The talent endoluminal AAA stent-graft system. Report of the phase I USA trial, and summary of worldwide experience

In the United States, the Phase I Feasibility Study under IDE G970065 was approved by the Food and Drug Administration on 04/11/97. The approved protocol called for implantation of the bifurcated Talent spring stent-graft system on patients who are high-risk candidates for conventional surgery because of cardio-respiratory, medical, general, or local anatomical reasons which would likely complicate the technical execution of the operation or be accompanied by a high expected mortality rate. Patient enrollment was complete with 16 cases as of September 26, 1997. This was a multicenter experience involving five different sites. This is an ongoing study and patients, of course, will continue to be followed longitudinally. Phase II will likely be approved by the FDA for initiation in January or February of 1998. Standard-risk AAA patients will be entered into the study at this time; comparison with concurrent controls will be used for comparison with conventional surgery.

Outpatient endovascular intervention: is it safe?

PURPOSE

To evaluate the feasibility and safety of outpatient percutaneous endovascular intervention in the treatment of arterial occlusive disease.

METHODS

The records of 134 patients who underwent 151 outpatient endovascular procedures between 1992 and 1997 were reviewed retrospectively. According to established protocol, focal lower limb (n = 145) and subclavian (n = 6) arterial lesions requiring relatively straightforward endoluminal interventions were appropriate for outpatient management provided the patients were free of significant comorbidities. A percutaneous transfemoral approach was used for lower limb lesions, while subclavian angioplasty was performed via a brachial access. Heparin anticoagulation was administered conservatively. Patients were discharged 3 hours after sheath removal.

RESULTS

The majority (98%) of patients were discharged as planned. Three (2%) patients were observed overnight in the hospital for treatment of acute iliac artery thrombosis, puncture-site bleeding, and suboptimal angioplasty. No patient required hospitalization following discharge. Periprocedural morbidity was confined to 2 (1.5%) groin hematomas and 1 (0.7%) femoral pseudoaneurysm.

CONCLUSIONS

Outpatient endovascular intervention appears safe; however, proper case selection and technical excellence are inseparable components for the success of this strategy.

Percutaneous femoral puncture for endovascular treatment of occlusive arterial lesions

BACKGROUND

Percutaneous femoral arterial access is a most important and difficult aspect of endovascular intervention, and the source of most complications.

METHODS

A retrospective review was made of the authors' 9-year experience with 755 femoral punctures for the endovascular treatment of occlusive disease. The main focus was the evolving success rate with percutaneous arterial entry and the incidence of access-related complications.

RESULTS

Cutdowns were frequent during the first 2 years, 54% and 17%, respectively, decreasing to 5% or lower by the third year. The incidence of femoral hematoma and other complications mirrored the same learning curve. After cutdown, wound infections and lymph leakage occurred in 2.4% each, and prolonged significant pain in 5%.

CONCLUSIONS

Percutaneous puncture is a crucial skill in endovascular intervention. Practicing vascular surgeons can expect a significant learning curve. Performance can be optimized through intensive basic and advanced training and preceptorship. The cutdown approach is neither necessary nor acceptable for most endovascular procedures.

Healing of colonic ischemic anastomoses in the rat: role of superoxide radicals

PURPOSE

The aim of this study was to evaluate the role of superoxide radicals in the healing of ischemic colonic anastomoses in the rat.

METHODS

Adult male Wistar rats were used in a factorial design with two factors (normal or ischemic colonic anastomoses) each having two levels (treatment with saline or allopurinol). Colonic anastomoses were performed either in normal or previously devascularized colons (ischemic anastomoses) at identical locations, using the same technique. On the fourth postoperative day, animals were killed, and specimens were taken for determinations.

RESULTS

Ischemic anastomoses displayed significant increases in superoxide radical (assayed as superoxide anion), superoxide dismutase, and glutathione peroxidase concentrations. Bursting strength and hydroxyproline levels were also significantly lower in these anastomoses. Allopurinol administration elicited a significant decrease in superoxide anions and raised both bursting strength and hydroxyproline levels only in ischemic anastomoses.

CONCLUSIONS

Superoxide radicals are involved in the delay in healing of ischemic anastomoses. Allopurinol lowers superoxide anion production and has beneficial effects on the cicatrization of ischemic anastomoses.

Evolving indications for and early results of carotid artery stenting

BACKGROUND

While carotid endarterectomy continues to be the gold standard of treatment for most patients with significant carotid artery disease, there are cases where lesion or anatomy-related factors create situations less than ideal for conventional surgery. Other therapeutic modalities, such as endoluminal stenting, may represent reasonable options for such patients.

METHODS

Thirty-three patients with 70% or greater internal carotid artery lesions were treated by endovascular stent placement from July 1994 through June 1996. Indications included transient ischemic attacks in 20 and previous stroke in 4; and 9 were asymptomatic.

RESULT

Stents were placed successfully in all instances. Mortality and stroke rates were zero. All patients remained asymptomatic during follow-up (mean 8 months), and stent patency by duplex ultrasound has been 100%. A single instance of intrastent restenosis has been observed.

CONCLUSIONS

Endoluminal stenting is an investigational technique of unproven efficacy and long-term durability. Yet it appears technically feasible, and possibly reasonable, as an alternate option for cases unfavorable for standard surgery.

Miniincisional ligation of incompetent perforating veins of the legs

PURPOSE

The purpose of this study was to determine the effectiveness of a new surgical procedure for interrupting incompetent perforating calf veins in patients with recalcitrant venous ulcers.

METHODS

Eighteen patients with venous ulcerations in 26 limbs had incompetent perforators diagnosed by duplex scanning. All were taken to the operating room, where the fascial defects through which the perforators coursed were obliterated by a "pursestring" permanent suture placed on the leg fascia. Follow-up duplex scanning was carried out within 2 weeks of the procedure and every 6 months thereafter. The mean follow-up in this series was 22 months.

RESULTS

Initial success in obliterating the perforators was noted in 24 (92.3%) of 26 legs. Three subsequent failures occurred within 6 months for a midterm success rate of 80.7%. No wound complications or infections occurred. All ulcers healed within 6 weeks of the procedure (mean, 23 days) in the successfully treated patients.

CONCLUSIONS

Miniincisional ligation of incompetent perforating veins is easy to perform and has very encouraging early results.

Percutaneous revascularization of an extensively diseased saphenous vein bypass graft with a saphenous vein-covered Palmaz stent

A 68-year-old man developed unstable angina 12 years following coronary artery bypass surgery. Angiography revealed an extensive area of severe stenosis and diminished distal flow in a right coronary artery vein bypass graft. Given the high distal embolism rate associated with conventional catheter-based treatment of old degenerated vein grafts, the diseased area was "relined" with a composite autologous saphenous vein-covered stent. The procedure was performed using modifications of standard PTCA methods and resulted in a widely patent, smooth lumen. This initial case demonstrates that a degenerated saphenous vein graft can be successfully revascularized with an autologous saphenous vein-covered stent in an attempt to minimize the potential complications of standard catheter-based revascularization methods.

Techniques for endovascular recanalization of supra-aortic trunks

The supra-aortic are no stranger to endovascular interventions. Since the 1980s, interventionists have been evaluating and refining the use of transluminal techniques for recanalizing stenotic and occlusive lesions in these large-bore, high-flow vessels. The authors present their methodologies for evaluating, selecting, and treating supra-aortic lesions with balloon angioplasty and stenting. Helpful suggestions are offered for optimizing the outcome of these endovascular approaches to atherosclerotic occlusive disease in the supra-aortic trunks.