Phosphorus 31 nuclear magnetic resonance spectroscopy suggests a mitochondrial defect in claudicating skeletal muscle.
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OBJECTIVE: Decreased oxygen supply is generally accepted as the primary cause of muscle dysfunction in patients with peripheral arterial occlusive disease (PAOD) and intermittent claudication, although reported morphologic changes in the mitochondria of claudicating muscle suggest that impaired energy utilization may also play a role. With the measurement of the phosphate-rich compounds of muscle energy metabolism (adenosinetriphosphate [ATP], adenosinediphosphate [ADP], and phosphocreatine [PCr]) and pH, phosphorus P 31 magnetic resonance spectroscopy ((31)P MRS) provides a unique, noninvasive method to investigate this hypothesis further. METHODS: Calf muscle bioenergetics were studied in 12 men with moderate claudication (ankle-brachial index >/=0.5 and .5, Pearson moment correlation). CONCLUSIONS: Phosphorus 31 MRS provides the first direct evidence of defective energy metabolism in the mitochondria of claudicating calf muscle. This defect appears to be independent of both arterial flow and the severity of occlusive disease in patients with mild to moderate claudication. Coupled with documented ultrastructural and DNA abnormalities in the mitochondria of claudicating skeletal muscle, these data provide evidence for a secondary cause of muscle dysfunction in intermittent claudication. (+info)
Intestinal permeability is increased in patients with intermittent claudication.
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PURPOSE: Intermittent claudication can be regarded as repeated ischemia reperfusion injury, which can induce a generalized increase in vascular permeability, including in intestine. The lactulose mannitol test (L/M test) was performed in patients with intermittent claudication to evaluate the change in intestinal permeability when they were forced to walk. METHODS: The L/M test was performed in 11 patients with intermittent claudication and 11 control subjects without intermittent claudication. The test was performed at rest and after exercise. Patients walked on a treadmill until they stopped because of pain. The control subjects were forced to walk as far as 200 m on a treadmill. The L/M test was repeated in the patients after successful arterial reconstruction. Then the patients were instructed to walk the same distance at the same speed as they had before surgery. RESULTS: In patients, the mean L/M ratio after exercise was significantly higher than the mean L/M ratio when they were at rest (0.068 +/- 0.053 vs 0.022 +/- 0.009, P <.05). In control subjects, however, no significant difference was observed between the mean L/M ratios after exercise and at rest. The mean L/M ratio after exercise, decreased from 0.068 +/- 0.053 to 0.018 +/- 0. 016 after successful arterial reconstruction (P <.05) in patients. CONCLUSION: Intestinal permeability, determined by means of the L/M test, significantly increased in patients with intermittent claudication after exercise, and it diminished after arterial reconstruction. The L/M test is, consequently, a new noninvasive method to reflect ischemia in lower limbs during exercise. (+info)
Above-knee prosthetic femoropopliteal bypass for intermittent claudication. Results of the initial and secondary procedures.
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OBJECTIVES: [corrected] to report the results of primary and secondary prosthetic above-knee femoropopliteal bypass for intermittent claudication. DESIGN: a retrospective study in a University hospital. PATIENTS: one hundred and twelve operations performed in 103 patients (26 women) between January 1990 and June 1997. METHODS: a comparison of primary assisted patency was made between Dacron and PTFE, between men and women and between operations performed early and late in the study period. Patency of secondary procedures was also studied. RESULTS: there were no operative deaths. The 5-year survival rate was 81% and equal to that of a demographically matched population. The primary assisted graft patency was 58% after two years. Women had a significantly better graft patency than men (79% vs. 49%). The type of graft and the date of the operation did not influence the outcome. Forty of the 55 occluded grafts were subjected to a redo procedure with a 1-year patency of 29%. CONCLUSIONS: the results after prosthetic above-knee femoropopliteal bypass procedures are disappointing, and a controversy persists as to whether this operation should be performed for intermittent claudication. The results of secondary procedures are even worse, and perhaps should only be considered in patients suffering critical ischaemia. (+info)
Endoluminal femoropopliteal bypass for intermittent claudication.
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OBJECTIVES: (i) to describe our initial clinical experience with endoluminal femoropopliteal bypass using a technique developed in a cadaveric model; (ii) to identify areas requiring technical modification to improve patency and complication rates. DESIGN: prospective, experimental pilot study. MATERIALS AND METHODS: fourteen consecutive patients with disabling intermittent claudication and superficial femoral artery occlusion underwent endarterectomy through a groin incision and endoluminal placement of a polytetrafluoroethylene graft. Follow-up was by duplex ultrasound and arteriography. RESULTS: two endovascular technical failures required conversion to open surgery. The cumulative primary (1 degrees), 1 degrees-assisted and secondary (2 degrees) patency rates at 1 year were 35.7%, 42.8% and 71.4% respectively; at 2 years the patency rates were 14.3%, 31.2% and 57.1%. Twenty-three endovascular interventions were required to maintain graft patency in 10 patients. Five patients subsequently required conventional bypass, of whom two proceeded to major amputation because of graft infection. Seven endovascular grafts remain patent at a mean follow-up of 50 months. CONCLUSIONS: this minimally invasive surgical technique is feasible, with acceptable patency rates. However, considerable investment of time and resources is required to maintain graft patency. With increasing experience and improved technical design, this procedure may offer a real alternative to conventional surgery in patients disabled by short-distance claudication. (+info)
Limb salvage and popliteal aneurysms: advantages of preventive surgery.
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OBJECTIVES: to assess the prognosis of atherosclerotic popliteal aneurysms (APAs), according to whether they were occluded or patent at the time of diagnosis. DESIGN: retrospective study. PATIENTS AND METHODS: fifty-two APAs were investigated in 35 patients. Nineteen were occluded (group I) and 33 patent (group II). In group I, 11 lower limbs had critical ischaemia, and eight had severe claudication. In group II, 27 were asymptomatic, 3 were painful, and 3 presented with symptomatic distal occlusion. In group I, treatment consisted of six bypasses, five thrombectomies, four thrombolyses, but for five APAs, no revascularisation was possible due to lack of runoff. In group II, 30/33 APAs were treated by graft replacement; the other three were not operated on due to the patients>> poor general condition. RESULTS: the 4-year survival rate was 72% in group I vs. 77% in group II, and the limb salvage rate was 72% in group I vs. 100% in group II, p<0.01. CONCLUSION: prophylactic treatment of asymptomatic popliteal aneurysms may avoid amputation caused by thrombosis and embolisation of runoff. (+info)
Arm vein conduit is superior to composite prosthetic-autogenous grafts in lower extremity revascularization.
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PURPOSE: Various alternative conduits have been used for lower extremity revascularization when an adequate ipsilateral greater saphenous vein is absent. This study compared the effectiveness of all-autogenous multisegment arm vein bypass grafts with that of composite grafts composed of combined prosthetic and autogenous conduits. METHODS: One hundred fifty-three lower extremity revascularization procedures performed between 1990 and 1998 were followed up prospectively using a computerized vascular registry. The grafts were composed of spliced arm vein segments with venovenostomy in 122 and of composite prosthetic-autogenous conduit in 31. Arm vein conduit was prepared by means of intraoperative angioscopy for valve lysis and identification of luminal abnormalities in 47.7% of cases. RESULTS: Bypass graft configurations were as follows: femoropopliteal (12 arm vein, 2 composite); femorotibial (75 arm vein, 23 composite); femoropedal (14 arm vein, 6 composite), and popliteo-tibial/pedal (21 arm vein, 0 composite). The indication for surgery was limb salvage in 98% and disabling claudication in 2% of cases. The mean follow-up was 25.1 months (range, 1 month to 7.9 years). Overall survival at 4 years was 51%. Overall patency and limb salvage rates were as follows: primary patency, at 1 year-arm vein, 76.9% +/- 4.8%; composite, 59. 5% +/- 9.6% (P =.02); at 3 years-arm vein, 70.0% +/- 8.0%; composite, 43.7% +/- 12.4% (P <.01); and at 5 years-arm vein, 53.8% +/- 8.7%; composite, 0%; secondary patency, at 1 year-arm vein, 77.5% +/- 4. 6%; composite, 59.8% +/- 9.5% (P =.02); at 3 years-arm vein, 70.7% +/- 7.5%, composite, 44.9% +/- 13.1% (P <.01); at 5 years-arm vein, 57.7% +/- 8.0%; composite, 0%; limb salvage, at 1 year-arm vein, 89. 3% +/- 3.7%; composite, 73.9% +/- 8.9% (P <.01); at 3 years-arm vein, 80.5% +/- 7.0%; composite, 49.6% +/- 14.3% (P <.01); at 5 years-arm vein, 76.3% +/- 9.9%; composite, 0%. CONCLUSION: In this study, multisegment autogenous arm vein was used successfully in a wide variety of lower extremity revascularization procedures and achieved good long-term patency and limb salvage rates, well in excess of those achieved with composite prosthetic-autogenous grafts. The use of autogenous conduit appears to offer superior results to composite conduit in lower extremity revascularization. The superior durability of arm vein makes it one of the alternative conduits of choice when an adequate greater saphenous vein is not available. (+info)
The durability of endovascular treatment of multisegment iliac occlusive disease.
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PURPOSE: The effectiveness of endovascular treatment of multisegment iliac occlusive disease (involving two or more common and/or external iliac arteries) was determined. METHODS: All patients who underwent angioplasty or stenting of at least two separate iliac artery segments were identified. Demographic data were recorded. Technical success, hemodynamic success, and aortoiliac primary and primary-assisted patency were analyzed by using the Society for Vascular Surgery and International Society for Cardiovascular Surgery (SVS/ISCVS) criteria. Multivariate, life table analysis was used as a means of determining outcome predictors. RESULTS: Eighty-seven patients underwent 207 iliac artery angioplasties and 115 iliac artery stents, which were performed in 210 iliac segments for disabling claudication in 60% of cases, for rest pain in 17% of cases, and for tissue loss in 23% of cases. Two iliac segments were treated in 64% of patients, three segments were treated in 28% of patients, and four segments were treated in 8% of patients. The complication rate was 11%. Initial hemodynamic success was achieved in 72% of cases. Clinical improvement occurred in 88% of patients. Subsequent endovascular reintervention was required in 29% of patients, whereas surgical inflow procedures were required in 14% of patients to maintain aortoiliac patency. The mean time from the primary intervention to the first reintervention was 10 +/- 3 months. At 6, 12, and 36 months after intervention, the primary patency rates of the aortoiliac segment were 76%, 61%, and 43%, respectively, and the primary assisted patency rates were 95%, 87%, and 72%, respectively. Only the presence of an external iliac artery stenosis adversely affected both primary and assisted-primary patency. At 6, 12, and 36 months, the aortoiliac primary patency rates in patients without the presence of an external iliac artery stenosis were 88%, 78%, and 69%, respectively, compared with 68%, 47%, and 18%, respectively, in patients with external iliac artery lesions (P <. 0001). CONCLUSION: Endovascular therapy for multisegment aortoiliac occlusive disease has acceptable patency rates; however, reintervention is often needed. The presence of external iliac artery disease is a significant predictor of poor outcome. (+info)
Chronic ergot toxicity: A rare cause of lower extremity ischemia.
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Chronic ergot toxicity is a rare cause of lower extremity ischemia. The cornerstone of therapy in ergot toxicity is to discontinue the use of caffeine, cigarettes, and all ergot-containing medications. Although multiple different therapies have been recommended for acute toxicity, no specific treatment is uniformly recommended in chronic toxicity. We present a case of long-term ergot use for migraine headaches in a woman who had severe chronic lower extremity claudication. This case demonstrates the unique features associated with the diagnosis and management of chronic ergot toxicity. We recommend a conservative approach consisting of observation, antiplatelet agents, and the discontinuance of ergots. If symptoms progress to rest pain or gangrene, surgical treatment should be considered. (+info)