PO114 | A CASE OF ACQUIRED HEMOPHILIA AFTER TAVI AND CORONARY ANGIOPLASTY IN PATIENT WITH ATRIAL FIBRILLATION AND MULTIPLES CARDIOVASCULAR RISK FACTORS – THE ART AND SCIENCE OF THERAPEUTIC CONFLICT

M.M. Poggi¹, C. Tamburini², M. Littera², M. Mazzetti² | ¹SOC Medicina 1, Nuovo Ospedale Prato, Prato, Italy; ²SOD Medicina Interna Interdisciplinare, Azienda Ospedaliera Universitaria Careggi, Firenze, Italy

Background. Acquired hemophilia A (AHA) is a rare autoimmune disorder characterized by inhibitory autoantibodies against FVIII. Half of cases are associated with autoimmune diseases, cancer, infections, drugs, or pregnancy. Symptoms usually include subcutaneous and intramuscular bleeds, unlike congenital hemophilia which affects mainly the joints. Diagnosis is made by prolonged aPTT not correcting on a mixing test, along with reduced FVIII activity and the presence of inhibitors. Treatment aims to control bleeding and eradicate the inhibitor. Hemostatic therapy includes bypassing agents (rFVIIa or aPCC) or rpFVIII. In recent years, Emicizumab, a bispecific monoclonal antibody that mimics FVIII’s action bridging FIXa and FXa, has emerged as a novel off-label therapeutic option. Steroids, Rituximab, or Cyclophosphamide, are used to suppress autoantibody production.
Case report. We present the case of a 83 years old female patient with acquired A haemophilia diagnosed after TAVI and coronary angioplasty. Clinical history included multiple cardiovascular risk factors, including CAD and LEAD previously treated with revascularization. In December 2025, the patient presented to ED with an episode of HF secondary to newly diagnosed AF with echocardiographic evidence of severe aortic stenosis. A coronary angiography showed significant CAD progression on the circumflex and the right coronary arteries, so the patient was transferred to the Cardiology Department where she underwent TAVI and revascularization on the culprit arteries. A triple antithrombotic therapy (TAT) with aspirin, clopidogrel, and DOAC (rivaroxaban) was started. Pre-procedural coagulation test showed a spontaneous aPTT prolungation (72 ms). After the procedure, the patient began to present spontaneous hematomas in the upper limbs. Coagulation factor assays revealed a FVIII deficiency (4%) along with positivity of FVIII inhibitor at high titer (52.90 U/mL), confirming the diagnosis of AHA. TAT was withheld and treatment with prednisone 1 mg/Kg, cyclophosphamide 1 mg/Kg, and emicizumab (LD 6 mg/Kg on the 1st day and 3 mg/Kg on the 2nd day, MD 1.5 mg/Kg weekly) was started. After normalization of the aPTT and FVIII activity, aspirin was resumed and, after 1 week, DAPT with clopidogrel was restarted. Screening for infectious (HBV, HCV, HIV, Parvovirus B19, EBV, CMV) and autoimmune (ANA, ENA, RF, CCP, LA, aβ2GPI, aCL) causes was negative. Contrast-enhanced whole-body CT scan, 18F-FDG-PET and thyroid US excluded lesions suspicious for cancer. For progressive thrombocytopenia (nadir: 66,000/mm3) likely secondary to cytotoxic therapy, and good laboratory response with FVIII activity ​​persistently in range, it was decided to maintain Clopidogrel exclusively, and the patient was discharged with an appointment at our Bleeding Disorders Center for further follow-up. Unfortunately, 3 weeks later, the patient died of unknown causes.
Conclusions. AHA is a rare but potentially life-threatening disorder, especially if under-recognized and treated late. Since it’s more common in older adults who currently have multiple cardiovascular diseases requiring antithrombotic medications, treatment decisions are extremely challenging, bordering between art and science. A personalized approach is essential to modulate the intensity of antithrombotic therapy and bleeding prophylaxis in this patient population, even though outcomes can often be unfavorable.