Current trends in lower extremity revascularization.

Femoropopliteal bypass is the traditional management of superficial femoral artery lower extremity athero-occlusive disease for lifestyle-limiting claudication and critical limb ischemia. Over the last decade, with the advent of new technologies, an increasing number of endovascular interventions are being used to treat femoropopliteal disease. Endovascular interventions are attractive to patients and physicians because of their decreased morbidity and mortality, despite the possibility of reduced durability. A multitude of techniques are available, without a clear consensus as to which one is best. This article reviews the current endovascular management options available for femoropopliteal occlusive disease, and the published results with each modality.

Aortic graft infection: update on management and treatment options.

Replacement of the abdominal aorta, whether by autogenous or prosthetic conduit, has been an a priori requisite in the vascular surgeon's armamentarium since its technical feasibility was described in the early 1950s. The Achilles' heel of this operation, in spite of the progress made over the last half century, is still, however, aortic graft infection. Though survival and limb salvage rates have improved over time-commensurate with advances in surgical technique, critical care, and antimicrobial agents-the prevention and treatment of aortic graft infection remains a formidable challenge to the vascular surgeon. The authors herein review the current literature on this topic with an emphasis on the surgical management options available and suggest an individualized operative strategy based on patient as well as microbial factors to attain the best possible outcome.

Dose-dependent inhibition of myointimal hyperplasia by orally administered rapamycin.

Myointimal hyperplasia (MIH) after vascular intervention is a major problem. Recent reports describing elimination of within-stent restenosis by means of rapamycin-eluting stents prompted us to examine the effect of systemic oral rapamycin on MIH induced by arterial trauma. We studied the effect of oral rapamycin on MIH after rabbit aorta balloon injury. Thirty-five New Zealand white rabbits (2.5-3 kg) had aortic injury and were given either no rapamycin (control), 0.1 (low dose) rapamycin mg/kg/day, or 0.4 mg/kg/day (high dose). Rapamycin was started 1 week before injury and continued for 3 (4 weeks total) or 6 weeks (7 weeks total) post-injury. Sections were analyzed to measure aortic intima/media area ratios (I:M) at either 3 or 6 weeks. At 3 weeks, the I:M (mean +/- SD) for controls was 0.53 +/- 0.1; for low dose, 0.17 +/- 0.13; and for high dose, 0.24 +/- 0.07 (p < 0.001 vs. control). At 6 weeks, the I:M for controls was 0.52 +/- 0.12; for low dose-4 weeks, 0.29 +/- 0.15; low dose-7 weeks, 0.33 +/- 0.07; and high dose-4 weeks, 0.47 +/- 0.16. At 6 weeks only the difference between the low dose-4 weeks and control I:M ratios was significant (p = 0.018). The results confirm earlier studies showing that systemic rapamycin inhibits MIH after arterial injury when drug therapy is started before injury. Therapy for 3 or 6 weeks after injury yields similar inhibition, indicating that exposure to the drug early in the response to injury is more important than prolonged exposure. We observed a paradoxical relation between dose and degree of MIH inhibition, with the low dose being more effective than the high dose at both time intervals studied. Overall, the results suggest that oral rapamycin therapy might be a useful adjunct to clinical interventions at risk for development of MIH.

Duodenocaval fistula: a late complication of retroperitoneal irradiation and vena cava replacement.

Duodenocaval fistula (DCF), an unusual pathology, is associated with a 40% mortality rate in the 36 patients previously reported. Although migrating or ingested foreign bodies, trauma, and peptic ulcer disease are often described etiologies, 11 patients have been described who developed DCF after resection of retroperitoneal tumors, 9 of whom also had postoperative radiotherapy. We report two patients who developed DCF after resection of retroperitoneal tumors followed by radiation therapy. The first patient, a 56-year-old female, presented with upper gastrointestinal hemorrhage requiring transfusion caused by a duodenoprosthetic caval fistula 7 years after successful resection of a retroperitoneal leiomyosarcoma and replacement of the inferior vena cava followed by radiation and chemotherapy. The second patient, a 37-year-old male who had previously undergone resection of a retroperitoneal sarcoma followed by external radiotherapy, developed massive upper and lower gastrointestinal bleeding secondary to a duodenocaval fistula. The etiology, diagnosis, and treatment of DCF are analyzed with an emphasis on DCF following resection and irradiation of retroperitoneal tumors. In most patients, "spontaneous" DCF have occurred as a late complication of high-dose radiation for carcinoma of the right kidney or retroperitoneal structures.

Superiority of autogenous arteriovenous hemodialysis access: maintenance of function with fewer secondary interventions.

The National Kidney Foundation Kidney Disease Outcomes Quality Initiative (NKF K/DOQI) guidelines have advocated autogenous arteriovenous fistulae as a primary procedure for hemodialysis access. This study compared the clinical outcomes between autogenous and prosthetic arteriovenous hemodialysis accesses, determining factors contributing to primary and secondary patency and function. Associated risk factors and number of interventions required to maintain secondary patency in each cohort were also assessed. A vascular database review of consecutive hemodialysis access procedures performed during a 36-month period (January 1999 to December 2001) at an academic institution was conducted. Life-table and log-rank analyses were used to analyze patency rates. Univariate and multivariate analysis was used to analyze risk factor influence on patency and function. A total of 231 upper extremity arteriovenous access procedures were performed in 209 patients during this period. One hundred autogenous accesses were created in 100 patients, 68 being forearm Brescia-Cimino arteriovenous fistulae. A total of 131 prosthetic accesses (ePTFE) grafts were also placed during this period in 109 patients. The demographic profiles of both cohorts were similar. Primary patency at 1 and 2 years was 56% (CI 45-76%) and 39% (CI 28-50%), respectively, in the autogenous group, and 36% (CI 26-45%) and 9% (CI 3-14%), respectively, in the prosthetic group. Differences in secondary patency at 1 year and 2 years were not significant (64% [CI 54-74%] and 53% [CI 42-65%] in the autogenous group vs. 65% [CI 55-73%] and 46% [CI 36-55%] in the prosthetic group). Secondary interventions were required in 87% of the prosthetic cohort (average 0.92 procedures/patient/year) and 57% of the autogenous cohort (average 0.53 procedures/patient/year). Multivariate analysis of associated risk factors demonstrated no significant effects on either primary or secondary patency in both groups. Autogenous accesses have superior primary patency and maintain equal secondary patency with significantly fewer interventions. These data strongly support the NKF K/DOQI guidelines recommending creation of autogenous access whenever possible. These outcomes can provide significant health-care cost benefits when using an algorithm favoring primary creation of autogenous access for hemodialysis.