Crosstalk of platelets with macrophages and fibroblasts aggravates inflammation, aortic wall stiffening, and osteopontin release in abdominal aortic aneurysm

AIMS

Abdominal aortic aneurysm (AAA) is a highly lethal disease with progressive dilatation of the abdominal aorta accompanied by degradation and remodelling of the vessel wall due to chronic inflammation. Platelets play an important role in cardiovascular diseases, but their role in AAA is poorly understood.

METHODS AND RESULTS

The present study revealed that platelets play a crucial role in promoting AAA through modulation of inflammation and degradation of the extracellular matrix (ECM). They are responsible for the up-regulation of SPP1 (osteopontin, OPN) gene expression in macrophages and aortic tissue, which triggers inflammation and remodelling and also platelet adhesion and migration into the abdominal aortic wall and the intraluminal thrombus (ILT). Further, enhanced platelet activation and pro-coagulant activity result in elevated gene expression of various cytokines, Mmp9 and Col1a1 in macrophages and Il-6 and Mmp9 in fibroblasts. Enhanced platelet activation and pro-coagulant activity were also detected in AAA patients. Further, we detected platelets and OPN in the vessel wall and in the ILT of patients who underwent open repair of AAA. Platelet depletion in experimental murine AAA reduced inflammation and ECM remodelling, with reduced elastin fragmentation and aortic diameter expansion. Of note, OPN co-localized with platelets, suggesting a potential role of OPN for the recruitment of platelets into the ILT and the aortic wall.

CONCLUSION

In conclusion, our data strongly support the potential relevance of anti-platelet therapy to reduce AAA progression and rupture in AAA patients.

Angiotensin Receptor-Neprilysin Inhibition (Sacubitril/Valsartan) Reduces Structural Arterial Stiffness in Middle-Aged Mice

BACKGROUND

Increasing arterial stiffness is a prominent feature of the aging cardiovascular system. Arterial stiffening leads to fundamental alterations in central hemodynamics with widespread detrimental implications for organ function resulting in significant morbidity and death, and specific therapies to address the underlying age-related structural arterial remodeling remain elusive. The present study investigates the potential of the recently clinically available dual angiotensin receptor-neprilysin inhibitor (ARNI) sacubitril/valsartan (LCZ696) to counteract age-related arterial fibrotic remodeling and stiffening in 1-year-old mice.

METHODS AND RESULTS

Treatment of in 1-year-old mice with ARNI (sacubitril/valsartan), in contrast to angiotensin receptor blocker monotherapy (valsartan) and vehicle treatment (controls), significantly decreases structural aortic stiffness (as measured by in vivo pulse-wave velocity and ex vivo aortic pressure myography). This phenomenon appears, at least partly, independent of (indirect) blood pressure effects and may be related to a direct antifibrotic interference with aortic smooth muscle cell collagen production. Furthermore, we find aortic remodeling and destiffening due to ARNI treatment to be associated with improved parameters of cardiac diastolic function in aged mice.

CONCLUSIONS

This study provides preclinical mechanistic evidence indicating that ARNI-based interventions may counteract age-related arterial stiffening and may therefore be further investigated as a promising strategy to improve cardiovascular outcomes in the elderly.

Analysis of Determinants for Suture-mediated Closure Device Failure During EVAR Procedures

OBJECTIVE

Endovascular aortic repair (EVAR) for elective and emergency infrarenal aortic pathologies is the primary approach for treatment nowadays. During such procedure, the suture-mediated closure device (SMCD) (Perclose ProGlideTM, Abbott Laboratories, Chicago, IL, USA) is commonly used. This study aimed to identify potential contributors for SMCD failure in a patient cohort of elective and emergency EVAR.

METHODS

Archived medical records from patients who underwent EVAR for aortic pathologies in elective and emergency setting at the University Hospital Düsseldorf, Germany were included. Patient's co-morbidities, access vessel morphologies and hemostasis-related blood parameters were evaluated on their association with SMCD failure applying different statistical methods.

RESULTS

A total of 71 patients (139 femoral accesses) was included. The mean age was 73.5 ± 8.4 years. Overall SMCD failure rate was 4.3%, 4.1% for elective and 5.9% for emergency cases, respectively. Total procedure time was longer for the SMCD failure group (323 ± 117.8 min vs 171 ± 43.7 min). The calcification status of the common femoral artery (CFA), the diameter of the aortic bifurcation, and dual anti-platelet therapy (DAPT) on the medication plan prior to the procedure were associated with SMCD failure. Univariate binary logistic regression analysis nominated several potentially relevant predictors for SMCD failure who underwent subsequent multivariable binary logistic regression analysis. Here, DAPT on the medication plan was identified as being promising in predicting SMCD failure (OR 30.5), while anterior plaque formation in the CFA maintained as only statistically relevant determinant (OR 44.9).

CONCLUSIONS

This study confirms the CFA calcification status to be associated with SMCD failure. Although discontinued prior to endovascular treatment, DAPT was also found to be associated with SMCD failure. Our results may advocate to perform obligatory platelet testing prior to EVAR to maximize patient safety.

Abdominal Aortic Endograft Implantation Immediately Induces Vascular Stiffness Gradients That May Promote Adverse Aortic Neck Dilatation: Results of A Porcine Ex Vivo Study

PURPOSE

Endovascular aortic repair (EVAR) is the method of choice for most abdominal aortic aneurysm (AAA) patients requiring intervention. However, chronic aortic neck dilatation (AND) following EVAR progressively weakens the structural seal between vessel and endograft and compromises long-term results of the therapy. This experimental ex vivo study seeks to investigate mechanisms of AND.

MATERIALS AND METHODS

Porcine abdominal aortas (n=20) were harvested from slaughterhouse pigs and connected to a mock circulation. A commercially available endograft was implanted (n=10) or aortas were left untreated as controls (n=10). Vascular circumferential strain was assessed via ultrasound in defined aortic segments as a parameter of aortic stiffness. Histology and aortic gene expression analysis were performed to investigate potential changes of aortic wall structure and molecular differences due to endograft implantation.

RESULTS

We found that endograft implantation acutely induces a significant stiffness gradient directly at the interface between stented and unstented aortic segments under pulsatile pressure. Comparing stented aortas with unstented controls, we detected increased aortic expression levels of inflammatory cytokines (Il6 and Ccl2) and matrix metalloproteinases (Mmp2 and Mmp9) after 6 hours of pulsatile pressurization. This effect, however, was abolished when repeating the same experiment under 6 hours of static pressure.

CONCLUSIONS

We identified endograft-induced aortic stiffness gradients as an early trigger of inflammatory aortic remodeling processes that might promote AND. These results highlight the importance of adequate endograft designs to minimize vascular stiffness gradients and forestall late complications, such as AND.

CLINICAL IMPACT

AND may compromise the long-term results following endovascular aortic repair. However, the mechanisms behind the underlying detrimental aortic remodeling are still unclear. In this study we find that endograft-induced aortic stiffness gradients induce an inflammatory aortic remodeling response consistent with AND. This novel pathomechanistic insight may guide the design of new aortic endografts that minimize vascular stiffness gradients and forestall late complications such as AND.

Time-dependent effects of cellulose and gelatin-based hemostats on cellular processes of wound healing

INTRODUCTION

Oxidized regenerated cellulose-based (ORC - TABOTAMP), oxidized non-regenerated cellulose-based (ONRC - RESORBA CELL), and gelatin-based (GELA - GELITA TUFT-IT) hemostats are commonly used in surgery. However, their impact on the wound healing process remains largely unexplored. We here assess time-dependent effects of exposure to these hemostats on fibroblast-related wound healing processes.

MATERIAL AND METHODS

Hemostats were applied to fibroblast cell cultures for 5-10 (short-), 30 and 60 min (intermediate-) and 24 h (long-term). Representative images of the hemostat degradation process were obtained, and the pH value was measured. Cell viability, apoptosis and migration were analyzed after the above exposure times at 3, 6 and 24 h follow-up. Protein levels for tumor necrosis factor α (TNF-α) and transforming-growth factor β (TGF-β) were assessed.

RESULTS

ORC and ONRC reduced pH values during degradation, while GELA proved to be pH-neutral. Hemostat structural integrity was prolonged for GELA (vs. ORC and ONRC). TGF-β and TNF-α levels were reduced for ORC and ONRC (vs. GELA and control) (p < 0.05). Further, exposure of ORC and ONRC for longer than 5-10 min reduced cell viability vs. GELA and control at 3 h post-exposure (p < 0.05). Similarly, cell migration was impaired with ORC and ONRC exposure longer than 60 min at 24 h follow-up (p < 0.05).

CONCLUSIONS

Short-term exposure to ORC and ONRC impairs relevant wound healing-related processes in fibroblasts, and alters protein levels of key mediating cytokines. GELA does not show similar effects. We conclude that GELA may be preferred over ORC and ONRC over short-, intermediate- and long-term exposures. Future validation of the clinical relevance is warranted.

Nicotine Affects Murine Aortic Stiffness and Fatigue Response During Supraphysiological Cycling

Nicotine exposure is a major risk factor for several cardiovascular diseases. Although the deleterious effects of nicotine on aortic remodeling processes have been studied to some extent, the biophysical consequences are not fully elucidated. In this investigation, we applied quasi-static and dynamic loading to quantify ways in which exposure to nicotine affects the mechanical behavior of murine arterial tissue. Segments of thoracic aortas from C57BL/6 mice exposed to 25 mg/kg/day of subcutaneous nicotine for 28 days were subjected to uniaxial tensile loading in an open-circumferential configuration. Comparing aorta segments from nicotine-treated mice relative to an equal number of control counterparts, stiffness in the circumferential direction was nearly twofold higher (377 kPa ± 165 kPa versus 191 kPa ± 65 kPa, n = 5, p = 0.03) at 50% strain. Using a degradative power-law fit to fatigue data at supraphysiological loading, we observed that nicotine-treated aortas exhibited significantly higher peak stress, greater loss of tension, and wider oscillation band than control aortas (p ≤ 0.01 for all three variables). Compared to simple stress relaxation tests, fatigue cycling is shown to be more sensitive and versatile in discerning nicotine-induced changes in mechanical behavior over many cycles. Supraphysiological fatigue cycling thus may have broader potential to reveal subtle changes in vascular mechanics caused by other exogenous toxins or pathological conditions.

Translating mouse models of abdominal aortic aneurysm to the translational needs of vascular surgery

Introduction

Abdominal aortic aneurysm (AAA) is a condition that has considerable socioeconomic impact and an eventual rupture is associated with high mortality and morbidity. Despite decades of research, surgical repair remains the treatment of choice and no medical therapy is currently available. Animal models and, in particular, murine models, of AAA are a vital tool for experimental in vivo research. However, each of the different models has individual limitations and provide only partial mimicry of human disease. This narrative review addresses the translational potential of the available mouse models, highlighting unanswered questions from a clinical perspective. It is based on a thorough presentation of the available literature and more than a decade of personal experience, with most of the available models in experimental and translational AAA research.

Results

From all the models published, only the four inducible models, namely the angiotensin II model (AngII), the porcine pancreatic elastase perfusion model (PPE), the external periadventitial elastase application (ePPE), and the CaCl₂ model have been widely used by different independent research groups. Although the angiotensin II model provides features of dissection and aneurysm formation, the PPE model shows reliable features of human AAA, especially beyond day 7 after induction, but remains technically challenging. The translational value of ePPE as a model and the combination with β-aminopropionitrile to induce rupture and intraluminal thrombus formation is promising, but warrants further mechanistic insights. Finally, the external CaCl₂ application is known to produce inflammatory vascular wall thickening. Unmet translational research questions include the origin of AAA development, monitoring aneurysm growth, gender issues, and novel surgical therapies as well as novel nonsurgical therapies.

Conclusion

New imaging techniques, experimental therapeutic alternatives, and endovascular treatment options provide a plethora of research topics to strengthen the individual features of currently available mouse models, creating the possibility of shedding new light on translational research questions.

Outflow Through Aortic Side Branches Drives False Lumen Patency in Type B Aortic Dissection

Objective: Thoracic endovascular aortic repair (TEVAR) for type B aortic dissection (TBAD) aims to induce false lumen (FL) thrombosis by sealing intimal tears between the true (TL) and the FL, and blocking the inflow into the FL. Incomplete thrombosis of the FL is correlated with poor clinical outcome. We hypothesize that the number of major and minor branches arising from the FL affects FL patency and may negatively influence TEVAR induced FL thrombosis.

Methods: Computed tomography (CT)-scans from 89 patients diagnosed with TBAD [best medical treatment (BMT) n = 52, TEVAR n = 37] from two high-volume vascular surgery centers were analyzed retrospectively. Analysis included evaluation of the FL patency status, the number, location and size of intimal tears, and the presence of minor and major side branches originating from the FL. Multiple regression analysis was conducted to evaluate obtained parameters as predictors for FL thrombosis status.

Results: In univariate analysis, the strongest correlation for FL patency was found for the number of major (R = 0.79) and minor (R = 0.86) side branches originating from the FL. When applying a multiple linear regression model, the number of major (normalized beta 0.37; P < 0.001) and minor (normalized beta 0.41; P < 0.01) side branches arising from the FL were valid predictors for the axial length of the patent and non-patent FL, and additionally determined the length of the patent FL at 12-month follow-up in patients that underwent TEVAR.

Conclusions: Our data suggest that the number of minor side branches that originate from the FL in TBAD is an important determinant of FL patency, to a greater degree than previously assumed.

Exosome miR-501-3p Elevation Contributes to Progression of Vascular Stiffness

Background: Tight junction (TJ) disruption and dysfunction are involved in the progression of arteriosclerosis. miR-501-3p regulates endothelial TJ protein-1, resulting in TJ disruption. Because exosomal microRNAs can travel to distant tissues and influence cell behavior, patients with elevated miR-501-3p may experience accelerated vascular disease progression secondary to miR-501-3p-induced reductions in TJ. This study investigated whether plasma exosome miR-501-3p levels are associated with vascular stiffness, an indicator for arteriosclerotic changes. Methods and Results: Fifty-one subjects (mean [±SD] age 70±8 years, 37% male) enrolled in a medical checkup program were recruited to the study. Brachial-ankle arterial pulse wave velocity (baPWV) and plasma exosome miR-501-3p expression were measured. Patients were divided into 2 groups depending on whether their miR-501-3p ∆C_t values were above ("High"; n=24) or below ("Low"; n=27) the cut-off levels determined by receiver operating characteristic (ROC) curve analysis. Median (interquartile range) baPWV levels were significantly higher in the miR-501-3p High than Low group (1,664 [1,496-1,859] vs. 1,450 [1,353-1,686] cm/s, respectively; P<0.05). Multivariate logistic regression analysis showed a significant association between increased baPWV and High miR-501-3p expression (odds ratio 4.66). At follow-up visits (mean 62 months later), baPWV remained significantly higher in the miR-501-3p High than Low group (1,830 [1,624-2,056] vs. 1,620 [1,377-1,816] cm/s, respectively; P<0.05). Conclusions: High expression levels of exosome miR-501-3p contribute to arteriosclerotic changes.

Systemic Upregulation of IL-10 (Interleukin-10) Using a Nonimmunogenic Vector Reduces Growth and Rate of Dissecting Abdominal Aortic Aneurysm

Objective- Recruitment of immunologic competent cells to the vessel wall is a crucial step in formation of abdominal aortic aneurysms (AAA). Innate immunity effectors (eg, macrophages), as well as mediators of adaptive immunity (eg, T cells), orchestrate a local vascular inflammatory response. IL-10 (interleukin-10) is an immune-regulatory cytokine with a crucial role in suppression of inflammatory processes. We hypothesized that an increase in systemic IL-10-levels would mitigate AAA progression. Approach and Results- Using a single intravenous injection protocol, we transfected an IL-10 transcribing nonimmunogenic minicircle vector into the Ang II (angiotensin II)-ApoE^-/- infusion mouse model of AAA. IL-10 minicircle transfection significantly reduced average aortic diameter measured via ultrasound at day 28 from 166.1±10.8% (control) to 131.0±5.8% (IL-10 transfected). Rates of dissecting AAA were reduced by IL-10 treatment, with an increase in freedom from dissecting AAA from 21.5% to 62.3%. Using flow cytometry of aortic tissue from minicircle IL-10-treated animals, we found a significantly higher percentage of CD4⁺/CD25⁺/Foxp3 (forkhead box P3)⁺ regulatory T cells, with fewer CD8⁺/GZMB⁺ (granzyme B) cytotoxic T cells. Furthermore, isolated aortic macrophages produced less TNF-α (tumor necrosis factor-α), more IL-10, and were more likely to be MRC1 (mannose receptor, C type 1)-positive alternatively activated macrophages. These results concurred with gene expression analysis of lipopolysaccharide-stimulated and Ang II-primed human peripheral blood mononuclear cells. Conclusions- Taken together, we provide an effective gene therapy approach to AAA in mice by enhancing antiinflammatory and dampening proinflammatory pathways through minicircle-induced augmentation of systemic IL-10 expression.

An Automated Algorithm to Quantify Collagen Distribution in Aortic Wall

Arterial diseases including abdominal aortic aneurysm and atherosclerosis are biomechanical diseases characterized by significant changes in the structure and strength of the vessel wall. It is now established that local variations in fibrillar collagen and elastin matrix turnover is critical to arterial stiffening and progression of the disease. The collagen content in the aortic wall has nominally been quantified by biochemical assays and immunohistochemical analysis as the total amount because of the difficulty in separating the media and adventitia. In this work, we have developed an algorithm for automatic quantification of layer-specific collagen content from bright-field and polarized microscopic images of histological sections of mouse aorta stained with Picrosirius red (PSR) stain. The images were processed sequentially including separation of layers, erosion, segregation of regions, binarization, and quantification of pixel intensities to obtain collagen content in the media and adventitia separately. We observed that the automated algorithm rapidly and accurately quantified collagen content from a wide range of image quality compared with manual measurements particularly when the medial and adventitial layers overlap. Together, our algorithm will be of significant impact in the rapid, reliable, and accurate analyses of collagen distribution in histological sections of connective tissues.

Chronic Nicotine Exposure Induces Murine Aortic Remodeling and Stiffness Segmentation-Implications for Abdominal Aortic Aneurysm Susceptibility

Aim: Arterial stiffness is a significant risk factor for many cardiovascular diseases, including abdominal aortic aneurysms (AAA). Nicotine, the major active ingredient of e-cigarettes and tobacco smoke, induces acute vasomotor effects that may temporarily increase arterial stiffness. Here, we investigated the effects of long-term nicotine exposure on structural aortic stiffness. Methods: Mice (C57BL/6) were infused with nicotine for 40 days (20 mg/kg/day). Arterial stiffness of the thoracic (TS) and abdominal (AS) aortic segments was analyzed using ultrasound (PWV, pulse wave velocity) and ex vivo pressure myograph measurements. For mechanistic studies, aortic matrix-metalloproteinase (MMP) expression and activity as well as medial elastin architecture were analyzed. Results: Global aortic stiffness increased with nicotine. In particular, local stiffening of the abdominal segment occurred after 10 days, while thoracic aortic stiffness was only increased after 40 days, resulting in aortic stiffness segmentation. Mechanistically, nicotine exposure enhanced expression of MMP-2/-9 and elastolytic activity in both aortic segments. Elastin degradation occurred in both segments; however, basal elastin levels were higher in the thoracic aorta. Finally, MMP-inhibition significantly reduced nicotine-induced MMP activity, elastin destruction, and aortic stiffening. Conclusion: Chronic nicotine exposure induces aortic MMP expression and structural aortic damage (elastin fragmentation), irreversibly increasing aortic stiffness. This process predominantly affects the abdominal aortic segment, presumably due in part to a lower basal elastin content. This novel phenomenon may help to explain the role of nicotine as a major risk factor for AAA formation and has health implications for ECIGs and other modes of nicotine delivery.

Open surgery for iliofemoral deep vein thrombosis with temporary arteriovenous fistula remains valuable

Objective We assessed outcomes of open surgical venous thrombectomy with temporary arteriovenous fistula, and the procedure's effect on health-related quality of life. Method We retrospectively analyzed 48 (26 at long-term) patient medical records. Mortality rates, patency, and risk of post-thrombotic syndrome were analyzed using Kaplan-Meier estimation. The association between risk factors/coagulation disorders and patency/post-thrombotic syndrome along with patient health-related quality of life at long-term was analyzed employing various statistical methods. Results Patient one-year survival rate was 93 ± 4% and primary one-year patency rate was 89 ± 5% (secondary one-year patency rate 97 ± 3%). Freedom from post-thrombotic syndrome after eight years was 80 ± 12% (post-thrombotic syndrome rate 20 ± 12%). Health-related quality of life was impaired vs. normative data in the physical and social subscales, and in the mental component score ( p < .05). Conclusions Open surgical venous thrombectomy appears safe compared with literature-reported outcomes in similar patients using alternative approaches. Iliofemoral deep vein thrombosis impairs physical, social, and mental health-related quality of life.

Chronic Mesenteric Ischemia: Patient Outcomes Using Open Surgical Revascularization

BACKGROUND

Chronic mesenteric ischemia (CMI) is a rare disease. Open treatment (OT) remains a valuable treatment option. We analyzed patient outcomes after OT and investigated health-related quality of life (HRQoL).

METHODS

Data were analyzed retrospectively. The investigation period was from January 1, 2001, to December 31, 2014. We investigated mortality and patency rates using Kaplan-Meier analysis. HRQoL was measured using a 36-item health survey. Various statistical methods were employed.

RESULTS

A total of 100 patients (celiac trunk [TC: n = 23], superior mesenteric artery [SMA: n = 26], or both [n = 51]) were included. Median follow-up was 5 ± 35 months. One-year survival rate for TC was 75 ± 11%, for SMA: 79 ± 10%, and for both: 96 ± 3%. TC 5-year survival was 75 ± 11% (SMA: 57 ± 16%: both: 80 ± 8%). Obesity and the length of hospital stay were independently associated with patient survival (p < 0.05). Primary 1-year patency rate was 60 ± 13% for TC (SMA: 86 ± 10%; both: 71 ± 8%) and secondary 1-year patency rate was 84 ± 9% for TC (SMA: 100%; both: 79 ± 7%). HRQoL was inferior compared to the German normative data (p < 0.05).

CONCLUSION

CMI overlaps between gastrointestinal and vascular surgery. OT is safe, and simultaneous revascularization of the TC and the SMA does not affect mortality. Patients would not necessarily benefit from OT in terms of HRQoL.

Assessment of essential characteristics of two different scaffolds for tendon in situ regeneration

PURPOSE

Rotator cuff tears are challenging as the rate of re-ruptures remains high. Thus, new therapeutic strategies need to be developed. Tendon in situ regeneration (TSR) attempts to produce cell-scaffold constructs in vitro, which can produce tendinous tissue of high quality after replantation. Therefore, it is essential to find suitable scaffolds that can provide acceptable biofunctionality and biocompatibility. This study compares characteristics of scaffolds for in situ regeneration: a polyglycolic acid/PDS scaffold (PP-sca) (Ethisorb, Ethicon, Germany) and a collagen sponge (col-spo) (TissueTek, Germany) with a basal strengthening membrane.

METHODS

Tendon-derived cells (TDCs) were isolated from the long head of the biceps tendon. Gene expression for collagen type I, collagen type III, decorin, scleraxis and tenomodulin was analysed in the third cell passage. Cell proliferation in cell seeded scaffolds was tested using a WST-1 assay. In addition, the tensile strength of both scaffolds was measured using a universal-testing machine (Zwick/Roell, Ulm, Germany).

RESULTS

The results from this study indicate a genotypic drift during the in vitro cultivation of the TDCs. The PP-sca showed good biofunctional results, including low initial loss of cells after cell seeding. The proliferation rates were approximately equal in each type of scaffold. The col-spo provided superior tensile strength compared with the PP-sca (p < 0.01).

CONCLUSION

Overall, the col-spo seems to be more suitable for TSR. It may become a clinical alternative in the future to achieve more satisfying results, concerning function and pain.

LEVEL OF EVIDENCE

Experimental study/case series, Level IV.

Long-term results of open repair of popliteal artery aneurysm

INTRODUCTION

Popliteal artery aneurysms (PAA) are rare. Different surgical techniques for open surgical repair are possible. This study presents a single centre experience using open surgical repair with a medial approach (MA) and outlines differences between symptomatic (SLS) and asymptomatic (ALS) legs.

METHODS

Data collection was performed retrospectively. The investigation period was from 1 January 1996 to 1 January 2013. Patients presented in the Outpatient Department and received a questionnaire concerning their quality of life. Data are presented as mean ± standard deviation. Mann-Whitney test and Cochran-Armitage test for trend was used for data analysis. Kaplan-Meier method was used to calculate limb salvage rates. p < 0.05 was considered statistically significant.

RESULTS

We analyzed 16 ALS and 26 SLS with an average age of 63.5 ± 10 years. Preoperative ankle-brachial index (ABI) was 1.0 ± 0.2 for ALS (on control examination: 1.12 ± 0.24) and 0.08 ± 0.18 for SLS (on control examination 0.94 ± 0.14) (p < 0.05). Limb salvage rate was 100% for ALS and 86.7% for SLS (overall 93.3%). Primary patency rate for SLS was 85%, for ALS rate of 100%, respectively (overall 92.5%). ALS reached an average of 13.1 ± 2.7 points (SLS 11.4 ± 2.8) on a numeric point scale.

CONCLUSION

Open surgery is therapy and prevention of acute ischaemia all in one, especially for asymptomatic patients and delivers good long-term results. Endovascular therapies offer an alternative but long-term results are pending. Open surgery should still be considered as a gold standard therapy.

Spontaneous rupture of an isolated iliac artery dissection in a young man because of cystic medial degeneration Erdheim-Gsell

BACKGROUND

Rupture of isolated iliac artery dissections is a life-threatening event and has not been associated with cystic medial degeneration (CMD) Erdheim-Gsell.

METHODS

A young man presented to our emergency unit in a critical hemodynamic condition. Computed tomography scan feigned the rupture of an internal iliac artery.

RESULTS

Surprisingly, we found a ruptured dissection of the common iliac artery during open surgery. Reconstruction was done by Dacron graft interposition between common and internal iliac artery and external iliac artery implantation into the graft. Histology revealed CMD.

CONCLUSIONS

Spontaneous iliac artery dissection and rupture can be caused by CMD and requires immediate surgical intervention.

The long head of the biceps tendon is a suitable cell source for tendon tissue regeneration

INTRODUCTION

Tendon tissue engineering (TTE) tries to produce tendinous tissue of high quality to replace dysfunctional tissue. One possible application of TTE might be the replacement of ruptured tissue of the rotator cuff. Autologous tenocytes seem to be most suitable as no differentiation in vitro is necessary. Today it is still uncertain if there is a difference between tendon-derived cells (TDC) of different native tissues. Moreover, the search for suitable scaffolds is another important issue in TTE.

MATERIAL AND METHODS

This study compared TDC of the long head of the biceps tendon (LHB), the anterior cruciate ligament (ACL) and the tendon of the musculus semitendinosus (TMS). The TDC were isolated using the cell migration method. Cell morphology was assessed using light microscopy and gene expression was performed using polymerase chain reaction (PCR). Afterwards, cell seeding efficiency and proliferation were tested on a collagen I scaffold using the WST-1 assay. Results were confirmed using H + E staining.

RESULTS

The TDC of the LHB showed higher expression levels of collagen type I and decorin (p < 0.01) compared to TDC of other origin. Results showed efficient cell seeding and proliferation within the scaffold. Proliferation within the scaffold was not as high as when cells were cultivated without a scaffold.

CONCLUSIONS

The TDC of the LHB seems to be the most suitable cell source. Further research is necessary to find out if the results can be transferred to an in vivo model. The new collagen I scaffold seems to offer an opportunity to combine good biocompatibility and mechanical strength.

A 61-year-old man with disseminated intravascular coagulation: a case report

BACKGROUND

Disseminated intravascular coagulation (DIC) can frequently be observed in patients with severe inflammatory response. It is still correlated with a poor prognosis. Activation of coagulation activity leads to occlusions of small vessels resulting in various organ failure symptoms. In addition, secondary fibrinolysis leads to an increased risk of bleedings and means a therapeutic dilemma. Here, we present a case of a 61-year-old Caucasian man with a severe case of DIC and its clinical complications.

METHODS

We report the case of a man with a severe case of DIC. Data collection was performed retrospectively.

RESULTS

We report the case of a 61-year-old Caucasian man with contact to pigeon droppings in his medical history. This was followed by a rhinopharyngitis, an exanthema, and a recurring priapism. Thrombotic occlusions were predominant on admission, and necrosis of the lower legs, the hands, and the genital resulted in amputation. Hypoperfusion of the rectum and the bladder lead to the creation of a descendostoma and an uretrostoma. Anticoagulation was managed by continuous infusion of unfractionated heparin and activated protein C supplementation. Long-term anticoagulation is managed with rivaroxaban.

CONCLUSIONS

Cryptococcus soil inhalation may cause severe DIC resulting in extremity amputations; however, effective anticoagulation and activated protein C supplementation might extenuate the progress. As multiple complications might occur, an interdisciplinary cooperation is essential.

Collagen type I and decorin expression in tenocytes depend on the cell isolation method

Backround

The treatment of rotator cuff tears is still challenging. Tendon tissue engineering (TTE) might be an alternative in future. Tenocytes seem to be the most suitable cell type as they are easy to obtain and no differentiation in vitro is necessary. The aim of this study was to examine, if the long head of the biceps tendon (LHB) can deliver viable tenocytes for TTE. In this context, different isolation methods, such as enzymatic digestion (ED) and cell migration (CM), are investigated on differences in gene expression and cell morphology.

Methods

Samples of the LHB were obtained from patients, who underwent surgery for primary shoulder arthroplasty. Using ED as isolation method, 0.2% collagenase I solution was used. Using CM as isolation method, small pieces of minced tendon were put into petri-dishes. After cell cultivation, RT-PCR was performed for collagen type I, collagen type III, decorin, tenascin-C, fibronectin, Scleraxis, tenomodulin, osteopontin and agreccan.

Results

The total number of isolated cells, in relation to 1 g of native tissue, was 14 times higher using ED. The time interval for cell isolation was about 17 hours using ED and approximately 50 days using CM. Cell morphology in vitro was similar for both isolation techniques. Higher expression of collagen type I could be observed in tenocyte-like cell cultures (TLCC) using ED as isolation method (p < 0.05), however decorin expression was higher in TLCC using CM as isolation method (p < 0.05). Dedifferentiation potential seemed to be similar for both isolation techniques.

Conclusion

In summary tenocyte-like cells can be obtained with both isolation methods (ED and CM) from the LHB. As no obvious disadvantage could be seen using ED, this method is more suitable for clinical use, as time for cell isolation is shorter and a remarkably higher number of cells can be obtained. However, both isolation methods can further be improved.