Purpose: Mycotic pseudoaneurysms (MPA) remain challenging clinical problems. Primary surgical management includes control of hemorrhage and debridement of the infected arterial wall. Because critical ischemia may develop after arterial resection, revascularization has been a secondary goal of treatment. Standard anatomic graft placement or prosthetic bypass grafting has been compromised by a high rate of recurrent infection. Extra-anatomic reconstruction is preferred, with the basic goals being threefold:(1) the use of autogenous graft material to reduce the risk of reinfection; (2) the avoidance of significant size mismatches; and (3) graft placement that is anatomically inaccessible, because drug abuse causes many of these lesions. This study reviews a recent series of MPAs applying these treatment goals. Methods: In a 2-year period, the superficial femoral and proximal popliteal veins were used in the repair of eight MPAs of the common femoral (5), common iliac (1), and brachial (1) arteries, and the infrarenal aorta (1). Most patients (5 of 7) were known intravenous drug users, who had a painful pulsatile mass in an injection area. Two patients had systemic sepsis, one patient with an infected common iliac pseudoaneurysm and one patient with an MPA of the infrarenal aorta. The diagnosis of MPA was made by means of duplex/computed tomography scanning and confirmed by means of arteriography in all cases. Results: Obturator bypass grafting was performed by using a reversed deep leg vein in the five femoral MPAs. An ilioiliac, cross-pelvic bypass grafting procedure with a deep vein was used to repair an MPA of the common iliac artery. A deep vein was also used as a "pantaloon" aortobiiliac graft and for a brachial artery repair. Staphylococcus aureus was revealed by means of cultures in nearly all cases. Distal arterial perfusion was normal after reconstruction. Patients had no significant postoperative leg swelling. No new venous thrombosis below the level of deep vein harvest was revealed by means of duplex scanning. There were no septic complications. Conclusion:The superficial femoral/popliteal veins may be particularly useful for limb revascularization in patients with MPAs. This autogenous conduit provides an excellent size-match and a suitable length for reconstruction, because peripheral, axial arteries are generally affected. No clinically significant limb morbidity was related to deep vein removal. Late follow-up is challenging in such cases, but will be required to accurately determine the durability of this strategy.

Animal models of arterial injury have failed to predict effective therapy to prevent restenosis in humans. While this may relate to species differences in the control of smooth muscle cell growth, many studies have used nonatherosclerotic animals, thereby failing to consider the importance of atherosclerosis in the response to injury. In an attempt to model human restenosis more accurately, we characterized the response to angioplasty in atherosclerotic monkeys. Twenty-one cynomolgus monkeys were fed an atherogenic diet for 36 months (plasma cholesterol, 12 +/- 1 mmol/L [470 +/- 23 mg/dL]). Angioplasty was then performed in the left iliac artery. After 4, 7, 14, or 28 days, bromodeoxyuridine was given to label proliferating cells, and iliac arteries were fixed in situ at physiological pressure (5 or 6 animals at each time point). Comparisons were made between injured and uninjured iliac arteries within each animal. Angioplasty often fractured the intimal plaque and media, transiently increasing lumen caliber (4 days: lumen area, 232.5 +/- 80.3% of control) and artery size as reflected by external elastic lamina area (EEL). EEL and lumen caliber returned to baseline by 7 days. Proliferation was increased throughout the artery wall at 4 and 7 days and later declined to control rates (4 days, injured versus uninjured: adventitia, 45.0 +/- 6.2% versus 16.3 +/- 7.2%; media, 8.6 +/- 2.6% versus 0.6 +/- 0.1%; intima, 16.0 +/- 5.6% versus 7.8 +/- 3.1%). The intima thickened markedly from 14 to 28 days, but an increase in EEL generally prevented further loss of the short-term gain in lumen caliber (28 days, percent of control: intimal area, 342.8 +/- 88.9%; EEL area, 150.2 +/- 28.9%; lumen area, 119.3 +/- 21.3%). The response to angioplasty in atherosclerotic monkeys appears to closely resemble that in humans. Plaque fracture, delayed recoil, intimal hyperplasia, and remodeling may each be important in determining late lumen caliber. This primate model should prove valuable in defining cellular and biochemical mediators of human restenosis.

Regression of acute DVT begins early and continues for at least 9 months. It is accompanied by significant enhancement of the endogenous fibrinolysis, which appears to be primarily mediated by increased tPA activity. Patients who have thrombus propagation in spite of standard antithrombotic therapy may have failure of activation of endogenous fibrinolysis.

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