Gerald M. Baur

Treatment of chronic visceral ischemia

Herein, we have described the surgical management of 23 patients with chronic intestinal ischemia. The patients presented most commonly with postprandial pain and weight loss. Diagnosis was confirmed by angiography, including lateral aortography. Surgery included bypass with Dacron being the most common graft material. As many vessels as possible were revascularized using an infrarenal graft origin. Two patients died postoperatively from acute myocardial infarction. There were two graft failures in this group. At the present time, 19 of the 21 surviving patients are asymptomatic or greatly improved.

Antigenicity of venous allografts.

With isolated exceptions, the clinical use of venous allografts has been disappointing. Considerable evidence indicates that allograft antigenicity plays a major role in the failure of venous allografts when used as arterial replacements. Recent reports suggest that DMSO-cryopreservation of venous allografts may reduce allograft antigenicity while preserving allograft viability. The present study examines the effect of modifications of vein allografts on subsequent allograft antigenicity. Skin grafts were transplanted from ACI to Lewis inbred strains of male rats. Primary skin graft rejection occurred in 9.0 ± 1.0 days. Subcutaneous implantation of fresh inferior vena cava from ACI rate into Lewis rats resulted in subsequent skin graft rejection in 5.0 ± 1.0 days, confirming the antigenicity of venous tissue. Cryopreservation of ACI inferior vena cava for seven days prior to implantation, with or without 15% DMSO, resulted in subsequent skin graft rejection in 5.0 ± 1.0 days. Treatment of ACI inferior vena cava with 0.30% gluteralde-hyde for 20 minutes prior to implantation in Lewis rats resulted in skin graft rejection in 9.0 ± 1.0 days, the same time as a first set rejection. This study indicates that unmodified veins are normally antigenic and that this antigenicity is not eliminated by cryopreservation with or without DMSO. Gluteraldehyde treatment appears to reduce allograft antigenicity, but results in a nonviable graft. At the present time, there is no known way to reduce the antigenicity of viable venous allografts.

Evaluation and management of patients with Raynaud's syndrome☆☆☆

The wide spectrum of associated disorders, the previous lack of understanding of pathogenesis, and the older, arbitrary terminology in relation to ultimate prognosis have led to confusion in the evaluation and management of Raynauds syndrome. A unified concept of pathogenesis, in which vasospasm and arterial occlusive disease are the fundamental lesions, is presented herein. The associated disorders found in our 219 patients with continuous follow-up are listed and related to the underlying pathogenetic mechanisms. Our approach to diagnosis led to the discovery of an associated condition in 71 percent of our patients. The evaluation can be done in a cost-effective manner. The emphasis of treatment should be on conservative medical management, with avoidance of cold and tobacco and judicious use of pharmacologic agents remaining the cornerstones of therapy. Cervicothoracic sympathectomy has no role in the treatment of Raynauds syndrome.

Fresh and cryopreserved venous allografts in genetically characterized dogs

The autogenous saphenous vein is universally accepted as the conduit of choice for arterial bypass procedures in small vessels. Unfortunately, 2030% [S] of patients do not possess an adequate saphenous vein because of previous vein stripping, thrombophlebitis, or venous anomalies. Abundant laboratory and clinical research to date has failed to produce a uniformly successful prosthetic graft for small vessel application, although modest progress has been made in recent years. Attention has inevitably turned to the possible use of venous allografts in those patients requiring small vessel bypass procedures who do not possess an adequate saphenous vein. Considerable investigative and clinical data have been accumulated on the use of venous allografts in arterial surgery since the beginning of this century. With several isolated exceptions [21, 221, the use of venous allografts in patients has been disappointing to data. Many investigatars, however, feel the venous allograft may have a role in future arterial surgery if the allograft can either be antigenically modified prior to implantation or if the immunologic reactivity of the host can be modified. A recent important paper by Weber ef al. [24] indicated a marked improvement in the function of venous allografts following cryo-

Percutaneous angiographic embolization: A procedure of increasing usefulness: Review of a decade of experience***

During the past decade percutaneous therapeutic vascular occlusion was performed on 152 occasions in 124 patients. The primary indication for vasoocclusive therapy was acute or recurrent bleeding. Upper gastrointestinal bleeding from arterial sources was controlled in 92 percent of patients and acute variceal bleeding in 83 percent. Renal embolization was performed for palliation of severe pain and hematuria from unresectable renal primary or secondary malignancies, to decrease blood loss and facilitate surgery in operable renal tumors, and for ablation of renal function to control chronic protein loss or severe hypertension. Our encouraging experience convinces us that transcatheter embolization is a useful, safe and effective procedure in selected patients. It seems certain that the technique of therapeutic embolization will be improved, its indications extended and its application become commonplace whenever angiographic skills and facilities exist.

Finger gangrene caused by small artery occlusive disease.

Available evidence indicates that about one third of all patients presenting with localized finger gangrene develop the condition due to intrinsic occlusions of the small arteries of the hand and fingers caused by one of a variety of systemic diseases. We have treated 35 such patients in the past seven years. A variety of diagnostic tests allowed the establishment of the diagnosis of connective tissue disease in 14 patients, hypersensitivity angiitis in 13 patients, arteriosclerosis in five patients, and in yd o id metaplasia, calciphylaxis, and carcinoma in one patient each. Treatment with cold and tobacco avoidance, vasodilators, and local debridement produced good results without amputation in 30 patients. Five patients required partial phalangeal amputation. These results suggest that appropriate diagnostic tests will allow an accurate diagnosis in all patients, and that the natural history is that of spontaneous improvement without major tissue loss. In our experience, surgical sympathectomy plays no role in the treatment of these patients.

The role of arteriography in abdominal aortic aneurysm

The results of arteriography in the management of 100 consecutive patients with abdominal aortic aneurysms are presented. Arteriographic information had substantial influence upon management decisions and performance of surgery in 75 per cent of cases. We found the preoperative knowledge of the precise vascular pathology or anatomic variants not only permitted a more rational recommendation for or against surgery but aided in the selection of the most suitable surgical procedure.

Arm ischemia secondary to giant cell arteritis

Six cases of arterial insufficiency of the arm secondary to giant cell arteritis are described, all in elderly white women. The clinical presentation of the occlusive disease ranged from an asymptomatic incidental physical finding to an alarming picture of severe ischemia. All patients were treated with steroids and had subsequent stabilization or improvement of extremity symptoms. Vascular reconstruction was also performed in two patients, one of whom developed rest pain after graft occlusion. Another patient had a cerebral infarction while taking prednisone, despite control of large vessel vasculitis. This study indicates that giant cell arteritis should be considered in cases of occlusive disease of the arms, especially in elderly women. Giant cell arteritis is a seriously morbid and potentially fatal disease which justifies a thorough evaluation when sufficient evidence is present to suggest the diagnosis. The response to steroids is usually adequate to eliminate the need for early surgical intervention.

Intraarterial streptokinase infusion for acute popliteal and tibial artery occlusion

Eight consecutive patients with acute thrombotic or embolic occlusion of the popliteal or tibial artery were treated with low-dose intraarterial streptokinase followed by arterial reconstructive surgery where appropriate. Three patients had acute thrombosis of a popliteal aneurysm with limb-threatening ischemia. All three were relieved of their acute ischemia by streptokinase infusion accompanied by lysis of clots in the popliteal artery outflow tract. Each patient then underwent elective popliteal aneurysm bypass. Four patients had acute embolic popliteal or tibial artery occlusion. Each was relieved of ischemic symptoms. One required surgery to remove residual clot. One patient with thrombosis of the tibioperoneal trunk did not have a decrease in symptoms with streptokinase infusion, but did experience sufficient outflow tract thrombolysis to permit construction of a tibial bypass with resultant restoration of normal circulation. Low-dose intraarterial streptokinase may be the treatment of choice for selected patients who present with thrombosis of a popliteal aneurysm with tibial vessel involvement or with embolic popliteal or tibial artery occlusion.

Blood flow in the common femoral artery: Evaluation in a vascular laboratory☆

Accurate knowledge of the hemodynamics of the common femoral artery is a critical part of both the preoperative evaluation of patients with peripheral vascular disease and the postoperative follow-up examination. Interrogation of the iliofemoral system with determinations of palpable pulse status, Doppler analog waveforms, and upper thigh pressure ratios has yielded an overall sensitivity of 91 percent and a specificity of 85 percent in the detection of inflow stenosis. This degree of accuracy (89 percent) allows practical surgical decisions to be based on the results of these noninvasive studies.