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D A Legemate

Publications and source records attributed to D A Legemate.

At least 37 records · Page 2Linked to original sources

[Cannabis use and untreated HIV-infection: unknown risk factors for premature peripheral artery disease].

A 32-year-old woman presented with a painful leg and a gangrenous big toe. Her medical history included HIV-infection that had remained untreated for 8 years. In addition, she had smoked about 10 cannabis-cigarettes daily during the previous 15 years. Physical examination and angiography confirmed the presence of severe peripheral artery disease in the left lower leg. She received a femorodistal bypass graft but the gangrene was progressive, ultimately necessitating a lower leg amputation. Histopathological examination revealed intimal fibrosis and thrombosis with recanalisation in combination with fragmentation of the internal elastic membrane. Peripheral artery disease is often associated with lower extremity ischaemia, mostly affecting elderly patients and almost always caused by atherosclerosis. When ischaemic symptoms manifest themselves in young individuals (<40 years), rare causes of obliterative arterial disease, such as inflammation or post-traumatic vascular injury, must be excluded. Use of cannabis and untreated HIV infection are both relatively unknown risk factors for the onset of premature non-atherosclerotic arterial disease. Stopping the smoking of cannabis appears to have a favourable effect on the ischaemic symptoms. Whether treatment of HIV-infection can affect the course of premature peripheral vascular disease is unknown. When deciding whether or not to give antiviral therapy, care providers should also consider the increased cardiovascular mortality rates associated with these treatment regimens. In the case described, the HIV-infection was considered the most likely cause of the peripheral artery disease, based on all the histopathological findings.

Adult↗

[The practice guideline 'Peripheral vascular disease' (first revision) from the Dutch College of General Practitioners: a response from the perspective of surgery].

The practice guideline 'Peripheral vascular disease' is well written and based on evidence-based principles. In comparison with the previous guideline considerable attention is given to secondary prevention. In this guideline general practitioners are more diffident about prescribing statins than vascular specialists. This is probably related to the fact that this guideline refers to another guideline of the College concerning the treatment of patients with high-cholesterol concentrations and not to recently-published large studies. The guideline advises making a distinction between intermittent claudication stage 2a and 2b. This is impractical as the choice of therapy depends on the subjective feelings of disability. Some controversy remains with respect to the detection of asymptomatic abdominal aneurysms: should there routinely be only physical examination or ultrasonographic screening as well? The guideline advises against routine ultrasonic screening, which is in line with the view held by the author of this commentary.

Anticholesteremic Agents↗

Systematic review of survival after acute mesenteric ischaemia according to disease aetiology.

BACKGROUND: Differentiation of acute mesenteric ischaemia on the basis of aetiology is of great importance because of variation in disease progression, response to treatment and outcome. The aim of this study was to analyse the published data on survival following acute mesenteric ischaemia over the past four decades in relation to disease aetiology and mode of treatment. METHOD: A systematic review of the available literature from 1966 to 2002 was performed. RESULTS: Quantitative analysis of data derived from 45 observational studies containing 3692 patients with acute mesenteric ischaemia showed that the prognosis after acute mesenteric venous thrombosis is better than that following acute arterial mesenteric ischaemia; the prognosis after mesenteric arterial embolism is better than that after arterial thrombosis or non-occlusive ischaemia; the mortality rate following surgical treatment of arterial embolism and venous thrombosis (54.1 and 32.1 per cent respectively) is less than that after surgery for arterial thrombosis and non-occlusive ischaemia (77.4 and 72.7 per cent respectively); and the overall survival after acute mesenteric ischaemia has improved over the past four decades. CONCLUSION: There are large differences in prognosis after acute mesenteric ischaemia depending on aetiology. Surgical treatment of arterial embolism has improved outcome whereas the mortality rate following surgery for arterial thrombosis and non-occlusive ischaemia remains poor.

Acute Disease↗

Visceral and renal tissue oxygenation during supraceliac aortic crossclamping and left heart bypass with selective organ perfusion.

INTRODUCTION: Left-heart bypass (LHB) and selective organ perfusion (SOP) are used during thoracoabdominal aortic surgery to prevent ischemic damage to the kidneys and visceral organs after supraceliac aortic crossclamping. We studied the hypothesis, in a porcine model, that despite LHB and maximal SOP, visceral and renal ischemia still occurred during surgery. MATERIAL AND METHODS: Eleven pigs (54-70 kg) were coupled to a non-pulsatile LHB with inflow and outflow at the lower thoracic and distal infrarenal aorta, respectively. After supracoeliac and infrarenal aortic crossclamping, SOP was started using perfusion catheters. The proximal and distal mean aortic blood pressures were kept above 70 and 50 mmHg, respectively, while the mean blood pressure within the SOP system was above 60 mmHg. The visceral and renal tissue oxygenation was measured by intermittent blood gas analysis, from the portal and both renal veins. The jejunal mucosal oxygenation was measured by tonometric measurement of the luminal pCO2. RESULTS: Measured median blood blood flow through the LHB and the SOP system were 800 and 1140 ml/min, respectively. Median blood flow prior to, and during LHB and SOP through the celiac artery, superior mesenteric artery, and left renal artery were 300 and 240, 762 and 295, and 235 and 235 ml/min, respectively. During 3 h of LHB and SOP no significant changes in the renal tissue oxygenation were noted compared with the physiological situation prior to supracoeliac aortic crossclamping and cannulation. However, in the visceral vascular bed median mixed venous oxygen saturation dropped from 79 to 63% (p<0.001), and median oxygen extraction ratio increased from 26 to 41% (p<0.001). Median tonometric measured intraluminal jejunal pCO2 increased from 9.9 to 12.15 kPa (p>0.05). During 3 h of LHB and SOP no hemolysis was detected, as there was no rise in serum LDH. CONCLUSION: LHB and SOP preserves renal but not visceral tissue oxygenation during supraceliac aortic crossclamping and does not induce hemolysis.

Animals↗

Angioplasty or bypass for superficial femoral artery disease? A randomised controlled trial.

AIM: To evaluate whether angioplasty or above-knee bypass is the best treatment for symptomatic superficial femoral artery occlusive lesions, we performed a multicentre randomised trial. PATIENTS AND METHODS: Between October 1995 and August 1998, 56 patients were enrolled, all with symptoms related to a 5-15 cm long occlusive lesion of the superficial femoral artery. Thirty-one patients were randomly assigned to percutaneous transluminal angioplasty (PTA); 25 patients to bypass surgery. All patients were followed at 1, 6 and 12 months after the procedure. The primary outcome of our study was re-occlusion of the femoral artery. RESULTS: Thirty patients underwent the allocated PTA and 24 patients underwent bypass surgery. Cumulative 1-year primary patency after PTA was 43 and 82% after bypass surgery. After PTA more than half of the patients had a re-occlusion with an absolute risk reduction of 31% (CI: 6-56%) in favour of bypass surgery. The hazard ratio for occlusion comparing PTA with bypass surgery is 2.24 (95% CI: 0.9-5.58). CONCLUSION: Despite 18 participating centres only 56 patients were randomised to PTA our bypass surgery. Based on our results, for every three patients treated with bypass surgery instead of PTA, one additional re-occlusion is prevented. Therefore, we conclude that with respect to patency, for long superficial femoral artery (SFA) stenoses or occlusions, surgery is better than PTA.

Adult↗

Early post-operative glucose levels are an independent risk factor for infection after peripheral vascular surgery. A retrospective study.

OBJECTIVE: To evaluate whether hyperglycaemia in the first 48 h after infrainguinal vascular surgery is a risk factor for post-operative infection, independent from factors associated with insulin resistance and surgical stress. DESIGN: Retrospective cohort study. PATIENTS AND METHODS: Patients who underwent infrainguinal vascular surgery in our hospital between March 1998 and March 2003 were included. Glucose values until 48 h after surgery were retrieved from laboratory reports. Post-operative infections, treated with antibiotics, during hospital stay were scored until 30 days after surgery. Data were analysed with univariate and multivariate logistic regression analyses. RESULTS: At least one post-operative glucose value was retrieved for 211/275 (77%) patients. The incidence of post-operative infections was 84/275 (31%). When corrected for factors associated with insulin resistance and surgical stress, post-operative glucose levels were found to be an independent risk factor for post-operative infections (odds ratio top quartile versus lowest quartile: 5.1; 95% confidence interval: 1.6-17.1; P=0.007). CONCLUSION: Post-operative glucose levels appear to be an independent risk factor for infections after infrainguinal vascular surgery. This finding requires confirmation in a prospective study.

Aged↗

Morphological and functional alterations in glycerol preserved rat aortic allografts.

Glycerol preservation is an effective method for long-term preservation of skin allografts and has a potential use in preserving arterial allografts. We evaluated the effect of glycerol concentration and incubation period on vessel-wall integrity of rat aortic allografts. No significant differences were measured in breaking strength (2.3 +/- 0.3 N) and bursting pressure (223 +/- 32 kPa) between standard glycerolized and control segments (1.7 +/- 0.3 N, 226 +/- 17 kPa). Isometric tension measurements showed complete lack of functional contraction and relaxation capacity in allograft segments prepared according to all preservation protocols. Morphologically, thickness of the vessel-wall media diminished after preservation using low (30/50/75%) or high (70/85/98%) concentrations of glycerol, as compared to control segments (i.e. 81 +/- 2.4 microm, 95 +/- 5.6 microm and 125 +/- 3.5 microm, respectively). Confocal microscopy and Fourier analysis demonstrated that vascular collagen and elastin bundle orientation had remained unaltered. Electron microscopy showed defragmentation of luminal endothelial cells. In conclusion, glycerol preservation of rat aorta resulted in an acellular tissue matrix, which maintained biomechanical integrity and extracellular matrix characteristics. The next step in the investigation will be to test the concept of glycerol preservation of arterial allografts in a vascular transplantation model.

Animals↗

Smoking cessation interventions in cardiovascular patients.

OBJECTIVES: To review current evidence for the effectiveness of smoking cessation interventions in cardiovascular patient populations. DESIGN AND MATERIALS: Studies were obtained from systematic reviews of the Cochrane Tobacco Addiction Review Group. Twelve Cochrane reviews related to secondary prevention in a variety of populations were used to extract eligible studies. Studies were eligible when they considered smokers diagnosed with symptomatic cardiovascular disease. METHODS: Data concerning the comparison between the intervention of interest and a placebo or standard treatment group were derived from eligible papers. Based on these data, Absolute Risk Reduction figures were calculated to express the effectiveness of each intervention on smoking cessation. RESULTS: We found 12 studies examining smoking cessation interventions in cardiovascular patients. Five studies reported significant results. No evidence was found for Nicotine Replacement Therapy or other pharmacology to be effective, neither for self-help materials, group, individual or telephone counseling. There is limited evidence for physician's advice and nurse-delivered interventions to be effective. CONCLUSIONS: Smoking cessation studies in cardiovascular patients are scarce. The available studies show very limited effects. The reasons for the lack of success of smoking cessation strategies in these patients remain unclear. Further research is needed to find effective cessation strategies for patients with cardiovascular diseases.

Behavior Therapy↗

Interobserver variation in duplex scanning of infrainguinal arterial bypass grafts.

OBJECTIVE: to determine the degree of interobserver variation of color-flow duplex scanning of infrainguinal arterial bypass grafts. METHODS: two experienced vascular technologists randomly assessed bypass grafts in 32 consecutive patients, using a color-flow duplex scan. In pre-defined segments the highest peak systolic velocity (PSV(max)) and end-diastolic velocity (EDV) were measured and a peak systolic velocity ratio (PSV ratio) was calculated. Results were analyzed as continuous variables (Bland and Altman plots and Intraclass Correlation Coefficient=ICC) and also as categorical data (weighted Kappa coefficient) for the PSV ratio 1-2.5, > or =2.5-4, > or =4.0. RESULTS: the ICC for the PSV(max), PSV ratio and EDV indicated "almost perfect" agreement for all three parameters. However, the Bland and Altman plots showed impressive interobserver variation for the higher values of all three parameters. For the PSV ratio categories a weighted kappa of 0.31 was calculated, indicating only fair agreement. Substantial variation was found for the categories with PSV ratios > or =2.5-4.0 and > or =4.0. CONCLUSION: though performing accurately for the lower values of the assessed parameters, duplex scanning shows considerable interobserver variation for the clinically significant higher values. Particularly in the PSV ratio interval > or =2.5-4.0, most relevant for clinical decision-making, the interobserver variability is unacceptable.

Aged↗

Absent collateral function of the circle of Willis as risk factor for ischemic stroke.

BACKGROUND: Autopsy studies show a higher prevalence of circle of Willis anomalies in brains with signs of ischemic infarction. Our goal was to examine the collateral function of the circle of Willis in ischemic stroke patients and to assess in a case-control study if a collateral deficient circle of Willis is a risk factor for ischemic stroke in patients with severe internal carotid artery (ICA) occlusive disease. METHODS: Our case-control study included 109 patients with an acute ischemic stroke in the anterior circulation and 113 patients with peripheral arterial disease and no known history of cerebral ischemia. The collateral function of the anterior and posterior communicating arteries of the circle of Willis was assessed by means of transcranial color-coded duplex ultrasonography (TCCD) and carotid compression tests. RESULTS: TCCD was successfully performed in 75 case patients (mean age 64 years, range 41-91 years) and in 100 control patients (mean age 61 years, range 35-89 years). In 26 cases and 19 controls, a >/=70% stenosis or occlusion of the ICA was found. A nonfunctional anterior collateral pathway in the circle of Willis was found in 33% of the cases and in 6% of the controls (p < 0.001). The posterior collateral pathway was nonfunctional in 57% of the cases and in 43% of the controls (p = 0.02). In patients with severe ICA occlusive disease, the odds ratios of a nonfunctional anterior and a nonfunctional posterior collateral pathway were 7.33 (95% confidence interval, CI, = 1.19-76.52) and 3.00 (95% CI = 0.77-12.04), respectively. CONCLUSIONS: Patients who suffer ischemic stroke in the anterior circulation have a higher incidence of collateral deficient circles of Willis than those with atherosclerotic vascular disease without ischemic cerebrovascular disease. The presence of a nonfunctional anterior collateral pathway in the circle of Willis in patients with severe ICA occlusive disease is strongly associated with ischemic stroke.

Adult↗

[Physical diagnostics--peripheral arterial diseases].

In a patient with a high a priori risk of peripheral vascular disease, the positive predictive value of an abnormal physical diagnostic examination is high. In patients with a low prior probability of peripheral vascular disease, the physical examination makes little contribution to the diagnosis or exclusion of arterial insufficiency. For this purpose the ankle-brachial systolic pressure index is preferable. Peripheral arterial disease is unlikely when this index is normal. However, a low ankle-brachial index necessitates further investigations to determine possible arterial insufficiency in the lower extremities.

Ankle↗

Magnetic resonance angiography for the evaluation of lower extremity arterial disease: a meta-analysis.

CONTEXT: Magnetic resonance angiography (MRA) is a rapidly evolving technique that has been reported to be accurate for assessment of lower extremity arterial disease. OBJECTIVE: To obtain the best available estimates of the diagnostic performance of MRA in patients with lower extremity arterial disease. DATA SOURCES: Studies published from January 1985 through May 2000 in English, German, or French, identified from the MEDLINE, EMBASE, and Current Contents databases. STUDY SELECTION: Studies were included that allowed construction of 2 x 2 contingency tables for detection of stenosis greater than 50% or occlusion with MRA or arteriography in patients with claudication or critical ischemia. DATA EXTRACTION: Two observers graded the following elements of study quality: consecutively enrolled patients, prospective study design, clear cut-off levels, blinded assessment, and clear description of MRA technique. Summary receiver operating characteristic analysis was performed to examine the influence of year of publication, all methodological criteria, arterial tract, number of subdivisions within arterial tracts, and MRA technique on diagnostic performance. DATA SYNTHESIS: Of 3583 studies initially identified, 34 were included that evaluated MRA in 1090 patients (72% men; median age, 65 years). Magnetic resonance angiography was highly accurate for assessment of all lower extremity arteries. Three-dimensional gadolinium-enhanced (3-D Gd) MRA improved diagnostic performance compared with 2-D MRA (relative diagnostic odds ratio, 2.8 [95% confidence interval, 1.2-6.4]), adjusted for number of subdivisions within arterial tracts. The estimated points of equal sensitivity and specificity were 94% and 90% for 3-D Gd MRA and 2-D MRA, respectively. CONCLUSIONS: Magnetic resonance angiography is highly accurate for assessment of the entire lower extremity for arterial disease. Three-dimensional Gd-enhanced MRA improves diagnostic performance compared with 2-D MRA.

Aged↗

Interobserver variation of colour duplex scanning of the popliteal,tibial and pedal arteries.

OBJECTIVES: to determine interobserver variation in the measurement of Peak Systolic Velocity (PSV) and grading of disease by means of Duplex scanning (DS) in the popliteal, tibial and pedal arteries. DESIGN: prospective validation study. MATERIALS: twenty-four consecutive patients with severe claudication (n=6), ischaemic rest pain (n=11) and tissue loss (n=7). METHODS: two vascular technologists independently examined the popliteal, tibial and pedal arteries. The PSV was recorded in 15 arterial segments that were graded with B-mode and Doppler parameters as fully patent, severely diseased or occluded. Concordance in PSV recordings was expressed as intraclass correlation coefficients (ICC). Agreement in artery assessment was expressed as weighted kappa-values. RESULTS: the ICC for PSV measurements was 0.90 (95% CI, 0.86 to 0.93) within the popliteal and tibial arteries and 0.64 (95% CI, 0.37 to 0.81) within the pedal arteries. Agreement for grading disease was good within the popliteal and tibial arteries (kappa 0.66, 95% CI, 0.58 to 0.74), and moderate within the pedal arteries (kappa 0.54, 95% CI 0.33 to 0.74). The presence of diabetes or stage of disease did not influence interobserver agreement. CONCLUSION: interobserver agreement of DS is good within the popliteal and tibial arteries and moderate within the pedal arteries.

Aged↗

Interobserver variation in interpretation of arteriography and management of severe lower leg arterial disease.

OBJECTIVE: arteriography is the reference standard for the assessment of the lower leg arteries in patients with severe lower limb ischaemia. Interobserver variation in arteriography interpretation may cause disparities with non-invasive imaging modalities. We determined interobserver variation in lower leg artery assessment with intra-arterial digital subtraction angiography (IaDSA) and subsequent patient management. MATERIALS: iaDSA studies of patients evaluated for severe claudication (n =5) or critical ischaemia ( n =43). METHODS: arteriograms were independently judged by four observers. The popliteal and tibial arteries were graded as fully patent, severely diseased, occluded or non-diagnostic. The dorsalis pedis, common and deep plantar artery were graded as directly, indirectly or not filling the pedal arch or non-diagnostic. Agreement on grading arteries was expressed as kappa-values. Treatment plans (conservative, PTA, surgery, amputation, non-diagnostic) proposed by each observer based on clinical information and iaDSA were compared. RESULTS: the rate of non-diagnostic judgements ranged from 1% in the popliteal to 22% in the pedal arteries. Overall agreement was good for grading the popliteal arteries (kappa=0.64), moderate for the tibial (kappa=0.47--0.54) and fair for the pedal arteries (kappa=0.39). Agreement was good to excellent for grading occluded or fully patent popliteal and tibial artery segments, and fair to moderate for grading severe disease. In 57% of cases at least 3 observers proposed identical treatment, which indicates fair overall agreement (kappa=0.33). CONCLUSION: interobserver agreement on iaDSA is good to determine occluded or fully patent popliteal or tibial arteries, but not for severe disease. This should be taken into account when other diagnostic modalities are compared with iaDSA. Evaluation of diagnostic modalities as concordance in treatment plans is flawed by interindividual variation.

Adult↗

The value of the peak systolic velocity ratio in the assessment of the haemodynamic significance of subcritical iliac artery stenoses.

OBJECTIVES: iliac stenoses with a PSV ratio between 2.0 and 3.0 in patients with symptomatic arterial obstructive disease of the legs might be misinterpreted when compared with intra-arterial pressure measurements (IAPM). The aim of this study was to compare the value of the PSV ratio with IAPM as the reference standard in the assessment of the haemodynamic significance of subcritical iliac artery stenoses (iliac stenosis with PSV ratio between 1.5 and 3.5). DESIGN, PATIENTS AND METHODS: fifty-eight iliac tracts in 53 consecutive patients with symptomatic arterial obstructive disease of the legs with an isolated stenosis with PSV ratio between 1.5 and 3.5 were studied prospectively. The results of those iliac duplex scanning were compared to IAPM. Results a poor agreement was found between IAPM and PSV ratios. For the PSV ratios > or =2.0, 2.5 and 3.0 the sensitivities were 74%, 37% and 16%, respectively. The specificities were 70%, 90% and 95%, the positive predictive values 82%, 88% and 86%, respectively, and the negative predictive values 58%, 43% and 37%, respectively. CONCLUSION: the results of this study show that the PSV ratio parameter is not accurate enough to evaluate the haemodynamic significance of subcritical iliac artery stenoses.

Adult↗

Interobserver and intraobserver reproducibility of peripheral blood and oxygen pressure measurements in the assessment of lower extremity arterial disease.

INTRODUCTION: Peripheral blood pressure measurements play a prominent role in the diagnosis and follow-up of patients with peripheral vascular diseases. Toe pressure of the hallux (TP1) and second toe (TP2) and transcutaneous oxygen pressure (TCPO2) measurements are becoming more important. The ankle/brachial pressure index (ABPI) is known to be a reliable parameter, but the toe pressure and TCPO2 are evaluated less thoroughly. Therefore, we evaluated the reproducibility of TP1, TP2, TCPO2, ABPI, ankle pressure (AP), and brachial pressure (BP). PATIENTS AND METHODS: In 54 patients with various stages of peripheral vascular disease, the intraobserver and interobserver reproducibility of BP, AP, ABPI, TP1, TP2, and TCPO2 was investigated by calculating the repeatability coefficient (RC) and the intraclass correlation coefficient (ICC) and by using Bland-Altman plots. RESULTS: The intraobserver and interobserver reproducibility at 1 day and after 1 week of BP, AP, ABPI, and TP1 was substantial and comparable (ICC range, 0.80-0.99), except for the BP after 1 week. The TP2 and TCPO2 were less reproducible (ICC range, 0.62-0.98). The interobserver RC of BP was 31 mm Hg; of AP, 44 mm Hg; of ABPI, 27%; of TP1, 41 mm Hg; of TP2, 67 mm Hg; and of TCPO2; 30 mm Hg. The difference plot showed that the observer variability was equally distributed across the range of pressure in all measurements. CONCLUSION: The BP, AP, ABPI, and TP1 have a substantial intraobserver and interobserver reproducibility, whereas TP2 and TCPO2 show worse reproducibility. Especially when low values (or values around a cutoff value) are measured, the RC should be taken into account, and repetition of the measurement is advocated.

Aged↗