Objective In acute aortic dissection (AAD), the dissection flap can completely cover aortic true lumen (TL) branches, causing dynamic obstruction of visceral and lower extremity branches. This study examined how systolic blood pressure (SBP) reduction improves aortic TL patency and visceral perfusion. Methods 84 patients with acute type A or B aortic dissection and dynamic malperfusion undergoing percutaneous interventional radiology (IR) assessment and treatment from 2012 to 2023 were included. Aortic TL patency was assessed on computer tomography (CT) scans and IR intravascular ultrasound. Antihypertensives were administered, and SBP was monitored at the time of CT and IR intervention. Results Of 84 patients, 58 had aortic TL collapse covering the SMA origin, of which 47 (81%) showed increased TL patency after the average SBP was lowered from 161 to 98 mmHg (39% reduction). There were 10 patients with TL collapse below the level of the SMA, 7 of whom had increased TL patency after the average SBP decreased from 170 to 89 mmHg (48% reduction). 16 patients without aortic TL collapse at any branch level, did not have improved TL patency after the average SBP decreased from 168 to 93 mmHg (45% reduction). BP reduction significantly improved TL patency on McNemar’s test (p<0.001). The random effects model revealed that elevated SBP was associated with TL collapse (OR 1.029, p = 0.001). Conclusion Lowering SBP in AAD reduces dynamic malperfusion and improves visceral perfusion. Upon diagnosis, prompt initiation and maintenance of SBP reduction as low as tolerated is beneficial and recommended until a definitive mechanical solution for the malperfusion is complete.

Endovascular therapy provides a new treatment modality for patients with aortic disease. By avoiding the morbidity of open surgery, endovascular approaches make treatment possible for a larger array of patients. However, the durability and long-term survival benefit of endovascular aortic intervention require further discussion and additional follow-up. We believe that the characterization of the role of endovascular therapy involves close risk-benefit analysis based on patient risk, disease presentation, native and pathological anatomy, and long-term outlook. Through review of the randomized prospective literature and relevant retrospective data, we explore the role of catheter-based solutions in abdominal and thoracic aortic disease, with a focus on aortic aneurysm and aortic dissection (AD). For patients with appropriate anatomy, endovascular aortic repair (EVAR) has largely supplanted open aortic repair (OAR) in the treatment of abdominal aortic aneurysm (AAA), both in the elective setting and during rupture. Similarly, thoracic endovascular aortic repair (TEVAR) has gained popularity in treating disease of the descending thoracic aorta, in both aneurysmal degeneration and AD. Similar adoption has been seen in treating other disease states, namely traumatic aortic injury. However, we recognize the current limitations of endovascular therapy and detail the innovations being pursued to advance endovascular therapy in the future.

OBJECTIVE:Endovascular iliofemoral venous stenting has low morbidity; however, in stent re-stenosis (ISR) remains a significant complication that may require re-intervention. This single centre, retrospective study aimed to evaluate ISR biopsy findings and risk factors for stent failure in patients with iliofemoral venous stents. METHODS:Eighty-four patients (mean age 45.3 ± 16.0 years) who underwent iliac vein stenting and endovascular biopsies between January 2008 and January 2021 were included. Catheter based venography and endovascular biopsies were performed at 3 - 12 and 12 - 24 months after stenting. Logistic regression and Cox regression analyses were conducted to assess the factors associated with severe ISR (ISR degree ≥ 50%) and stent failure. Stent patency time was estimated using Kaplan-Meier curves. RESULTS:Over a mean follow up of 67.4 ± 43.4 months, stent failure occurred in 27 patients (32.1%), including 10 (11.9%) before the second venographic evaluation. At the first biopsy, 38.1% exhibited fresh or organising thrombus, while 61.9% exhibited old thrombus or diffuse intimal thickening (DIT). At the second biopsy, 28.1% had fresh or organising thrombus and 71.9% had old thrombus or DIT. A prothrombotic state (odds ratio 17.862; p = .003) was the significant risk factor for severe ISR within 12 months after stenting, whereas age > 45 years was protective (odds ratio 0.102; p = .009). Patients with fresh or organising thrombus had a statistically significantly higher incidence of stent failure compared with those with old thrombus or DIT (first: 50.0 vs. 21.2%, p = .008; second: 56.3 vs. 19.5%, p = .010). Jalaie type 3 lesions exhibited statistically significantly greater ISR than Jalaie type 2 at both time points (p = .008 and p = .001). Severe ISR between 12 - 24 months after stenting was the predictor for stent failure (hazard ratio 21.573; p = .001). CONCLUSION:ISR biopsy demonstrating fresh or organising thrombus was associated with a significantly higher risk of stent failure. Early identification of high risk patients can inform risk stratification and post-stenting management strategies.

Background: Visceral malperfusion is a serious complication of acute aortic dissection. Currently, diagnosis relies on signs of end-organ failure, which may be clinically obscure and delay crucial treatment. Objective: The aim was to investigate external iliac (IA) and superior mesenteric artery (SMA) pressures in cases where both vessels originate exclusively from the true lumen to develop and validate a novel early indicator of visceral malperfusion. Methods: Endovascular pressure measurements from 488 patients with acute aortic dissection were analyzed. Exclusion criteria included static obstruction of the branch vessel or substantial re-entry tear below the SMA origin. Results: In acute type A aortic dissection, 69 out of 244 (28.3%) patients had at least 1 common IA and the SMA with exclusive true lumen perfusion. Among all patients with acute type A aortic dissection, 41 (16.8%) patients with 49 external IA pressure measurements met inclusion criteria. Pressures in right external IA (n = 27) and left external IA (n = 22) correlated significantly with SMA perfusion pressure (r2 = 0.86 [95% CI, 0.71-0.93; P = 1.03E-08] and r2 = 0.86 [95% CI, 0.69-0.94; P = 2.85E-07], respectively). In settings of acute type B aortic dissection, 81 out of 244 (33.2%) patients had at least 1 common IA and the SMA with exclusive true lumen perfusion. Among all patients with acute type B aortic dissection, 35 (14.3%) patients with 44 external IA pressure measurements met inclusion criteria. The right external IA (n = 24) and left external IA (n = 20) pressures correlated significantly with SMA perfusion pressure (r2 = 0.92 [95% CI, 0.83-0.97; P = 1.59E-10] and r2 = 0.87 [95% CI, 0.70-0.95; P = 6.12E-07], respectively). Conclusions: In acute aortic dissection where the SMA and a common IA are supplied exclusively by the true lumen, external IA systolic pressures correlate significantly with SMA systolic pressures. In this group, therefore, clinical loss of the femoral pulse likely indicates significantly decreased SMA pressures, raising concern for visceral malperfusion, possibly before visceral enzymes can respond. We believe that computed tomography reports should highlight this anatomical finding to alert the clinical team monitoring the patient. (JTCVS Open 2025;23:34-43)

Background: Interventional therapies to relieve chronic deep vein thrombosis (DVT) fail through inability to penetrate, cross, and remove the occlusion. Development of suitable tools requires fundamental understanding of chronic DVT mechanical properties and a reliable model for testing. Methods: Female farm swine underwent a novel, endovenous generation of long-segment unilateral iliac vein thrombosis. Thrombus was confirmed via venogram, intravascular ultrasound, and transabdominal duplex for 14 days. Thrombus components were quantified via histology. Thrombus mechanical properties were assessed via uniaxial compression. Results: Among seven swine, technical success was 100%. Compared to subacute thrombi (7-day), chronic thrombi (14-day) showed organizing thrombus with diffuse myointimal thickening and collagen matrix formation on histology. The thrombi collagen content was 41% versus 55% (p = 0.17) and the thrombus erythrocyte percentage was 4.3% versus 2.2%, p = 0.21 in 7- versus 14-day thrombi, respectively. The onset point (compression required to load the thrombus fiber network) was 66.6% versus 35.3% (p = 0.004), the secant modulus (resistance to deformation) measured at the onset point was 153.8 versus 275.99 kPa (p = 0.18), and the average shear constant (resistance to shearing), as defined by the Yeoh hyperelastic model, was 1.85 kPa versus 2.85 kPa in 7- versus 14-day thrombi. Conclusions: This study demonstrates the feasibility of an endovenous model generating chronic unilateral venous thrombi in 2 weeks with similar anatomy to humans and provides critical mechanical properties of thrombi for future research.

Objectives Acute aortic dissection is a rare yet life-threatening complication associated with transcatheter aortic valve replacement (TAVR). Given its low incidence, the characteristics and risk factors remain inadequately investigated. Methods Between 2011 and 2023, a total of 2558 TAVR procedures were performed at the University of Michigan. Among these, 12 patients (0.47%) developed aortic dissection. Additionally, 3 post-TAVR patients from other institutions presented with aortic dissection and were treated at our institution, yielding a total of 12 type A and 3 type B aortic dissections. Results The median age was 79.5 years, and 5 (33.3%) exhibited end-organ malperfusion affecting the brain (n = 3), legs (n = 3), and kidneys (n = 1). TAVR device migration requiring repositioning was observed in 40% (6 out of 15) of cases. In type A dissections, the entry tear consistently occurred along the greater curvature. Patients with type A dissections had a larger pre-TAVR aortic diameter than those without dissection (41.6 mm vs 34.5 mm; P < .001). Preexisting aortic dilation (≥45 mm) was associated with a significantly increased risk of type A dissection (odds ratio, 12.0; 95% confidence interval 3.0-50.6; P < .001). Type A dissection was managed with open repair in 7 patients (58.3%), all of whom survived 30 days, and with endovascular aortic repair in 4 patients (33.3%), all of whom experienced mortality; 1 patient received palliative care. All type B dissections were successfully treated with endovascular repair. Conclusions TAVR-related aortic dissection is characterized by preexisting aortic risk factors with various mechanisms. Current surgical guidelines recommending aortic repair for dilatation ≥45 mm should be strongly considered in patients undergoing TAVR evaluation.

Interdisciplinary teams offer potential advantages over siloed care models in complex cardiovascular disease management. Consensus guidelines for aortic management have increasingly identified the interdisciplinary aortic team as a key component in delivering quality care. Acute aortic syndromes are a subset of high acuity and lethal aortic pathologies that may benefit from an interdisciplinary approach. The advantages of the interdisciplinary aortic team model in the management of acute aortic syndromes and barriers to implementation are discussed.

Background Balloon pulmonary angioplasty for chronic thromboembolic pulmonary hypertension (CTEPH) is limited by a lack of safe and effective tools for crossing these lesions. We aim to identify a safety window for an intraluminal crossing device in this vascular bed by studying the piercing properties of pulmonary arterial vessel walls and intraluminal CTEPH lesion specimens. As a secondary objective, we also describe the histopathologic features of CTEPH lesions. Methods Specimens were procured from 9 patients undergoing pulmonary endarterectomy. The specimens were subsampled and identified grossly as arterial wall or intraluminal CTEPH lesions. The force needed for tissue penetration was measured using a 0.38-mm (0.015-in) diameter probe in an ex vivo experimental model developed in our lab. Concurrent histology was also performed. Results The mean force needed to penetrate the arterial wall and intraluminal CTEPH lesions was 1.75 ± 0.10 N (n = 121) and 0.30 ± 0.04 N (n = 56), respectively (P < .001). Histology confirmed the presence of intimal hyperplasia with calcium and hemosiderin deposition in the arterial wall as well as an old, organized thrombus in the lumen. Conclusions The pulmonary arterial wall is friable and prone to perforation during instrumentation with workhorse coronary guide wires. However, the results of this study demonstrate that a much lower force is needed for the 0.38-mm (0.015-in) probe to penetrate an intraluminal CTEPH lesion compared to pulmonary arterial intima. This finding suggests the existence of a safety window for lesion-crossing devices, enabling effective balloon pulmonary angioplasty.

Introduction: Iliac vein compression syndrome (IVCS) is present in over 20% of the population and is associated with left leg pain, swelling, and thrombosis. IVCS symptoms are thought to be induced by altered pelvic hemodynamics, however, there currently exists a knowledge gap on the hemodynamic differences between IVCS and healthy patients. To elucidate those differences, we carried out a patient-specific, computational modeling comparative study.Methods: Computed tomography and ultrasound velocity and area data were used to build and validate computational models for a cohort of IVCS (N = 4, Subject group) and control (N = 4, Control group) patients. Flow, cross-sectional area, and shear rate were compared between the right common iliac vein (RCIV) and left common iliac vein (LCIV) for each group and between the Subject and Control groups for the same vessel.Results: For the IVCS patients, LCIV mean shear rate was higher than RCIV mean shear rate (550 ± 103 s−1 vs. 113 ± 48 s−1, p = 0.0009). Furthermore, LCIV mean shear rate was higher in the Subject group than in the Control group (550 ± 103 s−1 vs. 75 ± 37 s−1, p = 0.0001). Lastly, the LCIV/RCIV shear rate ratio was 4.6 times greater in the Subject group than in the Control group (6.56 ± 0.9 vs. 1.43 ± 0.6, p = 0.00008).Discussion: Our analyses revealed that IVCS patients have elevated shear rates which may explain a higher thrombosis risk and suggest that their thrombus initiation process may share aspects of arterial thrombosis. We have identified hemodynamic metrics that revealed profound differences between IVCS patients and Controls, and between RCIV and LCIV in the IVCS patients. Based on these metrics, we propose that non-invasive measurement of shear rate may aid with stratification of patients with moderate compression in which treatment is highly variable. More investigation is needed to assess the prognostic value of shear rate and shear rate ratio as clinical metrics and to understand the mechanisms of thrombus formation in IVCS patients.

Numerous organisms play a host role for a variety of marine and freshwater diatoms and many have yet to be studied in detail. In particular, along the Argentine coast, there have been very few studies on epizoic diatoms. Through the analysis of ascidians, decapods, echinoderms and gastropods sampled from Atlantic Patagonian waters (San Jorge Gulf), this is the first study in the region on epizoic diatoms found on benthic macroinvertebrates. Thirty-one potential host samples, including 14 macroinvertebrates taxa, were examined from different stations. The epizoic diatom taxa found at the highest relative abundance, namely Cocconeis patagonica sp. nov., Pseudogomphonema kamtschaticum and Tabularia investiens, were analyzed using light and electron microscopy, and hence they are described in detail and compared with other species. Cocconeis patagonica sp. nov. belongs to the C. scutellum complex, but its particular raphe-valve (RV) valvocopula ultrastructure and striation defines it as new. Diagnostic characters are discussed for T. investiens. Pseudogomphonema kamtschaticum is reported for the first time in the Atlantic Patagonian waters.

Eagle syndrome is defined by a spectrum of clinical presentations related to an elongated styloid process or calcified stylohyoid ligament, in the neck, which impinges on the adjacent nerves, arteries, or veins. It is an uncommon finding but one that should be considered in clinical and imaging practice. A variety of symptoms can result. The diagnosis is often delayed, particularly if it is not considered. Although the elongated styloid process may be seen on plain X-ray, contrast-enhanced computerized tomographic angiography (CTA) is considered the diagnostic test of choice. There is, however, a role for ultrasound in both the diagnosis and consideration of the differential diagnosis of Eagle syndrome. Vascular ultrasound specialists should be aware of this entity and be prepared to characterize the findings with ultrasound. Although medical management or endovascular approaches have been described, generally, surgical excision of the styloid process is recommended. Outcomes from such treatment tend to be excellent. Most reports describe a single patient or small series, and the role of duplex scanning has not been discussed. This patient is presented to allow a review of Eagle syndrome, classify the types, and introduce the details of modern high-resolution color duplex scanning in its management.

Objective: The role of thoracic endovascular aortic repair for chronic type B aortic dissection remains controversial. Clinical outcomes of thoracic endovascular aortic repair with recently implemented aortic septotomy strategy were compared with stand-alone thoracic endovascular aortic repair. Methods: Between 2008 and 2020, 88 patients with chronic type B aortic dissec-tion and degenerative aortic aneurysm underwent a thoracic endovascular aortic repair with or without adjunctive aortic septotomy, consisting of 36 (41%) with de novo chronic type B aortic dissection and 52 (59%) with residual chronic type B aortic dissection after type A aortic dissection repair. Results: Aortic septotomy was performed in 31 patients (35%) to optimize the proximal (3/31;10%) and distal (31/31;100%) landing zones. The aortic septotomy techniques comprised laser aortic septotomy in 16 patients (52%) and cheese wire septotomy in 15 patients (48%) with a 97% overall technical success rate. The median time interval between aortic dissection occurrence and thoracic endo-vascular aortic repair was 1.2 years. During follow-up, there were 12 (21%) sudden deaths and 17 (30%) combined aorta-related and sudden deaths in the nonaortic septotomy group, whereas there were no deaths in the septotomy group (P<.001). Patients without aortic septotomy required aortic reinterventions more frequently than those with aortic septotomy (30% vs 7%; P 1/4 .014), and 77% of these procedures were related to residual retrograde false lumen flow. Positive aortic remodeling was confirmed in 90% and 37% in the aortic septotomy and nonseptotomy groups, respectively (P <.001). Conclusions: Stand-alone thoracic endovascular aortic repair outcomes without adjunctive procedures for chronic type B aortic dissection remain unfavorable. In contrast, landing zone optimization using aortic septotomy resulted in a remarkably higher positive aortic remodeling rate. Routine aortic septotomy strategy may positively affect long-term chronic type B aortic dissection survival and expand thoracic endovascular aortic repair candidacy. (J Thorac Cardiovasc Surg 2023;165:1776-86)

Kützing described the species Achnanthes capensis Kützing along with the variety Achnanthes capensis ß multiarticulata Kützing. The latter was based on ‘Achnanthes striata Suhr’, a name first mentioned, without description or figure, in Drège’s Zwei pflanzengeographische Documente. ‘Achnanthes striata’ became a synonym of Achnanthes capensis in Kützing’s protologue without it ever being validly published. All original specimens of Achnanthes capensis, A. capensis ß multiarticulata and A. striata are from Table Bay, Cape Province, Cape of Good Hope, South Africa. This account describes specimens from original material for all three names in Achnanthes and clarifies their relationships. As no morphological differences among these three named taxa could be found based on light and scanning electron microscopy observations, we place the other two names into A. capensis, as this name has priority. In short, A. capensis ß multiarticulata and A. striata are synonyms of Achnanthes capensis.

We performed a contemporary assessment of clinical and radiographic factors of stroke after thoracic endovascular aortic repair (TEVAR). Patients undergoing TEVAR from 2006 to 2017 were identified. We assessed clinical and radiographic data, including preoperative head and neck computed tomography, Doppler ultrasonography, and intraoperative angiography. Our primary outcome was stroke after TEVAR. Four hundred seventy-nine patients underwent TEVAR, mean age 68.1 ± 19.5 years, 52.6% male. Indications for TEVAR included aneurysms (n = 238, 49.7%) or dissections (n = 152, 31.7%). Ishimaru landing zones were Zone 2 (n = 225, 47.0%), Zone 3 (n = 151, 31.5%), or Zone 4 (n = 103, 21.5%). Stroke occurred in 3.8% (n = 18) of patients, with 1.9% (8) major events (modified Rankin Scale >3). Pathophysiology was predominantly embolic (n = 14), and occurred in posterior (n = 6), anterior (n = 6), or combined circulation (n = 4), and in the left hemisphere (n = 10) or bilateral (n = 6). Univariate analysis suggested use of lumbar drain (33.3% versus 57.2%, P = 0.04), inability to revascularize the left subclavian artery (16.7% vs 5.2%, P = 0.04) and number of implanted components (2.5 ± 1.2 vs 2.0 ± 0.97, P = 0.03) were associated with stroke. Multivariable analysis identified number of implanted components (OR 1.7, 95%CI 1.17-2.67 P = 0.00) and inability to revascularize the left subclavian artery as independent predictors of stroke. Stroke was associated with a higher perioperative mortality (27.8% vs 3.9%, P < 0.01). Stroke after TEVAR is primarily embolic in nature and related to both anatomic and procedural factors. This may have important implications for device development in the era of endovascular arch repair.

Objective: The objective of this study was to determine the pathologic features of venous in-stent stenosis over time occurring in bare metal stents. Methods: Endovascular biopsy samples were obtained prospectively from venous bare metal stents implanted in 2009 through 2018. All samples were formalin-fixed, paraffin-embedded and stained with hematoxylin and eosin. Samples were examined by a cardiovascular pathologist to estimate the amount of its constituent components, which included fresh thrombus, organizing thrombus, old thrombus, or diffuse intimal thickening (DIT), and pathologic features including calcification, neovascularization, and hemosiderin deposition. This pathologic characterization was correlated with time following stent implantation to discern time-dependence of pathologic evolution of in-stent stenosis using both descriptive statistics and binary logistic regression. Results: A total of 254 post-stent venograms with biopsies of in-stent contents from 148 unique patients were studied. Fresh thrombus and organizing thrombus were both present across all studied time intervals. Old thrombus was seen beginning at approximately 2 weeks and DIT at approximately 4 weeks. Calcification was a rare finding encountered at later time intervals. The prevalence of each component varied with time: the probability of encountering fresh thrombus (P = .010) and organizing thrombus (P = .008) decreased over time. By contrast, the probability of finding DIT (P = .002) and calcifications (P < .001) increased over time. The presence of old thrombus, neovascularization, or hemosiderin did not demonstrate time dependence. Diffuse intimal thickening was frequently seen along with organizing thrombus as well as independently, and in many instances, these two features were directly merged. Conclusions: The evolution of human venous in-stent restenosis appears to follow a time-dependent course, sug-gesting a possible progressive evolution from fresh and organizing thrombus to DIT. Contrasted with the literature on arterial in-stent restenosis, vein in-stent restenosis may have an increased thrombus prevalence (both organizing and old thrombus). DIT is a primary feature of late in-stent stenosis and may explain in part why many of these lesions may not respond to thrombolytic or anticoagulant treatment alone.