Editor's Choice -- European Society for Vascular Surgery (ESVS) 2024 Clinical Practice Guidelines on the Management of Abdominal Aorto-Iliac Artery Aneurysms.

OBJECTIVE: The European Society for Vascular Surgery (ESVS) has developed clinical practice guidelines for the care of patients with aneurysms of the abdominal aorta and iliac arteries in succession to the 2011 and 2019 versions, with the aim of assisting physicians and patients in selecting the best management strategy. METHODS: The guideline is based on scientific evidence completed with expert opinion on the matter. By summarising and evaluating the best available evidence, recommendations for the evaluation and treatment of patients have been formulated. The recommendations are graded according to a modified European Society of Cardiology grading system, where the strength (class) of each recommendation is graded from I to III and the letters A to C mark the level of evidence. RESULTS: A total of 160 recommendations have been issued on the following topics: Service standards, including surgical volume and training; Epidemiology, diagnosis, and screening; Management of patients with small abdominal aortic aneurysm (AAA), including surveillance, cardiovascular risk reduction, and indication for repair; Elective AAA repair, including operative risk assessment, open and endovascular repair, and early complications; Ruptured and symptomatic AAA, including peri-operative management, such as permissive hypotension and use of aortic occlusion balloon, open and endovascular repair, and early complications, such as abdominal compartment syndrome and colonic ischaemia; Long term outcome and follow up after AAA repair, including graft infection, endoleaks and follow up routines; Management of complex AAA, including open and endovascular repair; Management of iliac artery aneurysm, including indication for repair and open and endovascular repair; and Miscellaneous aortic problems, including mycotic, inflammatory, and saccular aortic aneurysm. In addition, Shared decision making is being addressed, with supporting information for patients, and Unresolved issues are discussed. CONCLUSION: The ESVS Clinical Practice Guidelines provide the most comprehensive, up to date, and unbiased advice to clinicians and patients on the management of abdominal aorto-iliac artery aneurysms.

Safety and Efficacy of Inner Branched Stent-Graft in the Treatment of Aortic Arch Disease: A Systematic Review.

OBJECTIVE: To provide a descriptive overview on the contemporary outcomes of thoracic endovascular arch repair with inner branched endoprosthesis (bTEVAR) for the treatment of aortic arch pathologies. METHODS: A comprehensive literature search was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Pre-defined search terms were used to interrogate PubMed and OVID Medline databases from January 1999 to July 2022. Patient characteristics, indication for treatment, procedural data, mortality rates, postoperative complications, and reintervention rate during follow-up were evaluated. RESULTS: Nineteen articles were included, encompassing a total of 618 patients who received bTEVAR, most of which were double-branched (63.9%, n=395). The main indication for treatment was aneurysm secondary to chronic aortic dissection (38.8%, n=240/618) with a mean maximum diameter of 58.3±11.4 mm. Pooled mean technical success rate was 97.4±4.4% (95% confidence interval [CI]=95.1%-99.5%); 2 and 3 patients required conversion to chimney technique and open repair, respectively. Among the pooled rates of early complications, postoperative stroke was the highest (10.5%; 95% CI=6.8%-14.3%). Thirty-day and in-hospital mortality rate was 5.5% (95% CI=2.6%-9.7%). Forty patients (6.5%; 95% CI=2.5%-9.5%) required early reintervention. During a mean follow-up of 20.7±13.5 months, the mortality rate was 18.2% (n=108/593; 95% CI=8.6%-20.6%) where 12 (11.1%) were aortic-related. Pooled late reintervention rate was 9.6% (95% CI=4.8%-14.3%). Comparison of demographics and outcomes found no significant difference between single and double bTEVAR. CONCLUSION: Branched thoracic endovascular aortic repair is a promising approach for aortic arch pathologies with a high technical success rate despite a steep learning curve. However, contemporary outcomes reflect that postoperative stroke remains the predominant concern. Further experience and long-term follow-up are required to sufficiently elucidate the safety and durability of bTEVAR in the management of aortic pathologies for high-risk patients. CLINICAL IMPACT: This systematic review summarized the contemporary outcomes of thoracic endovascular aortic repair with different inner branched stent-grafts for the management of aortic arch pathologies. Pooled results from nineteen studies with 618 patients demonstrated a high technical success rate and an acceptable mortality rate. However, postoperative stroke remains the major concern. Long-term follow-up is needed to evaluate its durability.

Outcomes After Endovascular Aortic Intervention in Patients With Connective Tissue Disease.

Importance: Endovascular treatment is not recommended for aortic pathologies in patients with connective tissue diseases (CTDs) other than in redo operations and as bridging procedures in emergencies. However, recent developments in endovascular technology may challenge this dogma. Objective: To assess the midterm outcomes of endovascular aortic repair in patients with CTD. Design, Setting, and Participants: For this descriptive retrospective study, data on demographics, interventions, and short-term and midterm outcomes were collected from 18 aortic centers in Europe, Asia, North America, and New Zealand. Patients with CTD who had undergone endovascular aortic repair from 2005 to 2020 were included. Data were analyzed from December 2021 to November 2022. Exposure: All principal endovascular aortic repairs, including redo surgery and complex repairs of the aortic arch and visceral aorta. Main Outcomes and Measures: Short-term and midterm survival, rates of secondary procedures, and conversion to open repair. Results: In total, 171 patients were included: 142 with Marfan syndrome, 17 with Loeys-Dietz syndrome, and 12 with vascular Ehlers-Danlos syndrome (vEDS). Median (IQR) age was 49.9 years (37.9-59.0), and 107 patients (62.6%) were male. One hundred fifty-two (88.9%) were treated for aortic dissections and 19 (11.1%) for degenerative aneurysms. One hundred thirty-six patients (79.5%) had undergone open aortic surgery before the index endovascular repair. In 74 patients (43.3%), arch and/or visceral branches were included in the repair. Primary technical success was achieved in 168 patients (98.2%), and 30-day mortality was 2.9% (5 patients). Survival at 1 and 5 years was 96.2% and 80.6% for Marfan syndrome, 93.8% and 85.2% for Loeys-Dietz syndrome, and 75.0% and 43.8% for vEDS, respectively. After a median (IQR) follow-up of 4.7 years (1.9-9.2), 91 patients (53.2%) had undergone secondary procedures, of which 14 (8.2%) were open conversions. Conclusions and Relevance: This study found that endovascular aortic interventions, including redo procedures and complex repairs of the aortic arch and visceral aorta, in patients with CTD had a high rate of early technical success, low perioperative mortality, and a midterm survival rate comparable with reports of open aortic surgery in patients with CTD. The rate of secondary procedures was high, but few patients required conversion to open repair. Improvements in devices and techniques, as well as ongoing follow-up, may result in endovascular treatment for patients with CTD being included in guideline recommendations.

A pilot study to evaluate a novel localized treatment to stabilize small- to medium-sized infrarenal abdominal aortic aneurysms.

OBJECTIVE: There is no proven therapy to reduce growth rates of small- to medium-sized abdominal aortic aneurysms (AAAs). Ex vivo and animal studies have demonstrated that a novel stabilizing agent, 1,2,3,4,6-pentagalloyl glucose (PGG), delivered locally to the aneurysm sac, can bind to elastin and collagen to re-establish strength and resist enzymatic degradation. We aimed to demonstrate that a one-time administration of PGG solution to the aneurysm wall is safe and potentially effective to slow the growth of small- to medium-sized AAAs. METHODS: Patients with small- to medium-sized infrarenal AAAs (maximum diameter <5.5 cm) were recruited. Via transfemoral access, a 14F or 16F dual-balloon delivery catheter was introduced into the aneurysm sac. A single, 3-minute, localized endoluminal infusion of PGG was delivered via a 'weeping' balloon to the aneurysm wall. Independent core laboratory measurements of maximum aneurysm sac diameter and sac volume measurements based on computed tomography angiography (CTA) were used for assessments at 1, 6, 12, 24, and 36 months. The primary endpoints were technical success and safety (major adverse events at 30 days). The secondary endpoint was growth stabilization, defined as freedom from aneurysm sac enlargement (diameter increase >5 mm per year or volume increase of >10% per year). RESULTS: Twenty patients (19 male) were enrolled at five centers from May 2019 to June 2022 (mean age, 67.8 years; range, 50-87 years). All procedures were technically successful. The safety profile was consistent with standard interventional procedures. Four patients demonstrated transient elevations of liver enzymes levels that returned to normal by 30 days with no clinical symptoms. Through November 2022, follow-up CTA data is available on the first 11 patients. The average changes in maximum aneurysm diameter from baseline to 6, 12, 24, and 36 months were 0.2 mm, 1.1 mm, 1.2 mm, and 0.8 mm, respectively, and the average changes in volume were 2.0%, 9.6%, 18.1%, and 11.6%, respectively. At 12 months, none of the aneurysms showed growth >5.0 mm, and three had volume growth >10%. CONCLUSIONS: The early results of this first-in-human, small cohort study demonstrated that a single, localized PGG administration to patients with small- to medium-sized infrarenal AAAs is safe. Longer term follow-up on all 20 treated patients is needed to better assess the potential impact on aneurysm growth.

Theoretical Feasibility of Using Arch Branched Endograft Devices for Repair of Post Type A Aortic Dissection in Patients With Prior Ascending Aortic Replacement.

PURPOSE: Ascending aortic replacement is a common emergency procedure for treating acute type A aortic dissection. Secondary open or endovascular interventions for residual arch pathologies is difficult because of adhesions, short prosthetic grafts, and distorted anatomies. Aortic arch branched stent grafts have emerged as a potential solution for these patients if they have suitable anatomical conditions. This study aimed to evaluate the theoretical anatomical and technical feasibility of 2 currently used aortic arch branch endografts in patients who had prior replacement of the ascending aorta. MATERIALS AND METHODS: All patients who had a prosthetic ascending aortic or hemiarch replacement for acute type A dissection in a single institution between January 2013 and December 2018 were included. Contrast computed tomography images on the most recent follow-up were analyzed on a 3-dimensional workstation. Morphological parameters were measured individually for the ascending aorta, aortic arch, supra-aortic branches, and access iliac arteries. The computed tomography scan of each patient was individually evaluated for anatomical suitability for the arch branched and double-branch devices according to set selection criteria. RESULTS: Computed tomography images of 56 patients (median age of 57 years, 45 males) were reviewed. Based on our evaluation, 26 patients (46.4%) were good candidates for an endovascular arch branched device. It would be feasible for 13 patients (23.2%), but prudent preoperative planning was required due to complicated anatomy. The other 17 patients (30.4%) were unsuitable because they met at least 1 exclusion criterion. Short prosthetic grafts, extreme graft angulations, and extensive dissections in the supra-aortic branches were the main reasons for exclusion. CONCLUSION: Endovascular repair using arch branched endografts is feasible in patients with prior ascending aortic arch or hemiarch replacement for acute type A aortic dissection. The most common anatomical conditions that may influence the feasibility of the arch branched endograft procedure include insufficient proximal seal length, severe angulation of the graft, and extensive aortic dissection within the supra-aortic vessels.

Not All Gymnastic Exercises Are Suitable for Everyone: An Uncommon Cause of Thoracic Outlet Syndrome: A Case Report.

CASE: A 34-year-old man spontaneously presented with bilateral thoracic outlet syndrome over 1 year. He was a gymnast active in rowing and weightlifting, with "slanted" shoulders, narrowed costoclavicular spaces, and well-developed scalene muscles. Imaging revealed fractures of multiple bilateral upper ribs in various degrees of nonunion. The patient's symptoms improved after activity modification and physiotherapy. CONCLUSIONS: Atraumatic spontaneous rib fracture-nonunions are an uncommon cause of thoracic outlet syndrome; this diagnosis should be considered in physically active patients presenting with typical symptoms with atypical anatomy.

Epidemiological updates of venous thromboembolism in a Chinese population.

BACKGROUND/OBJECTIVE: Deep vein thrombosis (DVT) was thought to be uncommon in Asians and routine thromboprophylaxis in the form of anticoagulation for surgical patients was considered to be unnecessary. The current study aims to provide a contemporary epidemiology of venous thromboembolism in a population-based scale. METHODS: Information from January 1, 2010 to December 31, 2011 was retrieved from a centralized computer public healthcare database serving mainly an ethnic Han Chinese population of 7.1 million. The incidence, demographics, and hospital mortality rates of DVT and pulmonary embolism (PE) were obtained, and analyzed for different surgical categories. RESULTS: The overall annual incidences of DVT, PE alone, and PE with DVT were 30.0 per 100,000 population, 8.7 per 100,000 population, and 3.0 per 100,000 population, respectively. Overall male to female ratio was 1:1.24. Venous thromboembolic disease was more common with increasing age in both sexes. Thirty days' mortality rates associated with DVT, PE alone, and PE with DVT were 9.0%, 17.4%, and 13.3% respectively. Among the patients who received 103,023 major and intermediate surgical procedures in the study period, the mean incidence of postoperative DVT, PE alone, and PE with DVT were only 0.20% (203.5 patients), 0.08% (85.5 patients), and 0.04% (40.5 patients) respectively. CONCLUSION: Compared with a similar study 10 years ago, there seemed to be a general increase in incidence of DVT and PE. This study showed that postoperative thromboembolic events were not uncommon, with DVT occurring in up to 0.2% of patients and PE in 0.12% of patients in this longitudinal survey.

New predictors of complications in carotid body tumor resection.

OBJECTIVE: This study examined the relationship between two new variables, tumor distance to base of skull (DTBOS) and tumor volume, with complications of carotid body tumor (CBT) resection, including bleeding and cranial nerve injury. METHODS: Patients who underwent CBT resection between 2004 and 2014 were studied using a standardized, multi-institutional database. Demographic, perioperative, and outcomes data were collected. CBT measurements were determined from computed tomography, magnetic resonance imaging, and ultrasound examination. RESULTS: There were 356 CBTs resected in 332 patients (mean age, 51 years; 72% female); 32% were classified as Shamblin I, 43% as Shamblin II, and 23% as Shamblin III. The mean DTBOS was 3.3 cm (standard deviation [SD], 2.1; range, 0-10), and the mean tumor volume was 209.7 cm3 (SD, 266.7; range, 1.1-1642.0 cm3). The mean estimated blood loss (EBL) was 257 mL (SD, 426; range, 0-3500 mL). Twenty-four percent of patients had cranial nerve injuries. The most common cranial nerves injured were the hypoglossal (10%), vagus (11%), and superior laryngeal (5%) nerves. Both Shamblin grade and DTBOS were statistically significantly correlated with EBL of surgery and cranial nerve injuries, whereas tumor volume was statistically significantly correlated with EBL. The logistic model for predicting blood loss and cranial nerve injury with all three variables-Shamblin, DTBOS, and volume (R2 = 0.171, 0.221, respectively)-was superior to a model with Shamblin alone (R2 = 0.043, 0.091, respectively). After adjusting for Shamblin grade and volume, every 1-cm decrease in DTBOS was associated with 1.8 times increase in risk of >250 mL of blood loss (95% confidence interval, 1.25-2.55) and 1.5 times increased risk of cranial nerve injury (95% confidence interval, 1.19-1.92). CONCLUSIONS: This large study of CBTs demonstrates the value of preoperatively determining tumor dimensions and how far the tumor is located from the base of the skull. DTBOS and tumor volume, when used in combination with the Shamblin grade, better predict bleeding and cranial nerve injury risk. Furthermore, surgical resection before expansion toward the base of the skull reduces complications as every 1-cm decrease in the distance to the skull base results in 1.8 times increase in >250 mL of blood loss and 1.5 times increased risk of cranial nerve injury.

Geometric Alteration of Renal Arteries After Fenestrated Grafting and the Impact on Renal Function.

BACKGROUND: This study aims to investigate the degree of geometric change on renal arteries and its impact on renal function after fenestrated endovascular aortic repair (fEVAR). METHODS: Twenty-five patients with fEVAR were included. There were 47 renal arteries target vessels, and 43 of these (22 left and 21 right vessels) stented successfully. Their preoperative and first postoperative follow-up computed tomography (CT) images were reconstructed using the Aquarius workstation (TeraRecon, San Mateo, CA, USA). The superior mesenteric artery (SMA) or celiac axis (if SMA was stented) was appointed as reference origin. The longitudinal orientation of a renal artery or a stent was represented by a takeoff angle (ToA) between the renal artery or stent and the distal abdominal aorta. The postoperative stent ToAs were compared with those of preoperative renal arteries. Preoperative and short-term postoperative serum creatinine levels were measured. Renal function impairment was indicated as a >30% or >2.0 mg/dL rise in serum creatinine compared to the preoperative level. The relationship between postoperative renal function impairment and the stent orientation or geometric changes in renal arteries was correlated. RESULTS: The patency rate of renal arteries was 100% at the first postoperative CT review. The average ToAs of both renal arteries were significantly enlarged after stenting (P < 0.05). Seven stent deformations (16.3%) in four patients (16.0%) were observed. They were attributed to caudal misalignment of the fenestrated stent graft (n = 6) or inaccurate graft sizing (n = 1). There was no stent fracture or target vessel loss. Postoperatively, nine patients (36.0%) at day 1 and 10 patients (41.7%) after 3 months suffered the renal function impairment. This was found not to be associated with the stent angulation or angular change of the renal arteries (both P > 0.05). The three patients with stent deformation due to misalignment suffered postoperative renal function impairment and continuing deterioration in renal function. CONCLUSIONS: Implanted renal stents could angulate renal arteries more cephalad after fenestrated stenting. Postoperative renal function impairment was not associated with the stent orientation and changes in vessel orientation. Accurate fenestrated alignment is important to maintain stent performance and preserve renal function.

Natural history and risk factors for rupture of thoracic aortic arch aneurysms.

OBJECTIVE: The management of degenerative aneurysms of the aortic arch requires careful selection of patients, taking into consideration risk of rupture and operative risks, which is more relevant with the emergence of hybrid debranching and branched and fenestrated endovascular options. The natural history of true arch aneurysms has not been previously studied. We aimed to determine the expansion rate of thoracic aortic arch aneurysm and to identify predictors for rupture. METHODS: Consecutive patients with known true thoracic aortic arch aneurysms monitored with serial computed tomography from 2000 to 2014 were retrospectively reviewed. Thoracoabdominal aneurysms and aneurysms due to aortic dissection and connective tissue diseases were excluded. Variables studied included patient demographics, aneurysm morphology, and ascending aorta diameter. A size expansion curve for each patient was plotted with serial computed tomography scan data, and the slope obtained by linear interpolation was taken as the expansion rate. Multiple logistic regression analysis was performed to identify independent predictors of rupture. Average yearly risks of rupture for overall and expansion rate substrata were calculated from life-table analysis. RESULTS: A total of 45 arch aneurysms were followed up for a mean of 36.6 months (3-104). Aneurysm growth was largely linear, with an average rate of 2.5 mm/y (0-16). During surveillance, 10 aneurysms ruptured (22%) and 8 patients died. There was one additional arch aneurysm-related death during follow-up, whereas 14 patients (31%) died of other causes. Aneurysms expanding at >5.5 mm/y have a 67% likelihood of rupture compared with 8.3% of those expanding at <5.5 mm/y. Aneurysm size >6.5 cm (P = .0001) and hyperlipidemia (P = .0321) were positively correlated with fast expansion. On univariate analysis, only aneurysm size and expansion rate were significant predictors of rupture. On multivariate analysis, aneurysm expansion rate was the sole independent risk factor of aneurysm rupture (odds ratio, 1.43; 95% confidence interval, 1.06-1.92; P = .018). CONCLUSIONS: Aneurysm expansion rate >5.5 mm/y is a significant rupture predictor in addition to size compared with aneurysm morphology and other demographic factors. Aneurysm size >6.5 mm and hyperlipidemia are determining factors of expansion rate. These may have implications in selection of patients for surgery. Better control of hyperlipidemia may alleviate the risk of rupture.

The compatibility of p-branch "off-the-shelf" fenestrated endovascular graft in Asian patients with juxtarenal aortic aneurysm.

OBJECTIVE: The Zenith pivot branch (p-branch) fenestrated endovascular graft (Cook Medical, Bloomington, Ind) is a new "off-the-shelf" device to treat patients with juxtarenal aortic aneurysms (JRAs). Two options are currently available, which appear to suit >70% of white patients. This study investigates the anatomic applicability of the p-branch fenestrated graft in a cohort of Asian patients with JRA. METHODS: Computed tomography images of 51 consecutive Asian patients with JRA (43 men; mean age, 76.8 years) were analyzed on an Aquarius workstation (TeraRecon, San Mateo, Calif) and matched to two current configurations of the p-branch (options A and B: single superior mesenteric artery [SMA] and two renal fenestrations, and a celiac axis scallop). With use of the SMA as reference, the anatomic positions of both renal arteries and the celiac axis were figured together with their diameters on a template generated on MATLAB (MathWorks, Natick, Mass), and then they were matched with two graft configurations. The renal artery origins were assessed for three classes of "closeness of fit" based on diameter: perfect match, marginal match, and mismatch, respectively, defined as the renal artery origins being located entirely inside, partially inside, and completely outside their corresponding fenestrations. The suitability of the p-branch graft design to the aneurysms was then evaluated. RESULTS: A total of 31 JRA patients (60.8%) were regarded as suitable candidates for one or both p-branch stent grafts (20 with option A, 22 with option B, and 11 with both options). In 35 patients (68.6%), both renal arteries could be aligned with the fenestrations. Among them, 16 patients (31.4%) were perfectly matched, whereas 19 patients (37.2%) were only marginally suitable. The major reason for exclusion was the misalignment of the renal fenestrations. In 16 patients with unsuitable renal fenestrations, 8 were attributed to the right renal origins being located too distally compared with their corresponding fenestrations. Another reason for exclusion was the position of the celiac axis scallop in four patients (7.84%), and insufficient aortic length for the graft was encountered in another four. If the right renal fenestration of option B was adjusted to 20 mm caudal to the SMA fenestration (level with the left fenestration), the match of renal fenestration could reach 78.4% (40 of 51). CONCLUSIONS: The present design of the p-branch off-the-shelf fenestrated graft is feasible for a good proportion of JRA patients in Asia. Further refinement of design may improve the anatomic match, especially a lower right renal artery origin.

Changes in inflammatory response after endovascular treatment for type B aortic dissection.

This present study aims to investigate the changes in the inflammatory markers after elective endovascular treatment of Type B aortic dissection with aneurysm, as related to different anatomical features of the dissection flap in the paravisceral perfusion. Consecutive patients with type B aortic dissections with elective endovascular stent graft repair were recruited and categorized into different groups. Serial plasma levels of cytokines (Interleukin-1ß, -6, -8, -10, TNF-α), chemokines (MCP-1), and serum creatinine were monitored at pre-, peri- and post-operative stages. The length of stent graft employed in each surgery was retrieved and correlated with the change of all studied biochemical parameters. A control group of aortic dissected patients with conventional medication management was recruited for comparing the baseline biochemical parameters. In total, 22 endovascular treated and 16 aortic dissected patients with surveillance were recruited. The endovascular treated patients had comparable baseline levels as the non-surgical patients. There was no immediate or thirty day-mortality, and none of the surgical patients developed post-operative mesenteric ischaemia or clinically significant renal impairment. All surgical patients had detectable pro-inflammatory mediators, but none of the them showed any statistical significant surge in the peri-operative period except IL-1ß and IL-6. Similar results were obtained when categorized into different groups. IL-1ß and IL-6 showed maximal levels within hours of the endovascular procedure (range, 3.93 to 27.3 higher than baseline; p = 0.001), but returned to baseline 1 day post-operatively. The change of IL-1ß and IL-6 at the stent graft deployment was statistically greater in longer stent graft (p>0.05). No significant changes were observed in the serum creatinine levels. In conclusion, elective endovascular repair of type B aortic dissection associated with insignificant changes in inflammatory mediators and creatinine. All levels fell toward basal levels post-operatively suggesting that thoracic endovascular aortic repair is rather less aggressive with insignificant inflammatory modulation.

Differential expression of sphingosine-1-phosphate receptors in abdominal aortic aneurysms.

OBJECTIVE: Inflammation plays a key role in the pathophysiology of abdominal aortic aneurysms (AAAs). Newly discovered Sphingosine-1-Phosphate Receptors (S1P receptors) are critical in modulating inflammatory response via prostaglandin production. The aim of the current study was to investigate the expression of different S1P receptors in AAAs and compared with normal aortas at the protein level. MATERIALS AND METHODS: Aortic specimens were harvested during aortic reconstructive surgery for the AAA group or during organ transplant for the control group. The protein expression of S1P1, 2 and 3 in AAAs and normal aortas was assessed by Western blotting and immunohistochemical analysis. RESULTS: There were 40 AAAs and 20 control aortas collected for the receptor analysis. For Western blot analysis, S1P1 expression was not detected in either group; S1P2 protein was constitutively detected in both types of aortas but its expression level was significantly decreased by 73% (P < 0.05) in AAAs compared with the control group. In contrast, strong S1P3 expression was detected in AAAs aortas but not in normal aortas. Immumohistochemical staining showed similar results, except a weak S1P3 signal was detectable in normal aortas. CONCLUSIONS: Western blot and staining results consistently showed the down-regulation of the S1P2 protein with simultaneous up-regulation of the S1P3 protein in AAAs. Since those newly discovered receptors play an important role in the inflammatory cascade, the modulating of S1P signaling, particularly via S1P2 and S1P3, could represent novel therapeutic targets in future AAA treatments.

A morphologic study of chronic type B aortic dissections and aneurysms after thoracic endovascular stent grafting.

BACKGROUND: The long-term results of treating chronic aortic dissections and aneurysms in association with dissections with thoracic endovascular aortic repair (TEVAR) are unknown, and the timing for intervention is uncertain. We evaluated the morphology of stent graft and aorta remodeling and the volumetric changes in these patients after successful TEVAR. METHODS: Serial computed tomography scans of 32 patients who underwent TEVAR for uncomplicated chronic dissections (group A, n = 17) and chronic dissections with aneurysms (group B, n = 15) were analyzed at 1, 6, 12, and 36 months. Stent graft diameter changes and positional migration were assessed three-dimensionally using Mimics 14.0 (Materialize, Leuven, Belgium). Volumetric data for true lumen, false lumen, thrombus load, and aortic size were measured by Aquarius iNtuition 4.4 software (TeraRecon, San Mateo, Calif). Results were compared between the two groups and with stent graft diameter, length, and oversizing. RESULTS: Aortic stent grafts remodeled progressively, with inlet area increasing 4.4%, 10.1%, and 14.2% and outlet area increasing 42.6%, 67.2%, and 72.3%, respectively, at 6, 12, and 36 months. True lumen volume increased progressively in group A (114 to 174 mL) and group B (124 to 190 mL) from baseline to 36 months. False lumen volume decreased in group A (150 to 88 mL) and group B (351 to 250 mL), whereas thrombus load in the false lumen increased from 73% to 80% in group A and 84% to 87% in group B in 3 years. Eight patients (4 in each group) showed an increase in total aortic volume of >10%, 12 showed a static volume, and 12 showed shrinkage. Aortic volume change had no relationship to pathology, stent graft sizing, and thrombus load but was positively associated with the placement of a longer graft. A small but progressive distal migration of stent grafts was noted in all patients (3.1, 4.5, and 5.1 mm at 6, 12, and 36 months) but was more prominent in shorter stent grafts (≤ 162 mm). No deaths, rupture, or secondary interventions occurred during follow-up. CONCLUSIONS: Aortic remodeling after TEVAR in chronic dissection is a continuous process. There were no significant differences between chronic dissections and aneurysms in all volumetric parameters. Treating chronic dissections early, before aneurysm formation, did not appear to have a morphologic advantage.

Surgeons' static posture and movement repetitions in open and laparoscopic surgery.

BACKGROUND: There is increasing concern about the surgeon maintaining a static posture during laparoscopic surgery, which can contribute to musculoskeletal disorders. A series of studies are being conducted in Hong Kong examining the surgeons' real-time movements and electromyography in the operating theater during different operations. The present paper examines the postures and movements of surgeons during real-time open and laparoscopic procedures. MATERIALS AND METHODS: Fourteen surgeons participated in the study (12 men, 2 women). Cervical spine movements were measured using a biaxial inclinometer attached to the surgeon's head via a headband. Biaxial electrogoniometers were attached to the surgeon's bilateral shoulder joints. Real-time joint movements in sagittal and coronal planes were recorded during open and laparoscopic surgeries for periods ranging from 30 to 80 min. RESULTS: Surgeons generally maintained a flexed neck posture during open surgery and a more extended neck posture during laparoscopic procedures. There were statistically significant differences in mean neck posture and mean left shoulder abduction posture between the two types of surgery. Laparoscopic procedures showed a trend for longer duration in static posture in the neck, while open procedures showed trends for higher frequencies of movements. CONCLUSIONS: This study presented a novel approach to quantify the physical workload of surgeons using biomechanical parameters to describe duration of static posture and repetitiveness of movements. Results showed that long durations of static postures in laparoscopic surgery were closely associated with low-level muscle tension, which may contribute to an increased risk of surgeons developing musculoskeletal disorders.

Differential expression of elastin assembly genes in patients with Stanford Type A aortic dissection using microarray analysis.

OBJECTIVE: Pathologic studies have demonstrated that aortic dissection is initiated by an intimal tear, followed by the rapid growth of an intramural hematoma that dissects the media and is characterized by elastin degradation. Genetic extracellular matrix abnormalities and proteinases may be the predisposing factors in aortic dissection, but little is known about the role of elastic fiber assembly. Fibulin-1 is an extracellular protein that is expressed in the vascular basement membrane. It regulates elastic fiber assembly and hence provides integrity in aortic structure. This study investigates the expression profiles of genes responsible for the elastolysis in the dissected human aorta, especially those coding fibulin-1, matrix metalloproteinase-9 (MMP-9), and elastin. METHODS: Intraoperative aortic samples were obtained from Chinese patients with Stanford Type A aortic dissection. Both the ascending dissected aortas (primary tear) and the adjacent intact aortas were collected for comparison. Control aortic tissues were obtained from healthy organ donors. The gene profile study was determined by the Affymetrix HG-U133A GeneChip (Affymetrix, Santa Clara, Calif) and analyzed by GeneSpring GX11.0 (Agilent Technologies Inc, Palo Alto, Calif). Only the genes displaying a net signal intensity two-fold higher than the mean background were used for analysis. To evaluate elastin expression, aortic sections were stained with Movat pentachrome stain. Fibulin-1, MMP-9, and elastin mRNA and protein expression were further confirmed by reverse transcriptase polymerase chain reaction (RT-PCR) and immunoblotting, respectively. RESULTS: Eight male Chinese aortic dissection patients (mean age, 45.8 years) and eight gender- and age-matched organ donors were recruited for the study. On the Affymetrix platform, 2,250 of 22,283 genes (10.1%) were detectable. The dissected and adjacent macroscopically intact aorta displayed similar gene expression patterns. In contrast, 11.2% (252) of the detectable genes were differentially expressed in the dissected and control aortas. Of these, 102 genes were upregulated, and 150 genes were downregulated. Based on the gene ontology, genes that code for extracellular matrix protein components and regulating elastic fiber assembly, like fibulin-1 and elastin, were downregulated, while enzymes like MMP-9 and MMP-11 that degrade matrix proteins were upregulated in dissected aortas. RT-PCR and Western blot results further validated the results. CONCLUSIONS: Our gender- and age-matched study demonstrated that the alternated genes in the elastin assembly of dissected aortas may predispose structural failure in the aorta leading to dissection. However, no significant gene alterations in the adjacent intact and dissected aortas of the same patient can be found. Therefore, the genetic changes found in the dissected aortas most likely developed before the dissection starts. The inhibition of the aberrant expression of the fibulin-1 gene and that of the related matrix proteinase may open a new avenue for preventing aortic dissection.