Evolution of type II endoleaks based on different ultrasound-identified patterns.

OBJECTIVE: The objective of this study was to delineate the specific types of waveforms that exist in type II endoleaks (T2ELs) and their effect on aneurysm sac size. METHODS: Patients who underwent an endovascular aneurysm repair and were diagnosed with a T2EL were included in the study. The flow velocity characteristics of the T2ELs were evaluated in detail with duplex ultrasound. Four different flow patterns were identified: high resistance, low flow; low resistance, low flow; low resistance, high flow; and to-fro flow. The type and number of vessels involved, time at detection, evolution, and need for treatment were recorded. The aneurysm sac diameter was monitored with duplex ultrasound. A computed tomography scan was always performed at baseline within 1 month of the procedure and repeated only when symptoms developed or there were changes in the ultrasound examination findings, such as sac enlargement. RESULTS: Of 382 patients who underwent endovascular aneurysm repair in our institution, 56 (14.65%) were found to have a T2EL. There were 52 male and four female patients with a mean age of 74 years (61-86 years). The T2EL was diagnosed within the first month in 32 patients; 9 patients were diagnosed at 3 months, 5 patients at 6 months, 3 patients at 9 months, and 7 patients at 1 year or later. There were 43 patients who had a T2EL involving one vessel; two vessels were involved in 11 patients and three vessels were involved in two patients. During follow-up, several changes were observed for the different types of T2EL. High-resistance, low-flow endoleak was detected in 14 patients; of those, 13 were occluded and 1 converted to high flow. Low-resistance, low-flow endoleak was detected in seven patients; of those, 5 were occluded, 1 remained stable, and 1 converted to high flow with sac enlargement requiring treatment. Low-resistance, high-flow endoleak was found in 13 patients; of those, 8 were occluded, 3 remained stable, and 2 had sac enlargement requiring treatment; 1 patient presented with rupture. Finally, to-fro flow was identified in the majority of the patients (22); of those, 14 occluded, 3 remained stable, and 5 had sac enlargement requiring treatment; 2 patients presented with rupture. No deaths due to T2EL were encountered. CONCLUSIONS: Most of the T2ELs resulted in spontaneous occlusion and were not associated with sac enlargement. A low-resistance, high-flow or to-fro flow T2EL has higher chances of sac enlargement, rupture, and requiring reintervention.

Clinical characteristics and outcome of isolated infrarenal aortic stenosis in young patients.

OBJECTIVE: The objective of this study was to identify young patients with isolated infrarenal aortic atherosclerotic stenosis and to determine the clinical characteristics and midterm results of angioplasty and stenting. METHODS: Data from patients younger than 50 years with significant infrarenal aortic stenosis and at least 1 year of follow-up were prospectively collected. Patients with coexistent suprarenal or iliofemoral disease and Takayasu arteritis were excluded. All patients were treated with percutaneous transluminal angioplasty (PTA), primary stenting, or both. Pressure gradient was measured intraoperatively before and after the intervention. Every patient was monitored postoperatively with clinical examination, ankle-brachial index, and duplex ultrasound during follow-up. RESULTS: There were 51 patients, of whom 34 were excluded. Seventeen patients ranging in age from 37 to 49 years (mean, 43.7 years) met the study criteria, and they were all female. Fifteen patients had both history of hyperlipidemia and smoking with a mean of 53.2 pack-years. Fourteen patients were claudicants, whereas seven patients presented with distal embolization. Six patients were treated with primary stenting; four had PTA plus stent and seven had PTA alone. The length of the stenotic segments treated was <2 cm in 7, between 2 and 4 cm in 8, and >4 cm in 2. The mean follow-up for this cohort was 4.2 years. Mean pressure gradient before intervention was 49.06 ± 12.75 mm Hg, decreasing to 6.13 ± 2.06 mm Hg after intervention with a mean reduction of 42.75 ± 11.59 mm Hg. Mean ankle-brachial indices before the intervention were 0.67 ± 0.07, increasing to a mean of 0.92 ± 0.06 after the procedure. Stenosis developed in three patients during follow-up, requiring reintervention for a primary assisted patency of 100%. CONCLUSIONS: Isolated infrarenal aortic stenosis in young patients is primarily a disease of women. Most of these patients are heavy smokers with hyperlipidemia. PTA alone or with stenting has favorable midterm results.

Early and Late Endograft Limb Proximal Migration with Resulting Type 1b Endoleak following an EVAR for Ruptured AAA.

Introduction. Seal zone failure after EVAR leads to type 1 endoleaks and increases the risk of delayed aortic rupture. Type 1b endoleaks, although rare, represent a true risk to the repair. Case Presentation. We report the case of a 65-year-old female who underwent emergent endovascular repair for a ruptured infrarenal abdominal aortic aneurysm and developed bilateral type 1b endoleaks following proximal migration of both endograft limbs. The right-side failure was diagnosed within 48 hours from the initial repair and the left side at the 1-year follow-up. Both sides were successfully treated with endovascular techniques. A review of the literature with an analysis of potential risk factors is also reported. Conclusion. For patients undergoing EVAR for ruptured AAA and with noncalcified iliac arteries, more aggressive oversizing of the iliac limbs is recommended to prevents distal seal zone failures.

Predictors of early aortic neck dilatation after endovascular aneurysm repair with EndoAnchors.

OBJECTIVE: Dilatation of the aorta within the proximal neck after endovascular aneurysm repair (EVAR) can be associated with late endoleaks and migration. This study was designed to identify predictors of early neck dilation in patients undergoing EVAR with Heli-FX EndoAnchors (Medtronic, Santa Rosa, Calif) measured perioperatively to 1 year at different longitudinal levels of neck length. METHODS: The study group of Aneurysm Treatment Using the Heli-FX Aortic Securement System (ANCHOR) comprises 257 consecutive patients prospectively enrolled between April 2012 and September 2014 undergoing EVAR with Heli-FX EndoAnchor implantation at 38 investigational sites. Only patients undergoing EndoAnchor implantation at the time of the initial EVAR were included (primary treatment arm). Aortic diameter was measured at the suprarenal level and at three levels within the proximal neck. Neck dilatation was assessed in 209 patients with adequate computed tomography imaging at baseline and 1 month and in 62 patients at 1 month and 1 year (mean, 11.9 ± 4.0 months). Multivariable analyses were performed to identify independent predictors of perioperative (baseline to 1 month) and early postoperative (1 month to 1 year) aortic dilation at each level; analyses included 6 candidate variables, 6 clinical, and 14 anatomic run in eight models (one at each of the four aortic levels for both time frames). RESULTS: The mean aortic neck dilation at 1 month was 0.2 ± 1.7 mm, 0.7 ± 2.2 mm, and 0.9 ± 3.6 mm at 0 mm, 5 mm, and 10 mm below the lowest renal artery, and 0.0 ± 1.5 mm at the suprarenal level. From 1 month to 1 year, neck dilatation was 0.5 ± 1.6 mm, 0.4 ± 1.5 mm, 0.2 ± 1.8 mm, and -0.3 ± 1.1 mm at the same four levels, respectively. Dilatation of ≥3 mm at level 5 mm distal to the lowest renal artery was observed in 26 patients (12.5%) from preoperative to 1 month and in 5 patients (8.1%) between 1 month and 1 year. Multivariable regression identified several variables predictive of perioperative (preoperative to 1 month) neck dilatation: baseline neck diameter, mural calcium (protective), and endografts with a suprarenal stent. Neck dilatation between 1 month and 1 year was associated with baseline neck diameter, neck length (protective), neck angulation, device oversizing, number of EndoAnchors implanted (protective), and endografts with a suprarenal stent. CONCLUSIONS: Aortic diameter and graft oversizing appear to be independent risk factors for early aortic neck dilatation. EndoAnchors have a protective effect on neck dilatation at their usual level of deployment.

The Use of AngioVac for Symptomatic Aortic Thrombus Complicated by Mesenteric Ischemia.

Aortic thrombus complicated by mesenteric ischemia is a rare but rather challenging entity. With the recent advancements of endovascular techniques, there is a trend to replace the traditional open surgery with an endovascular approach. We report a patient with paravisceral aortic thrombus involving the celiac artery and superior mesenteric artery (SMA). The patient was complaining of worsening abdominal pain, with clinical findings of leukocytosis, normal lactate, and diagnostic laparoscopy demonstrating a segment of threatened jejunum. We describe the novel use of vacuum-assisted suction filtration device in combination with over-the-wire thrombectomy and stenting to successfully restore blood flow within the SMA. The patient had resolution of her symptoms with improved blood flow to the bowel and no need for resection.

Radiation exposure in endovascular repair of abdominal and thoracic aortic aneurysms.

BACKGROUND: Endovascular aortic repair has become increasingly popular the last years for the treatment of abdominal aortic aneurysms (EVAR) and thoracic aortic aneurysms. EVAR is less invasive compared with the classic open approach, related to a decreased immediate postoperative morbidity and mortality. Those beneficial characteristics of EVAR do not come without a cost, since EVAR requires that the patient will be exposed to a significant amount of radiation during preoperative planning, graft placement, and consecutive follow-up. This systematic review examines the periprocedural radiation exposure to patients and staff as well as ways to ameliorate it. METHODS: A systematic literature search was conducted using the MEDLINE electronic database. All articles reporting radiation exposure to alive humans during EVAR were eligible for review. Only studies publishing numerical data regarding radiation exposure were included in the Results section. Other relevant articles were used for further discussion. RESULTS: Twenty-four studies, both prospective and retrospective in nature, were included. These studies revealed that the radiation exposure depends on the specific type of procedure, with more complex procedures carrying greater radiation burden. Variations in the positioning and operating of the fluoroscopic unit may significantly alter radiation dose to both patients and staff. There was an apparent lack of education among vascular specialists and trainees in terms of radiation safety awareness. At follow-up, a significant number of patients needed additional procedures, and all required radiographic imaging, further increasing the radiation exposure to alarming levels. CONCLUSIONS: Every effort should be made to decrease radiation exposure related to endovascular aortic procedures. Attempts must be directed towards maximizing the operator's awareness, welcoming new imaging technology emitting less radiation, and shifting to follow-up strategies that require minimal or no radiation.