SESSION TITLE: Rare Cases in Cardiothoracic SurgerySESSION TYPE: Rapid Fire Case ReportsPRESENTED ON: 10/18/2022 12:25 pm - 01:25 pmINTRODUCTION: Internal carotid artery pseudoaneurysms are rare and potentially lethal, commonly associated with a history of blunt/penetrating trauma, infection and vasculitis, less commonly with auto-immune or unrecognized etiologies.CASE PRESENTATION: 39-year-old female with past medical history of multiple miscarriages who presented with sore throat, dysphagia, hoarseness, and left neck swelling for 3 weeks. Prior to hospitalization, she was initially treated with multiple antibiotics for parotitis by her primary care physician. She denied any history of trauma or motor vehicle collision. On physical examination, a large mass on the left neck with audible bruit was present. CTA soft tissue neck and CTA Brain & Neck were consistent with extracranial left internal carotid artery (2.6 x 2.5 x 3.1 cm) and right distal internal carotid artery (9.3 mm x 3.4 cm) pseudoaneurysms, with multifocal aneurysmal dilatation of the right vertebral artery. Further auto-immune and hypercoagulable workup were undertaken due to her history of miscarriages, including antineutrophil cytoplasmic antibodies panel, connective tissue cascade, proteinase 3, and myeloperoxidase studies—all of which were all negative. She subsequently underwent combination of precise stent and pipeline flow diversion stents augmented by coil embolization in the left internal carotid artery, complicated by left groin hematoma due to increased friability of blood vessels. Due to complaints of continued hoarseness, flexible laryngoscopy demonstrated paretic left vocal cord, likely secondary to recurrent laryngeal nerve stretch injury. At the two week follow up appointment, she endorsed significant reduction in the size of her neck mass, with fluctuating hoarseness.DISCUSSION: Bilateral carotid artery pseudoaneurysm without a known etiology are increasingly rare. Oftentimes, patients present with neurological deficits such as cranial nerve damage and hemorrhage, which were not present in our patient. The presence of multiple pseudo-aneurysms, combined with increased friability of blood vessels, raises concern for vasculitis, including Takayusu's disease, Polyarteritis Nodosa, Kawasaki disease, and Behcet's disease. However, the absence of systemic symptoms could point to connective tissue disorders such as Ehler Danlos/Loeys Dietz syndromes. Stent placement remains first line in management, with early onset complications including arterial dissection and embolic strokes. Additionally, late onset complications include graft occlusion/recanalization.CONCLUSIONS: The rapid onset of symptoms, combined with early misdiagnosis of parotitis, led to a potential delay in diagnosis and development of further sequelae, including vocal cord dysfunction. Early recognition of symptoms, such as pulsatile neck mass, remains key, given proclivity for rupture (91% of reported pseudo-aneurysms) and guarded prognosis/risk for recurrence.Reference #1: Pearson SE, Choi SS. Pseudoaneurysm of the internal carotid artery: a case report and review of the literature. Archives of Otolaryngology–Head & Neck Surgery. 2005;131(5):454-456. doi:10.1001/archotol.131.5.454Reference #2: Endovascular management of internal carotid artery pseudoaneurysms: Retrospective observational study. Interdisciplinary Neurosurgery. 2021;24:101042. doi:10.1016/j.inat.2020.101042DISCLOSURES: No relevant relationships by Nina AmilineniNo relevant relationships by Jeel GalaNo relevant relationships by Amogh Nadkarni SESSION TITLE: Rare Cases in Cardiothoracic Surgery SESSION TYPE: Rapid Fire Case Reports PRESENTED ON: 10/18/2022 12:25 pm - 01:25 pm INTRODUCTION: Internal carotid artery pseudoaneurysms are rare and potentially lethal, commonly associated with a history of blunt/penetrating trauma, infection and vasculitis, less commonly with auto-immune or unrecognized etiologies. CASE PRESENTATION: 39-year-old female with past medical history of multiple miscarriages who presented with sore throat, dysphagia, hoarseness, and left neck swelling for 3 weeks. Prior to hospitalization, she was initially treated with multiple antibiotics for parotitis by her primary care physician. She denied any history of trauma or motor vehicle collision. On physical examination, a large mass on the left neck with audible bruit was present. CTA soft tissue neck and CTA Brain & Neck were consistent with extracranial left internal carotid artery (2.6 x 2.5 x 3.1 cm) and right distal internal carotid artery (9.3 mm x 3.4 cm) pseudoaneurysms, with multifocal aneurysmal dilatation of the right vertebral artery. Further auto-immune and hypercoagulable workup were undertaken due to her history of miscarriages, including antineutrophil cytoplasmic antibodies panel, connective tissue cascade, proteinase 3, and myeloperoxidase studies—all of which were all negative. She subsequently underwent combination of precise stent and pipeline flow diversion stents augmented by coil embolization in the left internal carotid artery, complicated by left groin hematoma due to increased friability of blood vessels. Due to complaints of continued hoarseness, flexible laryngoscopy demonstrated paretic left vocal cord, likely secondary to recurrent laryngeal nerve stretch injury. At the two week follow up appointment, she endorsed significant reduction in the size of her neck mass, with fluctuating hoarseness. DISCUSSION: Bilateral carotid artery pseudoaneurysm without a known etiology are increasingly rare. Oftentimes, patients present with neurological deficits such as cranial nerve damage and hemorrhage, which were not present in our patient. The presence of multiple pseudo-aneurysms, combined with increased friability of blood vessels, raises concern for vasculitis, including Takayusu's disease, Polyarteritis Nodosa, Kawasaki disease, and Behcet's disease. However, the absence of systemic symptoms could point to connective tissue disorders such as Ehler Danlos/Loeys Dietz syndromes. Stent placement remains first line in management, with early onset complications including arterial dissection and embolic strokes. Additionally, late onset complications include graft occlusion/recanalization. CONCLUSIONS: The rapid onset of symptoms, combined with early misdiagnosis of parotitis, led to a potential delay in diagnosis and development of further sequelae, including vocal cord dysfunction. Early recognition of symptoms, such as pulsatile neck mass, remains key, given proclivity for rupture (91% of reported pseudo-aneurysms) and guarded prognosis/risk for recurrence. Reference #1: Pearson SE, Choi SS. Pseudoaneurysm of the internal carotid artery: a case report and review of the literature. Archives of Otolaryngology–Head & Neck Surgery. 2005;131(5):454-456. doi:10.1001/archotol.131.5.454 Reference #2: Endovascular management of internal carotid artery pseudoaneurysms: Retrospective observational study. Interdisciplinary Neurosurgery. 2021;24:101042. doi:10.1016/j.inat.2020.101042 DISCLOSURES: No relevant relationships by Nina Amilineni No relevant relationships by Jeel Gala No relevant relationships by Amogh Nadkarni