Single-center experience with complex abdominal aortic aneurysms treated by open or endovascular repair using fenestrated/branched endografts.

OBJECTIVE: The objective of this study was to evaluate outcomes of patients with complex abdominal aortic aneurysms (cAAAs) treated with open repair (OR) or fenestrated/branched endovascular aneurysm repair (F/B-EVAR) from a single center. METHODS: A retrospective analysis of consecutive patients with cAAAs treated electively by OR or F/B-EVAR between January 2010 and February 2017 was conducted. Demographics of the patients, cardiovascular risk factors, procedure time, number of vessels incorporated, radiation dose, estimated blood loss, intensive care unit (ICU) length of stay (LOS), and hospital LOS were recorded. End points included target vessel patency, aneurysm rupture, freedom from reintervention, and major adverse events (MAEs). RESULTS: During this period, 153 patients (OR, 69; F/B-EVAR, 84) underwent repair of cAAA. The majority were male (OR, 55; F/B-EVAR, 64), with a mean age of 75.8 ± 7.6 years (F/B-EVAR) and 71.2 ± 7.9 years (OR). Patients in the F/B-EVAR group were more likely to be American Society of Anesthesiologists class 3 and 4 (60% vs 0%; P < .001) and had a higher median Society for Vascular Surgery/American Association for Vascular Surgery comorbidity severity score (15 vs 7; P < .001). A total of 235 vessels were targeted in the F/B-EVAR group, with a technical success of 97.6%. Thirty-one patients in the OR group required concomitant renal artery revascularization. Transfusion requirements (100% vs 1.2%), MAEs (40.6% vs 13.1%), procedure length (304 minutes vs 140 minutes), estimated blood loss (2246 mL vs 165 mL), ICU LOS (3 days vs 1 day), and hospital LOS (7 days vs 2 days) were higher (P < .001) in the OR group compared with the F/B-EVAR group. The 30-day mortality was 2.9% and 2.4% (P = .84) in the OR group and F/B-EVAR group, respectively. Supraceliac clamp site was associated with increased incidence of postoperative renal insufficiency. A decrease in procedure time, contrast volume, fluoroscopy time, and fluoroscopy dose was noted in the F/B-EVAR group with increasing experience even as case complexity increased. More patients were discharged home after F/B-EVAR (97.6% vs 59.4%; P < .001). With a mean follow-up of 31 months (F/B-EVAR, 17 months; OR, 48 months), the rate of secondary intervention was 3.7% and 5.8% (P = NS) for F/B-EVAR and OR, respectively. Freedom from branch instability and reintervention was 99% (95% confidence interval, 96.2%-99.8%) and 96% (95% confidence interval, 87.1%-98.6%), respectively. CONCLUSIONS: Results of this "real-world" experience suggest that the use of F/B-EVAR for the treatment of cAAAs in high-risk surgical patients is safe and effective and has comparable short-term results to those of low-risk patients undergoing OR. Patients treated by F/B-EVAR had shorter ICU and hospital LOS, lower MAEs, and faster convalescence. A decrease in procedure time and radiation dose was noted as experience was gained, even as complexity increased.

Diagnosis, Management, and Outcome of Aortitis at a Single Center.

BACKGROUND: Aortitis is a rare condition with inflammatory or infectious etiology that can be difficult to diagnose due to the highly variable clinical presentation and nonspecific symptoms. However, current literature on the diagnosis, management, and prognosis of aortitis is extremely scarce. METHODS: We retrospectively reviewed all patients' charts who were diagnosed with giant cell arteritis, Takayasu arteritis, or noninfectious aortitis presenting at a single center between January 1, 2009, and April 17, 2015. Data collected included demographics, medical history, comorbidities, laboratory and imaging data, management, and outcome. RESULTS: Among the included 15 patients presenting with aortitis at our center, 53% were diagnosed with Takayasu arteritis, 33% with idiopathic inflammatory aortitis, and 13% with giant cell arteritis. All patients received steroid treatment, 67% received adjunctive immunosuppressants or immunomodulators, and 33% underwent interventional procedures. Based on clinical presentation and laboratory and imaging findings at the last follow-up visit for each patient, 67% showed improvement, 27% had no change in disease activity, and 7% had a progression of the disease. CONCLUSIONS: Takayasu arteritis was found to be more common than idiopathic inflammatory aortitis and giant cell arteritis among our 15 cases diagnosed with aortitis. All patients received medical therapy and 33% received interventional procedures, leading to 67% improvement of disease activity or related complications. This article also offers a comprehensive review of the diagnosis, management, and outcome of aortitis, supplementing the very limited literature on this disease.

A Dedicated Surveillance Program Improves Compliance with Endovascular Aortic Aneurysm Repair Follow-up.

BACKGROUND: Current recommendations suggest lifetime follow-up for endovascular aortic aneurysm repair (EVAR) patients to avoid consequences associated with endoleak and aneurysm enlargement. Follow-up compliance has been reported between 43% and 92%, with most single-center studies citing successful follow-up surveillance at less than 60%. We investigated follow-up completeness with a defined surveillance program and subsequent secondary intervention prevalence from a single center. METHODS: Our surveillance program notified patients of the need for follow-up imaging and surgeon review. Data were obtained from retrospective review of a prospective database, including operative and follow-up details, follow-up imaging completeness, endoleak incidence, and secondary intervention prevalence. RESULTS: Five hundred seventeen patients received elective EVAR from 2005 to 2015. Surveillance was achieved in 425 (82.3%). Mean number of follow-up studies was 4.2 ± 2.9 and median time to first follow-up was 36 days. Four hundred forty-eight patients (86.7%) had freedom from intervention. Sixty-nine unique patients (13.3%) had 107 secondary interventions. Median time to first secondary intervention in 69 patients was 476 days. Mean number of imaging studies for secondary intervention patients was 6.1 ± 3.9, compared with mean 3.4 ± 2.3 for patients without (P < 0.001). Overall mortality was 24.6% (n = 127), including 32 deaths of unknown cause (6.2% overall) and 95 of non-EVAR-related causes (18.3%). No aneurysm-related deaths were reported. CONCLUSIONS: Regular post-EVAR surveillance through a dedicated program resulted in a high rate of follow-up compliance, 13.3% rate of secondary intervention, and low aneurysm-related mortality. Careful lifetime surveillance remains important in long-term care following elective EVAR.

A prospective randomized comparison of contralateral snare versus retrograde gate cannulation in endovascular aneurysm repair.

OBJECTIVE: The objective of this study was to compare snare vs the standard retrograde gate cannulation method during endovascular aneurysm repair to determine the most efficient technique and to evaluate whether time was affected by graft design or the surgeon's experience. METHODS: This was a prospective randomized study involving single-center elective endovascular aneurysm repairs. Patients were randomized to the snare or retrograde group in a 1:1 ratio. The initial method was attempted for 15 minutes; if it was unsuccessful, the team switched to the alternative technique for an additional 15 minutes. The protocol continued until success was achieved. Data collected on demographic, anatomic, and procedural factors were analyzed for statistically significant differences. RESULTS: A total of 101 patients were included. Average age was 75.3 years, and 82% were male; 49 patients were randomized to snare and 52 to retrograde cannulation. The groups were overall similar. Median cannulation times were 3.9 minutes for the snare and 2.7 minutes for the retrograde technique (P = .13). The snare group attempts were successful within the initial 15-minute period in all but one patient (98% success). In the retrograde group, 5 of the 52 (10%) crossed over to snare. This difference did not reach statistical significance (P = .11). A difference was seen in the extremes of cannulation times. The surgeon's experience and graft design were not found to have significant effects on cannulation times. Further analysis of the retrograde group patients with long cannulation time found a relative breakpoint at the 5-minute mark. In those exceeding this time mark, the chance of eventual cannulation within 15 minutes dropped to 67%. In this group, median time to cannulation was 12.2 minutes for retrograde compared with 7.1 minutes for snare after crossover. CONCLUSIONS: Gate cannulation was successful using both methods with no statistical difference between the two in median time. Retrograde cannulation was found to be more likely to have short times. If cannulation by retrograde technique had not been achieved in the first 5 minutes, the chances of eventual success dropped significantly, and crossover to snare was more efficient. This finding suggests that one should consider an alternative method of gate cannulation if it has not been accomplished within this time.

Preoperative Inferior Mesenteric Artery Embolization: A Valid Method to Reduce the Rate of Type II Endoleak after EVAR?

BACKGROUND: Type II endoleak is the most commonly encountered endoleak after endovascular abdominal aortic aneurysm repair (EVAR). Some have advocated preoperative inferior mesenteric artery (IMA) embolization as a valid method for reducing the incidence of this endoleak, but controversies exist. We sought to demonstrate the impact of IMA embolization using a meta-analysis of currently available studies combined with our own experience. METHODS: We conducted an institutional review board-approved, retrospective analysis of all patients undergoing IMA embolization before EVAR between the years 2010 and 2015 and used as a control a similar group of patients with patent IMA. We divided patients from our own experience and 5 other studies into 2 groups: those who did not undergo IMA embolization (control) before EVAR and those who did. Rates of type II endoleaks, aneurysm sac regression, and secondary interventions were analyzed. RESULTS: A total of 620 patients from 6 studies were analyzed, including 258 patients who underwent an attempted IMA embolization before EVAR with a cumulative success rate of 99.2% (range, 93.8% to 100%). There was 1 fatality associated with IMA embolization. A meta-analysis showed that preoperative IMA embolization protected against type II endoleaks compared to the control group (odds ratio [OR], 0.31 [0.17-0.57]; P < 0.001, I2 = 43%). Furthermore, the rate of secondary intervention was significantly lower in the treatment group (OR, 0.12 [0.004-0.36]; P < 0.001, I2 = 0%). After IMA embolization, type II endoleak resulted from patent lumbar arteries in all 62 patients with persistent endoleak. CONCLUSIONS: Preoperative embolization of the IMA protects against the development of type II endoleaks and secondary interventions and may potentially lead to a rapid aneurysm sac regression. The procedure can be performed with a high technical success rate and minimal complications and should be considered in patients with IMA >3 mm before EVAR. A randomized trial, however, is required to clearly delineate the clinical significance of this technique.

Arterial Embolisms and Thrombosis in Upper Extremity Ischemia.

OBJECTIVE: Upper extremity ischemia (UEI) is an uncommon condition that can lead to permanent disability. There is a limited understanding of the etiology, management, and outcomes of the disease. METHODS: We retrospectively reviewed the charts of all patients who were diagnosed with "embolism and/or thrombosis of arteries of upper extremity" at our institution from January 2005 to December 2013. RESULTS: Patients diagnosed with embolisms were older (P < .001), more likely to undergo thromboembolectomy (P < .001), had higher rates of hypertension (P = .001), and had longer lengths of hospital stay (P = .002). There were no significant differences in complications or mortality at 30 days and up to 1 year. CONCLUSION: At our center, embolism was found to be the most common etiology for UEI followed by thrombosis and stenosis. Patients presented with embolism were older, were more likely to undergo thromboembolectomy, and had higher rates of hypertension and longer hospital stays.

Hyperbaric oxygen treatment outcome for different indications from a single center.

BACKGROUND: Hyperbaric oxygen (HBO) is used as an adjunctive therapy for a variety of indications. However, there is a lack of high-quality research evaluating HBO treatment outcomes for different indications available in the current literature. METHODS: We retrospectively reviewed all patients who underwent HBO therapy at a single hyperbaric center from January 2010 to December 2013 using predetermined criteria to analyze successful, improved, or failed treatment outcomes for the following indications: chronic refractory osteomyelitis, diabetic foot ulcer, failed flap or skin graft, osteoradionecrosis, soft tissue radiation necrosis, and multiple coexisting indications. RESULTS: Among the included 181 patients treated with adjunctive HBO at our center, 81.8% had either successful or improved treatment outcomes. A successful or improved outcome was observed in 82.6% of patients treated for chronic refractory osteomyelitis (n = 23), 74.1% for diabetic foot ulcer (n = 27), 75.7% for failed flap or skin graft (n = 33), 95.7% for osteoradionecrosis (n = 23), 88.1% for soft tissue radiation necrosis (n = 42), and 72.4% for multiple coexisting indications (n = 29). Among 4 patients treated for other indications, 100% of the cases were either successful or improved. CONCLUSIONS: This study has provided a comprehensive outcome survey of using HBO for the previously mentioned indications at our center. It supplements the literature with more evidence to support the consideration of HBO in different indications.

An analysis of variables affecting aortic neck length with implications for fenestrated endovascular repair of abdominal aortic aneurysm.

BACKGROUND: A major factor in the selection of patients for endovascular aneurysm repair (EVAR) is the character of the aortic neck, and studies suggest that many patients are treated outside of the instructions for use (IFU) criteria. By analyzing aortic neck morphology, we hope to identify factors that may influence decision making about the use of fenestrated endografts as an alternative to extending the neck limitations of traditional endografts. METHODS: A retrospective analysis was completed on 111 patients who underwent computed tomography angiography (CTA) scans between May 1, 2009 and January 3, 2011 for the evaluation of abdominal aortic aneurysm (AAA). Individual characteristics of neck and aneurysm morphology were analyzed to establish whether certain factors determined suitability for EVAR with traditional nonfenestrated endografts. In considering augmented neck lengths (ANL), anatomic measurements of distance from the start of aortic dilatation to the lowest renal artery (LRA) and highest renal artery (HRA) were analyzed. Measurements were analyzed using Stata software (version 11.2; StataCorp, College Station, TX). RESULTS: There were 86 men and 25 women in the patient population, with an average age of 72.9 years. In 46 patients, the proximal neck length was <15 mm, with 26 patients having neck lengths <10 mm. There was a negative relationship between AAA maximum diameter and proximal neck length (rs = -0.2237; P = 0.018), indicating that as aneurysm size increases, proximal neck length decreases. There was a significant correlation between proximal neck length and proximal neck diameter (rs = -0.2585; P = 0.006) and between proximal neck length and angle (rs = -0.2355; P = 0.013), and between proximal neck diameter and right iliac maximum diameter (rs = 0.2329; P = 0.014). Using fenestration to place an endograft above the LRA would create an ANL of >15 mm in 20 of 40 patients with aortic necks deemed too short to be eligible for EVAR using conventional infrarenal graft positioning. Extending the graft above the HRA would create an ANL of >15 mm in 36 of 40 patients. DISCUSSION: In this study, 41% of patients presented with neck lengths outside that of the traditional IFU for most aortic endografts. While there was wide variation from patient to patient, there was a general correlation between increasing AAA size and aneurysms that have shorter, wider, and more angulated proximal necks. Fenestration of even 1 renal artery could substantially increase the ANL. Additional study is warranted to determine if an increase in ANL in patients with otherwise short necks will positively impact long-term EVAR outcomes.

Fibrinogen level as a surrogate for the outcome of thrombolytic therapy using tissue plasminogen activator for acute lower extremity intravascular thrombosis.

PURPOSE: Monitoring of fibrinogen level is used to predict bleeding during lower extremity tissue plasminogen activator (tPA) infusions for peripheral arterial or venous thrombolysis. This practice is not fully addressed in the literature. MATERIALS AND METHODS: We retrospectively reviewed fibrinogen levels and studied bleeding rate from charts of patients who underwent lower extremity tPA infusions at a single hospital from January 2010 to May 2012. RESULTS: The rate of thrombolytic success did not correlate with fibrinogen level (P = .53). The rate of major bleeding was significantly higher for patients with a fibrinogen level at or below 150 mg/dL (P = .01). Patients whose tPA infusion was terminated within 46 hours had significantly lower rates of major bleeding (P = .01) and thrombolytic failure (P < .01). Periprocedural systolic blood pressure above 160 mm Hg was a risk factor for major bleeding (P = .02). There was no association between concomitant aspirin use (P = .90, .51) or hourly tPA dose (P = .71, .62) and thrombolytic success or major bleeding, respectively. CONCLUSION: Fibrinogen level ≤ 150 mg/dL is associated with increased risk of major bleeding during tPA infusions. We suggest serial fibrinogen measurement as a viable method to monitor bleeding risk during lower extremity tPA infusions.

Anatomy of the percutaneous presacral space for a novel fusion technique.

OBJECTIVES: Lumbar fusion has been widely used to treat unstable spinal disorders. Methods are evolving from open procedures to less invasive methods to avoid soft tissue trauma. Recently, a soft tissue sparing method to access the axial lumbosacral spine has been developed. It is crucial to determine structures potentially at risk for injury during this fusion technique. The anatomy of the presacral space and safety of the paracoccygeal approach were evaluated through cadaveric dissection and radiographic studies. The objective was to evaluate the safety of a paracoccygeal approach to the axial lumbosacral spine and determine structures that could potentially be injured. METHODS: The paracoccygeal approach was performed on two cadavers, followed by dissection. Distances from the midline trajectory of the approach to surrounding vascular structures were determined. Similar distances were also measured on computed tomography (CT) and magnetic resonance imaging (MRI) of 12 patients, as well as CT images of two additional patients. A "safe zone" was determined using the sagittal length of the presacral space and the distance between the most medial internal iliac vessel on the right and left, respectively. RESULTS: The coronal safe zone averaged 6.9 and 6.0 cm on MRI and CT, respectively. The mean distance from the anterior sacral margin to the rectum at the S3-S4 level was 1.2 and 1.3 cm on MRI and CT, respectively. CONCLUSION: In this study, we defined the "coronal safe zone" within the presacral space. This "safe zone" may guide surgeons when utilizing the percutaneous paracoccygeal approach.

Novel lumbosacral axial fixation techniques.

For patients with low back pain secondary to pathological motion of an unstable lumbar motion segment, interbody fusion may be indicated. Numerous open and minimally invasive techniques have been traditionally used, but all suffer from shortcomings related to biomechanics or inherent iatrogenic destabilization. A novel transaxial approach to the lumbosacral junction has recently been described which appears to obviate many of the limitations of previous techniques. Preliminary results of the transaxial approach to lumbosacral fixation appear promising.

Biomechanical evaluation of a novel lumbosacral axial fixation device.

BACKGROUND: Interbody arthrodesis is employed in the lumbar spine to eliminate painful motion and achieve stability through bony fusion. Bone grafts, metal cages, composite spacers, and growth factors are available and can be placed through traditional open techniques or minimally invasively. Whether placed anteriorly, posteriorly, or laterally, insertion of these implants necessitates compromise of the anulus--an inherently destabilizing procedure. A new axial percutaneous approach to the lumbosacral spine has been described. Using this technique, vertical access to the lumbosacral spine is achieved percutaneously via the presacral space. An implant that can be placed across a motion segment without compromise to the anulus avoids surgical destabilization and may be advantageous for interbody arthrodesis. The purpose of this study was to evaluate the in vitro biomechanical performance of the axial fixation rod, an anulus sparing, centrally placed interbody fusion implant for motion segment stabilization. METHOD OF APPROACH: Twenty-four bovine lumbar motion segments were mechanically tested using an unconstrainedflexibility protocol in sagittal and lateral bending, and torsion. Motion segments were also tested in axial compression. Each specimen was tested in an intact state, then drilled (simulating a transaxial approach to the lumbosacral spine), then with one of two axial fixation rods placed in the spine for stabilization. The range of motion, bending stiffness, and axial compressive stiffness were determined for each test condition. Results were compared to those previously reported for femoral ring allografts, bone dowels, BAK and BAK Proximity cages, Ray TFC, Brantigan ALIF and TLIF implants, the InFix Device, Danek TIBFD, single and double Harms cages, and Kaneda, Isola, and University plating systems. RESULTS: While axial drilling of specimens had little effect on stiffness and range of motion, specimens implanted with the axial fixation rod exhibited significant increases in stiffness and decreases in range of motion relative to intact state. When compared to existing anterior, posterior, and interbody instrumentation, lateral and sagittal bending stiffness of the axial fixation rod exceeded that of all other interbody devices, while stiffness in extension and axial compression were comparable to plate and rod constructs. Torsional stiffness was comparable to other interbody constructs and slightly lower than plate and rod constructs. CONCLUSIONS: For stabilization of the L5-S1 motion segment, axial placement of implants offers potential benefits relative to traditional exposures. The preliminary biomechanical data from this study indicate that the axial fixation rod compares favorably to other devices and may be suitable to reduce pathologic motion at L5-S1, thus promoting bony fusion.

New percutaneous access method for minimally invasive anterior lumbosacral surgery.

Preliminary cadaver, animal, and human studies were performed to determine the feasibility of axial anterior lumbosacral spine access using a percutaneous, presacral approach. Custom instruments were directed under fluoroscopic guidance along the midline of the anterior sacrum to the surface of the sacral promontory where an axial bore was created into the lower lumbar vertebral bodies and discs. Imaging and gross dissection were performed in cadavers and animals. The procedure was used for lumbosacral biopsy in human subjects guided by intraoperative imaging and clinical monitoring. All procedures were technically successful. This study demonstrates the feasibility of the axial access technique to the anterior lower lumbar spine.