Controversies in the pathophysiology of leg ulcers in sickle cell disease.

Patients with sickle cell disease (SCD) often experience painful vaso-occlusive crises and chronic haemolytic anaemia, as well as various acute and chronic complications, such as leg ulcers. Leg ulcers are characterized by their unpredictability, debilitating pain and prolonged healing process. The pathophysiology of SCD leg ulcers is not well defined. Known risk factors include male gender, poor social conditions, malnutrition and a lack of compression therapy when oedema occurs. Leg ulcers typically start with spontaneous pain, followed by induration, hyperpigmentation, blister formation and destruction of the epidermis. SCD is characterized by chronic haemolysis, increased oxidative stress and decreased nitric oxide bioavailability, which promote ischaemia and inflammation and consequently impair vascular function in the skin. This cutaneous vasculopathy, coupled with venostasis around the ankle, creates an ideal environment for local vaso-occlusive crises, which can result in the development of leg ulcers that resemble arterial ulcers. Following the development of the ulcer, healing is hindered as a result of factors commonly observed in venous ulceration, including venous insufficiency, oedema and impaired angiogenesis. All of these factors are modulated by genetic factors. However, our current understanding of these genetic factors remains limited and does not yet enable us to accurately predict ulceration susceptibility.

The obstetrical consequences of ischemic stroke in women of childbearing age.

PURPOSE: Although recurrence risk is a major concern for women having had an ischemic stroke (IS) and who are planning a pregnancy, studies on recurrence risk and pregnancy outcomes are scarce and heterogeneous. METHODS: This retrospective study assessed women aged 15-44 years with a diagnosis of ischemic stroke admitted in the Lyon Stroke Centre, France, between January 2009 and December 2013. The primary outcome was stroke recurrence during pregnancy or the post-partum period. Secondary outcomes were pregnancy complications. RESULTS: Overall, 104 women with a prior ischemic stroke were included. Mean age at the time of the stroke was 36 ± 6.7 years old. Stroke etiology was large-artery atherosclerosis for 1 woman, cardioembolism for 23 women, and undetermined for 55 women. No antiphospholipid syndrome was found. Among them, 29 women had 58 subsequent pregnancies. Overall, there were three IS recurrence (2.9%), but none occurred during pregnancy. There were 27 miscarriages (47% of pregnancies), two pre-eclampsia (3%), and one stillbirth (1.7%). CONCLUSIONS: We observed no recurrence of IS during pregnancy. The study also highlighted that the risk of miscarriages was higher than general population and that of stillbirth should be further studied.

Outcomes of venous thromboembolism in patients with inherited thrombophilia treated with direct oral anticoagulants: insights from the RIETE registry.

While direct oral anticoagulants (DOACs) are frequently used to treat venous thromboembolism (VTE), the outcomes of patients with inherited thrombophilia (IT) receiving DOACs for VTE remain understudied. We used data from the international RIETE registry to compare the rates of VTE recurrences, major bleeding, and mortality during anticoagulant treatment in VTE patients with and without IT, grouped by the use of DOACs or standard anticoagulant therapy. Among 103,818 enrolled patients, 21,089 (20.3%) were tested for IT, of whom 8422 (39.9%) tested positive: Protein C deficiency 294, Protein S deficiency 726, Antithrombin deficiency 240, Factor V Leiden 2248, Prothrombin gene mutation 1434, combined IT 3480. Overall, 14,189 RIETE patients (6.2% with IT) received DOACs, and 89,629 standard anticoagulation (8.4% with IT), mostly with heparins followed by vitamin K antagonists. Proportions of patients receiving DOACs did not differ between IT-positive and IT-negative patients. Rates of VTE recurrence on anticoagulant treatment were highest in patients with AT deficiency (P < 0.01). Rates of on-treatment major bleeding and all-cause mortality were lowest among patients with Factor V Leiden (FVL) or PT G20210A mutations, compared with patients who tested negative. Patients with IT who received DOACs had lower rates of major bleeding than those receiving standard anticoagulation. Excluding FVL and Protein S deficiency, patients with IT had lower rates of VTE recurrence with DOACs than with standard anticoagulation. DOACs are equally safe and effective in VTE patients with IT, with lower bleeding rates than those on standard anticoagulation.

An angiosome-centred approach for TcpO2 electrode positioning.

Background: The latest guidelines propose a TcpO2 value of 30 mmHg to help to confirm the diagnosis of chronic limb threatening ischemia. However, placement of electrodes is not standardised. The relevance of an "angiosome-centred" approach for TcpO2 electrode positioning has never been evaluated. We therefore retrospectively analysed our TcpO2 results to study the impact of electrode placement on the different angiosomes of the foot. Patients and methods: Patients consulting the vascular medicine department laboratory for suspicion of CLTI using TcpO2 electrodes placement on the different angiosome arteries of the foot (first inter metatarsal space, lateral edge of the foot and plantar side of the foot) were included. As the mean intra-individual variation is reported to be 8 mmHg, a variation of mean TcpO2 for the 3 locations ≤8 mmHg was considered to be not clinically significant. Results: Thirty-four patients (34 ischemic legs) were analysed. The mean TcpO2 was higher at the lateral edge of the foot (55 mmHg) and plantar side of the foot (65 mmHg) than at the first intermetatarsal space (48 mmHg). There was no clinically significant variation of mean TcpO2 according to anterior/posterior tibial artery patency and fibular artery patency. This was present when stratifying on the number of patent arteries. Conclusions: The present study suggests that multi-electrode TcpO2 is not useful to assess tissue oxygenation in the different angiosomes of the foot to guide surgical decision; first intermetatarsal electrode alone would be preferred. TcpO2 seems rather to evaluate overall tissue oxygenation of the foot. Electrode location on the plantar side of the foot may overestimate results and lead to misinterpretation.

Deep vein thrombosis symptoms and 30-day mortality in acute pulmonary embolism.

BACKGROUND: In patients with acute symptomatic pulmonary embolism (PE), the presence of concomitant lower-limb deep vein thrombosis (DVT) has been associated with a higher mortality rate. The prognostic significance of DVT symptoms among these patients remains uncertain. METHODS: We used the RIETE (Registro Informatizado de Enfermedad TromboEmbólica) registry to compare the 30-day mortality rate in patients with PE and concomitant lower-limb DVT, according to the presence or absence of DVT symptoms. Primary outcomes were all-cause death and PE-related death within the first 30 days. RESULTS: Since March 2001 to June 2021, there were 17,742 patients with acute symptomatic PE and objectively proven concomitant lower-limb DVT. Of these, 11,984 (68%) had DVT symptoms. Most patients with or without DVT symptoms (82% vs. 81%) received low-molecular-weight heparin initially. Then, most (61% vs. 58%) switched to vitamin K antagonists. During the first 30 days of therapy, 497 patients with DVT symptoms (4.1%) and 164 (2.8%) with no DVT symptoms died (rate ratio [RR]: 1.48; 95%CI: 1.23-1.77). The rates of PE-related death were: 1.0% vs. 0.7%, respectively (RR: 1.50; 95%CI: 1.04-2.16). On multivariable analysis, patients with DVT symptoms were at increased risk for all-cause death (adjusted hazard ratio [aHR]: 1.49; 95%CI: 1.24-1.78), and PE-related death (aHR: 1.52; 95%CI: 1.05-2.20). CONCLUSION: Among patients with acute symptomatic PE and concomitant lower-limb DVT, those with DVT symptoms had an increased all-cause and PE-related mortality within 30 days. Assessment of DVT symptoms would assist with risk stratification of these patients.

Major gastrointestinal bleeding in patients receiving anticoagulant therapy for venous thromboembolism.

INTRODUCTION: The gastrointestinal (GI) tract is a frequent site of bleeding in patients receiving anticoagulant therapy for venous thromboembolism (VTE). At-risk patients have not been consistently identified yet. METHODS: We used the RIETE registry to assess the clinical characteristics of patients developing major GI bleeding during the course of anticoagulation. Then, we built a predictive score based on multivariable analysis, aiming to identify patients at increased risk for major GI bleeding. RESULTS: We included 87,431 patients with acute VTE. During the course of anticoagulation, 778 (0.89%) suffered major GI bleeding, 815 (0.93%) non-major GI bleeding and 1462 (1.67%) had major bleeding outside the GI tract. During the first 30 days after major GI bleeding, 7.6% of patients re-bled, 3.9% had VTE recurrences and 33% died. On multivariable analysis, male sex, age ≥70 years, initial VTE presentation as pulmonary embolism, active cancer, prior VTE, recent major bleeding in the GI tract, esophageal varicosities, anemia, abnormal prothrombin time, renal insufficiency and use of corticosteroids were associated to an increased risk for major GI bleeding. Using the predictive score, 39,591 patients (45%) were at low risk; 36,602 (42%) at intermediate-risk; 9315 (11%) at high-risk; and 1923 (2.2%) at very high risk. Their rates of major GI bleeding were: 0.21%, 0.96%, 2.41% and 6.08%, respectively. The c-statistics was 0.771 (95%CI. 0.755-0.786). CONCLUSIONS: We have developed a score which has the potential to identify patients at increased risk for GI bleeding, but needs to be externally validated."

Increased blood viscosity and red blood cell aggregation in patients with COVID-19.

The aim of this study was to (1) analyze blood viscosity, red blood cell (RBC) deformability, and aggregation in hospitalized patients with Coronavirus disease 19 (COVID-19); (2) test the associations between impaired blood rheology and blood coagulation; and (3) test the associations between impaired blood rheology and several indicators of clinical severity. A total of 172 patients with COVID-19, hospitalized in COVID-unit of the Internal Medicine Department (Lyon, France) participated in this study between January and May 2021. Clinical parameters were collected for each patient. Routine hematological/biochemical parameters, blood viscosity, RBC deformability and aggregation, and RBC senescence markers were measured on the first day of hospitalization. A control group of 38 healthy individuals was constituted to compare the blood rheological and RBC profile. Rotational thromboelastography was performed in 76 patients to study clot formation dynamics. Our study demonstrated that patients with COVID-19 had increased blood viscosity despite lower hematocrit than healthy individuals, as well as increased RBC aggregation. In-vitro experiments demonstrated a strong contribution of plasma fibrinogen in this RBC hyper-aggregation. RBC aggregation correlated positively with clot firmness, negatively with clot formation time, and positively with the length of hospitalization. Patients with oxygen supplementation had higher RBC aggregation and blood viscosity than those without, and patients with pulmonary lesions had higher RBC aggregation and enhanced coagulation than those without. This study is the first to demonstrate blood hyper-viscosity and RBC hyper-aggregation in a large cohort of patients with COVID-19 and describe associations with enhanced coagulation and clinical outcomes.

Reference Probe for TcpO2 at Rest: A Systematic Review.

(1) Background: Transcutaneous oxygen pressure (TcpO2) is used to determine the severity of lower extremity arterial disease (LEAD). Many authors used a ratio of limb to chest TcpO2, also called the regional perfusion index (RPI), which should be independent of variations in oxygen delivery and reflective of local limb oxygen supply. The relevance of a reference probe-positioned TcpO2 electrode is debated. We aimed to review the relevance of the reference probe in previous studies using rest TcpO2. (2) Methods: We searched Medline and the Cochrane Central Register of Controlled Trials on 22 September 2022 using keywords related to TcpO2, reference probe and LEAD. (3) Results/Discussion: Fifteen studies were included in the review. Nine studies investigated LEAD severity (n = 9), amputation healing predication (n = 4), surgical outcome prediction (n = 2), therapeutic effect (n = 3) and difference according to diabetic status (n = 1). Four studies investigated more than 1 indication. Among 12 (16.7%) studies using RPI, only two authors found a benefit of using RPI instead of absolute TcpO2. Using only univariate analysis, one author reported that RPI was significantly related to viability at 1 year, while distal TcpO2 was not, on 13 limbs. The following year, the same author published a new study including 118 limbs that reported that RPI and absolute TcPO2 were both prognostic factors for limb viability at 1 year using a multivariate model. (4) Conclusions: Only one study firmly supporting the use of RPI, calculated using a reference probe on the arm, to predict BKA healing. Prospective studies are needed to validate this result; for other indications there is insufficient data supporting the use of a TcpO2 reference probe at rest.

Management of acute venous thromboembolism in patients taking antiplatelet therapy.

BACKGROUND: Concomitant anticoagulant and antiplatelet therapy increases bleeding risk, but most data are derived from patients with atrial fibrillation. Patients with venous thromboembolism (VTE) may differ. OBJECTIVE: To study the management of patients diagnosed with acute VTE while receiving antiplatelet treatment. The primary outcome was the number of patients discharged with concomitant therapy. Secondary outcomes were clinically relevant bleeding, cardiovascular events, recurrent VTE and death during follow-up, according to discharge therapy. METHODS: We performed a post-hoc analysis of patients included in two prospective registries, sharing the same case report form, from 2007 to 2017. RESULTS: Among the 1694 identified patients, 254 (15.0%) were receiving antiplatelet treatment at VTE diagnosis, of whom 61 (24.0%) were discharged with concomitant anticoagulant and antiplatelet therapy. In multivariable analysis, age ≥ 80 years-old and the use of Direct Oral Anticoagulants for VTE therapy were associated with the decision to stop the antiplatelet, while having dual anti-platelet therapy at baseline, a history of coronaropathy or peripheral arterial disease were associated with concomitant anticoagulant and antiplatelet therapy. The decision to stop antiplatelet was associated with a non-significant 46% decrease in the risk of bleeding (OR 0.54 (0.16; 1.78)), and a non-significant 68% increase in the risk of cardiovascular events (OR 1.68 (0.44; 6.46)). CONCLUSION: At acute VTE diagnosis, over 15% of patients were receiving antiplatelet agents, of whom 24% were discharged with concomitant anticoagulant and antiplatelet therapy. This therapeutic decision may be associated with a lower risk of cardiovascular events, but an increased risk of bleeding.

What Is Currently the Role of TcPO2 in the Choice of the Amputation Level of Lower Limbs? A Comprehensive Review.

Some patients still require major amputation for lower extremity peripheral arterial disease treatment. The purpose of pre-operative amputation level selection is to determine the most distal amputation site with the highest healing probability without re-amputation. Transcutaneous oximetry (TcPO2) can detect viable tissue with the highest probability of healing. Several factors affect the accuracy of TcPO2; nevertheless, surgeons rely on TcPO2 values to determine the optimal amputation level. Background about the development of TcPO2, methods of measurement, consequences of lower limb amputation level, and the place of TcPO2 in the choice of the amputation level are reviewed herein. Most of the retrospective studies indicated that calf TcPO2 values greater than 40 mmHg were associated with a high percentage of successful wound healing after below-knee-amputation, whereas values lower than 20 mmHg indicated an increased risk of unsuccessful healing. However, a consensus on the precise cut-off value of TcPO2 necessary to assure healing is missing. Ways of improvement for TcPO2 performance applied to the optimization of the amputation-level are reported herein. Further prospective data are needed to better approach a TcPO2 value that will promise an acceptable risk of re-amputation. Standardized TcPO2 measurement is crucial to ensure quality of data.

Presenting Characteristics, Treatment Patterns, and Outcomes among Patients with Venous Thromboembolism during Hospitalization for COVID-19.

Venous thromboembolism (VTE) is common in patients with coronavirus disease-2019 (COVID-19). However, limited data exist on patient characteristics, treatments, and outcomes. To describe the clinical characteristics, treatment patterns, and short-term outcomes of patients diagnosed with VTE during hospitalization for COVID-19. This is a prospective multinational study of patients with incident VTE during the course of hospitalization for COVID-19. Data were obtained from the Registro Informatizado de la Enfermedad TromboEmbólica (RIETE) registry. All-cause mortality, VTE recurrences, and major bleeding during the first 10 days were separately investigated for patients in hospital wards versus those in intensive care units (ICUs). As of May 03, 2020, a total number of 455 patients were diagnosed with VTE (83% pulmonary embolism, 17% isolated deep vein thrombosis) during their hospital stay; 71% were male, the median age was 65 (interquartile range, 55-74) years. Most patients (68%) were hospitalized in medical wards, and 145 in ICUs. Three hundred and seventeen (88%; 95% confidence interval [CI]: 84-91%) patients were receiving thromboprophylaxis at the time of VTE diagnosis. Most patients (88%) received therapeutic low-molecular-weight heparin, and 15 (3.6%) received reperfusion therapies. Among 420 patients with complete 10-day follow-up, 51 (12%; 95% CI: 9.3-15%) died, no patient recurred, and 12 (2.9%; 95% CI: 1.6-4.8%) experienced major bleeding. The 10-day mortality rate was 9.1% (95% CI: 6.1-13%) among patients in hospital wards and 19% (95% CI: 13-26%) among those in ICUs. This study provides characteristics and early outcomes of patients diagnosed with acute VTE during hospitalization for COVID-19. Additional studies are needed to identify the optimal strategies to prevent VTE and to mitigate adverse outcomes associated.

Severe renal impairment and risk of bleeding during anticoagulation for venous thromboembolism.

BACKGROUND: Detection of severe renal impairment in patients with venous thromboembolism (VTE) is mandatory both for selecting anticoagulant therapy and for evaluating major bleeding risk, increased by severe renal impairment. OBJECTIVES: To determine whether the Cockcroft and Gault (CG) and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formulas identify severe renal impairment in the same VTE patients presenting the same risk of major bleeding. PATIENTS/METHODS: We compared clinical characteristics and outcomes during the first 3 months of anticoagulation between VTE patients in the RIETE registry with severe renal impairment according to the CG and/or CKD-EPI formula (estimated glomerular filtration rate <30 mL/min and <30 mL/min/1.73 m2 , respectively). The primary outcome was major bleeding. RESULTS: Up to October 2017, 41 796 patients were included in RIETE. Among the 4676 patients with severe renal impairment according to at least one of the formulas, this was not confirmed by the other formula in 1904 (40.7%). Major bleeding risk was increased in every patient subgroup with severe renal impairment vs patients without this condition (CG or CKD-EPI < 30: odds ratio [OR] = 2.26, 95% confidence interval [CI 2.01-2.53], only CG < 30: OR = 1.72, 95% CI [1.37-2.13], only CKD-EPI < 30: OR = 2.34, 95% CI [1.77-3.05], CG+CKD-EPI < 30: OR = 2.47, 95% CI [2.16-2.83], all vs CG+CKD-EPI > 30). CONCLUSION: The CG and CKD-EPI formulas identify different subgroups of patients with severe renal impairment, leading to discordant results in 40.7% of these patients. Irrespective of the formula used for their identification, patients with severe renal impairment have a higher risk of major bleeding under anticoagulant therapy.