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Biomedical subjects

G Andros

Publications and source records attributed to G Andros.

At least 37 records · Page 2Linked to original sources
PubMed1990

Can duplex scanning replace arteriography for lower extremity arterial disease?

This preliminary study was undertaken to determine if surgeons would choose different intervention for lower extremity occlusive disease when given basic clinical information and data from either a duplex scan or arteriogram. Information on degree of stenosis from duplex scans and arteriograms of 29 patients was indicated on an anatomical line drawing along with the ankle blood pressures and a brief clinical description. Based on these data sheets, six vascular surgeons chose a clinical plan in a blinded fashion for each patient. Each plan was placed into one of eight possible categories for comparison using the kappa statistic. Intraobserver agreement between surgeons' decisions based on duplex scanning versus those based on arteriography was very good (mean kappa .70 with exact agreement in 76%). Interobserver agreement between different surgeons' decisions based on the same studies was significantly less (mean kappa 0.56, p less than .05). Significant disparity in clinical approach occurred in 43% of the patients with nearly identical duplex scan and arteriogram reports, suggesting that much of the discrepancy lies in the clinical decision-making process. Clinical decisions made using duplex scans are very similar to those made using arteriograms. This technique can limit the need for arteriography in assessing patients with lower extremity arterial occlusion disease.

Angiography↗
PubMed1990

Preoperative duplex scanning prior to infrainguinal revascularization.

Arterial occlusive disease has been successfully evaluated with ultrasonography prior to infrainguinal revascularization; this technique contributes to design of operation and, in the case of a bypass, to the selection of a venous conduit. Techniques of black-and-white and color sonoangiography of the peripheral arteries and veins comprise imaging and blood velocimetry. Velocity and flow measurements and other data in the literature that compare ultrasound and radiologic techniques indicate that sonoangiography is already the "practical standard" for vein selection and will have a growing role in preparation for infrainguinal revascularization.

Arterial Occlusive Diseases↗
PubMed1990

Successful percutaneous angioplasty after failed femorodistal bypass.

Although balloon angioplasty for the management of failing bypass grafts has been well documented, little mention has been made of its use in treating the occlusive lesion within the native artery after a failed bypass graft. We report our experience with five patients in whom successful balloon angioplasty was carried out subsequent to failure of a femoral popliteal bypass graft. Increasingly aggressive percutaneous therapy of arterial occlusive disease may now be expanded to include a unique group of patients with chronically failed bypass grafts and occlusive disease within the native artery conducive to percutaneous transluminal angioplasty. This group of patients would previously have been relegated to repeat bypass grafts with its inherently inferior patency and recognized added technical demands. Percutaneous balloon angioplasty appears to be a plausible alternative in selected cases for repeat lower extremity revascularization.

Aged↗
PubMed1989

Lateral plantar artery bypass grafting: defining the limits of foot revascularization.

We placed 20 bypass grafts to the lateral plantar artery in 18 extremities to salvage feet with wet (12) or dry (six) gangrene; 15 grafts were implanted in men (75%), and five were implanted in women (25%). The median age was 65 years. All except two patients had diabetes; eight were treated with insulin. One patient had Buerger's disease, and another had vasculitis with chronic lymphocytic leukemia. History of smoking (65%), hypertension (53%), heart disease (71%), and osteomyelitis in the foot (35%), were noted. Cultures were positive in 15 gangrenous feet, 11 with gram-negative bacilli. Four long femoroplantar bypasses were placed. Ten short grafts were placed from the popliteal artery, and six jump grafts were placed distal to a femoropopliteal or tibial bypass. Hospital stay ranged from 8 to 38 days (median 16 days), and there were two in-hospital deaths. Transmetatarsal or button toe amputations were performed in nine feet. There were two below-knee amputations, one with a patent graft, for a foot salvage rate of 89% at 2 months. In four instances the gangrenous ulcers took longer than 6 months to heal; all other wounds healed within 6 months. The primary and secondary patency rates were 85% at 1 month, and 73% at 3 months and thereafter. Four of five graft failures occurred in the two legs with repeat bypass graftings. All patients with successful revascularization are able to walk, and seven returned to work full time.

Adult↗
PubMed1989

Changes in peripheral hemodynamics after percutaneous transluminal angioplasty.

We measured ankle/arm pressure indexes and blood flow rates before and after performing percutaneous transluminal angioplasty in 36 extremities. Flow rates through the leg were determined with a magnetic resonance blood flow scanner. All patients had claudication; one had gangrene, another had an ulcer, and two complained of rest pain. The median age was 65 years, and 72% were men. There were 25 dilations of the iliac artery, 12 of the superficial femoral artery, and eight of the popliteal arteries; nine patients had two arterial segments dilated. Nineteen legs had ankle/arm pressure indexes before percutaneous transluminal angioplasty of less than 0.80 (range 0.51 to 0.75); their flow rates averaged 40 +/- 20 (SD) ml/min. After percutaneous transluminal angioplasty flow and pressure increased significantly in 14 of these 19 legs, and three had no hemodynamic improvement; in one leg only pressure and in another only flow increased significantly. The remaining 17 extremities had ankle/arm pressure indexes before percutaneous transluminal angioplasty ranging from 0.81 to 1.09; their flow rates averaged 53 +/- 27 (SD) ml/min. Abnormal flow rates were detected in 15 of these 17 extremities. With near-normal ankle/arm pressure indexes no significant increase in pressure was anticipated. Flow rates augmented to 75 +/- 28 (SD) ml/min after percutaneous transluminal angioplasty; a significant increase in flow was noted in 12 legs (71%). For patients with ankle/arm indexes before percutaneous transluminal angioplasty of less than 0.80, either pressure or flow measurements should corroborate the benefits of the operation, whereas if the ankle arm index is greater than 0.80, flow measurements are most likely to substantiate changes in peripheral hemodynamics.

Aged↗
PubMed1988

Bypass grafts to the ankle and foot.

Two hundred forty-three bypasses to paramalleolar arteries were performed in 224 extremities of 208 patients since 1971; 166 were implanted in men (68%) and 77 in women (32%). The median age was 73 years. Gangrene (61%), nonhealing ulcer (15%), rest pain (22%), and trauma (2%) were the indications for bypass. Usual risk factors were noted: diabetes (65%), smoking (51%), heart disease (46%), and hypertension (45%). The extent of occlusive disease dictated three graft configurations: long grafts originating in arteries proximal to the adductor tendon (n = 111), short grafts originating at or below the popliteal artery (n = 88), and jump grafts originating near the distal end of a previous femorodistal bypass (n = 44). The association between diabetes (incidence 80%) and gangrene (75%) in patients with short grafts was statistically significant (p less than 0.01). The 2-year secondary patency rate of long in situ grafts was 92% compared with 72% for other autogenous vein long grafts. The limb salvage rate for all autogenous vein long grafts was 90% at 3 years. The secondary patency rate at 3 years for short grafts was 81% and the limb salvage rate was 80%. There were four amputations with patent grafts. Primary and secondary patency rates of jump grafts were similar (53%), whereas the limb salvage rate was 89% at 2 years. Patency and limb salvage rates of rarely employed nonautogenous conduits were less than 35% at 1 year (long grafts). Bypass grafts to the ankle and foot are effective and durable and should be performed with autogenous vein.

Aged↗
PubMed1987

Iliofemoral venous obstruction without thrombosis.

Nonthrombotic iliofemoral venous obstruction, masquerading as deep vein thrombosis, was diagnosed in four patients. In each instance the patient was hospitalized and intravenous heparin therapy was started. Phlebography demonstrated venous outflow obstruction without thrombosis; subsequent CT scanning revealed an obstructing lesion in each case. At surgical exploration, (1) endoaneurysmorrhaphy of a hypogastric artery aneurysm decompressed an obstructed right iliac vein; (2) a primary iliac vein leiomyosarcoma was extirpated; (3) a synovial cyst arising from the right hip joint, which obstructed the femoral vein, was excised; and, (4) a postherniorrhaphy inflammatory mass obstructing the left iliofemoral vein junction was confirmed with biopsy results. Improved diagnostic accuracy with its attendant specific therapy is achieved in suspected cases of iliofemoral vein thrombosis if, in addition to noninvasive venous studies or phlebography, CT scanning of the abdomen and pelvis is performed.

Adult↗
PubMed1986

Totally autogenous venovenous composite bypass grafts. Salvage of the almost irretrievable extremity.

When a suitable single length of saphenous or arm vein is unavailable, the elderly patient with a profoundly ischemic extremity, poor runoff, and a distal outflow vessel frequently undergoes amputation. Rather than performing primary amputation or resorting to nonautogenous conduites, we used 21 different combinations of available vein segments of ipsilateral or contralateral greater saphenous, lesser saphenous, cephalic, and basilic veins as composite autogenous bypass grafts. Fifty-four extremities, of which 21 (39%) had one or more failed previous bypasses, were revascularized. Tissue necrosis necessitated operation in 74% (40 instances) and rest pain in 19% (ten instances). All grafts extended below the knee, 22% (12 grafts) to the infrageniculate popliteal artery, 78% (42 grafts) to an infrapopliteal runoff vessel, and 28% (15 grafts) to the ankle or foot. The patency rate at one month was 81%. Thrombectomy alone or with local graft repair increased the one-month patency rate to 96%. At one year, the patency and limb salvage rates were 74% and 82%, respectively.

Aged↗
PubMed1986

Malignant melanoma embolus as a cause of acute aortic occlusion: report of a case.

A case of acute aortic occlusion caused by embolization of malignant melanoma tumor fragments is presented. Transfemoral catheter embolectomy restored normal lower extremity circulation. Noncardiac tumor emboli, although rare, originate either from primary pulmonary malignancies or nonpulmonary malignancies with pulmonary metastases and pulmonary vein invasion. Tumor embolization should be considered a possible source of peripheral arterial emboli when there is no other obvious source, such as the fibrillating or infarcted heart. In such cases, early surgical intervention should be considered in preference to therapy with heparin or streptokinase.

Acute Disease↗
PubMed1986

Preoperative noninvasive assessment of arm veins to be used as bypass grafts in the lower extremities.

Preoperative noninvasive imaging of the veins of the upper extremities has been included in the protocol to select an autogenous vein for a distal bypass in the lower extremity. Arm veins are sought as bypass grafts when the saphenous vein is absent or not usable. Duplex ultrasound provided images of the cephalic and basilic veins in 10 patients in whom visual inspection failed to reveal usable grafts. All arm veins implanted were at least 2 mm (range 2 to 6 mm) in internal diameter determined by ultrasound and were, on the average, 2 mm larger when unroofed. This noninvasive technique has decreased the number of fruitless surgical explorations to obtain a suitable arm vein and has increased the use of arm veins by revealing veins previously not anticipated by physical examination, which virtually eliminated the use of nonautogenous conduits in our practice.

Arm↗
PubMed1986

"Closed-open" arterial embolectomy.

Peroperative evaluation of the success of thromboembolectomy is achieved with a technique that employs interrupted horizontal mattress sutures. Angled traction on the sutures functionally closes the transverse arteriotomy while restoration of circulation is assessed. The arteriotomy may be opened for repassing embolectomy catheters by relieving the traction; if circulation is satisfactory the sutures are tied.

Embolism↗
PubMed1986

The transition to "in situ" vein bypass grafts.

In situ saphenous vein bypass grafts were used to revascularize 109 lower extremities in 99 patients during 1984. Of those, 102 were single length grafts carried out in 53 males and 39 females with an average age of 69 and 75 years old, respectively. The expected associated risk factors were observed: smoking in 69 per cent, hypertension in 57 per cent, heart disease in 52 per cent and diabetes in 31 per cent of the patients. Grafts were performed for limb salvage in 71 patients, claudication in 30 and aneurysm in one. Single length grafts originated from the common (47), superficial (27), deep femoral (18) or popliteal (four) arteries or proximal Dacron (polyester) grafts (six); 93 per cent of the grafts were to an infrageniculate target site, while 44 per cent extended to an infrapopliteal artery and 7 per cent to the ankle. Operating time including completion angiography, which was done in every instance, was comparable to that with reversed vein grafts. The patency rate at one year was 96 per cent or 87 per cent when claudication or limb salvage was the indication for operation, and 92 per cent or 86 per cent when the distal anastomosis was to a popliteal or infrapopliteal artery. Limb salvage rates were 97 per cent at one month and 91 per cent at one year. All five amputations occurred in patients receiving infrapopliteal grafts for gangrene. The survival rate was 97 per cent at one month and 85 per cent at one year.

Aged↗
PubMed1986

Arm veins for arterial revascularization of the leg: arteriographic and clinical observations.

The results of 160 infrainguinal bypasses with arm vein grafts were analyzed. Seventy-three arteriograms were reviewed to identify early and late graft defects; arteriographic findings paralleled those described for saphenous vein grafts. Intimal fibrosis during the first postoperative year, observed in 16 grafts, was the most common defect. Aneurysmosis and elongation were rare, resulting in two graft replacements. Patency and limb salvage rates were calculated for 88 single-length femorodistal bypass grafts; the other 72 were inflow (eight) or outflow (22) jump grafts, sequential (eight) and composite autogenous vein grafts (34). The primary and secondary patency rates for single-length grafts were 74% and 80% at 1 year and 51% and 57% at 5 years, respectively. The limb salvage rate at 5 years was 82%. The survival rate for all patients was 44% at 5 years. These findings reconfirm our use of arm veins as bypass grafts when the saphenous vein is unavailable.

Aged↗
PubMed1986

Alternative autogenous vein grafts to the inadequate saphenous vein.

Autogenous veins other than single-length greater saphenous vein were used in 150 operations to revascularize the extremities of 138 patients; three operations were for upper extremity ischemia and four were lower extremity reconstructions with lesser saphenous vein grafts. The remaining 143 bypasses were performed to revascularize lower extremities in 131 patients. Arm vein grafts were used in 102 operations, and 14 different combinations of vein segments were used to construct 41 totally autogenous composite vein grafts. Tissue necrosis or rest pain was the indication for 70% of arm vein bypasses; 52% of these grafts extended to an infrapopliteal artery. The 1-, 3-, and 5-year patency rates were 82%, 69%, and 60%, resulting in limb salvage rates of 93%, 91%, and 81%, respectively. Composite autogenous vein grafts resulted in a 1-year limb salvage rate of 79% in a select group of elderly patients with advanced arterial disease, poor runoff, and profound ischemia. Limb salvage was the indication for 93% of these operations; tissue necrosis was present in 71% while 80% required infrapopliteal reconstructions--37% to a peroneal artery and 29% to the ankle or foot. Successful limb salvage has been accomplished with alternative autogenous veins when the greater saphenous vein is missing or inadequate, dramatically reducing the use of prosthetic conduits in our practice.

Aged↗
PubMed1984

The need for arteriography in diabetic patients with gangrene and palpable foot pulses.

A group of five diabetic patients had gangrene or failed limited amputations and palpable foot pulses in a total of seven limbs. Because a failure to heal persisted and gangrene progressed, arteriography was performed and disclosed occlusion of all three infrapopliteal arteries. Tibial bypass grafting resulted in complete healing in four of the five patients. The fifth patient refused surgery and died with progressive sepsis. The incidence of this unusual syndrome is unknown, but presumably it is rare. The mechanism of pulse formation in the foot, despite occlusion of the infrapopliteal vessels, is dependent on good flow to the popliteal artery, collateral flow to the rigid distal tibial-peroneal vessels, compliant ankle arteries, and highly resistive distal foot vessels. Although healing of limited amputations is usual in diabetic patients with foot pulses, it is not universal. We recommend that arteriography be performed routinely if gangrene is present and the foot is salvageable, irrespective of pedal pulse status.

Aged↗
PubMed1984

Large-vessel arterial occlusive disease in symptomatic upper extremity.

Subclavian and axillary artery occlusive disease resulted in sufficient upper extremity symptoms to necessitate 30 vascular reconstructions in 28 patients over the past ten years. Female patients predominated, with a ratio of 2.5:1. The average age of the patients was 61 years. The incidence of diabetes mellitus was low (7%). Sixteen of 18 proximal subclavian lesions were on the left side, while more distal lesions were equally distributed on the left and right. Extrathoracic bypasses were used in all cases. Dacron grafts were used in 16 of 17 carotid-subclavian bypasses. Autogenous vein grafts were used in 11 of 13 bypasses to the axillary or brachial artery. Concomitant cervicodorsal sympathectomy was done in only four patients. The in-hospital graft patency rate was 93% and the long-term graft patency rate at one year and beyond was 88%.

Adult↗