George K. Lee

Shuttering of the superior mesenteric artery during fenestrated endovascular aneurysm repair

OBJECTIVE Shuttering occurs when a scallop or fenestration does not align perfectly with the target vessel ostium and is potentially minimized by stenting. The current United States Food and Drug Administration-approved fenestrated endovascular aneurysm repair (f-EVAR) device is most commonly configured with an unstented superior mesenteric artery (SMA) scallop, thereby subjecting the SMA to risk of partial coverage. We aimed to describe the incidence, severity, and clinical effect of SMA shuttering during f-EVAR. METHODS Patients undergoing f-EVAR using the commercially available Zenith (Cook Medical, Bloomington, Ind) fenestrated stent graft system containing an SMA scallop at our institution between September 2012 and January 2014 were included for analysis. Corrected multiplanar reformatted images on postoperative computed tomographic angiography were reviewed to measure SMA shuttering, defined as the percentage of scallop misalignment relative to the SMA ostial diameter. RESULTS Of the 28 f-EVAR cases performed at our institution during the study period, 18 patients (78% male) had an SMA scallop and were included in this analysis. The median age was 78 years (interquartile range [IQR], 72-81 years), and the median abdominal aortic aneurysm size was 61 mm (IQR, 56-64 mm). Fifty-one vessels were targeted (18 SMA scallops, 32 renal fenestrations, 1 renal snorkel), with covered stents placed in all fenestrations. Target vessel catheterization and successful branch stent deployment was achieved in 100% of patients. SMA shuttering measured on postoperative computed tomographic angiography of any amount occurred in 50% of patients (range of SMA shuttering, 12%-40%). The severity of SMA shuttering varied: one patient had 11% to 20%, four had 21% to 30%, and four had 31 to 40%. When compared with patients without shuttering, patients with any SMA shuttering were noted to have a shorter infra-SMA neck length (17 vs. 25 mm; P = .007), higher volume of intraprocedural contrast administration (100 vs. 66 mL; P = .001), and had a trend toward longer procedural durations (240 vs. 188 minutes; P = .09). No association was found between SMA shuttering and the preoperative measured clock position of the visceral vessels, percentage of device oversizing, number of target vessels per patient, aortic diameter at the SMA or seal zone, aneurysm neck morphology, infrarenal neck length, scallop width, or SMA ostial diameter. No acute or chronic events of mesenteric ischemia were noted during a median clinical follow-up period of 11 months (IQR, 5-14 months). CONCLUSIONS Even with the custom design of currently available fenestrated technology, shuttering of the SMA occurred in one-half of the patients in our cohort, although no clinical events were noted. Further details of the incidence, magnitude, and tolerance of SMA shuttering during f-EVAR are warranted to fully understand the clinical implication of this radiographic finding. Future design considerations for advanced EVAR should take into account SMA shuttering to further refine operative planning.

Intravascular ultrasound as a clinical adjunct for carotid plaque characterization

OBJECTIVE Virtual histology intravascular ultrasound (VH IVUS) is valuable for estimating minimal lumen diameter and plaque characterization. The clinical use of IVUS in carotid intervention is not well characterized. We aim to evaluate the role of IVUS in carotid plaque characterization and determine whether it could be predictive of procedure-related microemboli. METHODS From July 2010, patients with severe carotid stenosis who underwent elective carotid stenting procedures were prospectively enrolled. IVUS evaluation was performed before stent placement. Patient demographics, comorbidities, and preoperative images were recorded. Comparison of pre- and postoperative diffusion-weighted magnetic resonance images was used to identify the number of procedure-related microemboli. IVUS-derived minimal lumen diameter and vessel wall plaque characteristics were collected. Univariate and multivariate logistic regressions were used to search for associations between IVUS-derived VH data and incidence of microemboli. RESULTS A total of 38 high-risk patients receiving carotid stenting were enrolled. Among them, 25 patients had type I aortic arches and 17 of the patients were symptomatic (preoperative stroke or transient ischemic attack). VH IVUS data did not show strong associations with microemboli, however, a trend was found between the area of fibrous tissue and median or more incidence of microemboli (P = .099). IVUS-defined vessel diameter maximum was associated with median or more incidence of microemboli (P = .042). In addition, median or more incidence of microemboli showed trends with proximal common carotid artery calcification (P = .056) and with being over the age of 80 (P = .06). Contralateral carotid occlusion or high-grade stenosis was associated with postoperative contralateral microemboli (P = .036). CONCLUSIONS We demonstrate that periprocedural carotid IVUS is clinically feasible. VH IVUS may be helpful in better understanding plaque morphology and determining optimal stent placement. However, its use in predicting microembolization remains limited.

Elective EVAR in Nonagenarians Is Safe in Carefully Selected Patients

BACKGROUND Nonagenarians are typically considered poor operative candidates for major aortic intervention because of shorter life expectancy, multiple comorbidities, and increased perioperative morbidity and mortality. Endovascular abdominal aortic aneurysm repair (EVAR) has clearly been associated with a lower perioperative morbidity and mortality in most anatomically suitable patients. There have been many reports of the technical success of EVAR in octogenarians, but few documenting EVAR in nonagenarians. In this study, we sought to review our experience with elective EVAR in nonagenarians to determine outcomes, complications, and long-term survival after repair. METHODS We retrospectively reviewed our prospectively maintained aneurysm database from 2000 to 2010 at an academic referral center. Fifteen patients ≥90 years old underwent elective EVAR. No symptomatic or ruptured abdominal aortic aneurysm patients >90 years old were treated. Comorbidities, preoperative and postoperative functional status, aneurysm size, and technical success rate were all recorded in accordance with Society for Vascular Surgery reporting guidelines. Follow-up was performed within 30 days, 6 months, and annually thereafter unless more frequent follow-up was indicated. RESULTS Of the 749 EVAR procedures performed in the decade-long experience, 15 nonagenarians underwent repair (14 male, 93%; mean age, 90.3 ± 0.6 years). Mean aneurysm diameter was 6.4 ± 1.45 cm with a median diameter of 5.8 cm (range 4.5-8.8 cm). All patients were offered repair because of having good to excellent preoperative functional status with an average number of comorbidities per patient of 2.7. Immediate technical success rate was 100%. Median intensive care unit stay was 1 day (range 1-17 days). Mean length of stay was 4.6 ± 5.3 days with a median of 3.5 days. Thirty-day mortality was 0%. Mean follow-up was 35 months. Mean survival was 56 months. Overall survival estimated annually extending out to 5 years was 91.7%, 83.3%, 71.4%, 57.1%, and 38.1%, respectively. Thirty-day rate of any complication was 40%, with a 20% readmission rate, with many of the issues being related to wound complications. On follow-up imaging there were noted to be 4 (27%) type I, 9 (60%) type II, and no type III or type IV endoleaks identified. Overall reintervention rate was 27%. No ruptures were noted in the postoperative period or long-term follow-up, and there were no conversions to open surgery. CONCLUSIONS We found a median survival of 56.2 months in this carefully selected cohort of EVAR in nonagenarians. As techniques and technology improve and evolve, and particularly as devices become lower profile, there is the potential to apply EVAR to the increasingly older population. If perioperative morbidity can be minimized and the patient has good functional status, EVAR can be a safe procedure and provide rupture-free survival.

Infected Aortic Stent Graft With Propionibacterium acnes

An infected aortic endograft is an uncommon event, and when it happens it can be of significant morbidity and mortality to the patient. We present here a case of a patient with an infected aortic endograft following percutaneous translumbar sac embolization for a type II endoleak leading to sac expansion. The cultured pathogen was Propionibacterium acnes, a commonly occurring skin bacterium that leads to the clinical condition “acne vulgaris.” The patient underwent graft explantation and reconstruction with autogenous femoral vein. To our knowledge, there are no previously published reports of aortic graft infections with P acnes.

A Vascular Quality Initiative-Based Frailty Instrument Predicts 9-Month Postoperative Mortality

aortic injury related), and four patients died after 30 days (one related to aortic injury due to an esophageal-aortic fistula; three unrelated). Freedom from all-cause mortality and aortic injury-related mortality at 1 year was 89.3% and 92.8%, respectively. Two cases of stroke occurred within 30 days, and no strokes were reported beyond 30 days. In total, six patients underwent reintervention for thrombus, device compression, residual injury, endoleak, dissection, and pseudoaneurysm. Only one patient underwent surgical conversion (181 days after the procedure) following a failed reintervention for a site-reported proximal type I endoleak. No patient experienced aortic rupture. Among 31 patients with available core laboratory review of computed tomography imaging at 1 year, aortic injury healing (ie, the absence of aortic injury) was confirmed in 96.8% (30/31) of patients and patency was observed in 100% (31/31) of patients. No type I or type III endoleak, component separation, device migration, or device integrity issues have been observed on the basis of core laboratory imaging review to date. Conclusions: Updated outcomes indicate that the Zenith Alpha Thoracic Endovascular Graft continues to perform safely and effectively for the treatment of BTAIs.

A prospective evaluation of using IVUS during percutaneous superficial femoral artery interventions.

BACKGROUND The outcomes of endovascular interventions of the superficial femoral artery (SFA) are variable. Completion angiography is typically performed to confirm satisfactory outcomes after SFA angioplasty and/or stenting. However, two-dimensional angiography may not accurately reflect the extent of residual stenosis. We sought to determine whether intravascular ultrasound (IVUS) can help with residual disease assessment and procedure outcome. METHODS Patients with anticipated SFA disease were prospectively recruited to the study. Patients with primary SFA disease on diagnostic angiography were included. After SFA endovascular intervention with angioplasty and/or stenting, a completion angiogram was performed to confirm satisfactory results before IVUS evaluation. IVUS-detected maximal residual stenosis, maximal residual lesion volume, and number of nonconsecutive posttreatment SFA segments with >50% residual stenosis were evaluated. Periprocedural ankle-brachial indexes (ABIs), Short Form 36 (SF-36) surveys, and Walking Impairment Questionnaires were also collected. RESULTS Fifty-nine patients were prospectively enrolled. Thirty-three received angioplasty only, and 26 received angioplasty and stenting. All patients were men, mean age was 67 years, and major comorbidities included coronary artery disease (53%), active smoking (56%), hypertension (88%), and diabetes (68%). The angioplasty-only cohort had more nonconsecutive areas of >50% residual stenosis (P = 0.004), greater residual stenosis (P = 0.03), and smaller minimal lumen diameters after treatment (P = 0.01) than the angioplasty and stenting cohort. However, there was no significant difference in ABI between the 2 groups and no difference in ABI improvement after intervention. Sixty-four percent of all patients demonstrated a >0.2 increase in postintervention ABI. Improvement in ABI at 1 month after procedure significantly correlated with postintervention SF-36 survey physical scores (r = 0.435, P = 0.007). CONCLUSIONS IVUS evaluation provides more-accurate intraprocedural insight on the extent of residual stenosis after SFA interventions. Future studies are warranted to determine whether IVUS-guided postangioplasty and/or stenting can impact long-term interventional outcome.

Reentry Device Aided Endovascular Aneurysm Repair in Patients with Abdominal Aortic Aneurysm and Unilateral Iliac Artery Occlusion

BACKGROUND We report 2 cases of patients undergoing endovascular aneurysm repair (EVAR) using reentry devices to recanalize unilateral iliac artery occlusions and complete a bifurcated endovascular repair. METHODS Patient 1 is a 70-year-old male with an enlarging 6.5-cm abdominal aortic aneurysm (AAA) and disabling left leg claudication with L external iliac occlusion with patent common and internal iliac arteries. Patient 2 is a 67-year-old male with an asymptomatic 4.0-cm AAA and L iliac chronic total occlusion (CTO) and disabling claudication. Both patients were poor operative candidates for open repair. RESULTS Both patients underwent elective percutaneous EVAR along with left iliac artery revascularization. Initial angiography in both cases showed a blind ending of the left common iliac artery. Retrograde subintimal dissection through the occluded iliac segment was attempted but in both cases the wire was unable to traverse back into the true aortic lumen. Using either the Outback LTD or Pioneer reentry catheter, direct visualization of the true aortic lumen was obtained to re-enter the true lumen. The subintimal iliac tract was then predilated to facilitate routine EVAR in both cases. Both patients were discharged the following day and 1-year and 6-month follow-up imaging revealed aneurysm exclusion, no endoleak, and patent bilateral common iliac arteries with resolution of claudication symptoms and normal ankle-brachial indexes. The previously patent internal iliac artery was preserved. CONCLUSIONS While not always technically possible, reentry device aided EVAR is safe, feasible, and durable in the mid-term and avoids the morbidity and mortality related to aortouniiliac/femoral-femoral bypass and open repair. This technique should be considered in patients with iliac artery CTO and concurrent AAA to allow total endovascular repair.

Delayed Hypogastric Artery Pseudoaneurysm Following Blunt Trauma Without Evidence of Pelvic Fracture

Arterial pelvic bleeding caused by bony fragments is a common finding in patients with pelvic fractures after blunt trauma (Durkin et al., Am J Surg 2006;192:211-23). However, arterial injury in the absence of bony fracture is extremely rare, and in the event that it does occur, is immediately discovered on cross-sectional imaging. We present an unusual case of a 15-year-old boy who was involved in a bicycle accident, and who, a week after his injury, developed a delayed hypogastric branch artery pseudoaneurysm causing sciatic nerve compression with a right foot drop. Initial magnetic resonance imaging scan and pelvic X-ray at the time of the injury showed no evidence of pelvic fracture or vascular damage. The pseudoaneurysm was successfully treated with selective coil embolization and hematoma evacuation. This study represents only the second reported case of delayed pelvic pseudoaneurysm in the absence of pelvic fracture.