Noel, Audra A.

Background and Purpose —Hypercholesterolemia is associated with abnormal endothelium-dependent vasorelaxation due to decreased nitric oxide bioavailability. Our aim was to examine the effect of adenovirus-mediated gene transfer of endothelial nitric oxide synthase (eNOS) to the hypercholesterolemic rabbit carotid artery in vivo. In addition, we examined whether adenovirus-mediated gene transfer was associated with vascular dysfunction. Methods —Rabbits were fed a 1% cholesterol diet for 4 weeks followed by a 0.5% cholesterol diet for 6 weeks. Vascular reactivity was assessed in nontransduced carotid arteries from chow- and cholesterol-fed animals. In addition, carotid arteries were surgically isolated, and 2 separate doses of adenoviral vectors encoding eNOS or β-galactosidase (AdβGal) on the contralateral side were delivered to the lumen (1×10 10 and 5×10 10 pfu/mL). Results —Abnormal acetylcholine-mediated endothelium-dependent vasorelaxation was detected in the carotid artery from cholesterol-fed animals, whereas responses to calcium ionophore A23187 and diethylamine NONOate were normal. Vascular reactivity was similar in nontransduced and AdβGal-transduced hypercholesterolemic vessels. In vessels transduced with eNOS, transgene expression was demonstrated by immunostaining in both the endothelium and the adventitia and by Western blot analysis. High-dose but not low-dose eNOS gene transfer enhanced endothelium-dependent relaxation in vessels from cholesterol-fed rabbits. Conclusions —Adenovirus-mediated gene transfer of eNOS to carotid arteries of cholesterol-fed animals improves endothelium-dependent relaxation when an optimal viral titer is administered.

The coexistence of urologic malignancy (UM) and abdominal aortic aneurysm (AAA) is rare. Simultaneous treatment may increase morbidity, whereas staged operations delay necessary treatment. We reviewed our experience to develop guidelines for evaluation and management. Clinical data of all patients diagnosed between 1980 and 1998 with both AAA and UM, who also had staged or simultaneous surgical treatment were reviewed. Four thousand forty-seven patients underwent AAA repair during the study period at our institution. Of these, 18 (0.44%) patients, 16 men and two women (mean age: 74 years, range: 61 to 92) had UM. UM was discovered incidentally in nine patients with AAA with computed tomography (CT) scan (7) and ultrasonography (2). In one patient with AAA, hematuria raised the suspicion of UM. Eight patients were diagnosed with AAA during evaluation of UM by CT scan or ultrasound (7) or during laparotomy (1). Initial signs and symptoms included abdominal pain (33%), gross hematuria (33%), and urinary tract infections (17%), although 33% were asymptomatic. The AAA was symptomatic at first examination in three (17%) patients, 14 (78%) patients had hypertension, and two (11%) had renal insufficiency (overall mean serum creatinine: 1.6, range: 0.8 to 3.7). Mean AAA diameter was 5.8 cm (range: 3.8 to 8 cm). Aortography documented significant contralateral renal artery disease in two patients. Twelve patients underwent simultaneous AAA repair and resection of UM; the operations were staged in six (AAA repair first in 2, nephrectomy first in 4). One patient required emergent repair of a ruptured AAA three days after nephrectomy. UM was treated with nephrectomy in 17 patients, and with bilateral ureterectomy and cystectomy in one. A straight aortic graft was implanted in seven patients, a bifurcated graft in ten, and one had extra-anatomic reconstruction. Two patients required reconstruction of the contralateral renal artery. The 30-day mortality rate was 0% after staged and 6% after simultaneous repair (p= >0.1). Major perioperative complications occurred more frequently after simultaneous (42%) than after staged repair (33%), although the difference was not significant (p= >0.1). Two patients developed postoperative renal failure. Seventeen patients were followed for an average of 3.9 years (14 days to 10.8 years). Three (17%) patients died of recurrent cancer at 1, 10.7, and 10.8 years after surgery. Patients with resectable UM have satisfactory long-term survival, which justifies aggressive treatment of concomitant AAA. Aortography in these patients is suggested to exclude contralateral renal artery disease. Complications were frequent, but simultaneous repair did not increase morbidity or mortality significantly. The risk of AAA rupture after nephrectomy, need to correct contralateral renal artery disease at the time of nephrectomy, and disadvantage of delaying treatment of UM are compelling reasons to favor simultaneous treatment of AAA and UM.

Previous results following subfascial endoscopic perforator vein surgery were reported to be worse in post-thrombotic syndrome than in limbs with primary valvular incompetence. This report comprises a larger patient cohort with longer follow-up. The goal of this study was to determine if subfascial endoscopic perforator vein surgery is justified in patients with postthrombotic venous insufficiency. The clinical data of 91 consecutive patients who underwent subfascial endoscopic perforator vein surgery with or without superficial reflux ablation over a 7-year period from May 1993 to June 2000 were retrospectively analyzed. Fifty-four females and 37 males (median age, 53 years; range, 20-77) underwent 103 subfascial endoscopic perforator vein surgery procedures. Forty-two limbs were classified as C6 (active ulcer), 34 as C5 (healed ulcer), and 24 as C4 (lipodermatosclerosis). Thirty procedures were performed in post-thrombotic limbs. Concomitant superficial reflux ablation was performed in 74 limbs (72%); saphenous vein stripping had been previously performed in 29 (28%). Deep venous incompetence was present in 89% of limbs; 13% had venous outflow obstruction on plethysmography. Cumulative ulcer healing in post-thrombotic limbs was not significantly different from limbs with primary valvular incompetence; 30-, 60-, and 90-day healing rates were 44%, 72%, and 72% vs 39%, 70%, and 87%, respectively (p = 0.35). On univariate analysis, the presence of ulcer greater than 2 cm in diameter was associated with delayed ulcer healing (p = 0.02). Cumulative ulcer recurrence in all limbs was 4%, 20%, and 27% at 1, 3, and 5 years, respectively. Ulcer recurrence in post-thrombotic limbs was higher than in limbs with primary valvular incompetence at 1, 3, and 5 years; 16%, 47%, and 56% vs 0%, 8%, and 15%, respectively (p = 0.001). Recurrent ulcers were small, superficial, and easier to heal. Clinical improvement was significant even in post-thrombotic limbs; median clinical score decreased from 9.5 to 3 (p=0.001), and median outcome score was +2 (mean 1.9; range, -I to 3). Median clinical score in patients with primary valvular incompetence improved from 6 to 1.5 (p = 0.0001). Subfascial endoscopic perforator vein surgery with superficial reflux ablation promoted ulcer healing, improved clinical outcome, and resulted in a low long-term ulcer recurrence rate in limbs with primary valvular incompetence. Despite good clinical outcome in post-thrombotic limbs, ulcer recurrence was high. These results imply that the role of subfascial endoscopic perforator vein surgery with superficial reflux ablation in patients with post-thrombotic limbs continues to be controversial.

Strict morphologic criteria must be used for patient selection to achieve durable success with endovascular aortic aneurysm repair (EVAR). The goal of this study was to assess morphologic suitability (MS) of abdominal aortic aneurysms (AAAs) for 2 currently approved bifurcated stent grafts and identify reasons for exclusion from EVAR. The authors reviewed the electronic charts of 1,795 consecutive patients who were diagnosed as having AAA between January 1999 and July 2001 at their institution. Three hundred and twenty patients had an AAA with a diameter of =5.0 cm, measured on computed tomography (CT). The records of 301 patients, 254 men, 47 women, with a mean age of 74 years were available for review, and these patients constituted the study cohort. Criteria used for MS included a proximal neck length =15 mm; neck diameter between 18 and 26 mm; neck angulation =60°; common or external iliac artery (CIA or EIA) diameters of 7–16 mm and 8–13 mm, respectively, for AneuRx (Medtronic Ave, Santa Rosa, CA) and Ancure (Guidant Cardiac and Vascular Division, Menlo Park, CA) bifurcated grafts. AAAs were suitable for AneuRx device in 14% of patients (43 of 301; 95% CI = 11–19%) and for Ancure in 5% (16 of 301; 95% CI = 3.1–9%). The main reason for exclusion was an inadequate proximal aortic neck (73%). The neck was too short in 49.5%, too wide in 64% and badly angulated in 12% of the patients. Iliac artery morphology precluded EVAR with AneuRx and Ancure devices in 52% and 80%. Both CIAs were too wide for EVAR in 43% and 77%, respectively. When iliac artery diameter =20 mm was accepted, iliac suitability for AneuRx increased from 49% to 70% and overall suitability increased from 14% to 20%. When more permissive criteria were used for MS (neck length =10 mm, neck diameter =30 mm, CIA =20), 39% of patients became candidates for EVAR. More than three fourths of the patients with an AAA =5.0 cm in size, seen in a tertiary referral center, are morphologically not suitable for EVAR using 2 currently approved bifurcated endografts. The main reasons for exclusion are a short or wide proximal aortic neck. Considerable changes in size of the devices and in proximal attachment techniques have to occur before most AAAs will be suitable for EVAR.

Widespread applications of totally laparoscopic aortic reconstructions have been limited by the long cross-clamp time required to suture the aortic anastomosis despite improvement in instrumentation. The authors' hypothesis was that a “one-step anastomosis concept” using an intraluminal stapler would allow shorter cross-clamp time but similar patency and imperviousness as videoscopic suturing techniques. An intraluminal stapler (Endopath-ILS, Ethicon) with a modified anvil was used to perform videoscopic-assisted thoracic aorta-to-iliac artery bypass with a 21 mm by 8 mm polytetrafluoroethylene (PTFE) graft in 22 sheep through a minimally invasive approach using a 5 cm thoracotomy. The graft-to-iliac artery anastomoses were hand sutured through a flank incision. Twelve sheep were used to establish the technique and 10 subsequent animals constituted the study group. Aortic cross-clamp time, imperviousness, and need for additional sutures were recorded and compared to previously reported data using videoscopic suturing in pigs. Patency was assessed by comparing lower limb arterial pressures. Macroscopic and microscopic examinations of the anastomoses were performed at different time-points within the first 3 months. Videoscopic-assisted stapled anastomoses were also performed on atherosclerotic aortas of 3 human cadavers. Stapled anastomoses between the thoracic aorta and PTFE graft were completed in 8 of 10 animals. Two animals were euthanized after stapler failure and anastomotic bleeding. Sutures to strengthen the anastomosis had to be used in 4 cases. Mean aortic cross-clamp time in 8 successful cases was 4.3 ±2.9 minutes (range 2–11 minutes) and was significantly shorter than clamp time of videoscopic suturing technique (48.7 ±9.4 minutes, p<0.0001). Imperviousness was good or excellent in 4 animals and fair in 4 animals. All anastomoses were patent at the end of the procedure. Examination of the anastomosis of the 2 failed interventions showed medial aortic tear surrounding the anastomosis in 1 case and misfired staples in the other. No graft occlusion was noted during follow-up ranging from 0 to 12 weeks. At the time of harvest, no bleeding was noted after epinephrine and volume infusion to increase mean arterial pressure to 200 mm Hg for 15 minutes. Macroscopic examination of the anastomoses revealed adequate healing with circumferential stapling of the prosthesis to the aortic wall and no stenosis or thrombus except in 1 false aneurysm (1/7, 14%). Surface electron microscopy showed cells coverage of the anastomosis surface. When applied on human cadaver thoracic and abdominal aorta with atherosclerotic changes, clamping times of less than 5 minutes were achieved. However, imperviousness tested with saline was poor. An automatic stapling device allows performance of a graft-to-aorta anastomosis through a minimally invasive approach with shorter clamping time than a videoscopic suturing technique. However, the current technique of aortic stapling is unreliable and further improvements are needed.

Videoscopic surgical techniques have been developed to reduce morbidity of open aortic reconstructions. The advantage of hand-assisted laparoscopic surgery (HALS) technique is the introduction of the surgeon's hand into the peritoneal cavity. The aims of this study were to assess the feasibility and to examine the learning curve, limitations, and pitfalls of the HALS technique to perform aortic reconstruction in a porcine model for training purposes. HALS aorto-aortic 8 mm polytetrafluoroethylene (PTFE) interposition grafts were placed in 12 pigs. Proficiency was judged by measuring operative time points, satisfactory completion of the operation, and the need to convert to open procedure. The strength of the relationship between order number in which a procedure was performed and the various surgical time point measures was described with the Spearman rank correlation. HALS aortic grafting was successful in the last 8 pigs. The first 2 pigs required conversion to open repair, and the graft of the third and fourth animals occluded early. Median operative time was 115 minutes (range: 75 to 205), median intestinal retraction time was 28 minutes (range: 10 to 40), median aortoiliac dissection time was 30 minutes (range: 20 to 60), and median aortic cross-clamp time was 48 minutes (range: 35 to 82). The Spearman rank correlations and p values between the order of the procedure and the intestinal retraction time, aortoiliac dissection time, clamping time, and total operative time were –0.62 (0.06), –0.47 (0.17), –0.69 (0.03), and –0.83 (0.03), respectively. HALS facilitates intestinal retraction and completion of laparoscopic aortoiliac dissection. It offers adequate exposure in pigs for aortic grafting and allows open sutured aortic anastomosis. The learning curve for HALS aortic surgery in a porcine model is short and within reach of surgeons with standard laparoscopic surgery skills, since no laparoscopic suturing is required. Training on this porcine model may be an efficient and safe way to introduce surgeons to HALS for aortoiliac reconstruction.