Faculty Bibliography

Standard therapy for most aneurysmal, occlusive, and traumatic arterial lesions has historically consisted of surgical exposure and repair or placement of an interposition bypass graft. Endovascular grafting techniques are an alternative treatment. These techniques blend stent and graft technology and enable a vascular graft to be placed from a remote access site under fluoroscopic guidance to treat a variety of arterial lesions. The major advantage of this approach is its less invasive nature. During the last 5 years, 234 endovascular grafts have been implanted at Montefiore Medical Center to treat a variety of arterial lesions including aneurysms, occlusions and traumatic or iatrogenic injuries. Although many of these procedures were complex and difficult, results have improved steadily as appropriate devices, techniques and indications have been developed. These endovascular grafts have facilitated successful treatment in many patients and have permitted correction of limb- or life-threatening lesions in some patients who would otherwise be impossible or difficult to treat. Based on this 5-year experience, it is likely that endovascular grafts will play an important role in the future treatment of various types of arterial pathology. Although the value and limitations of endovascular graft for the treatment of aneurysmal and occlusive lesions in good-risk patients remains to be precisely defined, their usage in high-risk patients and in those with iliac aneurysms and central artery traumatic false aneurysms and arteriovenous fistula already appears justified

PURPOSE: Results of percutaneous transluminal angioplasty (PTA) in selected cases have been reported to be equal or superior to those of arterial bypass graft surgery, with a lower morbidity and mortality. We performed PTA of stenotic or occlusive lesions in patients with limb-threatening ischemia, hoping to improve our overall success and decrease morbidity in this group of patients. The results of PTA in the limb-salvage setting was evaluated. METHODS: From 1992 to 1995, 307 PTAs were performed in 257 patients. One hundred sixty-one (63%) patients had diabetes mellitus, and 32 (12%) patients had renal failure. All patients were evaluated by means of pulse volume recordings and ankle brachial indices at 1 and 6 weeks after PTA and at 3 month intervals thereafter. Seventeen patients (9%) were lost to follow-up. The continued success or failure of PTA was defined by means of noninvasive vascular laboratory criteria, patency by means of pulse examination, the need for subsequent bypass grafting across the index lesion, and limb salvage. RESULTS: The 1-year patency rates for external iliac PTAs (56%) were significantly lower (P <.05) than those for common iliac PTAs (87%). Infrainguinal PTAs at the femoral, popliteal, and tibial level had 1-year patency rates of less than 15%. CONCLUSION: Common iliac artery PTA is justified in most cases in which it is feasible. However, when PTAs are performed below the inguinal ligament, the results are markedly worse. One-year patency rates of PTA in this group of patients with threatened limbs are inferior to the patency rates of arterial bypass grafts, even when these bypasses are performed with a prosthetic material. PTA should not be considered as a primary treatment modality for patients with infrainguinal arterial occlusive disease who also have limb-threatening ischemia, except in unusual circumstances

PURPOSE: To report an experimental study investigating the ability of nonporous polytetrafluoroethylene (PTFE) covering on a metallic stent to retard the development of neointimal hyperplasia (NIH). METHODS: Three groups of Hanford miniature swine underwent standardized balloon injury to both external iliac arteries. Group I animals (control) received balloon injuries only. Group II had the site of balloon injury supported by a properly sized, balloon-expandable Palmaz stent placed directly over the injury site. Group III animals received a Palmaz stent covered with PTFE graft. All animals underwent arteriography immediately after intervention and again prior to sacrifice and specimen harvest at 4 weeks. The specimens were examined grossly and histologically at the proximal, middle, and distal segments for NIH development. RESULTS: Uncovered stents developed significantly more NIH (p < 0.0001) and greater luminal narrowing (p < 0.001) than the controls. PTFE-covered stents (group III) exhibited less NIH (p < 0.001) and luminal reduction (p < 0.01) than bare stents (group II) at the middle portion of the stent-graft, but the PTFE cover had no effect on NIH and lumen reduction at the proximal or distal ends of the prosthesis. CONCLUSIONS: PTFE-covered stents retarded NIH at 4 weeks, but only at the midportion of the devices; the covering did not prevent neointimal pannus ingrowth at the proximal and distal ends

Turf issues exist largely because of emerging endovascular technologies. Vascular surgeons must develop skills with catheters, guidewires, and imaging techniques. Turf battles will result from unrestrained competition. Center/partnerships between vascular surgeons and interventional radiologists will minimize these turf battles and facilitate cross-training, which will improve the functioning of both specialists. These center/partnerships will, therefore, provide the best, most cost-effective care. Finally, all specialists who are interested in vascular disease must recognize the dangers of overproduction of competing specialists. More importantly, their leaders and specialty societies must make a serious effort to deal with this problem fairly

BACKGROUND: To determine the results of standardized ulcer treatment regimes and effects of the oral thromboxane A2 antagonist Ifetroban (250 mg daily) on healing of chronic lower-extremity venous stasis ulcers. METHODS: In a prospective, randomized, double blind, placebo-controlled multicenter study, 165 patients were randomized to Ifetroban (n = 83) versus placebo (n = 82) for a period of 12 weeks. Both groups were treated with sustained graduated compression and hydrocolloid. Ulcer size was measured weekly by tracings and computerized planimetry. A total of 150 patients completed the study. RESULTS: Complete ulcer healing was achieved after 12 weeks in 55% of patients receiving Ifetroban and in 54% of those taking a placebo with no significant differences; 84% of ulcers in both groups achieved greater than 50% area reduction in size. CONCLUSIONS: These results are likely to be useful as a benchmark for comparison with other treatment protocols concerning the care of chronic lower-extremity stasis ulcers

BACKGROUND: Previous studies have documented high rates of morbidity and death after acute peripheral arterial occlusion. To date, however, few studies have identified parameters predictive of successful therapy. METHODS: The Thrombolysis or Peripheral Arterial Surgery Trial of intraarterial recombinant urokinase or immediate operation for acute lower extremity arterial occlusion provided data on 544 patients randomized at 113 centers. A Cox proportional hazards multifactor analysis was performed to identify those main effects predictive of amputation-free survival and to document any baseline variables useful in deciding whether a patient would be treated best initially with thrombolysis or operation. RESULTS: Of 28 variables analyzed, eight main effects were predictive of amputation-free survival. These included two demographic factors: white race (risk ratio [RR] = 1.75; p = 0.003) and younger age (RR = 1.015; p = 0.046). Comorbidities comprised four of the main effects: history of central nervous system disease (RR = 1.726; p = 0.005), history of malignancy (RR = 1.615; p = 0.024), congestive heart failure (RR = 2.202; p < 0.001), or low body weight (RR = 1.007 per pound; p = 0.006). The severity of the process was also predictive, as gauged by the presence of skin color changes (RR = 1.585, p = 0.007) or pain at rest (RR = 0.503; p = 0.003). All eight effects were similar in the two treatment groups; none of these variables predicted improved outcome with one form of initial therapy over the other (i.e., there was no therapy-by-variable interaction). The length of occlusion, however, predicted whether a patient would fare better with thrombolysis or operation. With a threshold occlusion length of 30 cm, the RR for longer occlusions to shorter occlusions was 43% better in patients who received thrombolysis, whereas the situation was reversed for those who were randomized to operation. CONCLUSIONS: A variety of baseline variables can be identified that are predictive of outcome after treatment for acute lower extremity ischemia. In addition, the length of the occlusive process appears to predict whether a patient will be best served with thrombolysis or operative intervention; longer occlusions appear to respond best with an initial thrombolytic strategy

Lumbar artery aneurysms are uncommon lesions that usually present as pseudoaneurysms secondary to vessel injury. Despite their small size and retroperitoneal location, these lesions are potentially lethal once they rupture. This report describes a ruptured lumbar artery aneurysm which was successfully treated in a minimally invasive fashion. The diagnosis was suggested by computed tomography scan and confirmed with angiography. Successful treatment consisted of placing intravascular metallic coils into the lumbar artery. The literature contains only seven previous reports of ruptured lumbar artery aneurysms and these were managed either operatively or via an endovascular approach. Based upon the outcome of all reported cases, we believe that coil embolization of lumbar artery aneurysms following diagnostic angiography is an appropriate and effective mean of treating these lesions

Various endovascular techniques, including the placement of embolization coils, intravascular stents, and the use of stented grafts, have been used in the setting of traumatic upper extremity injuries. Coil embolization and stent placement are effective in a limited number of cases. Endovascular grafts have greatly extended the potential of endovascular therapy for upper extremity vascular trauma. The ideal graft material, stent, and the best mechanism for stent deployment have not been determined. In addition, long-term effectiveness of such therapy is yet to be shown. Nevertheless, endovascular grafts offer distinctive advantages in some cases and are important tools for the treatment of vascular trauma and should be included in the armamentarium of all vascular surgeons

BACKGROUND: Recent controlled trials suggest that thrombolytic therapy may be an effective initial treatment for acute arterial occlusion of the legs. A major potential benefit of initial thrombolytic therapy is that limb ischemia can be managed with less invasive interventions. METHODS: In this randomized, multicenter trial conducted at 113 North American and European sites, we compared vascular surgery (e.g., thrombectomy or bypass surgery) with thrombolysis by catheter-directed intraarterial recombinant urokinase; all patients (272 per group) had had acute arterial obstruction of the legs for 14 days or less. Infusions were limited to a period of 48 hours (mean [+/-SE], 24.4+/-0.86), after which lesions were corrected by surgery or angioplasty if needed. The primary end point was the amputation-free survival rate at six months. RESULTS: Final angiograms, which were available for 246 patients treated with urokinase, revealed recanalization in 196 (79.7 percent) and complete dissolution of thrombus in 167 (67.9 percent). Both treatment groups had similar significant improvements in mean ankle-brachial blood-pressure index. Amputation-free survival rates in the urokinase group were 71.8 percent at six months and 65.0 percent at one year, as compared with respective rates of 74.8 percent and 69.9 percent in the surgery group; the 95 percent confidence intervals for the differences were -10.5 to 4.5 percentage points at six months (P=0.43) and -12.9 to 3.1 percentage points at one year (P=0.23). At six months the surgery group had undergone 551 open operative procedures (excluding amputations), as compared with 315 in the thrombolysis group. Major hemorrhage occurred in 32 patients in the urokinase group (12.5 percent) as compared with 14 patients in the surgery group (5.5 percent) (P= 0.005). There were four episodes of intracranial hemorrhage in the urokinase group (1.6 percent), one of which was fatal. By contrast, there were no episodes of intracranial hemorrhage in the surgery group. CONCLUSIONS: Despite its association with a higher frequency of hemorrhagic complications, intraarterial infusion of urokinase reduced the need for open surgical procedures, with no significantly increased risk of amputation or death