Thrombophilia and venous thromboembolism. International consensus statement. Guidelines according to scientific evidence

Thrombophilia is the term now used to describe predisposition to increased risk of venous and occasionally arterial thromboembolism due to hematological abnormalities. It can be a multifactorial disorder where congenital defects of anticoagulant or procoagulant factors may be combined with acquired hematological abnormalities. It should be considered in patients with a documented unexplained thrombotic episode or a positive family history. The aim of this document is to provide guidelines for investigation and management of patients with thrombophilia in the presence or absence of venous thromboembolism (VTE).

Prevention of venous thrombosis in long-haul flights with Flite Tabs: the LONFLIT-FLITE randomized, controlled trial

The aim of this study was to evaluate the development of edema, and superficial and deep vein thrombosis (DVT) prophylaxis with an oral profibrinolytic agent (Flite Tabs, 150 mg pinokinase, Aidan, Tempe, AZ, USA) in long-haul flights (7-8 hours), in high-risk subjects. A group of 300 subjects was included; 76 were excluded for several problems including concomitant treatments; 204 were randomized into 2 groups (active treatment or placebo) to evaluate the effects of prophylaxis with Flite Tabs. An exercise program was used in both groups. The femoral, popliteal, tibial, and superficial veins were scanned with ultrasound before and within 90 minutes after flights. Of the included subjects, 92 of 103 controls and 94 of 101 treated subjects completed the study. Dropouts were due to connection problems. Age, gender, and risk distribution were comparable in the groups. In the treatment group, no DVT was observed. In the control group, 5 subjects (5.4%) had a DVT and there were 2 superficial thromboses (7 events in 92 subjects; 7.6%). At inclusion, edema was comparable in the 2 groups. After flights there was an increase in score in controls (+12%) in comparison with a decrease (-15%) in the Flite Tabs group (the difference in variation was statistically significant). Intention-to-treat analysis for thrombotic events shows 18 failures in controls (11 lost to follow-up + 7 thrombotic events) of 92 subjects (19.6%) in comparison with 7 failures (of 94 subjects, equivalent to 7.4%) in the treatment group (p < 0.05). Events were asymptomatic. In conclusion, Flite Tabs were effective in reducing thrombotic events and in controlling edema in high-risk subjects in long flights.

[Treatment of a femoral venous aneurysm with foam-sclerotherapy]

Venous aneurysms are uncommon. Venous dilatation and large varices could be treated with injections of foam and sclerosing agents followed by local compression which obliterate or thrombose the aneurysmal space. However, the use of foam-sclerotherapy to obliterate venous aneurysms has never been reported before. The obstruction or sclerosis of the aneurysmal space should be obtained without altering the femoral flow. The patient is a 65-year old lady without history of trauma involving the femoral region. A compressible lump is present at the third, internal part of the left femoral fold. The lump is painless and easily obliterated by compression. Color duplex shows a large cavity (4 x 4 x 6 cm) and venous flow is visible. Flow produces a venous jet, visible with color and ejecting from the common femoral vein. A first injection is made under ultrasound guide using a foaming agent: 10 ml of foam including 4 ml of 3% sclerosing solution are injected. During the injection the femoral vein is compressed with the probe to avoid passage of the sclerosing foam into the femoral vein. After 2 weeks, ultrasound indicate only a partial occlusion of the aneurysm. The procedure is repeated and after 2 more weeks the ultrasound scan shows a complete occlusion of the aneurysm. The femoral vein and the long saphenous vein are patent. After 12 weeks the situation is unchanged and the results appear to be permanent. This new method, never described before is an important, minimally invasive method in case of venous aneurysms. Results from larger studies should be available to define indications and modalities of treatment.

Prevention of Venous Thrombosis with Elastic Stockings During Long-Haul Flights: The LONFLIT 5 JAP Study

The aim of this study was to evaluate deep venous thrombosis (DVT) prophylaxis with specific elastic stockings in longhaul flights (11-13 hours), in high-risk subjects. A group of 300 subjects was included; 76 were excluded for several problems including concomitant treatments; 224 were randomized into two groups (stockings vs. controls) to evaluate prophylaxis with below-knee stockings. An exercise program was used in both groups. Scholl (UK) Flight Socks (14-17 mmHg of pressure at the ankle) were used. DVT was diagnosed with ultrasound scanning. The femoral, popliteal, and tibial veins were scanned before and within 90 minutes after the flights. Of the 205 included subjects, 102 controls and 103 treated subjects completed the study. Drop-outs were due to flight connection problems. Age, gender, and risk distributions were comparable in the two groups. In the treatment group (103 subjects; mean age, 42; SD 9; M:F, 55:48), one limited, distal DVT was observed (0.97%). In the control group (102 subjects; mean age, 42.1; SD 10.3; M:F, 56:46), six subjects (5.8%) had a DVT. There were no superficial thromboses. The difference in DVT incidence is significant (p<0.0025; six times greater in the control group). Intention-to-treat analysis counts 18 failures in the control group (12 lost to follow-up + six thromboses) of 112 subjects (15.8%) versus eight failures (7.3%) in the treatment group (p<0.05). The tolerability of the stockings was very good and there were no complaints or side effects. All events were asymptomatic. Considering these observations, Scholl Flight Socks are effective in reducing the incidence of DVT in high-risk subjects.

Improvement of microcirculation and healing of venous hypertension and ulcers with Crystacide. Evaluation of free radicals, laser Doppler flux and PO2. A prospective-randomized-controlled study

In 20 patients with chronic venous insufficiency and venous hypertension associated with ulcerations, the effects of a new compound, applied onto the skin (Crystacide) were assessed in a randomized, controlled study. Duplex scanning was used to assess the presence of venous obstruction and incompetence, and microcirculatory methods were used to assess and quantify venous microangiopathy and to follow up subjects after local treatment with Crystacide. Laser Doppler flowmetry (LDF) was used to assess skin perfusion in association with transcutaneous (tc) partial pressure of oxygen (PO2) measurements. Local plasma free radicals (PFR) were evaluated in the area surrounding the venous ulcer, with the D-Rom test. Crystacide was applied around and on the ulcer for 10 days. Crystacide was more effective than the control treatment: PO2 was increased, PFR and LDF were decreased (flux increase is associated with venous hypertension), and the ulcer area was significantly smaller at 10 days in the Crystacide group in comparison with the placebo group (p<0.05). In conclusion, in venous ulcerations, local treatment with Crystacide (10 days) improves the microcirculation and decreases skin free radicals improving healing.

Improvement in walking ability, ankle pressure indices and quality of life in vascular claudication using intermittent pneumatic foot and calf compression: a randomized controlled trial

Background

Perioperative mortality, graft failure and limitations of balloon angioplasty mitigate against active intervention for claudication. With the exception of exercise programmes, conservative treatments yield modest results. Intermittent pneumatic compression (IPC) of the foot used daily for over 3 months enhances significantly the walking ability and pressure indices of stable claudicants. This prospective randomized study evaluated the effects of IPC of the foot and calf simultaneously (IPCfoot + calf) on the walking ability, arterial haemodynamics and quality of life of patients with intermittent claudication.

Methods

Forty-one stable claudicants, meeting stringent inclusion and exclusion criteria, were randomized to receive either IPCfoot + calf and 75 mg aspirin (group 1; n = 21) or 75 mg aspirin alone (group 2; n = 20), with stratification for diabetes and smoking. Groups matched for age, sex, initial (ICD) and absolute (ACD) claudication distance, ankle: brachial pressure index (ABPI), popliteal artery flow (Q) and quality of life (Short Form (SF) 36 questionnaire). IPCfoot + calf (120 mmHg, three cycles per min, inflation 4 s, proximal inflate delay 1 s) was used for 2·5 h daily for 5 months consecutively. Both groups were advised to exercise unsupervised. Evaluation of patients, after randomization, included: (a) ICD and ACD on a treadmill, (b) resting and postexercise ABPIs, (c) Q using duplex imaging, and (d) quality of life. Study time-points were: baseline and 1, 2, 3, 4, 5 and 17 months. Compliance was assessed by means of a log book. Non-parametric statistical analysis was used (Wilcoxon and Mann–Whitney tests).

Results

After 5 months of IPCfoot + calf median ICD, ACD, resting and postexercise ABPI in group 1 increased by 197, 212, 17 and 64 per cent (all P &lt; 0·001) respectively; changes in group 2 were all non-significant (P &gt; 0·1). On intergroup comparison at 5 months, patients in group 1 were better than those in group 2 in terms of ICD, ACD, resting and postexercise ABPI (all P &lt; 0·01). Q changes within this period were not significant in either group; neither were intergroup Q differences (P &gt; 0·1). Associated changes in the quality of life within group 1 at the end of month 5 were significant; non-significant changes were noted in group 2. At 5 months patients in group 1 enjoyed a better quality of life than those in group 2 (P &lt; 0·01). IPCfoot + calf use did not result in any complications. The daily IPCfoot + calf compliance (2·5 h per day) was greater than 82 per cent in the first month and greater than 85 per cent in months 2–5. One year after the end of IPCfoot + calf application, patients in group 1 maintained the improved ABPI and walking benefit.

Conclusion

IPCfoot + calf emerged as an effective, high-compliance, uncomplicated method for improving the walking ability and pressure indices in patients with stable claudication, with a confirmed durable outcome. These changes are associated with a significant improvement in all aspects of quality of life evaluated by the SF-36. Despite a limited benefit noted in some individuals, unsupervised exercise had a non-significant impact overall.

Spectrum and prevalence of prothrombotic single nucleotide polymorphism profiles in the Greek Cypriot population

BACKGROUND

This study was performed to establish the allele, genotype and genotype combination/SNP (single nucleotide polymorphism) profile frequencies in the general population of Cyprus for 6 genes implicated in thrombotic disorders. The genes with their respective functional polymorphisms were the following: factor V (G1691A), prothrombin/factor II (G20210A), methylenetetrahydrofolate reductase (C677T), platelet glycoprotein receptor IIIa (P1A1/A2), b-fibrinogen (G/A-455) and plasminogen activator inhibitor-type 1 (4G/5G).

METHODS

DNA samples from 121 unrelated individuals were used for this epidemiological study. The polymerase chain reaction followed by restriction digestion were used to genotype the 6 different polymorphic loci. Allele and genotype frequencies were established and shown to be in Hardy-Weinberg equilibrium.

RESULTS

Mutant allele frequencies for the 6 genes were as follows: factor V-4%, prothrombin-2%, methylenetetrahydrofolate reductase -39%, platelet glycoprotein receptor IIIa-16%, beta-fibrinogen-17% and plasminogen activator inhibitor - type 1-46%. Combined defects occurred which may increase the risk for vascular events, 33% of individuals (39/118) had 3 or more of the above mutations.

CONCLUSIONS

As in other European populations, prospective case-control studies to estimate the risk for deep vein thrombosis (DVT) and ischemic episodes with respect to genetic and environmental risk factors should be performed. Thrombophilia screening should be applied for primary and secondary prevention of thrombotic episodes in susceptible individuals on the island of Cyprus. Individuals targeted for such screening include those with the following: a positive family history for thrombosis; a previous DVT or other ischemic episode; prior exposure to circumstantial risk factors and in the presence of echolucent plaques.

Association of the HLA antigens with early atheromatosis in subjects with type 2 diabetes mellitus

BACKGROUND

Inflammation plays an important role in the pathogenesis of atherosclerosis. The major histocompatibility complex, as expressed by the human leukocyte antigens (HLA) is considered to regulate the immune response. The aim of this study was to investigate the association of the HLA antigens with vascular remodeling estimated by the carotid intima-media thickness (IMT) in subjects with type 2 diabetes mellitus (DM).

METHODS

We evaluated 197 patients with type 2 DM, 80 males and 117 females, mean age 61.8+/-7.8 years, with no history of cardiovascular events. The presence of other major cardiovascular risk factors was recorded. The currently identified HLA class I (-A, -B, -Cw) and class II (DR, -DQ) antigens were studied by a classical 2 step microlymphocytotoxic technique in peripheral blood T and B lymphocytes. Measurements of the IMT were performed in the right and left common carotid arteries, 15-20 mm proximal to the dilatation of the carotid bulb in an end-diastolic "frozen" and magnified B-mode ultrasonographic image. Glycosylated hemoglobin A1c (HbA1c) and C-reactive protein (CRP) were also measured. The results are presented as mean +/-1 standard deviation.

RESULTS

Regarding the HLA phenotypes in the final analysis we tested a total of 24 HLA antigens that exhibited a frequency of at least 5% in our diabetic population. Only HLA A3 was found to be significantly associated with the carotid IMT. Forty-nine (24.9%) diabetics were HLA A3 positive (group A), while 148 (75.1%) were HLA A3 negative (group B) and had mean IMT of 0.89+/-0.16 mm and 0.98+/-0.21 mm, respectively (p<0.01). Also the two groups differed significantly in respect to CRP, with group A exhibiting lower serum levels (1.1+/-0.4 mg/dl vs 2.6+/-0.7 mg/dl for group A and B, respectively, p<0.05). However, no differences were observed between the two groups as far as blood glucose control, arterial hypertension and dyslipidaemia were concerned.

CONCLUSIONS

Human leukocyte antigen A3 is associated with less vascular damage, as expressed by carotid wall thickness, in subjects with type 2 DM. These subjects may be characterized by a milder inflammatory response, as shown by the lower serum levels of CRP.

[Treatment of severe intermittent claudication: ORACLE-PGE1 short term study. A randomised 40-week study. Evaluation of efficacy and costs]

BACKGROUND

The efficacy and cost of prostaglandin E1 (PGE1) in severe intermittent claudication was studied comparing a long-term protocol (LTP) with a short-term protocol (STP) in a randomised 40-week study.

METHODS

Phase 1 was a 2-week run-in phase (no treatment) for both protocols. In LTP, phase 2 was the main treatment phase. Treatment was performed with 2-hour infusions (60 micro g PGE1, 5 days each week for 4 weeks. In phase 3 (4-week interval period), PGE1 was administered twice a week (same dosage). In phase 4 (40 weeks), no PGE1 were used. In STP, phase 2 treatment was performed in two days by a 2-hour infusion (60 micro g PGE1 twice a day in 2 days). The same cycle was repeated every 4 weeks. A treadmill test was performed at inclusion, at the beginning of each phase and at the end of weeks 12, 16, 20 32 and 40. A progressive training plan (walking) and reduction in risk factors plan was used in both groups.

RESULTS

Out of the 1276 included patients 1165 completed the study (606 in LTP group; 559 in the STP). Drop-outs were 111. The two groups were comparable in distribution, risk factors and smoking. Intention-to-treat analysis indicated an increase in pain free walking distance (PFWD). The absolute and percent increase in pain-free walking distance (PFWD) was comparable in both LTP and STP groups with a significative increase in TWD at 4 weeks. At 20 and 40 weeks increase was up to 219% in the LTP and 460% in the STP group (p<0.02). Comparable results concerning PFWD were obtained in the two groups. Both treatments were well tolerated. No side effect was observed. Local effects were observed in 8.5% of the treated subjects in the LTP and 4% in the STP. The average cost of the LTP protocol was 8786 Euro. For STP the costs was 946 (10.8% of LTP). For both protocols the cost of the infusion was 24% of the total for the LTP and 35% in the STP. Therefore 75% of the cost is not drug-related.

CONCLUSIONS

In conclusion between-group-analysis favours STP considering walking distance and costs. Results indicate good efficacy and tolerability of PGE1 treatment particularly STP.

Platelet activation during carotid endarterectomy and the antiplatelet effect of Dextran 40

OBJECTIVE

To determine changes in platelet activation during carotid endarterectomy (CEA) and the antiplatelet effect of Dextran 40.

METHODS

Prospective study in 40 patients undergoing CEA. Platelet activity was measured by whole blood flow cytometry and platelet aggregometry during CEA. The expression of P-selectin and the PAC-1 antigen were used as markers of platelet activation and aggregation. Patients received aspirin (75-300 mg) preoperatively and 5,000 units unfractionated heparin during surgery. High intensity transient signals (HITS) in the ipsilateral middle cerebral artery were monitored using transcranial Doppler (TCD) perioperatively.

RESULTS

P-selectin expression increased after carotid clamping (P < 0.01) and clamp release (P < 0.05). There was higher expression of PAC-1 after carotid clamping (p < 0.05). Spontaneous and ADP-induced platelet aggregation increased after carotid clamping (P< 0.01) and release (P < 0.01). TCD monitoring showed an increased HITS count from preoperative levels, after clamp release (P < 0.01) and during recovery (P < 0.01). After the operation, patients with more than 50 HITS per 30 min were started on an infusion of dextran 40 (n = 6). P-selectin expression decreased 24 h after dextran 40 (P < 0.01).

CONCLUSION

Significant platelet activation and aggregation occurs during CEA despite the current use of antiplatelet treatment. Dextran 40 had an antiplatelet effect after CEA providing further evidence that it may contribute to reducing thromboembolic complications.

Out of a recent CVI consensus: some features of a basic statement

In March 1997 at the Abbaye des Vaux de Cernay, France, a multidisciplinary meeting of venous specialists, to do guidelines on venous management was held. Subsequently the faculty members revised the document and a consensus statement was published in Circulation, in November 2000, based on wide-ranging and authoritative research into the investigation of chronic venous insufficiency (CVI). The statement gives information on the epidemiology and pathophysiology of CVI including the changes in the major veins as well as in the microcirculation and the associated hematological changes. It sets out the methods used for morphologic and hemodynamic investigations into venous disease and for the study of the microcirculation stating their usefulness and limitations, and indicating their place in clinical practice and research. A section deals also with the rare venous malformations. It concludes with an application of the methods in the investigation on CVI based on the CEAP classification that gives a uniform way of reporting venous disorders. The document is intended both for the clinician and the researcher. A shortened version appears below.

'Real' epidemiology of varicose veins and chronic venous diseases: the San Valentino Vascular Screening Project

The aim of this study was to evaluate the prevalence and incidence of venous diseases and the role of concomitant/risk factors for varicose veins (VV) or chronic venous insufficiency (CVI). The study was based in San Valentino in Central Italy and was a real whole-population study. The study included 30,000 subjects in eight villages/towns evaluated with clinical assessment and duplex scanning. The global prevalence of VV was 7%; for CVI, the prevalence was 0.86% with 0.48% of ulcers. Incidence (new cases per year) was 0.22% for VV and 0.18% for CVI; 34% of patients with venous disease had never been seen or evaluated. The distribution of VV and CVI in comparison with duplex-detected incompetence (DI) indicates that 12% of subjects had only VV (no DI), 2% had DI but no VV, 7.5% had DI associated with VV, 2% apparent CVI without DI, 3% DI only (without CVI), and 1.6% both CVI and DI. VV associated with DI are rapidly progressive and CVI associated with DI often progresses to ulceration (22% in 6 years). VV without significant DI (3%) and venous dilatation without DI tend to remain at the same stage without progression for a lengthy time. New cases per year appear to have a greater increase in the working population (particularly CVI) possibly as a consequence of trauma during the working period. In older age (>80 years), the incidence of CVI tends to decrease. Ulcers increase in number with age. Only 22% of ulcers can be defined as venous (due to venous hypertension, increased ambulatory venous pressure, shorter refilling time, obstruction and DI). Medical advice for VV or CVI is requested in 164 subjects of 1,000 in the population. In 39 of 1,000, there is a problem but no medical advice is requested and in only 61 of 1,000, the venous problem is real. In VV in 78% of limbs, there is only reflux, in 8% only obstruction, and in 14% both. In CVI, 58% of limbs have reflux, 23% obstruction, and 19% both. In conclusion, VV and CVI are more common with increasing age. The increase with age is linear. There was no important difference between males and females. These results are the basis for future real, whole population studies to evaluate VV and CVI.

Treatment of venous ulcers with pentoxifylline: a 12-month, double-blind, placebo controlled trial. Microcirculation and healing

The aim of this study was the evaluation of the treatment of venous ulcers with pentoxifylline (PXF) in 12 months. This double-blind, placebo-controlled trial was conducted in GCP. Patients were included after consent and randomized for PXF (400 mg three times daily) or placebo. The number of healed ulcers, the variation in the area of ulceration, and the variation in microcirculatory parameters (laser-Doppler flux and skin PO2) were considered as endpoints. Of the 85 patients included, 80 completed the study (41 in the PXF and 39 in the placebo group). The groups were comparable. Healing occurred in 88% of limbs in the PXF and in 44% in the placebo group (44% difference; p<0.02). The average area reduction was 93% in the PXF and 56% in the placebo group. Microcirculation was significantly improved in both groups at 12 months. The decrease in flux and the increase in PO2 were greater in the PXF group (p<0.05). Considering the proportion of healed ulcers a better outcome was observed with PXF (p<0.02; 12% of nonhealed ulcers in the PXF vs 56% in the placebo group). The ulcerated area decreased 93% in the PXF vs 56% in the placebo group (40% difference; p<0.02). Tolerability was comparable (6% in the PXF group and 5% in the placebo group complained for treatment). No important side effects were observed. In conclusion, treatment with PXF in venous ulcers improves healing and microcirculation and should be considered in slow-healing venous ulcers.

Treatment of severe intermittent claudication with pentoxifylline: a 40-week, controlled, randomized trial

The efficacy, safety, and cost of pentoxifylline (PXF) in the treatment of severe intermittent claudication were studied comparing PXF and placebo in a randomized 40-week study. A treadmill test was performed at inclusion and at the end of weeks 20 and 40. A progressive training plan and the control of risk factors (with antiplatelet treatment) were used in both groups. Of the 200 included patients, 178 completed the study: 88 in the PXF group and 90 in the placebo group. There were 22 dropouts. The two groups were comparable for age, sex distribution, and for the presence of risk factors and smoking. There was a significant increase in pain-free walking distance (PFWD) in both groups. The absolute and percent increase in PFWD was significantly greater in the PXF group (p<0.05). At 20 weeks, the increase was 360.5% in the PXF vs 252% in the placebo group. At 40 weeks, the increase was 386% in the PXF and 369% in the placebo group (p<0.02). Total walking distance (TWD) increased at 20 weeks (up to 254%) and up to 329% at 40 weeks. In the placebo groups the increase was 158% at 20 weeks and 183% at 40 weeks. The excess increase produced by PXF treatment was 30% at 20 weeks and 38% at 40 weeks (p<0.02). Unwanted effects treatment was well tolerated. No serious drug-related side effects were observed. In summary, between-group analysis favors PXF considering walking distance and costs. Results indicate good efficacy and tolerability.

Treatment of vascular inner ear disease in vascular patients with pentoxifylline: a controlled, randomized trial

The efficacy of Pentoxifylline in vascular inner ear disease (VIED) was studied comparing PXF and placebo in a 4-week study; 40 patients with vascular disease and monolateral loss of hearing, vertigo, dizziness, tinnitus (analyzed with an analogue scale line), and cochlear flow reduction were included. The aims of the study were to study the effects of PXF (1600 mg daily) in VIED considering clinical outcome and cochlear flow. Of the 20 included patients, 19 completed the study. One dropout in the placebo group was due to low compliance. Intention-to-treat analysis indicated an improvement in cochlear flow (p<0.05) and a decrease in score in both groups. The cochlear flow increase was 287.5% in the PXF group vs 168% in the placebo group (119.5% difference; p<0.02). There was a difference in score decrease (44.1% larger) in the PXF group (p<0.05).Between-group analysis favors PXF considering blood flow and symptoms. Results indicate good efficacy and tolerability of PXF in VIED.

Treatment of vascular retinal disease with pentoxifylline: a controlled, randomized trial

The aim of this study was to evaluate the effect of PXF (1800 mg daily) in patients with sudden loss of vision (SLV) in a 4-week trial, evaluating clinical outcome and retinal flow parameters. Inclusion criteria were SLV associated with thrombosis of the retinal artery; decrease in retinal blood flow (PSF: peak-systolic flow; EDF: end-diastolic flow velocity) and asymmetry between the two retinal arteries (>40%) documented by duplex scanning. All 10 included patients completed the study. The groups were comparable. No side effects were reported. A significant improvement in flow velocity (p<0.05) and a decrease in analogue score in both groups were observed. PSF increase was 550% in the PXF group vs 288% in the placebo group (262% difference). EDF increase was 400% in the PXF group vs 200% in the placebo group (200% difference). There was a significant difference in the analogue score decrease (33.3% difference larger in the PXF group; p<0.05). In conclusion, PXF treatment improved retinal flow after retinal artery occlusion better than placebo and should be considered as an important option in this condition.

Treatment of long-distance intermittent claudication with pentoxifylline: a 12-month, randomized trial

The efficacy, safety, and cost of pentoxifylline (PXF) in long-range (>400 m interval) intermittent claudication was studied comparing PXF and placebo in a 12-month study. A standardized treadmill test was performed at inclusion and at 6 and 12 months. A training plan based on walking was associated with the control of risk factor levels. Of the 194 included patients, 135 completed the study: 75 in the PXF group and 60 in the placebo group. There were 59 dropouts (due to low compliance). The authors observed a 148% increase in total walking distance (TWD) at 6 months with PXF (vs 110% with placebo; p<0.05); at 12 months, the increase was 170% with PXF (vs 131% with placebo; p<0.02). There was a 38% difference at 6 months and 39% at 12 months in favor of PXF. Treatment was well tolerated. In conclusion, PXF improved walking distance significantly better than placebo.

Short-range intermittent claudication and rest pain: microcirculatory effects of pentoxifylline in a randomized, controlled trial

The efficacy of pentoxifylline (PXF) in severe intermittent claudication was studied comparing PXF and placebo. Patients were randomized into two treatment plans: PXF (2400 mg, four 600-mg tablets daily) or equivalent placebo was administered for 10 days. The exercise protocol associated with treatment was conducted under supervision. Skin flux (RF) was measured at rest and after 1 minute of exercise (AEF = after exercise flux; 3 km/hr, 12% inclination) with laser Doppler. PO2 and PCO2 were measured at the dorsum of the foot. All 20 included patients completed the study. The two groups were comparable. In the PXF group there was a significant increase in RF, AEF, and in PO2 (p<0.05); PCO2 was decreased (p<0.05). There were also changes in the placebo group, significantly lower than those observed in the PXF group (p<0.05). In conclusion high-dose PXF treatments improved all microcirculatory parameters in subjects with short-range claudication even with a short period of treatment.

Treatment of intermittent claudication with pentoxifylline: a 12-month, randomized trial--walking distance and microcirculation

The efficacy, safety and cost of pentoxifylline (PXF) in severe intermittent claudication was studied comparing PXF and placebo in a 12-month study. A treadmill test and microcirculatory evaluation with laser Doppler flowmetry were performed at inclusion and at the end of 6 and 12 months. A physical training plan (based on walking) and reduction in risk factor levels plan was used in both groups. Of the 120 included patients, 101 completed the study: 56 in the PXF group and 45 in the placebo group. There were 19 dropouts (due to low compliance). The two groups were comparable for age, sex distribution, walking distance, and the presence of risk factors and smoking. Intention-to-treat analysis indicated a 268% increase in walking distance in the PXF group (vs 198% in the placebo group; p<0.05) at 6 months and an increase of 404% (vs 280% in the placebo group; p<0.02) at 12 months. The absolute and percent increase in pain-free walking distance (PFWD) was greater in the PXF group (p<0.05). Treatment was well tolerated. No serious drug-related side effects were observed. Microcirculatory evaluation indicated an increase in flux (p < 0.05) in the PXF group (not significant in the placebo group); the after-exercise flux (AEF) was increased (p<0.05) in both groups at 6 months but the increase in AEF was greater in the PXF group at 12 month. In conclusion, between-group analysis favors PXF considering walking distance and microcirculatory parameters. Results indicate good efficacy and tolerability.

Treatment of venous ulcers with pentoxifylline: a 6-month randomized, double-blind, placebo controlled trial

The aim of this study was the evaluation of treatment with pentoxifylline in patients with venous ulcers in a 6-month, randomized, controlled trial. Treatment with placebo or pentoxifylline (PXF; 400 mg, 3 times daily) lasted 6 months and was associated to elastic bandaging. The endpoints were the number of limbs with complete healing and the variation in the area of ulceration. A group of 172 patients were included: 82 in the PXF group and 88 in the placebo group; 82 completed the study in the PXF group and 78 in the placebo group. Results. The two groups were comparable for age and sex distribution. The treatment was well tolerated. Complete healing was obtained in 67% of patients in the PXF group and 30.7% in the placebo group (p<0.02). The variations in the average area of ulceration were 86.7% (decrease) in the PXF group and 47% in the placebo group. The cost of treatment increased 21% with PXF but the cost due to non-healing of the ulcer was equivalent to a 44% increase (in comparison with the PXF group). In conclusion PXF is effective and cost-effective in improving ulcer healing in patients with chronic venous hypertension.

Treatment of retinal vein thrombosis with pentoxifylline: a controlled, randomized trial

The aim of this study was to evaluate PXF (pentoxifylline; 1600 mg daily vs placebo) in patients with retinal vein thrombosis (RVT) in a 4-week trial, evaluating clinical outcome and retinal flow. Inclusion criteria were sudden loss of vision (SLV); retinal vein thrombosis (RVT); decrease in retinal vein flow; asymmetry between retinal veins (>40%) documented by duplex scanning (retinal vein thrombosis flow = RVTF). All 18 included patients completed the study. The groups were comparable. No side effect was observed. An improvement in arterial flow (p<0.05) and a decrease in analogue score (p<0.05) were observed in both groups (due to the spontaneous evolution with partial thrombus lysis in 4 weeks). The increase in arterial flow (PSF and EDF) were greater (p<0.05) in the PXF group. The RVFV increase was better in the PXF group (350% increase vs 200% increase in the placebo group; p<0.05). There was a significant difference in the analogue score decrease (4 vs 7) in the PXF group (p<0.05). In conclusion, PXF improved retinal flow after RVT better than placebo. It should be considered as an important treatment option.

Treatment of vascular inner ear disease with pentoxifylline: a 4-week, controlled, randomized trial

The efficacy of pentoxifylline (PXF) in vascular inner ear disease (VIED) was studied comparing PXF and placebo in a 4-week study; 60 patients with unilateral loss of hearing, vertigo, dizziness, tinnitus (analyzed with an analogue scale line), and cochlear flow reduction were included. The aim of the study was to study the effect of PXF (1800 mg/day) in VIED considering clinical outcome and cochlear flow. All patients completed the study. Improvement in cochlear flow (p<0.05) and a decrease in score in both groups were observed. The cochlear flow increase was 287.5% in the PXF group vs 168% in the placebo group (119.5% difference; p<0.02). There was a difference in score decrease (44.1% larger) in the PXF group (p<0.05). PXF was more effective considering flow and symptoms.

Intermittent claudication in diabetics: treatment with exercise and pentoxifylline--a 6-month, controlled, randomized trial

The aims of this study were to evaluate the effect of PXF (1600 mg daily) in diabetic patients with intermittent claudication. Of the 60 included patients, 53 completed the study (27 in the PXF group). There were seven dropouts. The groups were comparable for age, sex distribution, and total walking distance (TWD), and risk factors. There was an increase in TWD at 3 and 6 months in both groups (p<0.05) possibly due to exercise. However the increase (both absolute and percentage) in TWD was significantly larger in the PXF group. At 6 months, PXF produced a 292% increase in TWD (vs 180% produced by placebo) (p<0.02). The excess increase produced by PXF treatment was 112% at 6 months in comparison with placebo (p<0.02). Treatment was well tolerated. Between-group analysis favors PXF considering TWD, and results indicate good efficacy and tolerability.