Background Patients hospitalised with COVID-19 are at risk for thrombotic events after discharge; the role of extended thromboprophylaxis in this population is unknown. Methods In this open-label, multicentre, randomised trial conducted at 14 centres in Brazil, patients hospitalised with COVID-19 at increased risk for venous thromboembolism (International Medical Prevention Registry on Venous Thromboembolism [IMPROVE] venous thromboembolism [VTE] score of ≥4 or 2–3 with a D-dimer >500 ng/mL) were randomly assigned (1:1) to receive, at hospital discharge, rivaroxaban 10 mg/day or no anticoagulation for 35 days. The primary efficacy outcome in an intention-to-treat analysis was a composite of symptomatic or fatal venous thromboembolism, asymptomatic venous thromboembolism on bilateral lower-limb venous ultrasound and CT pulmonary angiogram, symptomatic arterial thromboembolism, and cardiovascular death at day 35. Adjudication was blinded. The primary safety outcome was major bleeding. The primary and safety analyses were carried out in the intention-to-treat population. This trial is registered at ClinicalTrials.gov , NCT04662684 . Findings From Oct 8, 2020, to June 29, 2021, 997 patients were screened. Of these patients, 677 did not meet eligibility criteria; the remaining 320 patients were enrolled and randomly assigned to receive rivaroxaban (n=160 [50%]) or no anticoagulation (n=160 [50%]). All patients received thromboprophylaxis with standard doses of heparin during hospitalisation. 165 (52%) patients were in the intensive care unit while hospitalised. 197 (62%) patients had an IMPROVE score of 2–3 and elevated D-dimer levels and 121 (38%) had a score of 4 or more. Two patients (one in each group) were lost to follow-up due to withdrawal of consent and not included in the intention-to-treat primary analysis. The primary efficacy outcome occurred in five (3%) of 159 patients assigned to rivaroxaban and 15 (9%) of 159 patients assigned to no anticoagulation (relative risk 0·33, 95% CI 0·12–0·90; p=0·0293). No major bleeding occurred in either study group. Allergic reactions occurred in two (1%) patients in the rivaroxaban group. Interpretation In patients at high risk discharged after hospitalisation due to COVID-19, thromboprophylaxis with rivaroxaban 10 mg/day for 35 days improved clinical outcomes compared with no extended thromboprophylaxis. Funding Bayer.

Clinical experience for peripheral arterial disease treatment shows poor results when synthetic grafts are used to approach infrapopliteal arterial segments. However, tissue engineering may be an option to yield surrogate biocompatible neovessels. Thus, biological decellularized scaffolds could provide natural tissue architecture to use in tissue engineering, when the absence of ideal autologous veins reduces surgical options. The goal of this study was to evaluate different chemical induced decellularization protocols of the inferior vena cava of rabbits. They were decellularized with Triton X100 (TX100), sodium dodecyl sulfate (SDS) or sodium deoxycholate (DS). Afterwards, we assessed the remaining extracellular matrix (ECM) integrity, residual toxicity and the biomechanical resistance of the scaffolds. Our results showed that TX100 was not effective to remove the cells, while protocols using SDS 1% for 2h and DS 2% for 1h, efficiently removed the cells and were better characterized. These scaffolds preserved the original organization of ECM. In addition, the residual toxicity assessment did not reveal statistically significant changes while decellularized scaffolds retained the equivalent biomechanical properties when compared with the control. Our results concluded that protocols using SDS and DS were effective at obtaining decellularized scaffolds, which may be useful for blood vessel tissue engineering.

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IMPORTANCE Reticular veins are subdermal veins located in the lower limbs and are mainly associated with aesthetic complaints. Although sclerotherapy is the treatment of choice for reticular veins in the lower limbs, no consensus has been reached regarding to the optimal sclerosant.OBJECTIVE To compare the efficacy and safety of 2 sclerosants used to treat reticular veins: 0.2% polidocanol diluted in 70% hypertonic glucose (HG) (group 1) vs 75% HG alone (group 2). DESIGN, SETTING, AND PARTICIPANTS Prospective, randomized, triple-blind, controlled, parallel-group clinical trial with patients randomly assigned in a 1:1 ratio between the 2 treatment groups from March through December 2014, with 2 months' follow-up. The study was conducted in a single academic medical center. Eligible participants were all women, aged 18 to 69 years, who had at least 1 reticular vein with a minimum length of 10 cm in 1 of their lower limbs. INTERVENTIONSThe patients underwent sclerotherapy in a single intervention with either 0.2% polidocanol plus 70% HG or 75% HG alone to eliminate reticular veins. MAIN OUTCOMES AND MEASURESThe primary efficacy end point was the disappearance of the reticular veins within 60 days after treatment with sclerotherapy. The reticular veins were measured on images obtained before treatment and after treatment using ImageJ software. Safety outcomes were analyzed immediately after treatment and 7 days and 60 days after treatment and included serious adverse events (eg, deep vein thrombosis and systemic complications) and minor adverse events (eg, pigmentation, edema, telangiectatic matting, and hematomas).RESULTS Ninety-three women completed the study, median (interquartile range) age 43.0 (24.0-61.0) years for group 1 and 41.0 (27.0-62.0) years for group 2. Sclerotherapy with 0.2% polidocanol plus 70% HG was significantly more effective than with 75% HG alone in eliminating reticular veins from the treated area (95.17% vs 85.40%; P < .001). No serious adverse events occurred in either group. Pigmentation was the most common minor adverse event, with a 3.53% treated-vein pigmentation length for group 1 and 7.09% for group 2, with no significant difference between the groups (P = .09).CONCLUSIONS AND RELEVANCE Sclerotherapy with 0.2% polidocanol diluted in 70% HG was superior to 75% HG alone in sclerosing reticular veins, with no statistical difference for complications. Pigmentation occurred in both groups, with no statistical difference between them. No serious adverse events occurred in either group. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT02054325

194 ResumoObjetivo: Estudar prospectivamente a freqüência de complicações em pacientes tratados com warfarina e acompanhados no Ambulatório de Anticoagulação da Faculdade de Medicina de Botucatu da Universidade Estadual Paulista.Métodos: Pacientes sorteados entre os agendados para consulta de junho de 2002 a fevereiro de 2004. Na primeira consulta, foi preenchida ficha com dados de identificação e clínicos. A cada retorno, ou quando o paciente procurou o hospital por intercorrência, foi preenchida ficha com a razão normatizada internacional, existência e tipo de intercorrência e condições de uso dos antagonistas da vitamina K.Resultados: Foram acompanhados 136 pacientes (61 homens e 75 mulheres), 99 com tromboembolismo venoso e 37 com doença arterial; 59 pacientes eram de Botucatu, e 77, de outros municípios. Foram registradas 30 intercorrências: nove não relacionadas ao uso da warfarina e 21 complicações hemorrágicas (38,8 por 100 pacientes/ ano). Uma hematêmese foi considerada grave (1,9 por 100 pacientes/ ano). As demais foram consideradas moderadas ou leves. Não houve óbitos, hemorragia intracraniana ou necrose cutânea. A única associação significante foi da freqüência de hemorragia com nível médio de razão normatizada internacional.Conclusão: Nossos resultados mostram a viabilidade desse tratamento em pacientes vasculares em nosso meio, mesmo em população de baixo nível socioeconômico, quando tratados em ambulatório especializado.Palavras-chave: Anticoagulantes, warfarina, efeitos adversos, doenças vasculares, trombose venosa, embolia pulmonar. AbstractObjective: To prospectively study the frequency of complications in patients treated with warfarin followed at Botucatu Medical School.Methods: Patients randomly selected among those with appointments scheduled from June 2002 to February 2004. At the first appointment, a protocol was filled with identification and clinical data. At every return or when the patient went to the hospital due to clinical events, another form was filled with the international normalized ratio, existence and type of clinical event and the conditions of use of vitamin K antagonists.Results: A total of 136 patients (61 men and 75 women), were followed; 99 patients with venous thromboembolism and 37 with arterial disease; 59 were from Botucatu and 77 were from other municipalities. Thirty clinical events were registered: nine of them were not related to the use of warfarin and 21 were hemorrhagic complications (38.8 per 100 patients-year). One hematemesis was considered severe (1.9 per 100 patients-year). The others were considered moderate or mild. There were no deaths, intracranial hemorrhage or cutaneous necrosis. The only significant association was frequency of hemorrhage and average international normalized ratio level.Conclusion: Our results demonstrate the feasibility of this treatment in vascular patients in our country, even in socially and economically poor populations, when treated in specialized clinics.

Taken together, the use of decellularized bioscaffold and subcutaneous MSCs seems to be a potential approach to obtain bioengineered blood vessels, in the presence of EIGF supplementation.

Nota: Estas diretrizes se prestam a informar e não a substituir o julgamento clínico do médico que, em última análise, deve determinar o tratamento apropriado para seus pacientes.

Background The COVID-19 pandemic has made a significant impact on all spheres of society. The objective of this study was to examine the impact of COVID-19 on the practices, finances, and social aspects of Brazilian vascular surgeons’ lives. Methods This is a descriptive analysis of the responses from Brazilian vascular surgeons to the cross-sectional anonymous Society for Vascular Surgery Wellness Task Force Pandemic Practice, Anxiety, Coping, and Support Survey for Vascular Surgeons disseminated 14–24 April 2020. Survey dissemination in Brazil occurred mainly via the Brazilian Society of Angiology and Vascular Surgery (SBACV) and social media. The survey evaluated the impact of the COVID-19 pandemic on vascular surgeons’ lives by assessing COVID-19-related stressors, anxiety using theGeneral Anxiety Disorder (GAD)-7 scale, and coping strategies using the Brief Coping Orientation to Problems Experienced (Brief-COPE) inventory. Results A total of 452 responses were recorded from Brazil, with 335 (74%) respondents completing the entire survey. The majority of respondents were males ( N = 301, 67%) and practiced in an urban hospitals. The majority of respondents considered themselves at high risk to be infected with COVID-19 ( N = 251, 55.8%), and just over half the respondents noted that they had adequate PPE at their primary hospital ( N = 171, 54%). One hundred and nine (35%) surgeons confirmed that their hospitals followed professional surgical society guidelines for prioritizing surgeries during the pandemic. At the time of the survey, only 33 (10%) surgeons stated they have pre-operative testing of patients for COVID-19 available at their hospital. Academic vascular surgeons reported being redeployed more often to help with other non-vascular duties compared to community-based or solo practitioners (43% vs. 30% vs. 21% respectively, P = .01). Severe anxiety due to pandemic-related financial concerns was similar in those surgeons practicing solo compared to those in community- or academic-based/group practice (46% vs. 38% vs. 22%; P = .54). The respondents reported their anxiety levels as mild based on the stressors investigated instead of moderate-severe (54% vs. 46%; P = .04). Social media was utilized heavily during the pandemic, with video gatherings being the most commonly used tool (76%). Self-distraction (60%) and situational acceptance (81%) were the most frequently reported coping mechanisms used among Brazilian vascular surgeons. Conclusion The COVID pandemic has greatly affected healthcare providers around the world. At the time of this survey, Brazilian vascular surgeons are reporting low anxiety levels during this time and are using mostly active coping mechanisms.