Bilateral Endograft Limb Occlusion after Endovascular Aortic Repair: Predictive Factors of Occurrence.

BACKGROUND: Bilateral limb occlusion after endovascular aortic repair (EVAR) is relatively uncommon. The aim of this study was to investigate the incidence of bilateral endograft limb occlusion after EVAR and identify potential anatomical predictive factors of occurrence. METHODS: A total of 579 patients underwent elective EVAR for abdominal aortic aneurysm between January 2010 and December 2015. All patients presenting with unilateral and bilateral occlusions were prospectively analyzed. A group of patients who underwent EVAR but did not present with endograft limb occlusion were matched for sex, age, and commercial type of endograft and were used as controls. RESULTS: Overall, 21 (3.6%) patients were complicated with unilateral endograft limb occlusion, whereas 8 (1.4%) of them presented with sequential (in different time) bilateral limb occlusion. We found that iliac artery angulation ≥60°, iliac perimeter calcification ≥50%, and endograft oversizing in the common iliac artery of more than 15% had the same impact and could equally result in limb occlusion. We coded the variables angle, calcification, and endograft limb oversizing of the common iliac artery with a score from 0 to 2 as follows: (1) 0: angle <60° in both limbs, 1: angle ≥60° in one limb, 2: angle ≥60° in both limbs; (2) 0: calcification <50%: in both limbs, 1: calcification ≥ 50%: in one limb, 2: calcification ≥ 50%: in both limbs; and (3) 0: endograft limb oversizing <15%, 1: endograft limb oversizing ≥15% in one limb, 2: endograft limb oversizing ≥15% in both limbs. A composite variable, consisting of the sum of scoring in variables was analyzed, with a score from 0 to 6. Our study showed that it was the most probable to be in the control group when score in the composite variable was 0-3, it was the most probable to have unilateral limb occlusion when score was 4-5, and finally, it was the most probable to have bilateral limb occlusion when score in the composite variable was equal to 6. CONCLUSIONS: Our study evidenced that the highest probability for bilateral limb occlusion occurred when implantation of a more than 15% oversized endograft in iliac arteries with iliac artery angulation ≥60° and iliac perimeter calcification ≥50% was present in both iliac arteries. It is therefore clear that limb occlusion requires the synergistic effect and interaction of bilateral multiple thrombogenic components in the iliac artery before it is manifested.

Safety and efficacy of polyurethane vascular grafts for early hemodialysis access.

BACKGROUND: Arteriovenous grafts made of polyurethane (PU) have the advantage of early cannulation obviating the placement of a central vein catheter in patients with an acute need for long-term hemodialysis. The aim of the present study was to evaluate the safety, efficacy and complication rate of PU vascular grafts for dialysis access in patients in whom early cannulation was performed. METHODS: Between January 2007 and December 2015, 125 straight brachial-axillary grafts were placed in patients with an acute thrombosis of a previous arteriovenous access. Sixty-four were PU and 61 were polytetrafluoroethylene (PTFE) grafts. Patency and complications rates were compared between the two groups. RESULTS: The median interval from implantation to cannulation was 1 day in the PU group vs 28 days in the PTFE group. Cumulative infection rate at 5 years was 13% and 8% in the PU and the PTFE groups, respectively (P = .6). None of the patients in the PU group developed a pseudoaneurysm necessitating intervention, compared with one patient in the PTFE group. Primary and secondary patency rates did not differ significantly between the two groups. The cumulative median primary patency was 23 months in the PU group vs 26 months in the PTFE group. Median secondary patency was 42 vs 33 months, respectively. Diabetes mellitus was the only factor adversely affecting graft patency in both groups. CONCLUSIONS: PU grafts offer the advantage of early cannulation with infection, pseudoaneurysm formation and patency rates similar to those of the PTFE grafts.

Treatment of Type II Endoleak and Aneurysm Expansion after EVAR.

BACKGROUND: The management of type II endoleak causing sac enlargement continues to be a topic of debate. The purpose of this study was to examine and compare the outcomes between open surgical technique with sacotomy and suturing of the feeding vessels to interventional embolization in patients with aneurysm sac expansion after endovascular aneurysm repair (EVAR). METHODS: Inclusion criteria for intervention in patients with prior EVAR and type II endoleak were asymptomatic expanding aneurysm sac > 5 mm between 2 consecutive follow-up computed tomography angiography scans and symptomatic aneurysm sac expansion. Age, sex, comorbidities, clinical presentation, commercial type of endograft of prior EVAR, aneurysm sac increase, type of treatment, morbidity, mortality, and follow-up were also recorded. RESULTS: A total of 694 consecutive patients were operated with EVAR during the study period. Among them, 29 patients (4.2%) were presented with a type II endoleak that required reintervention. Ten patients (34.5%) were treated with embolization. We recorded a 50% technical success in the group of primary translumbar embolization and 67% in the group of intra-arterial embolization. Twenty-two patients were treated with laparotomy and open ligation of the culprit arteries causing the type II endoleak. Among them, 3 patients (13.6%) had been initially treated with unsuccessful embolization. Periprocedural intervention complications for the embolization group (10%, 1/10) included 1 psoas hematoma. On the contrary, complications after primary open ligation were 13.6% (3/22) and included 1 proximal dislocation treated with endograft explantation, 1 distal dislocation, and 1 limb ligation with femoral-femoral bypass which resulted in colonic ischemia and death (4.5%). CONCLUSIONS: Open surgical repair with sacotomy and suturing of the feeding vessels appeared to have better outcome regarding the exclusion of the aneurysm but was associated with a higher incidence of severe complications and one related death. If these results are confirmed in larger series, endovascular approach should be the preferred treatment option.

The Profile of Circulating Matrix Metalloproteinases in Patients Undergoing Lower Limb Endovascular Interventions for Peripheral Arterial Disease.

BACKGROUND: Matrix metalloproteinases (MMPs) play a significant role in the development and progression of atherosclerotic vascular disease. We aimed to document the profile of circulating MMPs in peripheral arterial disease (PAD) patients undergoing lower limb endovascular revascularization. METHODS: A total of 46 patients (37 male; mean age 66 ± 11 years) undergoing elective lower limb percutaneous revascularization (angioplasty/stent) for symptomatic PAD were recruited from 2 vascular centers. Exclusion criteria were: acute limb ischemia, active infection and/or wet gangrene, liver disease, end-stage renal disease, and cancer. Patients having open revascularization or hybrid (open combined with endovascular) procedures were also excluded. Peripheral venous blood samples were taken on admission and 24 hrs after the procedure. Levels of MMP-2, MMP-3, MMP-7, and MMP-9 were measured along with tissue inhibitors of MMPs (TIMPs) 1 and 2. RESULTS: Compared to baseline values, there was a significant elevation in serum MMP-3 (P = 0.014) and MMP-7 (P = 0.008) levels, whereas serum MMP-9 showed a nonsignificant trend to increase (P = 0.169). On the other hand, no significant alterations were found 24 hrs after angioplasty/stenting with regard to the MMP-2 level and TIMP-1 and 2 levels. CONCLUSIONS: This study documented the periprocedural profile of circulating MMPs in patients undergoing angioplasty/stenting for PAD. The implications of increased MMP-3 and MMP-7 activity after peripheral endovascular interventions and their potential clinical relevance require further investigation.

Inflammatory response and renal function following endovascular repair of the descending thoracic aorta.

PURPOSE: To evaluate inflammatory response and renal function after thoracic endovascular aortic repair (TEVAR) of lesions in the descending thoracic aorta. METHODS: Thirty-two consecutive patients treated with TEVAR from January 2010 to August 2013 were enrolled in this prospective study. Two were excluded owing to dissecting thoracic aortic aneurysm (TAA) extending into the renal arteries with renal failure in one and a saccular TAA in which a multilayer flow-modulating stent was implanted in the other. This left 30 patients (28 men; mean age 68.8±5.9 years) with 28 TAAs, an aortic dissection, and an aortic ulcer for the analysis. Temperature and serum levels of white blood cells (WBCs), C-reactive protein (CRP), interleukin-10 (IL-10), IL-6, IL-8, tumor necrosis factor-alpha (TNF-α), creatinine, urea, and cystatin C were measured preoperatively and at 24 and 48 hours postoperatively. RESULTS: Statistically significant increases in temperature and serum levels of WBCs, CRP, IL-10, and IL-6 were observed 24 and 48 hours postoperatively compared to baseline (all p<0.05). The number of endografts and the coverage of the celiac or subclavian artery did not affect the magnitude of the inflammatory response. No significant differences were observed concerning serum levels of IL-8, TNF-α, creatinine, or cystatin C from baseline to 24 or 48 hours postoperatively. CONCLUSION: Endograft implantation in the thoracic aorta may propagate an inflammatory response during the early postoperative period. No clinical adverse events related to the increased inflammatory response were observed. Renal function does not seem to be deteriorated after TEVAR in the descending thoracic aorta.

Comparison of treatment strategies for thoracic endograft infection.

OBJECTIVE: Endograft infection after thoracic endovascular aortic repair (TEVAR) is associated with a substantial mortality rate that exceeds 70% in the largest published series. The aim of this study was to review all published reports on infection after TEVAR treated with either preservation of the endograft or surgical excision of the stent graft with the intention of providing a comparison of the safety, efficacy, and durability of the two different treatment strategies. METHODS: An extensive electronic health database search was undertaken to identify all articles that were published up to December 2013 reporting on endograft infection after TEVAR. Overall, 55 patients treated with endograft preservation (group A) and 41 patients treated with endograft explantation (group B) were included in this review. RESULTS: The most frequently isolated microorganisms were Streptococcus species (29.4%) and Staphylococcus species (29.4%). The mortality for both groups was 66.6%. The in-hospital mortality rate in group A was 42% and reached 81.8% in a mean follow-up period of 8.6 months. The in-hospital mortality rate in group B was 36.6%. Four (9.7%) further deaths due to reinfection or fistula recurrence were recorded in a mean follow-up period of 15.3 months, leading to an overall mortality of 46.3%. The meta-analysis showed a trend of better outcome with endograft explantation compared with endograft preservation (odds ratio [OR], 0.52; 95% confidence interval [CI], 0.18-1.48). In group A, a trend of better outcome was revealed when drainage and repair of the fistula were applied (OR, 2.22; 95% CI, 0.55-8.90). A trend of worse outcomes was detected in fistula patients compared with nonfistula patients (OR, 1.26; 95% CI, 0.43-3.74). CONCLUSIONS: Endograft preservation seems not a durable option. It can be offered to patients who refuse surgery or as a palliative option or bridging procedure for severely ill patients. Compared with antibiotic therapy alone, antibiotic therapy followed by drainage and repair of the fistula may control the sepsis, providing, however, mainly a temporary benefit. The presence of fistula is a predictor of dismal outcome. Endograft explantation remains the "gold standard" of treatment. The mortality rate of surgical conversion is much higher in the presence of fistula.

Outcome after preservation of infected abdominal aortic endografts.

PURPOSE: To review the published outcomes of aortic endograft infection treated with preservation of the stent-graft. METHODS: An extensive electronic health database search was undertaken to identify all articles published up to May 2013 that reported endograft infection after endovascular aneurysm repair (EVAR) in which treatment included preservation of the stent-graft. The search found 17 articles with 29 patients (27 men; mean age 73.1±7.6 years) fulfilling the inclusion criteria. RESULTS: In 2 (7%) cases, the endograft infection was diagnosed within 30 days of the initial procedure; 4 (14%) were identified within 3 months and the remaining 23 (79%) within 12 months. Staphylococcus species, Streptococcus species, and Escherichia coli were the most common isolated microorganisms. Seven (24%) had a secondary aortoenteric fistula after EVAR. Twelve (41%) patients received only antibiotic therapy, while the remaining had an additional procedure (drainage, surgical debridement, sac irrigation, and/or omentoplasty). The in-hospital mortality was 21% (n=6). During a mean follow-up of 11.4±3.1 months, 7 more patients died (overall mortality 45%). None of the 7 patients with fistula survived. Half (50%) of the 12 patients who received only antibiotic therapy died, while 7 (41%) of the 17 patients who underwent an additional procedure died during follow-up. CONCLUSION: Among patients treated for endograft infection without explantation, those with aortoenteric fistula had the worst outcome. There is evidence for lower mortality in patients who underwent an additional procedure, such as drainage, surgical debridement, and sac irrigation. Larger studies are needed to examine the efficacy of this approach compared to surgical conversion with endograft excision and in situ reconstruction or extra-anatomical bypass.

Endograft infection and treatment with preservation of the endograft: early results in 3 cases.

We present 3 cases of stent graft infection in patients who were treated with preservation of the endograft. In the first patient, the contamination of the endograft was the consequence of a bleeding aortoenteric fistula, whereas in the second patient, the endograft was implanted into a ruptured contaminated aortic aneurysm because of the patient's hemodynamic instability. In the third patient, the presence of a consistent type Ia endoleak after a chimney graft procedure followed by secondary interventions led to an infection of the stent graft. In each case, a laparotomy was performed with debridement, followed by appropriate antibiotic therapy. The first patient suffered a fatal pulmonary embolism. The other 2 patients are alive 4 and 24 months after the diagnosis of endograft infection. In unstable patients or those with severe comorbidities who cannot tolerate endograft excision and aortic reconstruction, surgical debridement followed by appropriate antibiotic therapy can be a temporary or bridging solution.

Novel Biomarkers and Imaging Indices for the "Vulnerable Patient" with Carotid Stenosis: A Single-Center Study.

BACKGROUND: We investigated the relationship of matrix metalloproteinases (MMPs), cardio-ankle vascular index (CAVI), and Gray-Scale Median (GSM) score with the severity and vulnerability of carotid atherosclerosis and major adverse cardiovascular events (MACE) during follow-up of carotid artery revascularization. METHODS: We enrolled 262 patients undergoing carotid revascularization therapy (GRT), 109 asymptomatic patients with low-grade carotid stenosis (40-70%) receiving conservative treatment (GCT), and 92 age- and sex-matched control subjects without carotid atherosclerosis (GCO). All participants underwent carotid ultrasound and we assessed at baseline clinical parameters, metabolic profile, CAVI, GSM, and circulating levels of hsCRP, MMP-3,-7,-9, and TIMP-1. RESULTS: Both GRT and GCT presented with elevated CAVI, MMPs, and TIMP-1 levels compared to GCO (p < 0.001). The escalation highly correlated to the presence of symptoms or paralleled the degree of carotid stenosis (p < 0.001). During follow-up (mean duration: 55 months), 51 GRT patients experienced MACE unrelated to the revascularization procedure. Within GRT, diabetes (HR: 2.07; CI: 1.55-2.78, p < 0.001), smoking (HR: 1.67; CI: 1.35-1.95, p < 0.001), high CAVI (HR: 1.22; CI: 1.09-1.43, p = 0.023) and MMP-9 (HR: 1.44; CI: 1.29-2.15, p = 0.005), and low GSM (HR: 1.40; CI: 1.16-2.12, p = 0.002) independently predicted MACE occurrences, despite the optimum medical therapy. CONCLUSIONS: Novel imaging and biochemical biomarkers were positively associated with atherosclerosis severity, while CAVI, MMP-9, and low GSM showed a positive, independent relationship with MACE after carotid revascularization, describing "vulnerable patients".

The Association of Arterial Stiffness With Significant Carotid Atherosclerosis and Carotid Plaque Vulnerability.

Arterial stiffness and its valid index, the cardio-ankle vascular index (CAVI), have emerged as predictors of adverse cardiovascular outcomes. We investigated the relationship of the CAVI with significant carotid stenosis (> 50%) and the related cerebrovascular symptoms or carotid plaque echogenicity, assessed by ultrasound gray-scale median (GSM) score, at baseline and after carotid artery stenting (CAS). We prospectively enrolled 113 patients with carotid stenosis (70-99% for asymptomatic and > 50% for symptomatic participants) eligible for CAS. Age- and sex-matched individuals (n = 38) served as controls (CON). Clinical data, CAVI, and biochemical profile were obtained at baseline. Clinical assessment and CAVI measurement were performed 6 months after CAS. Compared with the CON group, the CAS group had a higher incidence of co-morbidities (diabetes, hypertension, and hyperlipidemia), higher CAVI values (9.94 ± 2.14 vs 7.85 ± .97 m/sec, P < .001), but a better lipid profile due to increased prescription of statins. The symptomatic CAS subgroup showed higher CAVI (P < .001), high-sensitivity C-reactive protein (P = .048), and osteoprotegerin (P = .002) levels than the asymptomatic one. In multivariate analysis, CAVI at baseline was independently associated with the presence of significant carotid atherosclerosis (ß = .695, P < .001), cerebrovascular events (ß = .474, P < .001), and GSM score (ß = -.275, P = .042). Raised CAVI values were independently associated with significant carotid stenosis and plaque vulnerability.

The value of near-infrared spectroscopy for the assessment of calf muscle function in venous patients.

OBJECTIVE: Near-infrared spectroscopy (NIRS) is a noninvasive technique with the potential to determine the degree of tissue oxygenation. The aim of the current study was to investigate the use of NIRS as a reliable method of detecting calf muscle pump dysfunction in groups of patients with venous disease. METHODS: Patients with superficial venous insufficiency (SVI) or history of deep venous thrombosis (DVT) were classified according to the comprehensive classification system for chronic venous disorders (clinical class, etiology, anatomy, and pathophysiology) and compared with controls (GROUP variable). A 10-stage evaluation of ambulatory venous function was performed, and corresponding values of calf regional oxygen saturation (crSaO2, %) at each phase were recorded (TIME variable). Thereafter, the percentage changes of crSaO2 values (Δ scores, %) between a given phase and the reference phase were estimated. Differences among groups and phases were evaluated using analysis of variance. Subgroup analysis between C0-C2 and C3-C6 patients was performed. The receiver operating characteristic curve analysis was used to detect the best predictive capability for SVI and DVT. RESULTS: A total of 30 patients with SVI, 31 patients with DVT, and 34 controls were included in the study. A statistically significant effect of TIME (F = 382.4; P < .001) and TIME × GROUP interaction (F = 6.3; P < .001) was recorded. Concerning prediction, we found a statistically significant area under the curve (AUC) for SVI (AUC = 0.72; 95% confidence interval, 0.58-0.83; P = .003) and for DVT (AUC = 0.83; 95% confidence interval, 0.71-0.92; P < .0001) patients. CONCLUSIONS: The measurement of crSaO2 using NIRS detected alterations in calf muscle pump oxygenation during exercise and differences in tissue oxygenation among SVI patients, DVT patients, and controls. NIRS may represent a reliable noninvasive tool for the study of calf muscle dysfunction in venous disease and a useful vehicle for generating testable hypotheses in the laboratory setting.

Vascular Injury in Orthopedic Trauma.

Vascular injury in orthopedic trauma is challenging. The risk to life and limb can be high, and clinical signs initially can be subtle. Recognition and management should be a critical skill for every orthopedic surgeon. There are 5 types of vascular injury: intimal injury (flaps, disruptions, or subintimal/intramural hematomas), complete wall defects with pseudoaneurysms or hemorrhage, complete transections with hemorrhage or occlusion, arteriovenous fistulas, and spasm. Intimal defects and subintimal hematomas with possible secondary occlusion are most commonly associated with blunt trauma, whereas wall defects, complete transections, and arteriovenous fistulas usually occur with penetrating trauma. Spasm can occur after either blunt or penetrating trauma to an extremity and is more common in young patients. Clinical presentation of vascular injury may not be straightforward. Physical examination can be misleading or initially unimpressive; a normal pulse examination may be present in 5% to 15% of patients with vascular injury. Detection and treatment of vascular injuries should take place within the context of the overall resuscitation of the patient according to the established principles of the Advanced Trauma Life Support (ATLS) protocols. Advances in the field, made mostly during times of war, have made limb salvage the rule rather than the exception. Teamwork, familiarity with the often subtle signs of vascular injuries, a high index of suspicion, effective communication, appropriate use of imaging modalities, sound knowledge of relevant technique, and sequence of surgical repairs are among the essential factors that will lead to a successful outcome. This article provides a comprehensive literature review on a subject that generates significant controversy and confusion among clinicians involved in the care of trauma patients. [Orthopedics. 2016; 39(4):249-259.].

Arterial Stiffness Alterations and Inflammatory Response Following Endovascular Aortic Repair: Based on a Presentation at the 2013 VEITH Symposium, November 19-23, 2013 (New York, NY, USA).

Endovascular abdominal aortic aneurysm repair (EVAR) and thoracic aortic aneurysm repair (TEVAR) have been widely incorporated into clinical practice. However, changes in arterial stiffness and post-implantation syndrome after aortic endografting remain important issues under investigation. The aneurysm sac wall motion after successful EVAR and TEVAR reflects complex interactions between all the components of the excluded aneurysm, including true compliance of the aneurysm wall itself, intra-aneurysm sac pressure, remodeling of the thrombus, and mechanical characteristics of the endograft. Experimental and clinical studies have shown that aortic endografting results in increased arterial stiffness in animal models. It can be assumed that the alterations of aortic mechanical properties can have a direct impact on heart output. The long-term impact of these mechanical changes on cardiovascular outcomes and the potential effects of different endografts on hemodynamics are important issues under investigation. Post-implantation syndrome (PIS) is a systemic inflammatory response frequently observed after endovascular treatment of aortic pathologies. The main features of PIS include fever, leukocytosis, elevated C-reactive protein levels, and coagulation disturbances. Endograft design appears to influence this inflammatory response following aortic endografting; woven polyester endografts have been shown to be associated with greater inflammatory response compared to PTFE stent grafts. The purpose of this paper is to review the literature to elucidate arterial stiffness alterations and inflammatory response after EVAR and TEVAR and the impact of endograft design on aortic stiffness and the post-inflammatory response.