Compression treatment in acute symptomatic proximal deep venous thrombosis - Results of a worldwide survey

OBJECTIVES

The aim of this study was to illustrate how compression is performed worldwide in proximal DVT and if compression management has changed recently.

METHODS

A global online survey, consisting of 36 questions, was used. The survey was solicited from membership lists of Union Internationale de Phlébologie (UIP) membership societies. For differences between the continents in comparison to Western Europe odds ratios and 95% Confidence Intervals (95%CI) where calculated.

RESULTS

We received 626 answers from 41 countries. Compression is routinely used in proximal DVT in all regions (82.8%). 81.4% start compression immediately after diagnosis. In the acute phase of DVT reduction of pain and swelling (91.7%) and PTS prevention (66.2%) are the main reasons for compression. 33.2% recently changed their compression management with 43.5% starting compression earlier and 7.0% later.

CONCLUSIONS

Compression is still used routinely in proximal DVT in addition to anticoagulation. The changes in international guidelines towards the non-routine use of compression in proximal DVT have not caused significant changes in DVT management.

A randomized cross-over trial in patients suspected of PAD on diagnostic accuracy of ankle-brachial index by Doppler-based versus four-point oscillometry based measurements

Summary. Background: For diagnosis of peripheral arterial occlusive disease (PAD), a Doppler-based ankle-brachial-index (dABI) is recommended as the first non-invasive measurement. Due to limitations of dABI, oscillometry might be used as an alternative. The aim of our study was to investigate whether a semi-automatic, four-point oscillometric device provides comparable diagnostic accuracy. Furthermore, time requirements and patient preferences were evaluated. Patients and methods: 286 patients were recruited for the study; 140 without and 146 with PAD. The Doppler-based (dABI) and oscillometric (oABI and pulse wave index – PWI) measurements were performed on the same day in a randomized cross-over design. Specificity and sensitivity against verified PAD diagnosis were computed and compared by McNemar tests. ROC analyses were performed and areas under the curve were compared by non-parametric methods. Results: oABI had significantly lower sensitivity (65.8%, 95% CI: 59.2%–71.9%) compared to dABI (87.3%, CI: 81.9–91.3%) but significantly higher specificity (79.7%, 74.7–83.9% vs. 67.0%, 61.3–72.2%). PWI had a comparable sensitivity to dABI. The combination of oABI and PWI had the highest sensitivity (88.8%, 85.7–91.4%). ROC analysis revealed that PWI had the largest area under the curve, but no significant differences between oABI and dABI were observed. Time requirement for oABI was significantly shorter by about 5 min and significantly more patients would prefer oABI for future testing. Conclusions: Semi-automatic oABI measurements using the AngER-device provide comparable diagnostic results to the conventional Doppler method while PWI performed best. The time saved by oscillometry could be important, especially in high volume centers and epidemiologic studies.

Prospective Evaluation of the TIGRIS Vascular Stent Within a Modern Treatment Algorithm

Purpose: To prospectively evaluate the safety and efficacy of the TIGRIS Vascular Stent in the superficial femoral artery (SFA) and proximal popliteal artery within a treatment algorithm that reserved stent usage for more challenging patients. Materials and Methods: This prospective, single-center study enrolled 97 patients (mean age 68.7 years; 66 men) who were treated for 100 de novo or nonstented restenotic femoropopliteal lesions (≥70% stenosis) and had recoil or dissection after plain balloon predilation. The average lesion length was 5.6±2.3 cm (maximum 8 cm per protocol). The composite primary efficacy outcome was 12-month primary patency, defined as a peak systolic velocity ratio ≤2.5 at the stented target lesion on duplex ultrasound, and no clinically-driven reintervention within the stented segment. The primary safety outcome was freedom from device- and procedure-related target vessel revascularization, target limb major amputation (above the metatarsals), or death through 30 days. Secondary outcomes included secondary patency, clinically-driven target lesion revascularization (TLR), Rutherford category change relative to baseline, and binary restenosis of the target lesion. Results: All devices were successfully implanted with no device-related complications at the time of implant or within the 30-day postimplant window. The average stented length was 7.0±2.5 cm; no stent elongation was observed during deployment. One patient was lost to follow-up before 12 months and another died of an unrelated cause, leaving 95 patients (98 lesions) available for 12-month follow-up and 77 patients/lesions for the 24-month preliminary analysis. The binary primary and secondary patency rates at 12 months were 92.9% and 100%. The binary freedom from TLR was 94.9%. At 24 months, the Kaplan-Meier estimate of primary patency was 90.0%. Conclusion: This prospective study demonstrated that the TIGRIS Vascular Stent is a safe and effective device in a modern treatment algorithm that reserved bare stent use for postangioplasty dissection or recoil in distal femoropopliteal arteries.

Safety and efficacy of direct acting oral anticoagulants and vitamin K antagonists in nonvalvular atrial fibrillation – a network meta-analysis of real-world data

Abstract. Background: In randomized controlled trials (RCTs) direct acting oral anticoagulants (DOACs) showed a superior risk-benefit profile in comparison to vitamin K antagonists (VKAs) for patients with nonvalvular atrial fibrillation. Patients enrolled in such studies do not necessarily reflect the whole target population treated in real-world practice. Materials and methods: By a systematic literature search, 88 studies including 3,351,628 patients providing over 2.9 million patient-years of follow-up were identified. Hazard ratios and event-rates for the main efficacy and safety outcomes were extracted and the results for DOACs and VKAs combined by network meta-analysis. In addition, meta-regression was performed to identify factors responsible for heterogeneity across studies. Results: For stroke and systemic embolism as well as for major bleeding and intracranial bleeding real-world studies gave virtually the same result as RCTs with higher efficacy and lower major bleeding risk (for dabigatran and apixaban) and lower risk of intracranial bleeding (all DOACs) compared to VKAs. Results for gastrointestinal bleeding were consistently better for DOACs and hazard ratios of myocardial infarction were significantly lower in real-world for dabigatran and apixaban compared to RCTs. By a ranking analysis we found that apixaban is the safest anticoagulant drug, while rivaroxaban closely followed by dabigatran are the most efficacious. Risk of bias and heterogeneity was assessed and had little impact on the overall results. Analysis of effect modification could guide the clinical decision as no single DOAC was superior/inferior to the others under all conditions. Conclusions: DOACs were at least as efficacious as VKAs. In terms of safety endpoints, DOACs performed better under real-world conditions than in RCTs. The current real-world data showed that differences in efficacy and safety, despite generally low event rates, exist between DOACs. Knowledge about these differences in performance can contribute to a more personalized medicine.

Levels of Prothrombin Fragment F1+2 in Patients with Hyperhomocysteinemia and a History of Venous Thromboembolism

Increased thrombin generation occurs in many individuals with inherited defects in the antithrombin or protein C anticoagulant pathways and is also seen in patients with thrombosis without a defined clotting abnormality. Hyperhomocysteinemia (H-HC) is an important risk factor of venous thromboembolism (VTE). We prospectively followed 48 patients with H-HC (median age 62 years, range 26-83; 18 males) and 183 patients (median age 50 years, range 18-85; 83 males) without H-HC for a period of up to one year. Prothrombin fragment Fl+2 (Fl+2) was determined in the patient’s plasma as a measure of thrombin generation during and at several time points after discontinuation of secondary thromboprophylaxis with oral anticoagulants. While on anticoagulants, patients with H-HC had significantly higher Fl+2 levels than patients without H-HC (mean 0.52 ± 0.49 nmol/1, median 0.4, range 0.2-2.8, versus 0.36 ± 0.2 nmol/1, median 0.3, range 0.1-2.1; p = 0.02). Three weeks and 3,6,9 and 12 months after discontinuation of oral anticoagulants, up to 20% of the patients with H-HC and 5 to 6% without H-HC had higher Fl+2 levels than a corresponding age- and sex-matched control group. 16% of the patients with H-HC and 4% of the patients without H-HC had either Fl+2 levels above the upper limit of normal controls at least at 2 occasions or (an) elevated Fl+2 level(s) followed by recurrent VTE. No statistical significant difference in the Fl+2 levels was seen between patients with and without H-HC. We conclude that a permanent hemostatic system activation is detectable in a proportion of patients with H-HC after discontinuation of oral anticoagulant therapy following VTE. Furthermore, secondary thromboprophylaxis with conventional doses of oral anticoagulants may not be sufficient to suppress hemostatic system activation in patients with H-HC.

The Risk of Recurrent Venous Thromboembolism in Patients with and without Factor V Leiden

Thromboprophylaxis with oral anticoagulants up to six months is established in patients after a first venous thromboembolic event (VTE). The risk of recurrent VTE is still considerable thereafter, and it is uncertain whether some patients might benefit from extended anticoagulation. We performed a prospective, multicenter trial (4 thrombosis centers) and evaluated in 380 patients with a first or recurrent VTE (patients with a deficiency of antithrombin, protein C, protein S or plasminogen; cancer; or an antiphospholipid antibody syndrome were excluded) the risk of recurrence after discontinuation of secondary thromboprophylaxis with oral anticoagulants. It was the aim of the study to evaluate whether patients with factor V Leiden are at an increased risk of recurrent VTE. 112 (29.5%) patients were carriers of factor V Leiden (26.9% heterozygous, 2.6% homozygous). After a median observation time of 19.3 months the overall recurrence rate of VTE was 9.9%. Recurrent deep vein thrombosis and/or pulmonary embolism occurred in 26 of 268 patients without factor V Leiden (9.7%) and in 10 of 112 patients with factor V Leiden (8.9%). The probability of recurrent VTE two years after discontinuation of oral anticoagulants was 12.4% (95% Cl 7.8-17) in patients without factor V Leiden and was 10.6% (95% Cl 3.8-17.4) in carriers of the mutation. This difference was statistically not significant. Patients with factor V Leiden are not at a higher risk of recurrent VTE within two years after discontinuation of oral anticoagulants than patients without factor V Leiden. Balancing the risk of recurrent VTE and bleeding from oral. anticoagulants, patients with factor V Leiden are not likely to benefit from oral anticoagulant therapy extended beyond six months.

Prothrombin Fragment F1+2 Is not Predictive for Recurrent Venous Thromboembolism

It would be important to estimate in advance the risk of recurrent thrombosis. Deficiencies of antithrombin, protein C or protein S, or resistance to activated protein C are associated with a biochemically detectable prethrombotic state. It is thus far unknown whether in patients with a history of thromboembolism but without a defined clotting abnormality a heightened coagulation activation is detectable.

We investigated the value of prothrombin fragment Fl+2 (FI+2) as a predictor of recurrent venous thromboembolism. Furthermore, we compared the Fl+2 levels of thrombosis patients without a defined clotting defect to those of Factor V Leiden patients with a history of venous thrombosis and to those of healthy controls. 180 patients without a defined clotting abnormality and 73 patients with Factor V Leiden were prospectively followed after discontinuation of oral anticoagulants for venous thrombosis and Fl+2 was measured at regular intervals.

Recurrent venous thromboembolism occurred in 23 (9%) of the 253 patients. Before or at several time points after oral anticoagulants, no significant difference in Fl+2 levels was found in patients with and without recurrent thrombosis. Fl+2 levels at 3 weeks and prior to recurrence were not significantly different in both patient groups. Over a one-year observation period, Fl+2 levels of both patients with and without Factor V Leiden were higher than those of the controls. No difference in Fl+2 was seen between patients with and without Factor V Leiden.

We conclude that monitoring of Fl+2 is not suitable for identification of individuals at risk of recurrent venous thrombosis. Permanent hemostatic system activation is detectable both in patients with a defined abnormality of the clotting system and in patients in whom a particular defect has not (yet) been identified.

Pathogenesis of chronic venous insufficiency by obesity

Obesity (body mass index: BMI ≥30 kg/m2) is named as a risk factor for chronic venous insufficiency (CVI) in phlebologic studies, even though the mechanisms of effects are still unclear. Therefore we examined literature for current data and hypotheses and described them.

On the one hand, the correlation between obesity and CVI is explained by chronically inflammatory processes, affected by the lipometabolism of obese and the metabolic syndrome. On the other hand, this particular correlation is explained by a mechanical approach based on an elevated intraabdominal pressure (IAP), which is transmitted to the venous system of the lower extremities. Recent studies show that the chronically inflammatory processes promote the frequency and manifestation of thrombosis. In regard to the IAP, only the pressure of the elevated abdominal mass (paunch) seems to have a minimal effect in the supine position.

Several studies relativised the correlation between obesity and CVI because of the rising prevalence of venous disease with age, which correlates with a higher BMI as well. Furthermore, studies have shown the phenomena of so-called venous hydrostatic ulcerations in obese patients. That means those patients show the typical skin changes of the CVI without any venous reflux. Depending on the study, their proportion is estimated between 21% and 64% of venous leg ulcers. Additionally, it was shown that after weight loss the skin seems to regenerate from the typical signs of CVI. At the moment, the pathomechanism causing hydrostatic ulcers in obese is unclear.

Basal high-sensitivity-C-reactive protein levels in patients with spontaneous venous thromboembolism

The role of C-reactive protein (CRP) in venous thromboembolism (VTE) is still under discussion because of controversial results in the literature. Conflicting data may have partly been due to bias by exogenous factors altering CRP levels. We investigated CRP concentrations in patients with spontaneous VTE applying a study design that allowed the measurement of basal high sensitivity (hs)-CRP levels. Patients with a history of deep vein thrombosis (DVT, n=117) and pulmonary embolism (PE, n=97) were compared to healthy individuals (n=104). Hs-CRP levels (mg/dl) were significantly higher in patients (n=214, median/interquartile range: 0.171/0.082–0.366) than in controls (0.099/0.053–0.245, p=0.001). The unadjusted odds ratio (OR) for VTE per 1 mg/dl increase of CRP was 2.8 [95% confidence interval (CI): 1.1–6.8, p=0.03]. This association remained significant after adjustment for factor V Leiden, prothrombin G20210A and factor VIII activity above 230% (OR = 2.9, 95% CI [1.1–7.5]), but became remarkably attenuated and lost its statistical significance after adjustment for BMI alone (OR = 1.7 [0.7–4.0]). CRP was also not independently associated with VTE in subgroups of patients (those with DVT without symptomatic PE, those with PE and patients without established risk factor) in multiple regression analysis. In summary, we observed significantly higher basal hs-CRP levels in patients with spontaneous VTE compared to healthy controls. This association was independent of hereditary and laboratory risk factors for VTE, but lost its significance after adjustment for BMI. Increased basal CRP levels do not appear to represent an independent risk factor for VTE.

The Risk of Early Recurrent Venous Thromboembolism after Oral Anticoagulant Therapy in Patients with the G20210A Transition in the Prothrombin Gene

A G20210A transition in the prothrombin gene is a common risk factor of venous thrombosis. The risk of recurrent venous thrombo-embolism in carriers of the 20210A allele is unknown and guidelines for secondary thromboprophylaxis in these patients are not available.

In a prospective multicenter trial, 492 patients with a history of objectively documented venous thromboembolism were followed for a mean observation time of 24 ± 16 months after discontinuation of oral anticoagulants. Forty-two patients (8.5%) were carriers of the 20210A allele. Three of the 42 patients with the G20210A mutation (7%) and 54 of 450 patients without the mutation (12%) experienced recurrent venous thrombosis. At 24 months, the probability of recurrence was 8% (95% CI 0-16.7) in patients with the mutation and was 12.2% (95% CI 8.8-15.6) in patients without the mutation.

In conclusion, the risk of early recurrent venous thromboembolism is not higher in patients with the G20210A mutation than in those without the mutation. Therefore, long-term secondary thromboprophylaxis with oral anticoagulants in heterozygous carriers of the 20210A allele is not justified.

Interleukin-6 and interleukin-6 promoter polymorphism (−174) G>C in patients with spontaneous venous thromboembolism

Increased levels of interleukin-6 (IL-6) have been reported in patients with a history of venous thromboembolism (VTE); however, prospective studies did not confirm an association between inflammatory markers that are highly correlated with IL-6 and the risk of VTE. It was the aim of our study to investigate the association of IL-6 and its promoter polymorphism (−174) G>C with the risk of spontaneous VTE. IL-6 was measured in 128 patients with deep venous thrombosis (DVT, 70 w / 58 m),105 with pulmonary embolism (PE, 58w/ 47 m) and 122 healthy controls (60 w / 62 m) with a highly sensitive ELISA (Quantikine− HS Human IL-6 Immunoassay, RnDSystems®). The promoter polymorphism was determined by genotyping, allele specific PCR was followed by high resolution gel-electrophoresis. Median concentrations [interquartile ranges] were 2.37 [1.51–3.89] (pg/ ml) in patients with DVT, 2.83 [1.83–4.87] in those with PE and 2.51 [1.71–4.78] in controls (p = 0.6, p = 0.4). Hetero- or homozygous carriers of the C allele (71% in DVT, 67% in PE and 59% among controls) did not have higher IL-6 levels than homozygous carriers of the G allele (median 2.60 vs. 2.59 pg/ml, p = 0.7). In conclusion, we found no association of IL-6 and its promoter polymorphism (−174) G>C with the risk of spontaneous VTE.

Prediction of recurrent venous thromboembolism by measuring ProC Global

In patients with venous thromboembolism (VTE) a laboratory assay that globally measures the overall thrombophilic tendency is not available. We hypothesized that determination of ProC® Global, a plasma assay which tests the global function of the protein C pathway, could be used to stratify patients according to their risk of recurrent VTE. We prospectively followed 774 patients with first spontaneous VTE for a mean time of 52 months. ProC Global normalized ratio (NR) was measured in plasma by use of a commercially available assay based on activated partial thromboplastin time. Ninety-eight of the 774 patients had recurrent VTE. Patients with ProC Global NR ≥ 0.75 had a relative risk of recurrence of 0.59 (95% CI 0.40–0.87) as compared with those with lower ratio. After four years, cumulative probability of recurrence was 8.6% in patients with ProC Global NR ≥ 0.75 and 17.4% in patients with a lower ratio (p=0.006). Patients with a high ProC Global NR have a low risk of recurrent VTE. ProC Global NR can be used to stratify patients with a first unprovoked VTE according to their risk of recurrence.

Efficacy and Tolerability of Liposomal Heparin Spraygel as an Add-on Treatment in the Management of Superficial Venous Thrombosis

Superficial venous thrombosis usually resolves spontaneously in a few weeks. In most cases, treatment includes peroral analgesics or nonsteroidal anti-inflammatory drugs accompanied by the recommendation to wear elastic stockings and perform regular mild ambulation. In contrast to this “standard treatment,” a recent ACCP guideline has recommended that patients affected by spontaneous superficial thrombophlebitis be treated with intermediate doses of unfractionated or low-molecular-weight heparin. This study was designed to assess the efficacy of topically applied heparin spraygel in terms of reduction of local symptoms and signs of superficial venous thrombosis.

The long-term recurrence risk of patients with unprovoked venous thromboembolism: an observational cohort study

Essentials Long-term recurrence risk of venous thromboembolism (VTE) is uncertain. We performed a prospective cohort study of 839 patients with first unprovoked VTE. VTE recurrence risk is high, particularly in men with proximal thrombosis or pulmonary embolism. Sex and VTE site determine the recurrence risk and should be considered for patient counseling.

SUMMARY

Background The long-term recurrence risk (ltRR) of venous thromboembolism (VTE) is uncertain. Objective To assess the ltRR of patients with first unprovoked VTE. Patients/methods Patients were classified into three categories: distal deep vein thrombosis (DVT), proximal DVT or pulmonary embolism (PE), that is, PE associated with DVT or isolated PE. Patients with major thrombophilia or antithrombotic therapy were excluded. The endpoint was recurrent symptomatic VTE. Results A total of 839 patients were followed for a median of 7.7 years. VTE recurred in 263 patients (31%). After 10 and 20 years, the cumulative ltRR was 32% (95% confidence interval [CI], 29-36) and 44% (95% CI, 38-49) with 3.9 (95% CI, 3.3-4.6) and 3.3 (95% CI, 2.7-4.0) events per 100 patient-years, respectively. The adjusted hazard ratio was 2.1 (95% CI, 1.4-3.2) and 2.1 (95% CI, 1.4-3.2) for patients with proximal DVT or PE compared with patients with distal DVT and was 2.1 (95% CI, 1.6-2.9) for men compared with women. At 10 years, 4.7 (95% CI, 3.8-5.8) events per 100 patient-years occurred in men with proximal DVT or PE, 2.4 (95% CI, 1.2-4.4) in men with distal DVT, 1.9 (95% CI, 1.2-2.8) in women with proximal DVT or PE and 0.9 (95% CI, 0.2-1.9) in women with distal DVT. Conclusion The ltRR of patients with first unprovoked VTE is high and dependent upon sex and VTE site.

Life-threatening acute pneumonitis in mixed connective tissue disease: a case report and literature review

Mixed connective tissue disease (MCTD) is a rare connective tissue disease frequently involving the lungs. The main characteristic is a systemic sclerosis-like picture of slowly progressing interstitial lung disease consistent with lung fibrosis, while pulmonary arterial hypertension is rare. Herein, we present a case of a newly diagnosed MCTD patient developing life-threatening acute pneumonitis similar to lupus pneumonitis. Previous literature on this exceptionally rare complication of MCTD is reviewed and differential diagnosis and management discussed.

New oral anticoagulants in the treatment of acute venous thromboembolism - a systematic review with indirect comparisons

BACKGROUND

For decades, heparins and vitamin K antagonists (VKAs) have been the gold standards in therapy of venous thromboembolism (VTE). The advent of factor IIa and Xa inhibitors provides new therapeutic options. The aim of this analysis is to compare the currently available new oral anticoagulants (NOACs) with VKAs and also indirectly the NOACs with each other, as it is unlikely that a head-to-head comparison will ever be available.

PATIENTS AND METHODS

In total, 27,024 patients were included in the RE-COVER, RE-COVER II, EINSTEIN DVT and PE, AMPLIFY and HOKUSAI studies with 13,511 in the VKA arm and 13,513 in the NOAC arm. Efficacy and safety endpoints were assessed by relative risks (RR) and absolute risk reductions (ARR) relative to VKA. The indirect comparison between the NOACs was performed according to ISPOR guidelines.

RESULTS

No differences between NOACs and VKA were found regarding recurrent VTE and death. Bleeding was significantly reduced by NOACs: major bleeding by rivaroxaban (RR 0.55; 0.38 - 0.81) and apixaban (RR 0.31; 0.17 - 0.55); major and clinically relevant non-major bleeding by dabigatran (RR 0.63; 0.51 - 0.77), apixaban (RR 0.44; 0.36 - 0.55) and edoxaban (RR 0.81; 0.71 - 0.93). The ARR for major bleeding was 1 % for rivaroxaban and apixaban; and for the composite bleeding endpoint 3.2 % for dabigatran, 5.4 % for apixaban, and 1.9 % for edoxaban. Regarding efficacy, no differences were found between NOACs. Apixaban reduced incidence of major bleeding more than dabigatran and edoxaban. Regarding occurrence of the composite bleeding endpoint, apixaban performed better than all other NOACs and dabigatran better than rivaroxaban and edoxaban.

CONCLUSIONS

NOACs are as efficient in the treatment of VTE as VKA but with reduced risk of bleeding complications. Indirect comparisons indicate differences in the risk of clinically relevant bleeding events. Important issues such as monitoring and reversal of anticoagulation are still unresolved, but introduction of NOACs increased the therapeutic spectrum and thereby the potential for individualized therapy.

Angio-Seal use in patients with peripheral arterial disease (ASPIRE)

PURPOSE

To investigate the incidence of complications after the use of an arterial closure device (Angio-Seal) in patients with peripheral arterial disease.

METHODS

In 105 consecutive patients after transfemoral catheterization, the puncture site was closed using a closure device (Angio-Seal). Colour-flow-duplexsonography studies were conducted 1 to 4 days before, within 3 days after and 3 month after the intervention.

RESULTS

All patients had peripheral arterial disease, 34 had calcification at the puncture site. Detection of calcification did not prevent device deployment. Complications (2 minor bleedings, 1 pseudoaneurysm) were not associated with high risk groups (these were: 69 antegrade punctures, 22 obese and 32 hypertensive patients). Three-month postinterventional diameter and blood velocity changes were <1%.

CONCLUSIONS

Patients with peripheral arterial disease in the region of the puncture site and patients at higher complication risk can safely and effectively be closed with an Angio-Seal device. At the puncture site, no lumen change can be observed 3 months postinterventional.

Overweight, obesity, and the risk of recurrent venous thromboembolism

BACKGROUND

Excess body weight is a risk factor for a first venous thromboembolism. The impact of excess body weight on risk of recurrent venous thrombosis is uncertain.

METHODS

We studied 1107 patients for an average of 46 months after a first unprovoked venous thromboembolism and withdrawal of anticoagulant therapy. Excluded were pregnant patients, those requiring long-term antithrombotic treatment, and those who had a previous or secondary thrombosis, natural coagulation inhibitor deficiency, lupus anticoagulant, or cancer. Our study end point was symptomatic recurrent venous thromboembolism.

RESULTS

A total of 168 patients had recurrent venous thromboembolism. Mean (SD) body mass index (BMI) (calculated as weight in kilograms divided by height in meters squared) was significantly higher among patients with recurrence than among those without recurrence: 28.5 (6.0) vs 26.9 (5.0) (P = .01). The relationship between excess body weight and recurrence was linear; the adjusted hazard ratio for each 1-point increase in BMI was 1.044 (95% confidence interval [CI], 1.013-1.076) (P < .001). Four years after discontinuation of anticoagulant therapy, the probability of recurrence was 9.3% (95% CI, 6.0%-12.7%) among patients of normal weight and 16.7% (95% CI, 11.0%-22.3%) and 17.5% (95% CI, 13.0%-22.0%) among overweight and obese patients, respectively. Compared with patients of normal weight, the hazard ratio of recurrence adjusted for age, sex, factor V Leiden, prothrombin G20210A mutation, high factor VIII levels, and type of initial venous thromboembolic event was 1.3 (95% CI, 0.9-1.9) (P = .20) among overweight patients and 1.6 (95% CI, 1.1-2.4) (P = .02) among obese individuals. The population attributable risk corresponding to excess body weight was 26.8% (95% CI, 5.3%-48.2%).

CONCLUSION

Excess body weight is a risk factor of recurrent venous thromboembolism.

C-reactive protein 3′ UTR +1444C>T polymorphism in patients with spontaneous venous thromboembolism

OBJECTIVE

Data on C-reactive protein (CRP) as a risk indicator of venous thromboembolism are conflicting. A recent study reported higher CRP levels in homozygous carriers of a novel CRP gene polymorphism at the 3' UTR (CRP +1444C>T). We investigated, whether homozygosity for CRP +1444C>T is associated with an increased risk of spontaneous venous thromboembolism (VTE).

METHODS AND RESULTS

CRP +1444C>T genotype and plasma levels were assessed in 128 patients with deep venous thrombosis (DVT, 70 females/58 males), 105 with pulmonary embolism (PE, 58 females/47 males) and 122 healthy individuals (60 females/62 males). CRP +1444TT was significantly associated with increased CRP plasma levels in healthy individuals. CRP +1444TT was more frequent (14%) among controls than DVT patients (9%, p=0.26) or PE patients (6%, p=0.05), respectively. No significant deviation from Hardy-Weinberg equilibrium was observed in patients (p=0.8) or controls (p=0.3), respectively. CRP +1444C>T was not significantly associated with CRP levels in patients with VTE.

CONCLUSIONS

Homozygous carriers of the CRP 3' UTR +1444C>T polymorphism do not have a significantly increased risk of VTE. Our data support the assumption that a clinically relevant association between CRP and VTE is missing.

Persistent sciatic artery: an uncommon cause of intermittent claudication

Persistent sciatic artery (PSA) is a rarely seen variation of the lower limb vessels. Anatomically the PSA is the continuation of internal iliac arteries. It follows the sciatic nerve from the sciatic foramen to the level of the knee. We report our experience with conservative therapy in a patient with complete occlusion of a PSA. A 54-year-old man with typical symptoms of intermittent claudication on the left limb was referred to our Department. After clinical examination Doppler and duplex sonography were performed. Angiography showed bilateral PSA. On the left side the PSA was occluded. The patient received 20 intravenous courses of prostaglandin E1 for 4 weeks, followed by oral anticoagulation with phenprocoumon for life (INR: 2.5-3.5). After 3 years therapy he does not show any typical symptoms of intermittent claudication or limb ischemia. This case shows that conservative therapy may be effective. However, it has to be emphasised that this approach requires frequent clinical and duplex sonography follow-up every 3 to 6 months with oral anticoagulation.

Transition from primary Raynaud's phenomenon to secondary Raynaud's phenomenon identified by diagnosis of an associated disease: results of ten years of prospective surveillance

OBJECTIVE

To assess the early signs, risk factors, and rate of transition from primary Raynaud's phenomenon (primary RP) to secondary RP.

METHODS

A clinical sample of 307 consecutive patients with RP was included in a prospective followup study. After an initial screening, 244 patients were classified as having primary RP, of whom 236 were followed up for a mean +/- SD of 11.2 +/- 3.9 years. Patients classified according to the screening as having suspected secondary RP underwent an extended screening program annually until transition to secondary RP occurred.

RESULTS

The initial prevalence of secondary RP was 11%. The annual incidence of transition to suspected secondary RP was 2%, and the annual incidence of transition to secondary RP was 1%. Overall, 46 patients were classified as having suspected secondary RP, and 23 of these later were classified as having secondary RP. Older age at onset of RP (hazard ratio 2.59, 95% confidence interval [95% CI] 1.40-4.80), shorter duration of RP at enrollment (hazard ratio 0.87, 95% CI 0.81-0.94), and abnormal findings on thoracic outlet test (hazard ratio 2.69, 95% CI 1.12-6.48) were associated with an increased risk for transition to secondary RP. Compared with patients with suspected secondary RP, those diagnosed as having secondary RP had a higher number and earlier occurrence of pathologic findings. Furthermore, antinuclear antibodies at a titer of > or = 1:320 and positive findings in specific serologic subsets were associated with a significantly increased risk for developing a connective tissue disease.

CONCLUSION

Patients diagnosed initially as having primary RP may actually comprise 1 of 3 groups: those with idiopathic RP, those with a rather benign disease course, and those with a more severe course of the disease.

Interleukin-6 and interleukin-6 promoter polymorphism (-174) G > C in patients with spontaneous venous thromboembolism

Increased levels of interleukin-6 (IL-6) have been reported in patients with a history of venous thromboembolism (VTE); however, prospective studies did not confirm an association between inflammatory markers that are highly correlated with IL-6 and the risk ofVTE. It was the aim of our study to investigate the association of IL-6 and its promoter polymorphism (-174) G > C with the risk of spontaneousVTE. IL-6 was measured in 128 patients with deep venous thrombosis (DVT,70 w/58 m),105 with pulmonary embolism (PE, 58 w/47 m) and 122 healthy controls (60 w/62 m) with a highly sensitive ELISA (Quantikine HS Human IL-6 Immunoassay, RnDSystems). The promoter polymorphism was determined by genotyping, allele specific PCR was followed by high resolution gel-electrophoresis. Median concentrations [interquartile ranges] were 2.37 [1.51-3.89] (pg/ml) in patients with DVT, 2.83 [1.83-4.87] in those with PE and 2.51 [1.71-4.78] in controls (p = 0.6, p = 0.4). Hetero- or homozygous carriers of the C allele (71% in DVT, 67% in PE and 59% among controls) did not have higher IL-6 levels than homozygous carriers of the G allele (median 2.60 vs. 2.59 pg/ml, p = 0.7). In conclusion, we found no association of IL-6 and its promoter polymorphism (-174) G > C with the risk of spontaneous VTE.

Family history for venous thromboembolism and the risk for recurrence

PURPOSE

The relevance of a family history for venous thromboembolism with regard to the likelihood for recurrence is unknown.

SUBJECTS AND METHODS

We studied 826 patients for an average of 36 months after a first unprovoked venous thromboembolism and withdrawal of oral anticoagulation. Patients with cancer, lupus anticoagulant, or deficiency of antithrombin, protein C, or protein S were excluded. The study endpoint was objective evidence of recurrent symptomatic venous thromboembolism.

RESULTS

Recurrence for venous thromboembolism was recorded in 23 of 190 patients (12.1%) with a family history (at least one affected first-degree family member) and in 79 of 636 patients (12.4%) without familial thrombosis (relative risk for recurrence 1.0; 95% confidence interval, 0.7-1.6; P=.9). At 5 years, the likelihood for recurrence was 20% among patients with a family history for venous thromboembolism and 18% among those without a family history for venous thromboembolism (P=.9). Risk determinants for venous thromboembolism including factor V Leiden, factor II G20210A, and high factor VIII were not statistically different between the 2 groups.

CONCLUSION

A family history for venous thromboembolism does not segregate patients into high- or low-risk categories and is not suitable to identify patients at increased risk for recurrent venous thromboembolism.

Tissue factor pathway inhibitor and the risk of recurrent venous thromboembolism

Tissue factor pathway inhibitor (TFPI) regulates factor X activation. Low TFPI is a risk factor for a first venous thrombosis. We evaluated whether low TFPI confers an increased risk of recurrent venous thromboembolism (VTE). TFPI-free antigen was measured in 611 patients with a first spontaneous VTE, and who were prospectively followed after withdrawal of anticoagulation. The endpoint was symptomatic recurrent VTE. The relative risk (RR) of recurrence increased from 1.0 (95% CI 0.4-2.6) in patients with TFPI levels < or = 5th percentile to 2.7 (95% CI 1.0-7.4) in patients with levels < or = 2nd percentile as compared with higher levels. At five years, the probability of recurrence was 48.6% (95th CI 19.0-78.1) among patients with TFPI < or = 2nd percentile and 16.8% (95th CI 13.8-19.8) among those with higher levels (p=0.04). Compared to patients with wild type factor V and high TFPI, the RR of recurrence was 1.1 (95% CI 0.7-1.7) in patients with factor V Leiden and high TFPI, 2.3 (95% CI 0.6-9.5) in patients with wild type factor V and low TFPI and 3.5 (95% CI 0.9-14.3) in patients with factor V Leiden and low TFPI. In a multivariate analysis,the high risk of recurrence in carriers of factor V Leiden and low TFPI slightly decreased [RR 2.8 (95% CI 0.6-9.5)]. We conclude that thrombosis patients with low levels of free TFPI are at an increased risk of recurrent VTE.

The post-thrombotic syndrome: risk factors and impact on the course of thrombotic disease

BACKGROUND

The post-thrombotic syndrome (PTS) is a frequent complication of deep vein thrombosis (DVT). Patients with recurrent ipsilateral DVT have an increased risk of PTS; other risk factors are unknown.

OBJECTIVES

To establish risk factors of PTS and its impact on venous thrombotic disease.

PATIENTS

We prospectively followed 406 patients after a first symptomatic DVT for a median of 60 months. Patients with recurrent DVT, a natural inhibitor deficiency, the lupus anticoagulant, cancer, long-term anticoagulation, an observation time < 18 months and DVT-recurrence prior PTS-assessment were excluded. Study outcomes were occurrence of PTS and recurrent symptomatic DVT.

RESULTS

PTS was assessed after 44 +/- 23 months (mean +/- SD) using a clinical classification score. PTS developed in 176 of 406 patients (43.3%). Severe PTS was rare (1.4%). Proximal DVT was the strongest risk factor of PTS [odds ratio (OR) 2.1, 95% confidence interval (CI) 1.3-3.7]. Male gender (OR 1.6, 95% CI 1.0-2.8) and elevated D-dimer levels (OR 1.9, 95% CI 1.0-3.9) were weaker risk factors. Factor V Leiden, factor II G20210A or high factor VIII did not confer an increased risk of PTS. At 4 years, the cumulative probability of recurrence was 7.4% (95% CI 3.2-11.7) among patients with PTS when compared with 1.6% (95% CI 0-3.5; P < 0.02) among patients without PTS. The risk of recurrence was 2.6-fold (95% CI 1.2-5.9) increased when PTS was present.

CONCLUSIONS

Proximal DVT, male gender, and high D-dimer levels are independently associated with the development of PTS in patients with a first DVT. Patients with PTS have an increased risk of recurrent venous thromboembolism.

Haptoglobin phenotype 2-2 as a potentially new risk factor for spontaneous venous thromboembolism

BACKGROUND AND OBJECTIVES

Haptoglobin (Hp) is a plasma protein that binds free hemoglobin and thus prevents catalysis of reactive oxygen species by the Fenton reaction. A genetic polymorphism has been described that leads to the generation of two distinct alleles, Hp1 and Hp2, which define three major haptoglobin phenotypes, denoted Hp1-1, Hp2-1 and Hp2-2. Hp2-2 has been reported to be associated with the risk of atherosclerosis and coronary heart disease. In our study we investigated the association of haptoglobin genotype and phenotype with the risk of spontaneous venous thromboembolism (VTE).

DESIGN AND METHODS

One hundred and twenty-eight patients with a history of spontaneous deep vein thrombosis (70 women, 58 men), 105 with spontaneous symptomatic pulmonary embolism (58 women, 47 men) and 122 healthy controls (60 women, 62 men) were enrolled. Haptoglobin levels were measured immunonephelometrically and phenotypes were detected by polyacrylamide gel electrophoresis and subsequent immunoblotting.

RESULTS

The Hp2-2 phenotype was significantly more prevalent in patients (42%) than in controls (30%) and significantly increased the risk for VTE in univariable (odds ratio=1.6, 95% confidence interval [1.0-2.6], p=0.04) and multivariable analyses (odds ratio=1.9 [1.0-3.4], p=0.04). Hp2-2 (n=134) was associated with significantly lower haptoglobin levels (median=89.7 mg/dL) than Hp2-1 (n=170, median = 123.5 mg/dL, p<0.001) or Hp1-1 (n=51, median=142.8 mg/dL, p<0.001).

INTERPRETATION AND CONCLUSIONS

Our study gives the first evidence that Hp2-2 represents a risk factor for spontaneous VTE, presumably through a pathophysiological mechanism similar to that in arterial disease.

Low level laser therapy in primary Raynaud's phenomenon--results of a placebo controlled, double blind intervention study

OBJECTIVE

To assess the efficacy of low level laser therapy in patients with primary Raynaud's phenomenon and predict the success of laser therapy by clinical characteristics.

METHODS

Forty-eight patients were included in a randomized placebo controlled, double blind crossover study. Laser and sham therapy each were applied 5 days a week for 3 weeks. Clinical symptoms, exposure to triggers, and frequency and intensity of attacks were recorded in diaries. Results of infrared thermography before onset and at the end of both irradiation sequences were evaluated. Primary endpoint was the average intensity of attacks; secondary endpoints were average number of attacks and thermography results. Age, sex, duration of symptoms, age at onset of symptoms, evoking conditions other than cold, maximum temperature drop after cold provocation, and rewarming time after cold provocation were tested as potential predictors.

RESULTS

Number of attacks and their intensity were significantly reduced during laser therapy compared to sham treatment. Thermographic parameters did not reach statistical significance. In a stepwise multiple regression analysis, evoking conditions other than cold (stress, wetness as additional triggers), rewarming time, and temperature decrease after cold provocation were significant predictors of therapeutic efficacy.

CONCLUSION

Low level laser therapy reduces frequency and severity of Raynaud attacks. The effect is most pronounced in patients with signs of decreased threshold for vasospasm and less effective in patients with delayed hyperemia.

Degree of atherosclerosis predicts short-term commitment for smoking cessation therapy

BACKGROUND

Only little is known about factors that influence the smokers' propensity to start smoking cessation therapy and stay within such programs.

METHODS

One hundred fifteen subjects that were current smokers and presented at the angiologic outpatient unit were enrolled in a prospective cohort study. All patients were invited to take part in a smoking cessation program. Patients' history, noninvasive vascular, cardiac, and pulmonary parameters, state of atherosclerotic disease (SMART-score), smoking history, and Fagerström index were obtained and the carbon monoxide breathing test was performed.

RESULTS

Lower age and heavy smoking were associated with less propensity to start smoking cessation therapy. The degree of atherosclerosis significantly predicted short-term commitment to smoking cessation therapy (relative risk for discontinuation: 0.82; 95% CI: 0.70-0.96). Single factors predictive for staying within the therapy were peripheral arterial occlusive disease and hyperlipidemia, while neither prior myocardial infarction nor pulmonary function was associated with compliance. Fifty-four percent of patients that completed 3 months of therapy quit smoking.

CONCLUSIONS

Counseling in smokers with preexistent or newly diagnosed atherosclerotic diseases or risk factors should include their specific vascular condition and information on positive consequences on the progress of these conditions. Counseling for initiation of smoking cessation therapy should apply different strategies as used in the maintenance phase of therapy.

The risk of recurrent venous thromboembolism in men and women

BACKGROUND

Whether a patient's sex is associated with the risk of recurrent venous thromboembolism is unknown.

METHODS

We studied 826 patients for an average of 36 months after a first episode of spontaneous venous thromboembolism and the withdrawal of oral anticoagulants. We excluded pregnant patients and patients with a deficiency of antithrombin, protein C, or protein S; the lupus anticoagulant; cancer; or a requirement for potentially long-term antithrombotic treatment. The end point was objective evidence of a recurrence of symptomatic venous thromboembolism.

RESULTS

Venous thromboembolism recurred in 74 of the 373 men, as compared with 28 of the 453 women (20 percent vs. 6 percent; relative risk of recurrence, 3.6; 95 percent confidence interval, 2.3 to 5.5; P<0.001). The risk remained unchanged after adjustment for age, the duration of anticoagulation, and the presence or absence of a first symptomatic pulmonary embolism, factor V Leiden, factor II G20210A, or an elevated level of factor VIII or IX. At five years, the likelihood of recurrence was 30.7 percent among men, as compared with 8.5 percent among women (P<0.001). The relative risk of recurrence was similar among women who had had their first thrombosis during oral-contraceptive use or hormone-replacement therapy and women in the same age group in whom the first event was idiopathic.

CONCLUSIONS

The risk of recurrent venous thromboembolism is higher among men than women.

Thrombin-activatable fibrinolysis inhibitor and the risk for recurrent venous thromboembolism

The impact of fibrinolysis for predicting the risk for recurrent venous thromboembolism (VTE) is low. We prospectively followed up 600 patients with a first VTE and evaluated the thrombin-activatable fibrinolysis inhibitor (TAFI) as a risk factor for recurrence. A high TAFI level (75th or higher percentile in thrombosis patients) was associated with a 2-fold higher risk for recurrence compared with lower levels. The probability of recurrence 2 years after anticoagulation was 14.5% (95% confidence interval [CI], 8.6-20.4) among patients with high TAFI levels and 6.8% (95% CI, 4.3-9.3) among patients with lower levels (P = .006). Our data also support the concept of a linkage between fibrinolysis and the coagulation system. Patients with high TAFI levels had significantly higher levels of factors XI, VIII, and IX, and a high risk of recurrence was seen among patients with high TAFI levels and high levels of one of these factors. The relative risk (RR) for recurrence was highest among patients with high TAFI and high factor XI (RR, 2.9; 95% CI, 1.3-6.9), high factor VIII (RR, 6.5; 95% CI, 2.9-14.8), or high factor IX (RR, 2.0; 95% CI, 1.0-3.9) levels compared with patients with low levels of TAFI and one of these factors.

Oral anticoagulation in older patients with vascular or cardiovascular diseases. Aged over 70 years: same risk? Same benefit?

AIM

The purpose of the study was to assess patients aged over 70 years and younger patients for possible differences in several aspects concerning anticoagulant therapy.

METHODS

Two-hundred and twenty-three patients with anticoagulant treatment for an average duration of 2.6 years at an angiologic outpatient clinic were subdivided into 2 groups (above 70 years n=114; below 70 years n=109). The 2 groups were compared with regard to patient-specific data, treatment-related and compliance parameters as well as complications.

RESULTS

The group of older patients included a higher number of female patients, presented with a less favorable risk profile and revealed tendency or significance in showing better compliance data. No differences were found for the incidence of bleeding complications, while recurrences were more frequent in patients below the age of 70 years. Treatment-related parameters reflecting quality and stability of anticoagulant therapy (standard deviation of international ratio (INR), frequency of laboratory controls) represent predictors of bleeding risk being of more critical importance than the age of the patient. Recurrent events also showed correlation with same relevant parameters. Younger patients undergoing the same intensity of treatment for similarly distributed indications show a higher rate of recurrences.

CONCLUSION

The lower recurrence rate in older patients is consistent with the observation that anticoagulant therapy is more profitable in elderly with atrial fibrillation. Since older patients being treated with the same therapy intensity for comparable periods of time showed no higher bleeding risk than that seen for younger patients, we believe that there is no need for specific guidelines for older patients provided treatment is carefully monitored and controlled.

D-dimer levels and risk of recurrent venous thromboembolism

CONTEXT

Widespread screening of patients with venous thromboembolism (VTE) for thrombophilic risk factors has become common clinical practice. Because of the increasing number of risk factors, assessing the risk of recurrence in an individual patient is intricate; therefore, a laboratory method that measures multifactorial thrombophilia is required.

OBJECTIVE

To prospectively study the relationship between the risk of recurrent VTE and D-dimer, a global marker of coagulation activation and fibrinolysis.

DESIGN, SETTING, AND PARTICIPANTS

Prospective cohort study of 610 patients older than 18 years who were treated with oral anticoagulants for at least 3 months with a first spontaneous VTE, in whom D-dimer levels were measured shortly after discontinuation of oral anticoagulation. The study was conducted at the Department of Internal Medicine I, University Hospital, Vienna, Austria. Patients entered the study at time of discontinuation of oral anticoagulants and were observed at 3-month intervals during the first year and every 6 months thereafter from July 1992 to October 2002.

MAIN OUTCOME MEASURE

Objectively documented symptomatic recurrent VTE.

RESULTS

A total of 79 (13%) of 610 patients had recurrent VTE with a mean observation time of 38 months. Patients with recurrence had significantly higher D-dimer levels compared with those without recurrence (553 ng/mL vs 427 ng/mL, P =.01). Compared with patients with D-dimer levels of 750 ng/mL or higher, the relative risk (RR) of recurrence was 0.6 (95% confidence interval [CI], 0.3-1.4), 0.6 (95% CI, 0.3-1.2), and 0.3 (95% CI, 0.1-0.6) in patients with D-dimer levels of 500 to 749 ng/mL, 250 to 499 ng/mL, and less than 250 ng/mL, respectively. The cumulative probability of recurrent VTE at 2 years was 3.7% (95% CI, 0.9%-6.5%) among patients with D-dimer levels of less than 250 ng/mL compared with 11.5% (95% CI, 8.0%-15.0%) among patients with higher levels (P =.001). Patients with D-dimer levels of less than 250 ng/mL had a 60% lower RR of recurrence compared with patients with higher levels (RR, 0.4; 95% CI, 0.2-0.8).

CONCLUSION

Patients with a first spontaneous VTE and a D-dimer level of less than 250 ng/mL after withdrawal of oral anticoagulation have a low risk of VTE recurrence.

Superficial thrombophlebitis and risk for recurrent venous thromboembolism

OBJECTIVE

Superficial thrombophlebitis (ST) is a frequent and potentially serious disease if complicated with venous thromboembolism (VTE). Data on risk factors and incidence rates for ST are scarce. It is also unknown whether ST is a risk factor for recurrence of VTE.

METHODS

After discontinuation of secondary thromboprophylaxis for a first spontaneous VTE, we prospectively observed 615 patients on average for 30 +/- 26 months. Patients with natural coagulation inhibitor deficiency, lupus anticoagulant, or cancer, who were pregnant, or were receiving long-term antithrombotic therapy were excluded. The study outcomes were occurrence of symptomatic ST or objectively documented recurrent symptomatic VTE.

RESULTS

ST developed in 45 patients (7.3%) with a first VTE. High factor VIII concentration emerged as an independent risk factor for ST (relative risk [RR], 2.0; 95% confidence interval [CI], 1.0-5.2), compared with lower levels after adjustment for age and sex; factor V Leiden and prothrombin G20210A concentration; hyperhomocysteinemia; high body mass index; and duration of oral anticoagulation therapy. VTE recurred in 12 (27%) of 45 patients with ST and in 67 (12%) of 570 patients without ST. In patients with VTE, subsequent ST emerged as an independent risk factor for recurrent VTE. Patients with ST had twofold higher RR (2.1; 95% CI, 1.0-4.2) for recurrence than did patients without ST after adjustment for putative confounding variables.

CONCLUSION

Patients with a first spontaneous VTE and subsequent ST are at increased risk for recurrent VTE. High factor VIII concentration is an independent risk factor for ST.

The risk of recurrent venous thromboembolism among patients with high factor IX levels

High factor IX (FIX) is a risk factor of deep vein thrombosis. The impact of high FIX on the risk of recurrent venous thrombosis is unknown. We prospectively followed 546 patients after anticoagulation for a first spontaneous venous thromboembolism. Patients with a natural coagulation inhibitor deficiency, lupus anticoagulant or cancer were excluded. At 3 years, the likelihood of recurrence was 23% among patients with high FIX (exceeding the 75th percentile) compared with 11% among patients with lower levels. Among patients with high FIX, the relative risk of recurrence was 2.2 (95% CI: 1.3-3.6) before and was 1.6 (95% CI: 1.0-2.8) after adjustment for age, gender, duration of anticoagulation, FV Leiden, FII G20210A, high FVIII and hyperhomocysteinemia. Compared with patients with low factor IX (< 138 IU dL(-1)) and low FVIII ( Collapse

Key Words Collapse

MESH Headings

• Adult
• Aged
• Anticoagulants/therapeutic use
• Factor IX/analysis
• Factor VIII/analysis
• Female
• Humans
• Incidence
• Male
• Middle Aged
• Prospective Studies
• Recurrence
• Risk Factors
• Thromboembolism/blood
• Venous Thrombosis/blood

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Grants Collapse

The risk of recurrent venous thromboembolism in heterozygous carriers of factor V Leiden and a first spontaneous venous thromboembolism

BACKGROUND

Factor V (FV) Leiden is a risk factor for venous thrombosis (VT). Data on its influence on the risk of recurrent venous thromboembolism (VTE) are controversial owing to different study designs and patient cohorts.

METHODS

We reevaluated the risk of recurrence among heterozygous carriers and noncarriers of FV Leiden with a first spontaneous proximal VT of the leg and/or pulmonary embolism. Patients with secondary VTE, homozygous FV Leiden, natural inhibitor deficiencies, lupus anticoagulant, cancer, or long-term anticoagulation were excluded. The study end point was objectively documented, symptomatic, recurrent VTE.

RESULTS

After discontinuation of oral anticoagulant therapy for a first VTE, we prospectively observed 287 patients, 83 (29%) of whom were heterozygous for FV Leiden. Recurrent VTE was seen in 17 (20%) of 83 patients with and 44 (21.6%) of 204 without FV Leiden. The probability of recurrence among heterozygotes was 12% (95% confidence interval [CI], 8%-16%), 27% (95% CI, 21%-33%), and 27% (95% CI, 21%-33%) after 2, 4, and 6 years, respectively, and was not higher than that among patients without the mutation (16%, 23%, and 34%, respectively). The relative risk of recurrence in heterozygotes was 0.9 (95% CI, 0.5-1.6; P =.60) after adjustment for confounding variables. The risk of recurrence among patients with and without FV Leiden was not different when sex distribution or duration of anticoagulation therapy was taken into account.

CONCLUSIONS

The risk of recurrence is similar among carriers and noncarriers of FV Leiden. Heterozygous patients should receive secondary thromboprophylaxis for a similar length of time as patients without FV Leiden.

Duplex sonographic predictors of restenosis, vascular and neurological events after carotid endarterectomy

BACKGROUND

Although excellent short- and long-term results have been achieved with surgery in extracranial internal carotid artery stenosis, recurrent stenosis continues to play an important role in post-endarterectomy. Therefore, a close follow-up of patients is warranted. The value of postoperative duplex sonographic evaluations in postoperative follow-up is highly disputed. The study evaluates duplex sonographic parameters as predictors of carotid restenosis, general vascular events and ipsilateral neurological symptoms, in order to assess the role of duplex sonography in follow-up after carotid endarterectomy.

METHODS

A retrospective cohort study with a follow-up period ranging from 7 months to 7.5 years was performed in 150 patients who underwent carotid endarterectomy. Pre- and postoperative duplex sonographic and clinical data were analyzed by life-table analysis and multivariate Cox regression with respect to carotid restenosis, vascular and ipsilateral neurological events.

MAIN FINDINGS

Duplex sonographic predictors of carotid restenosis include the postoperative degree of stenosis (residual stenosis > or = 30% or more: relative risk (RR) = 1.56; 1.05-2.32), pre- to postoperative reduction of stenosis (higher than 50%: RR = 0.61; 0.45-0.83), and residual plaques in the operated carotid artery (RR = 1.96; 1.31-2.93). Some of these morphological parameters such as reduction of stenosis are also predictive of vascular events (RR = 1.25; 1.01-1.56) and ipsilateral neurological events (RR = 1.52; 1.05-2.19). In 12 cases restenosis was discovered by duplex sonography and in 3 cases by evaluation of clinical symptoms. In 5 cases restenosis was treated by repeat surgery. Contralaterally, progressive or newly developed carotid stenoses were observed in 17 cases, and only 5 were discovered on the basis of clinical symptoms. Fourteen contralateral stenoses required surgery. Overall, 12 patients underwent treatment for stroke prevention on the basis of duplex follow-up findings (8% of the study population).

CONCLUSIONS

Postoperative duplex sonography allows for the identification of patients at risk for carotid restenosis as well as those at risk for other vascular events. As expected, regular examinations permit early detection of restenosis requiring surgical treatment. However, a large number of contralateral stenoses requiring surgical treatment were detected by routine duplex sonographic examinations. The timing of follow-up intervals may be oriented towards the perioperative outcome of duplex sonography.

Double-blind, randomised, placebo controlled low level laser therapy study in patients with primary Raynaud's phenomenon

BACKGROUND

No causal treatment of primary Raynaud's phenomenon is available due to its unclear aetiology. Low level laser therapy (LLLT) is applied in a multitude of medical conditions often without sufficient evidence of efficacy and established mechanisms. To asses the effect of this therapy in patients with primary Raynaud's phenomenon a randomised, double blind, placebo controlled cross over study was designed.

PATIENTS AND METHODS

Absolute and relative frequency and intensity of vasospastic attacks during three weeks of either LLLT or placebo therapy and results of infrared thermography before onset and at the end of both therapy sequences were evaluated in 15 patients with primary Raynaud's phenomenon.

RESULTS

Frequency of Raynaud's attacks was not significantly affected by low level laser therapy. Compared to placebo a significantly lower intensity of attacks during laser irradiation was observed, but no transfer effect occurred. Additionally the mean temperature gradient after cold exposure was reduced after laser irradiation, while the number of fingers showing prolonged rewarming was unaffected.

CONCLUSION

Though further studies are necessary to confirm these results we could demonstrate for the first time in a double blind placebo controlled clinical trial that low laser therapy is a potential candidate for an effective therapy of Raynaud's phenomenon, although effects seem to be of short duration.

[Aneurysm of the popliteal vein]

Venous aneurysms are a rare pathology. The possible complications are rupture, thrombosis and subsequently pulmonary embolism. The case of a 54-year-old male is reported, who was admitted on the suspicion of pulmonary embolism to our department. This suspicion was confirmed by scintigraphy and computed tomography. Further examination by colour coded duplex sonography showed an aneurysm of the popliteal vein in clinically asymptomatic legs, as a possible cause of the pulmonary embolism. The finding was confirmed phlebographically. After successful surgical treatment of the aneurysm the patient got an anticoagulation therapy for 6 months. In the case of thromboembolism the entire venous system can be affected. Therefore an examination of the peripheral veins should be carried out whenever there is an occurrence of pulmonary embolism.

Reisethrombose 2001

Anlässlich einer Tagung in Wien im Juni 2001 hat eine Gruppe von Experten aus Deutschland, der Schweiz und aus Österreich ein Dokument ausgearbeitet, in welchem eine Definition der Reisethrombose gegeben und Vorbeugemaßnahmen vorgeschlagen wurden, die an drei Risikogruppen angepasst sind.

High plasma levels of factor VIII and the risk of recurrent venous thromboembolism

BACKGROUND

A high plasma level of factor VIII is a risk factor for venous thromboembolism. We evaluated the risk of a recurrence of thrombosis after an initial episode of spontaneous venous thromboembolism among patients with high plasma levels of factor VIII.

METHODS

We studied 360 patients for an average follow-up period of 30 months after a first episode of venous thromboembolism and discontinuation of oral anticoagulants. Patients who had recurrent or secondary venous thromboembolism, a congenital deficiency of an anticoagulant, the lupus anticoagulant, hyperhomocysteinemia, cancer, or a requirement for long-term treatment with antithrombotic drugs or who were pregnant were excluded. The end point was objectively documented, symptomatic recurrent venous thromboembolism.

RESULTS

Recurrent venous thromboembolism developed in 38 of the 360 patients (10.6 percent). Patients with recurrence had higher mean (+/-SD) plasma levels of factor VIII than those without recurrence (182+/-66 vs. 157+/-54 IU per deciliter, P=0.009). The relative risk of recurrent venous thrombosis was 1.08 (95 percent confidence interval, 1.04 to 1.12; P<0.001) for each increase of 10 IU per deciliter in the plasma level of factor VIII. Among patients with a factor VIII level above the 90th percentile of the values in the study population, the likelihood of recurrence at two years was 37 percent, as compared with a 5 percent likelihood among patients with lower levels (P<0.001). Among patients with plasma factor VIII levels above the 90th percentile, as compared with those with lower levels, the overall relative risk of recurrence was 6.7 (95 percent confidence interval, 3.0 to 14.8) after adjustment for age, sex, the presence or absence of factor V Leiden or the G20210A prothrombin mutation, and the duration of oral anticoagulation.

CONCLUSIONS

Patients with a high plasma level of factor VIII have an increased risk of recurrent venous thromboembolism.

The risk of early recurrent venous thromboembolism after oral anticoagulant therapy in patients with the G20210A transition in the prothrombin gene

A G20210A transition in the prothrombin gene is a common risk factor of venous thrombosis. The risk of recurrent venous thromboembolism in carriers of the 20210A allele is unknown and guidelines for secondary thromboprophylaxis in these patients are not available. In a prospective multicenter trial, 492 patients with a history of objectively documented venous thromboembolism were followed for a mean observation time of 24+/-16 months after discontinuation of oral anticoagulants. Forty-two patients (8.5%) were carriers of the 20210A allele. Three of the 42 patients with the G20210A mutation (7%) and 54 of 450 patients without the mutation (12%) experienced recurrent venous thrombosis. At 24 months, the probability of recurrence was 8% (95% CI 0-16.7) in patients with the mutation and was 12.2% (95% CI 8.8-15.6) in patients without the mutation. In conclusion, the risk of early recurrent venous thromboembolism is not higher in patients with the G20210A mutation than in those without the mutation. Therefore, long-term secondary thromboprophylaxis with oral anticoagulants in heterozygous carriers of the 20210A allele is not justified.

Hyperhomocysteinemia is a risk factor of recurrent venous thromboembolism

Hyperhomocysteinemia is a risk factor of venous thromboembolism. The risk of recurrence in patients with hyperhomocysteinemia is unknown, and the optimal therapy for these patients after acute venous thromboembolism is uncertain. In a multicenter study, 264 patients with an objectively documented single episode of idiopathic venous thromboembolism were prospectively followed after discontinuation of oral anticoagulants. Patients were classified as hyperhomocysteinemic if their homocysteine levels exceeded the 95th percentile of the controls. The outcome events studied were objectively confirmed deep-vein thrombosis and/or pulmonary embolism. Homocysteine levels were elevated in 66 patients (25%) and normal in 198 patients (75%). Recurrent venous thromboembolism occurred in 12 of 66 patients with hyperhomocysteinemia (18.2%) and in 16 of 198 patients without hyperhomocysteinemia (8.1%). The cumulative probability of recurrence 24 months after discontinuation of oral anticoagulants was 19.2 percent (95 percent confidence interval 8.7-27) in patients with hyperhomocysteinemia and was 6.3 percent (95 percent confidence interval 2.4-10.1; p = 0.001) in those without hyperhomocysteinemia. The relative risk of recurrent thrombosis was higher in patients with hyperhomocysteinemia [RR 2.7 (1.3-5.8), p = 0.009]. Patients with hyperhomocysteinemia are at high risk of recurrent venous thromboembolism. The high prevalence of hyperhomocysteinemia in thrombosis patients together with the increased risk of recurrence warrants extended patient screening. The impact on the risk of recurrence of prolonged anticoagulation, supplementation of folate and vitamin B12, or both have to be investigated.

Clinical studies and thrombin generation in patients homozygous or heterozygous for the G20210A mutation in the prothrombin gene

A genetic variation in the prothrombin gene, the G-->A transition at nucleotide 20210, is a risk factor for venous thrombosis in heterozygotes and is associated with increased prothrombin activity. The homozygous phenotype and the extent of thrombin generation in heterozygous and homozygous subjects are unknown. We investigated a family that included 2 homozygous and 5 heterozygous carriers of the 20210 A allele. The homozygous propositus and his presumably heterozygous father suffered from deep-vein thrombosis. His presumably heterozygous mother and his homozygous sister had recurrent phlebitis at a young age. The remaining 5 affected family members are still asymptomatic. We studied thrombin generation in the family and in 22 unrelated carriers of the 20210 A allele by measuring (1) prothrombin fragment F1+2 (F1+2) as an index of ongoing thrombin generation and (2) the endogenous thrombin potential (ETP) as an index of the possible thrombin-forming capacity. Their F1+2 levels were not different from those of age-matched controls, and thus, ongoing hemostatic system activation was not detectable. A significantly increased ETP was found in the heterozygous carriers of the 20210A allele compared with the controls (527.8+/-114.9 versus 387+/-50.1 nmol/L x min, P<0.0001). In the 2 homozygotes, the ETP was almost twice (639 and 751 nmol/L x min, respectively) as high as in the controls. We conclude that homozygosity for the G20210A mutation in the prothrombin gene is associated with a severe, albeit more benign, thrombotic diathesis compared with homozygosity for deficiencies of antithrombin, protein C, or protein S. In carriers of the 20210 A allele, the pathomechanisms leading to thrombosis should be sought in the higher amounts of thrombin that may be formed once thrombin generation is triggered, rather than in ongoing thrombin generation in vivo.

Levels of prothrombin fragment F1+2 in patients with hyperhomocysteinemia and a history of venous thromboembolism

Increased thrombin generation occurs in many individuals with inherited defects in the antithrombin or protein C anticoagulant pathways and is also seen in patients with thrombosis without a defined clotting abnormality. Hyperhomocysteinemia (H-HC) is an important risk factor of venous thromboembolism (VTE). We prospectively followed 48 patients with H-HC (median age 62 years, range 26-83; 18 males) and 183 patients (median age 50 years, range 18-85; 83 males) without H-HC for a period of up to one year. Prothrombin fragment F1+2 (F1+2) was determined in the patient's plasma as a measure of thrombin generation during and at several time points after discontinuation of secondary thromboprophylaxis with oral anticoagulants. While on anticoagulants, patients with H-HC had significantly higher F1+2 levels than patients without H-HC (mean 0.52 +/- 0.49 nmol/l, median 0.4, range 0.2-2.8, versus 0.36 +/- 0.2 nmol/l, median 0.3, range 0.1-2.1; p = 0.02). Three weeks and 3, 6, 9 and 12 months after discontinuation of oral anticoagulants, up to 20% of the patients with H-HC and 5 to 6% without H-HC had higher F1+2 levels than a corresponding age- and sex-matched control group. 16% of the patients with H-HC and 4% of the patients without H-HC had either F1+2 levels above the upper limit of normal controls at least at 2 occasions or (an) elevated F1+2 level(s) followed by recurrent VTE. No statistical significant difference in the F1+2 levels was seen between patients with and without H-HC. We conclude that a permanent hemostatic system activation is detectable in a proportion of patients with H-HC after discontinuation of oral anticoagulant therapy following VTE. Furthermore, secondary thromboprophylaxis with conventional doses of oral anticoagulants may not be sufficient to suppress hemostatic system activation in patients with H-HC.

Prothrombin fragment F1+2 is not predictive for recurrent venous thromboembolism

It would be important to estimate in advance the risk of recurrent thrombosis. Deficiencies of antithrombin, protein C or protein S, or resistance to activated protein C are associated with a biochemically detectable prethrombotic state. It is thus far unknown whether in patients with a history of thromboembolism but without a defined clotting abnormality a heightened coagulation activation is detectable. We investigated the value of prothrombin fragment F1+2 (F1+2) as a predictor of recurrent venous thromboembolism. Furthermore, we compared the F1+2 levels of thrombosis patients without a defined clotting defect to those of Factor V Leiden patients with a history of venous thrombosis and to those of healthy controls. 180 patients without a defined clotting abnormality and 73 patients with Factor V Leiden were prospectively followed after discontinuation of oral anticoagulants for venous thrombosis and F1+2 was measured at regular intervals. Recurrent venous thromboembolism occurred in 23 (9%) of the 253 patients. Before or at several time points after oral anticoagulants, no significant difference in F1+2 levels was found in patients with and without recurrent thrombosis. F1+2 levels at 3 weeks and prior to recurrence were not significantly different in both patient groups. Over a one-year observation period, F1+2 levels of both patients with and without Factor V Leiden were higher than those of the controls. No difference in F1+2 was seen between patients with and without Factor V Leiden. We conclude that monitoring of F1+2 is not suitable for identification of individuals at risk of recurrent venous thrombosis. Permanent hemostatic system activation is detectable both in patients with a defined abnormality of the clotting system and in patients in whom a particular defect has not (yet) been identified.

The risk of recurrent venous thromboembolism in patients with and without factor V Leiden

Thromboprophylaxis with oral anticoagulants up to six months is established in patients after a first venous thromboembolic event (VTE). The risk of recurrent VTE is still considerable thereafter, and it is uncertain whether some patients might benefit from extended anti-coagulation. We performed a prospective, multicenter trial (4 thrombosis centers) and evaluated in 380 patients with a first or recurrent VTE (patients with a deficiency of antithrombin, protein C, protein S or plasminogen; cancer; or an antiphospholipid antibody syndrome were excluded) the risk of recurrence after discontinuation of secondary thromboprophylaxis with oral anticoagulants. It was the aim of the study to evaluate whether patients, with factor V Leiden are at an increased risk of recurrent VTE. 112 (29.5%) patients were carriers of factor V Leiden (26.9% heterozygous, 2.6% homozygous). After a median observation time of 19.3 months the overall recurrence rate of VTE was 9.9%. Recurrent deep vein thrombosis and/or pulmonary embolism occurred in 26 of 268 patients without factor V Leiden (9.7%) and in 10 of 112 patients with factor V Leiden (8.9%). The probability of recurrent VTE two years after discontinuation of oral anticoagulants was 12.4% (95% CI 7.8-17) in patients without factor V Leiden and was 10.6% (95% CI 3.8-17.4) in carriers of the mutation. This difference was statistically not significant. Patients with factor V Leiden are not at a higher risk of recurrent VTE within two years after discontinuation of oral anticoagulants than patients without factor V Leiden. Balancing the risk of recurrent VTE and bleeding from oral anticoagulants, patients with factor V Leiden are not likely to benefit from oral anticoagulant therapy extended beyond six months.

Five-year follow-up of patients after thromboendarterectomy of the internal carotid artery: Relevance of baroreceptor sensitivity

BACKGROUND AND PURPOSE

In patients after myocardial infarction, baroreceptor sensitivity has been identified as a factor of prognostic relevance. This study was designed to assess the effects of an increased baroreceptor sensitivity in patients after surgery in the area of the internal carotid artery with respect to blood pressure variability, therapeutic interventions, and vascular events during a 5-year follow-up.

METHODS

Receptor sensitivity before and immediately after carotid surgery was measured in 84 patients. Blood pressure variability, carotid artery status, and echocardiographic findings were assessed before and after surgery and at the end of follow-up. Vascular events as well as changes in blood pressure therapy during the follow-up period were evaluated.

RESULTS

Significant negative correlations between an increase of baroreceptor sensitivity after surgery and the range of systolic (r=-.47; P<.001) and diastolic (r=-.33; P<.01) blood pressure were found for the immediate postoperative period. For the range of systolic blood pressure, this relation persisted (4.3 to 7 years after surgery) at the end of the observation period (r=-.38; P<.001). An inverse relation to the increase in baroreceptor function was also found for the average annual number of therapeutic interventions during follow-up (r=-.38; P<.001). Furthermore, the subgroup of patients without a postoperative increase of receptor sensitivity was characterized by a significantly higher risk of major vascular events (log-rank test, P<.018).

CONCLUSIONS

Because an improvement of receptor sensitivity after carotid surgery is related to a long-lasting reduction of blood pressure levels and variability, baroreceptor function may be considered an indirect indicator for the later postoperative course.

Initial prevalence and incidence of secondary Raynaud's phenomenon in patients with Raynaud's symptomatology

OBJECTIVE

To establish the initial prevalence and incidence of secondary Raynaud's phenomenon (RP) in an outpatient population presenting with RP and assessment of the discriminating and predictive value of the variables of a diagnostic program.

METHODS

112 patients (average followup time 46 mo) were investigated prospectively. A screening program including anamnestic data, clinical examinations, noninvasive angiologic measurements, radiographic examinations, and laboratory chemistry was applied initially and repeated every 6 months. Patients with suspected secondary RP according to the screening underwent an extended diagnostic program.

RESULTS

Based on the initial screening, 73 patients were classified as primary RP and 39 patients as suspected secondary RP. After examinations of the extended diagnostic program, 16 patients were diagnosed as secondary RP (initial prevalence 14.3%). During followup another 5 patients were diagnosed as secondary RP (annual incidence 1.4%). Using stepwise logistic regression, 7 screening variables were included in a model, leading to 96% correct classifications (sensitivity 86%, specificity 100%). Most of these variables were also suitable to predict the transition to secondary RP. An alternative classification based on a total symptoms score led to 94% correct classifications (sensitivity 86%, specificity 96%).

CONCLUSION

The diagnostic program proved adequate and effective. Patients with RP and related arterial circulatory disorder showed a different clinical course than patients with an immunopathogenesis. A combination of several variables seems to be superior, with respect to the prediction and differentiation of secondary RP, to an approach based on single variables.