Factors Associated With Rebleeding and Early Mortality Following Transcatheter Arterial Embolization for Spontaneous Muscle Hematoma: A Single-Center Experience Including the Period of the Coronavirus Disease Pandemic.

Objectives We aim to investigate factors associated with rebleeding and mortality within one month of transcatheter arterial embolization (TAE) for spontaneous muscle hematoma (SMH) and the impact of the novel coronavirus disease 2019 (COVID-19). Methods This retrospective analysis included 33 patients who underwent TAE for SMH at a single center between 2012 and 2022. After 2020, eight of these patients had the COVID-19 infection. Patient characteristics, laboratory findings, embolic materials, and imaging findings were compared between the rebleeding and non-rebleeding groups, as well as between the early mortality and survival groups. Results Among all patients, 72.7% were on anticoagulant therapy before the onset of SMH. Of these, 27.2% required retreatment due to rebleeding. Patients who experienced rebleeding were more likely to have a platelet count below 50,000/µL, fibrinogen levels below 150 mg/dL, and an activated partial thromboplastin time (APTT) ratio above 2.5. Patients with SMH unrelated to anticoagulants had a higher rebleeding rate (56%), which may serve as a predictor of rebleeding. No significant difference in rebleeding rates was observed between patients with and without COVID-19 infection. Early mortality within one month of onset occurred in 24.2% of patients, with a higher prevalence among those with a history of malignancy. However, there was no increase in early mortality among patients who required retreatment for rebleeding. Conclusions Patients with a low platelet count, fibrinogen level, prolonged APTT, and non-anticoagulant-related SMH are at a high risk of rebleeding and require close monitoring. Severe comorbidities, including malignancies and COVID-19, can affect mortality rates. TAE remained effective even in cases of rebleeding. Advances in knowledge This study indicated non-anticoagulant-related SMH and hematological parameters as factors associated with rebleeding.