Practical Suggestions for an Optimal Management of Vitamin K Antagonists: Italian Federation of Centers for the Diagnosis of Thrombotic Disorders and the Surveillance of the Antithrombotic Therapies (FCSA) Position Paper.

In the era of direct oral anticoagulants, vitamin K antagonists retain a clinically relevant role in thrombotic disorders. In Italy, approximately 20% of the patients on anticoagulant therapies receives a VKA, in most cases warfarin. The optimal management of this drug is challenging and cannot disregard its intricate and unpredictable pharmacokinetic properties and patient's thrombotic and bleeding risk. Several clinical issues encountered during warfarin treatment are still unanswered and are tentatively addressed by physicians. In this regard, the Italian Federation of Centers for the diagnosis of thrombotic disorders and the Surveillance of the Antithrombotic therapies (FCSA) provides some experience-based good clinical practice's suggestions on the following topics: (1) how to start the anticoagulant treatment with warfarin and warfarin induction regimen; (2) how to manage a subtherapeutic INR value; (3) how to manage a supratherapeutic INR value in asymptomatic patients; and (4) how to manage the association of warfarin with interfering drugs.

[Ten questions related to heparin-induced thrombocytopenia]. / Dieci quesiti in tema di trombocitopenia indotta da eparina.

Heparin-induced thrombocytopenia (HIT) is a potentially fatal, immune-mediated adverse drug reaction to heparin (both unfractionated and low molecular weight heparin) which is caused by the formation of IgG antibodies against an epitope composed by platelet-derived PF4 and heparin. Binding of IgG to PF4/heparin neoantigen induces platelet activation which may cause venous or arterial thrombosis, associated with thrombocytopenia. HIT diagnosis is based on both pre-test clinical probability evaluation and the detection of platelet activating antibodies. Laboratory diagnosis is based on immunologic and functional assays. When HIT is diagnosed any type of heparin should be stopped immediately and non-heparin alternative anticoagulant must be started in order to halt the pro-thrombotic process. Argatroban and danaparoid are currently the only drugs approved for HIT treatment. Bivalirudin and fondaparinux are also used for the treatment of this rare but severe condition.

Management of DOAC in Patients Undergoing Planned Surgery or Invasive Procedure: Italian Federation of Centers for the Diagnosis of Thrombotic Disorders and the Surveillance of the Antithrombotic Therapies (FCSA) Position Paper.

Patients on anticoagulant treatment are constantly increasing, with an estimated prevalence in Italy of 2% of the total population. About a quarter of the anticoagulated patients require temporary cessation of direct oral anticoagulants (DOACs) or vitamin K antagonists for a planned intervention within 2 years from anticoagulation inception. Several clinical issues about DOAC interruption remain unanswered: many questions are tentatively addressed daily by thousands of physicians worldwide through an experience-based balancing of thrombotic and bleeding risks. Among possible valuable answers, the Italian Federation of Centers for the diagnosis of thrombotic disorders and the Surveillance of the Antithrombotic therapies (FCSA) proposes some experience-based suggestions and expert opinions. In particular, FCSA provides practical guidance on the following issues: (1) multiparametric assessment of thrombotic and bleeding risks based on patients' individual and surgical risk factor, (2) testing of prothrombin time, activated partial thromboplastin time, and DOAC plasma levels before surgery or invasive procedure, (3) use of heparin, (4) restarting of full-dose DOAC after high risk bleeding surgery, (5) practical nonpharmacological suggestions to manage patients perioperatively. Finally, FCSA suggests creating a multidisciplinary "anticoagulation team" with the aim to define the optimal perioperative management of anticoagulation.

[Thrombosis and COVID-19 vaccine: much ado about nothing?] / Trombosi secondaria a vaccinazione anti-COVID-19: un reale rischio clinico o tanto rumore per nulla?

Several cases of thrombosis in unusual sites associated with thrombocytopenia have been described after vaccination with the recombinant adenoviral vector encoding the spike protein antigen of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), ChAdOx1 nCov-19 (AstraZeneca) and Ad26.COV.2 (Johnson & Johnson/Janssen). This new clinical entity has many analogies with heparin-induced thrombocytopenia, and recent studies suggest that an immunologic mechanism may be implicated in the pathogenesis of this unusual thrombotic disorder. However, more data are needed to identify subjects at risk for this rare clotting disease.

Time in therapeutic range is lower in women than in men and is not explained by differences in age or comorbidity.

BACKGROUND: Time in therapeutic range (TTR) measures the stability of the international normalized ratio in patients on vitamin K antagonists (VKA). Low values are associated with poor outcomes. Women were shown to have lower TTR than men, but the causes are poorly defined. It was suggested that women on VKA are older and more morbid than men, and this could affect the stability of anticoagulation. We aimed to identify variables that affect TTR differently in women and men. MATERIALS AND METHODS: This is a retrospective study in patients referred to a University hospital anticoagulant clinic. Age, sex, comorbidities, number of daily medications, indication and type of anticoagulant, weekly dosage and distribution, were derived from electronic records. Differences by sex and regression analysis to identify significant modulators of TTR were computed. RESULTS: 1182 women and 1281 men on VKA were studied. Women were older than men (81.5 yrs. ± 11.2 vs 78.4 yrs. ± 12.2), and had lower TTR (65% ± 20.3 vs 69% ± 19.8). Comorbidity was similar between sexes and negatively affected TTR in both. Mechanical valves as an indication to anticoagulation and acenocoumarol as an anticoagulant as opposed to warfarin had a strong negative influence on TTR, while age increased TTR. Being a man rather than a woman afforded more than three TTR points. Number of medications and average anticoagulant dose were equal between sexes. DISCUSSION: Women have a lower TTR than men, on average below the safety threshold. They were indeed older, but age positively influenced TTR. Since women and men were equally comorbid, neither age nor disease explains differences in TTR. None of the other variables included in the study could explain the gender gap in TTR. Since women are at increased risk of cardioembolic stroke in atrial fibrillation, an effort at defining other causes for the observed differences, closer monitoring and switching to direct anticoagulants whenever possible is warranted.

Autologous platelet-rich plasma in the treatment of refractory corneal ulcers: A case report.

PURPOSE: To evaluate the efficacy of a low-cost preparation of platelet-rich plasma (PRP) eye drops in the treatment of persistent non-infectious corneal ulcer. OBSERVATIONS: A 67-year-old female presented to our clinic with a wide corneal ulcer and severe paracentral corneal thinning refractory to medical therapy with antibiotics, lubricant and contact lens bandage. The patient received a novel preparation of PRP solution. After 15 days of therapy, we observed complete resolution of the corneal ulcer with regrowth of the epithelium and a reduction in corneal opacity. CONCLUSION AND IMPORTANCE: Although the low-cost PRP preparation gives a lower platelet concentration than standard procedures, our work shows this preparation to be effective in the treatment of refractory non-infectious corneal ulcer.

Managing anticoagulation in the COVID-19 era between lockdown and reopening phases.

Patients on anticoagulant treatment are constantly increasing, with an estimated prevalence in Italy of 2% of the total population. The recent spreadout of the COVID-19 pandemic requires a re-organization of Anticoagulation Clinics to prevent person-to-person viral diffusion and continue to offer the highest possible quality of assistance to patients. In this paper, based on the Italian Federation of Anticoagulation Clinics statements, we offer some advice aimed at improving patient care during COVID-19 pandemic, with particular regard to the lockdown and reopening periods. We give practical guidance regarding the following points: (1) re-thinking the AC organization, (2) managing patients on anticoagulants when they become infected by the virus, (3) managing anticoagulation surveillance in non-infected patients during the lockdown period, and (4) organizing the activities during the reopening phases.

Low levels of ADAMTS-13 with high anti-ADAMTS-13 antibodies during remission of immune-mediated thrombotic thrombocytopenic purpura highly predict for disease relapse: A multi-institutional study.

Immune-mediated thrombotic thrombocytopenic purpura (iTTP) is a life-threatening immune-mediated thrombotic microangiopathy. Daily therapeutic plasma exchange (TPE) and the optimized use of rituximab have strikingly improved the outcome of this disease, however the rate of disease recurrence remains high. Specific predictors of relapse in patients in remission can be relevant for an optimal patient management. In this study, we aimed to identify predictive variables of disease relapse in a multicenter cohort of 74 out of 153 iTTP patients. They were tested at different time points during remission for the levels of ADAMTS-13 activity and autoantibody, and did not receive pre-emptive treatment for ADAMTS-13 activity deficiency during remission. The results showed that the association of ADAMTS13 activity ≤20% with a high anti-ADAMTS-13 titer at remission, and the time to response to first line treatment ≥13 days, were independent predictive factors of disease relapse. In addition, the use of rituximab in patients with exacerbation or refractoriness to TPE was significantly associated with reduced relapse rate. By Cox regression analysis, patients with ADAMTS-13 activity ≤20% plus anti-ADAMTS13 antibody titer ≥15 U/mL at remission had an increased risk of relapse (HR 1.98, CI 95% 1.087-3.614; P < .02). These findings may help to outline more personalized therapeutic strategies in order to provide faster and sustained responses to first-line iTTP treatment and prevent relapses in these patients.

The Many Faces of Covid-19 at a Glance: A University Hospital Multidisciplinary Account From Milan, Italy.

In March 2020, northern Italy became the second country worldwide most affected by Covid-19 and the death toll overtook that in China. Hospital staff soon realized that Covid-19 was far more severe than expected from the few data available at that time. The Covid-19 pandemic forced hospitals to adjust to rapidly changing circumstances. We report our experience in a general teaching hospital in Milan, the capital of Lombardy, the most affected area in Italy. First, we briefly describe Lombardy's regional Covid-19-related health organizational changes as well as general hospital reorganization. We also provide a multidisciplinary report of the main clinical, radiological and pathological Covid-19 findings we observed in our patients.

The Role of Tissue Factor in Atherothrombosis and Coronary Artery Disease: Insights into Platelet Tissue Factor.

The contribution of vessel wall-derived tissue factor (TF) to atherothrombosis is well established, whereas the pathophysiological relevance of the blood-borne TF is still a matter of debate, and controversies on the presence of platelet-associated TF still exist. In the past 15 years, several studies have documented the presence of TF in human platelets, the capacity of human platelets to use TF mRNA to make de novo protein synthesis, and the increase in the percentage of TF positive platelets in pathological conditions such as coronary artery disease (CAD). The exposure of vessel wall-derived TF at the site of vascular injury would play its main role in the initiation phase, whereas the blood-borne TF carried by platelets would be involved in the propagation phase of thrombus formation. More recent data indicate that megakaryocytes are committed to release into the bloodstream a well-defined number of TF-carrying platelets, which represents only a fraction of the whole platelet population. These findings are in line with the evidence that platelets are heterogeneous in their functions and only a subset of them is involved in the hemostatic process. In this review we summarize the existing knowledge on platelet associated TF and speculate on its relevance to physiology and to atherothrombosis and CAD.

Implementation of non-vitamin K antagonist oral anticoagulants in daily practice: the need for comprehensive education for professionals and patients.

Non-vitamin K antagonist oral anticoagulants (NOACs) are increasingly used for the prevention and treatment of venous thromboembolism and for stroke prevention in patients with atrial fibrillation. NOACs do not require routine coagulation monitoring, creating a challenge to established systems for patient follow-up based on regular blood tests. Healthcare professionals (HCPs) are required to cope with a mixture of patients receiving either a vitamin K antagonist or a NOAC for the same indications, and both professionals and patients require education about the newer drugs. A European working group convened to consider the challenges facing HCPs and healthcare systems in different countries and the educational gaps that hinder optimal patient management. Group members emphasised the need for regular follow-up and noted national, regional and local variations in set-up and resources for follow-up. Practical incorporation of NOACs into healthcare systems must adapt to these differences, and practical follow-up that works in some systems may not be able to be implemented in others. The initial prescriber of a NOAC should preferably be a true anticoagulation specialist, who can provide initial patient education and coordinate the follow-up. The long-term follow-up care of patients can be managed through specialist coagulation nurses, in a dedicated anticoagulation clinic or by general practitioners trained in NOAC use. The initial prescriber should be involved in educating those who perform the follow-up. Specialist nurses require access to tools, potentially including specific software, to guide systematic patient assessment and workflow. Problem cases should be referred for specialist advice, whereas in cases for which minimal specialist attention is required, the general practitioner could take responsibility for patient follow-up. Hospital departments and anticoagulation clinics should proactively engage with all downstream HCPs (including pharmacists) to ensure their participation in patient management and reinforcement of patient education at every opportunity. Ideally, (transmural) protocols for emergency situations should be developed. Last but not least, patients should be well-informed about their condition, the treatment, possible risk scenarios, including the consequences of non-adherence to prescribed therapy, and the organisation of follow-up care.

Human megakaryocytes confer tissue factor to a subset of shed platelets to stimulate thrombin generation.

Tissue factor (TF), the main activator of the blood coagulation cascade, has been shown to be expressed by platelets. Despite the evidence that both megakaryocytes and platelets express TF mRNA, and that platelets can make de novo protein synthesis, the main mechanism thought to be responsible for the presence of TF within platelets is through the uptake of TF positive microparticles. In this study we assessed 1) whether human megakaryocytes synthesise TF and transfer it to platelets and 2) the contribution of platelet-TF to the platelet hemostatic capacity. In order to avoid the cross-talk with circulating microparticles, we took advantage from an in vitro cultured megakaryoblastic cell line (Meg-01) able to differentiate into megakaryocytes releasing platelet-like particles. We show that functionally active TF is expressed in human megakaryoblasts, increased in megakaryocytes, and is transferred to a subset of shed platelets where it contributes to clot formation. These data were all confirmed in human CD34pos-derived megakaryocytes and in their released platelets. The effect of TF silencing in Meg-megakaryoblasts resulted in a significant reduction of TF expression in these cells and also in Meg-megakaryocytes and Meg-platelets. Moreover, the contribution of platelet-TF to the platelet hemostatic capacity was highlighted by the significant delay in the kinetic of thrombin formation observed in platelets released by TF-silenced megakaryocytes. These findings provide evidences that TF is an endogenously synthesised protein that characterises megakaryocyte maturation and that it is transferred to a subset of newly-released platelets where it is functionally active and able to trigger thrombin generation.

Seroprevalence of West Nile virus antibodies in blood donors living in the metropolitan area of Milan, Italy, 2009-2011.

A seroprevalence study for anti-West Nile virus-specific antibodies was carried out in healthy blood donors resident in the metropolitan area of Milan in two different years, 2009 and 2011. In 2009 no positive sera were found, whereas 5 positive sera were found in 2011, revealing viral circulation in this naive area. The seroprevalence rate identified in 2011 was 0.57%, suggesting that the area of WNV circulation in Italy is larger than that previously identified.

[Impact of anemia and its treatment in patients with acute coronary syndromes]. / Significato prognostico e trattamento dell'anemia nei pazienti con sindrome coronarica acuta.

Anemia has been reported in 15-30% of patients with acute coronary syndrome. This percentage is even higher during the in-hospital phase, when hemoglobin tends to reach a "nadir" value, and usually a larger number of anemic patients compared to admission are discharged from the hospital. Both retrospective evaluation of randomized clinical trials and data coming from prospective or retrospective observational studies have prompted out a direct relationship between anemia and adverse outcomes in acute coronary syndrome patients. Although anemia has the potential to worsen the myocardial ischemic insult in acute coronary syndromes, it is not yet clear whether it is responsible per se for a higher incidence of death and myocardial infarction or it behaves just like an additional risk factor. Blood transfusions may correct anemia but also accentuate rather than attenuate both short-term and long-term rates of major adverse cardiac events, suggesting the opportunity of a restrictive use of this therapy in patients with low levels of hemoglobin who are hemodynamically stable.

Inhibitors of propagation of coagulation: factors V and X.

Cardiovascular diseases are still the most important cause of morbidity and mortality in western countries and antithrombotic treatment is nowadays widely used. Drugs able to reduce coagulation activation are the treatment of choice for a number of arterial and/or venous thromboembolic conditions. Some of the drugs currently used for this purpose, such as heparins (UFH or LMWH) and VKA, have limitations consisting of a narrow therapeutic window and an unpredictable response with the need of laboratory monitoring in order to assess their efficacy and safety. These drawbacks have stimulated an active research aimed to develop new drugs able to act on single factors involved in the coagulation network, with predictable response. Intense experimental and clinical work on new drugs has focused on synthetic agents, which could preferably be administered orally and at fixed doses. The most advanced clinical development with new anticoagulants has been achieved for those inhibiting FXa and some of them, like fondaparinux, are already currently used in clinical practice. Other agents, such as rivaroxaban, apixaban, otamixaban and edoxaban are under development and have already been studied or are currently under investigation in large scale phase III clinical trials for prevention and treatment of venous thromboembolism, atrial fibrillation and acute coronary syndromes. Some of them have proved to be more effective than conventional therapy. Data on some agents inhibiting FVa are still preliminary and some of these drugs have so far been considered only in patients with disseminated intravascular coagulation secondary to sepsis.

OBI-1, porcine recombinant Factor VIII for the potential treatment of patients with congenital hemophilia A and alloantibodies against human Factor VIII.

Hemophilia A is caused by a deficiency in blood coagulation Factor (F)VIII. Treatment for acute bleeding in patients comprises prophylactic infusion with human plasma-derived (pd) or recombinant (r)FVIII to increase circulating FVIII levels. However, alloantibodies (inhibitor) may arise in patients, limiting the efficacy of replacement therapy, especially in patients who develop high-titer inhibitors. For these patients, FVIII-bypassing agents are proposed, but there is a rare risk of thrombotic events. Porcine pdFVIII successfully achieves hemostatic FVIII levels in patients in whom human FVIII was ineffective, but possible residual viral contamination and immunogenicity prevents routine use. OBI-1, being developed by Ipsen and Inspiration Biopharmaceuticals Inc, is a bioengineered form of porcine rFVIII that is highly purified. OBI-1 has the procoagulant and biochemical properties of porcine pdFVIII, with improvements in risk of toxicity, infection and ease of manufacture. OBI-1 demonstrated significantly less immunogenicity than pdFVIII in a murine model of hemophilia A. Moreover, in cynomolgus monkeys, OBI-1 did not generate detectable inhibitors. OBI-1 was effective in a phase II, open-label clinical trial in patients with hemophilia A and inhibitor against porcine FVIII, who were experiencing a non-life or -limb threatening bleed. OBI-1 was well tolerated, without drug-related serious adverse events and is promising for further studies.

Diagnosis, laboratory aspects and management of acquired hemophilia A.

Acquired hemophilia A (AHA) is a rare autoimmune disease, characterized by severe, often life-threatening hemorrhages in patients without a prior history of bleeding disorder. It most frequently occurs in the elderly, and may be associated with other clinical conditions, such as cancer, autoimmune diseases, pregnancy or without a relevant cause. Diagnosis and correct therapy are crucial for the patient's outcome. Management of the disease consists of gaining immediate control of acute bleeding and the starting of an immunosuppressive therapy in order to eradicate the anti-factor VIII autoantibody. Factor VIII bypassing agents, such as prothrombin complex concentrates or recombinant activated factor VII, have proven effective in bleeding control, whereas the combined therapy of cyclophosphamide and corticosteroids seems to be, at present, the best immunosuppressive option. Other treatments including Rituximab, immunoadsorption or induction of immune tolerance are still experimental, and need to be validated through controlled clinical trials.

Clinical implications and management of bleeding events in patients with acute coronary syndromes.

In the past decades, there has been a significant development in the management of patients with acute coronary syndromes (ACS), largely driven by advances in antithrombotic and antiplatelet agents. Despite significant improvements in efficacy end points such as death, myocardial infarction and repeated revascularization, these therapies are still associated with a significant risk of bleeding. Such bleedings are independent predictors of long-term adverse clinical events. Data that are currently available on the magnitude and the predictors of bleeding complications in patients with ACS have been obtained from randomized clinical trials. However, patients perceived to be at higher risk of complications, including the elderly or those with renal insufficiency, are often excluded from these trials, but constitute a significant percentage of patients treated for ACS. For these reasons, new bleeding risk scores are under evaluation to facilitate management and subsequent treatment decisions in the real world. Better identification of higher risk patients, careful dosing and appropriate monitoring of antithrombotic therapies, and incorporation of various peri-procedural strategies in routine clinical practice may potentially reduce the risk of bleeding of patients with ACS and further improve their clinical outcomes.