Endovascular Treatment of Superior Mesenteric Artery Pseudoaneurysm Due to Infective Endocarditis With Stent-Graft.

PURPOSE: To report a successful case of pseudoaneurysm of the superior mesenteric artery (SMA) caused by infected endocarditis treated with a covered stent. CASE REPORT: A patient was diagnosed with infective endocarditis and 2 months later a proximal SMA pseudoaneurysm was identified on computed tomography. Daptomycin was started on admission and continued for approximately 4 months until the inflammatory markers normalized, and then the SMA pseudoaneurysm was successfully excluded with a stent-graft and antibiotics were continued for 1 year after the procedure. There were no associated complications or recurrences at the 3-year follow-up. CONCLUSION: Placing a covered stent with a full course of antibiotics before and after surgery may be a successful alternative to open surgery in the treatment of pseudoaneurysms of the SMA due to infective endocarditis. CLINICAL IMPACT: This case report reports a rare case of pseudoaneurysm of the superior mesenteric artery due to infective endocarditis, which was successfully treated with an overlapping stent and confirmed by complete imaging data at a three-year follow-up. This report suggests that endovascular treatment may be an alternative to open surgery in the treatment of pseudoaneurysms of the superior mesenteric artery caused by infective endocarditis.

Acute Renal Infarction Due to Symptomatic Isolated Spontaneous Renal Artery Dissection: A Rare and Fatal Disease.

OBJECTIVE: To report demographics and clinical, laboratory, and imaging features of acute renal infarction (ARI) due to symptomatic isolated spontaneous renal artery dissection (SISRAD) and to analyze outcomes after the initial therapy for SISRAD. METHODS: Thirteen patients with ARI due to SISRAD between January 2016 and March 2021 were enrolled in this retrospective study. We reviewed the demographics, clinical, laboratory, and imaging features (location of the infarct kidney, the branch artery involved by dissection, true lumen stenosis, false lumen thrombosis, and aneurysm), treatment modalities, and follow-up results; analyzed the difference between SISRAD and other causes of ARI; and propose an appropriate therapy strategy for SISRAD based on our data and literature. RESULT: Patients with ARI due to SISRAD were mostly young men (43 [24-53] years; 12/13 [92%]). No patients had atrial fibrillation or acute kidney injury at admission (0/13). All 13 patients received conservative treatment as the initial treatment. Sixty-two percent (8/13) of patients progressed, and 88% (7/8) of them had dissection aneurysm on the admission computed tomographic angiography (CTA) image. Seventy-five percent (6/8) of patients underwent endovascular intervention as follows, stent placement in 1 patient, renal artery embolization in 1, and stent placement with embolization in 4. Two patients with disease progression died: 1 during the conservative treatment period and 1 after the stent placement. Thirty-eight percent (5/13) of patients in remission continued to receive conservative treatment, none of whom had dissection aneurysm on the admission CTA. CONCLUSION: Symptomatic isolated spontaneous renal artery dissection is a rare and fatal disease. For young ARI patients with no previous history of tumors and cardiogenic diseases, CTA examination is recommended to exclude SISRAD. Dissection aneurysm seems to be a risk of progression for SISRAD in this series. Conservative treatment, a recognized initial treatment, has a good effect on patients without dissection aneurysm, and we recommend endovascular intervention as the initial treatment for the patient with dissection aneurysm at admission. Multicenter clinical studies are needed to explore a more-appropriate treatment for patients with SISRAD. CLINICAL IMPACT: This article report the related factors, risks, demographics and laboratory data of Acute renal infarction (ARI) due to Symptomatic isolated spontaneous renal artery dissection (SISRAD) and explore a better initial therapy strategy for SISRAD. It will help improve the effectiveness of SISRAD treatment and reduce the mortality rate from this rare but lethal disease.

Mid-term Outcomes of Physician-Modified Fenestrated or Branched Endovascular Repair for Post-dissection Thoracoabdominal Aortic Aneurysms.

PURPOSE: To report the early experience and mid-term outcomes of physician-modified fenestrated or branched endovascular repair (PM-F/BEVAR) for patients with post-dissection thoracoabdominal aortic aneurysm (PD-TAAA). METHODS: PD-TAAA patients treated with PM-F/BEVAR between December 2014 and September 2020 in our institution were retrospectively analyzed. RESULTS: Out of the 39 patients, technical success defined as successful deployment of all stent grafts with patent target vessels (TVs) and exclusion of the lesion without type I or III endoleak was achieved in 35 patients (89.7%). A total of 126 TVs were successfully reconstructed. Thirty-day mortality was 0%. Seven major adverse events occurred including one acute kidney injury, four renal infarctions, one retroperitoneal hematoma and one left renal artery occlusion. Seven type II endoleak and three type III endoleak were detected. During a mean 29.4 ± 15.5 months follow-up period, the mortality was zero. Three renal arteries and one external iliac artery occluded in four patients. No other new onset major adverse event occurred. No patient required reintervention. One type II endoleak spontaneously resolved, while the remaining six remained stable. One early type III endoleak diminished, and one new type III endoleak occurred at 2 months. The primary patency of TV was 96.8% (120/124). Shrinkage or stability of aneurysm diameter can be observed in 38 patients (97.4%). The false lumen thrombosis rate was 89.7% (35/39). CONCLUSIONS: The present study showed encouraging results of PM-F/BEVAR for treatment of PD-TAAAs. LEVEL OF EVIDENCE: Level 4, Case Series.

Improving Breast Tumor Segmentation in PET via Attentive Transformation Based Normalization.

Positron Emission Tomography (PET) has become a preferred imaging modality for cancer diagnosis, radiotherapy planning, and treatment responses monitoring. Accurate and automatic tumor segmentation is the fundamental requirement for these clinical applications. Deep convolutional neural networks have become the state-of-the-art in PET tumor segmentation. The normalization process is one of the key components for accelerating network training and improving the performance of the network. However, existing normalization methods either introduce batch noise into the instance PET image by calculating statistics on batch level or introduce background noise into every single pixel by sharing the same learnable parameters spatially. In this paper, we proposed an attentive transformation (AT)-based normalization method for PET tumor segmentation. We exploit the distinguishability of breast tumor in PET images and dynamically generate dedicated and pixel-dependent learnable parameters in normalization via the transformation on a combination of channel-wise and spatial-wise attentive responses. The attentive learnable parameters allow to re-calibrate features pixel-by-pixel to focus on the high-uptake area while attenuating the background noise of PET images. Our experimental results on two real clinical datasets show that the AT-based normalization method improves breast tumor segmentation performance when compared with the existing normalization methods.

Experimental Analysis of In Situ Fenestration of Endovascular Stent-Grafts: Comparison between Needle and Laser Puncture.

BACKGROUND: To evaluate the quality of in vitro fenestrations during in situ fenestration (ISF) and investigate the differences between needle and laser puncture in current stent-grafts. METHODS: An in vitro study evaluated the damage created by needle ISF on stent-graft fabrics versus laser ISF. Fenestrations were made in 5 different commercially available stent-grafts, including polyester stent-grafts (Relay, Valiant and Hercules) and expanded polytetrafluoroethylene (ePTFE) stent-grafts (TAG and Ankura). Each stent-graft received fenestration by needle and laser separately, followed by gradual dilation (4 mm, 6 mm, 8 mm, and 10 mm sequentially) of noncompliant balloons. Quantitative and qualitative evaluations including fenestration diameter, area, shape and margins were conducted using light microscopy and scanning electron microscope. RESULTS: The primary fenestrations created by needle were slit-like with visible cut-off fibers in polyester stent-grafts and were almost circular with clear margins in ePTFE stent-grafts; those created by laser were squared or elliptical with ragged edges and burned fibers in all the stent-grafts. Fabric debris and toxic particles due to burning of the material were generated during laser-assisted fenestration. The Primary holes in polyester stent-grafts (Relay, Valiant and Hercules) by needle showed smaller area (0.05 mm2 vs. 0.22 mm2, 0.52 mm2 vs. 0.70 mm2 and 0.28 mm2 vs. 0.46 mm2; P < 0.01) and worse shape (0.93 vs. 2.46, 1.17 vs. 2.33 and 0.93 vs. 2.47; P < 0.01) than those by laser, while larger area (0.67 vs.0.43, 0.59 vs.0.45; P < 0.05), better shape (3.93 vs. 2.53, 3.90 vs. 2.93; P < 0.05) and better margin (3.83 vs. 2.47, 3.83 vs. 2.53; P < 0.05) in ePTFE stent-grafts (TAG and Ankrura). After gradual balloon dilation, the final holes showed no evident difference in maximal length, fenestration area, scores of shape and margin between the 2 ways of fenestration (P > 0.05). Ankura stent-graft showed the largest holes with best quality than the others. CONCLUSIONS: The primary fenestrations were different between needle and laser puncture, laser induced fabric debris and toxic particles release should be cautiously considered. The final fenestrations were similar after gradual balloon dilation.

Experimental Analysis of the Quality of Needle-Assisted Fenestration in Aortic Stent-Grafts and the Differences Between Gradual and Rapid Balloon Dilation.

Purpose: To report the findings of an in vitro experiment to evaluate the quality of needle fenestrations dilated by different size balloons in various stent-grafts and to investigate the differences between gradual and rapid dilation. Materials and Methods: Fenestrations were made using an 18-G needle in 5 different polyester or expanded polytetrafluoroethylene (ePTFE) stent-grafts: Relay, Valiant, Hercules, TAG, and Ankura. Each stent-graft received 2 groups of fenestrations: one was followed by gradual sequential dilation (4-, 6-, 8-, and 10-mm balloons) and the other by rapid dilation (4- and 10-mm balloons). The pressure was increased to 10 atmospheres or until the balloon was fully inflated with no waist. Quantitative and qualitative evaluations, including fenestration diameter, area, shape, and margins were conducted using light microscopy and scanning electron microscopy. Results: Relay had the strongest resistance to dilation and Ankura the slightest. The maximum length and area of holes expanded as the balloon diameter increased. The fenestrations in polyester devices were mostly elliptical or slit-like, with limited tears but extensive fibers visible in the margin, while ePTFE stent-grafts showed larger fenestration areas with clearer margins. Ankura showed the best quality of fenestrations, which were always circular or square without fabric tears, while the holes in the TAG were square or elliptical but sometimes had a slit after large balloon dilation (≥6 mm). The Relay, Valiant, Hercules, and Ankura devices showed no difference in maximum diameter, fenestration area, or scores of shape and margin (p>0.05). Rapid dilation in the TAG increased the rate of uncontrolled fabric tear, resulting in a larger final diameter (12.90 vs 10.82 mm, p=0.047), smaller area (30.46 vs 41.09 mm2, p=0.028), worse shape (0.75 vs 1.20, p=0.268), and worse margin (0.40 vs 1.00, p=0.174). Though the decreased fenestration shape and margin scores did not reach statistical significance, the trend for decline was more obvious than with the other devices. Conclusion: Materials and structures of the stent-grafts determine the quality of fenestrations dilated by different size balloons. The use of sequential vs rapid balloon dilation is also crucial for fashioning high-quality fenestrations and should be selected judiciously.

Identification of Serum Biomarker in Acute Aortic Dissection by Global and Targeted Metabolomics.

BACKGROUND: Acute aortic dissection (AAD) is the most devastating aortic pathology, and the incidence is increasing worldwide. However, the occurrence and development of AAD are unpredictable. A thorough understanding of the serum metabolic landscape through metabolomic analysis may help identify new biomarkers for AAD and offers new insights into its prevention and evaluation. METHODS: Nineteen patients with Stanford type A aortic dissection and 20 healthy individuals were enrolled in this study. We use global and targeted mass spectrometry-based metabolomics to investigate the serum metabolomics profiles, and the data were analyzed by principal component analysis and orthogonal partial least squares discriminant analysis. RESULTS: Initial untargeted metabolomics analysis revealed significant changes of lipids and polar metabolites in patients with AAD. Alterations of the phosphatidylcholine metabolic pathway were further observed by targeted metabolomics. Trimethylamine N-oxide (TMAO) levels were obviously increased in patients with AAD compared with controls (P < 0.005), whereas the levels of carnitine (P < 0.005), choline, and betaine (P < 0.05) were decreased. Furthermore, TMAO levels were associated with disease severity in AAD and correlated positively with C-reactive protein levels (r = 0.537, P = 0.018), IL-6 levels (r = 0.546, P = 0.016), D-dimer levels (r = 0.694, P = 0.001), and maximum aortic diameter on admission (r = 0.748, P = 0.002). CONCLUSIONS: Patients with AAD showed a predominant and consistent change of metabolites levels, especially the compounds in the phosphatidylcholine metabolic pathway. TMAO could potentially serve as a biomarker for the auxiliary diagnosis and evaluation of AAD.

Band bending of TiO2 induced by O-xylene and acetaldehyde adsorption and its effect on the generation of active radicals.

Most studies on the photodegradation of volatile organic compounds (VOCs) have focused on the synthesis of efficient photocatalysts. However, little attention has been paid to the band bending change of semiconductive photocatalysts after the adsorption of VOCs. Herein, we first disclose how the adsorption of two typical VOCs influences the band bending of P-type rutile TiO2 and consequently changes the amount of reactive radicals. This provides a new way to understand the experimental phenomenon of heterogeneous reactions. Theoretical computations of the adsorption model and zeta potential tests both verified that o-xylene is an acceptor molecule when it adsorbs on the TiO2 surface, and it tends to attract electrons from TiO2. In contrast, acetaldehyde is a donor molecule. A distinct electron transfer direction between TiO2 and adsorbed molecules (o-xylene and acetaldehyde) induces a different band bending degree. O-xylene adsorption alleviates the downward band bending of TiO2 itself, whereas acetaldehyde adsorption strengthens the downward band bending. The probability of electrons and holes reaching the TiO2 surface is influenced by this change, which has a considerable influence on the generation of active radicals. Consequently, o-xylene adsorption leads to more hydroxyl radical generation, and acetaldehyde adsorption results in less hydroxyl radical generation. As a result, hydroxyl radicals play the predominant role in the degradation of o-xylene, whereas the photocatalysis of acetaldehyde is dominant for superoxide radicals. In addition, the band bending of a semiconductor induced by gaseous molecule adsorption has the potential for application in gas sensors to improve sensitivity.

Long non-coding RNA GAPLINC promotes angiogenesis by regulating miR-211 under hypoxia in human umbilical vein endothelial cells.

In this study, we investigated the role of a long non-coding RNA GAPLINC in angiogenesis using human umbilical vein endothelial cells (HUVEC). We found that hypoxia and hypoxia-inducible factor 1α (HIF-1α) increased the expression of GAPLINC in HUVEC cells. Moreover, GAPLINC overexpression down-regulated miR-211 and up-regulated Bcl2 protein expression. Further rescue experiments confirmed that hypoxia directly increased GAPLINC expression. GAPLINC overexpression also increased cell migration and vessel formation which promoted angiogenesis, and these changes were attributed to the increased expression of vascular endothelial growth factor receptors (VEGFR) and delta-like canonical notch ligand 4 (DLL4) receptors. Finally, we demonstrated that GAPLINC promotes vessel formation and migration by regulating MAPK and NF-kB signalling pathways. Taken together, these findings comprehensively demonstrate that overexpression of GAPLINC increases HUVEC cells angiogenesis under hypoxia condition suggesting that GAPLINC can be a potential target for critical limb ischaemia (CLI) treatment.

New insights into the synergistic effect of active radicals and adsorptive ability on the photodegradation of gaseous acetaldehyde over reduced graphene Oxide/P25 composite.

Although coupling reduced graphene oxide (RGO) with TiO2 is believed to enhance the photocatalysis through the light utilization, studies on its photothermal conversion effect are rarely reported. Herein, RGOP (reduced graphene oxide/P25) was synthesized to explore roles of the enhanced light adsorption and photothermal conversion in the photocatalytic process. It was found that although RGOP had increased absorbance, it actually possessed lower available light utilization compared with P25. In the synergistic effect of available light utilization, transfer resistance and hydrophilicity, RGOP exhibited less superoxide radicals but more hydroxyl radicals. In the presence of scavenger experiments, O2- was proved to play the predominant role in the photocatalytic process, while OH was the secondary one. In comparison to P25, the change of active radicals of RGOP was adverse to its photocatalysis. However, due to the superior adsorptive property of RGOP, it exhibited higher photocatalytic activity than P25. The improved photocatalytic activity of RGOP was ascribed to its superior adsorptive ability aside from active radicals (O2-, OH).

Neutral models of short-term microbiome dynamics with host subpopulation structure and migration limitation.

BACKGROUND: Most empirical studies tend to focus on microbiome dynamics within hosts or microbiome compositional differences between hosts over short periods. However, there is still a dearth of formal models that allow us to investigate the observed short-term dynamics of microbiomes under a unified ecological and evolutionary framework. In our previous study, we developed a computational agent-based neutral framework that simulates microbiome dynamics spanning many host generations with the added dimension of a genealogy of hosts. Although this long-term framework revealed interesting microbial diversity patterns under a simple but plausible evolutionary process and provided a platform for future elaboration of more complex systems, it does not allow us to explore microbiome dynamics within a single host generation. METHODS: In this paper, we developed a computational, agent-based, forward-time framework of microbiome dynamics within a single host generation. As we have done under our neutral long-term models, we incorporate neutral processes of environmental microbiome assembly and microbe acquisition from parents and environment. We also incorporate a Moran genealogical model of hosts, so that the dynamics of microbiome evolution can be studied within a single host generation. Furthermore, we allow host subpopulation structure and host migration to affect microbiome recruitment. RESULTS: We show that microbiome diversity within hosts increases monotonically with increases in environmental contribution, while microbiome diversity between hosts increases with increasing parental inheritance. Host population division and dispersal limitation under high host contribution further shaped the patterns by elevating microbiome differences between hosts and depressing microbial diversity within hosts. Microbiome diversity within the whole population showed strong temporal stability regardless of the modes of microbiome acquisition and subpopulation structures. CONCLUSIONS: We present a computational framework that integrates various processes including host genealogy, microbe recruitment, and host dispersal limitation acting on the short-term dynamics of microbiomes. Our framework demonstrates that the neutral dynamics of microbiomes within a population of hosts is strongly influenced by transmission mode and shared environment.

Models of microbiome evolution incorporating host and microbial selection.

BACKGROUND: Numerous empirical studies suggest that hosts and microbes exert reciprocal selective effects on their ecological partners. Nonetheless, we still lack an explicit framework to model the dynamics of both hosts and microbes under selection. In a previous study, we developed an agent-based forward-time computational framework to simulate the neutral evolution of host-associated microbial communities in a constant-sized, unstructured population of hosts. These neutral models allowed offspring to sample microbes randomly from parents and/or from the environment. Additionally, the environmental pool of available microbes was constituted by fixed and persistent microbial OTUs and by contributions from host individuals in the preceding generation. METHODS: In this paper, we extend our neutral models to allow selection to operate on both hosts and microbes. We do this by constructing a phenome for each microbial OTU consisting of a sample of traits that influence host and microbial fitnesses independently. Microbial traits can influence the fitness of hosts ("host selection") and the fitness of microbes ("trait-mediated microbial selection"). Additionally, the fitness effects of traits on microbes can be modified by their hosts ("host-mediated microbial selection"). We simulate the effects of these three types of selection, individually or in combination, on microbiome diversities and the fitnesses of hosts and microbes over several thousand generations of hosts. RESULTS: We show that microbiome diversity is strongly influenced by selection acting on microbes. Selection acting on hosts only influences microbiome diversity when there is near-complete direct or indirect parental contribution to the microbiomes of offspring. Unsurprisingly, microbial fitness increases under microbial selection. Interestingly, when host selection operates, host fitness only increases under two conditions: (1) when there is a strong parental contribution to microbial communities or (2) in the absence of a strong parental contribution, when host-mediated selection acts on microbes concomitantly. CONCLUSIONS: We present a computational framework that integrates different selective processes acting on the evolution of microbiomes. Our framework demonstrates that selection acting on microbes can have a strong effect on microbial diversities and fitnesses, whereas selection on hosts can have weaker outcomes.

Single-center experience with simultaneous thoracic endovascular aortic repair and abdominal endovascular aneurysm repair.

Objective To evaluate the efficacy and outcomes of simultaneous thoracic endovascular aortic repair (TEVAR) and abdominal endovascular aneurysm repair (EVAR). Methods A total of 21 patients (20 men; mean 65 ± 7 years, range 54-77) underwent simultaneous TEVAR and EVAR between September 2010 and June 2015 at a single center were retrospectively reviewed. All patients had concomitant thoracic pathologies (aneurysm, penetrating aortic ulcer, intramural hematoma, or dissection) and abdominal aortic aneurysm. The abdominal aneurysms diameters ranged from 5.9 cm to 10 cm. Thoracic lesions in 17 patients were complicated with acute aortic syndrome, and the remainders had indications for simultaneous repair. All patients were followed up postoperative at 1 month, 6 months, and yearly thereafter. Technique success, procedure-related complications were evaluated. Results All patients received local anesthesia, perioperative relative high arterial pressure (above 130/80 mmHg) maintenance, and prophylactic high-dose corticosteroid. The technical success rate was 100%. Average procedural time was 157.6 ± 45.6 min. The length of thoracic coverage was 20.4 ± 4.7 cm (range 15-27). Two patients required left subclavian artery coverage during TEVAR and two patients required lowest renal artery coverage during EVAR. Chimney stents were deployed simultaneously. Patients were followed between 2 and 59 months postoperatively. No patients developed acute cardiopulmonary complications and contrast-induced nephropathy. Two patients developed transient lower extremity weakness that resolved with blood pressure elevation, cerebrospinal fluid drainage, and intravenous drips of high-dose corticosteroid. The average hospital stay was 10.7 ± 7.9 days (range 4-30). During follow-up, one patient died of aneurysm rupture at postoperative 6 months, two patients developed type Ib endoleak at 9 months and 48 months respectively, one was successfully sealed with iliac stent-graft extension, the other received conservative treatment and is symptom free till now. Conclusion Combined TEVAR and EVAR can be performed safely with minimal morbidity and mortality. When anatomically feasible, simultaneous TEVAR and EVAR can be considered as an acceptable alternative for multilevel aortic diseases.

Neutral Models of Microbiome Evolution.

There has been an explosion of research on host-associated microbial communities (i.e.,microbiomes). Much of this research has focused on surveys of microbial diversities across a variety of host species, including humans, with a view to understanding how these microbiomes are distributed across space and time, and how they correlate with host health, disease, phenotype, physiology and ecology. Fewer studies have focused on how these microbiomes may have evolved. In this paper, we develop an agent-based framework to study the dynamics of microbiome evolution. Our framework incorporates neutral models of how hosts acquire their microbiomes, and how the environmental microbial community that is available to the hosts is assembled. Most importantly, our framework also incorporates a Wright-Fisher genealogical model of hosts, so that the dynamics of microbiome evolution is studied on an evolutionary timescale. Our results indicate that the extent of parental contribution to microbial availability from one generation to the next significantly impacts the diversity of microbiomes: the greater the parental contribution, the less diverse the microbiomes. In contrast, even when there is only a very small contribution from a constant environmental pool, microbial communities can remain highly diverse. Finally, we show that our models may be used to construct hypotheses about the types of processes that operate to assemble microbiomes over evolutionary time.

Endovascular repair of Stanford B aortic dissection using two stent grafts with different sizes.

OBJECTIVE: The objective of this study was to introduce a novel strategy for thoracic endovascular aortic repair of Stanford B aortic dissection using two-stent graft implantation (TSI), in which the proximal stent and distal stent with different sizes are sequentially deployed, and to summarize our experience with this technique. METHODS: A retrospective study was conducted of 72 consecutive patients (61 men; mean age, 55 ± 7 years; range, 41-67 years) with Stanford type B aortic dissection who underwent TSI treatment between January 2012 and May 2013. Among all patients, 43 (59.7%) involved the infrarenal aorta and 29 (40.3%) involved the whole thoracic and abdominal aorta; mean aortic involvement length was 226 ± 13 mm (range, 182-312 mm). Eight cases were for acute dissection (within 2 weeks from onset of symptoms), 11 cases were for chronic dissection (>3 months after initial dissection), and 53 cases were for subacute dissection (between 2 weeks and 3 months). Twenty-two cases (30.6%) were uncomplicated type and 50 cases (69.4%) were complicated type. Follow-up was performed postoperatively at 1 month, 6 months, and yearly thereafter. Technique success, aorta morphology, and procedure-related complications were evaluated. RESULTS: Technical success was achieved in 100%; 72 pairs of stent grafts (144 thoracic stent grafts) and 10 left subclavian artery chimney stents were used. The mean aortic length coverage by the stent grafts was 197.6 ± 20.3 mm, and mean taper diameter span was 7.5 ± 1.8 mm. All patients were followed up from 6 to 16 months (mean, 10 ± 4 months); 95.8% (69 of 72) had a thrombosed false lumen in the aortic coverage, and the true lumen expanded on average 57% ± 11% (23%-100%). No significant changes were found in aortic diameters of the proximal and distal ends of the two stent grafts and the angles between centerlines of the distal end of the stent and the aorta during follow-up. Procedure-related complications included transient paraplegia (coverage of the left subclavian artery without revascularization and extensive coverage of aorta >220 mm) due to acute spinal cord ischemia (n = 1) and malapposition of the distal stent (primary tear closed, true lumen expansion led to oversize rate insufficient in distal stent diameter; n = 1). No death or malperfusion complications were observed during the perioperative period and follow-up. CONCLUSIONS: Short-term outcomes showed TSI to be a flexible and effective approach to accurately repair Stanford B aortic dissection that could potentially address the limitations of currently available stent grafts. Further prospective clinical studies are warranted to evaluate its long-term efficacy.

Endovascular repair of abdominal aortic aneurysm with severely angulated neck and tortuous artery access: case report and literature review.

BACKGROUND: Endovascular aneurysm repair has revolutionized the therapeutic strategy for abdominal aortic aneurysm. However, hostile proximal aneurysmal neck and tortuosity of access vessels remain challenges in selecting optimal stent-grafts in abdominal aortic aneurysms with difficult anatomy. CASE PRESENTATION: A 65-year-old woman complained of intermittent abdominal pain for one week. Computed tomography angiogram demonstrated a tortuous infrarenal abdominal aortic aneurysm with a tapered neck and a 136° of infrarenal angulation. Aneurysmal dilatation and severe calcification of bilateral iliac arteries and tortuous aortoiliac access were also showed. Endovascular approach using Endurant stent-graft was attempted at an outside hospital, but failed because of the significant tortuosity of the abdominal aorta and iliac arteries. Since the patient refused to have open aneurysm repair, he was transferred to our hospital for further evaluation and possible EVAR with a different approach. EVAR was performed successfully using Gore Excluder stent-grafts (W.L. Gore & Associates, Flagstaff, AZ, USA). During the procedure, cannulation of the contralateral limb was unable to be achieved because of the tortuous aortoiliac course. Therefore, a snare was inserted from right radial artery, through the contralateral gate, to grasp the wire from left femoral artery. Two iliac stent-grafts were sequentially deployed with the lower end distal to the opening of the left internal iliac artery. Angiography confirmed complete sealing of the aneurysm with patency of bilateral renal arteries and external iliac arteries. The postoperative courses were uneventful and follow-up computed tomography angiogram at 6 months demonstrated patent bilateral femoral and renal arteries without endoleaks or stent migration. CONCLUSION: Although endovascular repair of aortic aneurysm with hostile neck and tortuous access is rather challenging, choosing flexible stent-grafts and suitable techniques is able to achieve an encouraging outcome.