C52-34 Spontaneous Coracobrachialis Hematoma During Transcatheter Aortic Valve Replacement Hospitalization in a Patient With EndStage Renal Disease on Apixaban

Abstract Introduction Spontaneous intramuscular hematoma (SMH) is an uncommon but clinically significant complication, most frequently observed in patients exposed to antithrombotic agents and those with advanced age or comorbidities. While lower limb and retroperitoneal hematomas predominate, upper limb involvement is rare, and isolated coracobrachialis hematoma has not been previously described. Bleeding events after transcatheter aortic valve replacement (TAVR) remain a major source of morbidity, particularly in patients with end-stage renal disease (ESRD) and chronic anticoagulation. Accordingly, The present case highlights the intersection of anticoagulation, renal dysfunction, and procedural stress in the pathogenesis of SMH. Case Description A 64-year-old man with ESRD on hemodialysis, chronic atrial fibrillation managed with apixaban (dose), severe coronary artery disease, and aortic stenosis was admitted for TAVR and coronary angioplasty. Recovery was complicated by pneumonia, cardiac arrest, and hypoactive delirium. In the course, he developed progressive right upper extremity edema. Right upper extremity venous duplex excluded deep venous thrombosis but revealed an echogenic non-vascular axillary mass. CT showed mild subcutaneous fat stranding; MRI demonstrated a 4.4 × 4.0 × 6.2 cm lesion adjacent to the coracobrachialis muscle with heterogeneous T1 and predominantly low T2 signal, consistent with subacute hematoma. Laboratory revealed down trending hemoglobin without obvious signs of bleeding. Apixaban was withheld and renally dosed low-molecular-weight heparin initiated for greater control over anticoagulation intensity and reversibility. Interventional radiology and surgery were consulted; conservative management was chosen due to hemodynamic stability and absence of compartment syndrome. Serial imaging showed no expansion of the hematoma. Discussion Major muscular hematomas in anticoagulated patients are associated with substantial morbidity and in-hospital mortality, particularly in advanced age and hematoma size 5.5 cm as independent predictors of poor outcome. Bleeding rates after TAVR remain high in patients with significant comorbidities, and tailored antithrombotic regimens are recommended to mitigate risk. Imaging modalities such as CT and MRI are essential for accurate localization and characterization of hemorrhagic lesions associated with anticoagulant therapy especially in the context of an infectious process. In patients with end-stage renal disease, microvascular fragility and uremic coagulopathy further amplify bleeding risk, and individualized management is essential. The novelty of this case lies in the rare anatomical site and the complex interplay of risk factors, underscoring the need for vigilance, multimodal imaging, and individualized management in high-risk populations for urgent detection. Conservative management is appropriate for stable patients, but surgical or endovascular intervention may be required for hemodynamic instability or compartment syndrome. Figure 1: 4.49cm x 2.1cm RA mass shown on TEE This abstract is funded by: None