Thomas S. Maldonado

Endovascular treatment of spontaneous dissections of the superior mesenteric artery

BACKGROUND Spontaneous dissection of the superior mesenteric artery (SMA) is exceedingly rare. Treatment options range from observation to anticoagulation to open surgery or endovascular repair. We present our experience to date in the management of isolated SMA dissections. METHODS A retrospective review of the vascular surgery and radiology databases from 1998 to 2008 was performed. In general, incidental radiologic findings of a dissection were managed expectantly. The decision to intervene was based on anatomic suitability, patient comorbidities and symptoms, and physician preference. Endovascular stents were placed using a brachial approach, with the choice of stent determined by physician preference. Patients who underwent endovascular stent placement (ESP) were maintained on antiplatelet therapy for 6 months postoperatively. Follow-up consisted of yearly office visits and adjunctive computerized tomography (CT) or magnetic resonance imaging (MRI) when clinically indicated. RESULTS CT or MRI imaging identified nine patients (7 men, 2 women) with an isolated SMA dissection. One patient also had a concomitant celiac artery dissection. Median age was 70 years (range, 46-73 years). Median follow-up time was 32 months (range, 13.8-62.5 months). Presentations included an incidental radiologic finding in three patients and acute onset abdominal pain in six. Treatment included expectant management in four patients, anticoagulation in two, and ESP in three. ESP was performed primarily in two patients and in a third patient after initial management with anticoagulation failed. The reduction in the diameter of the true lumen was significantly greater in patients treated with ESP vs patients who were successfully managed expectantly or with anticoagulation (F = 15.59, P < .005). No procedural complications were associated with ESP. CONCLUSIONS An isolated SMA dissection is a rare entity that may be managed successfully in a variety of ways based on clinical presentation. Endovascular stenting can be performed with good results and may be the preferred treatment in patients with symptomatic isolated SMA dissections.

Initial successful management of type I endoleak after endovascular aortic aneurysm repair with n-butyl cyanoacrylate adhesive

OBJECTIVE Transcatheter embolization with coils and other agents has been described as a treatment method for type II endoleak after endovascular aortic aneurysm repair (EVAR). Type I endoleak has not been treated commonly with such therapies, although most investigators believe they warrant definitive intervention. The liquid adhesive n-butyl 2-cyanoacrylate (n-BCA) is often used to treat congenital arteriovenous malformations. The objective of this study is to report our initial experience in treating type I endoleak with n-BCA and with a variety of other interventions. METHODS A retrospective review was performed of 270 patients who underwent EVAR at our institution between January 1994 and December 2002. Of these, 24 patients had type I endoleak (8.9%), diagnosed either intraoperatively (n = 13, 52%) or during follow-up (n = 12, 48%). Among these 24 patients, 17 had proximal leaks and the remaining 8 patients had distal leaks. These cases form the focus of this study. RESULTS Twenty-two leaks required endovascular intervention, with the following success rate: n-BCA, 12 of 13 cases (92.3%); extender cuffs, 4 of 5 cases (80%); coils with or without thrombin, 3 of 4 cases (75%). In one patient with persistent endoleak despite attempted endovascular intervention the device ultimately was surgically explanted, and the patient did well. Of six patients with endoleak initially managed expectantly, two eventually underwent attempts at definitive intervention, both with n-BCA. Three sealed spontaneously before definitive intervention could be performed; and in one 97-year-old patient who refused intervention, the aneurysm subsequently ruptured and the patient died. In total, 13 patients with type I endoleak underwent n-BCA transcatheter embolotherapy. No serious complications were directly related to this therapy. Colon ischemia developed in one patient, and was believed to be a result of thromboembolism during wire and catheter manipulation rather than n-BCA treatment. Twelve of these 13 leaks remain sealed at mean follow-up of 5.9 months (range, 0-19 months). CONCLUSION Our initial use of n-BCA occlusion suggests that it may be an effective and safe method of treatment of type I endoleak after EVAR. In particular, n-BCA embolotherapy may be especially useful in treating type I endoleak not amenable to placement of extender cuffs. Larger case series and longer follow-up are needed before this treatment is more broadly recommended. Type I endoleak after EVAR can be treated successfully with a variety of endovascular methods, and surgical explantation is rarely required.

Left subclavian artery coverage during thoracic endovascular aortic aneurysm repair does not mandate revascularization

OBJECTIVE This study assessed the risk of left subclavian artery (LSA) coverage and the role of revascularization in a large population of patients undergoing thoracic endovascular aortic aneurysm repair. METHODS A retrospective multicenter review of 1189 patient records from 2000 to 2010 was performed. Major adverse events evaluated included cerebrovascular accident (CVA) and spinal cord ischemia (SCI). Subgroup analysis was performed for noncovered LSA (group A), covered LSA (group B), and covered/revascularized LSA (group C). RESULTS Of 1189 patients, 394 had LSA coverage (33.1%), and 180 of these patients (46%) underwent LSA revascularization. In all patients, emergency operations (9.5% vs 4.3%; P=.001), renal failure (12.7% vs 5.3%; P=.001), hypertension (7% vs 2.3%; P=.01), and number of stents placed (1=3.7%, 2=7.4%, ≥3=10%; P=.005) were predictors of SCI. History of cerebrovascular disease (9.6% vs 3.5%; P=.002), chronic obstructive pulmonary disease (9.5% vs 5.4%; P=.01), coronary artery disease (8.5% vs 5.3%; P=.03), smoking (8.9% vs 4.2%) and female gender (5.3% men vs 8.2% women; P=.05) were predictors of CVA. Subgroup analysis showed no significant difference between groups B and C (SCI, 6.3% vs 6.1%; CVA, 6.7% vs 6.1%). LSA revascularization was not protective for SCI (7.5% vs 4.1%; P=.3) or CVA (6.1% vs 6.4%; P=.9). Women who underwent revascularization had an increased incidence of CVA event compared with all other subgroups (group A: 5.6% men, 8.4% women, P=.16; group B: 6.6% men, 5.3% women, P=.9; group C: 2.8% men, 11.9% women, P=.03). CONCLUSIONS LSA coverage does not appear to result in an increased incidence of SCI or CVA event when a strategy of selective revascularization is adopted. Selective LSA revascularization results in similar outcomes among the three cohorts studied. Revascularization in women carries an increased risk of a CVA event and should be reserved for select cases.

Outcome of carotid artery interventions among female patients, 2004 to 2005.

BACKGROUND The benefit of carotid endarterectomy (CEA) in female patients has been questioned by various randomized, prospective trials, particularly in asymptomatic cases; several have noted an increase in perioperative stroke among women after CEA. The outcome of carotid angioplasty and stenting (CAS) has not been extensively examined in women. This study examined the outcome of CEA and CAS in women vs men by using a national database. METHODS Outcomes of CEA and CAS were stratified by sex using discharge data from the Nationwide Inpatient Sample (NIS), Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality. The NIS was used to identify patient discharges that occurred during 2004 and 2005. Appropriate International Classification of Diseases, 9th Revision (ICD-9) procedure and diagnosis codes were used to identify CEA and CAS cases. Outcome measures included in-hospital perioperative stroke and death. Comparisons of demographics, procedures, and outcome were performed between men and women. Additional analysis was performed among women alone to attempt to identify whether improved outcome was noted with either procedure. RESULTS Of 54,658 procedures, 94.2% were CEA and 5.8% were CAS. Women comprised 42.3% of the analyzed cases. Women and men were equally likely to be symptomatic (5.3% vs 5.3%, P = .8). Women were significantly less likely to undergo CAS than men (5.4% vs 6.1%, P < .001). Women and men had equivalent rates of perioperative stroke when undergoing CEA (1.0% vs 1.0%, P = .9) and CAS (2.7% vs 2.0%, P = .2). Symptomatic women had a significantly higher rate of perioperative stroke overall than did symptomatic men (3.8% vs 2.3%, P = .03). Asymptomatic women had a significantly lower perioperative stroke rate after CEA than after CAS (0.9% vs 2.1%, P < .001). Rates of perioperative showed a trend favoring CEA vs CAS among symptomatic women (3.4% vs 6.2%, P = .1). CONCLUSIONS The concern regarding an increased perioperative stroke rate after CEA among asymptomatic women appears to be unfounded. The perioperative stroke rate among symptomatic women was higher than that of symptomatic men, but still well within the acceptable range for symptomatic patients undergoing a cerebrovascular intervention. Nationally, women underwent CAS significantly less frequently than did men. Outcome among women for perioperative stroke favored CEA over CAS, particularly in asymptomatic patients. CEA may be the preferred treatment in women seeking intervention for cerebrovascular disease, unless compelling reasons exist to perform CAS.

Presentation and management of carotid artery aneurysms and pseudoaneurysms

OBJECTIVE The objective of this study was to review a single-institution contemporary experience with extracranial aneurysms of the carotid artery. METHODS A retrospective review was conducted of patients evaluated for an aneurysm of the extracranial carotid artery from 2005 to 2010. Demographics, presentation, and operative management were reviewed. The mean follow-up was 22 months (range, 1-58 months). RESULTS Over the study period, 16 aneurysms and pseudoaneurysms were identified in 15 patients. Of these, 14 aneurysms (in six men and eight women with mean age of 63 years) underwent surgical repair. The mean aneurysm size was 2.45 cm (range, 0.8-5 cm). One aneurysm (7.1%) was associated with neurologic symptoms, and 13 were asymptomatic. The underlying etiology was trauma in five (35.7%), prior carotid endarterectomy in five (35.7%), and degenerative atherosclerosis in four (28.6%). Aneurysms were isolated to the common carotid artery in six (42.9%), internal carotid artery in five (35.7%), and carotid bifurcation in three (21.4%). Five patients underwent aneurysmectomy with primary repair, seven underwent repair with an interposition graft, one required an innominate to common carotid artery bypass, and one patient had a plication and patch angioplasty. No mortalities or neurologic events were documented within 30 days. One patient had transient cranial nerve palsy. One patient required reintervention at 4 months for stenosis of the bypass graft, and one patient died at 10 months from an unrelated condition. There were no neurologic events on follow-up. CONCLUSIONS Carotid artery aneurysms and pseudoaneurysms are uncommon and usually asymptomatic. Prior trauma and carotid surgery were common etiologies. The location of the aneurysms was equally distributed between the internal and common carotid arteries. Surgical repair was safe and effective with no significant morbidity or mortality and good midterm stroke prevention.

Outcome of endovascular repair of popliteal artery aneurysm using the Viabahn endoprosthesis.

OBJECTIVE This study reviews a single-center experience of endovascular popliteal aneurysm (PAA) repair. METHODS A retrospective review was performed to identify all endovascular PAA repairs performed between September 2004 and January 2011. RESULTS We identified 21 patients (mean age, 74 ± 9 years, 91% men) with PAAs (mean size, 2.89 ± 1.0 cm) in 26 limbs, of which 38% were symptomatic. All patients underwent endovascular repair with a Viabahn covered stent graft (W. L. Gore & Assoc, Inc, Flagstaff, Ariz). Postoperatively, all patients were maintained on antiplatelet therapy with clopidogrel or aspirin, or both. Mean follow-up was 22 ± 17 months (range, 1-57 months). One patient with one aneurysm was lost to follow-up. Primary and secondary patencies were both 91.2% at 1 year and were 85.5% and 91.2%, respectively, at 2 years. The limb salvage rate was 100%. Four stent graft failures occurred at a mean of 12.3 ± 11 months. One technical failure due to stent graft infolding required conversion to an open femoral-popliteal bypass. Three additional graft failures occurred in patients with poor (single-vessel) runoff. Compared with patients with two- or three-vessel runoff, the graft failure rate in patients with single-vessel runoff was statistically significant (P = .02). Two of the graft failures were successfully treated with open thrombectomy, and one required a tibial artery bypass for limb salvage. CONCLUSIONS Endovascular repair of PAAs is feasible and has acceptable midterm patency rates. Poor distal runoff predicted graft failure.

Controversies in the Management of Type 11 “Branch” Endoleaks Following Endovascular Abdominal Aortic Aneurysm Repair

Successful endovascular aortic aneurysm repair (EVAR) is often defined as complete exclusion of blood flow within the aneurysm sac. Perigraft flow, also known as endoleak, is the most common complication following EVAR. Attachment site related endoleaks (type 1) are generally considered to warrant some form of intervention due to the belief that they represent a risk for future rupture. Management of type 11 endoleaks, also known as branch or collateral endoleaks, is more controversial. Some advocate a policy of watchful-waiting whereas others treat all type 11 endoleaks as soon as they are discovered. The following review explores the controversies pertaining to the management, diagnosis and surveillance imaging, and treatment of type 11 endoleaks.

Ontogeny of activin B and follistatin in developing embryonic mouse pancreas: implications for lineage selection☆☆☆

Activin, a member of the transforming growth factor-beta superfamily, has been shown to be a critical regulator in exocrine and endocrine pancreas formation. The purpose of our study was to describe the ontogeny of activin B and its inhibitor, follistatin, in developing pancreas and to elucidate potential mechanisms for exocrine and endocrine lineage selection. Mouse embryonic pancreata were dissected at various ages (day 10 [E10.5] to birth [E18.5]), sectioned, and immunostained for activin B (one of two existing isomers, A and B), follistatin, insulin, and glucagon. In addition, reverse transcriptase-polymerase chain reaction was employed to determine the messenger RNA expression of follistatin in isolated pancreatic epithelia and mesenchyme of various ages. Activin B was first detected at E12.5 in epithelial ceils coexpressing glucagon. At E16.5 th ese coexpressors appeared as clusters in close proximity to early ducts. By E18.5 activin B was localized to forming islets where cells coexpressed glucagon and were arranged in the mantle formation characteristic of mature alpha cells. Follistatin was found to be ubiquitous in pancreatic mesenchyme at early ages by immunohistochemical analysis, disappearing sometime after E12.5. Follistatin reappeared in El85 islets and remains expressed in adult islets. Follistatin messenger RNA was first detected in epithelium at E11.5, preceding its protein expression in islets later in gestation. We propose that mesenchyme-derived follistatin inhibits epithelium-derived activin at early embryonic ages allowing for unopposed exocrine differentiation and relative suppression of endocrine differentiation. At later ages the decrease in the amount of mesenchyme relative to epithelium and the subsequent drop in follistatin levels liberates epithelial activin to allow differentiation of endocrine cells to form mature islets by the time of birth.

Laser Saphenous Ablations in More Than 1,000 Limbs With Long-Term Duplex Examination Follow-Up

BACKGROUND The goal of this study was to evaluate the duplex results of endovenous laser ablation in the treatment of incompetent great saphenous veins (GSV) and small saphenous veins (SSV) with at least 1-year follow-up. METHODS A retrospective registry was entered by 11 centers from Europe and America, organized by the International Endovenous Laser Working Group. Data concerning 1,020 limbs in patients with incompetence of the GSV and/or SSV, treated with the Endovenous Laser Ablation (EVLA) procedure, were collected. EVLA failures were defined on duplex imaging as reflux confined to the saphenofemoral or saphenopopliteal junction, reflux confined to the main saphenous trunk, or reflux of both junction and main trunk (totally patent saphenous vein) were analyzed at one or more years postoperatively. RESULTS The mean age of patients was 54 ± 5 years (range: 18-91 years). The average body mass index was 25. There was a paucity of severe complications: One case of third-degree skin burn, six patients with postsurgical deep vein thrombosis (0.6%), and 27 cases of sensory nerve damage (2.7%). At 1-year, the rate of complete occlusion of the saphenous trunk was 93.1%. There were 79 cases of treatment failures as evidenced by duplex: 22 isolated junction failures (2.2%), 44 isolated trunk failures (4.4%), and 13 totally patent veins (1.3%). Two-year duplex results were reported for 329 limbs with the identification of 19 new cases of failure. No new cases of failure were reported at 3-year follow-up of 130 limbs. Cumulative failure rates estimated by Kaplan-Meier analysis were 7.7% at 1-year and 13.1% at 2- and 3-year follow-up. CONCLUSIONS On the basis of a duplex scan performed at least 1-year post-treatment, this multicenter registry confirms the safety and efficacy of the EVLA procedure in the treatment of GSV and SSV reflux. Considering the continued failure rate documented in the present study, an annual follow-up by duplex is recommended to 2 years after EVLA.

Endovascular-first approach is not associated with worse amputation-free survival in appropriately selected patients with critical limb ischemia

OBJECTIVE Endovascular interventions for critical limb ischemia are associated with inferior limb salvage (LS) rates in most randomized trials and large series. This study examined the long-term outcomes of selective use of endovascular-first (endo-first) and open-first strategies in 302 patients from March 2007 to December 2010. METHODS Endo-first was selected if (1) the patient had short (5-cm to 7-cm occlusions or stenoses in crural vessels); (2) the disease in the superficial femoral artery was limited to TransAtlantic Inter-Society Consensus II A, B, or C; and (3) no impending limb loss. Endo-first was performed in 187 (62%), open-first in 105 (35%), and 10 (3%) had hybrid procedures. RESULTS The endo-first group was older, with more diabetes and tissue loss. Bypass was used more to infrapopliteal targets (70% vs 50%, P = .031). The 5-year mortality was similar (open, 48%; endo, 42%; P = .107). Secondary procedures (endo or open) were more common after open-first (open, 71 of 105 [68%] vs endo, 102 of 187 [55%]; P = .029). Compared with open-first, the 5-year LS rate for endo-first was 85% vs 83% (P = .586), and amputation-free survival (AFS) was 45% vs 50% (P = .785). Predictors of death were age >75 years (hazard ratio [HR], 3.3; 95% confidence interval [CI], 1.7-6.6; P = .0007), end-stage renal disease (ESRD) (HR, 3.4; 95% CI, 2.1-5.6; P < .0001), and prior stroke (HR, 1.6; 95% CI, 1.03-2.3; P = .036). Predictors of limb loss were ESRD (HR, 2.5; 95% CI, 1.2-5.4; P = .015) and below-the-knee intervention (P = .041). Predictors of worse AFS were older age (HR, 2.03; 95% CI, 1.13-3.7; P = .018), ESRD (HR, 3.2; 95% CI, 2.1-5.11; P < .0001), prior stroke (P = .0054), and gangrene (P = .024). CONCLUSIONS At 5 years, endo-first and open-first revascularization strategies had equivalent LS rates and AFS in patients with critical limb ischemia when properly selected. A patient-centered approach with close surveillance improves long-term outcomes for both open and endo approaches.