Early thrombosis after iliac stenting for venous outflow occlusion is related to disease severity and type of anticoagulation.

BACKGROUND: Stenting of the iliac venous system is often performed for symptomatic obstruction, with high patency rates reported. However, patients with post-thrombotic disease and those with more extensive obstruction have experienced poorer outcomes, including a higher rate of early post-stent thrombosis. In the present study, we examined the outcomes of patients with complete venous outflow occlusion. We focused on the variables associated with early post-stenting thrombosis to identify opportunities to reduce its incidence. METHODS: From 2010 to 2020, the patients who had undergone stenting for chronic obstruction of the common femoral vein, iliac veins, and/or inferior vena cava were retrospectively reviewed. The pre- and intraoperative imaging studies were examined to identify those who had had total occlusion of one venous outflow segment (type III disease) or multiple venous outflow segments (type IV disease). The patient characteristics and procedural and post-stent variables were recorded. The post-procedure follow-up visits and imaging studies were reviewed to determine stent patency and thrombotic complications. Key variables were studied to determine their association with early stent reocclusion. RESULTS: A total of 106 patients were identified, including 43 with type III (40.6%) and 63 with type IV (59.4%) disease. The mean patient age was 49.8 ± 13.7 years, and the mean stented length was 177.3 ± 63 mm. Stainless steel Wallstents were used solely in 44% of the cases, with a variety of nitinol stents used in the remainder. Femoral vein inflow was minimally diseased in 50% of the cases, moderately diseased in 26%, and severely diseased or occluded in 24%. Antiplatelet medications were prescribed after intervention for 52.8% and anticoagulation medication for 95.3% of the patients. Occlusion of the stented segment occurred within 3 months in 25.5%. Primary patency was 74.5% at 3 months, 63.9% at 12 months, and 58.5% at 3 years. Secondary patency was 93.4% at 3 months and 76.1% at 3 and 5 years. Univariate analysis of variables related to early stent thrombosis identified the presence of a hypercoagulable state, type IV obstruction, and the type of anticoagulation used after stenting were associated with early stent thrombosis. On multivariate analysis, each of these variables was independently associated with early stent thrombosis. The presence of type IV obstruction (odds ratio [OR], 4.596; 95% confidence interval [CI], 1.424-18.109) or a hypercoagulable state (OR, 3.835; 95% CI, 1.207-12.871) was associated with significantly greater odds of reocclusion than was class III obstruction and no hypercoagulable state. Treatment with low-molecular-weight heparin for >10 days was associated with significantly lower odds (OR, 0.012; 95% CI, 0.001-0.130) of reocclusion. CONCLUSIONS: Patients who require recanalization of a completely occluded venous outflow tract before stenting have a high rate of early reocclusion. Patients with more extensive occlusion and a hypercoagulable state have greater odds of reocclusion. Treatment with low-molecular-weight heparin for >10 days reduced the odds of early reocclusion.

What works, why and how? A scoping review and logic model of rural clinical placements for allied health students.

BACKGROUND: Allied health services are core to the improvement in health outcomes for remote and rural residents. Substantial infrastructure has been put into place to facilitate rural work-ready allied health practitioners, yet it is difficult to understand or measure how successful this is and how it is facilitated. METHODS: A scoping review and thematic synthesis of the literature using program logic was undertaken to identify and describe the contexts, mechanisms and outcomes of successful models of rural clinical placements for allied health students. This involved all empirical literature examining models of regional, rural and remote clinical placements for allied health students between 1995 and 2019. RESULTS: A total of 292 articles were identified; however, after removal of duplicates and article screening, 18 were included in the final synthesis. Australian papers dominated the evidence base (n = 11). Drivers for rural allied health clinical placements include: attracting allied health students to the rural workforce; increasing the number of allied health clinical placements available; exposing students to and providing skills in rural and interprofessional practice; and improving access to allied health services in rural areas. Depending on the placement model, a number of key mechanisms were identified that facilitated realisation of these drivers and therefore the success of the model. These included: support for students; engagement, consultation and partnership with key stakeholders and organisations; and regional coordination, infrastructure and support. Placement success was measured in terms of student, rural, community and/or program outcomes. Although the strength and quality of the evidence was found to be low, there is a trend for placements to be more successful when the driver for the placement is specifically reflected in the structure of the placement model and outcomes measured. This was seen most effectively in placement models that were driven by the need to meet rural community needs and upskill students in interprofessional rural practice. CONCLUSION: This study identifies the factors that can be manipulated to ensure more successful models of allied health rural clinical placements and provides an evidence based framework for improved planning and evaluation.

Decreased hepatocellular carcinoma tumor burden with the achievement of hepatitis C virus sustained virologic response: unlocking the potential of T-cell-mediated immunosurveillance.

We describe two cases of patients with hepatitis C virus (HCV) treated with direct-acting antiviral (DAA) therapy who had dramatic improvement in hepatocellular carcinoma (HCC) tumor burden with DAA therapy alone. Both patients were diagnosed with HCC on screening magnetic resonance imaging shortly after beginning DAA therapy. Both patients achieved sustained virologic response (SVR) with dramatic improvement in HCC tumor burden on follow-up imaging without HCC treatment. Patients with multifocal or advanced HCC are infrequently treated with antiviral therapy for HCV. As a result, these cases provide unique insight into the ongoing debate regarding the impact of SVR on existing and recurrent HCC. We review the current literature regarding this debate, as well as the theory of immunosurveillance. We postulate that DAA therapy activates CD8+ T cells to induce a T-cell-mediated response and increased immunosurveillance to virus-induced liver cancer.

Pacific acuity test: testability, validity, and interobserver reliability.

PURPOSE: The Pacific Acuity Test (PAT) is a new vanishing optotype test designed to measure recognition visual acuities in preverbal children using a face and opposing oval figure in a forced-choice preferential looking format. This study evaluates the testability, validity, and interobserver reliability of the PAT. METHODS: Fifty-two subjects, aged 6 to 36 months, were tested by a primary observer to determine both recognition and resolution visual acuities using the PAT. Subjects were also tested using the Cardiff Acuity Test (CAT) to provide comparative resolution acuities. Two additional observers independently evaluated video-recorded subject responses for testability and interobserver reliability analysis. An independent grader determined acuity thresholds from each observer's observations, and a logistic regression model was used for additional analysis of acuity thresholds, validity, and testability. RESULTS: Forty-seven of 52 subjects completed testing to obtain visual acuities with the PAT. Sixty-nine percent of subjects followed the desired forced-choice strategy to yield recognition acuities with the PAT. Testability for children younger than 18 months was 44%, whereas 96% of children 18 months and older responded to the recognition testing format. Testability for resolution acuity was 92% and 98% for the PAT and CAT, respectively. The mean difference between PAT recognition and CAT resolution acuity thresholds (PAT-CAT) was +0.11 logMAR (0.15 SD, p < 0.001). The observers were in agreement as determined by intraclass correlation coefficients of 0.90 for both PAT recognition and the CAT. CONCLUSIONS: High testability and valid recognition acuity measures were achieved using the PAT with children by approximately 18 months of age. The recognition acuities obtained with the PAT were higher, particularly for younger subjects, than comparative resolution acuities found with both the PAT and CAT. Interobserver reliability of observers was the same between the PAT and the CAT.