PO-40 - Real-life use of non-vitamin k antagonist oral anticoagulants in patients with cancer associated venous thromboembolism: data from a prospective cohort.

INTRODUCTION: Cancer associated thrombosis (CAT) has an increased risk of recurrent venous thromboembolism (VTE). Type, stage of cancer and chemotherapy (CHT) influence thromboembolic risk. The use of novel oral anticoagulants (NOACs) is controversial in patients with CAT. AIM: The aim of this study is to assess mortality, recurrent VTE and bleeding complications in patients with CAT and in patients without cancer receiving NOACs. MATERIALS AND METHODS: Consecutive patients with acute objectively confirmed VTE receiving NOACs within 1 month from diagnosis are included from September 2013 in an ongoing prospective cohort study. Characteristics of patients and outcome are reported according to the presence of CAT. Chi-squared test and Student' t-test are used. RESULTS: As for November 10(th) 2015, 472 patients were included in the study: 78 with CAT (16.5%). Lung, breast, gastrointestinal and genitourinary cancer was observed in 16%, 24%, 20% and 24% of patients with CAT, respectively. 31 patients with CAT (40%) were on CHT or radiotherapy (RT). 10 patients with CAT (13%) had at least an additional risk factor for VTE (4 had a CVC related thrombosis) and 34 (43.5%) were inpatients. Baseline characteristics of patients with and without CAT are reported in the Table. Pulmonary embolism was index VTE in 152 patients: 24.4% of patients with CAT and in 33.8% of those without cancer (p=0.10). DVT only was present in 320 patients and 78 had both DVT and PE. Among NOACs patients, 312 (66%) received initial loading dose: 61% of those with CAT and 67% without. 53 (11%) received reduced maintenance doses (10% with CAT, 11% without). As for nowadays, 272 patients had at least 3 months of follow-up, the mean follow-up being 8.6 months. 20 patients died (7.3%): 17 were cancer related deaths. Non cancer related death occurred in 1 patient with CAT (2%) and in 2 patients without (0.9%). No fatal bleedings or fatal VTE recurrences occurred. Patients recruitment and follow-up is currently ongoing aimed at assessing mortality, recurrent VTE and bleeding complications. Updated results on clinical outcomes will be presented at the congress. CONCLUSIONS: Patients with CAT receiving NOACs are treated as patients without CAT in terms of use of loading doses and maintenance treatment. Upper arm thrombosis is more frequently involved in CAT patients and proximal lower vein in patients without CAT. Non cancer related mortality was higher in CAT patients but no fatal recurrences or fatal bleedings were observed so far.

[Bilateral aneurysm of the common iliac vein: a case report]. / Aneurisma bilaterale della vena iliaca commune: descrizione di un caso clinico.

Vein aneurysm is a rare encountered lesion. We describe a case of extensive bilateral iliac vein aneurysm as an accidental finding during abdominal ultrasonography of a 39-year-old male marathon runner. Common iliac vein dimensions were respectively: right 39 x 42 x 60 mm and left 43 x 55 x 73 mm, with no signs of thrombosis or spontaneous echocontrast; mean flow velocity was 0.10 m/s with normal dynamics of venous flow. Furthermore we observed abnormal dilatation of the cava vein as well as the common femoral and popliteal veins. Other venous districts, detectable by color-Doppler ultrasound were normal. Known congenital or acquired conditions predisposing to aneurysm and/or ectasia were not detected.

Distribution and occlusiveness of thrombi in patients with surveillance detected deep vein thrombosis after hip surgery.

Venous thromboembolism is a leading cause of in-hospital postoperative morbidity and mortality. Postoperative deep vein thrombosis (DVT) is usually asymptomatic. A number of studies have consistently shown that the non invasive diagnostic methods are inaccurate in the screening of asymptomatic DVT. Failure of non invasive diagnostic methods to detect thrombi in asymptomatic patients has been suggested to be due to the features of thrombi in these patients. The aim of this study was to assess the distribution and the occlusiveness of thrombi in a series of 321 asymptomatic hip surgery patients with adequate bilateral venography of the lower limbs. Venography was performed 10 +/- 1 days after hip surgery. DVT was found in 180 limbs (28.0%). The distribution of thrombi was as follows: 26 (14.4%) isolated proximal thrombi, 55 (30.6%) proximal and distal thrombi, 99 (55.0%) isolated calf thrombi. We found that 14 of the 81 proximal trombi (17.3%) involved the superficial femoral vein either as exclusive location or in association with calf veins. An involvement of common femoral, superficial femoral and popliteal vein was observed in 37 (45.7%), 39 (48.1%) and 44 (54.3%) cases of the 91 proximal DVT. These thrombi were non occlusive in 25 (67.6%), 22 (56.4%) and 26 (59.1%) limbs, respectively. An involvement of at least one peroneal, anterior tibial and posterior tibial veins was observed in 118, 13 and 89 cases of the 220 distal thrombi. These thrombi were non occlusive in 61 (51.7%), 10 (76.9%) and 30 (33.7%) of the cases. We conclude that the majority of thrombi found in asymptomatic hip surgery patients are non occlusive. In view of this, non invasive diagnostic methods based upon venous flow measurement will be unlikely to improve the diagnosis of asymptomatic DVT. The high incidence of isolated superficial femoral vein thrombosis necessitates that real-time B-mode ultrasonography should be performed examining the entire proximal venous system.

Diagnosis of deep vein thrombosis in asymptomatic high-risk patients.

Postoperative deep vein thrombosis is usually asymptomatic so that pulmonary embolism is often the first clinical manifestation of venous thromboembolism. The diagnostic accuracy of impedance plethysmography, 125I-fibrinogen leg scanning and real-time B-mode ultrasonography has been extensively evaluated in patients with asymptomatic deep vein thrombosis. Impedance plethysmography has been evaluated in a number of studies and its sensitivity has been invariably found to be approximately 20% or less. These results seem to be due to the high prevalence in asymptomatic patients of distal, small and nonocclusive thrombi, unable to produce a critical obstruction of the venous flow. The accuracy of 125I-fibrinogen leg scanning has been assessed in a number of studies and found to be significantly different in the initial and more recent studies. This difference has been found to be due to the quality of the study design: the better the methodology, the lower the diagnostic accuracy of 125I-fibrinogen leg scanning. The association of impedance plethysmography and 125I-fibrinogen leg scanning do not result in an improvement of the results obtained by the single diagnostic method. Study methodology strongly influenced the results obtained with real-time B-mode ultrasonography with a reported sensitivity of approximately 50% in the studies performed adopting an appropriate methodology. In conclusion, noninvasive diagnostic methods are inaccurate in the diagnosis of asymptomatic deep vein thrombosis. Thus, venography remains the only accurate diagnostic method for the diagnosis of asymptomatic deep vein thrombosis.

Features of thrombi and diagnostic accuracy of impedance plethysmography in symptomatic and asymptomatic deep vein thrombosis.

Impedance plethysmography (IPG) has high sensitivity and specificity in patients with symptomatic deep vein thrombosis (DVT) while it fails to detect asymptomatic DVT. The aim of this study was to determine whether the features of thrombi such as location, size and occlusiveness could explain the different accuracy of IPG in symptomatic and asymptomatic DVT patients. One-hundred and seventeen consecutive outpatients with a clinical suspicion of DVT and 246 consecutive patients undergoing hip surgery were admitted to the study. In symptomatic patients IPG was performed on the day of referral, followed by venography, while in asymptomatic patients IPG was performed as a surveillance programme, followed by bilateral venography. A venography proved DVT was observed in 37% of the symptomatic patients and 34% of the asymptomatic limbs. A significantly higher proportion of proximal DVTs was found in symptomatic patients than in asymptomatic patients (78% vs 46%; p = 0.001). The mean Marder score, taken as an index of thrombus size, was significantly higher in symptomatic patients than in asymptomatic patients (19.0 vs 9.6; p = 0.0001). A significantly higher proportion of occlusive DVTs was observed in symptomatic than in asymptomatic patients (69% vs 36%; p = 0.001). We conclude that the unsatisfactory diagnostic accuracy of IPG in asymptomatic DVT is due to the high prevalence of distal, small and non occlusive thrombi. Such thrombi are unlikely to cause a critical obstruction of the venous outflow and therefore to produce a positive IPG.

Detection of asymptomatic deep vein thrombosis by real-time B-mode ultrasonography in hip surgery patients.

The aim of this study was to prospectively evaluate the accuracy of real-time B-mode ultrasonography in the diagnosis of asymptomatic proximal deep vein thrombosis (DVT) in hip surgery patients. Venography was adopted as the gold standard. We studied 100 consecutive patients undergoing hip surgery: 60 patients for hip fracture and 40 patients for elective hip replacement. Bilateral real-time B-mode ultrasonography was performed prior to bilateral venography. The two diagnostic procedures were performed on the same day by different investigators unaware of the assigned prophylatic regimen for DVT. Compressibility of the vein segment was adopted as the single criterion for DVT. Venography was performed and judged by radiologists unaware of the ultrasonography results. In 13 limbs venography was either impossible to perform or not adequate for judgement. Ultrasonography and an adequate venography was obtained in 187 limbs. A venography proven DVT was observed in 49 limbs (26.2%) and a proximal DVT in 21 limbs (11.2%). All the patients were asymptomatic for DVT. The sensitivity and specificity of real time B-mode ultrasonography for proximal DVT were 57% (95% confidence interval: C.I. 36-80) and 99% (C.I. 99-100), respectively and the positive and negative predictive values were 93% (C.I. 73-100) and 95% (C.I. 91-97), respectively. The sensitivity and specificity for overall DVT were 25% (C.I. 11-38) and 99% (C.I. 97-100), respectively and the positive and negative predictive values were 92% (C.I. 73-100) and 79% (C.I. 76-85), respectively. Our data indicate that real-time B-mode ultrasonography for its high specificity could make venography unnecessary in patients with positive results.(ABSTRACT TRUNCATED AT 250 WORDS)

The influence of venous occlusion on the status of protein S.

In the present study the effect of perturbation of the vessel wall by venous occlusion on protein S release, was evaluated in 10 healthy male volunteers. A 9% (P less than 0.01) increase in free protein S and a 7% (NS) in total protein S over the baseline were observed 7 min after venous occlusion, whereas von Willebrand factor antigen (vWF:Ag)--a known release product of vascular endothelium--increased by 11% (P less than 0.01). In addition, the possibility of free protein S release from unstimulated platelets was investigated in pre- and post-occlusion samples incubated at room temperature for 24 h as whole blood or platelet-rich plasma. An increase in the mean free protein S was observed in the pre-occlusion samples which peaked after 4 h of incubation--121% at time 0 to 130% (P less than 0.05) of the normal pooled plasma whereas total protein S increased by only 4% (NS). In the post-occlusion samples, a similar peak in mean free protein S levels was observed after 12 h of incubation--132% at time 0 increased to 142% (P less than 0.01) of the normal human plasma pooled and the total protein S was increased by 8.55 (P less than 0.05). Small but significant increases in vWF:Ag levels were observed at 2 h and 6 h for the pre- and post-occlusion samples, respectively. No changes in C4b-binding protein were observed throughout the study. We conclude that, firstly, venous occlusion causes release of protein S in addition to vWF:Ag and, secondly, unstimulated platelets release protein S in addition to vWF:Ag.