M.A. Sharif

Endovenous laser treatment for long saphenous vein incompetence.

Endovenous laser treatment is a percutaneous technique used for the treatment of long saphenous vein (LSV) incompetence. This paper presents the results of an uncontrolled case series undertaken to assess the feasibility, safety and efficacy of this technique.

Risk factors for abdominal aortic aneurysm and the influence of social deprivation.

Introduction: the objective of this abdominal aortic aneurysm (AAA) screening study was to determine attendance and disease prevalence patterns in Northern Ireland and the role of deprivation and other risk factors. Patients and methods: patients from primary care practices from Belfast, Lisburn, and Saintfield were screened. Past medical history and deprivation details were determined. Results: 2264 men from Belfast, 1104 men in Lisburn, and 284 in Saintfield were invited to attend. Overall, 1659 (45.3%) men attended, with 40.6% from Belfast, 55.0% from Lisburn, and 45.8% from Saintfield (P < .0001). Ninety-two (5.5%) new AAAs were diagnosed, with 6.5%, 3.8%, and 6.2% in the 3 areas (P = .055). As deprivation decreased, attendance increased and prevalence decreased. Smoking, peripheral arterial disease, number of medications prescribed, and geographical origin were independent risk factors for AAAs. Conclusion: aneurysm prevalence is influenced by geographical origin and deprivation, which should, therefore, be important factors in health care planning and screening provision.

The Role of Smoking in Abdominal Aortic Aneurysm Development

Abdominal aortic aneurysm is common. The aim of this study was to assess the effect of smoking on prevalence and management. Patients attending the vascular unit and appropriate controls were prospectively recruited. A smoking history revealed tobacco exposure in pack years. Serum cotinine was assessed biochemically. Independent risk factors were statistically determined. In all, 202 (186 men) patients were recruited, with 202 (197 men) controls. A total of 69 patients tested positive for cotinine, whereas 39 controls were positive (P = .001). Smoking and ischemic heart disease were significant predictors for aneurysm prevalence. Cardiac disease emerged as a more important predictor than smoking in symptomatic patients. In noncardiac patients, smoking and hypercholesterolemia were significant risk factors. Smoking is a significant predictor for aneurysm development. In high-risk patients, the cardiac disease process is the most important factor, with control of this imperative. However, in noncardiac patients, smoking cessation and lipid-lowering therapy are crucial.

The Effects of Cilostazol on Exercise-induced Ischaemia-reperfusion Injury in Patients with Peripheral Arterial Disease

OBJECTIVES Cilostazol improves walking distance in peripheral arterial disease (PAD) patients. The study objectives were to assess the effects of cilostazol on walking distance, followed by the additional assessment of cilostazol on exercise-induced ischaemia-reperfusion injury in such patients. METHODS PAD patients were prospectively recruited to a double-blinded, placebo-controlled trial. Patients were randomised to receive either cilostazol 100mg or placebo twice a day. The primary end-point was an improvement in walking distance. Secondary end-points included the assessment of oxygen-derived free-radical generation, antioxidant consumption and other markers of the inflammatory cascade. Initial and absolute claudication distances (ICDs and ACDs, respectively) were measured on a treadmill. Inflammatory response was assessed before and 30 min post-exercise by measuring lipid hydroperoxide, ascorbate, alpha-tocopherol, beta-carotene, P-selectin, intracellular and vascular cell-adhesion molecules (I-CAM and V-CAM), thromboxane B(2) (TXB(2)), interleukin-6, interleukin-10, high-sensitive C-reactive protein (hsCRP), albumin-creatinine ratio (ACR) and urinary levels of p75TNF receptor. All tests were performed at baseline and 6 and 24 weeks. RESULTS One hundred and six PAD patients (of whom 73 were males) were recruited and successfully randomised from December 2004 to January 2006. Patients who received cilostazol demonstrated a more significant improvement in the mean percentage change from baseline in ACD (77.2% vs. 26.6% at 6 weeks, p=0.026 and 161.7% vs. 79.0% at 24 weeks, p=0.048) as compared to the placebo. Cilostazol reduced lipid hydroperoxide levels compared to a placebo-related increase before and after exercise (6 weeks: pre-exercise: -11.8% vs. +5.8%, p=0.003 and post-exercise: -12.3% vs. +13.9%, p=0.007 and 24 weeks: pre-exercise -15.5% vs. +12.0%, p=0.025 and post-exercise: -9.2% vs. +1.9%, p=0.028). beta-Carotene levels were significantly increased in the cilostazol group, compared to placebo, before exercise at 6 and 24 weeks (6 weeks: 34.5% vs. -7.4%, p=0.028; 24 weeks: 34.3% vs. 17.7%, p=0.048). Cilostazol also significantly reduced P-selectin, I-CAM and V-CAM levels at 24 weeks as compared to baseline (p<0.05). There was no difference between treatment groups for ascorbate, alpha-tocopherol, interleukin-6 and -10, hsCRP and p75TNF receptor levels. CONCLUSIONS Cilostazol significantly improves ACD, in addition to attenuating exercise-induced ischaemia-reperfusion injury, in PAD patients.

The effects of cilostazol on peripheral neuropathy in diabetic patients with peripheral arterial disease.

Background Evidence from diabetic animal models suggests that cilostazol, a cyclic AMP phosphodiesterase inhibitor used in the treatment of claudication, is efficacious in the treatment of peripheral neuropathy, although this is unproven in humans. The main aim of this study was to assess the effects of cilostazol on neuropathic symptomatology in diabetic patients with peripheral arterial disease (PAD). Methods Diabetic patients with PAD were prospectively recruited to a randomized double-blinded placebo-controlled trial. Baseline clinical data were recorded prior to trial commencement following medical optimization. Neurological assessment included the Toronto Clinical Neuropathy Scoring system (TCNS) and vibration perception thresholds (VPT) with a neurothesiometer at baseline, 6 weeks, and 24 weeks. Results Twenty-six patients were recruited from December 2004 to January 2006, which included 20 males. Baseline patient allocation to treatment arms was matched for age, sex, and medical comorbidities. There was no significant difference in neurological assessment between the treatment groups using the TCNS and VPT at 6 and 24 weeks. Conclusions Despite extensive animal-based evidence that cilostazol attenuates neuropathic symptomatology, our results do not support this effect in human diabetic PAD patients.

Smoking Impairs Endothelial Function in Human Saphenous Vein in an Ex Vivo Model

The aim of this ex vivo experimental study was to assess the effect of smoking, diabetes mellitus, and hypertension on endothelial function in human saphenous vein, a commonly used conduit for coronary and peripheral arterial bypass surgery. A segment of long saphenous vein harvested during infrainguinal bypass surgery was mounted in an organ bath for isometric tension studies. Vein rings were precontracted to submaximal contraction with phenylephrine, followed by endothelium-dependent relaxation with acetylcholine. Long saphenous vein segments were collected from 26 patients, including five females, with a mean age of 66.4 years (range 48-92). Current smokers had impaired endothelium-dependent relaxation compared to ex- and nonsmokers (10.2%, n=13, vs. 32.9%, n=13; p<0.010). However, ex-smokers and nonsmokers did not have a significant difference in relaxant responses to acetylcholine (29.1%, n=8, vs. 24.6%, n=5; p=nonsignificant [ns]). Similarly, diabetic and nondiabetic patients did not show a significant difference in endothelium-dependent relaxation (23.1%, n=10, vs. 15.6%, n=16; p=ns). The relaxant responses in hypertensive and normotensive patients were not different (20.4%, n=12, vs. 22.5%, n=14; p=ns). Smoking has a deleterious effect on the endothelial function of saphenous vein, and smoking cessation may improve the long-term durability of saphenous vein used as a bypass graft in patients undergoing arterial reconstruction.

Chlamydia pneumoniae Antibodies and C-Reactive Protein Levels in Patients with Abdominal Aortic Aneurysms

Introduction. The study aim was to assess the relationship between the presence of antibodies to Chlamydia pneumoniae and abdominal aortic aneurysm (AAA) incidence. Patients and Methods. Consecutive AAA patients and AAA-free controls were recruited prospectively. Serum samples from both groups were examined to determine Immunoglobulin (Ig) A and IgG titres against Chlamydia pneumoniae by ELISA and C-reactive protein (CRP) concentrations. Results were expressed as mean (SD) or median (IQR) and compared using χ 2 and Mann-Whitney U tests. A P value of <0.05 was considered statistically significant. Results. Each study group (AAA/nAAA) comprised 250 patients. 196 (78.7%) AAA patients had positive IgA antichlamydial antibody titres, compared to 181 (72.4%) in the control group (P = 0.008, OR 2.0, 95% CI 1.2–3.5). However, positive IgG antibody titres were similar (191 versus 203; P = 0.222, OR 0.7, 95% CI 0.4–1.3). Average CRP concentrations were higher in AAA individuals. IgA or IgG antibody titres were not related to CRP concentrations. Conclusions. These results demonstrated that the frequent incidence of Chlamydia pneumoniae antibodies within the general population makes it difficult to relate its presence to AAA development, despite the high IgA antibody titres. In addition, raised CRP concentrations in AAA patients are not related to the presence of antichlamydial antibodies.

Effects of antioxidants on endothelial function in human saphenous vein in an ex vivo model.

This ex vivo study is aimed at determining the beneficial effects of antioxidant agents on human saphenous vein endothelial function. Vein rings harvested during infrainguinal bypass surgery were assessed in an organ bath for endothelium-dependent relaxation, initially without and then with the addition of 10 μM manganese tetrakis benzoic acid porphyrin (MnTBAP), 0.01% N-acetylcysteine (NAC), 0.02% NAC, 10 μM vitamin C, and 100 μM vitamin C. Fifty-five vein rings from 22 patients were analyzed. MnTBAP improved the endothelium-dependent relaxation when compared with control (57.0% vs 37.8%, P < .01). Addition of 0.01% or 0.02% NAC did not improve the endothelium-dependent vasorelaxation (28.2% vs 18.6%, P = ns and 37.8% vs 29.8%, P = ns, respectively). Although 10-μM vitamin C failed to improve endothelial function (50.6% vs 37.2%, P = ns), 100-μM vitamin C significantly enhanced endothelium-dependent relaxation (66.5% vs 38.3%, P < .001). These results suggest that the addition of MnTBAP and high-dose vitamin C can improve the endothelial function of harvested saphenous vein segments in an ex vivo model.

The effects of N‐acetylcysteine on host inflammatory response and renal function in patients undergoing infra‐inguinal bypass surgery

forms at 50kDa. Protein application to human vascular endothelial cells leads to a specific phosphorylation of the Tie2 receptor, maximal at 1 μg/ml for each. Conclusion: Using rational design we have engineered the first small molecular mass ligands for the Tie2 receptor. Two of these ligands have been shown to activate the receptor. Studies are currently underway to test the functional effects of these novel ligands on vascular endothelial apoptosis, leakage and inflammation.