Antithrombotic Management in Adult Kidney Transplantation – A European survey study

In kidney transplantation (KTx), renal graft thrombosis (RGT) is one of the main reasons for early graft loss. Although evidence-based guidance on prevention of RGT is lacking, thromboprophylaxis is widely used. The aim of this survey was to obtain a European view of the different thromboprophylactic strategies applied in KTx. An online 22-question survey, addressed to KTx professionals, was distributed by e-mail and via platforms of the European Society for Organ Transplantation. Seventy-five responses (21 countries, 51 centers) were received: 75% had over 10 years’ clinical experience, 64% were surgeons, 29% nephrologists and 4% urologists. A written antithrombotic management protocol was available in 75% of centers. In 8 (16%) of centers respondents contradicted each other regarding the availability of a written protocol. Thromboprophylaxis is preferred by 78% of respondents, independent of existing antithrombotic management protocols. Ninety-two percent of respondents indicated that an anticipated bleeding risk is the main reason to discontinue chronic antithrombotic therapy preoperatively. Intraoperatively, 32% of respondents administer unfractionated heparin (400 – 10.000 international units with a median of 5000) in selected cases. Despite an overall preference for perioperative thromboprophylaxis in KTx, there is a high variation within Europe regarding type, timing and dosage, most likely due to the paucity of high-quality studies. Further research is warranted in order to develop better guidelines.

Safety and efficacy of prophylactic tirofiban infusion for acute intracranial intraprocedural stent thrombosis

Periprocedural antithrombotic management with glycoprotein IIb/IIIa inhibitors (GPI) for intracranial artery stenting is still controversial. We sought to assess the safety and efficacy of prophylactic tirofiban infusion for acute intracranial intraprocedural stent thrombosis in routine clinical practice. From January 2013 to December 2019, consecutive patients treated with endovascular stenting for symptomatic intracranial atherosclerotic stenosis (ICAS) were identified and dichotomized by whether tirofiban was used. The efficacy and safety outcomes were compared by propensity score matching. A total of 160 consecutive patients in the tirofiban group and 177 patients in the non-tirofiban group were enrolled. Propensity score matching analysis selected 236 matched patients. One acute intraprocedural stent thrombosis (AIST) occurred in patients receiving prophylactic tirofiban, while 8 in the non-tirofiban group. The incidence of AIST in the tirofiban group was significantly lower than that in the non-tirofiban group (0.8% vs 6.8%, P = 0.039). The periprocedural ischemic events (8.5% vs 5.1%, P = 0.424), periprocedural intracranial hemorrhage (4.2% vs 0.8%, P = 0.219) and 30-day total mortality (3.4% vs 0%, P = 0.125) were not statistically different between the two groups. Compared with conventional stenting angioplasty without tirofiban, tirofiban prophylactic infusion can lower the incidence of AIST, without increasing the risk of periprocedural intracranial hemorrhage and 30-day total mortality. However, there is no superiority in reducing periprocedural ischemic events. The current study adds more important insights to the available clinical evidence on the use of tirofiban during stenting of ICAS.

New Trends and Advances in Non-Variceal Gastrointestinal Bleeding—Series II

The gastrointestinal tract is a long tubular structure wherein any point in the mucosa along its entire length could be the source of a hemorrhage. Upper (esophagel and gastroduodenal) and lower (jejunum, ileum, and colon) gastrointestinal bleeding are common. Gastroduodenal and colonic bleeding are more frequent than bleeding from the small bowel, but nowadays the entire gastrointestinal tract can be explored endoscopically and bleeding lesions can be locally treated successfully to stop or prevent further bleeding. The extensive use of antiplatelet and anticoagulants drugs in cardiovascular patients is, at least in part, the cause of the increasing number of patients suffering from gastrointestinal bleeding. Patients with these conditions are usually older and more fragile because of their comorbidities. The correct management of antithrombotic drugs in cases of gastrointestinal bleeding is essential for a successful outcome for patients. The influence of the microbiome in the pathogenesis of small bowel bleeding is an example of the new data that are emerging as potential therapeutic target for bleeding prevention. This text summarizes the latest research and advances in all forms of acute gastrointestinal bleeding (i.e., upper, small bowel and lower). Diagnosis is approached, and medical, endoscopic or antithrombotic management are discussed in the text in an accessible and comprehensible way.

Recurrent embolisms despite adequate anticoagulant therapy in a patient with prosthetic heart valves and atrial fibrillation: a case report

Background Antithrombotic management in patients with atrial fibrillation (AF) that have undergone heart valve surgery may be challenging, especially in the context of thromboembolic events during follow-up. The combination of pharmacological therapies with modern transcatheter interventions allows these more complex cases to be overcome. Case summary We present the case of a 66-year-old female with a history of AF and mechanical aortic and mitral valve replacement, which was admitted to the hospital complaining of dizziness and unsteady gait. A computerized tomography scan of the brain confirmed the diagnosis of embolic stroke. Two years later, the patient complained of sudden onset of chest pain, accompanied by electrocardiographic abnormalities and elevated high-sensitivity troponin T. Emergency cardiac catheterization revealed embolic myocardial infarction with distal occlusion of the obtuse marginal artery. Again, 2 years later, the patient suffered a new cerebral embolic event. Given the adequate anticoagulation therapy throughout almost the entire clinical course, percutaneous left atrial appendage closure was proposed as an adjunct to vitamin K antagonist treatment. Notably, intraprocedural transoesophageal echocardiography revealed the presence of a previously undetected left atrial appendage thrombus, thus an embolic protection device was used during the procedure, which was successfully carried out without complications. Discussion This case report demonstrates the complexity of the antithrombotic management in patients with AF and prosthetic heart valves, and highlights the importance of an individualized approach, integrating new therapeutic strategies to achieve success, in patients that present thromboembolic events despite adequate anticoagulation therapy.

Antithrombotic Management for Atrial Fibrillation Patients Undergoing Percutaneous Coronary Intervention or With Acute Coronary Syndrome: An Evidence-Based Update

Combined antithrombotic regimens for atrial fibrillation (AF) patients with coronary artery disease, particularly for those who have acute coronary syndrome (ACS) and/or are undergoing percutaneous coronary intervention (PCI), presents a great challenge in the real-world clinical scenario. Conventionally, a triple antithrombotic therapy (TAT), which consists of combined oral anticoagulant therapy to prevent systemic embolism or stroke along with dual antiplatelet therapy to prevent coronary arterial thrombosis (CAT), is used. However, TAT has been associated with a significantly increased risk of bleeding. With the emergence of non-vitamin K antagonist oral anticoagulants (NOACs), randomized controlled trials have demonstrated a better risk-to-benefit ratio of dual antithrombotic therapy (DAT) in combination of a NOAC and with a P2Y12 inhibitor than vitamin K antagonist-based TAT. The results of these studies have impacted the recommendations of current international guidelines, which favor a DAT with a NOAC and P2Y12 inhibitor (especially clopidogrel) in this clinical setting. Additionally, aspirin can be administered during the periprocedural period, while the treatment duration of TAT should be as short as possible. In this article, we summarize the up-to-date evidence regarding antithrombotic regimens for AF patients with PCI or ACS, with a specific focus on the optimal approach and critical discussions of key scientific data and future developments for antithrombotic management in these patients.