and the plasma metabolic profile of patients undergoing aortic aneurysm repair surgery to see if an alternative or adjunct to the CPX test could be devised. Plasma was obtained from 15 male patients classified (through preoperative CPX tests) as having high (≥11.0 mL kg−1 min−1) or low (<11.0 mL kg−1 min−1) AT before and 1, 2, 24, 48, and 72 hours after elective open aortic aneurysm surgery. Samples were analysed using 1H-NMR spectroscopy coupled with multivariate statistical analysis. Principal components analysis (PCA) and partial least squares discriminant analysis (PLS-DA) distinguished between low- and high-AT patients postoperatively, with high AT patients being more tightly clustered. High AT patients had higher plasma lipid and lower 3-hydroxybutyrate and acetoacetate levels than low AT patients post-operatively. Similar differences were identified preoperatively. 1H-NMR metabolic profiling of plasma has identified molecules whose concentration correlates with AT scores. These may prove a useful biomarker in conjunction with AT in predicting response to major surgical procedures.

Nuclear Magnetic Resonance Spectroscopy in the Detection and Characterisation of Cardiovascular Disease: Key Studies

Warren Yabsley, Shervanthi Homer-Vanniasinkam, and Julie Fisher — Sat, 29 Sep 2012 02:35:33 +0000

Purpose. To review the available literature on the applications of nuclear magnetic resonance (NMR) spectroscopy in cardiovascular disease identification and aetiology. Methods. A systematic literature search of peer-reviewed journals for the period January 2000 to June 2012 was performed using EMBASE and Web of Knowledge (WOK) databases. Several hundred reports were identified. Abstract searching led to the selection of articles included. Results. Numerous studies show the breadth of applications of NMR spectroscopy in relation to cardiovascular disease including lipid and lipoprotein formation, structure, and drug interaction. Lipoprotein and metabolite profiles have been shown to vary with many manifestations of cardiovascular disease. Conclusion. The inherent accuracy and reproducibility of NMR spectroscopy allow subtle differences in lipoprotein and metabolic profiles to be detected. As more information is obtained and cardiovascular disease applications of NMR spectroscopy increase, there is potential that a route towards reducing the burden of this worldwide problem may become evident.

New Alternatives for Atherosclerosis Treatment Based on Immunomodulation

Livan Delgado Roche and Danay Alfonso Hernández — Thu, 13 Sep 2012 10:52:44 +0000

Atherosclerosis and its derived cardiovascular diseases are a leading cause of death in the western world. The treatment of atherosclerosis is currently based on lipid lowering in combination with anti-inflammatory therapies that slow the progression of atherosclerosis. Still, these therapies are not able to fully inhibit the formation or progression of atherosclerotic lesions. Ever since it was first demonstrated that the immunological system plays an important role during atherogenesis, various different immunotherapeutic approaches have been evaluated with promising results. Notwithstanding that, one of the difficulties in developing effective vaccination strategies for atherosclerosis is the selection of a specific target. So far, vaccination strategies have been based on the targeting of lipid antigens, inflammation-derived antigens, and cell-based vaccination strategies. More recently, strategies aimed at blocking the retention of low-density lipoproteins by arterial proteoglycans have emerged as a promising tool. In the study at hand we reviewed the most relevant advances on atherosclerosis immunotherapy cited in the PubMed database from 1980 to 2012.

Preclinical and Clinical Effects of RAS Inhibition with a Focus on Telmisartan

Thomas Unger — Thu, 16 Aug 2012 14:12:45 +0000

Blockade of the renin-angiotensin system with angiotensin II receptor blockers (ARBs) provides blood pressure (BP)-independent effects throughout the cardiovascular (CV) continuum. In the landmark ongoing telmisartan alone and in combination with ramipril global endpoint trial (ONTARGET), telmisartan reduced CV events in patients at high CV risk, similar to the angiotensin-converting enzyme inhibitor, ramipril. This reduction in CV events is a consequence of non-BP effects on disease pathophysiology which have been demonstrated in preclinical and clinical studies. For example, telmisartan significantly reduces markers of inflammation, such as interleukin-6 and C-reactive protein, and improves markers of vascular function, such as pulse wave velocity. Both these are associated with target organ damage. Telmisartan also has numerous potentially beneficial metabolic effects in preclinical studies. Telmisartan reduces markers of renal disease and its progression, left ventricular hypertrophy, and the risk of primary or secondary atrial fibrillation. Many of these effects are shared with other RAS inhibitors. However, several studies indicate differential effects between telmisartan and other ARBs. These differences probably reflect telmisartan’s distinct pharmacologic profile, including the longest plasma half-life, high receptor-binding affinity, and highest lipophilicity of the class. These differences suggest that the results of ONTARGET do not necessarily extrapolate to other ARBs.

African Americans and Peripheral Arterial Disease: A Review Article

Winta Ghidei and Tracie C. Collins — Tue, 07 Aug 2012 08:44:30 +0000

Peripheral arterial disease (PAD)—atherosclerosis of the abdominal aorta and arteries of the lower extremities—affects 12 million Americans. African Americans (AAs) are more than twice as likely as non-Hispanic whites to suffer from PAD. When compared to non-Hispanic whites with PAD, AAs with PAD have more severe disease and a greater reduction in walking distance, speed, and/or stair climbing. AAs with PAD are at increased risk for disease progression and worsening lower limb function. Reasons for the higher risk for disease progression have not been defined. One potential modifiable risk is a lower level of physical activity. Lower levels of physical activity are more common among African American seniors. Walking is a common type of physical activity. The benefits of walking therapy are only realized if the patient adheres to such therapy. Efforts are needed to increase walking in AAs with PAD. Additionally, risk factor management is key to reducing adverse events in AAs with PAD-yet few studies have targeted this high-risk group. In this paper, we discuss the management of PAD in AAs. Identifying current gaps will help to inform clinicians, researchers, and policy makers on next steps in identifying innovative approaches to increase home-based walking and reduce walking impairment in AAs with PAD.

Adiponectin Fails in Improving Angiogenic Repair in Streptozocin-Treated or Leprdb/db Mice after Hind Limb Ischemia

Kurt Belisle, Martin Andrassy, Jochen Schneider, and Stephan Schiekofer — Mon, 30 Jul 2012 14:00:48 +0000

Objectives. Type 1 and 2 diabetes carry risk factors for the development of microvascular diseases with associated impairment of angiogenic repair. Here, we investigated whether adiponectin, an adipocyte-specific adipocytokine with antiatherosclerotic and antidiabetic properties, regulates angiogenic repair in response to tissue ischemia in Leprdb/db and streptozocin-treated diabetic mouse models. Methods. Adenoviral vectors containing the gene for β-galactosidase, full-length mouse adiponectin, and dominant-negative AMPKα2 were used in streptozocin-treated male Leprdb/db mice, after which hind limb blood flow was measured using a laser doppler blood flow analyzer. Results. The angiogenic repair of ischemic hind limbs was impaired in both streptozocin-treated and Leprdb/db mice compared to wild-type mice as evaluated by laser doppler flow and capillary density analyses. Adenovirus-mediated administration of adiponectin accelerated angiogenic repair after hind limb ischemia in WT mice, but not in Leprdb/db mice or mice treated with streptozocin. In vitro experiments using HUVECs highlighted the antiapoptotic and proangiogenic properties of adiponectin but could not demonstrate accelerated differentiation of endothelial cells into tube-like structures at elevated glucose levels. Conclusions. External administration of adiponectin at elevated glucose levels may not be useful in the treatment of diabetes mellitus-related vascular deficiency diseases.

Venous Thromboembolism in Cancer Patients Undergoing Major Abdominal Surgery: Prevention and Management

Bhavana Bhagya Rao, R. Kalayarasan, Vikram Kate, and N. Ananthakrishnan — Tue, 17 Jul 2012 11:13:01 +0000

Cancer is an important risk factor for venous thrombosis. Venous thromboembolism is one of the most common complications of cancer and the second leading cause of death in these patients. Recent research has given insight into mechanism and various risk factors in cancer patients which predispose to thromboembolism. The purpose of this review is to summarize the current knowledge on the prophylaxis, diagnosis, and management of venous thromboembolism in these patients.

Relation of High-Density Lipoprotein Cholesterol and Apoprotein A1 Levels with Presence and Severity of Coronary Obstruction

Mon, 28 May 2012 14:28:50 +0000

The aim of this work was to investigate the relationship between different lipids parameters with presence and severity of coronary obstruction angiographically evaluated. 897 patients (629 men and 268 women) underwent an angiography and blood extraction to determine concentrations of lipid markers: total cholesterol (TC), HDL cholesterol (HDLc), triglycerides, LDL cholesterol (LDLc), apolipoprotein A1 (apoA1), apolipoprotein B100 (apoB), non-HDL cholesterol and total cholesterol/HDLc, apoB100/apoA1 and LDLc/HDLc ratios. Multivariate analysis revealed that low HDLc levels were independently associated with the presence of coronary obstruction (OR: 0.982, 95% CI 0.969–0.996). In relation to severity of coronary stenosis, only apoA1 levels (OR: 0.990, 95% CI 0.980–1.000) and apoB/apoA1 ratio (OR: 3.243, 95% CI 1.095–9.608) were independent predictors. Our study demonstrated that HDLc was the only lipid parameter negatively and significantly associated with the presence of coronary obstruction, whereas apoA1 levels and apoB/apoA1 ratio were independent predictors of stenosis severity.

Coronary Flow in Patients with Three-Vessel Disease: Simulated Hemodynamic Variables in relation to Angiographically Assessed Collaterality and History of Myocardial Infarction

Thu, 05 Jan 2012 11:26:04 +0000

We study patients with stenoses of the left main coronary artery (LMCA), left anterior descending artery (LAD), and left circumflex branch (LCx) and with chronic occlusion of the right coronary artery (RCA), undergoing off-pump coronary surgery. An analog electrical model is used to provide quantitative estimations of the distribution of flows and pressures across the coronary network (in the stenosed native arteries, the collateral branches, the capillary areas, and so forth). The present paper demonstrates that the clinical information collected for the 10 patients included in the study (Rentrop score, history of myocardial infarction, left ventricular ejection fraction (LVEF)) are well correlated with the predicted hydrodynamic data. Patients with a good collaterality (Rentrop score = 3) or patients without anterior myocardial infarction have (i) less severe stenoses on the LMCA, (ii) lower microvascular resistances, (iii) higher grafts flow rates when the revascularization is performed, (iv) higher collateral flow rates towards the territory of the occluded artery, (v) better perfusion of this area, and (vi) better total perfusion of the heart.

Pentraxin 3 Released from Neutrophils Increases Plasma Levels in Patients with Acute Coronary Syndrome

Tue, 13 Dec 2011 08:21:19 +0000

Background. Our recently developed ELISA system for the detection of human pentraxin 3 (PTX3) in plasma has demonstrated that plasma PTX3 levels are increased in patients with unstable angina pectoris. However, the origin of the PTX3 from the ruptured plaque or a systemic process and which cells release PTX3 remain unclear. Methods. Blood samples were taken using an aspiration catheter from the site of the ruptured plaque and from the aorta during acute coronary interventions in 118 patients with acute coronary syndrome. These samples were analyzed for PTX3, and brain natriuretic peptide (BNP) was used as a control. Aspirated thrombi from patients with acute myocardial infarction (AMI) (n = 32) were examined by histological staining. Results. Plasma PTX3 levels were higher in blood samples taken from the site of plaque rupture compared to samples taken from the aorta (5.61±1.91 ng/mL versus 4.72 ± 5.61 ng/mL, 𝑃<0.05). On the other hand, BNP levels, as reference, were not different between the samples (P = 0.45). PTX3-positive neutrophils accounted for 70.4% of cells in harvested thrombi, with the remaining cells consisting of mononuclear cells. Conclusions. Infiltrating neutrophils in thrombi at the plaque rupture site are a diagnostically important source of PTX3 in patients with acute coronary syndrome.

Risk Stratification by Cardiac Biomarkers following Emergency Gastrointestinal Surgery

Mon, 12 Dec 2011 10:18:35 +0000

Perioperative cardiac complications are a major cause of death following emergency gastrointestinal surgery. Early diagnosis of subclinical myocardial injury and infarction may be improved by screening with cardiac biomarkers. The aim of this study was to assess the predictive value of troponin I (TnI) and B-type natriuretic peptide (BNP) in the early postoperative period after emergency gastrointestinal surgery. We prospectively recruited 48 patients undergoing major emergency surgery for gastrointestinal or colorectal pathology in a single district general hospital. The primary endpoint was mortality at 90 days following surgery. Overall survival was 81.3% (39/48), with 9 postoperative deaths. Elevated TnI (≥0.03 ng mL−1) was the best predictor of mortality, associated with an odds ratio of death by 90 days of 14.3 (95% CI 1.50–337, 𝑃=0.01). A postoperative BNP concentration >408.5 pg mL−1 was associated with an odds ratio of death by 90 days of 13.6 (95% CI 2.03–106, 𝑃=0.002). A single measurement of postoperative BNP and TnI is a powerful predictor of short- to medium-term mortality in patients after emergency gastrointestinal surgery. Further work is required to demonstrate that cardiac biomarkers have independent predictive power and that patient outcomes can be improved.

Aspirin in Neurology

Yolanda Aburto-Murrieta, Dulce Bonifacio-Delgadillo, and Juan Marquez — Sun, 11 Dec 2011 13:09:54 +0000

Aspirin is widely used for the prevention of recurrent stroke in patients with transient ischaemic attack (TIA) of arterial origin, because it is effective and inexpensive. Clopidogrel and the combination of aspirin and extended-release dipyridamole are more effective than aspirin, but are also much more expensive. No other antithrombotic regimens provide significant advantages over aspirin, although cilostazol and the novel platelet protease-activated receptor-1 antagonist, SCH 530348, are currently being evaluated. Numerous trials have examined the efficacy of antiplatelet drugs, primarily aspirin for prevention of vascular events in patients with a prior TIA or stroke. Although many were small and inconclusive, the Antiplatelet Trialists’ Collaboration (ATC) individual patient data meta-analysis reported that among more than 23000 patients (from 21 randomized controlled trials), antiplatelet therapy (usually aspirin) compared with placebo or untreated control continued for a mean of 29 months was associated with a 22% reduction in the odds of recurrent ischemic stroke, myocardial infarction (MI), or vascular death (17.8% versus 21.4%, 𝑃=0.001).

Resistance of Platelets in Hypercholesterolemia to Inhibition by Activated Coagulation Factor X

Nighat Kahn, Bilal Khan, and Asru K. Sinha — Wed, 30 Nov 2011 10:47:00 +0000

Platelet hyperactivity may be involved in the pathogenesis of both thrombogenesis and hypercholesterolemia. The cholesterol-enriched states may contribute to accelerated development of atherosclerosis. The effect of high cholesterol on platelet activation and on inhibition by coagulation factor Xa, was studied in vitro. Incubation of normal platelets (𝑛=20) with cholesterol-rich dispersion resulted in a small increase of platelet aggregation (PA) and thromboxane A2 (TXA2) synthesis when compared with platelets incubated with cholesterol-normal dispersion. In hypercholesterolemic patients (𝑛=20), ADP-induced PA and TXA2 synthesis showed only small increases over normal controls. Addition of factor Xa (1 unit/mL) prevented the ADP-induced PA and markedly inhibited TXA2 synthesis in normal platelets (1.3±0.2 and 8.7±2.0 pmol TXA2/108 platelets, with and without factor Xa, resp.). However, factor Xa failed to significantly suppress TXA2 synthesis in cholesterol-incubated normal platelets (9.5±1.4 and 11.8±1.3 pmol TXA2/108 platelets, with and without factor Xa; resp., 𝑃=NS) as well as in platelets from patients with hypercholesterolemia (8.6±4.0 and 10.9±4.9 pmol TXA2/108 platelets, with and without factor Xa; resp., 𝑃=NS). Exposure of platelets to high cholesterol concentrations, in vitro and in vivo, marginally increased PA and TXA2 synthesis but resulted in loss of responsiveness to factor Xa, which could significantly contribute to platelet activation in hypercholesterolemic states.

Predisposing Factors for Deep Venous Thrombosis in Children and Adolescents with Nephrotic Syndrome

Gabriela de Toledo Passos Candelaria and Vera Maria Santoro Belangero — Thu, 17 Nov 2011 17:46:39 +0000

Nephrotic syndrome (NS) is a state of hypercoagulability. In this paper, we sought to determine risk factors for the occurrence of deep vein thrombosis (DVT) in children with NS. The “with DVT” group included patients with decompensated NS and diagnosed with DVT. The “without DVT” group included the same patients, six to eighteen months prior to the episode of DVT, with decompensated NS but without DVT. Different prediction variables were analyzed. The odds ratio for the occurrence of DVT in patients with triglyceride levels ≥300 mg/dL was 3.14 (95% CI 1.14 to 8.64). For hematocrit levels ≥43% and for the presence of infection or a severe systemic event, the odds ratio was 4.37 (95% CI 1.23 to 15.53). The presence of significant risk factors for the occurrence of DVT in children with NS may serve as a warning for the occurrence of venous thrombosis.

Great Saphenous Vein Conventional Surgery in Brazil's Outpatients

Charles Angotti Furtado de Medeiros and Ana Terezinha Guillaumon — Thu, 17 Nov 2011 09:34:03 +0000

Objective. Evaluate great saphenous vein conventional surgery performed on an outpatient basis. Methods. Retrospective analysis where patients complain varicose veins with saphenofemoral incompetence and great saphenous vein reflux on Doppler ultrasound. These patients were consecutively enrolled to high ligation plus stripping, either to the ankle or only to the knee, or crossectomy alone. Results. Data from 106 surgery outpatients with CEAP clinical classification is as follows: varicose veins (59.5%), edema (15.1%), skin alterations (9.4%), healed ulcer (9.4%), or open ulcer (6.6%). The techniques employed were 66 high ligations plus stripping to the ankle, 28 high ligations plus stripping to the thigh portion, and 12 crossectomy. No major complications were observed. Overall, 18% reported symptoms consistent with saphenous nerve injury. All but one belonged to the stripping to the ankle group. Conclusion. Great saphenous vein conventional surgery performed on outpatients is very safe. Nerve injury is frequent when stripping extends the ankle.