A Greek Multicentre Study Assessing the Outcome of Late Rupture After Endovascular Abdominal Aortic Aneurysm Repair

OBJECTIVE

Late rupture after endovascular aortic aneurysm repair (EVAR) for an abdominal aortic aneurysm (AAA) is an increasing complication associated with a high mortality rate. This study aimed to analyse the causes and outcomes in patients with AAA rupture after EVAR.

METHODS

A multi-institutional Greek study of late ruptures after EVAR between 2008 - 2022 was performed. Primary outcomes were intra-operative and in hospital death.

RESULTS

A total of 70 patients presented with late rupture after EVAR (proportion of ruptured EVARs among all EVARs, 0.6%; 69 males; mean age 77.2 ± 6.7 years). The mean time interval between EVAR and late rupture was 72.3 months (range 6 - 180 months). In all cases the cause of rupture was the presence of an endoleak (type I, 73%) with sac enlargement. Moreover, 34% of subjects with rupture after EVAR had been lost to follow up and 32% underwent a secondary intervention. Additionally, 57 patients (81%) were treated by conversion to open surgical repair (COSR) and the remainder by endovascular correction of endoleak (ECE). Eleven intra-operative deaths (16%) were recorded. The overall in hospital mortality rate was 41% (23% ECE vs. 46% COSR; p = .21). Of the patients who presented as initially haemodynamically stable, 23% died during hospitalisation, while the respective mortality rate for patients who presented as unstable was 78% (odds ratio [OR] 11.8, 95% confidence interval [CI] 3.6 - 39.1; p < .001). Multivariable logistic regression analysis revealed that severity of haemodynamic shock was the most significant risk factor for intra-operative (OR 7.15, 95% CI 1.58 - 32.40; p = .010) and in hospital death (OR 9.53, 95% CI 2.79 - 32.58; p < .001).

CONCLUSION

These data underline the devastating prognosis of late rupture after EVAR. Haemodynamic status at presentation was an important predictive factor for death both in the ECE and COSR groups. Rigorous follow up and prompt evaluation of an unstable patient in case of rupture after EVAR is recommended.

Paraoxonase-1: Characteristics and Role in Atherosclerosis and Carotid Artery Disease

Paraoxonase-1 (PON-1) is a calcium-dependent enzyme that is synthesized in the liver and then secreted in blood where it is bound to high density lipoprotein (HDL). PON-1 is a hydrolase with a wide range of substrates, including lipid peroxides. It is considered responsible for many of the antiatherogenic properties of HDL. PON-1 prevents low density lipoprotein (LDL) oxidation, a process that is considered to contribute to the initiation and development of atherosclerosis. PON-1 activity and levels are influenced by gene polymorphisms; of the 2 common variants, one is in position 192 (Q192R) and one in position 55 (M55L). Also, many drugs affect PON-1 activity. The role of PON-1 in carotid atherosclerosis is inconsistent. Some studies show an association of PON-1 polymorphisms with carotid plaque formation, whereas others do not. The aim of this review is to summarize the characteristics of PON-1, its interactions with drugs and its role in atherosclerosis and especially its relationship with carotid artery disease.

Aortocaval fistula: an unusual complication of ruptured abdominal aortic aneurysm

Aortocaval fistula (ACF) is a rare complication of abdominal aortic aneurysm, which erodes into the wall of the inferior vena cava, resulting in the formation of a fistula. ACF presents with various inconsistent symptoms and signs. ACF can be a diagnostic dilemma if not suspected and it is lethal if left untreated.A 60-year-old man presented with abdominal and lower back pain of sudden onset. Renal and liver functions were impaired, without signs of cardiac failure. CT angiography revealed an abdominal aneurysm rupture into the inferior vena cava. Patient underwent a successful open repair: ACF ligation from within the aneurysmal sac and an aorto-bi-iliac bypass using a Dacron graft. Renal and liver functions improved and the patient was discharged on the eighth postoperative day. A month later, the patient was fit and well with normal liver and renal functions.Despite progress made in the endovascular treatment of ACF, complications still persist with a reported endoleak rate of 50%. Open repair is still a valid method for ACF repair in patients fit to undergo laparotomy and general anaesthesia. In this case, the patient was fit and along the lack of a suitable stent graft, the vascular team performed an open repair with good results.Open repair of an ACF is a valid treatment method for patients who are fit enough to undergo laparotomy and general anaesthesia, and avoids complications related to endovascular repair, such as endoleaks.

Apolipoprotein J as a predictive biomarker for restenosis after carotid endarterectomy: a retrospective study

Carotid endarterectomy (CEA) is an effective surgical option for stroke prophylaxis in most patients. Restenosis after CEA can lead to re-intervention and adverse events, but the factors predicting restenosis are poorly understood. Apolipoprotein J (ApoJ) is considered to be a novel predictive factor of vascular restenosis and is associated with a large number of processes related to atherosclerosis and cell-cycle phases. The aim of this study was to elucidate the predictive value of Apo J in internal carotid artery (ICA) restenosis following CEA. This retrospective study examined all prospectively collected data for patients who underwent CEA at our surgical department over a 2-year period. The serum ApoJ levels of 100 patients were examined; 56 patients who underwent CEA comprised the vascular group (VG), and 44 patients who underwent minor surgery comprised the control group (CG). ApoJ samples were obtained preoperatively, 24 h after the surgical procedure and at 1, 6 and 12 months thereafter during the follow-up. The preoperative difference in ApoJ levels between the CG and VG was statistically signifcant; the mean values were 39.11±14.16 and 83.03±35.35 μg/mL, respectively. In the VG, the serum ApoJ levels were 112.09±54.40, 71.20±23.70, 69.92±25.76 and 62.25±19.17 μg/mL at postoperative day 1 and at 1, 6 and 12 months post-operatively, respectively, while the ApoJ concentrations of patients in the CG remained unchanged. Further subdivision of the VG into patients with or without restenosis revealed that restenosis patients presented signifcantly higher mean ApoJ values than non-restenosis VG patients. In summary, ApoJ seems to be an important predictor for carotid restenosis at 6 and 12 months postoperatively.

Antiplatelet Treatment in Peripheral Arterial Disease: The Role of Novel Antiplatelet Agents

BACKGROUND

Acetylsalicylic acid and clopidogrel are two antiplatelet agents currently used in the therapy of peripheral arterial disease. Cilostazol also inhibits platelet aggegration. These agents present limitations that novel antiplatelet agents may overcome.

OBJECTIVE

The aim of this manuscript is to review current data on the use of novel antiplatelet agents in peripheral arterial disease.

METHOD

An extensive search in the English medical literature has yielded a number of publications on a number of novel antiplatelet agents; atopaxar, vorapaxar, cangrelor, ticagrelor, elinogrel, and prasugrel.

RESULTS

Data on atopaxar, vorapaxar, cangrelor, ticagrelor, elinogrel and prasugrel come mainly from cardiology publications. Limitations, side effects and effectiveness of each of these agents are studied, but their use in peripheral arterial disease is limited, especially for those agents that have not still been approved for this indication. As expected, main side effect of most of these agents is haemorrhage, but other important side effects limit the use of some of these agents in specific subgroups of patients.

CONCLUSION

Novel antiplatelet agents demonstrate a range of promising characteristics, but further study and clinical trials are necessary for them to be considered safe and effective.

Use of the Nellix Endovascular Aneurysm Sealing System in Combination With Parallel Grafts for the Treatment of a Symptomatic Type V Thoracoabdominal Aortic Aneurysm

PURPOSE

To report endovascular treatment of a symptomatic type V thoracoabdominal aortic aneurysm (TAAA) using the combined techniques of endovascular aneurysm sealing and parallel stent-grafts.

CASE REPORT

A 70-year-old man was referred with a symptomatic type V TAAA. The Nellix EndoVascular Aneurysm Sealing (EVAS) System was used in combination with 2 chimney grafts for the celiac artery (CA) and the superior mesenteric artery (SMA); one periscope graft perfused the right renal artery. Completion angiography showed exclusion of the aneurysm and patency of all 3 parallel grafts but occlusion of the left renal artery (LRA) due to unintentional coverage of its ostium by the Nellix endobags. Antegrade catheterization of the LRA failed, requiring implantation of an aortorenal vein bypass. The postoperative course was complicated by acute kidney injury. Imaging at 6 months showed sustained exclusion of the aneurysm, patency of the CA and SMA parallel grafts and left aortorenal bypass but occlusion of the right renal artery periscope graft. Serum creatinine at 6 months was 1.5 mg/dL.

CONCLUSION

The combination of EVAS with parallel grafts for preservation of the visceral vessels may be a feasible technique to treat selected TAAAs in the acute setting when other options are not applicable.

Endovascular Repair of Traumatic Isthmic Ruptures: Special Concerns

Injury of the aortic isthmus is the second most frequent cause of death in cases of blunt traumatic injury. Conventional open repair is related to significant morbidity and mortality. Thoracic endovascular aortic repair (TEVAR) has increasing role in traumatic isthmic rupture, as it avoids the thoracotomy-related morbidity, aortic cross clamping, and cardiopulmonary bypass. Additionally to the technical difficulties of open repair, multi-trauma patients may not tolerate the manipulations necessary to undergo open surgery, due to concomitant injuries. TEVAR is a procedure easier to perform compared to open surgery, despite that a considerable degree of expertise is necessary. Direct comparison of the two methods is difficult, but TEVAR appears to offer better results than open repair in terms of mortality, incidence of spinal cord ischemia, renal insufficiency, and graft infection. TEVAR is related to a-statistically not significant-trend for higher re-intervention rates during the follow-up period. Current guidelines support TEVAR as a first-line repair method for traumatic isthmic rupture. Certain specific considerations related to TEVAR, such as the timing of the procedure, the type and oversizing of the endograft, heparinization during the procedure, the necessity of cerebrospinal fluid drainage, type of anesthesia, and the necessary follow-up strategy remain to be clarified. TEVAR should be considered advantageous compared to open surgery, but future developments in endovascular materials, along with accumulating long-term clinical data, will eventually improve TEVAR results in traumatic aortic isthmic rupture (TAIR) cases. This publication reviews the role, outcomes, and relevant issues linked to TEVAR in the repair of TAIR.

Three-Stage Esophagectomy Combined with Abdominal Aortic Aneurysm Repair: First Case in the Literature

The purpose of this report is to describe the synchronous surgical treatment of an abdominal aortic aneurysm (AAA) with concomitant esophageal cancer with a 3-stage esophagectomy, a real management challenge especially in establishing the therapeutic priorities and the ideal treatment approach. A 65-year-old male was referred for treatment in our hospital with the diagnosis of AAA. He complained of general fatigue, weight loss, and intermittent dysphagia. Contrast-enhanced computed tomography and upper endoscopy showed the AAA and a large gastroesophageal junction tumor, respectively. Considering his age and the absence of severe comorbidities, he underwent 3-stage esophagectomy combined with AAA repair. The patient had an uneventful postoperative course and was discharged on the 15th postoperative day. He was offered adjuvant chemotherapy and remains free of disease and with a patent aortic graft at 18 months of follow-up.

Aortic Graft Infection: Graphene Shows the Way to an Infection-Resistant Vascular Graft

Aortic graft infection is a potentially lethal complication of open and endovascular repair of aortic aneurysms. Graphene is the only existing two-dimensional material, and its unique structure gives graphene and its derivatives a plethora of original characteristics. Among other characteristics, graphene demonstrates bacteriostatic and bactericidal effects that could potentially resolve the problem of graft infection in the future. Data already exist in literature supporting this antibacterial effect of graphene oxide and reduced graphene oxide. Combining these materials with other substances enhances the antibacterial effect. Additionally, it looks feasible to expect antibiotic-delivering graphene-based graft materials in the future. Based on already published data, we could conclude that regarding graphene and its derivatives, the blessing of bactericidal effect comes with the curse of human cells toxicity. Therefore, it is important to find a fine balance between the desired antibacterial and the adverse cytotoxic effect before graphene is used in graft materials for humans.

Is volume important in aneurysm treatment outcome?

Several studies have suggested that surgical procedures performed at high-volume centers may result in superior outcome. Technically more demanding procedures such as aortic aneurysm repair appear to demonstrate a stronger relationship with volume. The present chapter reviewed the literature using the MEDLINE database to identify studies investigating the effect of volume in aortic aneurysm repair outcomes. The great majority of studies identified shows an advantage for high-volume hospitals with regard to perioperative mortality of abdominal (AAA), thoracic (TAA) and thoracoabdominal (TAAA) aortic aneurysm repair. A similar advantage is shown for high-volume surgeons. The volume advantage appears to be less evident for simple endovascular procedures (EVAR & TEVAR), compared to more complex endovascular (F/BEVAR) and open surgical procedures. Superior outcomes observed in high-volume hospitals are not only explained by increased surgeons' experience, but importantly also by a more effective management of intra- and postoperative complications. Confounding factors to be taken into account are the timing of the studies in relation to positive evolution of outcomes in several high-risk procedures, and patient cohorts selected in regions with very low- and very high-volume hospitals only.

Patent Femoropopliteal Vein Bypass Graft 45 Years After Implantation

Patency of femoropopliteal vein bypass above the knee has been estimated between 69% and 77% at 5 years. This article reports a case of a patent femoropopliteal vein bypass 45 years after implantation without any reintervention. The morphologic alterations observed after 45 years at this vein bypass graft are additionally discussed.

Carotid Stenting with Cerebral Protection: First Clinical Experience Using the PercuSurge GuardWire System

Purpose:

To study the feasibility and safety of carotid angioplasty and stenting using a new cerebral protection device that temporarily occludes the distal internal carotid artery (ICA).

Methods:

Forty-eight high-risk patients (39 men, mean age 69.1 ± 8 years, range 54 to 86) with 53 ICA stenoses underwent percutaneous angioplasty and stenting via the femoral approach under cerebral protection afforded by a 0.014-inch GuardWire balloon occlusion device. Mean stenosis was 82.1% ± 9.65% (range 70 to 96) and mean lesion length was 16.0 ± 7.5 mm (range 6 to 50). Thirty-three (62%) lesions were calcified, and 38 (72%) were ulcerated. Thirty-two (60%) of the lesions were asymptomatic. With the occlusion balloon inflated in the distal ICA, the lesion was dilated and stented. The area was cleaned by aspiration and flushed via an aspiration catheter advanced over the wire. Blood samples were collected from the external carotid artery (ECA) and analyzed to measure the size and number of particles collected. Computed tomography and neurological examinations were performed the day after the procedure.

Results:

Immediate technical success was achieved in all patients with the implantation of 38 Palmaz stents, 8 Expander stents, and 11 Wallstents. Carotid occlusion was well tolerated in all patients but 1 who had multiple, severe carotid lesions and poor collateralization. Mean cerebral flow occlusion time was 346 ± 153 seconds during predilation and 303 ± 143 seconds during stent placement. Total mean flow occlusion time was 542 ± 243 seconds. One immediate neurological complication (transient amaurosis) occurred in a patient who had an anastomosis between the external carotid (EC) and ICA territories. Debris was removed in all patients with a mean 0.8-mm diameter catheter.

Conclusion:

Cerebral protection with the GuardWire device is easy, safe, and effective in protecting the brain from cerebral embolism. Larger studies are warranted.

Hybrid Treatment of Large Brachial Artery Pseudoaneurysms

BACKGROUND

Conventional surgical treatment of brachial artery pseudoaneurysms (BAPs) includes aneurysm excision/opening and subsequent arterial reconstruction with different options depending on the extent of the arterial deficit. Endovascular repair of BAPs with stent grafting has also been reported but published experience remains limited. In this report, we present our experience with a novel hybrid approach consisting of primary endovascular aneurysm exclusion with a stent graft and subsequent open surgical evacuation of pseudoaneurysm content for decompression of adjacent structures.

METHODS

This study included all patients who underwent hybrid repair of a BAP within the period 2005-2014 in our institution. Data were collected retrospectively.

RESULTS

During the study period a total of 5 patients with iatrogenic BAPs were treated. Mean BAP diameter was 58 ± 4.9 mm. Technical success was 100%. Thirty-day mortality was null. No major perioperative complications were noted. Hand ischemia and neurological symptoms were reversed in all patients after the procedure. During follow-up (median 24 months, range 6-60 months) all stent grafts remained patent and no aneurysm relapse was noticed. No signs of stent-graft infection were noticed in any of the patients and no reintervention was needed.

CONCLUSIONS

Primary endovascular exclusion of BAPs with a stent graft followed by surgical evacuation of pseudoaneurysm sac content is associated with good early and mid-term results in this limited experience. Larger patient cohorts are required for further evaluation of this technique.

Oxidative Stress and Total Antioxidant Status During Internal Carotid Artery Clamping with or without Shunting: An Experimental Pilot Study

Background

The exact role of shunting during carotid endarterectomy remains controversial and unclear. The aim of this experimental study was to investigate to what degree carotid clamping may induce changes in the cerebral oxidative status and to focus on the relation of these changes with shunt insertion.

Material/Methods

Forty New-Zealand rabbits were randomized into 4 groups: group 1 classifying animals with carotid shunt and patent contralateral carotid artery; group 2 shunt and occlusion of the contralateral carotid artery; group 3 no-shunt and patent contralateral carotid artery; and group 4 no-shunt and occlusion of the contralateral carotid artery. Blood samples were collected from the ipsilateral internal jugular vein, immediately after carotid clamping (time 0), and then at 5, 10, 15, 30, and 60 minutes afterwards. Evaluation of oxidative stress was accomplished by measuring the lag-time, representing the initial phase of oxidation, rate of accumulation (RA), showing concentration of free oxygen radical and total antioxidant status (TAS) representing antioxidant composition of serum.

Results

Lag-time was significantly different in time points 0, 30 and 60 minutes within each different group. TAS was significantly different in time points 0, 15 and 60 min and RA in time points 0, 5, 10 and 60 min within each different group. 60 minutes after carotid clamping, the rate of accumulation as well as lag-time and TAS were increased in all groups, independently of using or not shunting or the presence of contralateral occlusion. After comparing groups 1, 2 and 3 regarding lag-time, TAS and RA, we did not find statistical difference among the groups at any time point. On the contrary, groups 1, 2 and 3 did show significantly different values comparing to group 4 after 60 min of occlusion.

Conclusions

Our experimental work based on cerebral metabolism found a significantly higher oxidative stress in models with contralateral carotid occlusion. The use of shunt in all other models did not have any influence on oxidative response. Future human studies should focus on the relation of oxidative status and shunt insertion to determine the benefit of selective or routine shunting during CEA.

Common iliac and hypogastric aneurysms: open and endovascular repair

Currently, there are a variety of open surgical, endovascular, and hybrid options to treat iliac artery aneurysms (IAA). Anatomy of the common iliac artery (CIA) with regard to proximal and distal neck, involvement of the iliac bifurcation, and choice to preserve the ipsilateral internal iliac artery (IIA) all play a role in the decision process towards the preferred treatment method. This manuscript describes the available open surgical and endovascular techniques for the treatment of IAA. Indications, advantages and limitations, and outcomes of each technique are discussed.

Treatment paradigms for ductus arteriosus aneurysms in adults

We report two symptomatic cases of ductus arteriosus aneurysm (DDA) in adults treated in our department over a 5-years period. One patient underwent an open off-pump surgical procedure, while the second one was treated with partial aortic arch debranching and endovascular stent-grafting. DDA in adults is an uncommon condition and can present with rupture, hoarseness or symptoms of airway obstruction. Although indications for intervention are not clearly established, most authors advocate that DDAs should be treated regardless of their size, to avoid the risk of rupture, while others reserve intervention for symptomatic patients. We report on the management of these patients and provide an updated review of the current literature.

The effect of revascularization procedures on healing of mixed arterial and venous leg ulcers

AIM

The optimal management of venous leg ulcers in patients with concomitant peripheral artery disease (PAD) remains unclear. The aim of the present study was to evaluate the effectiveness of revascularization procedures in healing of the ulcers of mixed etiology.

METHODS

During a 6-year period a total of 20 patients with evidence of chronic venous insufficiency, impaired arterial perfusion (ABI<0.75) and active leg ulcer were treated. Patients with moderate PAD (0.5<ABI<0.75) were treated conservatively with modified compression and were considered for revascularization if the ulcer did not heal, while those with severe PAD (ABI<0.5) underwent revascularization.

RESULTS

Eleven out of seventeen (64.7%) limbs with moderate arterial disease showed a significant healing progress after modified compression and healed at an average time of 24.7±3.1 weeks, while the other 6 limbs (35.3%) failed to improve underwent revascularization and healed at an average time of 16±2.6 weeks. Three limbs with severe arterial disease underwent revascularization and healed at an average time of 17.6±2.5 weeks. Overall the nine arterial interventions had a 100% technical success rate, while ABI improved from 0.54±0.07 to 0.94±0.04 after the intervention. The 30-day mortality was null. Healing time in patients treated with revascularization was significantly lower compared to those treated conservatively (16.6±2.6 weeks vs. 24.7±3.2 weeks, P<0.001). During the follow-up period (48.7±14.3 months), there were 9 ulcer recurrences, 6 in the group of conservative treatment and 3 in the group of revascularization. No significant difference in recurrences between the two groups (log rank=0.772, P=0.38) was demonstrated.

CONCLUSION

A protocol-driven therapeutic strategy that includes a revascularization procedure as a therapeutic option in patients with ulcers of mixed etiology may be beneficial. Based on the current data, it is essential the therapeutic strategy to be individualized by including an overall risk assessment accounting for comorbidities of the patient and the risk of the procedure.

Common carotid artery occlusion treatment: revealing a gap in the current guidelines

OBJECTIVE

To review the literature on the management of common carotid artery occlusion (CCAO).

METHODS

A review of English-language medical literature from 1965 to 2012 was conducted using the PubMed and EMBASE databases to find all studies involving management of CCAO. The search identified 21 articles encompassing 146 patients/arteries (73.2% men; mean age 65 ± 6.9 years).

RESULTS

The majority of the patients (93.8%) were symptomatic. Most of the patients (61.5%) had ipsilateral internal carotid artery (ICA) and external carotid artery (ECA) patent, while an occluded ICA and a patent ECA were found in 26.6% of the patients. Eighty per cent of the patients treated underwent a surgical bypass procedure, with the subclavian artery as the most common inflow vessel (64.1%). During the first 30 days of the procedure two strokes (1.5%) were reported. During a follow-up period spanning an average of 25.6 ± 11.2 months nine patients (6.6%) experienced a clinical cerebrovascular event. Seven restenoses (5.1%) and two reocclusions (1.5%) also occurred-eight after open surgical and one after endovascular repair.

CONCLUSION

The necessity to intervene to a CCAO remains controversial. This review shows that open surgical management of symptomatic CCA occlusive disease is a safe, durable, and effective therapeutic strategy with low perioperative cerebrovascular morbidity.

Late renal artery occlusion following endovascular repair of abdominal aortic aneurysm: a possible complication of mural thrombus formation within aortic endografts

Mural thrombus formation within aortic endoprostheses has been described to occur in up to one-third of aortic endografts depending on the device type. Data regarding the clinical significance of such a phenomenon are scarce, but in most cases it is considered to be clinically innocent. The authors describe a rare case of late renal artery occlusion due to intraprosthetic thrombus formation and extension into the right renal orifice 30 months after endovascular abdominal aortic aneurysm repair. Additionally, a brief literature review regarding the incidence and natural history of mural thrombotic deposits within aortic endografts is also conducted.

Telomerase expression on aortic wall endothelial cells is attenuated in abdominal aortic aneurysms compared to healthy nonaneurysmal aortas

OBJECTIVE

Linear chromosomes carry specific DNA structures at their ends called telomeres. The latter shorten with each successive cell division making their length a marker of cell age. Telomerase prevents such telomere attrition by adding back telomeric repeats at the telomere ends, thus playing an important role in cell aging. On the other hand, an abdominal aortic aneurysm (AAA) represents an age-related degenerative disorder. The aim of the present study was to investigate a potential correlation of telomerase expression with AAA formation.

METHODS

Aortic wall tissue samples were collected from 49 patients (mean age, 63.8 ± 4.4 years) with AAAs during open elective repair and from 24 deceased organ donors as controls (mean age, 60.5 ± 3.9 years). Telomerase expression on endothelial cells was detected by immunohistochemistry. Associations of telomerase positivity with AAAs and epidemiologic and clinical variables were investigated.

RESULTS

Telomerase expression was significantly decreased in patients with AAAs (11 of 49; 22.4%) compared to controls (19 of 24; 79.2%; P < .001). This association persisted after adjustment for age, gender, coronary artery disease (CAD), hypercholesterolemia, hypertension and smoking (odds ratio, 0.47; 95% confidence interval, 0.14-0.58; P < .01.).

CONCLUSION

Patients with AAAs have attenuated telomerase endothelial expression compared to controls, implying a protective role of telomerase against AAA formation. Further investigation of pathways involved in vascular aging may contribute to elucidation of AAA pathogenetic mechanisms.

Statin treatment is associated with reduced toll-like receptor 4 immunohistochemical expression on carotid atherosclerotic plaques: a novel effect of statins

Toll-like receptor 4 (TLR4) has been recently implicated in inflammatory pathways involved in carotid plaque destabilization. Given that statins have plaque stabilization and inflammation reduction effects, we investigated whether TLR4 expression on carotid atherosclerotic plaques correlates with statin intake. Carotid atherosclerotic plaques were obtained on 140 patients (preoperative statin intake, n = 70). TLR4 immunohistochemical expression was investigated in endothelial cells (ECs), macrophages (MACs) and smooth muscle cells (SMCs) of carotid atheroma. TLR4 positivity, over-expression and intensity of immunostaining were compared in statin versus no-statin users. The results of this study showed that statin users had a significantly lower expression of TLR4 in ECs (P = 0.02, 0.001, 0.006 for TLR4 positivity, increased intensity and over-expression, respectively). Similarly, TLR4 positivity was less pronounced in carotid plaque MACs of statin users (P = 0.03). No carotid specimen with increased EC TLR4 intensity or over-expression was observed among statin users. The prevalence of any cerebrovascular accident was 61.4% in the 'no statin' versus 18.6% in the 'statin' group (odds ratio for statin use: 0.14, 95% CI: 0.07-0.31, P < 0.001). In conclusion, statin treatment is associated with attenuated TLR4 expression on human carotid atherosclerotic plaques and a reduced risk of carotid-related cerebrovascular events. TLR4 may potentially mediate statins' plaque stabilization effects. Further investigation is necessary.

Insight into pain-inducing and -related gene expression: a challenge for development of novel targeted therapeutic approaches

The multidimensional issue of pain in relation to the need for efficient treatment has been the focus of extensive research. Gaining insight into the molecular mechanisms of pain and identifying specific genes and proteins as possible drug targets is strongly required considering that not all patients can be adequately treated with the currently available drugs. This up-to-date review aimed to summarize the findings of recent proteomic and genomic approaches in different types of pain to comment on their potential role in pain signaling pathways and to evaluate their possible contribution to the development of novel and possibly more targeted pain therapeutic strategies. Although pain treatment strategies have been greatly improved during the past century, no ideal targeted pain treatment has been developed. The development of modern and accurate platforms of technology for the study of genetics and physiology of pain has led to the identification of an increased number of altered genes and proteins that are involved in pain-related pathways. Through genomics and proteomics, pain-related genes and proteins, respectively, may be identified as diagnostic markers or drug targets improving therapeutic strategies. Furthermore, such molecular mediators of pain may reveal novel strategies for individualized pain management. The utilization of unique experimental approaches (through specific animal models) as well as powered genetic association studies conducted on appropriate populations is more than essential.

The role of carotid plaque echogenicity in baroreflex sensitivity

OBJECTIVE

The baroreflex sensitivity is impaired in patients with carotid atherosclerosis. The purpose of our study was to assess the impact of carotid plaque echogenicity on the baroreflex function in patients with significant carotid atherosclerosis, who have not undergone carotid surgery.

METHOD

Spontaneous baroreflex sensitivity (sBRS) was estimated in 45 patients with at least a severe carotid stenosis (70%-99%). sBRS calculation was performed noninvasively, with the spontaneous sequence method, based on indirectly estimated central blood pressures from radial recordings. This method failed in three patients due to poor-quality recordings, and eventually 42 patients were evaluated. After carotid duplex examination, carotid plaque echogenicity was graded from 1 to 4 according to Gray-Weale classification and the patients were divided into two groups: the echolucent group (grades 1 and 2) and the echogenic group (grades 3 and 4).

RESULTS

Sixteen patients (38%) and 26 patients (62%) were included in the echolucent and echogenic group, respectively. Diabetes mellitus was observed more frequently among echolucent plaques (χ(2) = 8.0; P < .004), while those plaques were also more commonly symptomatic compared with echogenic atheromas (χ(2) = 8.5; P < .003). Systolic arterial pressure, diastolic arterial pressure, and heart rate were similar in the two groups. Nevertheless, the mean value of baroreflex sensitivity was found to be significantly lower in the echogenic group (2.96 ms/mm Hg) compared with the echolucent one (5.0 ms/mm Hg), (F [1, 42] = 10.1; P < .003).

CONCLUSIONS

These findings suggest that echogenic plaques are associated with reduced baroreflex function compared with echolucent ones. Further investigation is warranted to define whether such an sBRS impairment could be responsible for cardiovascular morbidity associated with echogenic plaques.

ICU transfer after elective abdominal aortic aneurysm repair can be succesfully reduced with a modified protocol. A fourteen year experience from a University Hospital

AIM

To compare different selective criteria for Internal Care Unit (ICU) admission in two different timeframes, after abdominal aortic aneurysm (AAA) repair. A retrospective audit of acquired data was performed.

METHODS

During a period of fourteen years (1994-2008), 1152 patients underwent an elective open operation for infrarenal abdominal aortic aneurysm, in our department. Six hundred and two patients (Group A) were treated in the period January 1994-January 2003, and 550 patients (Group B) between January 2003 and August 2008. Postoperatively, all patients were transferred to postanesthesia unit (PAU). After a 2 hours period of close observation, they were transferred either to the ICU or to the surgical ward, according to certain selective criteria (SC). In group A we used SC-A, for admission to an ICU, and in group B we used new, stricter, criteria (SC-B). Thirty-day mortality and morbidity, elective admissions to ICU, rate of subsequent ICU admission, from ward to ICU, and the mean hospital and ICU length of stay, were compared between the two groups.

RESULTS

The use of SC-B resulted in a significant reduction of elective admissions to ICU (3.1% vs 8.5%, P<0.001). Nevertheless, the portion of patients, which were transferred with a severe postoperative complication from the ward to ICU, remained similar between the two groups (1.1% vs 0,9%, in group A and B, respectively). All other endpoints were similar in both groups.

CONCLUSION

Modifying the protocol of ICU transfer, after elective abdominal aortic aneurysm repair, we can reduce the number of patients requiring ICU, without compromising patients' safety.

Retroperitoneal tumor invasion of the inferior vena cava. A single-centre experience in tumor thrombectomy

BACKGROUND AND AIM

Radical surgical treatment improves survival in patients suffering from retroperitoneal tumors with co- existing inferior vena cava thrombus. The extraction excision can be performed through many techniques such as liver mobilization which is performed in liver transplantation procedures.

METHODS

During 2000-2007, 11 patients with retroperitoneal tumors and inferior vena cava thrombus were surgically treated in our department. Classification of the thrombus was defined as suggested by Neves and Zinke. All patients were categorized as level I or level II. In all cases a transabdominal approach, liver mobilization and extraction of the thrombus by milking down or Fogarty catheter were used.

RESULTS

No peri-operative mortality was observed. One case of pulmonary embolisation was conservatively treated. One patient presented recurrence 6 months after the procedure.

CONCLUSIONS

The use of liver transplantation techniques in the surgical management of retroperitoneal tumors with inferior vena cava thrombus, is a safe procedure that improves the survival of these patients.

Clinical implication of plasma neutrophil gelatinase-associated lipocalin (NGAL) concentrations in patients with advanced carotid atherosclerosis

BACKGROUND

Neutrophil gelatinase-associated lipocalin (NGAL) is well established as an early and specific biomarker of kidney disease. Recent evidence further suggests that NGAL may play a crucial role in vascular remodeling and plaque instability during the development of atherosclerosis.

METHODS

Plasma NGAL concentrations measured using a solid-phase enzyme-linked immunosorbent assay (ELISA) were correlated with medical history, risk factors and medication intake in 141 patients with advanced carotid atherosclerotic lesions who underwent carotid endarterectomy for vascular repair.

RESULTS

Plasma NGAL concentrations were associated with patient age (R(s)=0.2055, p=0.0144), plasma homocysteine (R(s)=0.4274, p<0.00001) and serum creatinine (R(s)=0.4640, p<0.00001) concentrations and estimated glomerular filtration rate (eGFR) (R(s)=-0.4911, p<0.00001). Hypertensive patients, as well as those receiving therapy with angiotensin converting enzyme (ACE) inhibitors, presented with significantly enhanced plasma NGAL concentrations when compared to normotensive (p=0.0341) patients and those not treated (p=0.0004). Enhanced NGAL concentrations did not meet statistical significance for patients with advanced stenosis grade (p=0.0971) or a history of peripheral artery disease (p=0.0827). Multiple regression analysis identified homocysteine, creatinine, eGFR and treatment with ACE inhibitors (p=0.0019, <0.00001, 0.0005 and 0.0219, respectively) as independent predictors of NGAL concentration.

CONCLUSIONS

Plasma NGAL concentrations were associated with patient age, hypertension, eGFR, creatinine and homocysteine concentrations and therapy with ACE inhibitors. The role of NGAL in the development of atherosclerosis needs to be further explored taking into consideration the uncontrolled effect of renal disease in atherosclerotic patients with multiple risk factors.

Toll-like receptors: a novel target for therapeutic intervention in intestinal and hepatic ischemia-reperfusion injury?

IMPORTANCE OF THE FIELD

Toll-like receptors (TLRs) are transmembrane proteins that act mainly as sensors of microbes, orchestrating an organism's defense against infections, while they sense also host tissue injury by recognizing products of dying cells. Ischemia-reperfusion injury (IRI) represents one of these tissue damage states in which TLR-mediated mechanisms might be implicated.

AREAS COVERED IN THIS REVIEW

The most recent data on TLR signaling and the latest knowledge regarding the involvement of TLRs in the pathogenesis and progression of intestinal and hepatic IRI are presented. The potential effectiveness of TLR-modulating therapy in intestinal and liver IRI is also analyzed.

WHAT THE READER WILL GAIN

A comprehensive summary of the data suggesting TLR involvement in intestinal and hepatic IRI. Knowledge required for developing TLR modulation strategies against intestinal and hepatic IRI.

TAKE HOME MESSAGE

TLRS play a significant role in both intestinal and hepatic IRI pathophysiology. Better understanding of TLR involvement in such processes may enable the invention of novel TLR-based therapies for IRI in the intestine and liver.

Toll-like receptor 4 immunohistochemical expression is enhanced in macrophages of symptomatic carotid atherosclerotic plaques

BACKGROUND

A growing body of evidence supports a role for Toll-like receptor 4 (TLR4), a primary receptor of the innate immune system, in atherosclerosis initiation and progression. Carotid atheroma macrophages (MACs) and smooth muscle cells (SMCs) express TLR4; nevertheless, correlations with epidemiological and clinical variables and especially cerebrovascular symptomatology remain unsettled.

METHODS

Carotid atherosclerotic plaques were obtained by standard carotid endarterectomy on 157 patients with carotid artery disease (84 asymptomatic - 73 symptomatic). TLR4 expression in MACs and SMCs of carotid atheroma was detected by immunohistochemistry techniques. TLR4 positivity, overexpression and intensity of immunostaining in MACs and SMCs were correlated with cerebrovascular symptomatology, epidemiological and clinical variables.

RESULTS

MAC TLR4 positivity was noted in 129 (82.2%) patients. Patients receiving statins had significantly lower TLR4 expression. Rates of MAC TLR4 positivity were higher among symptomatic patients (odds ratio, OR = 5.1; 95% confidence interval, CI = 1.8-14.3; p < 0.001); the association was stronger for transient ischemic attacks. TLR4 overexpression was also significantly enhanced among symptomatic patients (OR = 2.3; 95% CI = 1.02-5.03; p < 0.05). No correlations were detected between SMC TLR4 expression and cerebrovascular symptoms. In multivariate models adjusting for age, gender, body mass index, hyperlipidemia and smoking, MAC TLR4 positivity was associated with a cerebrovascular event during the last 6 months (OR = 4; 95% CI = 1.2-13.3; p = 0.02).

CONCLUSIONS

Symptomatic carotid artery plaques are characterized by increased expression of TLR4 in macrophages supporting a potential role for TLR4 in the pathophysiology and clinical presentation of cerebrovascular disease. Further investigation is warranted.

Endovascular repair of a persistent sciatic artery aneurysm

Persistent sciatic artery (PSA), a persistent embryologic continuation of the internal iliac artery, represents a rare yet clinically important vascular anomaly. PSA is prone to aneurysmal change, which can subsequently lead to distal embolization, sciatic neuropathy, or rupture. The conventional surgical treatment of PSA aneurysms is commonly complex and carries the risk for sciatic nerve damage. We report herein the successful endovascular management of a PSA aneurysm and postaneurysmal stenosis with the use of two overlapping self-expanding stent-grafts via a contralateral transfemoral approach. Additionally, a review of the literature regarding the treatment of these unusual peripheral aneurysms is provided.

Enhanced TLR4 endothelial cell immunohistochemical expression in symptomatic carotid atherosclerotic plaques

BACKGROUND AND PURPOSE

Toll-like receptor-4 (TLR4) has been linked to the pathogenesis of atherosclerosis. Carotid atheroma endothelial cells (ECs) express TLR4, nevertheless correlations with cerebrovascular symptomatology, epidemiological and clinical variables remain unresolved.

METHODS

Carotid atherosclerotic plaques were obtained by standard carotid endarterectomy from 157 patients with carotid artery disease (84 asymptomatic - Group A, 73 symptomatic - Group B). TLR4 expression was detected by immunohistochemistry and TLR4 positivity, overexpression and intensity of immunostaining in ECs were correlated with cerebrovascular symptomatology, epidemiological and clinical variables.

RESULTS

A significant association was found between TLR4 positivity in ECs and the occurrence of any cerebrovascular event (overall response (OR): 2.85, 95% CI 1.33 - 6.11, p = 0.009). TLR4 overexpression and staining intensity in ECs were both significantly enhanced in symptomatic patients (p < 0.0001 and p = 0.003, respectively). These associations were stronger for the occurrence of a major cerebrovascular accident (CVA) compared with a transient ischemic attack (TIA) or amaurosis fugax. TLR4 expression in ECs was less prominent in statin users (OR: 0.25, 95%CI 0.1 - 0.58, p = 0.001], while it was enhanced in restenotic plaques compared with primary atherosclerotic lesions (p = 0.012).

CONCLUSIONS

TLR4 expression in ECs of carotid atheroma was enhanced in symptomatic patients with most commonly 'unstable' - 'more prone to rupture' carotid plaques.

Toll-like receptors in liver ischemia reperfusion injury: a novel target for therapeutic modulation?

BACKGROUND

There is increasing evidence that Toll-like receptors (TLRs) sense host tissue damage by engaging with endogenous ligands. TLRs are considered to be involved in many primarily non-immune-related diseases. Hepatic ischemia reperfusion injury (IRI) represents one of these disorders.

OBJECTIVE

To present the latest findings supporting the involvement of TLRs in liver IRI and to explore their role as potential targets for therapeutic intervention.

METHODS

A review of the literature summarizing the latest advances in TLR signaling, the role of TLRs in each hepatic cell population and the involvement of TLRs in the pathophysiology of hepatic IRI. The potential role of TLR-targeting treatment strategies in liver IRI is discussed.

CONCLUSIONS

Recent experimental evidence suggests that TLR activation on Kupffer cells provides the triggering signal for pro-inflammatory responses that lead to liver IRI. Modulating TLR signaling could have a beneficial effect in patients with liver IRI.

Correlation of calcified carotid plaques detected by panoramic radiograph with risk factors for stroke development

OBJECTIVES

The aim was to evaluate whether patients with calcifications in the carotid region detectable by panoramic radiograph differ in the prevalence of risk factors for stroke development compared with those without calcifications.

STUDY DESIGN

Forty consecutive individuals suffering from proven carotid artery atherosclerotic occlusive disease were submitted to carotid endarterectomy. Seventeen patients were symptomatic at the time of referral, having suffered at least 1 episode of ischemic cerebral event during the preceding 6 months, mainly transient ischemic attacks or amaurosis fugax, and the remaining 23 patients were asymptomatic and the diagnosis was reached during a thorough investigation of coexisting coronary or peripheral vascular disease. Preoperatively, all patients had undergone panoramic radiograph examination, as the presurgical protocol commanded. Based on the panoramic radiograph results, patients in whom calcifications were detected either unilaterally (n = 10) or bilaterally (n = 18) constituted group A (n = 28) and patients in whom no calcifications were detected constituted group B (n = 12) of this study.

RESULTS

Univariate analysis among several risk factors for stroke development between the 2 groups of patients disclosed a stastistically significant lower incidence of diabetes mellitus (P = .005) but a higher incidence of symptomatic plaques (P < .030) in the group of patients with detectable calcifications in the panoramic radiograph.

CONCLUSION

Patients with calcified carotid plaques detectable by panoramic radiography are more likely to have suffered cerebrovascular events. Therefore, patients with detectable carotid plaque in panoramic radiographs require referral to their physician for further investigation.

Stent-graft repair of isolated iliac aneurysms with wide or ectatic necks with use of inverted zenith device legs

Although there is considerable experience in the management of iliac artery aneurysms (IAAs) accompanying abdominal aortic aneurysms, less is known about endovascular management of isolated IAAs. The distal landing zone can be secured if necessary by extending the graft to the external iliac artery, but the proximal landing zone remains a challenging issue, on which technical success is dependent. The present report describes a novel technique for endovascular management of isolated IAAs with wide proximal necks for which no commercially available grafts with fitting sizes exist: inversion of the iliac leg of a Zenith device.

Toll-like receptor modulation: a novel therapeutic strategy in cardiovascular disease?

BACKGROUND

Toll-like receptors (TLRs) have been recently recognised as primary receptors in the innate immune system. Apart from initiating a prompt immune response against invading pathogens, TLRs are also considered to be an important link between innate immunity, inflammation and a variety of clinical disorders, including cardiovascular diseases. TLR signalling manipulation with novel drugs could offer important opportunities for cardiovascular disease modification.

OBJECTIVE

To present the latest knowledge supporting the involvement of TLRs in the pathogenesis and progress of cardiovascular diseases and explore the role of TLRs as potential targets for therapeutic intervention in cardiovascular territory.

METHODS

A review of the literature documenting implication of TLR signalling in cardiovascular disorders. Current progress in TLR-targeting drug development and the potential role of such a treatment strategy in cardiovascular disorders are discussed.

CONCLUSIONS

A growing body of evidence supports a role for TLRs in cardiovascular disease initiation and progression. Altering TLR signalling with novel drugs could be a beneficial therapeutic strategy for patients with cardiovascular disorders.

The potential role of primary care in the management of common ear, nose or throat disorders presenting to the emergency department in Greece

BACKGROUND

The aim of this study was to assess the prevalence of common ear, nose or throat (ENT) conditions presenting to emergency departments that could be managed by a primary healthcare system Method: Between January 2001 and January 2006 a total of 33 792 patients attended the ENT emergency department of one hospital. All cases were included in this retrospective study. The registry of ENT emergency department was analysed; age, sex and clinical diagnosis were tabulated. All patients were evaluated by a specialist. Classification of the cases was based on the main symptom seeking care.

RESULTS

A total of 33 792 patients visited the otorhinolaryngology emergency department. Of these, 17 775 patients (52.6%) were men and 16 017 (47.4%) were women. Over 40% of the cases were classified in eight major groups of diagnosis. Acute tonsillitis (12.5%) and acute pharyngitis (11.4%) followed by acute otitis externa (5.9%) were the most common causes of all ENT emergency department visits. The admission rate was 1.2 % and only 0.6% (84) of patients were referred to other specialties.

CONCLUSION

Most common ENT disorders presenting to the emergency department in Greece could be managed at the level of primary health care. Incorporating ENT expertise into educational and training programmes of general practitioners may be successful in managing ENT problems in primary care in future.