Residual Vein Thrombosis Echogenicity Is Associated to the Risk of DVT Recurrence: A Cohort Study.

Although deep vein thrombosis (DVT) recurrence is a common late complication of the disease, there are few predictive markers to risk-stratify patients long-term after the thrombotic event. The accuracy of residual vein thrombosis (RVT) in this context is controversial, possibly due to a lack of a standardized methodology. The objective of the study was to evaluate the accuracy of RVT echogenicity as a predictive marker of late DVT recurrence. To evaluate the accuracy of RVT echogenicity as a predictive marker of late DVT recurrence. This prospective study included patients with history of DVT in the past 33 months. Ultrasound examination was performed to detect the presence of RVT, and its echogenicity was determined by calculating the grayscale median (GSM) of the images. Blood samplings were taken for plasma D-dimer levels. Patients were followed-up for 28 months and the primary end point was DVT recurrence. Deep vein thrombosis recurrence was confirmed or excluded by ultrasound during the follow-up. Fifty-six patients were included, of which 10 presented DVT recurrence during the follow-up. D-dimer levels above 630 ng/mL conferred higher risk for recurrence with a negative predictive value of 94%. The absence of RVT was a protective marker for recurrence with a negative predictive value of 100%. Also, the presence of hypoechoic RVT, determined by GSM values below 24, positively predicted 75% of DVT recurrences. Our results suggest that the persistence of RVT and, particularly, the presence of hypoechoic thrombi (GSM < 24) are predictive markers of the risk of DVT recurrence. Residual vein thrombosis echogenicity, by GSM analysis, could represent a new strategy for the evaluation of recurrence risk in patients with DVT.

Severe postthrombotic syndrome is associated with characteristic sonographic pattern of the residual thrombosis.

Postthrombotic syndrome (PTS) may affect 50% of patients with deep venous thrombosis, 5-10% of them may present severe manifestations. The causes for PTS development and severity have not been well established. This study evaluated whether PTS may be associated with the presence, and echogenicity, of the residual vein thrombosis (RVT). We included patients with a history of deep venous thrombosis in the past 58 months. These patients were further evaluated for PTS diagnosis, clinical comorbidities, plasma levels of D-dimer, serum levels of C-reactive protein and for the presence of RVT. Particularly, RVT was detected by ultrasound examination and the residual thrombi echogenicity was determined by grayscale median (GSM). Fifty-six patients were included, of which 41 presented PTS. Mild PTS was detected in 23 patients, moderate PTS in 11 and severe PTS in seven patients. Patients with severe PTS showed higher body mass index, higher abdominal circumference and higher C-reactive protein levels when compared with the other patients (P = 0.007, P = 0.002, P = 0.02, respectively). The ultrasound-generated GSM was significantly lower in patients with severe PTS compared with patients with mild-moderate PTS or no PTS (median = 24, 35 and 41, respectively; P = 0.04). A GSM value less than 25, which was consistent with a hypoechoic RVT, was the best cut-off value to discriminate patients with severe PTS from those with mild or moderate PTS and those without PTS. RVT is a common finding among patients with PTS and the echogenicity of the RVT may impact the severity of PTS.

Performance of a point-of-care device in determining prothrombin time in an anticoagulation clinic.

New portable devices for the measurement of the prothrombin time and the international normalized ratio (INR) from capillary blood samples have demonstrated to have good correlation with classic laboratory methods in multiple clinical settings. In this study, we evaluated the performance of the point-of-care device CoaguChek XS (CoaguChek XS; Roche Diagnostics, Basel, Switzerland), comparing the INR results with the standard laboratory method (automatic coagulometer) in an outpatient anticoagulation clinic. Results were compared by linear regression and Bland-Altman plot. Two hundred paired results were collected from 170 patients in a period of 90 days. The main indications for anticoagulation were prophylaxis of venous thromboembolic events, atrial fibrillation and prosthetic heart valves. Mean INR results obtained with the portable device and with the standard laboratory method were 2.22 ±â€Š0.70 and 2.30 ±â€Š0.77, respectively. The proportion of patients with supratherapeutic INRs was 13.5%. The CoaguChek XS monitor tended to underestimate the INR on average by 0.08 U. The correlation coefficient (R) between the two methods was 0.91 (P < 0.0001). The CoaguChek XS device is suitable for INR monitoring in patients in outpatient oral anticoagulation clinics.

Diagnosis of Scott syndrome in patient with bleeding disorder of unknown cause.

Scott syndrome is a rare bleeding disorder due to an impaired exposure of phosphatidilserine on the platelet membrane, compromising the platelet procoagulant activity, thrombin generation and, thus, the clot formation. We report a case of a 17-year-old female adolescent with bleeding episodes of unknown cause. She had normal coagulation, but altered platelet aggregation under arteriolar flow, indicating platelet dysfunction. Furthermore, the expression of Annexin V was markedly reduced and the diagnosis of Scott syndrome was established. She was treated with platelet transfusions and demonstrated a clinical improvement. Scott syndrome may be investigated in cases with bleeding history and normal coagulation tests.

Polymorphisms and mutations in vWF and ADAMTS13 genes and their correlation with plasma levels of FVIII and vWF in patients with deep venous thrombosis.

BACKGROUND: Increased levels of factor VIII (FVIII) are a prevalent and independent risk factor for deep venous thrombosis (DVT) and are affected by von Willebrand factor (vWF) levels. DESIGN AND METHODS: ADAMTS13 contributes to vWF levels, and we investigated genetic polymorphisms previously described to be associated with decreased levels of these proteins in 435 patients with DVT (126 M and 309 F; median age 37 years, range 18-68 years) and 580 controls (163 M and 417 F; median age 35 years, range 18-68 years). Subsequently, we investigated the relationship between the genotypes and plasma levels of FVIII, vWF, and DVT risk. RESULTS: Patients with DVT showed higher plasma levels of FVIII:C, FVIII:Ag, and vWF:Ag (P < .001) when compared to controls. Patients and controls heterozygous for the 4751A>G polymorphism in the vWF gene presented decreased levels of vWF:Ag, FVIII:Ag, and FVIII:C (P < .001), but this was not a protective factor for DVT. Individuals heterozygous for 1852C>G polymorphism in ADAMTS13 gene, which is associated with reduced levels of ADAMTS13, had significantly elevated levels of vWF:Ag (P = .001), FVIII:Ag (P = .01), and FVIII:C (P = .02). However, this polymorphism was not a risk factor for DVT in our study. Heterozygosis for a new polymorphism identified in ADAMTS13 gene, 1787-26G>A, was significantly associated with elevated levels of FVIII:C (P = .02) when compared to wild type. CONCLUSIONS: Despite the tempting assumption that genetic factors that change ADAMTS13 activity might modulate the risk of DVT by altering vWF and FVIII levels, the polymorphisms analyzed in this study did not correlate with DVT risk among patients investigated.

Long-term prospective study of recurrent venous thromboembolism in a Hispanic population.

The aim of this study was to assess the incidence and risk factors for recurrent venous thromboembolism (VTE) in a Hispanic population. We prospectively followed 343 patients after a first episode of objectively proven VTE. We excluded all patients with VTE at unusual sites, older than 70 years old, with neoplasia, liver or renal chronic disease and antiphospholipid syndrome. Predictors for recurrence were evaluated by Cox model. The probability of recurrent VTE was estimated by the method of Kaplan-Meier. The cumulative probability of recurrent VTE was 19.1% in 5 years and 30.0% in 10 years. Male sex [relative risk (RR) 1.7, 95% confidence interval (CI) 1.0-2.8], spontaneous first VTE (RR 2.9, 95% CI 1.7-5.0) and FII G20210A mutation (RR 4.2, 95% CI 1.9-9.4) were independent risk factors for recurrent VTE. The fibrinogen, coagulation factors VIII, IX, X and XI were measured in 200 patients and were not associated to thrombotic recurrence risk. This study indicates that the incidence of recurrent VTE is high in Hispanics and depends on clinical and laboratory findings. In this population, FII G20210A mutation may represent a specific risk factor for recurrence. The inclusion of different ethnic populations in epidemiological studies of VTE as well as new approaches to the management of anticoagulation therapy in Hispanics is warranted.