Two years outcome of isolated distal deep vein thrombosis

Recurrence in isolated distal DVT after anticoagulation: a systematic review and meta-analysis of axial and muscular venous thrombosis

OBJECTIVE

To identify recurrent venous thromboembolism (VTE) after discontinuation of anticoagulation in patients with isolated distal deep vein thrombosis based on its anatomic localization (axial or muscular veins).

METHODS

Data were sourced from PubMed, Embase, Cochrane Library, Web of Science, and ClinicalTrials.gov databases in the time period up to October 2023. The study followed PRISMA guidelines using a registered protocol (CRD42023443029). Studies reporting recurrent VTE in patients with axial or muscular DVT were included in the analysis.

RESULTS

Five studies with a total of 1,403 participants were evaluated. The results showed a pooled odds ratio of 1.12 (95% confidence interval 0.77-1.63) between axial and muscular DVT. Heterogeneity was low (I2 = 0%, p = 0.91) and there was no significant difference in the rate of recurrent VTE between axial and muscular DVT in each subgroup.

CONCLUSIONS

Muscular and axial DVT showed comparable recurrent VTE rates after anticoagulation. However, uncertainties regarding the possibility of recurrence affecting the popliteal vein or resulting in pulmonary embolism following muscular DVT anticoagulation persisted. Randomized trials in patients with isolated distal DVT are still needed to clarify its prognosis for different anatomical thrombus locations.

Exploratory rivaroxaban trial for isolated calf deep vein thrombosis with a risk factor of thrombosis extension: an open-label, multicenter, randomized controlled trial

Background

Limited evidence exists regarding the incidence of recurrent venous thromboembolism (VTE) in patients diagnosed with isolated distal deep vein thrombosis (DVT) who are at risk of thrombosis extension whether they receive anticoagulation therapy or not.

Objectives

The study aimed to investigate the incidence of recurrent VTE and the impact of rivaroxaban in this patient population.

Methods

This open-label, exploratory, and randomized controlled trial was conducted at 7 centers in Japan between April 2019 and April 2022. Adult patients with isolated distal DVT at risk of thrombosis extension received either rivaroxaban combined with physical therapy or physical therapy alone for 90 days. Whole-leg ultrasound was performed at 14 and 90 days. We assessed a composite outcome of symptomatic or asymptomatic proximal DVT or symptomatic pulmonary embolism as the primary outcome until the end of the treatment period using an intention-to-treat analysis. Major bleeding was evaluated as a key secondary outcome.

Results

Out of 90 enrolled patients, 3 were excluded due to withdrawal of consent; therefore, we analyzed 87 participants. The rivaroxaban group (n = 42) reported no primary outcomes (0%; 95% CI, 0.0%-8.4%), whereas the physical therapy group (n = 45) had 2 cases of symptomatic proximal DVT (4.4%; 95% CI, 0.5%-15.1%). Major bleeding events occurred in 4 patients in the rivaroxaban group (9.5%; 95% CI, 2.7%-22.6%), whereas no events occurred in the physical therapy group (0%; 95% CI, 0%-7.9%).

Conclusion

Preliminary data suggest that rivaroxaban may reduce the risk of VTE recurrence among this patient subset, albeit with an increased incidence of bleeding events.

Management of isolated distal deep vein thrombosis

Isolated distal deep vein thrombosis (DVT) represents up to 50% of all lower limb DVT in ultrasound series and is a frequent medical condition, which management is not well established. Data arising from registries and non-randomized studies suggest that most distal DVTs do not extend to the proximal veins and have an uneventful follow-up when left untreated. This data had some impact on international recommendations like the American College of Chest Physicians (ACCP), whose last version stated that ultrasound surveillance might be an option for selected low-risk patients. However, robust data arising from randomized studies are scarce. Indeed, only seven randomized trials assessing the need for anticoagulation for calf DVT have been published. Many of these trials had an open-label design and were affected by methodological limitations. When considering randomized placebo-controlled trials, one included low-risk patients and was hampered by a limited statistical power (CACTUS study). Nevertheless, data from this trial tend to confirm that the use of therapeutic anticoagulation in low-risk patients with symptomatic calf DVT is not superior to placebo in reducing VTE but is associated with a higher risk of bleeding. A second randomized placebo-controlled trial did not assess the necessity of anticoagulant treatment but rather the long-term risk of recurrence and compared 6 weeks versus 12 weeks of treatment with rivaroxaban (RIDTS study). Finally, the last available randomized trial compared a 3-month versus a 12-month edoxaban treatment in patients with cancer and mainly asymptomatic distal DVT, detected by systematic compression ultrasonography. Overall, available data suggest that the use of therapeutic anticoagulation in low-risk patients with symptomatic calf DVT is not superior to placebo in reducing VTE. High risk patients (previous VTE, active cancer, inpatients) might benefit from a course of anticoagulant treatment. However, the optimal anticoagulant intensity and duration are uncertain and further studies are needed.

Comparison of clinical outcomes among patients with isolated axial vs muscular calf vein thrombosis: A systematic review and meta-analysis

OBJECTIVE

Thrombi in the axial calf veins have quite different anatomical and physiological characteristics from that in the muscular calf veins, but their treatment was usually addressed in the same manner. We performed a meta-analysis of randomized and cohort studies to compare clinical outcomes among patients with isolated axial vs muscular calf deep vein thrombosis (DVT).

METHODS

Recurrent venous thromboembolism (VTE) was selected as the primary outcome. Resolution, proximal propagation of calf DVT, pulmonary embolism (PE), major bleeds, and clinically relevant non-major bleeds were separately analyzed as secondary outcomes. Data were pooled and compared with risk ratio (RR) and 95% confidence interval (CI).

RESULTS

Thirteen studies, consisting of 4889 patients, met the inclusion criteria and were included for analysis. A greater rate of recurrent VTE (FE model: RR, 1.23; 95% CI, 1.00-1.53; I2 = 29%), resolution (FE model: RR, 1.32; 95% CI, 1.01-1.72; I2 = 31%), proximal propagation (FE model: RR, 1.63; 95% CI, 1.10-2.41; I2 = 40%), and PE (FE model: RR, 2.79; 95% CI, 1.31-5.95; I2 = 0%) in the axial group compared with the muscular group. There was no difference in the pooled estimates for major bleeds (FE model: RR, 1.09; 95% CI, 0.61-1.95; I2 = 0%), and clinically relevant non-major bleeds (FE model: RR, 1.80; 95% CI, 0.93-3.48) in the axial and muscular arms.

CONCLUSIONS

Patients with calf DVT limited to muscular veins might have a lower rate of recurrent VTE, resolution, proximal propagation, and PE vs those with axial calf vein involvement and exhibited similar safety outcomes.

Edoxaban for 12 Months Versus 3 Months in Patients With Cancer With Isolated Distal Deep Vein Thrombosis (ONCO DVT Study): An Open-Label, Multicenter, Randomized Clinical Trial

BACKGROUND

The optimal duration of anticoagulation therapy for isolated distal deep vein thrombosis in patients with cancer is clinically relevant, but the evidence is lacking. The prolonged anticoagulation therapy could have a potential benefit for prevention of thrombotic events; however, it could also increase the risk of bleeding.

METHODS

In a multicenter, open-label, adjudicator-blinded, randomized clinical trial at 60 institutions in Japan, we randomly assigned patients with cancer with isolated distal deep vein thrombosis, in a 1-to-1 ratio, to receive either a 12-month or 3-month edoxaban treatment. The primary end point was a composite of a symptomatic recurrent venous thromboembolism (VTE) or VTE-related death at 12 months. The major secondary end point was major bleeding at 12 months, according to the criteria of the International Society on Thrombosis and Haemostasis. The primary hypothesis was that a 12-month edoxaban treatment was superior to a 3-month edoxaban treatment with respect to the primary end point.

RESULTS

From April 2019 through June 2022, 604 patients were randomized, and after excluding 3 patients who withdrew consent, 601 patients were included in the intention-to-treat population: 296 patients in the 12-month edoxaban group and 305 patients in the 3-month edoxaban group. The mean age was 70.8 years, 28% of the patients were men, and 20% of the patients had symptoms of deep vein thrombosis at baseline. The primary end point of a symptomatic recurrent VTE event or VTE-related death occurred in 3 of the 296 patients (1.0%) in the 12-month edoxaban group and in 22 of the 305 patients (7.2%) in the 3-month edoxaban group (odds ratio, 0.13; 95% CI, 0.03-0.44). The major secondary end point of major bleeding occurred in 28 of the 296 patients (9.5%) in the 12-month edoxaban group and in 22 of the 305 patients (7.2%) in the 3-month edoxaban group (odds ratio, 1.34; 95% CI, 0.75-2.41). The prespecified subgroups did not affect the estimates on the primary end point.

CONCLUSIONS

In patients with cancer with isolated distal deep vein thrombosis, 12 months was superior to 3 months for an edoxaban treatment with respect to the composite outcome of a symptomatic recurrent VTE or VTE-related death.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03895502.

Incidence of bleeding and recurrence in isolated distal deep vein thrombosis: findings from the Venous Thrombosis Registry in Østfold Hospital

BACKGROUND

Isolated distal deep vein thrombosis (IDDVT) is a common presentation of deep vein thrombosis. There are limited data on the long-term risk of recurrence after IDDVT.

OBJECTIVES

We aimed to determine the short- and long-term incidence of venous thrombosis (VTE) recurrence after cessation of anticoagulation and the 3-month incidence of bleeding during anticoagulant treatment in patients with IDDVT.

METHODS

Between January 2005 and May 2020, 475 patients with IDDVT and without active cancer were identified from the Venous Thrombosis Registry in Østfold Hospital, which is an ongoing registry of consecutive patients with VTE at Østfold Hospital, Norway. Major and clinically relevant, nonmajor bleeding as well as recurrent VTE were registered, and the cumulative incidences of these events were assessed.

RESULTS

The median age of the patients was 59 years (IQR, 48-72 years), 243 (51%) patients were women, and 175 events (36.8%) were classified as unprovoked. The 1-, 5-, and 10-year cumulative incidences of recurrent VTE were 5.6% (95% CI, 3.7-8.4), 14.7% (95% CI, 11.1-19.4), and 27.2% (95% CI, 21.1-34.5), respectively. The recurrence rates were higher for unprovoked IDDVT than for provoked IDDVT. Among the recurrent events, 18 (29%) were pulmonary embolisms and 21 (33%) were proximal deep vein thromboses. The 3-month cumulative incidence of major bleeding was 1.5% (95% CI, 0.7-3.1) overall and 0.8% (95% CI, 0.2-3.1) when restricted to patients treated with direct oral anticoagulants.

CONCLUSION

Despite initial treatment, the long-term risk of VTE recurrence after first-time IDDVT is high. The bleeding rates during anticoagulation, particularly with direct oral anticoagulants, were acceptably low.

Rivaroxaban treatment for six weeks versus three months in patients with symptomatic isolated distal deep vein thrombosis: randomised controlled trial

OBJECTIVE

To compare two different treatment durations of rivaroxaban in patients with symptomatic isolated distal deep vein thrombosis (DVT).

DESIGN

Randomised, double blind, placebo controlled clinical trial.

SETTING

28 outpatient clinics specialising in venous thromboembolism.

PARTICIPANTS

402 adults (≥18 years) with symptomatic isolated distal DVT.

INTERVENTIONS

After receiving standard dose rivaroxaban for six weeks, participants were randomly assigned to receive rivaroxaban 20 mg or placebo once daily for an additional six weeks. Follow-up was for 24 months from study inclusion.

MAIN OUTCOMES MEASURES

The primary efficacy outcome was recurrent venous thromboembolism during follow-up after randomisation, defined as the composite of progression of isolated distal DVT, recurrent isolated distal DVT, proximal DVT, symptomatic pulmonary embolism, or fatal pulmonary embolism. The primary safety outcome was major bleeding after randomisation until two days from the last dose of rivaroxaban or placebo. An independent committee adjudicated the outcomes.

RESULTS

200 adults were randomised to receive additional rivaroxaban treatment and 202 to receive placebo. Isolated distal DVT was unprovoked in 81 (40%) and 86 (43%) patients, respectively. The primary efficacy outcome occurred in 23 (11%) patients in the rivaroxaban arm and 39 (19%) in the placebo arm (relative risk 0.59, 95% confidence interval 0.36 to 0.95; P=0.03, number needed to treat 13, 95% confidence interval 7 to 126). Recurrent isolated distal DVT occurred in 16 (8%) patients in the rivaroxaban arm and 31 (15%) in the placebo arm (P=0.02). Proximal DVT or pulmonary embolism occurred in seven (3%) patients in the rivaroxaban arm and eight (4%) in the placebo arm (P=0.80). No major bleeding events occurred.

CONCLUSIONS

Rivaroxaban administered for six additional weeks in patients with isolated distal DVT who had an uneventful six week treatment course reduces the risk of recurrent venous thromboembolism, mainly recurrent isolated distal DVT, over a two year follow-up without increasing the risk of haemorrhage.

TRIAL REGISTRATION

EudraCT 2016-000958-36; ClinicalTrials.gov NCT02722447.

Obesity as a Risk Factor for Venous Thromboembolism Recurrence: A Systematic Review

Background and Objectives: Venous thromboembolism (VTE) encompasses Deep Venous Thrombosis (DVT) and Pulmonary Embolism (PE). The duration of anticoagulant therapy following a VTE event partly relies on the risk of recurrent VTE which depends on the clinical setting where VTE occurred and the VTE risk factors present. Obesity is considered a minor risk factor and studies in the literature have provided conflicting results on whether obesity influences the development of recurrences. The aim of the present study is to assess the effect of obesity on VTE recurrence in patients that suffered from a previous VTE event. Materials and Methods: We conducted systematic research for English language studies in Medline, Scopus and ProQuest databases in order to identify publications that assess the risk of VTE recurrence in obesity. Inclusion criteria were: 1. Diagnosis of VTE, 2. Definition of obesity as a body mass index ≥30 kg/m², 3. Report of the risk of obesity on VTE recurrence, 4. Adult human population. We did not include case reports, review studies or studies that assessed other forms of thrombosis and/or used other definitions of obesity. We used the Newcastle-Ottawa scale to address the quality of the studies. Results: Twenty studies were included in the analysis, of which 11 where prospective cohort studies, 6 were retrospective cohort studies, 1 was a cross-sectional study, and 2 were post-hoc analysis of randomized clinical trials. Obesity was significantly associated with recurrences in 9 studies and in 3 of them the association was significant only in females. Conclusions: There is heterogeneity between the studies both in their design and results, therefore the effect of obesity on VTE recurrence cannot be adequately estimated. Future randomized clinical studies with appropriately selected population are needed in order to streamline the effect of obesity on VTE recurrence.

Clinical presentation of isolated calf deep vein thrombosis in inpatients and prevalence of associated pulmonary embolism

OBJECTIVE

There is a controversy over the clinical significance and optimal treatment for isolated calf DVT. This study aimed to investigate the clinical presentation of isolated calf deep vein thrombosis (DVT) and the association of isolated calf DVT with pulmonary embolism (PE) in inpatients.

METHODS

A total of 1435 hospitalized patients underwent whole-leg duplex ultrasound between January 2018 and June 2020. Among them, 135 were diagnosed with isolated calf vein DVT.

RESULTS

The soleal vein was the most frequently involved (52.6%). Thrombus was detected only in axial veins in 57 patients (42.2%), muscular veins in 46 patients (34.4%), and in both axial and muscular veins in 32 patients (23.7%). Of the 135 patients, 44 patients (32.6%) had underwent recent orthopedic surgery, 31 patients (23.0%) had active cancer, and 22 patients (16.3%) had a history of recent stroke. The reasons for duplex ultrasound were leg edema and/or pain in 57 patients (42.2%), diagnosis of PE in 33 (24.4%), and elevated D-dimer level in 27 patients (20.0%). Sixteen patients (11.9%) were diagnosed as incidental findings on imaging studies for other purposes. Ninety-six patients (71.1%) received anticoagulation therapy. Concurrent PE was diagnosed in 45 patients (33.3%) and 14 patients had lesions in the main pulmonary artery. Among 45 patients with concurrent PE, 35 patients were diagnosed without leg edema and/or pain. Recurrent VTE was observed in four patients (3.0%) with a mean follow-up of 15.5±12.7 months.

CONCLUSIONS

Isolated calf DVT was associated with a high prevalence of PE in hospitalized patients. Patients with isolated calf DVT even without leg edema and/or pain may have concurrent PE. Anticoagulation therapy should be considered for isolated calf DVT in inpatients. The muscular veins were frequently involved, thus should be thoroughly evaluated and imaged.

Risk Factors and Anticoagulation Therapy in Patients With Isolated Distal Deep Vein Thrombosis in the Early Post-operative Period After Thoracic Surgery

Background: Isolated distal deep vein thrombosis (IDDVT) accounts for ~50% of all patients diagnosed with deep venous thrombosis (DVT), but the diagnosis and optimal management of IDDVT remains unclear and controversial. The aim of this study was to explore potential risk factors and predictors of IDDVT, and to evaluate different strategies of anticoagulation therapy.

Methods: A total of 310 consecutive patients after thoracic surgery, who underwent whole-leg ultrasonography as well as routine measurements of D-dimer levels before and after surgery were evaluated. The general clinical data, anticoagulant therapy, pre- and postoperative D-dimer levels were collected. Differences between IDDVT, DVT and non-DVT groups were calculated. Logistic regression analysis was used to analyze risk factors of postoperative IDDVT.

Results: Age and postoperative D-dimer levels were significantly higher in IDDVT group than in non DVT group (p = 0.0053 and p < 0.001, respectively). Logistic regression analysis showed that postoperative D-dimer level was a significant independent predictor of IDDVT even when adjusted for age and operation method (p = 0.0003). There were no significant side effects associated with both full-dose and half-dose anticoagulation regimens. Half-dose therapy was associated with a significant decrease in the requirement for anticoagulation medications after discharge (p = 0.0002).

Conclusion: Age and D-dimer levels after surgery are strong predictors of IDDVT following thoracic surgery. Half-dose therapeutic anticoagulation has the same efficiency in preventing IDDVT progression, is not associated with any additional risks of adverse effects compared to a full-dose regimen, and may be adopted for treating IDDVT patients after thoracic surgery.

A nomogram based on easily obtainable parameters for distal deep venous thrombosis in patients after acute stroke

OBJECTIVES

To develop and validate a nomogram to predict the probability of distal deep venous thrombosis (DVT) within first 14 days of stroke onset in patients by using easily obtainable parameters.

METHODS

This is a retrospective study. The presence of distal DVT was evaluated using ultrasonography within the first 14 days. Data were randomly assigned to either a modelling data set or a validation data set. Univariable and multivariate logistic regression analysis was used to determine risk scores to predict distal DVT in the modelling data set, and nomogram and calibration curve were constructed by R project.

RESULTS

A total of 1620 patients with acute stroke were enrolled in the study. The multivariate analysis revealed that the old age, female gender, haemorrhagic stroke, coronary heart disease, lower limb weakness, a low serum albumin level, and a high D-dimer level are highly predictive of 14-day risk of distal DVT. The AUC of the nomogram to predict the 14-day risk of distal DVT was 0.785 (95% CI, 0.742-0.827) and 0.813 (0.766-0.860) for the modelling cohort and external validation cohort, respectively. Moreover, the calibration of the nomogram showed a nonsignificant Hosmer-Lemeshow test statistic in the modelling (P = 0.876) and validation (P = 0.802) sets. With respect to decision curve analyses, the nomogram exhibited preferable net benefit gains than the staging system across a wide range of threshold probabilities.

CONCLUSION

The established nomogram displayed a superior performance in terms of predictive accuracy, discrimination capability, and clinical utility, may be helpful for clinicians to identify high-risk groups of distal DVT.

Literature review of distal deep vein thrombosis

OBJECTIVE

Although distal deep vein thrombosis (DDVT) has been more frequently diagnosed with the availability of better ultrasound imaging quality, the data on the best method to manage DDVT have been conflicting. The aim of the present review was to summarize the current and evidence-based recommendations for the diagnosis and management of DDVT and to provide a summary of the most recent societal guideline recommendations.

METHODS

A literature review of DDVT was performed. The PubMed databases were queried for articles on the epidemiology, risk factors, diagnosis, and management of DDVT.

RESULTS

The prevalence of isolated DDVT has been reported in a broad range. The reported risk factors include older age, active malignancy, a low degree of mobility, acute infection, and atrial fibrillation. With more evidence, anticoagulation therapy was found to be associated with a reduced risk of recurrent venous thromboembolism (VTE) and/or thrombus propagation compared with conservative management. However, anticoagulation was associated with an increased risk of bleeding in a number of studies. The rate of VTE recurrence ranged from 7% to 23% during a follow-up period ranging from 3 months to 8 years. The significant risk factors for VTE recurrence included cancer, older age, an unprovoked event, and inpatient status.

CONCLUSIONS

Few studies have addressed the diagnosis and management of DDVT. Further research is needed to standardize the best approach to diagnose and treat DDVT.

Calf vein thrombosis outcomes comparing patients with and without cancer

Distal or calf deep vein thrombosis (DVT) are said to have low rates of propagation, embolization, and recurrence. The objective of this study was to determine outcomes among cancer patients with calf DVT compared to those without cancer. Consecutive patients with ultrasound confirmed acute calf DVT (3/1/2013-8/10/2019) were assessed for venous thromboembolism (VTE) recurrence and bleeding outcomes compared by cancer status. There were 830 patients with isolated calf DVT; 243 with cancer and 587 without cancer. Cancer patients were older (65.9 ± 11.4 vs. 62.0 ± 15.9 years; p = 0.006), with less frequent recent hospitalization (31.7% vs. 48.0%; p < 0.001), surgery (30.0% vs. 38.0%; p = 0.03), or trauma (3.7% vs. 19.9%; p < 0.001). The four most common cancers included hematologic malignancies (20.6%), lung (11.5%), gastrointestinal (10.3%), and ovarian/GYN (9.1%). Nearly half of patients had metastatic disease (43.8%) and 57% were receiving chemotherapy. VTE recurrence rates were similar for patients with (7.1%) and without cancer (4.0%; p = 0.105). Major bleeding (6.3% vs. 2.3%; p = 0.007) were greater for cancer patients while clinical relevant non major bleeding rates did not differ (7.1% vs. 4.6%; p = 0.159). In this retrospective analysis, cancer patients with calf DVT have similar rates of VTE recurrence but higher major bleeding outcomes compared to patients without cancer.

Calf deep vein thrombosis: frequency, therapeutic management, early outcomes and all-causes mortality in a cohort of hospitalized patients

BACKGROUND

Isolated distal deep vein thromboses (IDDVT) are frequent; however, their optimal management is still controversial.

METHODS

We performed a retrospective study on inpatients undergoing ultrasound for suspected deep vein thrombosis (DVT) or with a particular risk profile, during 2016. This study aimed to assess the frequency of proximal deep vein thromboses (PDVT) and IDDVT; to evaluate therapeutic management and identify variables associated with early outcomes and mortality among IDDVT patients; to compare all-causes mortality between subjects with PDVT and IDDVT.

RESULTS

Among 21594 patients hospitalized in the study period 251 IDDVT and 149 PDVT were diagnosed; the frequency was 1.2% and 0.7% respectively. 19% of IDDVT patients died compared to 25.5% of PDVT subjects (OR=0.72; 95% CI=0.44-1.17; P=0.19). In IDDVT patients, age ≥80, cancer and intracranial bleeding increased the risk of death (OR=2; 95% CI=1.07-3.75, P=0.001; OR=8.47; 95% CI=3.28-21.88, P=0.0000003; OR=2.33; 95% CI=1.18-4.58, P=0.0003). A significant association between intracranial hemorrhage and both proximal extension by using the Fisher's exact test (P=0.031; OR=16.11; 95% CI=0.80-321.2), and composite of propagation to popliteal or to other calf veins (OR=8.28, 95% CI=2.07-33 P=0.001) was observed. Standard anticoagulation significantly reduced the composite of propagation to popliteal or to other calf veins (OR=0.07; 95% CI=0.009-0.61, P=0.007), and all-causes mortality (OR=0.37; 95% CI=0.17-0.8; P=0.02), without a significant increase of bleeding.

CONCLUSIONS

Among inpatients, IDDVT exceeded 60% of DVT. Mortality was not significantly different between IDDVT and PDVT subjects. Intracranial bleeding significantly increased the risk of propagation and death. Although standard anticoagulation decreased both these complications, further targeted studies are needed.

Management of antithrombotic therapy in gray areas of venous thromboembolism: a Delphi consensus panel

For some years now, direct-acting oral anticoagulants (DOACs) have entered the clinical practice for stroke prevention in non-valvular atrial fibrillation (NVAF) or for prevention and treatment of venous thromboembolism (VTE). However, there is uncertainty on DOACs' use in some clinical scenarios that are not fully explored by clinical trials, but commonly encountered in the real world. We report a Delphi Consensus on DOAC use in VTE patients. The consensus dealt with seven main topics: (1) clinical superiority of DOACs compared to VKAs; (2) therapeutic options for patients with intermediate risk PE; (3) therapeutic management of patients with deep vein thrombosis (DVT); (4) DOACs' role in oncological patients with VTE; (5) role of the reversal agent; (6) safety of low doses of DOACs in VTE patients; (7) DOACs long-term therapy (more than 12 months) in VTE patients; Forty-six physicians (cardiologists, internists, angiologists, oncologists, hematologists, and geriatricians) from Italy expressed their level of agreement on each statement by using a five-point Likert scale (1: strongly disagree, 2: disagree, 3: somewhat agree, 4: agree, 5: strongly agree). Votes 1-2 were considered as disagreement, while votes 3-5 as agreement. For each statement an agreement of ≥ 66% among the respondents was considered consensus. A brief discussion about the results for each topic is also reported.

Calf deep vein thrombosis – clinical relevance, diagnostic approaches and therapeutic options

Summary. Isolated distal deep vein thromboses (IDDVT) represent up to 50 % of legs deep vein thromboses (DVT). However, since their natural history is to date unknown, the need to diagnose and treat them is a matter of debate. The diagnostic strategy based on the assessment of pre-test probability and D-dimer demonstrated a scarse efficiency for IDDVT. The choice between a proximal and a complete ultrasonographic approach should be guided by the clinical context, the local expertise and the patient characteristics. Randomized and observational studies have analyzed the need of therapy and compared different regimens of anticoagulation, with conflicting results. Systematic reviews and meta-analyses tend to support the usefulness of an anticoagulant treatment, even if the optimal dose and duration are not still defined. A careful stratification of the patient’s profile, taking into account risk factors for proximal extension, recurrence and bleeding should address the therapeutic approach, which must always be discussed with an adequately informed patient. Further studies aimed to clarify the natural history of IDDVT, and to assess safety and efficacy of lower intensity and shorter duration protocols are urgently needed.

Anticoagulation in Deep Venous Thrombosis: Current Trends in the Era of Non- Vitamin K Antagonists Oral Anticoagulants

:

Anticoagulation therapy is the cornerstone of treatment in acute vein thrombosis (DVT) and it aims to reduce symptoms, thrombus extension, DVT recurrences, and mortality. The treatment for DVT depends on its anatomical extent, among other factors. Anticoagulation therapy for proximal DVT is clearly recommended (at least for 3 months), while AT for isolated distal DVT should be considered, especially in the presence of high thromboembolic risk factors. The optimal anticoagulant and duration of therapy are determined by the clinical assessment, taking into account the thromboembolic and bleeding risk in each patient in a case-by-case decision making. Non-Vitamin K antagonists oral anticoagulants (NOACs) were a revolution in the anticoagulation management of DVT. Nowadays, NOACs are considered as first-line therapy in the anticoagulation therapy for DVT and are recommended as the preferred anticoagulant agents by most scientific societies. NOACs offer a simple route of administration (oral agents), a rapid onset-offset of their action along with a good efficacy and safety profile in comparison with Vitamin K Antagonists (VKAs). However, there are issues about their efficacy and safety profile in specific populations with high thromboembolic and bleeding risks, such as renal failure patients, active-cancer patients, and pregnant women, in which VKAs and heparins were the standard care of treatment. Since the available data are promising for the use of NOACs in end-stage chronic kidney disease and cancer patients, several ongoing randomized trials are currently trying to solve that issues and give evidence about the safety and efficacy of NOACs in these populations.

Role of an age-adjusted D-dimer cutoff level in the diagnosis algorithm of lower limb deep venous thrombosis in outpatients

OBJECTIVE

Our goal was to analyze the utility of the age-adjusted D-dimer cutoff value in patients with clinically suspected deep venous thrombosis (DVT) in an ambulatory care setting, including distal DVTs.

METHODS

This was an observational cohort study of 606 outpatients older than 18 years presenting with low or moderate clinical suspicion of lower limb DVT (measured by Wells scale). D-dimer levels were obtained, and duplex ultrasound was performed (including femoropopliteal and below-knee veins). We calculated sensitivity, specificity, and positive and negative predictive D-dimer values and when to apply the age-adjusted D-dimer cutoff value (D-dimer threshold = age × 10 μg/L). We split patients older than 50 years into 10-year age groups. We constructed receiver operating characteristic curves of the D-dimer test for each group to find the best threshold (defined as the value of D-dimer that gives more specificity, maintaining the maximum possible sensitivity).

RESULTS

There were 249 men and 357 women with a mean age of 69.3 years; 41 patients were diagnosed with DVT. At a D-dimer threshold of 250 μg/L, sensitivity was 93%, specificity was 8%, positive predictive value was 7%, and negative predictive value was 94%. When the age-adjusted cutoff level was applied, global sensitivity was 76% and specificity 61%; positive predictive value was 12%, and negative predictive value was 97%. False-negative rate was 24%. We split patients older than 50 years into 10-year age groups: 50 to 60 years, 60 to 70 years, 70 to 80 years, and >80 years. The optimum thresholds were, respectively, 526 μg/L, 442.5 μg/L, 475 μg/L, and 549. μg/L.

CONCLUSIONS

In our series, the age-adjusted D-dimer cutoff level is not useful in the diagnostic algorithm of DVT.

Patient Management Strategies and Long-Term Outcomes in Isolated Distal Deep-Vein Thrombosis versus Proximal Deep-Vein Thrombosis: Findings from XALIA

Background  Overall, 30 to 50% of lower-limb deep-vein thrombosis (DVT) cases are isolated distal DVT (IDDVT). The recurrent venous thromboembolism (VTE) risk is unclear, leaving uncertainty over optimal IDDVT treatment. We present data on patients with IDDVT and proximal DVT (PDVT) from the prospective, noninterventional XALIA study of rivaroxaban for acute and extended VTE treatment.

Methods  Patients aged ≥18 years scheduled to receive ≥3 months' anticoagulation with rivaroxaban or standard anticoagulation were eligible, with follow-up for ≥12 months. We describe baseline characteristics, management strategies, and incidence proportions of VTE recurrence, major bleeding, and all-cause mortality in patients with IDDVT or PDVT, with or without distal vein involvement.

Findings  Overall, 1,004 patients with IDDVT and 3,098 with PDVT were enrolled; 641 (63.8%) and 1,683 (54.3%) received rivaroxaban, respectively. Patients with IDDVT were younger and had lower incidences of renal impairment, cancer, and unprovoked VTE than those with PDVT. On-treatment recurrence incidences for IDDVT versus PDVT were 1.0 versus 2.4% (adjusted hazard ratio [HR]: 0.56; 95% confidence interval [CI]: 0.29–1.08), and incidences posttreatment cessation were 1.1 versus 2.1% (adjusted HR: 0.65; 95% CI: 0.32–1.35), respectively. On-treatment major bleeding incidences were 0.9 versus 1.4% and mortality was 0.8 versus 2.2%, respectively. Median treatment duration in patients with IDDVT was shorter than in those with PDVT (102 vs. 192 days, respectively).

Interpretation  Patients with IDDVT had fewer comorbidities and were more frequently treated with rivaroxaban than those with PDVT. On-treatment and posttreatment recurrences were less frequent in patients with IDDVT.

Trial registration number:  NCT01619007.

Management of cancer-associated venous thromboembolism - a case-based practical approach

In patients with solid tumours or haematological malignancies, venous thromboembolism (VTE) is a leading cause of death and significantly contributes to morbidity and healthcare resource utilization. Current practice guidelines recommend long-term anticoagulation with low-molecular-weight heparin (LMWH) as the treatment of choice for cancer-associated VTE, based on clinical trial data showing an overall improved safety and efficacy profile of LMWH compared to vitamin K antagonists. However, several open questions remain, e. g. with regard to the intensity and duration of LMWH therapy; moreover, recent real-world evidence indicates that adherence to parenteral anticoagulation with LMWH over the course of treatment is poor in clinical practice. In this regard, the direct oral factor Xa or thrombin inhibitors (DOACs) have emerged as potential alternatives in the management of patients with cancer-associated VTE, albeit findings from randomized controlled studies with a direct head-to-head comparison of DOACs with LMWH, the current standard of care, are still lacking. Based on the case of a lymphoma patient experiencing symptomatic pulmonary embolism during immunochemotherapy, this article aims at both highlighting the current state-of-the-art approach to cancer-associated VTE and pointing out some of the unresolved, controversial issues clinicians have to face when taking care of haematology and oncology patients with already established or with high risk of developing VTE. These issues include the management of patients with incidental pulmonary embolism or thrombocytopenia, the use of DOACs, and the initiation of pharmacological thromboprophylaxis in non-surgical cancer patients.

Clinical course of isolated distal deep vein thrombosis in patients with active cancer: a multicenter cohort study

Essentials Isolated distal deep vein thrombosis (IDDVT) is frequently associated with cancer. No study has specifically evaluated the long-term clinical course of cancer-associated IDDVT. Patients with cancer-associated IDDVT are at very high risk of symptomatic recurrence and death. We observed low rates of major bleeding during anticoagulation.

SUMMARY

Background Although isolated distal deep vein thrombosis (IDDVT) is frequently associated with cancer, no study has specifically evaluated the long-term clinical course of IDDVT in this setting. Aim To provide data on the rate of recurrent venous thromboembolism (VTE), major bleeding events and death in IDDVT patients with active cancer. Patients and Methods Consecutive patients with active cancer and an objective IDDVT diagnosis (January 2011 to September 2014) were included from our files. We collected information on baseline characteristics, IDDVT location and extension, VTE risk factors, and type and duration of anticoagulant treatment. Results A total of 308 patients (mean age 66.2 [standard deviation (SD), 13.2 years]; 57.1% female) with symptomatic IDDVT and a solid (n = 261) or hematologic (n = 47) cancer were included at 13 centers. Cancer was metastatic in 148 (48.1%) patients. All but three (99.0%) patients received anticoagulant therapy, which consisted of low-molecular-weight heparin in 288 (93.5%) patients. Vitamin K antagonists were used for the long-term treatment in 46 (14.9%) patients, whereas all others continued the initial parenteral agent for a mean treatment duration of 4.2 months (SD, 4.6 months). During a total follow-up of 355.8 patient-years (mean, 13.9 months), there were 47 recurrent objectively diagnosed VTEs for an incidence rate of 13.2 events per 100 patient-years. During anticoagulant treatment, the annual incidence of major bleeding was 2.0 per 100 patient-years. Conclusions Cancer patients with IDDVT have a high risk of VTE recurrence. Additional studies are warranted to investigate the optimal intensity and duration of anticoagulant treatment for these patients.

Long-term recurrence of venous thromboembolism after short-term treatment of symptomatic isolated distal deep vein thrombosis: A cohort study

Isolated distal deep vein thrombosis (IDDVT) is a common clinical manifestation of venous thromboembolism (VTE). However, there are only scant and heterogeneous data available on the long-term risk of recurrent VTE after IDDVT, and the optimal therapeutic management remains uncertain. We carried out a retrospective cohort study of consecutive patients diagnosed with symptomatic IDDVT between 2004 and 2011, according to a predefined short-term treatment protocol (low molecular weight heparin (LMWH) for 4–6 weeks). The primary outcome was the occurrence of recurrent VTE. A total of 321 patients were enrolled. IDDVT was associated with a transient risk factor or cancer in 165 (51.4%) and 56 (17.4%) patients, respectively. LMWH was administered for 4–6 weeks to 280 patients (87.2%), who were included in the primary analysis. Overall, during a mean follow-up of 42.3 months, 42 patients (15%) developed recurrent VTE, which occurred as proximal DVT or PE in 21 cases. The recurrence rate of VTE per 100 patient-years was 3.5 in patients with transient risk factors, 7.2 in patients with unprovoked IDDVT, and 5.9 in patients with cancer ( p=0.018). At multivariable analysis, unprovoked IDDVT and previous VTE were significantly associated with recurrent VTE (HR 2.16, 95% CI 1.12–4.16 and HR 1.97, 95% CI 1.01–3.86, respectively). In conclusion, the long-term risk of recurrent VTE after IDDVT treated for 4–6 weeks is not negligible, in particular in patients with unprovoked IDDVT or cancer. Further studies are needed to clarify whether a longer, but definite treatment duration effectively prevents these recurrences.

A Predictive Score for Thrombosis Associated with Breast, Colorectal, Lung, or Ovarian Cancer: The Prospective COMPASS-Cancer-Associated Thrombosis Study

The COMPASS‐CAT study was undertaken in outpatients with breast, colon, lung, or ovarian cancer. The aim of the study was to identify the most relevat risk factors for symptomatic thromboembolism and to develop a risk assessment model applicable to patients after the initiation of anticancer treatment.

Background.

The stratification of outpatients on chemotherapy for breast, colorectal, lung, and ovarian cancers at risk of venous thromboembolism (VTE) remains an unmet clinical need. The derivation of a risk assessment model (RAM) for VTE in these patients was the aim of the study “Prospective Comparison of Methods for thromboembolic risk assessment with clinical Perceptions and AwareneSS in real life patients–Cancer Associated Thrombosis” (COMPASS–CAT).

Patients and Methods.

The derivation cohort consisted of 1,023 outpatients. Patients on low molecular weight heparin (LMWH) thromboprophylaxis were excluded. Documented symptomatic VTE was the endpoint of the study.

Results.

Patients had breast (61%), colorectal (17%), lung (13%), or ovarian cancer (8.6%) at localized (30%) or advanced stage (70%). In 64% of patients, cancer was diagnosed within the last 6 months prior to inclusion. Most of them were on chemotherapy when assessed. Symptomatic VTE occurred in 8.5% of patients. The COMPASS–CAT RAM includes the following variables: (a) anthracycline or anti‐hormonal therapy, (b) time since cancer diagnosis, (c) central venous catheter, (d) stage of cancer, (e) presence of cardiovascular risk factors, (f) recent hospitalization for acute medical illness, (g) personal history of VTE, and (h) platelet count. At 6 months, patients stratified at low/intermediate and high‐risk groups had VTE rates of 1.7% and 13.3%, respectively. The area under the curve of receiver operating characteristics analysis was 0.85. The sensitivity and specificity of the RAM were 88% and 52%, respectively. The negative and positive predictive values of the RAM were 98% and 13%, respectively.

Conclusion.

The COMPASS–CAT RAM includes reliable and easily collected VTE risk predictors and, in contrast to the Khorana score, it is applicable after the initiation of anticancer treatment in patients with common solid tumors. Its robustness for stratification of patients at high and low/intermediate VTE risk needs to be externally validated.

Implications for Practice.

The Prospective Comparison of Methods for thromboembolic risk assessment with clinical Perceptions and AwareneSS in real life patients–Cancer Associated Thrombosis (COMPASS–CAT) study provides a new risk assessment model (RAM) for venous thromboembolism (VTE) applicable in outpatients with breast, colorectal, lung or ovarian cancer. The COMPASS–CAT RAM is robust, applicable during chemotherapy and determines the need for VTE prévention by including reliable and easily collected VTE predictors associated with cancer status, its treatment as well as with patients' characteristics and comorbidities. An independent external validation of the RAM is indicated before its use in clinical practice.

Treatment of Isolated Below the Knee Deep Vein Thrombosis

The natural history of isolated distal deep-vein thrombosis (IDDVT) is still uncertain, as well as the real clinical risks associated with the disease and the need for its diagnosis and treatment. While more and more IDDVTs are diagnosed in everyday clinical practice, their appropriate therapeutic management is, unfortunately, far from straightforward, and different recommendations on how patients with diagnosed IDDVT should be treated are present between expert professionals and even among international guidelines. The present article aims at briefly reviewing the issue of IDDVT therapy in general, particularly focusing on the different approaches to the treatment of the disease that have been suggested by recent guidelines, those that are currently adopted in clinical practice, and necessary future directions.

Long-term outcomes of cancer-related isolated distal deep vein thrombosis: the OPTIMEV study

Essentials Clinical significance of cancer-related isolated distal deep vein thrombosis (iDDVT) is unknown. We studied patients with iDDVT, with and without cancer, and proximal DVT with cancer. Cancer-related iDDVT patients have a much poorer prognosis than iDDVT patients without cancer. Cancer-related iDDVT patients have a similar prognosis to cancer-related proximal DVT patients.

SUMMARY

Background Isolated distal deep vein thrombosis (iDDVT) (infra-popliteal DVT without pulmonary embolism [PE]) is a frequent event and, in the absence of cancer, is usually considered to be a minor form of venous thromboembolism (VTE). However, the clinical significance of cancer-related iDDVT is unknown. Methods Using data from the observational, prospective multicenter OPTIMEV cohort, we compared, at 3 years, the incidences of death, VTE recurrence and major bleeding in patients with cancer-related iDDVT with those in cancer patients with isolated proximal DVT (matched 1:1 on age and sex) and patients with iDDVT without cancer (matched 1:2 on age and sex). Results As compared with patients with cancer-related isolated proximal DVT (n = 92), those with cancer-related iDDVT (n = 92) had a similar risk of death (40.8% per patient-year (PY) vs. 38.3% per PY; aHR = 1.0, 95% CI[0.7-1.4]) and of major bleeding (3.8% per PY vs. 3.6% per PY, aCHR = 0.9 [0.3-3.2]) and a higher risk of VTE recurrence (5.4% per PY vs. 11.5% per PY; aCHR = 1.8 [0.7-4.5]). As compared with patients with iDDVT without cancer (n = 184), those with cancer-related iDDVT had a nine times higher risk of death (3.5% per PY vs. 38.3% per PY; aHR = 9.3 [5.5-15.9]), a higher risk of major bleeding (1.8% per PY vs. 3.6% per PY; aCHR = 2.0 [0.6-6.1]) and a higher risk of VTE recurrence (5.0% per PY vs. 11.5% per PY; aCHR = 2.0 [1.0-3.7]). The results remained similar in the subgroup of patients without history of VTE. Conclusion Patients with cancer-related iDDVT seem to have a prognosis that is similar to that of patients with cancer-related isolated proximal DVT and a dramatically poorer prognosis than patients with iDDVT without cancer. This underlines the high clinical significance of cancer-related iDDVT and the need for additional studies.

Incidence of pulmonary embolism in patients with isolated calf deep vein thrombosis

BACKGROUND

The severity of pulmonary embolism (PE) after isolated calf deep vein thrombosis (C-DVT) is controversial, which leads to inconsistent clinical decision making when treating C-DVT. This systematic review assessed PE frequency and severity in patients with C-DVT.

METHODS

Database searches were completed using MEDLINE and Scopus along with cross-referencing. Two independent reviewers used using rigorous inclusion and exclusion criteria to screen the papers. Data concerning PE and C-DVT characteristics as well as methods of detection were abstracted. Studies reporting combined outcomes for patients with proximal and C-DVT, those with concurrent PE at diagnosis, and retrospective studies not allowing the determination of C-DVT and PE as separate events were excluded.

RESULTS

Of 586 papers that were screened, 21 met inclusion criteria, which included eight randomized clinical trials and 13 prospective cohort studies. There was data heterogeneity among patients, methods of diagnosis, and follow-up. PE diagnosis was often based on ventilation/perfusion scanning, where more recent studies used computed tomography angiography. The PE is usually overestimated because it includes concurrent events. The incidence of PE from isolated C-DVT in our review was 0% to 6.2%. No fatal PEs were reported. No data were found on PE severity and patient outcomes regarding this complication.

CONCLUSIONS

Reported adverse outcomes of PE from C-DVT are infrequent, and clinical severity is unclear. Further studies are necessary to determine the actual risk associated with PE after C-DVT to establish proper treatment.

Management of distal deep vein thrombosis

Isolated distal deep vein thrombosis (DVT), also known as calf DVT, represents up to 50% of all lower limb DVT in ultrasound series and is therefore a frequent medical condition. Unlike proximal DVT and pulmonary embolism (PE), which have been extensively studied and for which management is well standardized, much less is known on the optimal management of isolated calf DVT. Recent data arising from registries and non-randomized studies suggest that most distal DVTs do not extend to the proximal veins and have an uneventful follow-up when left untreated. This data had some impact on the international recommendations which recently stated that ultrasound surveillance instead of systematic therapeutic anticoagulation might be an option for selected low-risk patients. However, robust data arising from randomized studies are scarce. Indeed, only five randomized trials assessing the need for anticoagulation for calf DVT have been published. Many of these trials had an open-label design and were affected by methodological limitations. The only randomized placebo-controlled trial included low-risk patients (outpatients without cancer or previous venous thromboembolic events (VTE)) and was hampered by a limited statistical power. Nevertheless, data from this trial tend to confirm that the use of therapeutic anticoagulation in low-risk patients with symptomatic calf DVT is not superior to placebo in reducing VTE, but is associated with a significantly higher risk of bleeding. Further randomized studies are needed to define the best therapy for high-risk patients (inpatients, patients with active cancer or previous VTE), and the optimal dose and duration of treatment.

Controversies in venous thromboembolism: the unique case of isolated distal deep vein thrombosis

Venous thromboembolism (VTE) represents the third leading cause of cardiovascular mortality, and it is the main cause of preventable mortality in hospitalized patients. Among VTE, there is the unique case of isolated distal deep vein thrombosis (IDDVT), which still lacks an agreement in terms of optimal therapeutic strategy. Although most IDDVTs are self-limiting and associated with a very low risk of embolic complications, still not all IDDVTs can be safely identified as stable. Lack of strong scientific evidence, fear of thromboembolic complications, and risk of bleeding upon initiation of anticoagulant treatment result in very heterogeneous therapeutic strategies among physicians. Here, we provide a comprehensive review of the literature, highlight the many controversial issues regarding IDDVTs, and call for a consensus of experts aimed to shed new light on the gray areas of IDDVT management and therapy.

Systematic review of the complications following isolated calf deep vein thrombosis

Background

A large number of studies have examined the potential complications of calf deep vein thrombosis (DVT). There is no consensus on when or how to treat patients to prevent these complications. This systematic review assessed the rate of proximal propagation, pulmonary embolism, major bleeding and recurrence in patients with isolated calf DVT.

Methods

Database searches of MEDLINE, the Cochrane Library, Scopus, CINAHL and Web of Science were undertaken along with extensive cross-referencing. Two independent reviewers screened the papers using stringent inclusion and exclusion criteria. Included studies were graded on six methodological standards. Data on propagation, pulmonary embolism, recurrence and major bleeding were abstracted.

Results

A total of 4261 papers were found; 15 met the inclusion criteria, including five randomized clinical trials and ten prospective cohort studies. The propagation rate to the popliteal vein or above was around 9 per cent and the rate of pulmonary embolism was close to 1·5 per cent. No studies found anticoagulant therapy to reduce the rate of adverse outcomes.

Conclusion

The literature on calf DVT is heterogeneous, limiting conclusions from data analysis. Adverse outcomes are infrequent and studies do not suggest that they are reduced by anticoagulation.

Kallmann syndrome patient with gender dysphoria, multiple sclerosis, and thrombophilia

One of the challenging issues in patients with complex problems is that the various diseases and their treatment can influence each other and present unusual hurdles in management. We investigated one such complex case. A 34-year-old XY male presented with azoospermia, detected on semen analysis for pre-orchidectomy sperm banking. He had a 20-year history of gender dysphoria and bilateral breast swelling. The patient suffered a deep vein thrombosis at the age of 19 years. Examination confirmed clinical features of Kallmann syndrome including unilateral cryptorchidism, micropenis, congenital anosmia, and bimanual synkinesis (mirror movements), with reduced serum testosterone and normal gonadotropin levels demonstrating hypogonadotropic hypogonadism. MRI showed missing olfactory bulbs. Osteopenia and reduced vitamin D levels of 21 nmol/L were identified. He was found to harbor a heterozygous factor-V-Leiden mutation. The genetic basis of Kallmann syndrome remains unknown: his screening tests were negative for mutations in CHD7, FGF8, FGFR1, GNRH1, GNRHR, HS6ST1, KAL1, KISS1R, KISS1, NELF, PROK2, PROKR2, TAC3, and TACR3. The patient initially declined testosterone therapy with a view to undergo gender reassignment. Over the next 2 years, the patient experienced recurrent episodes of weakness and paresthesia, associated with classical MRI appearances of multiple sclerosis-related demyelination in the spinal cord and brain. Although it was difficult to elucidate an association between the patient's gender dysphoria and untreated congenital hypogonadism, his desire to become female together with his co-existing thrombophilia, presented challenges to the administration of hormone treatment. Furthermore, we have considered an association between multiple sclerosis and hypogonadotropic hypogonadism.

Management of isolated calf vein thrombosis in cancer patients

The treatment of isolated calf vein thrombosis remains widely debated. This study highlights the characteristics of isolated calf vein thrombosis in cancer patients and compares to isolated calf vein thrombosis in patients without history of cancer. Between July 2013 and April 2014, a retrospective chart review of consecutive patients with isolated calf vein thrombosis was performed recording patient risk factors, ultrasound characteristics of the thrombus, treatment modalities, long-term recurrence of venous-thromboembolism, incidence of bleeding, and mortality. Of 131 patients with isolated calf vein thrombosis, 53 (40.1%) had history of cancer. Isolated calf vein thrombosis occurred at an older age in cancer patients (66.7 vs 58.5 years, p = 0.004). The anatomical characteristics of isolated calf vein thrombosis on ultrasound were comparable in both groups. Isolated calf vein thrombosis in cancer patients was less likely to be treated with anticoagulation (60.4% vs 80.8%, p = 0.018). However, a trend towards higher incidence of bleeding after initiation of anticoagulation for isolated calf vein thrombosis in cancer patients (11.3% vs 6.4%, p = 0.351) was noted. Mortality in cancer patients was higher (37.7% vs 9.00%, p < 0.001) but was unrelated to isolated calf vein thrombosis or its treatment. In conclusion, the risks of bleeding seem to exceed the benefits of anticoagulation in approximately 50% of cancer patients with isolated calf vein thrombosis. The management of isolated calf vein thrombosis does not seem to impact the survival of cancer patients.

Fatal pulmonary embolization after negative serial ultrasounds

BACKGROUND

Isolated distal deep vein thrombosis (DVT) is not traditionally viewed as a potentially life-threatening condition. There are conflicting recommendations regarding its evaluation and treatment, and wide variability in clinical practice. The presentation of this case highlights the fatal potential of this condition.

CASE REPORT

This is the report of a previously healthy young woman who presented to the emergency department with calf pain concerning for a DVT. She received two radiologist-performed duplex ultrasound examinations of the affected extremity, both of which were negative, but suffered a sudden cardiac arrest several hours after the second study. Autopsy attributed the death to DVT and pulmonary embolism. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: This case highlights the risk for fatal pulmonary embolization, even after normal serial ultrasound examinations to exclude DVT.