Amanda C Shepherd

Imperial College London, London, ENG, United Kingdom

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Publications (8)12.09 Total impact

  • Article: Pathogenesis and etiology of recurrent varicose veins.
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    ABSTRACT: BACKGROUND: Recurrent varicose veins (RVV) occur in 13% to 65% of patients following treatment, and remain a debilitating and costly problem. RVV were initially thought largely to be due to inadequate intervention, however, more recently neovascularization and other factors have been implicated. This review aims to provide an overview of the current understanding of the etiology and pathogenesis of RVV. METHODS: A systematic search of the PubMed database was performed using the search terms including "recurrent," "varicose veins," and "neovascularization." RESULTS: Three types of RVV have been reported, namely residual veins, true RVV, and new varicose veins, although the definitions varied between studies. RVV are attributable to causes including inadequate treatment, disease progression, and neovascularization. Using duplex ultrasonography, neovascularization has been observed in 25% to 94% of RVV. These new vessels appear in various size, number, and tortuosity, and they reconnect previously treated diseased veins to the lower limb venous circulation. Histologically, these vessels appear primitive with incomplete vein wall formation, decreased elastic component, and lack of valves and accompanying nerves. Although the rate of RVV following open surgery and endovenous treatment appears similar, neovascularization seems less common following endothermal ablation. Other causes of RVV following endovenous treatment include recanalization and opening of collaterals. CONCLUSIONS: Recurrence remains poorly understood following treatment of varicose veins. Neovascularization is an established and common cause of RVV, although other factors may contribute.
    Journal of vascular surgery: official publication, the Society for Vascular Surgery [and] International Society for Cardiovascular Surgery, North American Chapter 01/2013; · 3.52 Impact Factor
  • Article: Big Veins, Big Deal - Vein Diameter Affects Disease Severity, not Quality of Life
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    ABSTRACT: Journal of Vascular Surgery, 1 (2013) 101. doi:10.1016/j.jvsv.2012.10.008
    Journal of Vascular Surgery: Venous and Lymphatic Disorders. 12/2012; 1(1):101.
  • Article: The natural progression of chronic venous disorders: An overview of available information from longitudinal studies
    Amanda C Shepherd, Tristan R A Lane, Alun Huw Davies
    Phlebolymphology 01/2012; 19(3):138-147.
  • Article: Hypoxia-inducible factor-1 in arterial disease: a putative therapeutic target.
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    ABSTRACT: Hypoxia-inducible factor-1 (HIF-1) is a nuclear transcription factor that is upregulated in hypoxia and co-ordinates the adaptive response to hypoxia by driving the expression of over 100 genes. In facilitating tissues to adapt to hypoxia, HIF-1 may have a role in reducing the cellular damage induced by ischaemia, such as that seen in peripheral arterial disease (PAD), or following acute ischaemic insults such as stroke and myocardial infarction. This therefore raises the possibility of HIF-1 modulation in such contexts to reduce the consequences of ischaemic injury. HIF1 has further been implicated in the pathogenesis of atherosclerosis, abdominal aortic aneurysm (AAA) formation, pulmonary hypertension and systemic hypertension associated with obstructive sleep apnoea. Through a better understanding of the role of HIF-1 in these disease processes, novel treatments which target HIF-1 pathway may be considered. This review summarises the role of HIF-1 in arterial disease, specifically its role in atherosclerosis, ischaemic heart disease, in-stent restenosis following coronary revascularisation, stroke, PAD, AAA formation, pulmonary artery hypertension and systemic hypertension. The potential for exploiting the HIF-1 signalling pathway in developing therapeutics for these conditions is discussed, including progress made so far, with attention given to studies looking into the use of prolyl-hydroxylase inhibitors.
    Current Vascular Pharmacology 05/2011; 9(3):333-49. · 2.90 Impact Factor
  • Article: A study to compare disease-specific quality of life with clinical anatomical and hemodynamic assessments in patients with varicose veins.
    Amanda C Shepherd, Manj S Gohel, Chung S Lim, Alun H Davies
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    ABSTRACT: The wide variety of outcome measures to evaluate patients with varicose veins poses significant difficulties when comparing clinical trials. In addition, the relationship between different outcome measures is poorly understood. The aim of this study was to compare anatomical, hemodynamic, and clinical outcomes with disease-specific quality-of-life tools in patients undergoing treatment for varicose veins. Patients undergoing treatment for symptomatic veins in a single unit were studied. Assessments included duplex ultrasonography, digital photoplethysmography, evaluation of Venous Clinical Severity Scores and CEAP scores, generic (Short Form 12 [SF12]) and disease-specific (Aberdeen Varicose Vein Questionnaire [AVVQ], and Specific Quality-of-life and Outcome Response-Venous [SQOR-V]) questionnaires. Patients were reviewed at 6 weeks when hemodynamic, clinical, and quality-of-life assessments were repeated. The relationships between these outcomes were assessed. The AVVQ showed a strong positive correlation with the SQOR-V (Spearman coefficient 0.702; P < .001) and weaker, but significant correlations with the SF12 physical and mental component scores and the Venous Clinical Severity Score (VCSS) (P < .001, P = .019, and P < .001, respectively, Spearman correlation). No correlations were observed between the AVVQ and photoplethysmography results (Spearman coefficient -0.042; P = .606), and weak correlations were observed with the AVVQ and anatomical reflux. At 6 weeks, functional, clinical, and hemodynamic measurements were all responsive to changes following interventions; however, correlations observed between changes in disease-specific quality-of-life and generic, clinical, and hemodynamic outcomes were weak. Both the AVVQ and SQOR-V questionnaire are sensitive and responsive disease-specific questionnaires, which correlate with generic and clinical outcomes to some extent. Anatomical and hemodynamic measurements correlated poorly with functional outcomes both preoperatively and following interventions.
    Journal of vascular surgery: official publication, the Society for Vascular Surgery [and] International Society for Cardiovascular Surgery, North American Chapter 02/2011; 53(2):374-82. · 3.52 Impact Factor
  • Article: A study of patient satisfaction following endothermal ablation for varicose veins.
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    ABSTRACT: To evaluate patient satisfaction following endothermal ablation for varicose veins (VVs). A 12-question survey was sent to consecutive patients treated with endothermal ablation--questions related to preprocedure symptoms, recurrence, further treatments, and patient satisfaction. Questionnaires sent a median 12 (range 6-22) months postintervention were returned by 177 (60.0%) of 295 patients; 63 (35.6%) of 177 received treatment for recurrent VVs. Preintervention symptoms included aching (141 [79.7%] of 177), swelling (86 [48.6%] of 177), and heaviness (72 [40.7%] of 177). Improvements in preoperative symptoms were reported by 82.5% (146 of 177). Postintervention recurrence was reported by 87 (49.4%) of 177; 61 (70.1%) of 87 reported a few recurrent varicosities only. Further treatment was required by 11 (6.2%) of 177; 79 (44.6%) of 177 of patients reported no complications. The majority (151 [85.8%] of 176) were satisfied with their treatment. In all, 16 (25.4%) of 62 of patients treated for recurrent VVs were dissatisfied versus 9 (7.9%) of 114 of those with primary VVs (P = .0026). The majority of patients are satisfied with results following endothermal ablation. Dissatisfaction may be more likely following treatment for recurrent VVs.
    Vascular and Endovascular Surgery 03/2010; 44(4):274-8. · 0.99 Impact Factor
  • Article: Pain following 980-nm endovenous laser ablation and segmental radiofrequency ablation for varicose veins: a prospective observational study.
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    ABSTRACT: The aim of this study was to evaluate postoperative pain following endovenous laser ablation (EVLA) and radiofrequency ablation (RFA) and identify risk factors for increased pain. Patients undergoing either segmental RFA (VNUS Closure Fast, VNUS Medical Technologies, San Jose, California) or EVLA (980 nm) for varicose veins completed a preoperative disease-specific quality-of-life questionnaire (Aberdeen Varicose Vein Questionnaire [AVVQ]) and a diary card recording postoperative pain, return to normal activities, and return to work. Median 3- and 10-day pain scores were calculated. In all, 81 patients returned diary cards (RFA = 45, EVLA = 36). Patients receiving RFA reported less postoperative pain than those receiving EVLA at 3 days (14.5 vs 25.8 mm, P = .053, Mann-Whitney U test) and 10 days (13 vs 23.3 mm, P = .014, Mann-Whitney U test) and returned to work earlier than those receiving EVLA (median 5 vs 9 days, P = .022). Patients treated with segmental RFA had less postoperative pain and returned to work quicker than those treated with EVLA.
    Vascular and Endovascular Surgery 02/2010; 44(3):212-6. · 0.99 Impact Factor
  • Article: Peripheral arterial disease.
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    ABSTRACT: Peripheral arterial disease is commonly caused by atherosclerosis, and symptoms depend on the location and size of the affected artery, metabolic demands on the tissue, and the presence or absence of a collateral circulation. This article reviews the current evidence for the diagnosis and management of peripheral arterial disease.
    British journal of hospital medicine (London, England: 2005) 10/2009; 70(10):560-5. · 0.19 Impact Factor