Anterior clinoidectomy in low lying internal carotid artery-posterior communicating artery aneurysm.

BACKGROUND: At times, a regulation internal carotid artery-posterior communicating artery junction (ICA-P-Comm) aneurysm becomes a surgical hurdle owing to its close proximity to the anterior clinoid process, an immovable ICA and a concealed dominant P-Comm artery arising from the aneurysm neck. METHOD: A 70 year old patient with a low lying ICA-P-Comm aneurysm underwent a "tailored" intradural clinoidectomy for aneurysm clipping. CONCLUSION: A tailored anterior clinoidectomy to expose "just enough" allows a proximal ICA control in a suitable area, mobility of an atherosclerotic ICA and exposes the P-Comm artery origin which are essential in safe clipping of these aneurysms.

Management of Incidental Carotid Cave Aneurysm.

BACKGROUND: Incidental diagnosis of saccular aneurysms is more common with the advent of imaging techniques. Because of the severe morbidity and mortality that they can cause, treatment is chased for them, either microsurgical treatment or endovascular, even when they are diagnosed incidentally. Carotid cave aneurysms are rare, and they seem to have a more benign course compared to other intracranial aneurysms, probably related to the physical enveloping effect of the surrounding structures. Yet, their microsurgical treatment is a serious challenge technically for the neurosurgeon, with its severe morbidity and mortality for the patient. Endovascular techniques have their risks, too. PURPOSE: In this paper, we analyzed and presented our series of incidentally diagnosed carotid cave aneurysms. MATERIALS AND METHODS: The age, gender of patients, the size, laterality, and MR angiographic follow-up of aneurysms were reported. Their clinical results were noted. RESULTS: Fifty-six patients who had incidentally been diagnosed with 59 carotid cave aneurysms were followed up. No patient was microsurgically treated, but 15 patients had endovascular treatment for 15 aneurysms. The mean size of 15 treated aneurysms was 4.6 ± 2.1 (range = 2-10) mm, and it was 3.0 ± 1.5 (range = 1.7-10) mm for the untreated aneurysms (n = 44). There was no significant difference between the follow-up times of the treated and untreated groups (P = 0.487). The median follow-up of 59 aneurysms in 56 patients was 52 (mean = 49.6 ± 27.9, range = 1-124) months, with a total follow-up of 244 aneurysm years. None of the patients had subarachnoid hemorrhage related to carotid cave aneurysms during follow-up, and none of the aneurysms had shown growth. Two patients who had endovascular treatment had ischemic complications with minor neurologic deficits. CONCLUSION: Follow-up can be a reasonable option for the incidental aneurysms that are located and confined to the carotid cave. Additionally, TOF might be a reliable method for follow-up imaging of carotid cave aneurysms.

Atherosclerotic Plaque Epigenetic Age Acceleration Predicts a Poor Prognosis and Is Associated With Endothelial-to-Mesenchymal Transition in Humans.

BACKGROUND: Epigenetic age estimators (clocks) are predictive of human mortality risk. However, it is not yet known whether the epigenetic age of atherosclerotic plaques is predictive for the risk of cardiovascular events. METHODS: Whole-genome DNA methylation of human carotid atherosclerotic plaques (n=485) and of blood (n=93) from the Athero-Express endarterectomy cohort was used to calculate epigenetic age acceleration (EAA). EAA was linked to clinical characteristics, plaque histology, and future cardiovascular events (n=136). We studied whole-genome DNA methylation and bulk and single-cell transcriptomics to uncover molecular mechanisms of plaque EAA. We experimentally confirmed our in silico findings using in vitro experiments in primary human coronary endothelial cells. RESULTS: Male and female patients with severe atherosclerosis had a median chronological age of 69 years. The median epigenetic age was 65 years in females (median EAA, -2.2 [interquartile range, -4.3 to 2.2] years) and 68 years in males (median EAA, -0.3 [interquartile range, -2.9 to 3.8] years). Patients with diabetes and a high body mass index had higher plaque EAA. Increased EAA of plaque predicted future events in a 3-year follow-up in a Cox regression model (univariate hazard ratio, 1.7; P=0.0034) and adjusted multivariate model (hazard ratio, 1.56; P=0.02). Plaque EAA predicted outcome independent of blood EAA (hazard ratio, 1.3; P=0.018) and of plaque hemorrhage (hazard ratio, 1.7; P=0.02). Single-cell RNA sequencing in plaque samples from 46 patients in the same cohort revealed smooth muscle and endothelial cells as important cell types in plaque EAA. Endothelial-to-mesenchymal transition was associated with EAA, which was experimentally confirmed by TGFß-triggered endothelial-to-mesenchymal transition inducing rapid epigenetic aging in coronary endothelial cells. CONCLUSIONS: Plaque EAA is a strong and independent marker of poor outcome in patients with severe atherosclerosis. Plaque EAA was linked to mesenchymal endothelial and smooth muscle cells. Endothelial-to-mesenchymal transition was associated with EAA, which was experimentally validated. Epigenetic aging mechanisms may provide new targets for treatments that reduce atherosclerosis complications.

Learning curve of transfemoral carotid artery stenting in the Vascular Quality Initiative registry.

OBJECTIVE: With the recent expansion of the Centers for Medicare and Medicaid Services coverage, transfemoral carotid artery stenting (tfCAS) is expected to play a larger role in the management of carotid disease. Existing research on the tfCAS learning curve, primarily conducted over a decade ago, may not adequately describe the current effect of physician experience on outcomes. Because approximately 30% of perioperative strokes/deaths post-CAS occur after discharge, appropriate thresholds for in-hospital event rates have been suggested to be <4% for symptomatic and <2% for asymptomatic patients. This study evaluates the tfCAS learning curve using Vascular Quality Initiative (VQI) data. METHODS: We identified VQI patients who underwent tfCAS between 2005 and 2023. Each physician's procedures were chronologically grouped into 12 categories, from procedure counts 1-25 to 351+. The primary outcome was in-hospital stroke/death rate; secondary outcomes were in-hospital stroke/death/myocardial infarction (MI), 30-day mortality, in-hospital stroke/transient ischemic attack (stroke/TIA), and access site complications. The relationship between outcomes and procedure counts was analyzed using the Cochran-Armitage test and a generalized linear model with restricted cubic splines. Our results were then validated using a generalized estimating equations model to account for the variability between physicians. RESULTS: We analyzed 43,147 procedures by 2476 physicians. In symptomatic patients, there was a decrease in rates of in-hospital stroke/death (procedure counts 1-25 to 351+: 5.2%-1.7%), in-hospital stroke/death/MI (5.8%-1.7%), 30-day mortality (4.6%-2.8%), in-hospital stroke/TIA (5.0%-1.1%), and access site complications (4.1%-1.1%) as physician experience increased (all P values < .05). The in-hospital stroke/death rate remained above 4% until 235 procedures. Similarly, in asymptomatic patients, there was a decrease in rates of in-hospital stroke/death (2.1%-1.6%), in-hospital stroke/death/MI (2.6%-1.6%), 30-day mortality (1.7%-0.4%), and in-hospital stroke/TIA (2.8%-1.6%) with increasing physician experience (all P values <.05). The in-hospital stroke/death rate remained above 2% until 13 procedures. CONCLUSIONS: In-hospital stroke/death and 30-day mortality rates after tfCAS decreased with increasing physician experience, showing a lengthy learning curve consistent with previous reports. Given that physicians' early cases may not be included in the VQI, the learning curve was likely underestimated. Nevertheless, a substantially high rate of in-hospital stroke/death was found in physicians' first 25 procedures. With the recent Centers for Medicare and Medicaid Services coverage expansion for tfCAS, a significant number of physicians would enter the early stage of the learning curve, potentially leading to increased postoperative complications.

Patient decision-making in the era of transcarotid artery revascularization.

OBJECTIVE: The National Coverage Determination on carotid stenting by Medicare in October 2023 stipulates that patients participate in a shared decision-making (SDM) conversation with their proceduralist before an intervention. However, to date, there is no validated SDM tool that incorporates transcarotid artery revascularization (TCAR) into its decision platform. Our objective was to elicit patient and surgeon experiences and preferences through a qualitative approach to better inform the SDM process surrounding carotid revascularization. METHODS: We performed longitudinal perioperative semistructured interviews of 20 participants using purposive maximum variation sampling, a qualitative technique designed for identification and selection of information-rich cases, to define domains important to participants undergoing carotid endarterectomy or TCAR and impressions of SDM. We also performed interviews with nine vascular surgeons to elicit their input on the SDM process surrounding carotid revascularization. Interview data were coded and analyzed using inductive content analysis coding. RESULTS: We identified three important domains that contribute to the participants' ultimate decision on which procedure to choose: their individual values, their understanding of the disease and each procedure, and how they prefer to make medical decisions. Participant values included themes such as success rates, "wanting to feel better," and the proceduralist's experience. Participants varied in their desired degree of understanding of carotid disease, but all individuals wished to discuss each option with their proceduralist. Participants' desired medical decision-making style varied on a spectrum from complete autonomy to wanting the proceduralist to make the decision for them. Participants who preferred carotid endarterectomy felt outcomes were superior to TCAR and often expressed a desire to eliminate the carotid plaque. Those selecting TCAR felt it was a newer, less invasive option with the shortest procedural and recovery times. Surgeons frequently noted patient factors such as age and anatomy, as well as the availability of long-term data, as reasons to preferentially select one procedure. For most participants, their surgeon was viewed as the most important source of information surrounding their disease and procedure. CONCLUSIONS: SDM surrounding carotid revascularization is nuanced and marked by variation in patient preferences surrounding autonomy when choosing treatment. Given the mandate by Medicare to participate in a SDM interaction before carotid stenting, this analysis offers critical insights that can help to guide an efficient and effective dialog between patients and providers to arrive at a shared decision surrounding therapeutic intervention for patients with carotid disease.

Microplastics and Nanoplastics in Atheromas and Cardiovascular Events.

BACKGROUND: Microplastics and nanoplastics (MNPs) are emerging as a potential risk factor for cardiovascular disease in preclinical studies. Direct evidence that this risk extends to humans is lacking. METHODS: We conducted a prospective, multicenter, observational study involving patients who were undergoing carotid endarterectomy for asymptomatic carotid artery disease. The excised carotid plaque specimens were analyzed for the presence of MNPs with the use of pyrolysis-gas chromatography-mass spectrometry, stable isotope analysis, and electron microscopy. Inflammatory biomarkers were assessed with enzyme-linked immunosorbent assay and immunohistochemical assay. The primary end point was a composite of myocardial infarction, stroke, or death from any cause among patients who had evidence of MNPs in plaque as compared with patients with plaque that showed no evidence of MNPs. RESULTS: A total of 304 patients were enrolled in the study, and 257 completed a mean (±SD) follow-up of 33.7±6.9 months. Polyethylene was detected in carotid artery plaque of 150 patients (58.4%), with a mean level of 21.7±24.5 µg per milligram of plaque; 31 patients (12.1%) also had measurable amounts of polyvinyl chloride, with a mean level of 5.2±2.4 µg per milligram of plaque. Electron microscopy revealed visible, jagged-edged foreign particles among plaque macrophages and scattered in the external debris. Radiographic examination showed that some of these particles included chlorine. Patients in whom MNPs were detected within the atheroma were at higher risk for a primary end-point event than those in whom these substances were not detected (hazard ratio, 4.53; 95% confidence interval, 2.00 to 10.27; P<0.001). CONCLUSIONS: In this study, patients with carotid artery plaque in which MNPs were detected had a higher risk of a composite of myocardial infarction, stroke, or death from any cause at 34 months of follow-up than those in whom MNPs were not detected. (Funded by Programmi di Ricerca Scientifica di Rilevante Interesse Nazionale and others; ClinicalTrials.gov number, NCT05900947.).

Feasibility and efficiency of a new classification based on high-resolution MRI for carotid artery pseudo-occlusion and occlusion: Hybrid revascularization pilot study.

BACKGROUND AND PURPOSE: Studies on changes in the distal internal carotid artery based on high resolution magnetic resonance imaging (HRMRI) are scarce. Herein, we propose a histological classification system for patients with carotid artery pseudo-occlusion or occlusion based on preoperative HRMRI, for which we evaluated the feasibility and clinical implications. MATERIALS AND METHODS: From January 2017 to June 2021, 40 patients with Doppler ultrasound, CTA or MRA suggesting carotid artery occlusion were enrolled in this study. A new classification system based on HRMRI was established and subsequently verified by postoperative specimens. We recorded and analyzed patient characteristics, HRMRI data, recanalization rate, requirements of additional endovascular procedures, complications, and outcomes. RESULTS: Four histological classifications (type Ⅰ-Ⅳ) were identified. According to our classification system, 20 patients (50.00%) were type I, nine (22.50%) were type II, 7 (17.50%) were type III, and four (10.00%) were type Ⅳ. The success rate of recanalization was 88.89% (32/36) in type I-III patients. Four (44.44%) type Ⅱ patients and five (71.43%) type Ⅲ patients suffered from intraoperative dissection. CONCLUSION: Patients identified as types I (pseudo-occlusion) and II (thrombotic-occlusion) were able to be treated via hybrid revascularization with relatively low risk, while patients identified as type III (fibrous-occlusion) required more careful treatment. Recanalization is not suitable for patients identified as type Ⅳ. Our proposed classification system based on HRMRI data can be used as an adjunctive guide to predict the technical feasibility and success of revascularization via a hybrid technique.

Clinical risk factors and features on computed tomography angiography in high-risk carotid artery plaque in patients with type 2 diabetes.

BACKGROUND: High-risk carotid artery plaque (HPR) is associated with a markedly increased risk of ischemic stroke. The aims of this study were: 1) to examine the prevalence of HRP in a cohort of asymptomatic adults with type 2 diabetes (T2D); 2) to investigate the relationship between HRP, established cardiovascular risk factors and computed tomography angiography (CTA) profile; and 3) to assess whether the presence of HRP is associated with an increased risk of major adverse cardiovascular events (MACE). METHODS: This was a retrospective cohort study of T2D asymptomatic patients who underwent carotid endarterectomy (CEA) from January 2018 to July 2021. The carotid atherosclerotic plaque (CAP) was assessed for the presence of ulceration, the presence of lipids, fibrosis, thrombotic deposits, hemorrhage, neovascularization, and inflammation. A CAP presenting at least five of these histological features was defined as a HRP (Group A); in all other cases it was defined as a mild to moderate heterogeneous plaque and no-HRP (Group B). CTA features included the presence of rim sign consisting of thin peripheral adventitial calcification (<2 mm) and internal soft plaque (≥2 mm), NASCET percent diameter stenosis, maximum plaque thickness, ulceration, calcification, and intraluminal thrombus were recorded. Binary logistic regression with Uni- and Multivariate was used to evaluate possible predictors for HRP while multivariable Cox Proportional Hazards was used to assess independent predictors for MACE. RESULTS: One hundred eighty-five asymptomatic patients (mean age 73±8 years, 131 men), undergoing carotid endarterectomy, were included. Of these, 124 (67%) had HRP, and the 61 (33%) did not. Diabetic complications (OR 2.4, 95% CI: 1.1-5.1, P=0.01), NASCET stenosis ≥75% (OR 2.4, 95% CI: 1.2-3.7, P=0.02) and carotid RIM sign (OR 4.3, 95% CI: 3.9-7.3, P<0.001) were independently associated with HRP. However, HRP was not associated with a higher risk of MACE (freedom from MACE at 5 years: HRP 83.4% vs. non HRP 87.8%, P=0.72) or a reduction of survival (5-year survival estimates: HRP 96.4% vs. non HRP: 94.6%, P=0.76). CONCLUSIONS: A high prevalence of HRP (67%) was observed in asymptomatic and elderly T2D patients. Independent predictors of HRP were diabetic complications, NASCET stenosis ≥75% and carotid RIM sign (OR 4.3, 95% CI: 3.9-7.3, P<0.001). HRP was not associated with an increased risk of MACE during a mean follow-up of 39±24 years.

Outcomes of Transcarotid Artery Revascularization Stratified by Institutional Designation: Academic Versus Community Hospitals.

BACKGROUND: The extent of practice setting's influence on transcarotid artery revascularization (TCAR) outcomes is not yet established. This study seeks to assess and compare TCAR outcomes in academic and community-based healthcare settings. METHODS: Retrospective review of prospectively maintained, systemwide TCAR databases from 2 institutions was performed between 2015 and 2022. Patients were stratified based on the setting of surgical intervention (i.e., academic or community-based hospitals). Relevant demographics, medical conditions, anatomic characteristics, intraoperative and postoperative courses, and adverse events were captured for multivariate analysis. RESULTS: We identified 973 patients who underwent TCAR, 570 (58.6%) were performed at academic and 403 (41.4%) at community-based hospitals. An academic facility was defined as a designated teaching hospital with 24/7 service-line coverage by a trainee-led surgical team. Baseline comorbidity between cohorts were similar but cases performed at academic institutions were associated with increased complexity, defined by high cervical stenosis (P < 0.001), prior dissection (P < 0.01), and prior neck radiation (P < 0.001). Intraoperatively, academic hospitals were associated with longer operative time (67 min vs. 58 min, P < 0.001), higher blood loss (55 mLs vs. 37 mLs, P < 0.001), and longer flow reversal time (9.5 min vs. 8.4 min, P < 0.05). Technical success rate was not statistically different. In the 30-day perioperative period, we observed no significant difference with respect to reintervention (1.5% vs. 1.5%, P ≥ 0.9) or ipsilateral stroke (2.7% vs. 2.0%, P = 0.51). Additionally, no difference in postoperative myocardial infarction (academic 0.7% vs. community 0.2%, P < 0.32), death (academic 1.9% vs. community 1.4%, P < 0.57), or length of stay (1 day vs. 1 day, P < 0.62) was seen between the cohorts. CONCLUSIONS: Cases performed at academic centers were characterized by more challenging anatomy, more frequent cardiovascular risk factors, and less efficient intraoperative variables, potentially attributable to case complexity and trainee involvement. However, there were no differences in perioperative outcomes and adverse events between the cohorts, suggesting TCAR can be safely performed regardless of practice setting.

Tenecteplase for Stroke at 4.5 to 24 Hours with Perfusion-Imaging Selection.

BACKGROUND: Thrombolytic agents, including tenecteplase, are generally used within 4.5 hours after the onset of stroke symptoms. Information on whether tenecteplase confers benefit beyond 4.5 hours is limited. METHODS: We conducted a multicenter, double-blind, randomized, placebo-controlled trial involving patients with ischemic stroke to compare tenecteplase (0.25 mg per kilogram of body weight, up to 25 mg) with placebo administered 4.5 to 24 hours after the time that the patient was last known to be well. Patients had to have evidence of occlusion of the middle cerebral artery or internal carotid artery and salvageable tissue as determined on perfusion imaging. The primary outcome was the ordinal score on the modified Rankin scale (range, 0 to 6, with higher scores indicating greater disability and a score of 6 indicating death) at day 90. Safety outcomes included death and symptomatic intracranial hemorrhage. RESULTS: The trial enrolled 458 patients, 77.3% of whom subsequently underwent thrombectomy; 228 patients were assigned to receive tenecteplase, and 230 to receive placebo. The median time between the time the patient was last known to be well and randomization was approximately 12 hours in the tenecteplase group and approximately 13 hours in the placebo group. The median score on the modified Rankin scale at 90 days was 3 in each group. The adjusted common odds ratio for the distribution of scores on the modified Rankin scale at 90 days for tenecteplase as compared with placebo was 1.13 (95% confidence interval, 0.82 to 1.57; P = 0.45). In the safety population, mortality at 90 days was 19.7% in the tenecteplase group and 18.2% in the placebo group, and the incidence of symptomatic intracranial hemorrhage was 3.2% and 2.3%, respectively. CONCLUSIONS: Tenecteplase therapy that was initiated 4.5 to 24 hours after stroke onset in patients with occlusions of the middle cerebral artery or internal carotid artery, most of whom had undergone endovascular thrombectomy, did not result in better clinical outcomes than those with placebo. The incidence of symptomatic intracerebral hemorrhage was similar in the two groups. (Funded by Genentech; TIMELESS ClinicalTrials.gov number, NCT03785678.).

Internal carotid artery-persistent primitive anterior choroidal artery aneurysms: report of two cases and literature review.

PURPOSE: Persistent primitive anterior choroidal artery (PPAChA) is a rare vascular anomaly. The clinical course of internal carotid artery (ICA)-PPAChA aneurysms has not been well described. CASE REPORTS: We report two patients with an ICA-PPChA aneurysm and summarize previously reported cases. RESULTS: Including our two, a total of 10 patients with an ICA-PPAChA aneurysm have been reported. Data were not described for one. Among the remaining nine, five patients (56%) experienced aneurysmal rupture. Five patients underwent surgical clipping and four underwent endovascular coiling. The procedure was completed in all but one patient who had a tiny branch artery adherent to the aneurysm; this patient was converted from clipping to aneurysm coating with a cotton sheet. Among the other eight patients, one who underwent coiling experienced an internal capsule infarction. The remaining seven had a satisfactory postoperative course; however, an asymptomatic occlusion of the PPAChA at its origin was noted on postoperative angiography in one. CONCLUSION: PPChA is associated with a high incidence of aneurysm formation and rupture. During treatment of ICA-PPAChA aneurysms, obstruction of the PPAChA and any surrounding perforating arteries should be avoided to prevent ischemic stroke.

Transcarotid Arterial Revascularization of Symptomatic Internal Carotid Artery Disease: A Systematic Review and Study-Level Meta-Analysis.

BACKGROUND: Transcarotid artery revascularization (TCAR) is an interventional therapy for symptomatic internal carotid artery disease. Currently, the utilization of TCAR is contentious due to limited evidence. In this study, we evaluate the safety and efficacy of TCAR in patients with symptomatic internal carotid artery disease compared with carotid endarterectomy (CEA) and carotid artery stenting (CAS). METHODS: A systematic review was conducted, spanning from January 2000 to February 2023, encompassing studies that used TCAR for the treatment of symptomatic internal carotid artery disease. The primary outcomes included a 30-day stroke or transient ischemic attack, myocardial infarction, and mortality. Secondary outcomes comprised cranial nerve injury and major bleeding. Pooled odds ratios (ORs) for each outcome were calculated to compare TCAR with CEA and CAS. Furthermore, subgroup analyses were performed based on age and degree of stenosis. In addition, a sensitivity analysis was conducted by excluding the vascular quality initiative registry population. RESULTS: A total of 7 studies involving 24 246 patients were analyzed. Within this patient cohort, 4771 individuals underwent TCAR, 12 350 underwent CEA, and 7125 patients underwent CAS. Compared with CAS, TCAR was associated with a similar rate of stroke or transient ischemic attack (OR, 0.77 [95% CI, 0.33-1.82]) and myocardial infarction (OR, 1.29 [95% CI, 0.83-2.01]) but lower mortality (OR, 0.42 [95% CI, 0.22-0.81]). Compared with CEA, TCAR was associated with a higher rate of stroke or transient ischemic attack (OR, 1.26 [95% CI, 1.03-1.54]) but similar rates of myocardial infarction (OR, 0.9 [95% CI, 0.64-1.38]) and mortality (OR, 1.35 [95% CI, 0.87-2.10]). CONCLUSIONS: Although CEA has traditionally been considered superior to stenting for symptomatic carotid stenosis, TCAR may have some advantages over CAS. Prospective randomized trials comparing the 3 modalities are needed.

How I do it? Surgical clipping of a large right internal carotid artery-superior hypophyseal artery aneurysm.

BACKGROUND: Microsurgery alone often proves to be challenging in treating paraclinoid internal carotid artery (ICA) aneurysms, which are known for their complex anatomy. METHOD: A 53-year-old female with a large right ICA-superior hypophyseal artery (SHA) aneurysm underwent clipping repair. Mixed reality technology was utilized in the preoperative planning and anatomical study. During the surgery, the anterior clinoid process was removed intradurally to improve access to the aneurysm neck. The aneurysm was then secured with a long curved clip. The patient's recovery was successful without any complications. CONCLUSION: This report aims to shed light on the intricacies involved in clipping ICA-SHA aneurysms.

Outcomes Following Treatment for Carotid Blowout in Head and Neck Cancer Patients.

OBJECTIVE: The aim of the study was to determine outcomes after interventional radiology treatment of carotid blowout. METHODS: Patients with head and neck cancer and who received interventional radiology treatment for carotid blowout between 2000 and 2022 were included. Pre-treatment, treatment, and post-treatment variables were evaluated. RESULTS: Fourteen patients met inclusion criteria. Eleven patients (78.6%) had a history of radiation. Twelve (85.7%) blowouts occurred within 6 months of recent intervention. Initial treatment was with stenting (n = 9, 64.3%), coil embolization (n = 4, 28.6%), or both (n = 1, 7.1%). Six patients (42.9%) underwent subsequent carotid bypass. Morbidity following treatment included stroke (n = 1) and rebleeding (n = 4). Six-month survival was 57.1%. Of the patients who survived past six months, 5/8 were treated with carotid bypass and coverage. Four patients died of cancer progression, three of rebleeding, and three of medical complications. CONCLUSION: The majority of carotid blowout occurs within 6 months of surgery or radiation. Many who survive will die of cancer progression or medical illness. Carotid bypass with flap coverage may be a worthwhile treatment for carotid blowout and should be considered as an adjunct to endovascular treatment. LEVEL OF EVIDENCE: 4 Laryngoscope, 134:695-700, 2024.