Venous thromboembolism from air travel: the LONFLIT study.

The LONFLIT study was planned to evaluate the incidence of deep venous thrombosis (DVT) occurring as a consequence of long flights. In the Lonflit study 355 subjects at low-risk for DVT and 389 at high-risk were studied. Low-risk subjects had no cardiovascular disease and used no drugs. All flights were in economy class. The average flight duration was 12.4 hours (range, 10-15 hr). The mean age of the studied subjects was 46 years (range 20-80 yr, SD 11; 56% males). DVT diagnosis was made by ultrasound scans after the flights (within 24 hours). In low-risk subjects no events were recorded while in high-risk subjects 11 had DVT (2.8%) with 13 thromboses in 11 subjects and 6 superficial thromboses (total of 19 thrombotic events in 389 patients [4.9%]). In the Lonflit2 study the authors studied 833 subjects (randomized into 422 control subjects and 411 using below-knee stockings). Mean age was 44.8 years (range, 20-80 yr, SD 12; 57% males). The average flight duration was 12.4 hours. Scans were made before and after the flights. In the control group there were 4.5% of subjects with DVT while only 0.24% of subjects had DVT in the stockings group. The difference was significant. The incidence of DVT observed when subjects were wearing stockings was 18.75 times lower than in controls. Long-haul flights are associated to DVT in some 4-5% of high-risk subjects. Below-knee stockings are beneficial in reducing the incidence of DVT.     

Prevention of edema,flight microangiopathy and venous thrombosis in long flights with elastic stockings. A randomized trial: The LONFLIT 4 Concorde Edema-SSL Study

The LONFLIT1/2 studies have established that in high-risk subjects after long (> 10 hours) flights the incidence of deep venous thrombosis (DVT) is between 4% and 6%. The LONFLIT4 study has been planned to evaluate the control of edema and DVT in low-medium-risk subjects. The aim of this study was to evaluate edema and its control with specific flight stockings, in long-haul flights. In the first part of the study 400 subjects at low-medium risk for DVT were contacted; 28 were excluded for several nonmedical problems; 372 were randomized into 2 groups to evaluate prophylaxis with stockings in 7-8-hour flights; the control group had no prophylaxis. Below-knee, Scholl, Flight Socks, producing 14-17 mm Hg of pressure at the ankle, were used in the treatment group. The occurrence of DVT was evaluated with high-resolution ultrasound scanning (femoral, popliteal, and tibial veins). Edema was assessed with a composite score based on parametric and nonparametric measurements. Part II: In this part of the study 285 subjects at low-medium risk for DVT were included and randomized into 2 groups to evaluate edema prophylaxis in 11-12-hour flights; the controls had no prophylaxis while the prevention group had below-knee, Scholl, Flight Socks (comparable to part I). RESULTS: Part 1: DVT evaluation. Of the 184 included subjects in the stockings group and 188 in the control group, 358 (96.2%) completed the study. Dropouts were due to compliance or connection problems. Age/sex distributions were comparable in the groups. Stockings Group: of 179 subjects (mean age 49; SD 7; M:F = 101:78), none had DVT or superficial thromboses. Control Group: of 179 subjects (mean age 48.4; SD 7.3; M:F = 98:81), 4 (2.2%) had a DVT. There were also 2 superficial thromboses. In total, 3.35% (6) subjects had a thrombotic event. The difference (p<0.002) is significant. Intention-to-treat analysis detects 15 failures in the control group (9 lost + 6 thromboses) out of 188 subjects (7.9%) versus 5 subjects (2.7%) in the stockings group (p <0.05). All thrombotic events were observed in passengers sitting in nonaisle seats. The tolerability of the stockings was very good and there were no complaints or side effects. Thrombotic events were asymptomatic. No difference was observed in the distribution of events between men and women. The 3 women who had a thrombotic event were taking low-dose, oral contraceptives. Edema evaluation: The level of edema at inclusion was comparable in the 2 groups. After the flight there was a score of 6.7 (3.1) in controls; in the stockings group the score was 2.9 times lower (p<0.05). The control of edema with stockings was clear considering both parametric (circumference, volume) and nonparametric (analogue scale lines) data. Part II: DVT evaluation. Of the 285 included subjects, 271 (95%) completed the study. Dropouts were due to low compliance or connection problems. Age/sex distributions were comparable in the groups. Stockings Group: of 142 subjects (mean age 48; SD 8; M:F = 89:53), none had DVT or superficial thromboses. Control Group: of 143 subjects (mean age 47; SD 8; M:F = 87:56), 3 had a popliteal DVT and 3 a superficial thrombosis. In total, 4.2% (6) subjects had a thrombotic event. The difference (p<0.02) between groups is significant. Intention-to-treat analysis detects 14 failures in the control group (8 lost + 6 thromboses = 9.7%) versus 6 (all lost = 4.2% in the stockings group) (p<0.05). Four of 6 events (3 DVT + 1 SVT) were observed in non-aisle seats. The tolerability of the stockings was very good. No difference was observed in the distribution of events between men and women. Edema evaluation: The level of edema at inclusion was comparable in the 2 groups. After the flight there was a score of 8.08 (2.9) in controls while in the stockings group the score was 2.56 (1.5) (p < 0.005). In conclusion. Scholl Flight Socks are very effective in controlling edema. Also this type of compression is effective in significantly reducing the incidence of DVT and thrombotic events in low-medium-risk subjects, in long-haul flights. CONCLUSIONS: Considering these observations, Flight Socks are effective in controlling edema and in reducing the incidence of DVT in low-medium-risk subjects, in long-haul flights (7-11 hours).     

The LONFLIT4--Concorde Deep Venous Thrombosis and Edema Study: prevention with travel stockings

BACKGROUND: The LONFLIT1+2 studies have established that in high risk subjects after long flights (> 10 hours) the incidence of deep venous thrombosis (DVT) is between 4% and 6%. The LONFLIT4 study was designed to evaluate the control of edema and DVT in low-medium risk subjects. The aim of this study was to evaluate edema and its control with specific stockings (ankle pressure between 20 and 30 mm Hg) in long-haul flights. The first part of the study included flights lasting 7-8 hours and the second part included flights lasting 11-12 hours. Ultrasound scans were used to assess thrombosis before and after the flights and a composite edema score was used to evaluate edema and swelling. A group of patients with microangiopathy associated to edema (diabetes, venous hypertension, anti-hypertensive treatment) were also included to evaluate the preventive effects of stockings during flight. Part I: DVT evaluation: Of the 74 subjects in the stocking group and 76 in the control group (150), 144 completed the study. Dropouts were due to low compliance or traveling and connection problems. Age and gender distribution were comparable in the 3 groups as was risk factor distribution. In this part of the study there were no DVTs. Edema Evaluation: The level of edema at inclusion was comparable in the two groups of subjects. After the flight there was an average score of 6.9 (1) in the control group. In the stocking group, the score was on average 2.3 (1), three times lower than in the control group (p < 0.05). Part II: DVT evaluation: Of the 66 included subjects in the stocking group and 68 in the control group (134), 132 completed the study. Dropouts were due to low compliance or connection problems. Age and gender distribution were comparable in the two groups. In the stocking group no DVT was observed. In the control group, 2 subjects had a popliteal DVT and 2 subjects had superficial venous thrombosis (SVT); in total 4 subjects (6%) in the control group had a thrombotic event; the incidence of DVT was 3%. The difference (p < 0.02) is significant. EDEMA EVALUATION: The composite edema score at inclusion was comparable in the two groups. After the flight there was a score of 7.94 (2) in the control group, while in the treatment group the score was 3.3 (1.2). MICROANGIOPATHY STUDY: In all these subjects, the level of edema was very high in the control group and significantly lower in the compression stocking group. Stockings are effective in controlling edema during flights even in subjects with microangiopathy and edema. Compression was well tolerated in normal subjects and in patients. CONCLUSION: The Kendall Travel Socks (Tyco Healthcare, Mansfield, MA, USA) which provide 20-30 mm Hg pressure at the ankle, are effective in controlling edema and reducing the incidence of DVT in both low-medium-risk subjects and in patients with microangiopathy and edema in long-haul flights (7-11 hours).     

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.     

The LONFLIT4-Concorde--Sigvaris Traveno Stockings in Long Flights (EcoTraS) Study: a randomized trial

The LONFLIT1/2 studies have established that in high-risk subjects after long ( > 10 hours) flights the incidence of deep venous thrombosis (DVT) may be between 4% and 6%. The LONFLIT4 study was aimed at evaluating the control of edema and DVT prevention in low-medium-risk subjects. In this study prophylaxis of edema with specific travel stockings was evaluated in 2 separate studies involving flights lasting 7 hours and 10-12 hours. Part I. Subjects at low-medium risk for DVT were contacted; 55 subjects were excluded for several nonmedical, travel-related problems or inconvenient evaluation time; the remaining 211 were randomized into 2 groups to evaluate prophylaxis with elastic stockings in 7-8-hour, long-haul flights. The control group had no prophylaxis; the treatment group used below-knee, Sigvaris Traveno elastic stockings (Ganzoni, Switzerland, producing 12-18 mm Hg of pressure at the ankle). Color duplex scanning was used to evaluate the possible presence of DVT; edema/swelling were evaluated with a composite score including the presence of edema (with an edema tester), variations in ankle circumference and leg volumetry, subjective swelling, and discomfort (scale ranging from 0 to 10). Results: Of the 103 included subjects in the stockings group and 108 in the control group (total 211), 195 subjects completed the study. Dropouts (16) were due to low compliance or traveling and connection problems. Age, sex distribution, and risk factors distributions were comparable in the 2 groups. Stockings Group: Of 97 subjects none had DVT or superficial thromboses. Control Group: Of 98 subjects none had thrombosis. The level of edema at inclusion was comparable in the 2 groups of subjects. After flights there was an average score of 6.4 (1.3) in the control group, while in the stockings group the score was on average 2.4 (SD 1), 2.6 times lower than in the control group (p < 0.05). In the control group 83% of the subjects had an evident increase in ankle circumference and volume that was visible at inspection and associated with discomfort. The control of edema with stockings was clear, considering both parametric data (circumference and volume) and nonparametric (analogue scale lines) measurements. Part II. In this part of the study 200 subjects at low-medium risk for DVT were contacted; 35 subjects were excluded for several nonmedical, travel-related problems or inconvenient evaluation time; the remaining 165 were randomized into 2 groups to evaluate prevention in flights lasting between 11 and 12 hours. The control group had no prophylaxis; the treatment group used Traveno stockings. Of the 83 included subjects in the stockings group and 82 in the control group (total 165), 146 subjects completed the study. Dropouts were due to low compliance or connection problems. Age/sex distribution were comparable. Of 75 subjects completing the study in the stockings group and 71 in the control group, none had thrombosis. The average level of edema at inclusion was comparable in the 2 groups (1.1). After the flight there was a score of 8.9 (2) in controls; in the stockings group the score was 2.56 (1.3) (p < 0.05). The control of edema and swelling with stockings even after 11 hours of flight was clear, considering both parametric (circumference, volume) and nonparametric (analogue scale lines) measurements. The tolerability of the stockings was very good and there were no complaints or side effects. In conclusion Sigvaris Traveno stockings are very effective in controlling edema in long-haul flights.     

Prevention of venous thrombosis and thrombophlebitis in long-haul flights with pycnogenol.

The aim of this study was to evaluate the occurrence of deep venous thrombosis (DVT) and superficial vein thrombosis (SVT) and its prophylaxis with an oral anti-edema and antithrombotic agent (Pycnogenol, Horphag, Research Management SA, Geneva, Switzerland) in long-haul flights, in subjects at moderate to high-risk of DVT and SVT. The study pre-included 244 pre-selected subjects; 211 were included (33 were excluded for several reasons due to logistic problems) and 198 completed the study; 13 subjects were lost for follow-up at the end of the flight, all for non-medical problems (i.e., for difficult connections). All subjects were scanned within 90 minutes before the flight and within 2 hours after disembarking. Subjects were supplemented with 100 mg Pycnogenol per capsule. Treatment subjects received two capsules between 2 and 3 hours before flights with 250 mL of water; two capsules were taken 6 hours later with 250 mL of water and one capsule the next day. The control group received comparable placebo at the same intervals. The flight duration was on average 8 hours and 15 minutes (SD 55 min) (range, 7.45-12.33). In the control group there were five thrombotic events (one DVT and four superficial thromboses) while only nonthrombotic, localized phlebitis was observed in the Pycnogenol group (5.15% vs. no events; p<0.025). The ITT (intention to treat) analysis detects 13 failures in the control group (eight lost to follow up + five thrombotic events) of 105 subjects (12.4%) vs. five failures (4.7%; all lost, no thrombotic events) in the treatment group (p<0.025). No unwanted effects were observed. In conclusion, this study indicates that Pycnogenol treatment was effective in decreasing the number of thrombotic events (DVT and SVT) in moderate-to-high risk subjects, during long-haul flights.     

Home therapy with LMWH in deep vein thrombosis: randomized study comparing single and double daily administrations

The aim of this study was to assess the effectiveness of low-molecular-weight heparin (LMWH) treatment of deep vein thrombosis (DVT) in terms of the evolution of thrombosis, the incidence of adverse events, and compliance with heparin treatment using 2 types of LMWH available on the market administered in therapeutic doses throughout the period of treatment (Nadroparin) or at therapeutic doses only during the first month of treatment followed by a prophylactic phase at half dose (Parnaparin). A randomized prospective study was carried out on patients under observation with a recent diagnosis of DVT. The objectives of the study were to confirm the effectiveness of therapy with LMWH in terms of prevention of the risk of thromboembolism, of relapse of DVT, and of hemorrhagic complications, and to complete an evaluation of venous recanalization and residual valve competence in the 2 groups of patients. From December 2002 to June 2005, we randomized a total of 91 patients (51 in the Parnaparin group and 40 in the Nadroparin group). Overall, there was 1 case of nonfatal pulmonary embolism (1.1%) at 7 days into therapy with LMWH. There were 3 cases (3.3%) of progression of thrombosis despite therapy with LMWH, 2 cases (5%) in the Nadroparin group, and 1 case (2%) in the Parnaparin group (P = NS), and after suspension of the therapy, there was 1 case of relapse of thrombosis. Three of the 4 thrombotic events occurred in patients with active neoplasia. Moreover, only 1 major hemorrhagic event (1.1%) required blood transfusion. The Doppler ultrasound in the follow-up showed a complete resolution of 56% of the vein thromboses at an average of 6.1 +/- 4.6 (mean +/- SD) months. Valve competence recovered in 65.9% of cases with no significant difference between the 2 heparin groups. Home treatment of sural and femoral-popliteal DVT using LMWH represents a safe and effective method in the prevention of pulmonary embolism and encourages the process of recanalization of the thrombosed vessel, especially in cases of sural and/or popliteal DVT. Administration can be carried out with the same degree of safety at the therapeutic dose throughout the period of treatment or can be halved after the first month of treatment. In patients with active neoplasia, treatment with oral anticoagulant therapy must be considered.     

Deep vein thrombosis in patients with multiple myeloma treated with thalidomide and chemotherapy: effects of prophylactic and therapeutic anticoagulation

A group of 256 newly diagnosed myeloma patients were enrolled in a phase III study that included 4 monthly cycles of induction chemotherapy and tandem transplant. All patients were randomized to either receive or not receive thalidomide. A total of 221 patients (86%) received no prophylactic anticoagulation (cohort I); 35 patients received low dose coumadin (cohort II). The incidence of deep vein thrombosis (DVT) was significantly higher in the thalidomide arm hazard ratio: 4.5; P < 0.0001). As low dose coumadin (1 mg/d) failed to decrease thrombotic complications in 35 patients (cohort II), low molecular weight heparin (LMWH, enoxaparin 40 mg s.c. q.d.) was instituted as DVT prophylaxis in the thalidomide-treated patients (n = 68) of the subsequent cohort (n = 130, cohort III). This intervention eliminated the difference in DVT incidence between the two arms (thalidomide and no thalidomide). Within cohorts I and II, 36 patients, in whom thalidomide was discontinued after experiencing a thrombotic episode during chemotherapy, subsequently resumed the drug on full anticoagulation; with a median follow-up of 22 months, DVT recurred in four patients (11%). After completing induction and tandem transplantation, 55 patients were re-exposed to thalidomide and chemotherapy during consolidation treatment. Thrombotic complications were observed in 4%. Our experience, although not based on a randomized study, suggests that the excess frequency of thrombosis in patients treated with chemotherapy and thalidomide can be safely reduced by the prophylactic use of LMWH. The rate of DVT recurrence observed in our study upon thalidomide resumption was sufficiently low to allow its continuation in patients who may benefit from this therapeutic intervention.     

Prevention of recurrent deep venous thrombosis with sulodexide: the SanVal registry

The aim of this study was to evaluate the prevention of recurrent deep vein thrombosis (R-DVT) with an oral antithrombotic agent (sulodexide) in moderate to high-risk subjects. A group of 405 patients was included into the multicenter registry. Both compression and an exercise program were used as well as a risk-factors control plan. After diagnosis of DVT, patients were treated with oral anticoagulants for 6 months. At the end of this period a coagulation study was made and patients started treatment with oral sulodexide capsules for a period of 24 months. The femoral, popliteal, tibial, and superficial veins were scanned with high-resolution ultrasound at inclusion;scans were repeated at 6, 12, 18, and 24 months. Of the 405 subjects included into the registry 178 in the control group (mean age 52.2; SD 11; M:F=90:88) and 189 in the treatment group (mean age 53.2; SD 10.3; M:F=93:96) completed the analysis period of 24 months. At 6 and 12 months the incidence of R-DVT was lower (p<0.05) in the treatment group. At 24 months the global incidence of R-DVT was 17.9% in the control group and 7.4% in the sulodexide group (p<0.05), 2.42 times lower than in controls. The 2 groups were comparable for age and sex distribution and for the localization of the thrombi at inclusion. Also the 2 groups of dropouts were comparable. In the control group there were 32 recurrent DVTs and 24 subjects lost to follow-up (total of 56) of 202 included subjects (27.7%) in comparison with 28 failures (14 recurrent DVTs and 14 lost subjects) of 203 subjects (13.8%) in the treatment group. This difference was statistically significant. In this analysis the incidence of DVT in controls was 2.07 times higher than in the treatment group subjects. In conclusion sulodexide was effective in reducing recurrent thrombotic events in high-risk subjects.     

Superficial thrombophlebitis of the legs: a randomized, controlled, follow-up study.

The aim of the present study was to evaluate the effects of different treatment plans (compression only, early surgery, low-dose subcutaneous heparin [LDSH], low-molecular-weight heparin [LMWH], and oral anticoagulant [OC] treatment) in the management of superficial thrombophlebitis (STP), by considering efficacy and costs in a 6-month, randomized, follow-up trial. Patients with STP, with large varicose veins without any suspected/documented systemic disorder, were included. Criteria for inclusion were as follows: presence of varicose veins; venous incompetence (by duplex); a tender, indurated cord along a superficial vein; and redness and heat in the affected area. All patients were ambulatory. Exclusion criteria were obesity, cardiovascular or neoplastic diseases, bone/joint disease, problems requiring immobilization, and age > 70 years. Patients with superficial thrombophlebitis without varicose veins and patients under treatment with drugs at referral were also excluded. Color duplex (CD) was used to detect concomitant deep vein thrombosis (DVT) and to evaluate the extension or reduction of STP at 3 and 6 months. Venography was not used. Of 562 patients included, 3.5% had had a recent DVT in the same limb affected by SVT and 2.1% in the contralateral limb. In six patients DVT was present in both limbs. These patients were treated with anticoagulants and excluded from the follow-up. After 3 and 6 months the incidence of STP extension was higher in the elastic compression and in the saphenous ligation groups (p < 0.05). There was no significant difference in DVT incidence at 3 months among the treatment groups. Stripping of the affected veins was associated with the lowest incidence of thrombus extension. The cost for compression alone was the lowest and the cost including LMWH was the highest. The average cost was 1,383 US$. However the highest social cost (lost working days, inactivity) was observed in subjects treated only with stockings.     

Venous thrombosis after long-haul flights

BACKGROUND: The risk for venous thromboembolism after long-haul flights represents a controversial issue. The aim of our study was to assess the incidence of venous thrombosis associated with long-haul flights in a prospective, controlled cohort study. METHODS: We included 964 passengers returning from long-haul flights (flight duration, > or =8 hours) and 1213 nontraveling control subjects. We excluded participants who were being treated with anticoagulant drugs or who used compression stockings. Main outcome measures were the incidence of ultrasonographically diagnosed thrombosis in the calf muscle and deep veins, symptomatic pulmonary embolism, and death. RESULTS: We diagnosed venous thrombotic events in 27 passengers (2.8%) and 12 controls (1.0%) (risk ratio [RR], 2.83; 95% confidence interval [CI], 1.46-5.49). Of these, 20 passengers (2.1%) and 10 controls (0.8%) presented with isolated calf muscle venous thrombosis (RR, 2.52; 95% CI, 1.20-5.26), whereas 7 passengers (0.7%) and 2 controls (0.2%) presented with deep venous thrombosis (RR, 4.40; 95% CI, 1.04-18.62). Symptomatic pulmonary embolism was diagnosed in 1 passenger with deep venous thrombosis (P =.44). All of these individuals had normal findings at baseline ultrasonography. Passengers with isolated calf muscle venous thrombosis or deep venous thrombosis had at least 1 risk factor for venous thrombosis (>45 years of age or elevated body mass index in 21 of 27 passengers). The follow-up after 4 weeks revealed no further venous thromboembolic event. CONCLUSIONS: Long-haul flights of 8 hours and longer double the risk for isolated calf muscle venous thrombosis. This translates into an increased risk for deep venous thrombosis as well. In our study, flight-associated thrombosis occurred exclusively in passengers with well-established risk factors for venous thrombosis.     

The LONFLIT4-Venoruton Study: a randomized trial--prophylaxis of flight-edema in venous patients

The aim of this independent study was to evaluate the protective effects, on the development of flight edema, of Venoruton. The study included patients with venous disease traveling in economy in long-haul flights (9 hours). Edema is a relevant aspect of long-haul flights affecting both patients with venous disease and normal subjects. Microcirculatory variations during flights cause a microangiopathy and biochemical and coagulation alterations. This condition may be defined as flight microangiopathy. A group of 203 subjects with chronic venous disease (uncomplicated varicose veins) at low-medium risk for DVT were contacted; 43 subjects were excluded for several nonmedical, travel-related problems or inconvenient evaluation time; the remaining 160 were randomized, after informed consent, into 2 groups to evaluate 2 prophylaxes in 7-8-hour, long-haul flights: The treatment group received Venoruton (hydroxyethyl rutosides) 1 g twice daily for 3 days (2 days before the flight and the day of the flight). The control group received comparable placebo. The edema score was based on the edema tester, ankle circumference, volume measurements, subjective swelling, and discomfort score. Items 1, 4, and 5 are based on an analogue scale line (1 to 10) directly defined by the subjects before and after the flights. Of the 160 included subjects 139 completed the study. Dropouts (21) were due to poor compliance, traveling, and/or connection problems (11 in the control group, 10 in the treatment group). Age and sex distribution were comparable in the 2 groups as were risk factors distributions. The level of edema at inclusion was comparable in the 2 groups of subjects. After the flight there was an average score of 7.2 (sd 2) in the control group, while in the Venoruton group the score was on average 3.2. (sd 1.1) (p < 0.05), 2.25 times lower than in the control group (p < 0.05). In the control group 89% of the subjects had an evident increase in ankle circumference and volume, which was clearly visible at inspection and associated with discomfort. In the Venoruton group edema was clearly present in 12% of subjects (associated with discomfort between 5 and 7 on the analogue scale line) and it was mild-moderate, not associated with symptoms (pain, discomfort between 2 and 4 on the analogue scale line). Therefore, the control of flight edema with Venoruton was clear both considering parametric data (circumference and volume) and nonparametric (analogue scale lines) measurements. The combined evaluation of the edema score is significantly favorable for patients treated with Venoruton. No deep vein thrombosis or superficial vein thrombosis was observed in this study.     

Stent thrombosis in patients treated with thienopyridines: clinical description of 10 cases

Subacute stent thrombosis (SAST) is a major thrombotic complication of coronary stenting. Its occurrence has been substantially reduced by thienopyridine treatment. However, information on clinical profile of patients with SAST in clopidogrel era is limited. In order to define the incidence and factors predisposing to stent thrombosis, we analyzed the computerized angiographic database of three interventional cardiology centers. Out of a total number of 5903 percutaneous coronary interventions (PCIs) with stent implantation, we found 10 patients with SAST (0.17%). The indication for PCI was usually an early invasive approach (90%) during an acute coronary syndrome. All patients were treated with an apparently optimal antithrombotic regimen (90% received heparin or LMWH and 70% received IIb/IIIa receptor inhibitors and all given aspirin). In each of the patients, we could identify high-risk angiographic findings. SAST presentation was always clinically significant with definite myocardial infarction in 100% of cases. 80% of cases occurred during the first six days post PCI. Two patients had a recurrent event. Finally, despite earlier reports of atorvastatin-mediated inhibition of clopidogrel activation we did not find any patient with SAST taking both drugs. Thus, patients with stent thrombosis during thienopyridine treatment usually exhibit high-risk angiographic features. Prospective studies should be performed to elucidate drug interactions that may reduce clopidogrel efficacy and contribute to stent thrombosis. (Int J Cardiovasc Intervent 2004; 6: 160-164)     

Deferment of objective assessment of deep vein thrombosis and pulmonary embolism without increased risk of thrombosis: a practical approach based on the pretest clinical model, D-dimer testing, and the use of low-molecular-weight heparins

BACKGROUND: Treatment of patients with suspected deep vein thrombosis (DVT) or pulmonary embolism (PE) is problematic if diagnostic imaging is not immediately available. Pretest clinical probability (PCP) and D-dimer assessment can be used to identify patients for whom empirical protective anticoagulation is indicated. To evaluate whether PCP and D-dimer assessment, together with the use of low-molecular-weight heparins (LMWHs), allow objective appraisal of DVT and PE to be deferred for up to 72 hours, patients with suspected DVT and PE were prospectively examined. METHODS: Patients identified with a high PCP or a moderate PCP with positive D-dimer test results received a protective full-dose treatment of LMWH; the remaining patients were discharged without anticoagulant administration. However, all patients were scheduled to undergo objective tests for DVT or PE within 72 hours. Standard antithrombotic therapy was administered when deferred diagnostic tests confirmed venous thromboembolism. RESULTS: In total, 409 consecutive patients with suspected DVT and 124 with suspected PE were included in this study. A total of 23.8% (95% confidence interval [CI], 20.3%-27.3%) of patients had confirmed venous thromboembolism. At the short-term follow-up (72 hours), only a single thromboembolic event (0.2%; upper 95% CI, 0.6%) had occurred, whereas at the 3-month follow-up, 5 events (1.2%; 95% CI, 0.2%-2.1%) had occurred in patients in whom diagnosis of DVT or PE had previously been ruled out. None of the patients had major bleeding events. Ninety percent of patients were treated as outpatients. CONCLUSION: Our study demonstrates that this approach allows the safe deferral of diagnostic procedures for DVT and PE for up to 72 hours.     

Low molecular weight heparin and aspirin for prevention of deep vein thrombosisafter orthopaedic surgery: a systematic review and meta-analysis

Journal of Thrombosis and Thrombolysis - To comprehensively evaluate the clinical effects of low molecular weight heparin (LMWH) and aspirin for deep vein thrombosis (DVT) patients after...     

Use of high intensity adjusted dose low molecular weight heparin in women with mechanical heart valves during pregnancy: a single-center experience

The use of standard dose low molecular weight heparin (LMWH) to anticoagulate women with mechanical valves in pregnancy is associated with morbidity and mortality. We conducted a prospective audit of the use of adjusted dose high intensity LMWH in 12 pregnancies in 11 women with prosthetic heart valves. LMWH ± low-dose aspirin was started at therapeutic-dose with monitoring of anti-Xa levels to achieve a target level of 1.0–1.2 IU/mL (0.8–1.2 in the first 3/12 pregnancies). This necessitated a mean increase in the dose of LMWH of 54.4% (SD±33.2) over initial dose. Eleven of 12 pregnancies resulted in live births, with one intrauterine fetal death at 37 weeks. One non-fatal valve thrombosis occurred at 26 weeks gestation associated with subtherapeutic anti-Xa levels. Three patients experienced major bleeding. This regime provides a therapeutic option for women with mechanical heart valves during pregnancy, provided anti-Xa levels are kept within the target range. These patients require close surveillance for bleeding and thrombotic complications within a multi-disciplinary setting.     

Superficial thrombophlebitis and low-molecular-weight heparins

The current status of superficial thrombophlebitis, including incidence, diagnosis, and management, are reviewed. Treatment options are assessed in the light of data from the main studies reported in the literature. These include compression, ambulation, and nonsteroidal antiinflammatory agents and surgical management with high saphenous ligation (with or without saphenous vein stripping) with or without anticoagulants, ranging from aspirin, unfractionated heparin, warfarin, and low-molecular-weight heparin (LMWH). The advantage of the surgical approach is that by ligation with or without stripping of the superficial veins the underlying pathesis (i.e., varicose veins) is also eradicated. In the presence of deep venous thrombosis (DVT), surgery could be combined with anticoagulants. The extensive current literature for DVT treatment shows that the LMWHs are at least as effective and safe as the unfractionated heparins. On this basis, one could reasonably recommend LMWH for the treatment of superficial thrombophlebitis with involvement of the deep veins. Pentasaccharide, a drug that has been recently explored for the prophylaxis and treatment of DVT could be another option. However, there are as yet no data for recommended dosages or duration of treatment for the latter two options.     

Review: Fondaparinux reduces VTE and recurrence in superficial thrombophlebitis of the leg

QUESTION What are the efficacy and safety of treatments for superficial thrombophlebitis (ST) of the leg? REVIEW SCOPE Included studies compared topical, medical, and surgical treatments for ST of the leg with placebo, another treatment, or no treatment in patients diagnosed on the basis of signs and symptoms, clinical examination, and ultrasonography of the lower limbs. Exclusion criteria included concomitant deep venous thrombosis (DVT) identified on ultrasonography. Outcomes included objectively confirmed symptomatic pulmonary embolism (PE) or DVT, extension or recurrence of ST, and treatment side effects. Symptoms were not reported consistently and are not reported in this abstract. REVIEW METHODS Cochrane Peripheral Vascular Diseases Group Specialised Register, which includes search results from MEDLINE, EMBASE/Excerpta Medica, CINAHL, and AMED databases and hand-searches of journals (to Nov 2011); Cochrane Central Register of Controlled Trials (2011, Issue 4); conference proceedings; and reference lists were searched for randomized controlled trials (RCTs). Experts were contacted. 26 RCTs (n =?5521, mean age range 39 to 63 y, 43% to 79% women) met inclusion criteria and evaluated ≥?1 treatment type: 11 evaluated low-molecular-weight heparin (LMWH) (n =?1651); 8 oral, intramuscular, or IV treatments (n =?1139); 7 topical agents (n =?296); 5 nonsteroidal antiinflammatory drugs (NSAIDs) (n =?710); 3 surgery (n =?705); and 1 fondaparinux (n =?3002). 3 RCTs had adequate allocation concealment, 14 used a double-blind design, and 7 did intention-to-treat analyses. MAIN RESULTS The main results for fondaparinux and LMWH are in the Table. Limited data were reported for other treatment comparisons. CONCLUSIONS In patients with superficial thrombophlebitis of the leg, prophylactic doses of fondaparinux reduce venous thromboembolism and extension or recurrence of disease without evidence of increasing major bleeding. Insufficient high-quality evidence exists to evaluate the effect of low-molecular-weight heparin or other treatments on patient-important outcomes.Treatments for superficial thrombophlebitis (ST) of the leg*TreatmentsNumber of trials (n)OutcomesSelected findingsFondaparinux vs placebo1 (3002)Symptomatic DVT or PE0.20% vs 1.3%; RRR 85%, 95% CI 50 to 96ST extension0.27% vs 3.4%; RRR 92%, CI 78 to 97ST recurrence0.33% vs 1.6%; RRR 79%, CI 46 to 92Major bleeding0.07% vs 0.07%; RRR 1%, CI -1486 to 94LMWH?11 (1651)VTENo difference in 10 RCTs; NR in 1 RCT.ST extension or recurrence1 RCT, n =?328. Prophylactic LMWH 12% vs placebo 29%; RRR 60%, CI 28 to 78. Therapeutic LMWH 12% vs placebo 29%; RRR 58%, CI 25 to 77.1 RCT, n =?225. Prophylactic LMWH + ECS 1.3% vs ECS alone 17%; RRR 92%, CI 41 to 99. Prophylactic UFH + ECS 2.8% vs ECS alone 17%; RRR 83%, CI 28 to 96No difference in 5 RCTs; NR in 4 RCTs.Major bleeding0 events reported in 6 RCTs; NR in 5 RCTs.*DVT = deep venous thrombosis; ECS = elastic compression stocking; LMWH = low-molecular-weight heparin; NR = not reported; PE = pulmonary embolism; RCT = randomized controlled trial; UFH = unfractionated heparin; VTE = venous thromboembolism; other abbreviations defined in Glossary.?Comparisons included placebo, ECSs, nonsteroidal antiinflammatory drugs, defibrotide, venoruton, topical heparin spray gel, surgery, or different heparin doses.     

Outpatient management of DVT using low molecular weight heparin and a hospital outreach service

In recent years there have been several studies comparing the efficacy and safety of low molecular weight (LMW) and unfractionated heparin for the treatment of deep venous thrombosis (DVT), showing them in the clinical trial setting to be equal in these regards. LMWH has the advantage of once daily subcutaneous injection and daily monitoring of levels is not usually required. This has led many centres to develop outpatient treatment strategies for these patients but evidence for the safety of this approach is scarce. In 1997 we developed a hospital outreach service for the treatment of patients with DVT and, in a retrospective study, have compared the outcome in 172 patients treated at home with 172 age, sex and thrombotic risk factor matched inpatients treated at our institution with unfractionated heparin. Five patients in the home treatment group suffered a haemorrhagic event, compared with six patients in the hospital group. One patient in the home treatment group had a recurrent DVT within the first 3 months of treatment; in the hospital-treated group, six patients had recurrent DVTs and nine developed pulmonary emboli. At 3 months, there were three deaths in the home treatment group, compared with five deaths in the hospital group. There was no difference in re-admission rate at 3 months: 23 in the home treatment group, 24 in the hospital-treated group. Average length of hospital stay for the home-treatment group was 2.1 days and 12 days for the hospital group. Warfarin control was found to be significantly better in those patients treated at home, and only 18% of patients treated in hospital received heparin according to hospital guidelines. In conclusion, outpatient management of patients with DVT using LMWH is as safe as hospitalization and continuous infusion of unfractionated heparin. The complication rate was lower in the home treatment group and, in particular, the incidence of recurrent thrombosis was significantly less in the home treatment group. In addition, warfarin control was better when managed by specialist nurses. Patients expressed a preference for home treatment.     

Air Travel and Venous Thromboembolism: A Systematic Review

CONTEXT: Despite multiple attempts to document and quantify the danger of venous thromboembolism (VTE) following prolonged travel, there is still uncertainty about the magnitude of risk and what can be done to lower it. OBJECTIVES: To review the methodologic strength of the literature, estimate the risk of travel-related VTE, evaluate the efficacy of preventive treatments, and develop evidence-based recommendations for practice. DATA SOURCES: Studies identified from MEDLINE from 1966 through December 2005, supplemented by a review of the Cochrane Central Registry of Controlled Trials, the Database of Abstracts of Reviews of Effects, and relevant bibliographies. STUDY SELECTION: We included all clinical studies that either reported primary data concerning travel as a risk factor for VTE or tested preventive measures for travel-related VTE. DATA EXTRACTION AND ANALYSIS: Two reviewers reviewed each study independently to assess inclusion criteria, classify research design, and rate methodologic features. The effect of methodologic differences, VTE risk, and travel duration on VTE rate was evaluated using a logistic regression model. DATA SYNTHESIS: Twenty-four published reports, totaling 25 studies, met inclusion criteria (6 case-control studies, 10 cohort studies, and 9 randomized controlled trials). Method of screening for VTE [screening ultrasound compared to usual clinical care, odds ratio (OR) 390], outcome measure [all VTE compared to pulmonary embolism (PE) only, OR 21], duration of travel (<6 hours compared to 6-8 hours, OR 0.011), and clinical risk ("higher" risk travelers compared to "lower," OR 3.6) were significantly related to VTE rate. Clinical VTE after prolonged travel is rare [27 PE per million flights diagnosed through usual clinical care, 0.05% symptomatic deep venous thrombosis (DVT) diagnosed through screening ultrasounds], but asymptomatic thrombi of uncertain clinical significance are more common. Graduated compression stockings prevented travel-related VTE (P < 0.05 in 4 of 6 studies), aspirin did not, and low-molecular-weight heparin (LMWH) showed a trend toward efficacy in one study. CONCLUSIONS: All travelers, regardless of VTE risk, should avoid dehydration and frequently exercise leg muscles. Travelers on a flight of less than 6 hours and those with no known risk factors for VTE, regardless of the duration of the flight, do not need DVT prophylaxis. Travelers with 1 or more risk factors for VTE should consider graduated compression stockings and/or LMWH for flights longer than 6 hours.