BACKGROUND: Andexanet alfa, an anti-Xa inhibitor antagonist, induces heparin resistance. Here, we report a case of successful management of cardiopulmonary bypass with andexanet alfa-induced heparin resistance using nafamostat mesylate.
METHODS: An 84-year-old female, with Stanford type A acute aortic dissection, underwent an emergency surgery for total aortic arch replacement. Andexanet alfa 400 mg was administered preoperatively to antagonize edoxaban, an oral Xa inhibitor. Heparin 300 IU/kg was administered before cardiopulmonary bypass, and the activated clotting time (ACT) was 291 s. The ACT was 361 s after another administration of heparin 200 IU/kg. According to our routine therapy for heparin resistance, an initial dose of nafamostat mesylate 10 mg was administered intravenously, followed by a continuous infusion of 20-30 mg/h. The ACT was prolonged to 500 s, and cardiopulmonary bypass was successfully established thereafter.
CONCLUSIONS: This case report presents the successful management of cardiopulmonary bypass with andexanet alfa-induced heparin resistance using nafamostat mesilate. This report presents the successful management of cardiopulmonary bypass with andexanet alfa-induced heparin resistance using nafamostat mesilate.

A rare case of a 35 years old woman presented with renal arcuate vein thrombosis (RAVT) and acute kidney injury (AKI) following upper respiratory tract symptoms and toxic substance ingestion. Histopathological evaluation of the patient\'s kidney tissue indicated a rare venous thrombosis in the renal arcuate veins. Anticoagulation with Apixaban, a direct oral anticoagulant (DOAC), was commenced, and the patient\'s symptoms resolved during the hospital stay. Hitherto, a limited number of studies have shown the concurrent presentation of RAVT and overt AKI in patients following ingestion of nephrotoxic agents. Further studies are necessary to elucidate the etiology, clinical presentation, and treatment of RAVT. We suggest that Apixaban be studied as a suitable alternative to conventionally used anti-coagulants such as Warfarin in patients who lack access to optimal health care facilities.

Renal vein thrombosis (RVT) is a rare condition characterized by the formation of a blood clot in one or both of the renal veins. Bilateral involvement is more common, but when the condition affects only one side, it usually occurs on the left due to more extensive venous vasculature compared to the right side. RVT can be caused by various factors such as trauma, dehydration, malignancy, and a hypercoagulable state. Acute RVT is typically more severe than chronic, and it can cause symptoms such as renal infarction, acute kidney injury, renal failure, severe flank pain, and hematuria. Some cases of RVT have also been linked to coronavirus disease 2019 (COVID-19), which is widely recognized to induce a hypercoagulable state. The standard treatment for RVT is warfarin but in this case report, we describe a COVID-19 patient with RVT whose thrombus was successfully treated with direct-acting oral anticoagulant (DOAC) apixaban for six months.

Atrial fibrillation (AF) is a risk factor for brain infarction, which can lead to epilepsy. We aimed to investigate whether treatment of AF with direct oral anticoagulants (DOACs) affects the risk of epilepsy in comparison to treatment with the vitamin K antagonist phenprocoumon (PPC).
We performed an active comparator, nested case-control study based on the German Pharmacoepidemiological Research Database that includes claims data from statutory health insurance providers of about 25 million persons since 2004. In 2011-17, 227 707 AF patients initiated treatment with a DOAC or PPC, of which 1828 cases developed epilepsy on current treatment with an oral anticoagulant. They were matched to 19 084 controls without epilepsy. Patients with DOAC treatment for AF had an overall higher risk of epilepsy with an odds ratio of 1.39, 95% CI (1.24; 1.55) compared to current PPC treatment. Cases had higher baseline CHA2DS2-VASc scores and more frequently a history of stroke than controls. After excluding patients with ischaemic stroke prior to the diagnosis of epilepsy, the risk of epilepsy was still higher on DOACs than on PPC. In contrast, within a cohort of patients with venous thromboembolism, the risk of epilepsy on treatment with DOACs was less elevated [adjusted odds ratio 1.15, 95% CI (0.98; 1.34)].
In patients with AF initiating oral anticoagulation, treatment with a DOAC was associated with an increased risk of epilepsy compared to the vitamin K antagonist PPC. Covert brain infarction may explain the observed elevated risk of epilepsy.

Objective-Direct oral anticoagulants (DOAC) are replacing vitamin K antagonists (VKA) for the prevention of ischemic stroke and venous thromboembolism. We set out to assess the effect of prior treatment with DOAC and VKA in patients with aneurysmal subarachnoid hemorrhage (SAH). Methods-Consecutive SAH patients treated at two (Aachen, Germany and Helsinki, Finland) university hospitals were considered for inclusion. To assess the association between anticoagulant treatments on SAH severity measure by modified Fisher grading (mFisher) and outcome as measured by the Glasgow outcome scale (GOS, 6 months), DOAC- and VKA-treated patients were compared against age- and sex-matched SAH controls without anticoagulants. Results-During the inclusion timeframes, 964 SAH patients were treated in both centers. At the time point of aneurysm rupture, nine patients (0.93%) were on DOAC treatment, and 15 (1.6%) patients were on VKA. These were matched to 34 and 55 SAH age- and sex-matched controls, re-spectively. Overall, 55.6% of DOAC-treated patients suffered poor-grade (WFNS4-5) SAH compared to 38.2% among their respective controls (p = 0.35); 53.3% of patients on VKA suffered poor-grade SAH compared to 36.4% in their respective controls (p = 0.23). Neither treatment with DOAC (aOR 2.70, 95%CI 0.30 to 24.23; p = 0.38), nor VKA (aOR 2.78, 95%CI 0.63 to 12.23; p = 0.18) were inde-pendently associated with unfavorable outcome (GOS1-3) after 12 months. Conclusions-Iatrogenic coagulopathy caused by DOAC or VKA was not associated with more severe radiological or clinical subarachnoid hemorrhage or worse clinical outcome in hospitalized SAH patients.

Left ventricular thrombus is a known complication following acute myocardial infarction that can lead to systemic thromboembolism. To obviate the risk of thromboembolism, the patient needs anticoagulation in addition to dual antiplatelet therapy. However, combining antiplatelets with anticoagulants substantially increases the bleeding risk. Traditionally, vitamin K antagonists (VKAs) have been the sheet anchor for anticoagulation in this scenario. The use of direct oral anticoagulants has significantly attenuated the bleeding risk associated with anticoagulation for atrial fibrillation and venous thromboembolism. Furthermore, in patients with atrial fibrillation undergoing percutaneous coronary intervention, the use of direct oral anticoagulants (DOACs) in conjunction with antiplatelets has been found to be noninferior in reducing ischemic events while significantly attenuating the bleeding compared with VKA. After initial case reports, multiple observational and nonrandomized studies have now safely and effectively utilized direct oral anticoagulants for anticoagulation in left ventricular thrombus. Here, we report a series of two cases presenting with left ventricular thrombus following acute myocardial infarction. In this case series, we try to address the issues concerning the choice and duration of anticoagulation in the case of postinfarct left ventricular thrombus. Pending the results of large randomized control trials, the judicious use of direct oral anticoagulant is warranted when taking into consideration the ischemic and bleeding profile in an individualized approach.

A left ventricular (LV) thrombus is a relatively common and well-known condition associated with significant LV systolic dysfunction. However, LV thrombosis is unusual in the absence of kinetic abnormalities. The elderly gentleman presented with subacute onset of bilateral lower limb discomfort and cold extremities, but no gangrene. With normal LV function, an echocardiogram revealed a massive movable LV apical clot. He was treated with dual antiplatelets and heparin at first. He switched to dabigatran 110 mg twice a day in combination with dual antiplatelets. The thrombus had entirely vanished and leg problems had improved after a 2-week follow-up. For the next six months, he was treated with aspirin and dabigatran and was asymptomatic at follow-up. There are no specific guidelines for treating an intracardiac thrombus. Experts agree that a hypermobile and pedunculated LV thrombus with a high embolic risk should be surgically removed as soon as possible. According to ESC/ACC guidelines, all patients with LV thrombus associated with myocardial infarction should be treated with anticoagulation. Warfarin requires regular International Normalized Ratio (INR) monitoring and has a small therapeutic window; hence a direct oral anticoagulant (DOAC) could be a viable therapeutic solution. However, there are no guideline recommendations to date to guide DOAC therapy for this indication.

BACKGROUND: Adrenal hemorrhage (AH) is a rare condition that can result in a life-threatening medical emergency. This medical condition could be caused by several underlying factors, one of which is the use of anticoagulants. As far as we are aware, direct oral anticoagulant (DOAC) agents are a rare but possible cause of AH.
METHODS: Herein, we described two cases of AH due to DOACs. The first case was a 35-year-old Iranian woman with a past medical history of Hashimoto thyroiditis who was being treated with apixaban due to the previous thrombosis. Her first symptoms of AH (November 2021) were strangely similar to symptoms of autoimmune Addison disease (AAD) which led to a confirmed diagnosis of autoimmune polyendocrine syndrome type 2 (APS-2). An abdominal MRI revealed an oval shape well-encapsulated cystic mass with a diameter of 20 × 14 mm with a thick and low signal intensity rim in the left adrenal gland, highly suggestive of sub-acute left-sided AH. Our second case was an 89-year-old Iranian woman who had been admitted to the hospital (August 2021) with low blood pressure and disorientation. At the beginning of her admission, the evaluation showed hyponatremia, and further evaluations confirmed adrenal insufficiency (AI). The patient reported rivaroxaban usage for deep vein thrombosis prophylaxis after femur fixation surgery. Her abdominal CT scans showed bilateral adrenal masses highly suggestive of AH. Her follow-up examination showed persistent AI after three months.
CONCLUSIONS: Given the history of our cases, physicians should be aware of AH in patients receiving DOACs, particularly in elderly patients who are at high risk of bleeding. It is also worth noting that AH can occur in any patient with any medical history and history of DOAC use, which is why patients must be closely monitored.

BACKGROUND: Direct oral anticoagulants (DOACs) carry a lower potential risk of food/herb and drug interactions compared with oral vitamin K antagonists. However, as a new class of medications, drug interactions of DOACs have not been fully known.
METHODS: We herein present the case of a 64-year old male with the complaint of acute onset epistaxis and bleeding gums following the concomitant use of rivaroxaban and saffron supplement. It seems that coadministration of DOACs and saffron supplements should be avoided due to the potential drug-herbal interactions and possible risk of subsequent bleeding complications.
CONCLUSIONS: However, further larger scale surveillance studies are needed to confirm the findings and assess the clinical significance.

Purpose: Direct oral anticoagulants (DOACs) pose a challenge when given with potent CYP3A4 and P-gp inhibitors, such as the commonly prescribed pharmacokinetic booster ritonavir. As per the manufacturer, apixaban offers a dose reduction when administered concurrently with ritonavir; thus, we explore the clinical indication and safety of apixaban when given with ritonavir-boosted highly active antiretroviral therapy (HAART) in an HIV patient. Summary: We describe a 73-year-old male with extensive cardiac history, including a past medical history of resolved left ventricular thrombus, newly diagnosed non-valvular atrial fibrillation treated with warfarin, and HIV infection treated with ritonavir-boosted HAART. The patient presented to the emergency department with bleeding from multiple sites, necessitating the use of vitamin K. Consequently, his hospital course was complicated by episodes of minor bleeding and labile INR. Due to the complicated nature of his condition and the potential for drug-drug interactions (DDIs), he was transitioned from warfarin to apixaban. Since there is little readily available data to support the use of rivaroxaban and dabigatran with ritonavir, our patient was safely started on dose-reduced apixaban for stroke prophylaxis in atrial fibrillation due to the predictable nature of apixaban pharmacokinetics and proven superiority regarding adverse effects, as compared to other DOACs. Conclusion: Dose-reduced apixaban is a safe and viable choice in patients with atrial fibrillation warranting stroke prophylaxis while concurrently receiving ritonavir-boosted HAART.