Jan Macierewicz

Endovascular AAA repair: prevention of side branch endoleaks with thrombogenic sponge.

Purpose: To report a technique that might decrease the incidence of lumbar artery endoleaks following endovascular repair (EVR) of abdominal aortic aneurysms (AAAs). Methods: Ninety-three patients (86 males, median age 72 years, range 56 to 88) undergoing EVR with the aortomonoiliac technique were entered into a study to detect and then occlude patent side branches before completion of the endografting procedure. Prior to deploying the iliac occluder, an aneurysmogram was performed to detect patent aortic side branches. If these side branches were found, an absorbable gelatin sponge was inserted into the aneurysm sac via the occluder introducer sheath. The patients were followed with contrast-enhanced spiral computed tomography (CT) at 1 week and 3, 6, and 12 months to detect the presence of endoleaks. Results: Forty-eight (52%) patients demonstrated patent side branches that were occluded by the insertion of gelatin sponges into the aneurysm sac. The remaining 45 patients without evidence of side branch flow were untreated. Ten (10.7%) patients died in the perioperative period, and 15 (16.1%) primary endoleaks (13 proximal, 2 distal) were detected. This left 68 (73.1%) patients for follow-up, 33 (48.5%) of whom had patent branch vessels treated with the thrombogenic sponge. The median follow-up was 4 months (range 1 to 17), during which time no side branch endoleak was detected on surveillance CT scans in any of the 68 patients, which included all patients treated with the thrombogenic sponge technique and those in whom no patent side branches had been identified. Conclusions: We have demonstrated a safe and reliable method of preventing lumbar artery endoleaks following endovascular AAA repair.

Sigmoid Ischemia and the Inflammatory Response following Endovascular Abdominal Aortic Aneurysm Repair

Purpose: To assess the relationship between sigmoid colonic perfusion, endotoxemia, and cytokine generation in patients undergoing elective open repair (OR) or endovascular repair (EVR) of infrarenal abdominal aortic aneurysms (AAA). Methods: Ten patients (9 males; average age 67.6 ± 2.5 years, mean aneurysm diameter 6.9 ± 0.6 cm) undergoing OR were compared to 10 patients (all males; average age 70.3 ± 2.6 years, mean aneurysm diameter 6.5 ± 0.5 cm) whose repair was performed using the EVR technique. The partial pressure of the carbon dioxide gap (Pco2gap = tissue Pco2 — arterial Pco2) of the sigmoid colonic mucosa was measured using a silicone tonometer to evaluate bowel perfusion. Blood samples were collected into pyrogen-free heparinized tubes for quantification of plasma concentrations of endotoxin, tumor necrosis factor alpha (TNF-α), and interleukin 6 (IL-6) before, during, and after aortic repair. Results: Patients in the OR group had a significantly greater increase in Pco2gap, suggesting a greater degree of bowel ischemia compared to the EVR group. This was associated with significantly greater postoperative concentrations of endotoxin, TNF-α, and IL-6 in the OR group. A significant correlation was found between Pco2gap, IL-6, and postoperative core temperature. Conclusions: The results suggest that the degree of bowel ischemia, endotoxemia, and cytokine generation following elective infrarenal AAA reconstruction may be reduced if the endovascular technique is used instead of conventional surgery.

Mortality Rates following Endovascular Repair of Abdominal Aortic Aneurysms

Purpose: To present the perioperative and late mortality following endovascular repair (EVR) of abdominal aortic aneurysms (AAAs). Methods: Data were collected prospectively on 221 patients undergoing AAA EVR over a 4-year period (median 5-month follow-up). Patients were classified preoperatively as high risk with at least 1 of these features: serum creatinine > 150 μmol/L, ischemic heart disease or poor left ventricular function, respiratory function < 50% of predicted normal, ruptured or symptomatic AAA, contraindication to or failed open repair, and age > 80 years. Results: One hundred forty (63.3%) patients were classified as high risk, the most common criterion being cardiac disease (n = 96, 68.6%). There were 25 (11.3%) deaths in the 30-day perioperative period, 22 (15.7%) in the high-risk group compared to 3 (3.7%) in the acceptable-risk group (p = 0.02). The most common causes of perioperative death were multisystem organ failure and myocardial infarction. A further 21 (9.5%) late deaths occurred, 16 (11.4%) in the high-risk group and 5 (6.2%) in the acceptable-risk group (p > 0.1). Conclusions: The mortality of patients at acceptable risk undergoing EVR compares with the best published series for conventional open AAA repair. The perioperative and late mortality in the high-risk patients are substantially higher.

Aorfix stent graft for abdominal aortic aneurysms reduces the risk of proximal type 1 endoleak in angulated necks : Bench-test study

Neck angulation (NA) is an important risk factor for type 1 proximal endoleaks following stenting of abdominal aortic aneurysms. The Aorfix (Lombard Medical, Oxon, UK) is a new flexible stent graft designed to overcome this issue. The aim of this study was to compare the endoleak flow rate (EFR) in relation to NA between the Aorfix and other manufactured stent grafts. A flow model with silicone proximal and distal necks was used. EFRs corresponding to 10 neck angles between 0 and 70° were measured. Eight stent grafts were tested: Aorfix, Ancure (Guidant, Indianapolis, IN), Powerlink (Endologix, Irvine, CA), AneuRx (Medtronic, Sunnyvale, CA), Excluder (W.L. Gore & Associates, Flagstaff, AZ), Zenith and Zenith-Flex (Cook Inc., Bloomington, IN), and Lifepath (Edwards Lifesciences, Irvine, CA). For all stent grafts except the Aorfix, the EFR was greater than at baseline for NA ≥ 30° (p < .01). The EFR at NA ≥ 30° was lower with the Aorfix compared with the other stent grafts (p < .01). NA had no influence on the EFR with the Aorfix. The Aorfix may decrease the incidence of proximal type 1 endoleak in patients with a severely angulated aortic neck.

Endovascular Repair of Perisplanchnic Abdominal Aortic Aneurysm with Visceral Vessel Transposition

Purpose: To report a combined endoluminal and open surgical approach for a suprarenal abdominal aortic aneurysm (AAA) with coexistent splanchnic vessel stenoses. Methods and Results: A 64-year-old man presented with an aneurysm of the proximal abdominal aorta and severe stenoses of the celiac axis and superior mesenteric artery (SMA). An initial 2-stage plan to stent the visceral vessel stenoses and exclude the aneurysm with a fenestrated stent-graft failed when the celiac lesion could not be crossed. The approach was changed to restore visceral perfusion with a bifurcated left iliosplenic and ilio-SMA bypass graft. Exclusion of the aneurysm was achieved with a custom-made suprarenal aortic tube stent-graft (Ivancev-Malmö) system. The patient is free of symptoms at 22 months, and there was no aneurysm visible on the 14-month CT scan. Conclusions: Hybrid techniques are an alternative treatment for complex perivisceral aortic aneurysms when total endovascular reconstruction is not possible.