Mutation analysis of the aggrecan gene in chickens with tibial dyschondroplasia.

Expression studies suggest that the incidence and severity of tibial dyschondroplasia (TD) in chickens, Gallus gallus, may be affected by the aggrecan gene, AGC 1. Here, results are described of a scan for single nucleotide polymorphisms (SNP) in AGC1 in genetic lines divergently selected for TD incidence in chickens. A total of 3,048 bp of DNA sequence obtained from amplicons produced by 4 primer-pairs designed from the GenBank AGC1 cDNA sequence were scanned for SNP. Among the 18 SNP detected and validated, only 2 were nonsynonymous. Allelic frequency differences between TD-affected and nonaffected birds were not statistically significant for all the SNP. The current results do not support an association of Gallus gallus AGC1 variation at the DNA level with the incidence of TD in chickens. The genomic resources described, however, including the SNP, could be useful in further evaluating AGC1 in other populations for association with TD or other skeletal abnormalities.

Effect of chronic renal failure on mortality rate following arterial reconstruction.

BACKGROUND: There is some evidence that patients with renal failure who have arterial procedures may have a poor outcome. This study compared the hospital mortality rate of arterial surgery in patients with chronic renal failure and those with normal renal function. METHODS: A consecutive series of 1718 patients undergoing arterial reconstructive surgery (excluding amputation) was entered prospectively on to a computerized database. Chronic renal failure was defined as a serum creatinine level over 400 micromol/l, or dialysis (either peritoneal or haemodialysis), or a successful renal transplant. Mortality was assessed at 30 days or in hospital. RESULTS: There were 69 patients (4.0 per cent) who were defined as having chronic renal failure. The mortality rate in this group was 23 per cent (16 patients) compared with 7.3 per cent (120 patients) of the 1649 patients without renal failure. The mortality rate was highest in patients undergoing urgent or emergency surgery and in those undergoing reconstruction for lower limb occlusive disease. The main causes of death were related to the cardiovascular system. CONCLUSION: Patients with chronic renal failure undergoing arterial surgery have a poor outcome compared with those with normal renal function.

Effect of contralateral disease on duplex measurements of internal carotid artery stenosis.

BACKGROUND: Duplex ultrasonography is increasingly used as the sole method of imaging before carotid endarterectomy. This study investigated the measured degree of stenosis in the contralateral carotid artery before and after operation. METHODS: Duplex-derived peak systolic velocity (PSV), end-diastolic velocity (EDV) and internal carotid artery/common carotid artery (ICA/CCA) velocity ratios were measured in the contralateral unoperated ICA before 131 consecutive unilateral endarterectomies and compared with preoperative angiographic findings. Three months later duplex scans were repeated to assess whether there had been any alteration in the severity of the stenosis in the contralateral unoperated artery. RESULTS: Bilateral ICA disease (greater than 50 per cent stenosis) was present in 50 patients (38 per cent). Three months after operation, ultrasonography of the 105 unoperated, patent, contralateral arteries showed a decrease in mean(s.d.) PSV (1.21(0. 83) versus 1.07(0.69) m/s; P < 0.01) and EDV (0.41(0.29) versus 0. 35(0.24) m/s; P < 0.01). This resulted in 14 (42 per cent) of 33 patients with contralateral disease being downgraded to a less severe category of stenosis. Use of the ICA/CCA velocity ratio prevented overestimation in eight of the 14 patients, while preoperative angiography correctly classified 13 of the 14 patients. CONCLUSION: Bilateral carotid artery disease can cause overestimation of the severity of stenosis by duplex ultrasonography if absolute velocity is used as the main criterion.

Fogarty balloon dilatation for intraoperative arterial spasm.

OBJECTIVE: to describe an intraoperative technique using a Fogarty balloon to treat arterial spasm following vascular bypass and endarterectomy. DESIGN: prospective case control study. SUBJECTS AND TREATMENT: twenty-two patients following femorodistal bypass surgery and one patient following carotid endarterectomy, with arterial spasm in the distal run-off on completion angiography, were treated with Fogarty balloon dilatation. MATERIALS: Fogarty balloon catheter (Baxtertrade mark). RESULTS: twenty-three patients (100%) with arterial spasm were successfully treated by Fogarty balloon as demonstrated on completion angiography. No complications were seen. CONCLUSION: this simple technique removes vascular spasm rapidly and produces an excellent angiographic result.

Endoleaks following conventional open abdominal aortic aneurysm repair.

OBJECTIVE: to describe the complication of <<<>>> following conventional open abdominal aortic aneurysm (AAA) repair. DESIGN: prospective case study. SETTING: two specialist vascular surgical centres. PATIENTS AND METHODS: six patients who had successful conventional open AAA repair. RESULTS: six patients presented with back or abdominal pain or hypotension between one and eighteen months later. An endoleak at the distal anastomosis was noted in five of the cases and one endoleak at the proximal anastomosis. All six cases were successfully repaired; two of these patients required Dacron graft replacement, whilst in four cases only direct resuturing was needed. There was no evidence of infection. CONCLUSIONS: an endoleak is not a phenomenon confined to stent grafts. It should be considered in all patients who present with back or abdominal pain within eighteen months of open AAA repair. The combination of computed tomography (CT) scan and digital subtraction angiography is most useful for preoperative diagnosis.

The association between laser Doppler reactive hyperaemia curves and the distribution of peripheral arterial disease.

OBJECTIVES: To determine whether postocclusive laser Doppler fluxmetry (LDF) curves can be related to the arteriographic distribution of disease. DESIGN: Prospective study. MATERIALS: Sixty-nine patients with symptomatic peripheral ischaemia and 15 healthy subjects. METHODS: Laser Doppler fluxmetry (LDF) was monitored on the dorsum of the symptomatic foot following 2 min of arterial occlusion at the ankle. During reperfusion three patterns of LDF were identified (types I-III). All patients subsequently underwent arteriography which was reported independent of LDF results. The distribution of disease, particularly patency of below-knee vessels, was related to the type of LDF curve observed during reactive hyperaemia. RESULTS: Type I curves were observed in all healthy subjects and 75% of patients with a single arterial lesion. Type II curves were found in 78% of patients with multiple lesions above the knee. The presence of either a type I or II curve was associated with a continuous vessel from knee to ankle (positive predictive value 83%, p < 0.01), whilst type III curve was associated with discontinuous infrapopliteal run-off (positive predictive value 86%, p < 0.01). CONCLUSIONS: This pilot study suggests that post-occlusive LDF curves may identify the distribution of arterial disease and may be useful in the non-invasive management of peripheral ischaemia.

A review of alternative approaches in the management of iatrogenic femoral pseudoaneurysms.

The management of iatrogenic pseudoaneurysms (IPAs) demands close co-operation between radiologist, vascular surgeon and plastic surgeon. Ideally, each patient should be reviewed employing a team approach. Many IPAs require only observation; those with a volume greater than 6 cm3 will require treatment as spontaneous thrombosis is uncommon. Radiological treatment options include ultrasound guided compression repair (UGCR), embolisation, and covered stenting. Occasionally, these are unsuccessful or contra-indicated, and the vascular surgical approach is discussed in detail. Finally, the role of the plastic surgeon in dealing with skin ischaemia is detailed.

The relationship between the delayed improvement in ankle-brachial pressure index and changes in limb volume following balloon angioplasty for leg ischaemia.

OBJECTIVES: To investigate the association between changes in the ankle-brachial pressure index (ABPI) and simultaneous changes in calf volume following percutaneous transluminal angioplasty (PTA) for chronic leg ischaemia. MATERIALS: A total of 37 consecutive patients undergoing PTA for chronic leg ischaemia. METHODS: Bilateral calf volume, as calculated from girth measurements, and ABPI were determined before PTA, and repeated 24 h and 1 week following the procedure. Changes in the calf volume of the treated leg, both absolute and relative to changes of the non-treated leg, were then related to simultaneous changes in ABPI. RESULTS: Twenty-four hours following PTA, the calf volumes of both legs were decreased, although the ratio of the treated: untreated leg had increased by 2.4% (CI + 1.1-3.7, p < 0.01). After 1 week there was no difference in calf volume. These patterns were observed both in the 21 patients who had ABPI improvement of 0.15 or more 1 week following PTA, and in the 16 whose ABPI was unchanged. In the former group ABPI improved by a further 0.13 between 24 h and 1 week following PTA (p < 0.05), but there was no relationship between this delayed ABPI increase and simultaneous changes in calf volume. CONCLUSIONS: We did not detect any significant calf swelling following PTA. Furthermore, changes in ABPI were not related to changes in calf volume.

The nature and importance of changes in toe-brachial pressure indices following percutaneous transluminal angioplasty for leg ischaemia.

OBJECTIVES: To document changes in toe-brachial pressure indices (TBPI) during the 6 months following percutaneous transluminal angioplasty (PTA) and relate these changes to restenosis. Furthermore, to ascertain the effect of administering a vasodilator, glyceryl trinitrate (GTN), immediately following PTA. DESIGN: Eighty-three technically successful PTA procedures were studied. Fifty-six were for intermittent claudication, 14 for ischaemic rest pain, and 13 for non-healing ulcers. Immediately following balloon dilatation an intra-arterial bolus of either 150 micrograms GTN, with or without a 10 mg GTN patch for 24 h, or a saline placebo was administered. TBPI were measured before and for 6 h after PTA and then at 24 h, 1 week, 1 month and 6 months. At this time, patency at the PTA site was determined by arteriography. RESULTS: There was continuing TBPI improvement over 1 month in patients given saline following PTA. In patients given GTN, peak TBPI was achieved by 1 week, and corresponded with the TBPI observed immediately following GTN administration. Restenosis occurred in 27 (33%) patients, and was significantly more frequent following the procedures for rest pain or ulceration, or where a TBPI increase of more than 0.15 by 1 week was observed. CONCLUSIONS: Haemodynamic changes following PTA continue for at least 1 month, can be modified by GTN administration, and are predictive of subsequent restenosis. Measuring the TBPI increase during the first week following PTA underestimates total improvement, and may give false reassurance with respect to recurrent disease.

Immediate cytodiagnosis and imaging in the clinical management of discrete benign breast lesions.

Benign breast disease accounts for the majority of referrals to a specialist breast clinic. Delayed investigation prolongs patient anxiety and increases outpatient waiting lists. Few centres offer the triple test of clinical examination, fine needle aspiration cytology (FNAC) and breast imaging by mammography and/or ultrasonography at initial presentation. We have analysed the practicality of such a service during the 12 months following its introduction in our district general hospital. We studied the cohort of 178 patients who presented with a discrete breast lump which was subsequently shown to be benign. A triple test was performed in 72% of all patients. In 100 patients (56%) this was performed at initial assessment. Of these, 87 had clinically benign disease confirmed by FNAC and breast imaging and they were informed of the results within 3 h. A triple assessment during the initial consultation allows the majority of patients with discrete benign breast disease to be given immediate reassurance.

Hypercoagulable abnormalities and postoperative failure of arterial reconstruction.

OBJECTIVES: To determine whether preoperative hypercoagulable abnormalities are independent risk-factors for the failure of arterial reconstruction in leg ischaemia. METHODS: Sixty consecutive patients were studied before, and for 1 year following, elective peripheral revascularisation. Antithrombin III, protein C and protein S levels, and tests for lupus anticoagulant were performed preoperatively, and then repeated on the first and third postoperative days and after 1 and 6 months. Heparin-associated thrombocytopenia was also investigated if there was a postoperative fall in platelet count greater than 100 x 10(9)/l. RESULTS: Forty-six (77%) procedures were performed for critical ischaemia and 15 (25%) involved infrapopliteal reconstruction. The nature of surgery or accepted risk factors for occlusion were comparable between the 40 (67%) patients with patent reconstructions at 1 year and the 20 (33%) who had suffered failure. Preoperative hypercoagulable abnormalities were detected in 21 (35%) patients, with a three times greater incidence in those whose reconstructions failed (65% vs. 20%, p < 0.01), and in 11 of 12 patients suffering early (within 1 month) occlusion. The lupus anticoagulant was more frequently detected when prosthetic grafts were already present (p < 0.05) and carried a positive predictive value for reocclusion of 67% (p < 0.01). All three postoperative deaths occurred in patients with low protein S levels before surgery. CONCLUSIONS: Hypercoagulable abnormalities are common prior to arterial revascularisation and are independently associated with subsequent failure.

The predictive value of laser Doppler fluxmetry and transcutaneous oximetry for clinical outcome in patients undergoing revascularisation for severe leg ischaemia.

OBJECTIVES: To investigate the predictive value of laser Doppler fluxmetry and transcutaneous oximetry in 41 patients undergoing technically successful revascularisation for severe leg ischaemia. DESIGN: Toe and ankle systolic arterial pressures, transcutaneous oxygen tension (tcpO2), and stressed laser Doppler fluxmetry at the foot (time to peak laser Doppler flux following 2 min arterial occlusion, tp LDF, and the response of LDF to raising the leg 40 cm, the elevated:supine LDF ratio) were measured before revascularisation. Six months later these measurements were compared in those patients who were clinically improved, and those who still had symptoms of severe ischaemia or had lost their limb. SETTING: Vascular Laboratory, St. George's Hospital, London SW17, U.K. RESULTS: Six months following revascularisation 30 (73%) of the 41 patients had partial or complete symptomatic relief. Six (15%) had undergone major amputation and five (12%) still had symptoms of severe ischaemia. Before intervention toe and ankle systolic pressures were similar in the 30 who were improved and the 11 who had lost, or were still at risk of losing, their leg. Pre-revascularisation tcpO2 was significantly lower (18.3 mm Hg vs 33.5 mm Hg; p < 0.05) and tp LDF significantly longer (140 s vs 92 s; P < 0.05) in the 11 patients who were not clinically improved at 6 months. Whilst pre-revascularisation toe and ankle pressures below 30 mm Hg and 50 mm Hg respectively identified only 55% of those patients who were not improved 6 months later, a tp LDF in excess of 100 s identified 82% (p < 0.05) and was noted in five of the six amputees. CONCLUSION: Microcirculatory assessments performed in patients with limb-threatening ischaemia are likely to be more deranged in those patients who suffer clinical failure or amputation despite an apparently successful revascularisation procedure.

Clinical outcome and restenosis following percutaneous transluminal angioplasty for ischaemic rest pain or ulceration.

The role of percutaneous transluminal angioplasty in the management of severe leg ischaemia is controversial. To investigate further the efficacy of angioplasty and the clinical consequences of restenosis, a randomly selected cohort of 29 patients with ischaemic rest pain or ulceration was studied for 6 months after a technically successful balloon angioplasty. All patients had digital subtraction arteriography at the end of follow-up. Seven of 15 patients undergoing the procedure for rest pain had sustained relief from the initial dilatation. Partial or complete healing was noted in all 14 patients with ulceration and was maintained at 6 months in 11 despite significant (greater than 30 per cent) restenosis at the angioplasty site in eight. There were no complications or clinical deterioration associated with the procedure. Angioplasty is an effective method for treating the severely ischaemic leg, especially when used to achieve ulcer healing; restenosis is often clinically unimportant.

Hypercoagulable states in patients with leg ischaemia.

Hypercoagulable states are found in up to 10 per cent of patients with a history of unexplained venous thrombosis. To investigate the prevalence in arterial thrombosis, thrombophilia screening was performed on 124 patients who had previously undergone lower-limb revascularization, 45 claudicants and 27 controls. Of the patients who had undergone revascularization 40 per cent had a hypercoagulation abnormality (low levels of protein C, protein S and antithrombin III or presence of the lupus anticoagulant) in comparison with 27 per cent of claudicants and 11 per cent of controls (P < 0.01). Furthermore, patients who had suffered reocclusion after revascularization were significantly more likely to have a hypercoagulation abnormality than those who had not (P < 0.05), even if the occlusion had occurred more than 6 months previously. Lupus anticoagulant was the abnormality most frequently detected and, like low protein C levels, was found only in patients with peripheral vascular disease. It appears that hypercoagulable states are common in patients with arterial disease and may predispose to failure of revascularization.

Reliability of ankle:brachial pressure index measurement by junior doctors.

Ankle:brachial pressure index (ABPI) measurements are often performed by junior medical staff with little experience of the technique. The accuracy of such measurements is unknown. Two newly qualified doctors with no training in the use of Doppler ultrasonographic flowmeters performed ABPI measurement in 38 limbs (experiment 1). Two other newly qualified doctors then underwent a formal training session before, as well as continuous instruction during, ABPI measurements in 23 limbs (experiment 2). The doctors' measurements were compared with those obtained by experienced vascular technicians. The mean difference in ABPI measurement between the doctors and technicians in experiment 1 was greater than that in experiment 2 at both the dorsalis pedis (P < 0.05) and posterior tibial arteries. Nearly 30 per cent of the doctors' ABPI measurements in experiment 1 differed from those of the technicians by more than 0.15, in comparison with only 15 per cent of the measurements performed in experiment 2. Junior doctors should undergo formal training before performing ABPI measurements.

The differences in early haemodynamic response between surgery and angioplasty after successful re-opening of the superficial femoral artery.

In 40 patients with superficial femoral artery disease we prospectively evaluated the effect of angioplasty (n = 20) or femoropopliteal bypass (n = 20) on the ankle-brachial pressure index (ABI) using the Doppler ultrasound probe. The ABI was measured as a baseline 1 day before the procedure, 1 day after the procedure and 30 days later. In the angioplasty group the baseline ABI was 0.57 (0.11), increasing to 0.74 (0.26) 1 day postangioplasty and increasing further to 0.88 (0.26) after 30 days. The increase in ABI over 30 days was significantly greater than the increase over 1 day. In the femoropopliteal bypass group the baseline ABI was lower at 0.46 (0.17). However 1 day postoperatively it had increased to 0.92 (0.2) with almost no further increase at 30 days [0.95 (0.17)]. We concluded that by contrast to a surgical bypass where there was a large improvement in the ABI over the first day, the ABI following angioplasty continued to improve significantly beyond the first day.

Patient tolerance of the early introduction of oral fluids after laparotomy.

Early introduction of oral fluids after laparotomy permits effective hydration and earlier introduction of diet. Whether patients find such regimens difficult to tolerate has not been properly studied. A series of 60 consecutive patients undergoing abdominal surgery were randomised to receive oral fluids ad libitum from the first postoperative day (group 1) or in the traditional graduated regimen of 30 ml/h for 24 h, 60 ml/h for 24 h, 90 ml/h for 24 h and then free fluids (group 2). Patients were assessed daily with regard to objective and subjective criteria of hydration and nausea as well as noting time to bowel activity and days of first meal and discharge. Both groups had similar changes in serum urea, haematocrit and urine specific gravity; frequency of vomiting and antiemetic usage were also comparable. Patients in group 1 drank more (P < 0.001), however, and consequently felt less dehydrated. Discontinuation of intravenous fluids and ingestion of the first meal were also achieved 24 h earlier in this group.