PubMed Health⌕ Search

Biomedical subjects

Sean P Lyden

Publications and source records attributed to Sean P Lyden.

At least 19 recordsLinked to original sources
PubMed2025

Circulating Trimethylamine N-Oxide and Growth Rate of Abdominal Aortic Aneurysms and Surgical Risk.

IMPORTANCE: Plasma levels of the gut microbiota-dependent metabolite trimethylamine N-oxide (TMAO) are associated with prevalent abdominal aortic aneurysms (AAA) in humans and fostering of AAA progression in animal models; therapeutic targeting of TMAO production blocks AAA progression and rupture in multiple mouse models. A blood biomarker that identifies individuals at risk for incident AAA development, accelerated AAA expansion, or recommendation for surgical AAA repair could be an asset for risk stratification. OBJECTIVE: To determine whether TMAO is associated with risk for AAA development, rapid AAA expansion, and risk for recommended surgical intervention. DESIGN, SETTING, AND PARTICIPANTS: This was a prospective cohort study using 2 independent clinical cohorts undergoing aorta imaging surveillance: a European cohort and a US cohort. Included in this study were patients undergoing serial imaging surveillance of the aorta and long-term outcome monitoring. Patients were recruited from single-center studies in Uppsala, Sweden, and Cleveland, Ohio. Study data were analyzed from October 2023 to May 2025. EXPOSURES: Plasma TMAO concentrations measured by stable isotope dilution liquid chromatography with tandem mass spectrometry. MAIN OUTCOMES AND MEASURES: The association of TMAO levels with AAA risk, fast-growing AAA (≥4.0 mm per year), and recommended surgical intervention (≥4.0 mm per year or ≥5.5 cm diameter). RESULTS: The European cohort included 237 individuals (median [IQR] age, 65 [65-73] years; 211 male [89.0%]), and the US cohort included 658 individuals (median [IQR] age, 63 [57-70] years; 523 male [79.5%]). In the European cohort, elevated circulating TMAO was significantly associated with AAA risk independent of traditional risk factors and kidney function. Moreover, elevated TMAO predicted both greater risk for fast-growing AAA (adjusted odds ratio [aOR], 2.75; 95% CI, 1.20-6.79) and recommended surgical intervention (aOR, 2.67; 95% CI, 1.24-6.09). Similar patterns were observed in the US cohort and the combined European and US cohort, with heightened circulating TMAO corresponding with significantly increased adjusted risk for fast-growing AAA (US cohort: aOR, 2.71; 95% CI, 1.53-4.80; combined cohort: aOR, 2.30; 95% CI, 1.47-3.62) and recommended surgical intervention (US cohort: aOR, 2.73; 95% CI, 1.56-4.80; combined cohort: aOR, 2.41; 95% CI, 1.55-3.74). Addition of TMAO to base models containing traditional cardiovascular risk factors resulted in significant improvement in both risk estimation for fast-growing AAA and predicting recommended surgical intervention. CONCLUSION AND RELEVANCE: Results of this cohort study suggest that elevated circulating TMAO levels were associated with increased risk of AAA and identified patients at heightened risk for fast-growing AAA and recommended surgical intervention. TMAO may help identify individuals who may benefit from more frequent surveillance imaging and early surgical intervention to prevent aortic dissection or rupture.

Humans↗
PubMed2006

Nonseminomatous germ cell tumor after chemotherapy with residual mass invading the spine.

Bony metastasis is a rare feature of metastatic nonseminomatous germ cell tumor. A 25 year-old man presented with back pain radiating down both legs, and a subsequent work-up demonstrated a right-sided testicular mass with bilateral retroperitoneal lymphadenopathy and tumor involvement of the L2 vertebra. Radical inguinal orchiectomy confirmed nonseminomatous germ cell tumor, and the patient underwent chemotherapy with a residual mass and vertebral involvement by MRI. Combined vertebral resection with spinal reconstruction and retroperitoneal lymph node dissection demonstrated residual fibrosis. While bony metastasis of nonseminomatous germ cell tumors is rare, resection with spinal reconstruction can be accomplished with acceptable morbidity.

Adult↗
PubMed2006

Endovascular management of iliac artery occlusions: extending treatment to TransAtlantic Inter-Society Consensus class C and D patients.

OBJECTIVE: The preferential use of endovascular techniques to treat complex aortoiliac disease has increased in recent years. The purpose of this study was to review the outcomes and durability of recanalization, percutaneous transluminal angioplasty, and stenting for iliac occlusions based on the patient's TransAtlantic Inter-Society Consensus (TASC) stratification. METHODS: Between 1998 and 2004, more than 628 patients with a clinical diagnosis of aortoiliac atherosclerotic disease underwent arteriography. The endovascular treatment of 89 consecutive patients (mean age, 66 years; 58% male) with symptomatic iliac occlusions (TASC-B, -C, and -D) was the basis for this study. Original angiographic imaging was evaluated for lesion grade and runoff. Electronic and hard copy medical records were reviewed for demographic data, clinical variables, and noninvasive vascular laboratory testing. Kaplan-Meier estimators were used to determine patency rates according to Society for Vascular Surgery criteria. Univariate and multivariate analyses were performed. P values of <.05 were considered significant. RESULTS: Recanalization and percutaneous transluminal angioplasty/stenting (total, 178 stents) of occluded iliac arteries was technically successful in 84 (91%) of 92 procedures. Patients in the TASC-C and -D groups often required multiple access sites (50%) and femoral artery endarterectomy/patch angioplasty for diffuse disease (24%). The mean ankle-brachial index increased from 0.45 to 0.83. Distal embolization led to major amputation and eventual death in one patient. Two other deaths occurred in the perioperative period secondary to cardiorespiratory causes. Three-year primary patency, secondary patency, and limb salvage rates were 76%, 90%, and 97%, respectively, and progression of infrainguinal disease led to late limb loss in two patients. Diabetes as a risk factor was significantly associated with decreased primary patency (57% vs 83%; P = .049). Critical ischemia at presentation was associated with decreased patency rates as well (P = .002), but TASC classification did not significantly alter patency rates. CONCLUSIONS: Complex long-segment and bilateral iliac occlusions can be safely treated via endovascular means with high rates of symptom resolution. Initial technical success, low morbidity, and mid-term durability are comparable to results with open reconstruction. A liberal posture to open femoral artery reconstruction extends the ability to treat diffuse TASC-C and -D lesions via endovascular means.

Arterial Occlusive Diseases↗
PubMed2006

Beyond the aortic bifurcation: branched endovascular grafts for thoracoabdominal and aortoiliac aneurysms.

OBJECTIVES: To evaluate the use of novel technology to treat complex aortic aneurysms involving branches that provide critical end-organ blood supply. METHODS: A prospective study was conducted in patients with thoracoabdominal, suprarenal, or common iliac aneurysms (TAA, SRA, or CIA) at high risk for open surgical repair. An endovascular graft using the Zenith platform was customized to fit patient anatomy (TAA or SRA) and combined with Jomed balloon-expandable stent-grafts. Prefabricated hypogastric branches were used with a Zenith abdominal aortic aneurysm (AAA) or Fluency self-expanding fenestrated device in conjunction with a self-expanding stent-graft. Analyses were conducted in accordance with the endovascular aneurysm reporting standards document. Follow-up studies occurred at discharge, 1, 6, and 12 months, and included computed tomography and duplex ultrasound scans, and flat plate radiography. RESULTS: Fifty patients were treated (9 TAA, 20 SRA, 21 CIA). The mean aneurysm size was 7.6 cm (TAA), 7.2 cm (SRA), and 6.1 cm AAA size associated with a mean CIA size of 3.8 cm. Bilateral CIA aneurysms were present in 86% (18/21) of patients with CIA aneurysms. Perioperative mortality was 2% (1/50) and resulted from a myocardial infarction after a planned conduit and iliac endarterectomy required for device access. Five late deaths occurred (2 TAA, 2 SRA, 1 CIA), three of which (2 TAA, 1 SRA) were aneurysm related. Failure to access internal iliac arteries occurred in three cases, and two late hypogastric branch thromboses occurred. No visceral branches were lost acutely or occluded during follow-up. Sac shrinkage (>5 mm) was noted in 65% of patients at 6 months and in all patients (10/10) by 12 months. There were no ruptures or conversions, but nine patients required secondary interventions. CONCLUSIONS: Branch vessel technology has made it technically feasible to preserve critical end-organ perfusion in the setting of CIA, SRA, and TAA aneurysms. The relatively low acute mortality rate and lack of short-term branch vessel loss are encouraging and merit further investigation. These advances have the potential to markedly diminish the complications associated with conventional management of complex aneurysms.

Angioplasty↗
PubMed2006

An evaluation of centerline of flow measurement techniques to assess migration after thoracic endovascular aneurysm repair.

OBJECTIVE: To validate a means by which migration of thoracic stent grafts can be reliably detected and quantified. METHODS: Patients treated for thoracic aneurysms (without dissections) with either the Cook Zenith TX1/TX2 or the Gore TAG device were retrospectively reviewed. Patients with digital imaging data at a baseline study (discharge or 1-month computed tomographic scan) and a minimum of 6 months' follow-up were evaluated on a three-dimensional workstation. Centerline of flow (CLF) calculations were used to determine length measurements to establish distances from native vascular landmarks (left common carotid artery, left common carotid artery, and celiac artery) to the proximal and distal aspects of the fixation systems of stent grafts. Patients with evidence of fixation system migration (>10 mm of movement) or increasing thoracic aortic lengths (left common carotid artery to celiac artery distance) were subjected to more detailed reviews. RESULTS: Of 194 patients evaluated (133 Zenith and 61 TAG), 46 were treated for dissections and excluded. Fifty-seven patients did not have a digital baseline study and available DICOM data for follow-up imaging at 6 months or later or had died before such follow-up imaging. The remaining 91 patients underwent assessment for device migration. Analyses were conducted on 19 patients at 6 months, on 42 at 12 months, on 12 at 24 months, on 13 at 36 months, and on 5 at 48 months. CLF analysis noted more than 10 mm of caudal movement of the proximal device in 10 patients and cranial movement of the distal device in 3 patients. When this subset was further scrutinized with regard to morphologic changes remote from the prosthesis and in the context of the overall aortic repair (such as elephant trunk grafts), only four patients had movement of the proximal or distal fixation system with respect to the initially deployed location. Two-dimensional axial image analysis identified migration in only one of the four patients with CLF-detected fixation system movement. CONCLUSIONS: The importance of early migration detection cannot be overstated given the potential to avert consequences as evidenced by analyses of counterpart abdominal aortic aneurysm devices. In vivo thoracic device analysis is more complex than that for devices used for infrarenal aneurysms. Distance calculations based on CLF measurements may overestimate the frequency of true migration, yet they serve as a reasonable initial screening tool. The resultant subset of patients then must undergo a more detailed evaluation of device position in the context of the aortic morphology to differentiate true migration from devices that maintain stable fixation system positions.

Algorithms↗
PubMed2006

Contemporary endovascular treatment for disease of the superficial femoral and popliteal arteries: an integrated device-based strategy.

Endovascular therapy for disease of the superficial femoral artery (SFA) and the popliteal artery remains controversial. Percutaneous treatment of this arterial segment presents a particular technical challenge, as the extent of disease varies from short, focal, and stenotic to long, diffuse, and occluded lesions. Over the last 2 decades, multiple therapies have been evaluated, including simple balloon angioplasty, directional atherectomy, stenting (both balloon-expandable and self-expanding), and more recently, intra-arterial radiation, laser, and cryotherapy. Regardless of which modality is used, however, endovascular therapy as a revascularization strategy has the potential to improve symptoms and quality of life and, in selected patients, to avoid limb amputation. While percutaneous endovascular treatment has been historically associated with high procedural success and favorable short and intermediate-term patency rates, long-term clinical results have proven disappointing. Conventional balloon angioplasty is limited by elastic recoil, dissection, and restenosis. Balloon-expandable stents (particularly in the distal SFA) are associated with late stent deformation and mechanical compression, with resultant late clinical failure. Newer self-expanding stents have shown improved initial results but have been limited by late mechanical fatigue and associated restenosis. With the development of several newer endovascular techniques in recent years, the possibilities for treating this condition have increased dramatically. Currently, no long-term comparative data exist regarding the role of these alternative technologies. This article summarizes and compares important data about new endovascular options for intervention therapy in SFA and popliteal disease. In addition, based on this analysis, we propose a contemporary treatment strategy, integrating older and newer technologies into a real-world algorithm.

Algorithms↗
PubMed2006

Combined staged procedures for the treatment of thoracoabdominal aneurysms.

PURPOSE: To examine the efficacy of a staged approach for the treatment of thoracoabdominal aneurysms, with open visceral revascularization followed by aortic endografting, in selected patients not considered candidates for conventional surgical repair. METHODS: A retrospective review was conducted of 13 consecutive patients (8 women; mean age 64 years, range 33-77) who underwent visceral bypass followed by endovascular thoracoabdominal stent-graft implantation since 1999. Three patients presented with symptomatic aneurysms and 2 with rupture. Two patients had connective tissue disorders. All patients were deemed unfit for conventional thoracoabdominal repair due to comorbid conditions. The procedures were tailored to the pathology and specific patient anatomical situation: 5 aortic dissections with aneurysmal degeneration and 8 aneurysms (5 Crawford type II, 2 type III, and 1 type IV). RESULTS: The patients underwent retrograde visceral bypass (11 iliovisceral and 2 infrarenal aortic to visceral artery) followed by endovascular aortic relining with Zenith TX2 devices (n=7), homemade endografts (n=5), or a Talent thoracic endograft (n=1). Six patients required either a proximal or distal direct aortic repair (2 infrarenal reconstructions, 3 arch elephant trunk grafts, and 1 ascending aortic repair), while 3 patients also underwent left carotid-subclavian bypass grafting. Two patients developed paraplegia (1 following a ruptured aneurysm), and 2 patients had transient paraparetic events. Two patients had acute renal failure requiring short-term dialysis. Three patients died within 30 days; 2 late aneurysm-related deaths were noted. Three patients developed endoleaks during follow-up. Mean lengths of stay were 13 days (7-30) for the visceral bypass and 12 (3-25) for the endovascular stent-graft. In addition, remaining procedures in 8 patients required a mean of 7 days (0-14) in hospital. CONCLUSION: Staged endovascular and open procedures are feasible for thoracoabdominal aneurysms in patients at prohibitive risk for open thoracoabdominal reconstruction. However, this approach still carries a significant risk of perioperative mortality and morbidity. The potential for less invasive alternatives should be investigated.

Adult↗
PubMed2005

Hybrid approaches to thoracic aortic aneurysms: the role of endovascular elephant trunk completion.

BACKGROUND: Thoracic aortic aneurysm affecting the arch and proximal descending thoracic aorta requires 2-stage repairs that include proximal elephant trunk graft placement and completion of thoracic or thoracoabdominal repair. The application of endovascular grafting to complete the proximal procedure avoids a thoracotomy and may improve the morbidity and mortality of the patient population at risk. METHODS AND RESULTS: A retrospective review of 399 thoracic endovascular grafts at our institution between 2000 and 2004 identified 22 patients who required elephant trunk and endovascular completion. Three patients underwent mesenteric bypass in addition to their proximal repairs. Mean follow-up was 10 months (range 1 to 42 months); there were no ruptures, and all patients returned for follow-up. Technical success was achieved in all patients. The 1-, 12-, and 24-month mortality rates (by Kaplan-Meier analysis) were 4.5%, 15.8%, and 15.8%, respectively. Caudal migration of the endograft occurred in 1 patient, and all but 2 aneurysms decreased or remained stable in size. The 2 patients with growth included a type III endoleak (which resolved after treatment) and pressurization through an expanded PTFE stentgraft. Three cases of transient paraparesis occurred (all in patients requiring mesenteric bypass or abdominal aortic aneurysm repair), and there were no paraplegias or strokes. CONCLUSIONS: Endovascular completion of elephant trunks is feasible and can be accomplished with minimal mortality. Meticulous imaging follow-up is required to detect persistent aneurysm pressurization and to verify the integrity of the repair. Improvements in implant design and delivery systems will further simplify the second-stage portion of these complex aneurysm repairs.

Aorta, Thoracic↗
PubMed2005

Fenestrated endovascular grafting: The renal side of the story.

BACKGROUND: Fenestrated endovascular aneurysm repair uses the visceral aortic segment, in the setting of a suboptimal proximal neck, for sealing and fixation. This technique requires the placement of visceral stents and might be hampered by the deleterious effects of such interventions. This study was performed to define outcomes related to renal events. MATERIALS AND METHODS: Consecutive clinical records and radiographic studies of patients treated primarily with an endovascular approach with a fenestrated endograft were reviewed. The population was divided into groups with and without baseline renal dysfunction based on the National Kidney Foundation definition of chronic kidney disease. Morphologic measurements and the detection of postoperative renal events such as renal artery stenosis or occlusion, need for dialysis, deterioration of renal function by using estimated glomerular filtration rate (GFR), and secondary interventions related to the renal arteries were assessed. Preoperative and postprocedural factors predictive for the development of renal dysfunction were assessed by using a Fisher exact test, t test, and logistic regression. RESULTS: A total of 72 patients were treated between 2001 and 2004 with a mean age, aneurysm size, and follow-up of 75 years, 6.2 cm, and 6 months (range, 1 to 24 months), respectively. No ruptures and five deaths (two procedure-related) were observed. There were 23 patients with baseline renal insufficiency and 49 patients without insufficiency. Twenty-four patients had deterioration in GFR >30% during the follow-up period, and 17 patients experienced 19 renal-related events (more common in patients with baseline insufficiency, 39% vs 16.3%; P = .04; relative risk, 2.4). Four patients required dialysis (two permanent), and all had preoperative renal dysfunction ( P = .002); similarly, death was also more common in this group (17.4% vs 2%; P = .02; relative risk, 8.52). Renal events in most patients occurred within the first postoperative month (59%). However, mean GFR stabilized after 6 months. CONCLUSION: Aneurysm repair with fenestrated endovascular grafts is associated with a significant risk for adverse renal events (16% in those without renal dysfunction, although none developed a creatinine >2 mg/dL, and 39% for patients with preoperative renal dysfunction). These patients must be meticulously followed, particularly within the first month after such a procedure. When renal artery restenosis is suspected or diagnosed, aggressive approach might be warranted to limit the extent of late renal dysfunction.

Aged↗
PubMed2005

Endovascular repair of thoracic aortic lesions with the Zenith TX1 and TX2 thoracic grafts: intermediate-term results.

PURPOSE: This prospective study was designed to assess the technical success and outcome after patients with thoracic aortic pathology at high risk for conventional therapy were treated with the Zenith TX1 and TX2 endovascular graft. METHODS: Between 2001 and 2004, patients at high risk for conventional surgical therapy presenting with chronic aortic dissections, thoracic aneurysms, or aortobronchial or aortoesophageal fistulas were treated with a single- or multiple-piece endovascular grafts. Surgical modification of proximal or distal fixation sites was performed when necessary to establish adequate regions for device landing zones. Follow-up studies included radiographic evaluation before discharge and at 1, 6, 12, and 24 months. Aortic morphologic characteristics were determined by using three-dimensional imaging studies and centerline of flow measurements. Statistical analyses were performed with Kaplan Meier analysis to assess survival, factors predictive of poor outcome, and morphologic changes, including sac shrinkage. RESULTS: A total of 100 patients (42% women) were treated, including 81 aneurysms, 15 aortic dissections (with aneurysms), 2 patients with fistulous connections (1 aortobronchial and 1 aortoesophageal), 1 subclavian artery aneurysm, and 1 aortic rupture. Mean follow-up and aneurysm size were 14 months and 62 mm, respectively. Most patients (55%) had undergone prior aortic aneurysm repair. Surgical modifications were required to create adequate implantation sites in 29% patients, including 14 elephant trunk/arch reconstructions, 18 carotid-subclavian bypasses, and 4 visceral vessel bypasses. Iliac conduits were required in 19 patients. Overall mortality was 17%, and aneurysm-related mortality was 14% at 1 year. Sac regression (>5 mm maximum diameter decrease) was observed in 52% and 56% at 12 and 24 months. Growth was noted in one patient (1.6%) at 12 months. Endoleaks were detected in eight patients (8.5%) at 30 days and three patients (6%) at 12 months. Secondary interventions were required in 15 patients. Migration (>10 mm) of the proximal or distal stent was noted in three patients (6%) (two proximal and one distal), none of which required treatment or resulted in an adverse event. CONCLUSIONS: Acceptable intermediate-term outcomes have been achieved in the treatment of high-risk patients in the setting of both favorable and challenging anatomic situations with these devices. The complexity of the patient population, in contrast to endovascular infrarenal repair, attests to the differences in the pathophysiology aortic disease in the anatomic beds.

Adult↗
PubMed2005

Combined open and endovascular treatment of a right subclavian artery aneurysm: a case report.

A 69-year-old man with previous ascending aortic repair combined with valve replacement for an ascending aortic aneurysm presented with a type 2 thoracoabdominal aneurysm and a 4.4-cm aneurysm of the right subclavian artery. Because of the anatomic location of the aneurysm and his previous operation, an innominate to carotid artery stent graft and a carotid-subclavian bypass and vertebral artery bypass were performed. Postoperative computed tomographic angiography confirmed good flow in the right carotid and vertebral artery, and the patient recovered without complication.

Aged↗
PubMed2004

Variable sac behavior after endovascular repair of abdominal aortic aneurysm: analysis of core laboratory data.

OBJECTIVES: The behavior of the aneurysm sac after endovascular grafting has been the subject of significant speculation. The importance of sac behavior is manifested by the correlation between aneurysm size or size change and risk for rupture, and potentially further extrapolated to define the need for secondary intervention. This study was undertaken to define graft-specific differences and the effect of endoleak on sac remodeling. METHODS: Core laboratory data were obtained for three US Phase II clinical trials. Patients were included if they met anatomic inclusion criteria and underwent placement of the latest version of a bifurcated endovascular prosthesis. Unsupported Dacron (Ancure), supported Dacron (Zenith), and expanded polytetrafluoroethylene (Excluder) grafts were evaluated. Digitized images were electronically assessed for aneurysm size (area, maximum, minimum diameter) with National Institutes of Health Image software. Two blinded reviewers analyzed each radiographic study to ensure accurate image selection and establish the presence or absence of endoleak. A third reviewer adjudicated discrepancies. chi(2) analysis and mixed nonlinear modeling were used to analyze the results. RESULTS: Of 1506 patients evaluated, 723 (227 Ancure, 343 Excluder, 153 Zenith) met inclusion criteria for the study. Mean follow-up was 23.2 months (Ancure, 31.3 months; Excluder, 19.6 months; Zenith, 19.3 months). The incidence of any endoleak was 39.1% (Ancure, 58.1%; Excluder, 34.7%; Zenith, 20.9%; P <.001). Type of prosthesis, presence or absence of endoleak, and baseline size were determinants of rate of aneurysm shrinkage. Reduction in sac size was greatest with the Zenith graft, followed by the Ancure and Excluder grafts. Presence of endoleak had a moderating effect on rate of sac shrinkage with the Zenith and Ancure grafts; however, sac size increased in the presence of endoleak with the Excluder graft. Finally, baseline size was positively correlated with rate of aneurysm shrinkage. CONCLUSIONS: The behavior of the aneurysm sac depends on the type of prosthesis, presence or absence of endoleak, and baseline size of the sac. Differential sac behavior must be considered when determining the need for secondary interventions, timing follow-up studies, and assessing success or failure of endovascular repair.

Aorta, Abdominal↗
PubMed2004

Endovascular management of juxtarenal aneurysms with fenestrated endovascular grafting.

PURPOSE: To evaluate the technical feasibility and short-term results of juxtarenal aneurysm repair with an endovascular graft that incorporated the visceral aortic segment with graft material. METHODS: Patients were studied prospectively after the implantation of an endovascular device with graft material extending proximal to the renal arteries, variably incorporating the superior mesenteric and celiac arteries. All patients were deemed to be high risk with respect to open surgical repair and had compromised proximal neck anatomy. Proximal neck lengths were <or=10 mm, or <or=15 mm with a challenging morphology (funnel shape or extensive thrombus). Fenestrations within the graft material were customized to accommodate visceral and renal vessels on the basis of computerized tomography (CT), angiography, or intravascular ultrasound data. Selected visceral ostia were protected with balloon-expandable stents after partial endograft deployment. All patients were evaluated with CT and kidney, ureters, and bladder x-ray at discharge and at 1, 6, and 12 months. Visceral duplex scan studies were performed at 1, 6, and 12 months. RESULTS: A total of 22 patients were enrolled in the study. Sixteen patients had short proximal necks (3-10 mm), and six had compromised necks of 10 to 15 mm in length. Endograft design included bifurcated (20) and tube (2) systems. All prostheses were implanted successfully without the acute loss of any visceral arteries. A total of 58 visceral vessels were incorporated (mean, 2.6 per patient) and most commonly included both renal arteries and the superior mesenteric artery. The mean follow-up was 6 months. There were no deaths within 30 days and no aneurysm-related deaths during the follow-up period. Two early (<30 days) and two late secondary interventions were performed, inclusive of two visceral artery stenoses detected with duplex scanning. The 30-day endoleak rate was 4.5%. The aneurysm sac decreased greater than 5 mm in 53 % of patients at 6 months and three of four patients at 12 months. Three patients developed renal insufficiency, only one of which required temporary hemodialysis. CONCLUSIONS: The placement of an endovascular prosthesis with graft material that incorporates the visceral arteries is technically feasible. The occurrence of endoleaks appears to be relatively low. The increased sealing and fixation zones in this patient population should limit the late development of proximal endoleak or migration; however, this situation will require more patients and extended follow-up.

Aged↗
PubMed2004

Initial management and outcome of aortic endograft limb occlusion.

OBJECTIVE: The purpose of this study was to determine the differences in outcome related to initial management of aortic endograft limb occlusion (ELO). METHODS: During a 7-year period, 823 endovascular aneurysm repairs (EVARs) resulted in 25 ELOs in 22 patients. The initial management and outcome of these ELOs were reviewed. Median follow-up after ELO was 24.2 +/- 16.8 months. RESULTS: Initial EVARs included both unsupported unibody (n = 5) and supported modular (n = 17) devices. ELO was significantly more common in the unsupported unibody graft design (P <.024) and with extension of the graft limb to the external iliac artery (P <.001). ELO was managed with an endovascular approach (EVA), including some combination of mechanical thrombectomy (n = 8), angioplasty with or without stenting (n = 8), and thrombolysis (n = 2) in 12 patients and bypass procedures (femoral-femoral bypass, n = 11; axillofemoral bypass, n = 1; and aortofemoral bypass, n = 1) in 13. At 12-month follow-up, freedom from secondary procedures with EVA was 80.2 +/- 17.7% versus 53.2 +/-17.1% with extra-anatomic bypass (EB) (P = NS). Secondary patency was 100% with EVA and 80.6 +/- 14.4% with EB (P = NS). Of the 12 EVAs, there was 1 (8.3%) perioperative mortality with EVA and none with EB. EB failure was directly attributed to donor limb occlusion in 4 of 6 EVAs (67%), and when this occurred it resulted in bilateral lower extremity ischemia. Amputation was required in 2 of 12 (16.7%) EBs versus none of the 12 EVAs (P = NS). EVA never resulted in graft dislodgement or endoleak but did identify an underlying treatable cause in 8 of 12 (67%). CONCLUSION: Both EVA and EB are acceptable management strategies for ELO. The potential risk of graft dislodgement was not observed with an EVA. If EB is employed, assessment of the donor limb and treatment of any underlying lesions is advisable in an attempt to minimize future donor limb occlusion.

Angioplasty↗
PubMed2004

Stent-graft migration: a reappraisal of analysis methods and proposed revised definition.

PURPOSE: To demonstrate the need for a radiographic definition of migration that accurately describes a specific failure mode of an aortic stent-graft. METHODS: The diagnosis of endograft migration, as defined by the Society for Vascular Surgery/American Association for Vascular Surgery (SVS/AAVS) standards, requires a synthesis of clinical and/or radiographic observations. Radiographic studies and clinical reports of 704 consecutive patients treated over a 6-year period with abdominal aortic endografts were retrospectively reviewed. According to the current SVS/AAVS standards, 25 patients were identified as having endograft migration. Follow-up computed tomographic scans and radiographs available for 24 of these patients were scrutinized from discharge to the time of any observed proximal or distal fixation system movement based upon the discharge or 30-day CT scan. Proximal migration was defined with respect to the origin of the superior mesenteric artery (SMA) as movement in a caudal or cranial direction of >/=10 mm or >2 times the reconstructed resolution of the imaging study (whichever measurement was less). Distal migration was similarly defined using the aortic bifurcation and respective hypogastric artery origin as reference points. In an effort to assess the scan-to-scan variation, the distance between the SMA and lowest renal artery, which was expected to remain consistent, was measured. RESULTS: Film analysis with application of the revised migration definition confirmed fixation system failure with respect to the native arterial system in 12 (50%) of the 24 patients. Subjects judged to have endograft migration according to the reporting standards but not to have radiographic evidence of migration based on the modified criteria included 2 proximal endoleaks without evidence of device movement treated with proximal extensions, 1 procedure-related migration, 2 type III endoleaks treated with a second prosthesis implanted within the first, 1 distal endoleak treated with a limb extension, 1 rupture with presumed distal limb migration, and 2 cases of component separation. Three limb extensions were placed in the absence of leak or migration. These 12 patients all had radiographic evidence that the proximal and distal aspects of the originally implanted device did not move with respect to the native arterial vasculature, thus confirming stability of the respective fixation system. CONCLUSIONS: Adherence to this comprehensive definition of device migration, which differs from the published reporting standards, allows differentiation of the specific mechanisms of device failure. Data viewed in this context will aid in the understanding of device strengths and weaknesses, potentially improve patient assessment, and encourage design modifications to address specific aspects relating to fixation failure.

Aorta, Abdominal↗
PubMed2003

Disparate outcome after endovascular treatment of small versus large abdominal aortic aneurysm.

OBJECTIVES: The size of an abdominal aortic aneurysm is the most important parameter for determining whether repair is appropriate. This decision, however, must be considered in the context of long-term outcome of treatment, balancing risk for rupture with mortality from the initial procedure and all subsequent secondary procedures necessary when durability is not ideal. Information on the results of endovascular repair of small versus large aneurysms has not been available. METHODS: Preoperative imaging studies and postoperative outcome were assessed in 700 patients who underwent endovascular repair of abdominal aortic aneurysm over 6 years at a single institution. Patients were divided into two groups: 416 patients (59.4%) with aneurysms smaller than 5.5 cm in diameter and 284 patients (40.6%) with aneurysms 5.5 cm or larger in diameter. Outcome variables were assessed with the Kaplan-Meier method and the log-rank test. RESULTS: Patients with small and large aneurysms were comparable with regard to all baseline parameters assessed, with the single exception of a small increase in age (2.3 years) in patients with large aneurysms (P =.031). While there were no differences in rate of type II endoleaks, mid-term changes in sac diameter, or aneurysm rupture between the two groups, at 24 months patients with large aneurysms had more type I leaks (6.4% +/- 2.3% vs 1.4% +/- 0.6%; P =.011), device migration (13% +/- 4.0% vs 4.4% +/- 1.8%; P =.006), and conversion to open surgical repair (8.2% +/- 3.2% vs 1.4% +/- 1.1%; P =.031). Of greatest importance, at 24 months patient survival was diminished (71% +/- 4.6% vs 86% +/- 2.8%; P <.001) and risk for aneurysm-related death was increased (6.1% +/- 2.6% vs 1.5% +/- 1.0%; P =.011) in the group with large aneurysms. CONCLUSIONS: Outcome after endovascular repair of abdominal aortic aneurysm depends on size; results appear inferior in patients with larger aneurysms. These differences attain importance when choosing between observation and repair, balancing risk for rupture against size-dependent outcome.

Aged↗