The Validity, Reliability, Reproducibility and Extended Utility of Ankle to Brachial Pressure Index in Current Vascular Surgical Practice

BACKGROUND

Despite the increasing sophistication of vascular surgical practice, more than three decades after its introduction to clinical practice, the ankle to brachial pressure index (ABPI) remains the cornerstone of non-invasive assessment of the patient with symptomatic peripheral arterial disease (PAD).

AIM

To summarise what is known about ABPI and critically appraise its validity, reliability, reproducibility and extended utility.

METHODS

A MEDLINE (1966-2004) and Cochrane library search for articles relating to measurement of ABPI was undertaken; see text for further details.

RESULTS

There is considerable disagreement as to how ABPI should be measured. Furthermore, various factors, including the type of equipment used, and the experience of the operator, can result in significant inter- and intra-observer error. As such, care must be taken when interpreting data in the literature. ABPI is valuable in the assessment of patients with atypical symptoms, venous leg ulcers and after vascular and endovascular interventions. However, absolute pressures are probably more valuable in patients with critical limb ischaemia. ABPI is also useful in subjects with asymptomatic PAD where it correlates well with, and may be used in screening studies to quantify, cardiovascular risk.

CONCLUSIONS

While its apparent simplicity can beguile the unwary, ABPI will continue to have a key role in the assessment of symptomatic PAD. ABPI is also likely to have extended utility in health screening and institution of best medical therapy in asymptomatic subjects.

Peri-operative Myocardial Injury in Patients Undergoing Surgery for Critical Limb Ischaemia

INTRODUCTION

Although up to a half of patients undergoing abdominal aortic aneurysm (AAA) repair suffer myocardial injury, as indicated by a rise in cardiac troponin I (cTnI), this is infrequently accompanied by a rise in creatine kinase (CK)-MB fraction or electrocardiogram (ECG) changes. This study compares for the first time peri-operative cTnI, CK-MB and ECG changes in patients undergoing surgery for critical lower limb ischaemia (CLI).

METHODS

Twenty-nine patients (20 men, median age 75 [range, 57-95] years) were studied prospectively. cTnI, CK/CK-MB ratio and ECG were performed pre-operatively and on post-operative days 1, 2 and 3.

RESULTS

Eleven (38%) patients had an elevated cTnI >0.5 ng/ml. Five (17%) patients had an elevated CK-MB fraction >4% and all of these patients had an elevated cTnI. Eleven (38%) patients had ischaemic changes on ECG including seven of 11 (64%) patients with elevated cTnI and all five patients with elevated CK-MB fraction. There was no relationship between pre-operative cardiac status, antiplatelet use or type of anaesthesia and post-operative cTnI rise. Patients with a cTnI rise were younger (p=0.01), and were more likely to have presented with gangrene (p=0.04) and have a longer operation time (p=0.01) than patients who did not demonstrate a cTnI rise. Four patients developed clinically apparent cardiac complications: cardio-pulmonary arrest (n=1), cardiogenic shock (n=1), acute CCF (n=1) and rapid atrial fibrillation (n=1). Survival at 6 months was 26 of 29 (90%) patients.

CONCLUSION

These data demonstrate that over a third of patients operated for CLI sustain peri-operative myocardial injury, many of which are not clinically apparent. Pre-operative medical optimisation may improve prognosis in this group of patients.

Assessment of smoking status in patients with peripheral arterial disease

OBJECTIVE

To assess the utility of a novel rapid urinary cotinine assay to detect and quantify the level of smoking in patients with peripheral arterial disease.

METHODS

This was a cross-sectional study in a vascular surgical outpatient department of a large teaching hospital. Participants were 100 consecutive subjects presenting to a hospital outpatient clinic with a diagnosis of intermittent claudication confirmed by a positive Edinburgh claudication questionnaire and an ankle-brachial pressure index of less than 0.9. Main outcome measures were patient-offered smoking history, exhaled breath carbon monoxide levels, urinary cotinine levels as measured by a novel rapid assay, and laboratory-measured creatinine-adjusted urinary cotinine levels. Results Fifty-five subjects declared that they were current smokers, 40 declared that they were ex-smokers, and 5 declared that they were never-smokers. Of the 40 ex-smokers, 6 subjects (15%) had urinary cotinine levels greater than 500 ng/mL (regular smokers), and a further 2 (5%) had urinary cotinine levels between 100 and 500 ng/mL (light, irregular, or passive smokers). The rapid urinary cotinine assay had a sensitivity and specificity of 100% and 98%, respectively, in its ability to detect active smoking, and the degree of smoking correlated well with laboratory creatinine-corrected urinary cotinine levels (Spearman coefficient, 0.805; P < .001). By contrast, exhaled carbon monoxide had a sensitivity and specificity of 95% and 89%, respectively, and although it correlated well with urinary cotinine (Spearman coefficient, 0.782; P < .001), it was found on linear regression analysis to be unreliable in differentiating light smokers from nonsmokers.

CONCLUSIONS

Patient-offered smoking history is unreliable because there is no correlation between the patient-reported number of cigarettes smoked per day and urinary cotinine levels. The novel rapid assay for urinary cotinine described here is superior to exhaled carbon monoxide measurement in detecting the level of smoking exposure among patients with intermittent claudication, and its results correlate well with laboratory-measured cotinine.

Manipulation of the Renin Angiotensin System in Peripheral Arterial Disease

The Heart Outcomes Prevention Evaluation (HOPE) study has provided evidence for the use of ramipril for secondary cardiac prevention for patients with peripheral arterial disease. Despite this many vascular surgeons and general practitioners are reluctant to prescribe ACE inhibitors in a group of patients perceived to have a high incidence of renal artery stenosis. This review aims to review the pathophysiology of the renin-angiotensin system and make evidence based recommendations for commencing ACE inhibitors as part of a comprehensive delivery of best medical therapy to patients with peripheral arterial disease.

The role of cilostazol in the treatment of intermittent claudication

This paper represents a review, by experts, of current opinion and information on intermittent claudication (IC) and the role that cilostazol plays in its treatment. IC is a common and debilitating condition that has a significant adverse impact on health-related quality of life (HR-QoL). It is currently under-recognised as a powerful marker of increased cardiovascular (CV) risk. The clinical priority is secondary prevention -- sometimes referred to as best medical therapy aimed at reducing CV risk. However, the priority for most patients (often overlooked by clinicians) is symptom relief: an increase in walking distance leading to an improvement in HR-QoL. The symptoms of IC may be improved by exercise, pharmacotherapy, and when these are unsuitable or unsuccessful, endovascular or surgical intervention. Cilostazol is indicated for the improvement of maximal and pain-free walking distance in patients with IC who do not have rest pain or tissue necrosis. In clinical trials, cilostazol improved symptoms both objectively and subjectively, and also improved HR-QoL. Cilostazol is usually well tolerated, with adverse events being generally mild to moderate in intensity, and transient or resolved after symptomatic treatment (e.g. non-prescription analgesics). Such events only infrequently require permanent drug withdrawal. There are no interactions with other drugs commonly prescribed in patients with IC, such as statins and anti-platelet agents. Cilostazol also has a range of potentially beneficial effects that may in the future be proven to decrease CV risk and modify the underlying process of atherosclerosis. Cilostazol represents the best evidence-based pharmacological therapy available for the symptoms of IC and should be the first-line treatment for symptom improvement in appropriate patients. Based on the available treatment strategies, the paper presents a suggested algorithm for the management of IC highlighting the role of cilostazol.

The effect of long saphenous vein stripping on deep venous reflux

BACKGROUND

The addition of long saphenous vein (LSV) stripping to sapheno-femoral junction (SFJ) disconnection and multiple stab avulsions (MSAs) in the course of varicose vein (VV) surgery is associated with a significant reduction in recurrence, and a significant improvement in quality of life. It is hypothesised that these benefits relate, at least in part, to a favourable effect of stripping on deep venous reflux.

OBJECTIVE

To examine the effect of long saphenous vein (LSV) stripping on deep venous reflux (DVR).

METHODS

This was prospective study of 62 consecutive patients (77 limbs) CEAP class 2-6, undergoing SFJ disconnection and MSAs, with and without successful stripping of the LSV to the knee. A duplex ultrasound examination was performed pre-operatively and at a median (IQR) of 24 (23-25) months post-operatively. Completely stripped limbs were defined as those in whom complete stripping of the LSV to the knee was confirmed on post-operative duplex. Reflux >/=0.5 s. was considered pathological.

RESULTS

Pre-operatively, 32 (42%) limbs had deep venous reflux (DVR). Post-operative duplex at 24 months revealed that the LSV had been completely stripped in 29 (38%) limbs. In patients with pre-operative DVR, complete stripping was associated with a significant reduction in the prevalence of superficial femoral vein (SFV) (p<0.001) and popliteal vein (PV) (p=0.016), McNemar test) on post-operative duplex. By contrast, in patients without pre-operative DVR, incomplete stripping was associated the development of SFV (p=0.031) and PV (p=0.008) reflux.

CONCLUSIONS

Complete LSV stripping abolishes DVR in a significant proportion of limbs, whereas failure to strip is frequently associated with the development of new DVR. These data support for routine stripping and suggest that the benefits of stripping may relate, at least in part, to a favourable impact on deep venous function.

ACE inhibitors increase type III collagen synthesis: a potential explanation for reduction in acute vascular events by ACE inhibitors

INTRODUCTION

Large trials have shown that angiotensin converting enzyme inhibitor (ACE-I) therapy reduces the risk of myocardial infarction and stroke. Acute vascular events are thought to be initiated by plaque rupture. Animal models of atherosclerosis show an increase in extra cellular matrix when given ACE-I therapy. ACE-I therapy could influence collagen synthesis, one of the major constituents of the atherosclerotic cap.

METHODS

A nested case-control study was performed within the Huntingdon Aneurysm Screening Project. Subjects were assessed for arterial disease, drug history and smoking. Blood samples were taken for a measure of collagen synthesis, the amino-terminal propeptide of type III procollagen (PIIINP), lipid levels, iron metabolism and cotinine levels.

RESULTS

Information was available for 420 subjects. Thirty-five were taking ACE-I therapy and 385 were not. Mean serum PIIINP level was 3.5 microg/l (sd 1.3 microg/l, range: 1.7-16.5 microg/l. There was a marked increase in mean collagen turnover between subjects taking ACE-I therapy compared to those not. Mean PIIINP level for cases and controls was 4.26 microg/l (95% CI: 3.73-4.79 microg/l) versus 3.61 microg/l (95% CI: 3.48-3.75 microg/l). No differences were found for patients taking other antihypertensive drugs. After adjusting for age, weight, height, lipid levels and ferritin, PIIINP levels remained significantly higher in cases than controls: 4.14 microg/l (95% CI: 3.72-4.57 microg/l) versus 3.62 microg/l (95% CI: 3.49-3.75 microg/l) (P-value 0.02).

DISCUSSION

These results suggest that ACE-I therapy up-regulates collagen synthesis, and could improve plaque stabilisation. This may provide an explanation for the decrease in acute vascular events observed in patients on ACE-I therapy.

Coagulopathy and Hyperfibrinolysis in Ruptured Abdominal Aortic Aneurysm Repair

Perioperative hemorrhage is one of the principal causes of death in patients with ruptured abdominal aortic aneurysm (AAA). This study examines perioperative coagulation and fibrinolysis in patients undergoing ruptured AAA repair complicated by coagulopathy. Eight patients (8 men of median age 74, range 69-87, years) who developed clinical and laboratory evidence of coagulopathy during attempted repair of ruptured infrarenal AAA were prospectively studied. Platelet count, fibrinogen, clotting times, prothrombin fragment (PF) 1+2, and tissue plasminogen activator (t-PA) and plasminogen activator inhibitor (PAI) activities were measured preoperatively, immediately before, and 5 min and 24 hr after aortic declamping. Six patients died, three intraoperatively, one within 24 hr, and two in the late postoperative period. All patients had thrombocytopenia and prolonged clotting times intraoperatively with evidence of increased thrombin generation (as demonstrated by elevated PF 1+2). Five patients had increased systemic fibrinolysis (as demonstrated by elevated t-PA activity) preoperatively and/or before aortic declamping and all of these patients died. Three patients had perioperative inhibition of systemic fibrinolysis (as demonstrated by elevated PAI activity) and two survived. These data demonstrate that coagulopathy in ruptured AAA repair may be associated with a hyperfibrinolytic state. Further research is required to determine if (a) a causal relationship exists between hyperfibrinolysis and coagulopathy and (b) whether antifibrinolytic agents can improve outcome if targeted at this group of patients.

The Effect of Superficial Venous Surgery on Generic Health-related Quality of Life

BACKGROUND

Superficial venous surgery (SVS) is associated with a significant improvement in disease-specific health related quality of life (HR-QoL) but the effect on generic HR-QoL remains uncertain. The aim of this study was to determine the effect of SVS on responses to the Short Form [SF]-36, the most widely used generic HR-QoL instrument.

METHOD

Two hundred and three patients undergoing SVS completed the SF-36 pre-operatively and 24 months post-operatively. Scores for the 8 SF-36 domains [physical (PF) and social functioning (SF), role limitation due to physical (RP) and emotional (RE) problems, mental health (MH), vitality (V), pain (P), and general health perception (HP)] were calculated and normalised using UK standard data.

RESULTS

Pre-operatively, patients scored significantly lower (worse) than the general UK population in PF, RP and P. Surgery was associated with a significant improvement in PF and P (45.3 vs. 42.5 and 48.9 vs. 43.8 postop vs. preop, p<0.001, WSR) at 2 years.

CONCLUSION

SVS leads to a statistically and clinically significant improvement in the physical components of the SF-36. These data will allow the clinical benefits of SVS to be compared with other interventions so helping informing decisions about how venous surgery should be prioritised appropriately within the NHS.

Dietary folate and vitamin b6 are independent predictors of peripheral arterial occlusive disease

BACKGROUND

It has been suggested that hyperhomocysteinemia (HHcy) is an independent risk factor for peripheral arterial occlusive disease (PAOD). However, the relationship between dietary folate and vitamin B6, cofactors in the metabolism of homocysteine (Hcy), and PAOD is unclear.

AIMS

To study the relationship between dietary folate and B6 and PAOD.

METHODS

Case-control population based study of 392 men older than 50 years living in Huntingdon, United Kingdom. PAOD, defined as an ankle-brachial pressure index (ABPI) < 0.9, was present in 86 (22%) of subjects. Folate, vitamin B6, and vitamin B12 intakes were calculated by means of the EPIC (European Prospective Investigation into Cancer) food frequency questionnaire.

RESULTS

Daily folate intake was significantly lower in case subjects (mean, 288; 95% confidence interval [CI], 266-309 microg) than in control subjects (324; 95% CI, 313-335 microg). Daily vitamin B6 intake was also lower in case subjects (2.05; 95% CI, 1.92-2.19 mg versus 2.26; 95% CI, 2.19-2.33 mg). Daily folate and vitamin B6 intakes were independent predictors of PAOD after adjusting for age, blood pressure, cholesterol levels, diabetes, and smoking status in a logistic regression model. This model suggests that increasing daily folate intake by 1 standard deviation decreased the risk of PAOD by 46%. A similar increase in daily vitamin B6 intake decreased the risk of PAOD by 29%.

CONCLUSION

In men older than 50 years, dietary folate and B6 intakes are independent predictors of PAOD. Longitudinal studies are required to determine whether dietary modification can reduce the incidence of PAOD in the population.

External Iliac Endofibrosis in Endurance Athletes: A Novel Case in an Endurance Runner and a Review of the Literature

BACKGROUND

There is increasing recognition that high-performance athletes can develop symptomatic arterial flow restriction in one or both (15%) legs due to kinking and/or endofibrosis of their iliac arteries.

METHODS

Case report and review based on a Medline search of the literature.

RESULTS

A 51-year-old female, 24-hour endurance runner presented with a six-month history of rapidly progressing intermittent claudication affecting her right thigh and calf in the absence of classical risk factors for atherosclerosis. On the basis of invasive and non-invasive investigations, a provisional diagnosis of endofibrosis was made and she was treated successfully with angioplasty.

CONCLUSIONS

The epidemiology, optimal investigation and treatment of iliac endofibrosis in endurance athletes is poorly described. Each individual unit's experience is likely to be very small. A European register of such cases would increase our understanding of the condition and improve patient outcomes.

LDL Cholesterol is Associated with Small Abdominal Aortic Aneurysms

OBJECTIVE

To examine the relationship between serum lipids and abdominal aortic aneurysms (AAA).

METHODS

Two hundred and six males (>50 years) with AAA (> or =30 mm) detected in a population based screening programme were compared with 252 age-matched male controls in a nested case-control study. Smoking status, previous medical and family histories, height, weight, blood pressure, ankle brachial pressure index (ABPI) and non-fasting lipid profile were recorded.

RESULTS

Cases were found to have significantly higher LDL cholesterol than controls. LDL cholesterol was an independent predictor of the risk for aneurysms in a logistic regression model adjusting for smoking status, family history of AAA, history of ischaemic heart disease, presence of peripheral vascular disease, use of lipid lowering medication and treatment for hypertension. There was a linear effect with increased levels of LDL cholesterol increasing the risk of having a small aneurysm (test for trend p=0.03).

CONCLUSION

The highly significant association between LDL cholesterol and small aneurysms suggests that LDL, possibly acting via inflammatory mediated matrix degeneration, could be an initiating factor in the development of AAA. The ability of statin therapy to prevent AAA formation requires further investigation.

The prevalence of hyperhomocysteinemia, methylene tetrahydrofolate reductase C677T mutation, and vitamin B12 and folate deficiency in patients with chronic venous insufficiency

INTRODUCTION

Hyperhomocysteinemia (HHcy) is a risk factor for venous thromboembolism, which in turn is a major cause of chronic venous insufficiency. HHcy may be more common in patients with chronic venous insufficiency, but the cause is unknown.

METHODS

One hundred hospital outpatients (52 women; median age, 66.5 years [interquartile range, 53-77 years] with venous disease C(2-6) underwent assessment of serum vitamin B(12) and folate concentration, plasma Hcy concentration, and C677T methylene tetrahydrofolate reductase (MTHR) homozygosity with polymerase chain reaction. HHcy was defined as greater than 15 micromol/L, the 95th centile of the normal range.

RESULTS

CEAP classification was C(2) in 39 patients, C(3) in 10 patients, C(4) in 13 patients, C(5) in 15 patients, and C(6) in 23 patients, with median Hcy concentration 11.6, 11.5, 12.5, 15.1, and 18.1 micromol/L, respectively (Kruskall-Wallis test, P <.001). Overall prevalence of HHcy was 39% (P <.001, binomial test vs normal population), and was significantly related (Pearson chi(2) for trend, 13.616; P <.009) to clinical grade: C(2), 23%; C(3), 20%; C(4), 39%; C(5), 53%; C(6), 65%. In a linear regression model, C(6) disease was a strong independent predictor (R(2) = 20.1%) for Hcy. Overall, 5 of 49 patients (10%, NS compared with normal population [5%]) with C(2-3) disease and 10 of 51 patients (20%) (P <.001, binomial test) with C(4-6) disease were homozygous for the C677T MTHFR polymorphism. Hcy levels and prevalence of HHcy were negatively correlated with vitamin B(12) levels (r = -0.248, P =.021, and r = -0.225;, P =.037, respectively). There was no significant relationship with folate. HHcy was present in 3 patients (all with C(5-6) disease) with either vitamin B(12) or folate deficiency, and in 8 of 15 patients homozygous for MTHFR C677T. No patient had HHcy, vitamin deficiency, and C677T mutation.

CONCLUSION

HHcy is common in patients with chronic venous insufficiency, especially those with ulceration. However, inasmuch as fewer than a third of patients with HHcy were C677T MTHFR homozygous or had vitamin B(12) or folate deficiency, other mechanisms must be responsible in the majority. Further work is required to determine the cause of HHcy in chronic venous insufficiency, whether HHcy is causally related to development and progression of the disease, and whether treatment would be beneficial.

von Willebrand Factor and Platelet Count in Ruptured Abdominal Aortic Aneurysm Repair

OBJECTIVE

von Willebrand factor (vWF) is essential for the formation of platelet aggregates at sites of vascular endothelial cell (EC) injury. Peri-operative thrombocytopenia is associated with poor outcome in ruptured abdominal aortic aneurysm (AAA) repair. This prospective study examines the relationship between vWF and platelet count (PC) in ruptured AAA repair.

METHODS

plasma vWF antigen, PC and C-reactive protein (CRP) were measured pre-operatively, and immediately before and 5 min after aortic clamp release, and on post-operative days 1 and 2 in 20 patients (18 men and 2 women of median age 74, range 63-86, years) with ruptured AAA.

RESULTS

elevated vWF was present in 13 (65%) patients pre-operatively, and 14 of 16 (88%) survivors at 24 h post-operatively. All patients demonstrated an intra-operative fall in vWF. There was no significant difference in vWF levels between survivors and non-survivors. PC was below the normal range in 8 (40%) patients pre-operatively and all patients at 24 h. Eighteen (90%) patients demonstrated an intro-operative fall in PC. PC was significantly lower in non-survivors pre-operatively (p=0.007), immediately before (p=0.009) and 5 min (p=0.009) and 24 h (p=0.02) after clamp release. There was a significant positive correlation between vWF and PC pre-operatively (r= +0.48, p=0.033), and immediately before (r= +0.47, p=0.044) and 5 min after clamp release (r= +0.5, p=0.043). There was a significant positive correlation between peak vWF level and the greatest fall in PC (r= +0.65, p=0.006). There was a significant negative correlation between vWF and CRP and operative blood loss; and between PC and CRP, operative blood loss and aortic clamp time.

CONCLUSIONS

these data demonstrate that EC activation, the acute phase protein response, operative blood loss and aortic clamp time all contribute to the peri-operative fall in PC in patients with ruptured AAA. The peri-operative fall in circulating levels of vWF and PC may represent consumption secondary to macro- and microvascular thrombus formation. The resultant procoagulant state may partly explain the association between low PC and poor outcome in ruptured AAA.

Smoking Cessation Strategies in Patients with Peripheral Arterial Disease: An Evidence-based Approach

INTRODUCTION

Smoking is the single most important aetiological factor for the development and progression of atherosclerosis. Unfortunately, most patients receive little or no treatment for their nicotine addiction. This review aims to make evidence based recommendations for smoking cessation as part of a comprehensive delivery of best medical therapy to patients with peripheral arterial disease.

METHODS

A search of MEDLINE (1966 to 2003) and the Cochrane library was undertaken for studies relating to smoking cessation. Major priority was given to meta-analyses of randomised controlled trials including Cochrane reviews.

RESULTS

Physician advise, nicotine replacement therapy and Bupropion are all evidence based treatments that have success in increasing the likelihood of permanent smoking cessation. A basic understanding of the psychology of addictive behaviour is essential so that appropriate advice and treatment can be tailored to individual patients.

CONCLUSIONS

Complete and permanent smoking cessation is by far the most clinically and cost effective intervention in patients with atherosclerosis. Greater awareness of smoking cessation strategies, by clinicians treating vascular patients, is essential for the effective delivery of best medical therapy.

Near patient cholesterol testing in patients with peripheral arterial disease

AIMS

To assess the bias, precision and utility of the Bioscanner 2000 for near patient testing of total cholesterol (NPTC) in patients with peripheral arterial disease (PAD).

METHODS

One hundred consecutive patients attending a hospital-based clinic with symptomatic PAD underwent non-fasting NPTC using finger prick blood sample and a laboratory total cholesterol (TC) using blood drawn from an antecubital fossa vein.

RESULTS

The Bioscanner 2000 showed good precision with a coefficient of variation of 1.8-3.8%. NPTC was significantly lower than laboratory TC (mean (S.D.) 4.67 (1.1) vs. 5.12 (1.2) mmol/l), p < or = 0.01, paired Student's t-test. Comparing the two methods using Deming regression revealed a 15% negative bias for the Bioscanner 2000 compared to laboratory testing, which was demonstrated to be a systematic bias using a Bland-Altman plot. Almost half (46%) of the readings differed by > 0.5 mmol/l, 16% by > 1.0 mmol/l and 3% by > 2 mmol/l. This means that if the cut-off for statin treatment were taken as a TC of 5.0 or 3.5 mmol/l then, based on NPTC, alone 18 and 6% of patients, respectively, would not have received a statin.

CONCLUSIONS

In the present study, NPTC significantly under-estimated TC when compared to laboratory testing. However, in the majority of cases, this would not have affected the decision to prescribe a statin and NPTC testing allows the immediate institution or titration of statin treatment.

The utilisation of superficial venous surgery for chronic venous insufficiency by the U.K. Asian population

BACKGROUND

The epidemiology of superficial venous disease is relatively well defined in the U.K. Caucasian population. By contrast, there are currently no data available for Asians, who comprise 3.6% of the U.K., and 14.1% of this institution's catchment population. The aim of this study was to compare surgery for superficial venous disease in Caucasians and Asians in this institution, in the context of our local population.

METHODS

A prospectively gathered database of all 2011 superficial venous operations performed between January 1997 and April 2002 was retrospectively analysed with regard to ethnicity. The ethnic, gender and age composition of our catchment area was determined from U.K. census data. The full institutional records of 100 Asian and 100 randomly selected age and sex-matched Caucasian patients were compared in a case control study.

RESULTS

After adjusting for age and gender according to census data, Asians were 40% less likely to undergo superficial venous surgery (SVS). Considering the 2011 operated patients as a whole, Asians were significantly younger and more likely to be male. In the case control study, Asians were significantly less likely to be operated for recurrent disease and significantly more likely to be operated for advanced disease.

CONCLUSIONS

Although Asians are significantly less likely to undergo SVS; those that do are more likely to be young, male and operated for skin changes and ulcers. This strongly suggests that the under-representation of Asians is due to cultural, genetic or environmental factors and unmet health care need, rather than a lower prevalence of clinically significant venous disease in the Asian population.

Exercise in claudicants is accompanied by excessive thrombin generation

BACKGROUND

exercise in IC leads to ischaemia-reperfusion injury of leg muscles and a systemic inflammatory response, but the effect of on coagulation is unknown.

OBJECTIVE

to compare the effect of exercise on thrombin formation and fibrin turnover in patients with IC (n = 10), and age and sex matched smokers ([S] n = 5) and non-smokers ([NS] n = 5) without peripheral vascular disease.

METHODS

blood was taken from subjects 60 and 30 min before, and 1, 5, 20, 40, 60 and 120 min after, treadmill exercise. Markers of thrombin generation (thrombin-antithrombin complexes [TAT] and prothrombin fragments 1 + 2 [PF1 + 2]) and fibrin turnover (D-dimer and fibrin degradation products [FbDP]) were assayed at each time point.

RESULTS

following exercise, thrombin generation was significantly greater in the claudicant group compared to the control groups (Area Under Curve [AUC] post exercise IC vs S vs NS; TAT 3960 vs 1623 vs 1476 vs = 0.007 Kruskal-Wallis [KW]; PF1 + 2 163 vs 107 vs 123 p = 0.024 KW). Pre and post-exercise, fibrin turnover in claudicants was similar to smoking controls, but higher than non-smoking controls. (AUC post exercise IC vs NS; D-dimer 6340 vs 2754 p = 0.055 Mann-Whitney U[MW]; FbDP 45113 vs 21511 p = 0.009 MW).

CONCLUSION

when compared to non-claudicants, exercise in IC is associated with excessive production of thrombin. Despite this, claudicants have a similar level of fibrin turnover suggesting a possible defect in fibrinolysis. This prothrombotic state may contribute to the excess thrombotic morbidity and mortality suffered by claudicants.

A comparison of patients who developed venous leg ulceration before and after their 50th birthday

BACKGROUND

although chronic venous ulceration (CVU) is often viewed primarily as a disease of the elderly, recent epidemiological data suggest that a significant proportion of patients first develop CVU before middle age. Such patients may represent a distinct group in terms of aetiology, natural history, prognosis and therapeutic options.

AIM

to compare patients who developed CVU before (Group 1) and after (Group 2) their 50th birthday.

METHODS

one hundred and eighteen consecutive patients with "pure" CVU underwent history and examination, measurement of ankle-brachial pressure index (ABPI) and duplex ultrasound examination of the affected limb. Pure venous ulcers were defined as those of >4 weeks duration in the presence of venous reflux (>0.5) and in association with an ankle: brachial pressure index of >0.8.

RESULTS

patients in Group 1 (n = 54, 46%) were more likely to be male (32/54 [59%] vs 14/64 [23%], p < 0.001 chi(2)), to have a higher median (interquartile [IQR]) body mass index (32 [27-39] vs 27 [23-34], p = 0.003, Mann-Whitney U [MWU]), to have a history of deep venous thrombosis (23/54 [43%] vs 16/64 [25%], p = 0.04 chi(2)) and of ipsilateral long bone fracture (13/54 [24%] vs 5/64 [8%], p = 0.01, chi(2)), to have previously undergone venous surgery (27/54 [50%] vs 19/64 [30%] a median (IQR) of 11.5 (6.5-19) and 10 (2-20) years earlier respectively, and to have worse disease in terms of the duration of present ulcer (12 (6-36) vs 8.5 [3-18] months, p = 0.035 MWU), the total duration of ulcer disease (216 [72-360] vs 48 [12-120] months, p < 0.001 MWU), and the number of episodes of ulceration (3 [2-7] vs 1 [1-3], p = 0.002 MWU). There was no significant difference between the two groups in the pattern and severity of venous reflux with 46/54 (85%) of Group 1 and 54/64 (84%) of Group 2 patients having surgically correctable superficial venous reflux.

CONCLUSION

patients who develop CVU before their 50th birthday appear to represent a distinct group in terms of aetiology, natural history and prognosis. The importance of thrombo-embolic prophylaxis in the prevention, and the detection and correction of superficial venous reflux in the treatment, of such ulcers is re-emphasised.

Ethnicity and peripheral arterial disease

INTRODUCTION

the prevalence of peripheral arterial disease (PAD) is relatively well defined for the Caucasian population. Given the susceptibility of Asians and Afro-Caribbeans to coronary heart disease and stroke respectively, and the high prevalence of cardiovascular risk factors in both groups, one would expect a high prevalence of peripheral arterial disease.

METHODS

a search of MEDLINE (1966-2002) was undertaken for studies on the incidence and prevalence of PAD, abdominal aortic aneurysms (AAA) and cerebrovascular disease in different ethnic groups.

RESULTS

there are very few population-based prevalence studies assessing PAD, AAA or cerebrovascular disease in non-Caucasians. A review of hospital-based series demonstrates different patterns of PAD between ethnic groups. Blacks and Asians have a tendency towards more distal occlusive disease and AAA appear to be predominantly a disease of Caucasians. It is not clear whether these studies provide a true representation of the prevalence of arterial disease in various ethnic groups or are the result of an unmet health care need.

CONCLUSIONS

further studies are required to establish the prevalence, natural history and response to treatment of PAD, AAA and cerebrovascular disease in non-Caucasians. Only when this has been achieved, can clinically and cost-effective health care be delivered to affected individuals from different ethnic groups.

The role of cilostazol (Pletal) in the management of intermittent claudication

Intermittent claudication affects 5% of the middle-aged population in developed countries and is associated with a significant reduction in health-related quality of life and cardiovascular morbidity and mortality. The mainstay of treatment is best medical therapy (BMT) comprising smoking cessation, antiplatelet agents, lipid-lowering, advice to exercise, and correction of other modifiable vascular risk factors. Although BMT is highly effective in reducing cardiovascular risk and may also improve walking distance, many patients remain unacceptably symptomatic despite it. Until recently, the only available adjuvant therapies were supervised exercise programmes, angioplasty and surgery. Many patients are unable to comply with the first, and the last two are associated with limited durability and risk. The advent of cilostazol (Pletal) adds evidence-based pharmacotherapy to the vascular specialist's armamentarium for the first time. Here cilostazol and its role in the management of intermittent claudication are discussed.