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Objectives Several plaque and lesion characteristics have been associated with an increased risk for procedural stroke during or shortly after carotid artery stenting (CAS). While technical advancements in stent design and cerebral protection devices (CPD) may help reduce the procedural stroke risk, and anatomy remains important, tailoring stenting procedures according to plaque and lesion characteristics might be a useful strategy in reducing stroke associated with CAS. In this descriptive report of the ongoing Asymptomatic Carotid Surgery Trial-2 (ACST-2), it was assessed whether choice for stent and use or type of CPD was influenced by plaque and lesion characteristics. Materials and methods Trial patients who underwent CAS between 2008 and 2015 were included in this study. Chi-square statistics were used to study the effects of plaque echolucency, ipsilateral preocclusive disease (90–99%), and contralateral high-grade stenosis (>50%) or occlusion of the carotid artery on interventionalists' choice for stent and CPD. Differences in treatment preference between specialties were also analysed. Results In this study, 831 patients from 88 ACST-2 centres were included. Almost all procedures were performed by either interventional radiologists (50%) or vascular surgeons (45%). Plaque echolucency, ipsilateral preocclusive disease (90–99%), and significant contralateral stenosis (>50%) or occlusion did not affect the choice of stent or either the use of cerebral protection and type of CPD employed (i.e., filter/flow reversal). Vascular surgeons used a CPD significantly more often than interventional radiologists (98.6% vs. 76.3%; p < .001), but this choice did not appear to be dependent on patient characteristics. Conclusions In ACST-2, plaque characteristics and severity of stenosis did not primarily determine interventionalists' choice of stent or use or type of CPD, suggesting that other factors, such as vascular anatomy or personal and centre preference, may be more important. Stent and CPD use was highly heterogeneous among participating European centres.

ObjectivesTo test if initial high-dose, pulse-spray thrombolysis improves the early and late outcome of lower limb ischaemia as compared with low-dose infusion alone.DesignProspective randomised multicentre study.Material and methodsPatients with acute and sub-acute (

Aim:To investigate a series of patients with secondary aortoenteric fistulas and compare it with a previous series (1985–93 vs. 1973–84).Design:Retrospective study of medical records.Setting:Sixteen vascular surgical centres in Sweden.Patients:Twenty-seven patients were identified making an overall incidence of 0.5% of all aortoiliac operations. Among aneurysm patients the incidence was significantly lower than in the previous series. One patient record could not be identified. Fourteen primary operations were for aortic aneurysm, 12 for occlusive disease and one was an aortorenal vein bypass.Results:Symptoms of the fistula occurred after a median interval of 90 months which is significantly later than the previous series (32 months; p < 0.05). The commonest presentation was bleeding followed by septis. The median diagnostic delay was 10.5 days, which was significantly shorter than in the previous series. Most fistulas involved the duodenum (88%). One patient died before surgery. The postoperative mortality was 28%, significantly lower than in the previous series (58%) (p < 0.05). At the end of follow up (median 43 months) significantly more patients were alive than in the previous series (42% vs. 18%) (p < 0.05).Conclusion:Over a 21 year period there seems to have been a decrease in the frequency of secondary aortoenteric fistulas after aneurysm surgery, a longer interval before they occur, a shorter diagnostic delay, and a better survival.

Reperfusion of ischaemic skeletal muscle may lead to increased vascular permeability, oedema and ultimately muscle necrosis. Oxygen-derived free radicals have been suggested as aetiological factors in reperfusion injury. Amputated rabbit hindlimbs were subjected to 4 h of ischaemia followed by 2 h or reperfusion with Krebs' buffer. One limb from each animal was reperfused with oxygen-saturated buffer (reoxygenated limb) while the other limb was reperfused with nitrogen-saturated buffer (non-reoxygenated limb). Six animals received allopurinol orally 2 days prior to the experiment and ten animals received no treatment. The energy charge dropped from 0.90 to 0.54 during ischaemia and increased to 0.82 after reperfusion with oxygenated perfusate. Oedema was determined by limb weight and water content in muscle biopsies and muscle injury was assessed by uptake of [Tc99]methylenediphosphonate ([Tc99]MDP). The results were expressed in ratios, between the reoxygenated and nonreoxygenated limb. Without allopurinol treatment, the increase in water content and limb weight in reoxygenated limbs exceeded (p less than 0.05) non-reoxygenated limbs (ratios = 1.73 and 1.89, respectively). Allopurinol treatment significantly reduced (p less than 0.05 and p less than 0.02, respectively) the increase in water content and limb weight (ratios = 0.54 and 1.01, respectively). Without treatment, [Tc99]MDP-uptake was greater (p less than 0.05) in reoxygenated limbs than in non-reoxygenated limbs (ratio = 1.60). Allopurinol treatment significantly reduced (p less than 0.002) [Tc99]MDP-uptake in reoxygenated limbs (ratio = 0.80). These results demonstrate that additional injury to ischaemic skeletal muscle occurs during reperfusion with oxygen.(ABSTRACT TRUNCATED AT 250 WORDS)

Objectives: To find variables associated with outcome following thrombolytic treatment for acute lower limb ischemia. Design: Re-analysis of a prospective multicentre study. Material and methods: One hundred and twenty-one patients with acute lower limb ischemia previously included in a randomised study comparing high- with low-dose thrombolysis were re-analysed ignoring the mode of lytic treatment. All possibly predictive variables were subjected to multivariate analyses to find associations with outcome. Results: Previous successful thrombolysis, ankle-brachial index over 0.33, absence of motor dysfunction, presence of cardiac arrhythmia, and lysis of a vascular graft were all associated with successful thrombolysis (p = 0.003). Previous thrombolysis, age less than 70 years, and ankle-brachial index over 0.33 were all perfect predictors of absence of life-threatening complications or death. Successful lysis, age < 70, and lysis of a native artery as opposed to a vascular graft were all associated with clinical success (preserved patency, limb, and life) after one year (p = 0.002). Conclusions: Previous thrombolysis, age under 70 years, and non-severe ischemia predict successful thrombolysis free from severe complications. Successful thrombolysis is strongly predictive of amputation-free survival with vascular patency for at least one year. Occluded grafts could often be reopened, but long-term outcome is better after thrombolysis of native arteries. (C) 2008 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved. (Less)

Thirty limbs in 25 patients with chronic deep venous insufficiency and recurrent ulceration were examined by ascending and descending contrast phlebography, occlusion plethysmography, foot volumetry and ambulatory venous pressure. Superficial venous insufficiency was surgically corrected by stripping of the saphenous vein and local excision of the varicosities (op1) in 12 limbs. Perforating venous insufficiency was then corrected by extensive subfascial ligation of perforating veins (op2) in all limbs. Venous outflow capacity, measured by occlusion plethysmography, and muscle pump function, measured by foot volumetry, were not affected by either procedure. Venous reflux, measured by foot volumetry, (Q/EVrel) and by venous pressure return time (RT90) improved significantly with op1 but no change was seen after op2. Venous hypertension decreased significantly with op1 but did not change after op2, and 59% of the limbs still had severe venous hypertension (> 60 mmHg) after both procedures. Initial clinical results were good, ulcers persisting in only three limbs, but recurrences occurred in an additional six limbs within 27 months. The limbs with persistent or recurrent ulcers had severe phlebographic reflux and severe venous hypertension. These results demonstrate that improvement in venous reflux and hypertension may be achieved by correction of superficial venous insufficiency, but the addition of ligation of perforating veins seems to be of less benefit to the venous circulation.

Objectives:To study if venous thrombectomy prevents late post-thrombotic sequelae, venous obstruction reflux, and improves venous physiology following an acute iliofemoral venous thrombosis.Design:Prospective randomised controlled study.Material:Thirty patients returned for follow-up 10 years after an acute iliofemoral venous thrombosis initially treated with conventional anticoagulation treatment (medical group, n = 17) or with thrombectomy combined with a temporary arteriovenous fistula and anticoagulation (surgical group, n = 13). Clinical assessment, radionuclide angiography, duplex ultrasound and venous physiology tests were performed.Results:Leg swelling was recorded in 12 (71%) and leg ulcers in three (18%) of the medical patients and in, respectively, six (46%) and one (8%) of the surgical patients. The surgical patients had less severe sequelae (class 0–2). Radionuclide angiography demonstrated that the iliac vein was more commonly occluded following medical (59%) than following surgical (17%) treatment (p

To study the effect of polymorphonuclear leucocytes (PMNLs) on reperfusion injury in rabbit skeletal muscle and to evaluate the role of oxygen-derived free radicals in PMNL-mediated reperfusion injury.An isolated rabbit limb perfusion model. Amputated hindlimbs were subjected to 4 hours of ischaemia followed by 2 hours of reperfusion with oxygenated Krebs' buffer.Department of experimental surgery.14 rabbits.In group I (n = 8), one limb from each animal was reperfused with PMNL-supplemented buffer while the other limb was reperfused with cell-free buffer (control). In group II (n = 6), SOD and catalase were added to the limb reperfused with PMNL-supplemented buffer while the other limb was reperfused with cell-free buffer without SOD and catalase (control).PMNL accumulation as myeloperoxidase (MPO) activity, muscle necrosis as uptake of [Tc99]methylenediphosphonate (MDP), and oedema as increase in muscle water content (MWC). Electron microscopy was performed for histological demonstration of reperfusion injury.Addition of PMNLs increased MPO activity (p0.05) and MDP uptake (p0.05) but did not affect MWC. SOD and catalase treatment of limbs perfused with PMNLs prevented the increase in MPO activity (p0.05) and reduced MDP uptake (p0.05) and MWC (p0.05). PMNLs aggravated histological changes seen after reperfusion.Reperfusion injury in skeletal muscle is, at least partially, mediated by PMNLs. Free radical scavengers reduce PMNL-dependent injury and prevent PMNL accumulation suggesting that oxygen-derived free radicals are mediators of PMNL-dependent injury and/or engaged in the interaction between PMNLs and the microvascular endothelium.

Mannitol has previously been shown to reduce skeletal muscle reperfusion injury and postischaemic compartment pressure. The present study was designed to evaluate whether these effects result from hyperosmolarity or free radical scavenging. A rabbit hindlimb perfusion model was used to compare the effects of mannitol (n = 6), glucose (n = 6)--an isomer of mannitol without scavenging effect--and fasciotomy (n = 6) on oedema, compartment pressure, energy charge, and muscle injury after 4 hours of ischaemia and 2 hours of reperfusion. One limb from each animal received treatment, while the other limb served as an untreated control. Mannitol and glucose reduced (p0.05) muscle water content and decreased (p0.01) the compartment pressure. Fasciotomy had no effect on muscle water content but normalised compartment pressure. The increase in energy charge following reperfusion was improved (p0.05) and uptake of [Tc99]methylenediphosphonate--an indicator of muscle injury--was reduced (p0.05) by mannitol only. In conclusion, mannitol reduces postischaemic oedema mainly by its hyperosmolar property whereas restitution of energy production and reduction of muscle necrosis seem to be an effect of free radical scavenging. The compartment pressure is reduced by hyperosmolarity and free radical scavenging.

To clarify the effects of ischaemia and reperfusion on membrane potential of skeletal muscle in rabbits, and to study its correlation with the energy charge and the lactate content.Open experimental study.20 isolated rabbits' hindlimbs.The femoral arteries were cannulated and the limbs amputated at the level of the hip joint. Blood was removed by thorough perfusion with Ringer's solution. Below knee fasciotomies were done, and the whole limbs were immersed in Ringer's solution during periods of ischaemia. Reperfusion was with a modified Krebs' buffer with Dextran T70 saturated with oxygen.Measurements of membrane potential; ATP, ADP, and AMP concentrations; and lactate concentrations in muscles after 1 (n = 8), 2 (n = 4), 4 (n = 4), or 6 (n = 4) hour periods of ischaemia followed by a 2 hour period of reperfusion compared with those in 4 limbs that were made ischaemic for 8 hours and not reperfused.During the first hour of ischaemia the membrane potential decreased from -90 mV to -63 mV and the energy charge remained unchanged at 0.9. After 8 hours of ischaemia the membrane potential had decreased to -20 mV, the energy charge was 0.2, and the lactate content had increased by a factor of 12. During reperfusion the membrane potential was restored only in limbs that had been subjected to 1 hour of ischaemia, whereas energy charge was also restored in those subjected to 2 and 4 hours of ischaemia. The lactate content decreased during reperfusion in all limbs.Assessment of membrane potential is more sensitive than that of energy charge as an indicator of recovery of skeletal muscle after a period of ischaemia followed by reperfusion.

To determine the chronological changes of venous physiology following major thromboses, 20 patients were repeatedly examined for over 5 years after an acute ilio-femoral thrombosis which was treated with conventional anticoagulation. Radionuclide angiography showed that 70% of the patients had obstructive lesions of the iliac vein with only minor changes occurring from 6 months to 5 years. In spite of this, the plethysmographic maximum venous outflow increased from 31 to 45 ml/min/100 ml (P less than 0.001). The foot volumetric reflux did not change with time and about half of the patients had abnormal values. Venous reflux assessed by the refill time of foot vein pressure, deteriorated with time (P less than 0.05), and at 5 years all but one patient had a refill time less than 20 s. The muscle pump function, examined by foot volumetry, was abnormally low in about half of the patients throughout the study. The ambulatory foot vein pressure was constantly pathological (greater than 60 mmHg) in half of the patients and only two of 18 patients had normal values (less than 45 mmHg) at 5 years. Five patients with thromboses involving only the proximal veins had better physiological results than 15 patients with thromboses that extended to the peripheral veins. Three patients who developed venous claudication had iliac vein obstruction and an impaired venous outflow and three patients who developed venous ulcers had venous reflux and severe venous hypertension. Although venous outflow continuously improves following ilio-femoral thromboses, valvular competence and muscle pump function are constantly pathological, creating severe venous hypertension with a risk of post-thrombotic sequelae.

The objectives of treatment in iliofemoral venous thrombosis are to prevent fatal pulmonary embolism, further swelling of the leg with development of phlegmasia caerulea dolens and the severe post-thrombotic syndrome, by preservation of venous patency and normal valves. The experience of thrombectomy and temporary AVF are presented in 155 patients where technical details of management are emphasized. A new technique with percutaneous closure of the AVF after six weeks is described. No patient died due to fatal pulmonary embolism during or immediately after surgery. In a randomized study comparing surgery with conventional anticoagulant treatment follow-up venography of the iliofemoral segment demonstrated excellent results in 76% of the operated group and 36% in the conservatively treated group, while venography of the femoropopliteal segment revealed an occlusion in about one-third of the patients in both groups. Of the patients who had an open femoropopliteal segment it was noted that 52% in the surgical group and 26% in the conservative group had preserved valves with no reflux.

The present investigation was performed to study the aetiological importance of abnormal coagulation or defective fibrinolysis in the development of deep venous thrombosis (DVT). Sixty-nine patients with acute iliofemoral venous thrombosis were subjected to evaluation of coagulation and fibrinolytic parameters. Defective fibrinolysis, usually with an increased activity of the rapid tissue plasminogen inhibitor, was detected in 31 patients (45%), and increased factor VIII with normal fibrinogen was recorded in 10 patients (14%). Two patients had a hereditary deficiency of plasminogen and protein C, respectively, and a lupus anticoagulant was demonstrated in another patient. Antithrombin III deficiency was not detected in any patient. Abnormal findings were most frequently recorded in patients with ‘idiopathic’ DVT. Although the exact relationship between the development of DVT and the recorded abnormalities could not be determined in all instances, it is obvious that defective vessel wall fibrinolysis and increased factor VIII are frequently recorded in patients with extensive DVT of the lower limb. Pathological alternations of antithrombin III, plasminogen and protein C seem to be less common.

Previous reports have advocated preclotting and autoclaving of Dacron grafts to prevent graft hemorrhage, yet no data delineate possible changes in surface thrombogenicity or thromboembolic risks. To assess these factors, preclotted and preclotted-autoclaved woven Dacron prostheses were implanted in the thoracic aorta of 31 dogs. Grafts were harvested 1 week to 1 month following implantation, and the thrombus-free surface of each graft was calculated by computerized morphometry. Values for thrombus-free surface were lowest in autoclaved grafts preclotted in nonheparinized blood (72%) or in heparinized blood (78%). Grafts preclotted in platelet-rich plasma and autoclaved had a thrombus-free surface value of 85%. Regular preclotted grafts or grafts without preclotting had the greatest thrombus-free surface value (97% and 99%). Distal embolization to the kidneys was detected in seven of 31 animals (23%). No emboli were found in animals with grafts that were not preclotted or if grafts were preclotted with platelet-rich plasma and autoclaved. Thrombus-free surface values were lower (p less than 0.01) in grafts with embolic complications (71% versus 91%). These data suggest that, if the risk of severe bleeding in fully heparinized patients precludes the use of a woven Dacron graft without preclotting, autoclaving a graft preclotted with platelet-rich plasma appears to be the method of choice.

Thrombogenicity of graft material, low velocity of blood flow, and wall collapsibility have been cited as the main factors responsible for the high occlusion rate of vascular prostheses placed in the venous system. This study was performed to analyze the effects of measures taken to overcome each of these factors. The thrombogenicity of expanded polytetrafluoroethylene (ePTFE) was evaluated by determination of the 3-hour deposition of radionuclide-labeled platelets and fibrin on grafts placed in the infrarenal vena cava of 18 dogs. Wetting the prosthesis with heparin before implantation significantly decreased platelet deposition at the cranial anastomosis (p less than 0.025) and on the graft surface (p less than 0.01), whereas the decrease of fibrin deposition was not statistically significant. The effects of flow velocity and graft support were studied in 44 dogs subjected to iliocaval bypass. The results of these studies demonstrated that a flow-increasing arteriovenous fistula was necessary to maintain patency of ePTFE grafts (p less than 0.01) but did not enhance patency of autogenous vein grafts. External ring support of ePTFE grafts did not significantly improve early patency. Decreasing thrombogenicity by wetting the grafts with heparin and increasing the blood flow by constructing an arteriovenous fistula helps in overcoming failure of venous vascular prostheses.

Ninety-three patients with treatment-resistant venous ulcers were included in a multicentre randomized trial to compare cadexomer iodine and the standard treatment used in each centre combined with compression bandages, in healing venous ulcers. The mean duration of ulcers before the trial was more than 2 years. With standard treatment the mean ulcer size increased slightly during the 6-week trial whereas with cadexomer iodine the ulcer size was significantly reduced. Cadexomer iodine was more effective than standard treatment for reduction of pain, removal of pus and debris, removal of exudate, stimulation of granulation and reduction of surrounding erythema. Bacterial infection of ulcers increased or did not change during treatment with the standard therapy whereas cadexomer iodine significantly reduced infection with Staphylococcus aureus, Pseudomonas aeruginosa and other pathogenic organisms. A correlation was seen between the time taken to reduce or eliminate infection with Staphylococcus aureus and rate of ulcer healing. Four patients complained of transient pain in the ulcer after application of the cadexomer iodine. It is concluded that cadexomer iodine increased the rate of healing of infected chronic venous ulcers.

Fifteen patients were operated on for compression of the celiac artery with division of the median arcuate ligament. Initially most patients were released from their preoperative abdominal pain. At follow-up after 1 1/2-9 1/2 years only two patients were asymptomatic. Our results corroborate the nonentity of the celiac compression syndrome. The existence and identification of a subgroup of patients with symptomatic compression of the celiac artery is discussed.

The treatment of choice in acute iliofemoral venous thrombosis is still controversial. This prospective randomized study compares the results of conventional anticoagulation of 32 patients with the results obtained in 31 patients undergoing acute thrombectomy combined with a temporary arteriovenous fistula and anticoagulation. Early complications were few in both treatment groups, and significant pulmonary embolism developed in only one conservatively treated patient. At 6-month follow-up in all surviving patients, leg swelling, varicose veins, and venous claudication were more frequent after conservative treatment. Only 7% (2 of 27) of these patients were completely free from postthrombotic symptoms compared with 42% (10 of 24) of the operated patients (p less than 0.005). Contrast phlebography demonstrated an excellent venous outflow through the iliofemoral segment in 35% (9 of 26) of the conservatively treated and in 76% (16 of 21) of the operated patients (p less than 0.025). Open femoropopliteal veins with competent valves were recorded in 26% (7 of 27) in the conservative group and in 52% (12 of 23) in the thrombectomy group (p less than 0.05). Thus thrombectomy combined with arteriovenous fistula decreases early symptoms and preserves venous outflow and valvular function better than conservative treatment. This procedure is therefore recommended for young patients with acute iliofemoral thrombosis to avoid development of incapacitating postthrombotic sequelae.

Ten patients with congenital vein valve aplasia verified at contrast phlebography were evaluated clinically and by physiologic examinations. All had orthostatic edema and varicose veins, but leg ulcers and other "postphlebitic" sequelae were infrequent. Foot volumetry and measurement of ambulatory foot vein pressures revealed a severe deep venous incompetence with a defective muscle pump function and considerable reflux. Eight limbs were operated on with conventional varicose vein surgery and physiologically re-examined six to 26 weeks after the operation. All had an improved ambulatory pressure reduction (p less than 0.001). Foot volumetry revealed better muscle pump function (p less than 0.01), while the reflux flow was unchanged. Surgery of the incompetent superficial venous system is therefore recommended in cases with deep venous insufficiency due to congenital vein valve aplasia.

To evaluate the potential benefit of endothelial seeding of venous prostheses, 20 dogs were subjected to iliocaval reconstruction with expanded polytetrafluoroethylene grafts protected by an arteriovenous fistula. Grafts seeded with enzymatically derived endothelial cells were compared with control grafts that were sham seeded with culture medium and blood. Five seeded and seven sham-seeded grafts remained patient and were perfusion fixed in situ 4 to 6 weeks after operation. Specimens were examined by light, scanning, and transmission electron microscopy. No statistical difference in early patency was noted. The mean thrombus-free surface area was 80% in the seeded and 71% in the sham-seeded group. Light microscopy of these areas revealed a monocellular layer lining the lumen in all grafts. Scanning electron microscopy demonstrated a thin cellular lining covering 50% to 100% of the specimens' surface area in four of the five seeded and five of seven sham-seeded grafts. Transmission electron microscopy revealed these cells to exhibit characteristics typical of endothelial cells. The subcellular layer was equally thin in both groups. Early patency rates were not benefited by endothelial seeding of grafts placed in the venous system. Seeding of grafts with enzymatically derived endothelial cells provides a good endothelial cover with a thin subendothelial layer but not to a greater extent than does sham seeding of the venous prostheses.

In this follow-up of 1,112 patients operated on for abdominal aortic aneurysm (AAA) it was noted that cerebrovascular accidents (CVAs) caused significant (8.2%) late mortality. Seventy-one patients developed non-fatal or fatal CVAs at 5.9 +/- 2.9 (mean +/- SD) years after the initial aneurysm repair. The incidence of CVA was 4.2% and 9.5% within five and ten years, respectively. In patients with preoperative evidence of both hypertension and heart disease, the incidence of CVA within five years was 9.1% compared to an incidence less than 4% in patients with either or neither of these risk factors (p less than 0.01). Multivariate analysis of individual risk factors revealed that only age (p less than 0.001), hypertension (p less than 0.001), angina pectoris (p less than 0.02) and other heart disease (p less than 0.001) were independently associated with a reduced survival free of CVA. Thus, cerebrovascular accidents are responsible for significant late morbidity after AAA repair. Patients at high age or with evidence of hypertension and heart disease carry a greater risk for this complication.

Radionuclide angiography (RNA), was compared to contrast phlebography (CP) for evaluation of iliofemoral venous patency. Twenty-three patients that six months earlier had been treated for iliofemoral venous thrombosis were investigated. The reproducibility of RNA was good as the interindividual and intraindividual variation was 80-85% and 90-95% respectively. The sensitivity of RNA was 91% in the iliac and 65% in the femoral segment. The specificity was 78% in the iliac and 74% in the femoral segment. The advantages as compared to CP are: easy performance, easy to repeat, no adverse reactions and visualization of the whole venous system. The disadvantages are: e.g. difficulties in interpretation in bilateral disease or abnormal anatomy. RNA is recommended as a screening method for suspected iliac venous obstruction and for follow-up of venous patency after iliofemoral venous thrombosis.

Some of the pitfalls in the management of inflammatory abdominal aortic aneurysm are stressed in the presentation of six illustrative cases. Background data on the presumed etiology and common symptoms are provided. The diagnostic value of computed tomography for preoperative detection of the fibrosis surrounding these aneurysms and the differentiation from other conditions are also discussed.

The pharmacokinetics of trimethoprim-sulphamethoxazole was examined in seven malnourished (marasmic) infants receiving cotrimoxazole (CMZ) for treatment of urinary tract infection. Comparisons were made with the SMZ level of ten nutritionally normal infants, hospitalized for first and second degree burns, receiving CMZ for treatment of bronchitis. CMZ was administered as an oral suspension (20 mg TMP and 100 mg SMZ, 5 ml), patients receiving 22 mg SMZ/kg body weight. Capillary blood samples, 0.05 ml were taken at prescribed intervals. Elimination half-life of SMZ in the marasmic infants was prolonged, 9.6 vs 4.9 hr, in their eutrophic counterparts. In addition, greater area under the curve (AUC), 573 vs 328 micrograms/ml/h, was noted in the malnourished group. This disparity may be due to differences in body fluid distribution between the two groups.

Fifteen premenopausal women had by-pass reconstruction performed for aorto-iliac disease. A high prevalence of smoking, oral contraception and hyperlipemia was found. The outcome of reconstructive surgery was initially excellent. Serious complications and progress of the arteriosclerosis, however, made the late results more doubtful.15 young women who were operated upon for aorto-iliac disease were retrospectively studied. Etiological factors, preoperative examinations and treatment results were evaluated. The age range of the women, who were operated upon in surgery departments in Helsingborg and Lund, Sweden from 1974 to 1979, was 25 to 51 years. All the women were smokers. Oral contraceptive (OC) use for several years was present in 14 patients, 4 of whom had stopped 3-6 years prior to surgery. 1 woman had an artificial menopause performed in 1975. 11 of the patients were treated for hyperlipemia or had abnormal concentrations of serum lipids. A conservative treatment regime instituted in all patients was unsuccessful. Reconstruction was performed with bifurcation prostheses in 12 patients, with axillo-bifemoral, iliaco-femor-femoral and femor-femoral cross-over bypass using Gore-Tex in another 3 patients, respectively. The ischemic symptoms disappeared in all patients. There was no mortality, wound infection or graft thrombosis during the first 30 postoperative days. 2 patients suffered a temporary respiratory insufficiency. Severe late complications occurred in 3 instances. There were 2 graft thromboses within the 1st postoperative year, requiring below-knee amputation in 1 patient and bilateral above-knee amputation in the other, who died from circulatory collapse shortly afterwards. 1 woman died 4 years after reconstruction with a bifurcation graft. All surviving patients were exmained during 1979. Observation time ranged from 6 months to 5 years. 9 patients were free from symptoms concerning their legs. 3 patients had recurrent disabling intermittent claudication and 1 patient was well rehabilitated with a below-knee amputation.

Congenital vein valve aplasia is often misdiagnosed and its symptoms misinterpreted as being caused by previous deep venous thrombosis. The present article reviews the literature providing data on etiology, symptomatology, and phlebographic appearance in congenital vein valve aplasia. A personal experience with 10 cases focuses on the clinico-physiological results with compression therapy and surgical treatment of superficial venous insufficiency. Compressive support with a tourniquet or a compressive stocking did not improve muscle pump function or venous reflux, as assessed by foot volumetry, and venous hypertension was not affected. Nevertheless, no patient developed leg ulcers during consistent use of compressive stockings. Surgical removal of incompetent saphenous veins, perforators, and varicosities in a subgroup of 6 patients (8 limbs) was followed by an improved muscle pump function and decreased venous hypertension which persisted 4 years post-operatively. Only 1 patient has been suited for deep venous reconstruction with transplantation of a valve-containing vein segment from the axillary vein to the popliteal vein, but it is still too early to assess the results of this procedure. Our findings demonstrate that consistent compressive therapy is paramount in the management of patients with congenital vein valve aplasia. Surgical treatment of the superficial venous insufficiency provides a long-lasting improvement of muscle pump function and venous hypertension. “Curative” vein valve transplantation or transposition is possible only in a minority of these patients.

The role of the temporary AV-fistula in venous reconstructive surgery is described. The objectives are: increase of blood flow in the proximal thrombectomised vein or in the venous graft; prevention of immediate re- or graft thrombosis; provide time for endothelial healing; promote development of collaterals in case of occlusion. The management of acute ilio-femoral venous thrombosis with thrombectomy and temporary AV-fistula is presented with results of 120 operations. No mortality due to fatal pulmonary embolism. In the prospective randomised study comparing surgery with conservative treatment follow-up demonstrated 76% patent iliac veins in operated group compared to 35% in the conservative group. Ten patients with iliac vein obstruction had immediate reconstruction with PTFE graft and AV-fistula. Three grafts are still functioning after 7, 15 and 56 months respectively.

Serial perfusion lung scanning and chest radiography were used to study the incidence of pulmonary embolism in patients with acute iliofemoral venous thrombosis. The efficacy of conventional anticoagulation and surgical thrombectomy in controlling embolism and the risk of creating emboli during thrombectomy were also evaluated. Lung scans obtained on admission in 49 patients were normal in 37 per cent, inconclusive in 18 per cent and positive for embolism in 45 per cent of the patients. Symptoms suggestive of embolism were present in only 24 per cent of the patients and correlated poorly with lung scans. Massive embolism was present in only two patients. Additional, usually asymptomatic, emboli developed within one month in 21 per cent of 29 patients treated conservatively with anticoagulation alone and in 20 per cent of 20 patients having acute thrombectomy combined with a temporary arteriovenous fistula and systemic anticoagulation. Only one conservatively treated patient required caval interruption. Pulmonary embolism, usually of minor degree, is thus present in nearly every other patient with acute iliofemoral venous thrombosis. Anticoagulation alone or in conjunction with thrombectomy and arteriovenous fistula in most cases effectively prevents further embolization and the risk of creating additional emboli by the surgical procedure is insignificant.

For comparative analysis of small vessel prostheses, 78 dogs underwent femoral artery replacement with autogenous vein, polytetrafluoroethylene (PTFE) or human umbilical vein (HUV) grafts. Thirty-six animals received antiplatelet therapy with piroxicam orally once a day. Three-hour deposition of 111In-labeled platelets was less on HUV than on PTFE grafts but still greater than on autogenous vein grafts. Accordingly, 3-hour patency rates were lowest with PTFE and highest with autogenous vein, although the difference between HUV and PTFE grafts was not statistically significant. One month following implantation, PTFE grafts had a higher patency rate than HUV grafts (p less than 0.05). Treatment with piroxicam decreased 3-hour platelet deposition, improved 1-month patency of both PTFE (p less than 0.05) and HUV (p less than 0.01) grafts, and decreased pseudointimal thickening on PTFE grafts (p less than 0.01). This experimental study did not demonstrate any clearcut difference in the performance of PTFE and HUV grafts. Piroxicam treatment improved the results with both grafts, which would justify future clinical trials with this simple antiplatelet regimen.

Nine patients with chronic iliac vein obstruction and venous claudication were investigated. Intramuscular pressure was measured in the anterior tibial and the deep posterior compartments in both legs at rest and during exercise. The pressures were significantly higher in the leg with iliac vein obstruction (39 +/- 10 mm Hg) than in the contralateral leg (26 +/- 12 mm Hg) at rest as well as during exercise (60 +/- 16 mm Hg and 41 +/- 15 mm Hg, respectively) in the deep posterior compartment. Similar changes were observed in the anterior tibial compartment. Muscle water content was higher (P less than 0.01) in the obstructed leg and contributes to the explanation for the high intramuscular pressure in this leg. Muscle blood flow, adenosine triphosphate, phosphocreatine, and lactate were determined in the gastrocnemius muscles at rest and at exercise. Muscle blood flow, measured with the 133xenon clearance technique, was lower in the obstructed leg (17.5 ml/min, 100 gm) than in the control leg (28.1 ml/min, 100 gm) during exercise. Lactate increased more (P less than 0.05) in the obstructed leg. It is suggested that pain in venous claudication is caused by the high intramuscular pressure, and therefore fasciotomy may be useful in the treatment of this disorder.

Twenty-eight consecutive cases of acute superficial thrombophlebitis of the long saphenous vein above the knee were reviewed concerning presence of asymptomatic deep venous thrombosis and pulmonary embolism and early clinical results after surgical treatment. Contrast phlebography of the ipsilateral leg revealed asymptomatic involvement of major deep veins of the thigh or calf in 4 of 21 examined patients. Perfusion lung scanning and chest radiography demonstrated typical segmental perfusion defects consistent with pulmonary embolism in two of ten examined patients. High ligation and stripping of the phlebitic veins gave prompt cure in 19 patients, though in two who were simultaneously treated with anticoagulants there was troublesome bleeding. Simple high ligation was performed in nine patients without complications, but four of them had protracted phlebitic pain. The results indicated that preoperative phlebography and lung scanning are helpful in detecting associated asymptomatic disorders and for planning therapy in patients with clinically isolated, superficial thrombophlebitis of the long saphenous vein. The treatment of choice is acute high ligation with removal of all phlebitic veins. If anticoagulation is indicated because of concomitant deep venous thrombosis or pulmonary embolism, the initial procedure should preferably be limited to high ligation.

The results of iliac vein reconstruction performed early after secondary iliofemoral venous thrombosis were retrospectively evaluated. The review comprised seven patients who underwent acute thrombectomy combined with cross-femoral (4 cases) or iliocaval (3 cases) bypass procedures using polytetrafluoroethylene (PTFE) grafts. The clinical course, graft patency and venous physiology were studied. Five patients had a satisfactory clinical course, but one patient died of postoperative complications and another underwent leg amputation after 20 months. Contrast and radionuclide phlebograms showed that only two grafts were still patent after two years, but only one of these was still patent five years postoperatively. Clinical symptoms and physiologic parameters correlated poorly with graft patency, demonstrating the necessity of phlebography in evaluating patency rates after venous surgery. Our study indicates that early venous reconstruction using PTFE grafts does not result in satisfactory long-term patency rates. Further development of graft materials suitable for the venous system is required.

To identify common etiologies and allow a selective and effective management of acute iliofemoral venous thrombosis, 128 patients treated surgically (97 cases) or medically (31 patients) were analysed regarding possible underlying conditions. Chart review revealed that prolonged immobilization (25%), recent surgery (20%), and neoplasm (16%) were the most frequent etiologic factors. No underlying cause was detected in 34% of the patients, but more than one possible etiology were recorded in 29% of the patients. Chronic compression of the iliac vein was present in at least 13% of the operated cases. The multifactorial etiologic spectrum in iliofemoral thrombosis is basically the same as in calf vein thrombosis. Iliac vein compression, childbearing and perhaps estrogen intake seem to be more often associated with iliofemoral thrombosis. Initial survey regarding underlying causes permits tailored management for the individual patient. Surgical treatment is often successful but thrombi that develop secondary to chronic vein obstruction or neoplasm are preferably treated conservatively.