Femoropopliteal Obstructions Research Articles

Placebo-Controlled, Double-Blind Trial of Hemodilution in Peripheral Occlusive Arterial Disease

A number of uncontrolled trials has suggested that hemodilution is effective in peripheral occlusive arterial disease. This study was aimed at proving or disproving the efficacy of hemodilution by using a randomized, placebo-controlled, double-blind crossover design. Twenty-four stable claudicants with long, collateralized femoropopliteal obstructions were treated with isovolemic hemodilution with 500 mL of 10% hydroxyethyl starch 200 and sham dilutions. Three weeks of hemodilution lowered blood and plasma viscosity, as well as hematocrit, and increased resting blood flow and pain-free walking distance. Placebo treatments produced no such favorable changes. It is concluded that hemodilution therapy can be clinically effective in patients with arterial obstructions in the lower extremities. Hemodilution seems particularly promising under hemodynamic condition of low shear stresses in vivo.

Hemodynamic Effect of Percutaneous Transluminal Angioplasty for Lower Limb Atherosclerosis

Measurements of ankle pressure index (API) and arterial flow velocity including calculation of pulsatility index (PI) from the common femoral and pedal arteries were performed in 89 limbs of 75 patients before and after percutaneous transluminal angioplasty (PTA) (63 iliac and 26 femoropopliteal). A pulsed wave Doppler ultrasound flowmeter was used. An increase of API at rest of at least 0.15 or the absence of pressure drop after exercise following PTA was used as criteria for a hemodynamically successful angioplasty. In patients with hemodynamically successful PTA of an iliac obstruction PI increased from 4.2 to 8.6 (p less than 0.001); 91 per cent of these patients improved clinically. When iliac angioplasty was hemodynamically unsuccessful, PI remained unchanged; 11 per cent of these patients improved clinically. All limbs with hemodynamically successful PTA of a femoropopliteal obstruction improved clinically and PI increased from 3.1 to 8.7 (p less than 0.001). After hemodynamically unsuccessful femoropopliteal PTA, PI remained unchanged though 25 per cent of these patients improved clinically. These results illustrate that measurement of arterial flow velocity with calculation of PI may be a useful supplement for the functional evaluation of the effect of PTA, since symptomatic response alone may be unreliable.

PLACEBO-CONTROLLED, DOUBLE-BLIND STUDY OF HAEMODILUTION IN PERIPHERAL ARTERIAL DISEASE

Twenty-four men who had stable claudication with long, collateralised femoropopliteal obstructions were treated by isovolaemic haemodilution and sham dilutions in a double-blind, placebo-controlled, crossover study. 3 weeks of haemodilution lowered haematocrit and blood viscosity and increased resting blood flow and pain-free walking distance. Sham treatment produced no such favourable changes. It is concluded that haemodilution therapy can be clinically effective in patients with arterial obstructions in the legs. It seems particularly promising when the vascular obstructions are such that low average shear stresses act on the blood in multiple, long collaterals.

Pneumatic plethysmography and 133Xe clearance as an indication of blood flow in ischemic limbs

Fifty-two patients with arteriosclerotic peripheral vascular disease had noninvasive quantitation of blood flow by pneumatic plethysmography and 133Xe clearance. Results of these tests were correlated with arteriograms. Segmental obstruction at the aortoiliac area reduced pulse volume to 33% of control and muscle blood flow to 60% of control. Occlusion of the superficial femoral artery alone similarly reduced pulse volume to 36% of control and muscle blood flow to 61% of control. With combined aortoiliac and femoropopliteal obstruction, the pulse volume was markedly reduced to only 15% and muscle blood flow to 39% of normal. Pneumatic digital plethysmography and isotope-clearance provide simple, reliable and reproducible means for noninvasive measurement of blood flow, and may obviate some patients from the hospitalization, hazard, and discomfort of arteriography.

ARTERIOGRAPHIC FINDINGS IN THROMBOANGIITIS OBLITERANS

In a series of 16 patients with histologically confirmed TAO, arteriography defined the characteristic pattern and the distribution of the peripheral arterial disease, pin-pointed optimal sites for confirmatory biopsies, and revealed those patients suitable for autogenous vein bypass grafts. Diffuse vascular narrowing, occlusions, and a segmental pattern of involvement were commonly observed. Collaterals frequently had a corkscrew configuration proximally and a tree-root appearance distally. In one-half of the lower limbs examined irregularities of the arterial wall, stenoses, or occlusions were shown in the femoropopliteal segment. Four patients were found suitable for autogenous vein by-pass graft of the femoropopliteal obstruction.

Femoro-popliteal arterial obstructions. Late results of teflon prostheses and arterial homografts.

Femoro-popliteal arterial obstructions. Late results of teflon prostheses and arterial homografts.