Lewis, Andrew R.

Background: Segmental arterial mediolysis (SAM) is a non-inflammatory vasculopathy that primarily affects the abdominal visceral arteries leading to hemorrhage, ischemia, or pseudoaneurysms. Its presentation can be mimicked by other vasculopathies including vasculitis involving the medium-sized blood vessels making it difficult to diagnose. Case Presentation: A 55-year-old woman presented with a two-hour history of sudden-onset, severe epigastric pain radiating to the chest. She was noted to be hypotensive with low hemoglobin 8.8 g/dL suspicious for a hemorrhagic cause. Her case was complicated by elevated international normalized ratio 3.7 in the setting of warfarin therapy for the mechanical mitral valve. The remainder of her complete blood count, complete metabolic panel, inflammatory markers, autoantibody serologies, and infectious testing were negative. Abdominal computed tomography angiogram revealed hemoperitoneum, bilateral renal infarctions, a large mesenteric hematoma, aneurysmal disease of the common hepatic and inferior mesenteric arteries, thrombosis and proximal dissection of the superior mesenteric artery, acute thrombosis of the left external iliac vein, and multiple sites of arterial extravasation from the pancreaticoduodenal artery and its branches. Mesenteric artery angiogram showed multivessel visceral artery aneurysms and stenoses characteristic of SAM for which she underwent transcatheter arterial embolization of the bleeding vascular bed. We provide a narrative literature review with a focus on common presentations and differentiating characteristics of vasculopathies that can involve medium-sized blood vessels. It is important to accurately diagnose SAM and its potential mimics as management strategies differ. Conclusions: SAM presents with medium vessel vasculopathy without vasculitis. Differentiation from mimics can be difficult but aided by familiarity of their characteristic findings and differentiating clinical characteristics.

Objectives Heritable connective tissue disorders (HCTDs), including hypermobile Ehlers-Danlos syndrome (hEDS) and hypermobile spectrum disorder (HSD), have complex clinical manifestations, but the prevalence of left common iliac vein (LCIV) compression in these groups is not well known. This study aimed to compare the prevalence of significant LCIV compression in patients with hEDS, HSD, and healthy controls. Methods This retrospective, IRB-approved, single-center study analyzed 109 patients (25 hEDS, 64 HSD, 20 controls) who underwent contrast-enhanced abdominal and pelvic CT imaging from 2020 to 2023. LCIV compression was measured on axial CT, with >50% luminal narrowing defined as significant. Statistical analyses included chi-square tests, odds ratios, and t -tests. Interrater reliability was evaluated using intraclass correlation coefficients. Results Significant LCIV compression occurred in 68.0% of hEDS, 65.6% of HSD, and 35.0% of controls ( p = 0.034). Both hEDS ( p = 0.027) and HSD ( p = 0.015) groups had significantly higher compression rates than controls, with no statistically significant difference between the two clinical groups ( p = 0.831). Odds of compression were nearly fourfold greater in hEDS (OR 3.95) and HSD (OR 3.54) compared to controls. Conclusion LCIV compression is significantly more prevalent in patients with hEDS and HSD than in healthy controls, warranting further investigation of its clinical significance.

Abstract May-Thurner physiology (MTP) can lead to various congestion syndromes due to compression of the left common iliac vein (LCIV) by the right common iliac artery (RCIA). This compression may result in venous reflux through the lumbar vein, leading to congestion of the spinal epidural venous plexus (EVP), which could contribute to refractory headaches. This case report details the clinical course of a patient with severe refractory new daily persistent headache associated with MTP who underwent ascending lumbar vein (ALV) embolization. The patient is a 59-year-old female with a 3-year history of daily persistent headache which failed multiple migraine prevention therapies and minimally invasive procedures. Imaging studies revealed significant LCIV compression by the RCIA, retrograde ALV flow, and EVP congestion. The patient underwent ALV embolization, resulting in significant symptomatic relief. At the 22-month follow-up, headache severity reduced by 80%, with the patient no longer requiring routine headache medications. Additionally, treatment of associated pelvic congestion syndrome through gonadal vein embolization resolved longstanding associated pelvic pain and pressure. This case highlights the role of venous congestion in refractory headache syndromes and underscores the potential of targeted venous interventions, such as embolization, in their management. The findings expand on emerging evidence linking venous compression syndromes to headache pathophysiology and support exploring interventional strategies as viable treatment options for selected patients. Further research is needed to validate these findings and establish evidence-based guidelines for clinical practice.

The authors have published on a unique subset of patients whose headaches worsened in the Trendelenburg position and who on time-resolved MR angiography demonstrated left renal vein compression (nutcracker physiology) with retrograde left second lumbar vein (L2LV) flow and regional spinal epidural venous plexus (EVP) congestion. We hypothesized that the spinal EVP congestion subsequently causes a secondary congestion of the cerebral venous system, which then leads to an elevation of CSF pressure above that individuals CSF pressure set point. This results in a daily headache from onset. Thus, eliminating the spinal EVP could conceivably improve or eliminate the manifested headache syndrome. We now present a case series of four patients with long-term follow-up utilizing lumbar vein coil embolization as a new therapeutic approach. In each patient, the MR angiography findings were verified by catheter-based venography. Treatment consisted of endovascular embolization of the second lumbar vein. Four patients have had coil embolization of which three are 1 year or longer from their procedure while one is 10 months posttreatment. All patients were women. Duration of daily headache prior to embolization ranged from 4 to 8 years. Post-embolization: Three patients are either headache free or 90–95% improved with substantial pain free time. There were no procedure-related complications. Our results suggest that embolization of L2LV in a specific patient population with nutcracker physiology may substantially improve head pain issues. This is a minimally invasive outpatient technique with no apparent side effects.

Objective Compression of the left renal vein by the superior mesenteric artery, known as nutcracker phenomenon (NCP), can cause retrograde flow and congestion in communicating venous systems. It has recently been speculated that NCP can result in retrograde flow and congestion of the lumbar veins and epidural venous plexus (EVP), thereby affecting the central nervous system. This study describes the novel use of time-resolved magnetic resonance angiography (trMRA) to evaluate for retrograde left second lumbar vein (L2LV) flow and early EVP enhancement in patients with chronic daily headache (CDH) with and without NCP. Methods A retrospective analysis was performed of 31 patients with CDH (27 females and 4 males; median age, 38 years [range, 18–63 years]) who underwent trMRA centered over the L2LV to evaluate the direction of blood flow and presence of early EVP enhancement from May 2020 to March 2022. Descriptive statistics were performed, and anatomic associations were analyzed in patients with and without retrograde L2LV flow and early EVP enhancement. The accuracy of magnetic resonance imaging findings in detecting these flow patterns was also assessed. Results Patients with NCP who demonstrated narrowing of the left renal vein, a positive beak sign (P = 0.052), decreased aortomesenteric distance (P = 0.038), and decreased SMA angle demonstrated increased rates of retrograde L2LV flow and early EVP enhancement. A positive beak sign was 83% specific, and an aortomesenteric distance of ≤6.5 mm was 61% sensitive and 83% specific for identifying retrograde L2LV flow with early regional EVP enhancement in patients with CDH. Conclusions Retrograde L2LV flow with early EVP enhancement in CDH patients can be effectively evaluated using trMRA and was seen with greater propensity in those patients with NCP.

Introduction: Nearly half of the adult population in the United States has been diagnosed with hypertension. Adrenal hormonal hypersecretion is a leading cause of secondary hypertension. Adrenal vein sampling (AVS) may assist in differentiating between unilateral and bilateral adrenal hormonal hypersecretion to identify patients who are candidates for adrenalectomy. We reviewed the use of AVS at our institution along with associated outcomes after adrenalectomy. Materials and Methods: A retrospective chart review was conducted of patients with a diagnosis of primary hyperaldosteronism (PA) or adrenocorticotropic hormone-independent Cushing syndrome (AICS) and who underwent adrenalectomy between January 1, 2010, and December 1, 2021. Patient data of baseline characteristics, preoperative workup, including AVS, and postoperative outcomes were collected and analyzed. Results: Seventy-one patients were identified in the study period (48 PA and 23 AICS). Computed tomography scan identified unilateral adrenal nodules in 52 patients (29 left; and 23 right), bilateral nodules in 13 patients, and no nodules in 6 patients. AVS was performed in 45 patients with PA (93%) and 5 patients with AICS (21%). After surgery, the number of PA patients with hypokalemia or requiring potassium supplementation significantly decreased after adrenalectomy (before surgery: 33 [68.7%]; and after surgery: 5 [10.4%], P < .01). The number of medications required for hypertension in AICS patients also significantly decreased. No major adverse events were noted. Conclusions : Our long-term experience demonstrates the ongoing use of AVS during workup of patients with primary hyperaldosteronism and for select patients with adrenocorticotropic hormone-independent Cushing syndrome. However, a low level of discordance between imaging and AVS findings in PA patients suggests that there may be a subset of patients in whom preoperative AVS is not necessary.

Retrieval of tip-embedded inferior vena cava filters using endobronchial forceps is a well-described technique. The tip of dorsally tilted filters may be in proximity to the right renal artery, increasing the risk of arterial injury during retrieval. We present one case that illustrates renal artery injury requiring emergent stent graft repair. The three subsequent cases illustrate techniques that avoid renal artery injury using a femoral and jugular approach with the assistance of an arterial fiducial wire. Renal artery injury is a potential complication during retrieval of filters using endobronchial forceps that can be prevented with careful planning.

AbstractThermal ablation is widely regarded as definitive therapy for early-stage hepatocellular carcinoma, but its efficacy decreases in tumors greater than 3 cm. Extensive clinical studies have supported improved outcomes provided through combining transarterial embolic therapy with ablation in the treatment of larger tumors. This article will provide a survey of the science and data for combination therapy in both thermal and nonthermal ablation modalities, as well as describe emerging applications.