Increased Aortic Exclusion in Endovascular Treatment of Complex Aortic Aneurysms

PURPOSE

Perioperative risk assessments for complex aneurysms are based on the anatomical extent of the aneurysm and do not take the length of the aortic exclusion into account, as it was developed for open repair. Nevertheless, in the endovascular repair (ER) of complex aortic aneurysms, additional segments of healthy aorta are excluded compared with open repair (OR). The aim of this study was to assess differences in aortic exclusion between the ER and OR of complex aortic aneurysms, to subsequently assess the current classification for complex aneurysm repair.

METHODS

This retrospective observational study included patients that underwent complex endovascular aortic aneurysm repair by means of fenestrated endovascular aneurysm repair (FEVAR), fenestrated and branched EVAR (FBEVAR), or branched EVAR (BEVAR). The length of aortic exclusion and the number of patent segmental arteries were determined and compared per case in ER and hypothetical OR, using a Wilcoxon signed-rank test.

RESULTS

A total of 71 patients were included, who were treated with FEVAR (n = 44), FBEVAR (n = 8), or BEVAR (n = 19) for Crawford types I (n = 5), II (n = 7), III (n = 6), IV (n = 7), and V (n = 2) thoracoabdominal or juxtarenal (n = 44) aneurysms. There was a significant increase in the median exclusion of types I, II, III, IV, and juxtarenal aneurysms (p < 0.05) in ER, compared with hypothetical OR. The number of patent segmental arteries in the ER of type I-IV and juxtarenal aneurysms was significantly lower than in hypothetical OR (p < 0.05).

CONCLUSION

There are significant differences in the length of aortic exclusion between ER and hypothetical OR, with the increased exclusion in ER resulting in a lower number of patent segmental arteries. The ER and OR of complex aortic aneurysms should be regarded as distinct modalities, and as each approach deserves a particular risk assessment, future efforts should focus on reporting on the extent of exclusion per treatment modality, to allow for appropriate comparison.

Partial Right Atrial Inflow Occlusion for Transient Systemic Hypotension During Deployment of Thoracic Stentgrafts

Purpose

Temporary balloon occlusion of the inferior vena cava to lower cardiac output is a relatively infrequently used technique to induce controlled systemic hypotension. In this technical note, we describe the feasibility, reliability, and safety of partial occlusion of right atrial inflow and the effect on systemic blood pressure during the deployment of a thoracic stentgraft.

Materials and Methods

Twenty consecutive patients undergoing thoracic endovascular aortic repair, with proximal landing in zone 0–3 of the thoracic aorta, were prospectively included. Right atrial inflow occlusion was performed with a compliant occlusion balloon.

Results

Median time to reach a mean arterial pressure of 50 mmHg was 43 s. Median recovery time of blood pressure was 42 s.

Conclusion

Partial right atrial inflow occlusion with an occlusion balloon is feasible with reliable results and without procedure-related complications.

A 'Final Destination injury': Penetrating trauma of the neck and a pneumomediastinum by a metal part shot from a lawnmower

Introduction

Outside of war regions, penetrating neck injury is rare. Penetrating neck injury due to a lawnmower has never been described, despite the annual 74.000 injuries caused by lawnmowers in the United States. In this report, the case of a 65-year old women, admitted after a penetrating neck injury due to a metal piece shot from a lawnmower, is described.

Report

A 65-year old women, with no relevant medical history, presented at the Emergency Department after she was hit in the neck by an iron projectile shot from a professional lawnmower. On site, the projectile, a metal part from the lawnmower blade, was removed by her husband. CT scan showed a pneumomediastinum, without signs of vascular injury. Surgical exploration was immediately performed in the operation room (OR). No vascular or esophageal injuries werefound, only lacerated neck muscles. Perioperatively, the ENT surgeon performed an endoscopy, which showed a small injury of the hypopharynx. Postoperatively, the patient was prophylactically treated with antibiotics for 7 days. Patient was discharged in good clinical condition after 7 days, without complications.

Conclusion

In this report we present a case with a sharp traumatic injury of the neck, caused by a metal projectile shot from a lawnmower. The laceration of the pharynx was explored in the OR by the ENT- and vascular surgeon. The pneumomediastinum was treated with prophylactic antibiotics. Currently the patient is doing fine without any complications of the injury. Traumatic injury of the neck requires direct direct surgical exploration, however, when patients present hemodynamically stable, a neck CTA will add to the diagnosis (e.g. a pneumomediastium).

Editor's Choice - Nationwide Analysis of Patients Undergoing Iliac Artery Aneurysm Repair in the Netherlands

OBJECTIVE

The new 2019 guideline of the European Society for Vascular Surgery (ESVS) recommends consideration for elective iliac artery aneurysm (eIAA) repair when the iliac diameter exceeds 3.5 cm, as opposed to 3.0 cm previously. The current study assessed diameters at time of eIAA repair and ruptured IAA (rIAA) repair and compared clinical outcomes after open surgical repair (OSR) and endovascular aneurysm repair (EVAR).

METHODS

This retrospective observational study used the nationwide Dutch Surgical Aneurysm Audit (DSAA) registry that includes all patients who undergo aorto-iliac aneurysm repair in the Netherlands. All patients who underwent primary IAA repair between 1 January 2014 and 1 January 2018 were included. Diameters at time of eIAA and rIAA repair were compared in a descriptive fashion. The anatomical location of the IAA was not registered in the registry. Patient characteristics and outcomes of OSR and EVAR were compared with appropriate statistical tests.

RESULTS

The DSAA registry comprised 974 patients who underwent IAA repair. A total of 851 patients were included after exclusion of patients undergoing revision surgery and patients with missing essential variables. eIAA repair was carried out in 713 patients, rIAA repair in 102, and symptomatic IAA repair in 36. OSR was performed in 205, EVAR in 618, and hybrid repairs and conversions in 28. The median maximum IAA diameter at the time of eIAA and rIAA repair was 43 (IQR 38-50) mm and 68 (IQR 58-85) mm, respectively. Mortality was 1.3% (95% CI 0.7-2.4) after eIAA repair and 25.5% (95% CI 18.0-34.7) after rIAA repair. Mortality was not significantly different between the OSR and EVAR subgroups. Elective OSR was associated with significantly more complications than EVAR (intra-operative: 9.8% vs. 3.6%, post-operative: 34.0% vs. 13.8%, respectively).

CONCLUSION

In the Netherlands, most eIAA repairs are performed at diameters larger than recommended by the ESVS guideline. These findings appear to support the recent increase in the threshold diameter for eIAA repair.

Vascular access training for REBOA placement: a feasibility study in a live tissue-simulator hybrid porcine model

Background

The use of resuscitative endovascular balloon occlusion of the aorta (REBOA) in patients with severe haemorrhagic shock is increasing. Obtaining vascular access is a necessary prerequisite for REBOA placement in these situations.

Methods

During the EVTM workshop (September 2017, Örebro, Sweden), 21 individuals participated in this study, 16 participants and five instructors. A formalised curriculum was constructed including basic anatomy of the femoral region and basic training in access materials for REBOA placement in zone 1. Key skills: (1) preparation of endovascular toolkit, (2) achieving vascular access in the model and (3) bleeding control with REBOA. Scoring ranged from 0 to 5 for non-anatomical skills. Identification of anatomical structures was either sufficient (score=1) or insufficient (score=0). Five consultants performed a second identical procedure as a post test.

Results

Consultants had significantly better overall technical skills in comparison with residents (p=0.005), while understanding of surgical anatomy showed no difference. Procedure times differed significantly (p<0.01), with residents having a median procedure time of 3 min and 24 s, consultants 2:33 and instructors 1:09.

Conclusion

This comprehensive training model using a live tissue-simulator hybrid porcine model can be used for femoral access and REBOA placement training in medical personnel with different prior training levels. Higher levels of training are associated with faster procedure times. Further research in open and percutaneous access training is necessary to simulate real-life situations. This training method can be used in a multistep training programme, in combination with realistic moulage and perfused cadaver models.

Outcomes after foot surgery in people with a diabetic foot ulcer and a 12-month follow-up

OBJECTIVE

The aim of this study was to retrospectively measure the outcomes of foot-sparing surgery at one year follow-up for patients with diabetic foot ulcers (DFUs). We assessed wound healing and the need for further surgery in relation to the variables that influence healing.

METHOD

Data were retrospectively collected by reviewing the electronic files of patients attending the Wound Expert Clinic (WEC). Outcomes of surgical debridement, toe, ray and transmetatarsal amputations were assessed.

RESULTS

A total of 129 cases in 121 patients were identified for inclusion. The results demonstrated that complete wound healing was reached in 52% (61/117) of the patients within 12 months. The need for additional surgery or for major amputation was 56% (n=72/129) and 30% (n=39/129) respectively. The need for an additional procedure was particularly high after surgical debridement (75%, 33/44) and transmetatarsal amputation (64%, 7/11). Risk factors for non-healing or for a major amputation were: infection (p=0.01), ischaemia (p=0.01), a history of peripheral arterial occlusive disease (p<0.01) and smoking (p=0.01). Additional findings were that not all patients underwent vascular assessment and in half of the patients there was a delay in undergoing revascularisation.

CONCLUSION

The results of the study reveal some areas for improvement including timely revascularisation and performance of multiple debridement procedures if needed in order to save a limb.

Aortic Aneurysm Rupture After Urokinase Treatment for Acute Limb Ischemia in Two Patients After EVAR

Endovascular aneurysm repair (EVAR) is first-choice treatment for many patients with abdominal aortic aneurysms. Complications unique to endovascular treatment include endoleak and endotension, which can eventually lead to rupture. We present two cases of late aortic rupture after EVAR, where both patients had recent preceding catheter-directed thrombolysis with urokinase for acute limb ischemia. These cases suggest a relation between thrombolytic therapy and aortic rupture after EVAR, and we should therefore be aware of this possible complication.

Ruptured AAA: state of the art management

Since its introduction more than two decades ago, endovascular aneurysm repair (EVAR) has become the primary choice for elective treatment of abdominal aortic aneurysms (AAA) in many medical centers. The (dis)advantages, including 30-day mortality and long-term survival, of both open and endovascular elective AAA repair have been studied extensively, including four randomized trials. On the contrary, the survival benefit of EVAR for ruptured AAAs is not as well established as in elective situations. In the absence of randomized trials, the best treatment modality for ruptured AAA has not been revealed. In this manuscript, we describe the design and (preliminary) results of recently completed and ongoing randomized trials. Furthermore, the trends in management and the results of the treatment of ruptured AAA in our tertiary center over a 20-year period are presented. In the last decade, a progressive increase in the proportion of patients managed by EVAR was observed. This increase was associated with an overall increase in the number of treated patients and, simultaneously, a decrease in the overall 30-day mortality (53% versus 39%) was seen when comparing the two last decades. The 30-day mortality rates were significantly lower in the patients treated with EVAR (24%) compared to open repair (52%). The survival advantage for EVAR after ruptured AAA persisted during the first 5 years after repair, but was lost after that period. The estimated 5-year survival was 44% and 39% for EVAR and open repair, respectively. These data support that endovascular repair is an effective and safe strategy as a primary treatment modality for ruptured AAA.

A novel urokinase receptor-targeted inhibitor for plasmin and matrix metalloproteinases suppresses vein graft disease

AIMS

Matrix metalloproteinases (MMP) and plasminogen activator (PA)/plasmin-mediated proteolysis, especially at the cell surface, play important roles in matrix degeneration and smooth muscle cell migration, which largely contributes to vein graft failure. In this study, a novel hybrid protein was designed to inhibit both protease systems simultaneously. MMP and plasmin activity were inhibited at the cell surface by this hybrid protein, consisting of the receptor-binding amino-terminal fragment (ATF) of urokinase-type PA, linked to both the tissue inhibitor of metalloproteinases (TIMP-1) and bovine pancreas trypsin inhibitor (BPTI), a potent protease inhibitor. The effect of overexpression of this protein on vein graft disease was studied.

METHODS AND RESULTS

A non-viral expression vector encoding the hybrid protein TIMP-1.ATF.BPTI was constructed and validated. Next, cultured segments of human veins were transfected with this vector. Expressing TIMP-1.ATF.BPTI in vein segments resulted in a mean 36 ± 14% reduction in neointima formation after 4 weeks. In vivo inhibition of vein graft disease by TIMP-1.ATF.BPTI is demonstrated in venous interpositions placed into carotid arteries of hypercholesterolaemic APOE*3Leiden mice. After 4 weeks, vein graft thickening was significantly inhibited in mice treated with the domains TIMP-1, ATF, or BPTI (36-49% reduction). In the TIMP-1.ATF.BPTI-treated mice, vein graft thickening was reduced by 67±4%, which was also significantly stronger when compared with the individual components.

CONCLUSION

These data provide evidence that cell surface-bound inhibition of the PA and MMP system by the hybrid protein TIMP-1.ATF.BPTI, overexpressed in distant tissues after electroporation-mediated non-viral gene transfer, is a powerful approach to prevent vein graft disease.

Natural Killer Cells and CD4 + T-Cells Modulate Collateral Artery Development

Objective— The immune system is thought to play a crucial role in regulating collateral circulation (arteriogenesis), a vital compensatory mechanism in patients with arterial obstructive disease. Here, we studied the role of lymphocytes in a murine model of hindlimb ischemia.

Methods and Results— Lymphocytes, detected with markers for NK1.1, CD3, and CD4, invaded the collateral vessel wall. Arteriogenesis was impaired in C57BL/6 mice depleted for Natural Killer (NK)-cells by anti-NK1.1 antibodies and in NK-cell–deficient transgenic mice. Arteriogenesis was, however, unaffected in Jα281-knockout mice that lack NK1.1 + Natural Killer T (NKT)-cells, indicating that NK-cells, rather than NKT-cells, are involved in arteriogenesis. Furthermore, arteriogenesis was impaired in C57BL/6 mice depleted for CD4 + T-lymphocytes by anti-CD4 antibodies, and in major histocompatibility complex (MHC)-class-II–deficient mice that more selectively lack mature peripheral CD4 + T-lymphocytes. This impairment was even more profound in anti-NK1.1-treated MHC-class-II–deficient mice that lack both NK- and CD4 + T-lymphocytes. Finally, collateral growth was severely reduced in BALB/c as compared with C57BL/6 mice, 2 strains with different bias in immune responsiveness.

Conclusions— These data show that both NK-cells and CD4 + T-cells modulate arteriogenesis. Promoting lymphocyte activation may represent a promising method to treat ischemic disease.

Sirolimus and paclitaxel provoke different vascular pathological responses after local delivery in a murine model for restenosis on underlying atherosclerotic arteries

BACKGROUND

Drug-eluting stents (DES) have been introduced successfully in clinical practice to prevent post-angioplasty restenosis. Nevertheless, concerns about the safety of DES still exist.

OBJECTIVE

To investigate the vascular pathology and transcriptional responses to sirolimus and paclitaxel in a murine model for restenosis on underlying diseased atherosclerotic arteries.

METHODS

Atherosclerotic lesions were induced by placement of a perivascular cuff around the femoral artery of hypercholesterolaemic ApoE*3-Leiden transgenic mice. Two weeks later these cuffs were replaced either by sirolimus- or paclitaxel-eluting cuffs. The vascular pathological effects were evaluated after two additional weeks.

RESULTS

Both anti-restenotic compounds significantly inhibited restenotic lesion progression on the atherosclerotic plaques. Vascular histopathological analyses showed that local delivery of sirolimus has no significant adverse effects on vascular disease. Conversely, high dosages of paclitaxel significantly increased apoptosis, internal elastic lamina disruption, and decreased medial and intimal smooth muscle cells and collagen content. Moreover, transcriptional analysis by real-time RT-PCR showed an increased level of pro-apoptotic mRNA transcripts (FAS, BAX, caspase 3) in paclitaxel-treated arteries.

CONCLUSIONS

Sirolimus and paclitaxel are effective in preventing restenosis. Sirolimus has no significant effect on arterial disease. In contrast, paclitaxel at high concentration demonstrated adverse vascular pathology and transcriptional responses, suggesting a narrower therapeutic range of this potent drug. Since the use of overlapping stents is becoming more common in DES technology, this factor is important, given that higher dosages of paclitaxel may lead to increased apoptosis in the vessel wall and, consequently, to a more unstable phenotype of the pre-existing atherosclerotic lesion.

Interleukin 10: a new risk marker for the development of restenosis after percutaneous coronary intervention

Genetic factors appear to be important in the process of restenosis after percutaneous coronary intervention (PCI), as well as in inflammation, a pivotal factor in restenosis. An important mediator in the inflammatory response is interleukin (IL)-10. Our aim was to study whether genetic variants in IL-10 predispose to the risk of restenosis. The GENetic DEterminants of Restenosis (GENDER) study included 3104 patients treated with successful PCI. Target vessel revascularization (TVR) was chosen as primary end point. Genotyping of the -2849G/A, -1082G/A, -592C/A and +4259A/G polymorphisms of the IL-10 gene was performed by MassArray platform. After adjusting for clinical variables, three polymorphisms significantly increased the risk of restenosis (-2849AA: relative risk (RR), 1.7, 95% confidence interval (CI), 1.2-2.5; -1082AA: RR, 1.4, 95% CI, 1.1-1.8 and +4259GG: RR, 2.0, 95% CI, 1.4-2.8). To further exclude possible involvement of neighboring genes due to LD in the IL-10 locus, additional polymorphisms were genotyped. The results reveal that association of the IL-10 gene with restenosis is independent of flanking genes. Our findings demonstrate that IL-10 is associated with restenosis and therefore support the hypothesis that anti-inflammatory genes also may be involved in developing restenosis. Furthermore, they may provide a new targeting gene for drug-eluting stents.

The effect of interleukin-10 knock-out and overexpression on neointima formation in hypercholesterolemic APOE*3-Leiden mice

OBJECTIVE

Inflammatory factors are thought to play a regulatory role in restenosis. Interleukin-10 (IL10) is an important anti-inflammatory cytokine with anti-atherogenic potentials. The aim of this study was to assess the effects of IL10 modulation on cuff-induced neointima formation in hypercholesterolemic APOE*3-Leiden mice.

METHODS

The involvement of IL10 in neointima formation was studied in a hypercholesterolemic mouse model of cuff-induced stenosis of the femoral artery by IL10 knocking-out or overexpression procedures. IL10(+/-) mice were crossbred with APOE*3-Leiden mice to generate hypercholesterolemic APOE*3-LeidenIL10(-/-) mice. To achieve IL10 overexpression in APOE*3-Leiden mice, a single intramuscular injection of a murine IL10 overexpression plasmid was performed followed by electroporation.

RESULTS

Knocking-out IL10, in hypercholesterolemic APOE*3-Leiden mice, resulted in a significant 1.9-fold increase of neointima surface as compared to APOE*3-LeidenIL10(+/+) littermates (p=0.02). Conversely, a marked 45% inhibition on cuff-induced neointima formation was obtained after IL10 overexpression (p=0.02). Electrodelivery of IL10 vector leads to detectable IL10 serum levels, with a sustained expression over the experimental period of 3 weeks. IL10 overexpression reduced plasma cholesterol levels in APOE*3-Leiden mice, whereas IL10 deficiency in these mice did not lead to altered cholesterol levels as compared to the IL10(+/+) group. Finally, IL10 overexpression stimulated endogenous IL10 mRNA expression in the spleen and reduced the transcriptional responses of several pro-inflammatory cytokines.

CONCLUSION

Here, we clearly demonstrate the role of IL10 in the development of neointima formation in hypercholesterolemic mice and the potential therapeutic effect of non-viral electrodelivery of IL10 cDNA to inhibit post-angioplasty restenosis.

Murine models of myocardial and limb ischemia: Diagnostic end-points and relevance to clinical problems

Ischemic disease represents the new epidemic worldwide. Animal models of ischemic disease are useful because they can help us to understand the underlying pathogenetic mechanisms and develop new therapies. The present review article summarizes the results of a consensus conference on the status and future development of experimentation in the field of cardiovascular medicine using murine models of peripheral and myocardial ischemia. The starting point was to recognize the limits of the approach, which mainly derive from species- and disease-related differences in cardiovascular physiology. For instance, the mouse heart beats at a rate 10 times faster than the human heart. Furthermore, healing processes are more rapid in animals, as they rely on mechanisms that may have lost relevance in man. The main objective of the authors was to propose general guidelines, diagnostic end points and relevance to clinical problems.

Anti-MCP-1 gene therapy inhibits vascular smooth muscle cells proliferation and attenuates vein graft thickening both in vitro and in vivo

OBJECTIVE

Because late vein graft failure is caused by intimal hyperplasia (IH) and accelerated atherosclerosis, and these processes are thought to be inflammation driven, influx of monocytes is one of the first phenomena seen in IH, we would like to provide direct evidence for a role of the MCP-1 pathway in the development of vein graft disease.

METHODS AND RESULTS

MCP-1 expression is demonstrated in various stages of vein graft disease in a murine model in which venous interpositions are placed in the carotid arteries of hypercholesterolemic ApoE3Leiden mice and in cultured human saphenous vein (HSV) segments in which IH occurs. The functional involvement of MCP-1 in vein graft remodeling is demonstrated by blocking the MCP-1 receptor CCR-2 using 7ND-MCP-1. 7ND-MCP1 gene transfer resulted in 51% reduction in IH in the mouse model, when compared with controls. In HSV cultures neointima formation was inhibited by 53%. In addition, we demonstrate a direct inhibitory effect of 7ND-MCP-1 on the proliferation of smooth muscle cell (SMC) in HSV cultures and in SMC cell cultures.

CONCLUSIONS

These data, for the first time, prove that MCP-1 has a pivotal role in vein graft thickening due to intimal hyperplasia and accelerated atherosclerosis.

Short-term dexamethasone treatment inhibits vein graft thickening in hypercholesterolemic ApoE3Leiden transgenic mice

OBJECTIVE

The aim of this study was to assess whether the anti-inflammatory agent dexamethasone can inhibit vein graft thickening without the occurrence of serious side effects.

METHODS

Venous interposition grafting was performed in the common carotid artery of hypercholesterolemic ApoE3Leiden transgenic mice. Mice were treated with dexamethasone (0.15 mg.kg(-1).d(-1) orally), and after 28 days, vein graft thickening was quantified.

RESULTS

Treatment with dexamethasone resulted in a significant 43% reduction in lesion area without changes in lesion composition when compared with nontreated controls. However, dexamethasone, when administered for a prolonged period of time, is known for its potentially serious side effects. To overcome these potential side effects of prolonged dexamethasone treatment, the effect of a short-term 7-day dexamethasone treatment was studied. This short dexamethasone treatment resulted in a 49% decrease of vein graft thickening at 28 days. Furthermore, it was demonstrated that dexamethasone treatment led to reduced local expression of several proinflammatory cytokines and factors in the vein grafts 24 hours after surgery. Finally, observations in mice were verified in human saphenous organ cultures. Exposure to dexamethasone for either 7 or 28 days significantly reduced intimal hyperplasia formation on cultured saphenous vein segments.

CONCLUSIONS

Short-term anti-inflammatory treatment with dexamethasone leads to a significant reduction in vein graft thickening over an extended period, possibly by the reduction of early expression of proinflammatory cytokines. This 7-day treatment minimizes the risk of unwanted side effects of long-term dexamethasone treatment and may be a new approach to prevent graft failure.