Marcel A. Goodman

Fenestration in Endovascular Grafts for Aortic Aneurysm Repair: New Horizons for Preserving Blood Flow in Branch Vessels

PURPOSE To describe techniques for deploying fenestrated stent-grafts that use partial graft deployment and guided tracking of the fenestration to the arterial orifice. TECHNIQUE Fenestrations have been added to custom-made tube grafts and commercially manufactured Zenith stent-graft systems to preserve perfusion of aortic side branches. Partial device deployment, orientation markers on the endograft, and intraoperative angiography enable maneuvering of the fenestration over the orifice of the target vessel with the aid of guiding catheters. Placement of a Palmaz stent overlapping the fenestration and vessel orifice secures the junction. Two variations of fenestration have preserved blood flow in renal arteries during endovascular repair of abdominal aortic aneurysms (AAAs); similar techniques have maintained flow to the celiac axis in a thoracic aortic aneurysm. CONCLUSIONS Accurate placement of a fenestration over the orifice of a target vessel is feasible, but long-term maintenance of position is dependent on secure graft fixation. This capability brings us a step closer to overcoming the problem of inadequate necks in infra-renal AAAs, especially when the neck is foreshortened by asymmetry of the renal origins. It may also pave the way for the eventual replacement of the entire aorta with an endoluminal graft.

Comparison of Transperitoneal and Retroperitoneal Approaches for Infrarenal Aortic Surgery: Early and Late Results

The retroperitoneal approach to the infrarenal aorta was purported to have a shorter recovery and reduced degree of surgical stress than the transperitoneal approach. Hence, this study aimed to determine any advantages of one approach over the other. One hundred patients undergoing infrarenal aortic surgery between 1989 and 1992 were randomized to the transperitoneal or retroperitoneal approach; 64 operations were for aneurysms (32 transperitoneal, 32 retroperitoneal) and 36 for occlusive disease (18 transperitoneal, 18 retroperitoneal). Parameters monitored were operating time, cross-clamp time, blood loss, fluid requirement in first 24 h, analgesia requirements, gastrointestinal function, morbidity, mortality and length of stay in intensive care and hospital. A minimum 3-year follow-up was obtained to assess mortality and wound problems. Inter-group demographic data were comparable. There was no significant difference between the two approaches for: operating time 190 versus 202 min, P = 0.26); cross-clamp time (72 versus 81 min, P = 0.93); blood loss (1095 versus 1072 ml, P = 0.56); 24-hour fluid requirements (6900 versus 7000 ml, P = 0.45); analgesia requirements (60 versus 55 mg, P = 0.37), gastrointestinal function, morbidity (P = 0.75), mortality, and length of stay in intensive care (2 versus 2 days, P = 0.80) and hospital (10.5 versus 10 days, P = 0.76). In the long term there were significantly more wound problems (bulging, hernias and wound pain) in the retroperitoneal group. Long-term mortality was similar in both groups.

The Perth HLB Bifurcated Endoluminal Graft: A Review of the Experience and Intermediate Results

Endoluminal grafting for abdominal aortic aneurysm based upon Dacron-coated Z stents was commenced in March 1993. A modular system for treatment of infrarenal aorto-iliac aneurysmal disease was developed in 1994. The experimental model, method of delivery, graft construction and initial results were reported. Since 1994, 108 bifurcated HLB (Perth) endografts for infrarenal aorto-iliac aneurysmal disease have been implemented. Initial technical success in deployment and exclusion of the aneurysm was achieved in 94 (87%) cases. Secondary endovascular procedures were performed in six cases and were successful in excluding the aneurysm. Ninety patients are alive currently. Twelve have died of co-morbid conditions. Six have died of aneurysmal disease, either from rupture or the result of treatment attempts. Fifteen early endoleaks (within 30 days) have been detected with three persisting. Four have sealed without further intervention, six after the secondary procedure and two patients have died. Conversion to open aneurysmal repair has been performed in five cases: three early and two late. Two of the early group but none of the late intervention group died. No graft infections have been detected to date. With increasing experience criteria for patient selection for endoluminal grafting and the type of graft to be inserted, have been developed. These criteria, lessons learnt and technical points of importance are discussed.

Successful embolization of persistent endoleak from a patent inferior mesenteric artery.

PURPOSE To report the successful endovascular occlusion of a persistent endoleak owing to collateral perfusion in a 1-year-old bifurcated aortic endograft. METHODS AND RESULTS An 81-year-old man underwent endovascular repair of a 5.5-cm abdominal aortic aneurysm (AAA) with a bifurcated stent-graft in 1995; collateral perfusion of the excluded aneurysm by retrograde filling of the patent inferior mesenteric artery (IMA) was noted postoperatively. At his 1-year follow-up, the mid-sac endoleak persisted on contrast-enhanced computed tomography. Using the superior mesenteric artery for access, the stump of the IMA was successfully embolized with glue. CONCLUSIONS This case, which highlights the importance of documenting a patent IMA prior to AAA endografting, illustrates one option for the management of persistent collateral perfusion of endovascularly excluded aneurysms.

Hybrid Open-Endoluminal Technique for Repair of Thoracoabdominal Aneurysm Involving the Celiac Axis

PURPOSE To describe a technique combining endoluminal and open approaches for the repair of thoracoabdominal aneurysms involving the celiac axis. CASE REPORT Two patients with type I thoracoabdominal aneurysm and suboptimal cardiac reserve underwent transluminal stent-graft implantation. To achieve satisfactory distal seal, the caudal end of the endograft was circumscribed with a Dacron band that was sutured to the aorta and endograft through a midline incision. The patent celiac artery in both patients was ligated to stop retrograde filling of the aneurysm sac. The patients developed no problems perioperatively, and exclusion of the aneurysms was confirmed by follow-up imaging. Three years after endografting, both patients had excluded aneurysms without evidence of endoleak or device migration. CONCLUSIONS This combined approach is another treatment option for thoracic aneurysms that have an anatomically suitable proximal attachment zone with a compromised distal neck.

Duration of antimicrobial prophylaxis in vascular surgery

BACKGROUND This randomized clinical trial compares the incidence of wound infection after vascular surgery in patients who received prophylaxis using the same antibiotic as either a single-dose or a multiple-dose regimen (until the lines/drain tubes were removed, but not for more than 5 days). METHODS Each of the 302 patients who entered the study received ticarcillin 3.0 g/clavulanate 0.1 g (Timentin) intravenously immediately after the induction of anesthesia. Patients randomized to the multiple-dose group received an average of 14.3 doses (range 9 to 20). RESULTS The incidence of wound infections was 18% (28 of 153) for patients in the single-dose group and 10% (15 of 149) for patients in the multiple-dose group (P = 0.04; relative risk estimate = 2.00, 95% confidence interval = -1.02 to 3.92). CONCLUSIONS A multiple-dose antibiotic regimen, rather than single-dose therapy, provides optimal prophylaxis against wound infection for patients undergoing vascular surgery.

Treatment of Infrarenal Abdominal Aortic Aneurysms with Oversized (36-mm) Zenith Endografts

Purpose: To evaluate the outcome of treating infrarenal abdominal aortic aneurysms with unfavorable necks using the 36-mm Zenith endograft. Methods: The indication for use of the 36-mm endograft for infrarenal aortic aneurysm was a minimum 20-mm-long sealing zone and a diameter >28 mm at any point but <34 mm, varying more than 3 mm in contour. A series of 67 patients (64 men; mean age 76.2 years, range 59.5 to 88.3) who had been treated with the 36-mm endografts between June 1999 and February 2004 were assessed for medium-term outcomes. The patients were identified from the device planning records. Follow-up was carried out using chart review and direct patient contact. The indication for use of the endograft was checked with the aneurysm neck profile from the original planning diagrams. Cause of death was ascertained from the treating clinician, the medical record, or the State Death Registry. Outcome endpoints were proximal type I and type III endoleaks, migration, sac size change, and death. Results: The mean diameter of the sealing zone was 31.9±1.6 mm within the 20-mm segment from the lowest renal artery. Stent-graft delivery was achieved in all 67 patients. Two (3%) patients died within 30 days from non-graft-related cardiorespiratory causes. Proximal type I endoleaks were identified in 3 (4.5%) patients: 2 during deployment and another at 9 days. The mean follow-up period for the 65 patients who survived 30 days was 26.9±12.6 months (range 2–66). Migration occurred in 1 patient with development of a type III endoleak and sac reperfusion due to separation of the graft body from the bare anchor stent owing to suture breakage. Forty-seven patients were alive at the last review. The aneurysm sac had contracted or was unchanged in 45 (96%) cases. Minor enlargements of the sac were observed in 2 patients. The re-intervention rate was 16.4% (11 patients). There was 1 conversion to open repair to treat perigraft sepsis. The aneurysm- and procedure-related mortality was 4.5%; no patient experienced rupture. All-cause mortality was 29.9% (20/67). Conclusion: Large caliber endografts such as the Zenith 36-mm are an alternative option to open surgery or fenestrated endografting for some infrarenal aneurysms.

Endovascular Conversion Procedure for Failed Primary Endovascular Aortic Stent-Grafts

Initial failure of successful deployment of endovascular aortic stent-grafts can be due to a variety of factors and frequently requires surgical intervention. We describe an endovascular technique for salvaging initially failed tubular aortic and bifurcated aortoiliac stent-grafts with reference to three cases.

Lipolytic enzyme and phospholipid level changes in intraoperative salvaged blood.

Summary. Autotransfusion is becoming increasingly popular, mainly because it eliminates the risk of disease transmission. One of the techniques available is intra‐operative blood salvage and retransfusion with or without washing of the collected blood. The blood collected during this process is subjected to a variety of chemical and physical insults which can alter the normal composition of the plasma by activating plasma and cellular homeostatic mechanisms. In this study, we measured the plasma levels of total phospholipids, lysolecithin and non‐esterified fatty acids, and the lipolytic enzymes phospholipase A2 (PLA2) and lipase in the salvaged blood before and after washing. In the unwashed salvaged blood the mean levels of PLA2, non‐esterified fatty acids and lysophospholipids increased by 144, 96 and 149%, respectively, while those of total phospholipids and lipase did not change to any extent. All these substances were reduced to well below the patients circulating plasma levels by washing the collected blood. The changes indicate that the lipid profile of salvaged blood is significantly altered and that potentially dangerous substances such as PLA2and its metabolites, lysolecithin and non‐esterified fatty acids, are present in increased amounts. Washing the blood is recommended prior to reinfusion.