Danielle M. Pineda

The fate of endovascular aortic aneurysm repair after 5 years monitored with duplex ultrasound imaging

Background: Interventions for aortic aneurysm sac growth have been reported across multiple time points after endovascular aortic aneurysm repair (EVAR). We report the long‐term outcomes of patients after EVAR monitored with duplex ultrasound (DUS) imaging with respect to the need for and type of intervention after 5 years. Methods: We report a series of patients who were monitored with DUS imaging for a minimum of 5 years after EVAR. DUS imaging was performed in an accredited noninvasive vascular laboratory, and computed tomography angiography was only performed for abnormal DUS findings. Results: There were 156 patients who underwent EVAR with follow‐up >5 years (mean, 7.5 years; range, 5.1‐14.5 years). Interventions for endoleak, graft limb stenosis, or thrombosis were performed in 44 patients (28%) at some time during follow‐up. Of the 156 patients, 34 (22%) underwent their first intervention during the first 5 years (25 endoleaks, 9 limb stenoses, or occlusions). Four ruptures occurred, all in patients with their first intervention before 5 years. The remaining 10 patients (6%) underwent a first intervention >5 years after implantation: 3 for type I endoleak, 2 for type II endoleak with sac expansion, 2 for combined type I and II endoleaks 2 for type III endoleak, and 1 unknown type. Conclusions: Long‐term follow‐up of EVAR (mean, 7.5 years) revealed that approximately one in four patients will require intervention at some point during follow‐up. First‐time interventions were necessary in 22% of all patients in the first 5 years and in 6% of patients after 5 years, highlighting the need for continued graft surveillance beyond 5 years. All patients who had a first‐time intervention after 5 years underwent an endoleak repair; none of these patients had a thrombosed limb or a rupture as a result of the endoleak.

Bovine carotid artery xenografts for hemodialysis access

Objective: Bovine carotid artery (BCA) grafts have been described as a possibly superior alternative to expanded polytetrafluoroethylene hemoaccess grafts. However, published experience remains limited, and patency rates for nonautogenous arteriovenous grafts remain unsatisfactory. We report herein the largest published experience with the current generation of BCA grafts for dialysis access and analyze subgroups to determine whether obesity, gender, or prior access surgery influences patency. Methods: We retrospectively reviewed 134 BCA grafts (Artegraft, North Brunswick, NJ) implanted for hemodialysis access in the upper extremities of 126 patients between January 2012 and May 2015. Patients had a mean of 1.8 prior access operations. Primary, primary assisted, and secondary patency rates were calculated using the Kaplan‐Meier method, and longitudinal infection risk was tabulated. Patency differences were calculated using the log‐rank method. Results: For the entire group, 1‐year primary patency was 32%, primary assisted patency was 49%, and secondary patency was 78%. Ten of 133 grafts (7%) developed infection requiring graft excision between 1 and 9 months after implantation. There was no statistical difference between men and women in primary or secondary patency (P = .88, P = .69). There was no difference in primary patency or secondary patency for patients with body mass index >30 or <30 (P = .85, P = .54). Patients who had a BCA graft as their first access attempt had a higher primary and primary assisted patency than that of patients who had the graft placed after prior access failure (P = .039, P = .024). Conclusions: This represents the largest published series of BCA grafts for arteriovenous grafts in the modern era. The primary patency of BCA grafts in this series was lower than that reported in a smaller randomized study. However, primary assisted and secondary patency were similar. Infection rates in this series appear to be somewhat lower than polytetrafluoroethylene infection rates reported in the literature. BCA grafts are a satisfactory alternative to expanded polytetrafluoroethylene for hemodialysis access, but larger controlled studies are needed to determine whether superior primary patency previously reported is a reproducible finding.

Duplex Ultrasonography and its Use in Surveillance Post-EVAR

After endovascular aortic aneurysm repair (EVAR), patients require annual surveillance with either CT scan or duplex ultrasonography (DU). These studies should be used to identify patients who require reintervention for EVAR complications. DU, a less expensive and radiation free option, has been shown to accurately predict aneurysm sac size and endoleak. In addition, using criteria of PSV<300 cm/s and PSV ratio <3.5, DU can rule out limb stenosis. After a normal post-procedure DU, only 2.2% of patients require reintervention within the first 3 years suggesting that less frequent follow-up may be utilized. DU is an important tool in the surveillance of EVAR patients.

Endovascular Repair of Three Concurrent Mycotic Pseudoaneurysms

Introduction: Mycotic pseudoaneurysm has traditionally been repaired surgically with excision of the infected artery and revascularization via extra-anatomical or in situ bypass. There have been reports of endovascular repair for high-risk patients for formal surgical repair. We present a case of a patient with 3 large pseudoaneurysms arising from the right subclavian artery, descending thoracic aorta, and right popliteal artery treated with endovascular and hybrid intervention. Case: A 74-year-old male with remote history of coronary artery bypass graft and recent sternoclavicular joint abscess developed 3 concurrent pseudoaneurysms arising from the right subclavian artery, distal descending thoracic aorta, and right popliteal artery. He underwent right axillary to common carotid bypass with endovascular stent graft placement in the distal innominate and proximal subclavian artery, and subsequently had thoracic endovascular aortic repair and right popliteal stent graft. Four months later, he presented with hemoptysis due to compression of the lung secondary to the pseudoaneurysm. He underwent right anterior thoracotomy and debridement of the pseudoaneurysm. Patient recovered from the procedure and discharged. Conclusion: Endovascular repair of mycotic pseudoaneurysm is an acceptable alternative for high-risk patients. Even when open approach became necessarily, endovascular stent graft decreased blood loss and morbidity.

Patient satisfaction and chronic illness are predictors of postendovascular aneurysm repair surveillance compliance

Objective Although lifelong surveillance is recommended by the Society for Vascular Surgery for patients undergoing endovascular aneurysm repair (EVAR) reported that compliance with long‐term follow‐up has been poor. We sought to identify factors that predict compliance with EVAR surveillance through analysis of patient variables and post‐EVAR questionnaire results. Methods We analyzed 28 patient variables gathered from our computerized registry, patient charts, and phone questionnaires of patients who underwent EVAR between January 1, 2010, and December 31, 2014. These factors included patient demographics, education, postoperative complications, satisfaction with vascular surgery care, transportation mode, distance to our medical center, and living situation. Compliance was defined as a patient who underwent the most recent recommended follow‐up surveillance study within the prescribed timeframe. Post‐EVAR surveillance protocol consisted of office evaluation and duplex ultrasound examination performed in our accredited noninvasive vascular laboratory at 1 week, 6 months, then annually. Computed tomography angiography was obtained only if duplex ultrasound examination suggested endoleak, sac enlargement of more than 5 mm, or a failing limb. Results Of 144 patients who underwent EVAR during this time period, 89 patients (62%) were compliant with the most recent recommended follow‐up study. One hundred two patients completed the questionnaire or their families did if patients died or were incapacitated. Of those, 80 were compliant with follow‐up and 22 were not. Based on the questionnaires of these 102 patients, estimated compliance at 3 years after EVAR was 69.6 ± 6.0% based on Kaplan‐Meier analysis. In the compliant vs noncompliant groups, the estimated 3‐year survival rate was 93.2 ± 3.4% vs 52.4 ± 12.7%, respectively (P < .001), and the estimated 5‐year survival rate was 83.1 ± 6.4% vs 34.4 ± 13.4%, respectively (P < .001), respectively. However, none of the mortalities observed in the noncompliant group were aneurysm related. Adverse neurologic events after EVAR demonstrated a trend predicting noncompliance after 5 years based on multivariate Cox regression analysis (hazard ratio [HR], 2.57; 95% confidence interval [CI], 0.95‐6.90; P = .062). Patient dissatisfaction with their vascular surgeon and hospital care predicted noncompliance with recommended postoperative surveillance (HR, 5.0; 95% CI, 1.52‐16.7; P = .008). College education or higher was associated with compliance (HR, 0.28; 95% CI, 0.06‐1.23; P = .092). No other variables, including postoperative complications or distance from the hospital, predicted follow‐up noncompliance. Conclusions Patient satisfaction with their vascular surgeon and hospital experience predicted compliance with post‐EVAR surveillance regardless of postoperative complications. Noncompliant patients had decreased survival, but mortality and surveillance noncompliance were likely due to disabling chronic disease.

Low carotid stump pressure as a predictor for ischemic symptoms and as a marker for compromised cerebral reserve in octogenarians undergoing carotid endarterectomy

Background: Carotid artery occlusive disease can cause stroke by embolization, thrombosis, and hypoperfusion. The majority of strokes secondary to cervical carotid atherosclerosis are believed to be of embolic etiology. However, cerebral hypoperfusion could be an important factor in perioperative stroke. We retrospectively reviewed the stump pressure (SP) of carotid endarterectomy (CEA) of patients at Pennsylvania Hospital to identify whether physiologic perfusion differences account for differences in perioperative stroke rates, particularly in octogenarians. Methods: We conducted a retrospective review of our prospectively maintained database for CEA performed between 1992 and 2015. SP was measured and recorded for 1190 patients. A low SP was defined as systolic pressure <50 mm Hg. Shunts were used only for patients under general anesthesia with SP <50 mm Hg, for awake patients with neurologic changes with carotid clamping, and in some patients with recent stroke. Results: Symptomatic patients were more likely to have SP <50 mm Hg compared with asymptomatic patients (35.6% vs 26.2%; P = .0015). Patients having SP <50 mm Hg had a higher postoperative stroke rate compared with patients with SP >50 mm Hg (2.9% vs 0.9%; P = .0174). Octogenarians were more likely to have a lower SP compared with patients younger than 80 years (35.7% vs 27.7%; P = .0328). Symptomatic patients with low SP were at highest risk for perioperative stroke (6.4% vs 1.2%; P = .001) compared with patients without these factors. Conclusions: SP is a marker for decreased cerebrovascular reserve and along with symptomatic status identifies those at highest risk for periprocedural stroke with CEA. Whereas patients older than 80 years may benefit from carotid intervention, they are likely to be at somewhat elevated stroke risk because of higher prevalence of low SP, and shunting does not eliminate this risk.

A Novel Method for the Treatment of Bilateral Hypogastric Aneurysms Using Hybrid Polytetrafluoroethylene Graft

Open aortic aneurysm repair in the setting of bilateral hypogastric aneurysms is technically challenging. We present a novel technique for open surgical repair for bilateral hypogastric aneurysms using the Gore hybrid vascular graft (GVHG; W. L. Gore and Associates Inc, Flagstaff, Arizona). The GVHG is an expanded polytetrafluoroethylene graft with a nitinol stent at 1 end designed for hemodialysis access. The GVHG has been also been used for aortic debranching and treatment of occlusive disease. We describe the first report using GVHG to repair hypogastric aneurysms.

Variability in 2-year training programs in vascular surgery based on results of an Association of Program Directors in Vascular Surgery survey

Objective: Although a great deal of attention has recently focused on 5‐year integrated (0+5) training programs in vascular surgery, a paucity of data exists concerning variability of daily assignments in 2‐year (5+2) vascular fellowships. Methods: We polled Association of Program Directors in Vascular Surgery members with 2‐year vascular fellowships to determine the number of days in a 5‐day work week that first‐ and second‐year fellows were assigned to open vascular operations, endovascular procedures (hospital vs nonhospital facility), arterial clinic, venous clinic, noninvasive vascular laboratory (NIVL), and research. Results: Of the 103 program directors from 5+2 vascular training programs, 102 (99%) responded. The most common schedule for both first‐ and second‐year fellows was performing both open and endovascular procedures in the hospital on the same day 4 days of the week and spending time in combined artery and vein clinic 1 day of the week. Program directors developed different schedules for each year of the 2‐year fellowship in about half (55% [56]) of the programs. A small minority of programs devoted days to only open surgical cases (13% [13]), a separate venous clinic (17% [17]), or a separate arterial clinic (11% [11]) and performed endovascular procedures in a nonhospital facility (15% [15]). All but three programs had mandatory time in clinic both years. Approximately one‐third (30% [31]) of programs designated time devoted to research, whereas the others expected fellows to find time on their own. Although passing the Registered Physician in Vascular Interpretation examination is required, there was devoted time in the NIVL in only 60% (61) of programs. Conclusions: Training assignments in terms of time spent performing open and endovascular procedures and participating in clinic, the NIVL, and research varied widely among Accreditation Council for Graduate Medical Education‐accredited 5+2 vascular fellowships and did not always fulfill Accreditation Council for Graduate Medical Education guidelines. In the current era of emphasis on endovascular‐based interventions, few programs devoted days to purely open surgical procedures. Endovascular experience in a nonhospital facility (where these procedures will likely become more common in the future), outpatient venous procedures, and designated time devoted to the NIVL and research were lacking in many programs. These results provide a valid data set for the Association of Program Directors in Vascular Surgery to consider establishing guidelines for training assignments in 5+2 vascular training programs.

Surveillance Duplex Ultrasonography of Stent Grafts for Popliteal Aneurysms.

Objective: Stent grafts, also known as covered stents, have become an increasingly acceptable treatment for popliteal artery aneurysms. However, endovascular exclusion confers lower primary patency compared to traditional open bypass and exclusion. The purpose of this study was to evaluate whether duplex ultrasonography (DU) can reliably diagnose failing stent grafts placed for popliteal artery aneurysms prior to occlusion. Methods: Between June 5, 2007, and March 11, 2014, 21 stent grafts (Viabahn; Gore, Flagstaff, Arizona) were placed in 19 patients for popliteal artery aneurysms. All patients had at least 1 follow-up duplex scan postoperatively. Mean follow-up was 28.9 months (9-93 months). Postoperative DU surveillance was performed in our Intersocietal Accreditation Commission noninvasive vascular laboratory at 1 week postprocedure and every 6 months thereafter. Duplex ultrasonography measured peak systolic velocities (PSVs) and ratio of adjacent PSVs (Vr) every 5 cm within the stent graft and adjacent arteries. Results: We retrospectively classified the following factors as “abnormal DU findings”: focal PSV > 300 cm/s, uniform PSVs < 50 cm/s throughout the graft, and Vr > 3.0. These DU criteria were derived from laboratory-specific data that we previously published on failing stent grafts placed for lower extremity occlusive disease. Four of the 21 stent grafts presented with symptomatic graft thrombosis within 6 months of a normal DU. Three of these 4 patients presented with rest pain and underwent thrombectomy (2) or vein bypass (1), and 1 elected for nonintervention for claudication. Conclusion: Our results suggest that surveillance DU using criteria established for grafts placed for occlusive disease may not be useful for predicting stent graft failure in popliteal artery aneurysms.

Thoracic Aortic Graft Infections Secondary to Propionibacterium Species Two Cases and Review of the Literature

Aortic graft infections are a rare occurrence, most commonly secondary to gram-positive organisms (Staphylococcus and Streptococcus species). We present 2 cases of thoracic aortic graft infections secondary to anaerobic bacteria, Propionibacterium species. The first case, a 40-year-old male, was found to have an anastomotic aneurysm at the distal anastomosis of a previous thoracoabdominal aneurysm repair. During the open repair of his anastomotic aneurysm, the original graft was not incorporated and cultures later speciated Propionibacterium acnes. The second case is a 44-year-old male with a history of abdominal aortic coarctation that was repaired with a thoracic aorta to aortic bifurcation graft as a child who presented with flank pain and was found on imaging to have fluid around his bypass graft. His operating room (OR) cultures also grew out Propionibacterium species. Both patients were treated with graft excision, revascularization, and long-term antibiotics. Anaerobic bacteria are a rare cause of aortic graft infections. Upon review of the literature, these are the first 2 cases of thoracic aortic graft infections secondary to Propionibacterium species. The cultures for both patients took almost a week to speciate, highlighting the importance of following cultures long term. Anaerobic bacteria should be recognized as a cause of latent graft infections.