Analysis of 274 Omniflow Vascular Prostheses implanted over an eight-year period.

BACKGROUND: Polytetrafluoroethylene (PTFE), dacron, and, more recently, collagen prostheses are finding increasing use for femoropopliteal reconstruction when a suitable vein is not available. The main factors to be considered when choosing a prosthesis are patency, susceptibility to infection and formation of aneurysms. METHODS: Sheep collagen prostheses were implanted on 274 occasions in the femoropopliteal or crural regions. RESULTS: The patency rate for supragenual bypass after 3 years was 61.9% with good vascular periphery and 44% with poor vascular periphery. If the prosthesis extended below the knee, the patency rate was 55.4% with good and 35.3% with unfavourable vascular periphery. Patency for the femorocrural bypass was 28.7% after 2 years. The rate of infection was 0% and an aneurysm occurred in three patients (1.1%). CONCLUSIONS: With this low infection rate and very slight danger of aneurysm, the long-term results suggest that the ovine collagen prosthesis can be recommended for use when no suitable vein is available.

[Results of surgical treatment of pregnancy-associated pelvic vein thrombosis]. / Ergebnisse der chirurgischen Behandlung der schwangerschaftsassoziierten Beckenvenenthrombose.

We report the results of surgical treatment of iliofemoral vein thrombosis in 49 pregnant women in a seven years period. The patients mean age was 26.5 years (range 18-41 years). Isolated descending pelvic vein thrombosis (PVT) occurred between the 20th and 36th week of pregnancy and was located predominantly left sided. 89.8% of PVT developed in the late period of gestation, three cases of pelvic vein thrombosis were diagnosed after vaginal delivery. An iliac vein spur in one patient and an AT-III deficiency in two cases were registered as additional risk factors. After venous catheter thrombectomy an arteriovenous fistula between the superficial femoral artery and the femoral vein was performed to increase blood flow and velocity in the pelvic veins. Abdominal delivery was performed simultaneously, if thrombosis occurred after the 34th week of pregnancy. Late re-thrombosis was registered in 4 patients (9.0%) after a mean follow-up of 42 months. We have seen symptoms of mild, not life threatening pulmonary embolism in two patients on the first postoperative day (complication rate 4.0%). Re-occlusion rate was high (3/5) after surgical thrombectomy carried out between the 20th and 26th week of gestation. Risk factors were an AT III deficiency in two cases and the continued compression syndrome of the pelvic veins caused by the enlarging uterus. In the late period of gestation surgical thrombectomy of PVT is the preferential method of treatment in selected patients with good therapeutical results. The operation reduces the risk of future venous insufficiency and post-thrombotic syndrome in the young female patients.

Paragangliomas of the carotid bifurcation: oncological aspects of vascular surgery.

The present study reviews in concise form the past 12 years of our clinical experience with paragangliomas of the carotid body. Every aspect of the anatomical, histological and biological and biological behaviour of paragangliomas of the carotid body has been recorded in order to be able to define better surgical management and the clinical prognosis. In addition to the conventional histological methods of investigation we also applied immunohistochemistry and made use of electron microscopy. Eighteen tumours of the carotid body in 12 female and four male patients with a mean age of 54 years (34 to 70 years) were treated surgically. Angiography of the aortic arch and supra-aortic branches was undertaken diagnostically in every case. In three patients computer tomography and magnetic resonance imaging demonstrated spreading of the tumour up to the base of the skull and pre-operative embolization of the arteries supplying the tumour was performed to decrease tumour vascularity. In four cases (22%) resection of the internal carotid artery and its reconstruction by a saphenous vein graft was required in order to achieve the therapeutic aim of a complete extirpation of tumourous tissue and preserving the vascular system of the internal carotid artery. In three cases (16%) there was histological evidence of a metastasizing process to the local lymph nodes of the neck and, due to this criterion of malignancy, 50-60 Gy of radiation was applied to the site of the tumour after surgery. Four patients experienced a transient neurological deficit in the supply area of the hypoglossal and the recurrent nerves. In one case, the vagus nerve could not be retained. In an average follow-up of 102 months we recorded one case of local recurrence 13 months after the initial resection and radiation treatment applied to a malignant paraganglioma. All the other patients were doing well without evidence of recurrent disease.

[Femoropopliteal vascular replacement: vein, ePTFE or ovine collagen?]. / Zur Problematik des femoropoplitealen Gefässersatzes: Vene, ePTFE oder ovines Kollagen?

In an eight year-period from 1988 to 1995 653 femoropopliteal and femorocrural bypasses were performed. 347 above-knee reconstructions 206 below-knee reconstructions and at last 100 femorocrural bypasses were analysed. The cumulative patency rate after a follow up of three years for above-knee vein bypasses was 90%, patency rate for PTFE grafts in the same period was 52%, for ovine collagen grafts 56%. For below-knee bypasses with autologous saphenous vein a function rate of 76% could be observed in the same period, the rate of PTFE grafts in this position was only 30%. In this position 3-year patency rates of 50% were achieved with ovine collagen grafts. This difference was statistically significant. Three years cumulative patency rate for femorocrural reconstructions with greater saphenous vein was 72%, the function rate for PTFE in this position was below 30% after a follow up of one year, with ovine grafts below 40%. Graft infection, aneurysm formation and postoperative mortality were low in all groups. Our data demonstrate, that patency rates of autologous vein bypasses could not be achieved with PTFE or ovine collagen prosthesis in any femoropopliteal the femorocrural position. We therefore cannot confirm the recommendation to use alloplastic grafts as primary choice for above knee bypasses to spare the saphenous vein.

[Indications and outcome of simultaneous operation of carotid stenoses and stenosing coronary arteriosclerosis]. / Indikation und Ergebnisse der Simultanoperation von Carotisstenosen und stenosierender Koronarsklerose.

Between 1986 and September 1995 100 patients with carotid artery stenosis and coronary artery disease underwent combined carotid endarterectomy and CABG. The indications for carotid endarterctomy were transient neurological events in 38 patients and in 62 cases high-grade asymptomatic carotid artery stenosis. The surgical procedures were always performed by a vascular and a cardiac surgical team. In all cases carotid endarterectomy was performed prior to CABG, 3 patients died during the in-hospital-postoperative period: 2 patients died on the first day after surgery because of cardiac failure, 1 on the 18th day because of pneumonia. 2 patients had postoperative transient neurological events. The results are similar to those of isolated single procedures. Thus combined surgery for severe carotid and coronary artery disease can be performed with low mortality and morbidity.

Diagnosis and treatment of carotid body tumors.

Carotid body tumors are rare although they must always remain part of the differential diagnosis of a neck mass. Sonography as the screening method of choice followed by angiography determines the diagnosis. In 11 patients 12 carotid body tumors were extirpated. The reconstruction of the internal carotid artery with an interposition of the greater saphenous vein was necessary in two cases after resection of the tumor. One patient underwent preoperative embolisation because of a huge tumor. Two postoperative radiotherapies were undertaken because of malignancy in one case and a partially extirpated tumor in the other. After a 9 year follow-up period all patients are alive. One patient suffers from a persistent palsy of the hypoglossal nerve and another complains of permanent headache supposedly caused by the reocclusion of the venous interposition of the carotid artery. In conclusion, our data support the diagnostic strategies in patients with suspected carotid body tumors. Regarding the exact therapeutic regimen, we suggest the surgical resection, followed by radiotherapy in cases of confirmed malignancy or partially resectable lesions.

[Jugulotympanic paraganglioma]. / Jugulo-tympanisches Paragangliom.

A case is described of a jugulotympanic paraganglioma in a 64-year-old woman with extentions down the jugular vein to the clavicle and penetration of the cerebellar fossa. The symptoms, differential diagnosis, therapy and prognosis are discussed on the basis of this case report and compared with the literature. The importance of radiological investigation (e.g. selective angiography and computed tomography) in respect to diagnosis and determination of tumour size is emphasized. The diagnostic value of the immunohistochemical detection of neuron-specific enolase, a neuroendocrine cell marker and S-100 protein is stressed. The most favourable therapy, depending on tumour extension, seems to comprise preoperative embolisation, radical resection and postoperative radiotherapy.

[Iatrogenic vascular injuries in childhood]. / Iatrogene Gefässverletzungen im Kindesalter.

From 1973 until 1982, 616 arterial angiographies were done in children. 13 thromboses in the early state could be diagnosed and were treated surgically. Five times a haemorrhage after angiography made surgical intervention necessary. During the performance of a venesection there was an injury of the brachial artery three times. Two intraoperative iatrogenic vascular injuries were also reconstructed primarily. In the late stage three occlusions of the femoral artery and the distal external iliac artery were reconstructed. A decrease in the growth of the extremity could be seen in these cases. In this respect we want to emphasize the importance of an early diagnosis to prevent late complications.

[Surgical treatment of acute pelvic vein thrombosis]. / Die chirurgische Behandlung der akuten Beckenvenenthrombose.

From 1974 to 1980 77 patients underwent thrombectomy for thrombosis of their iliac or leg veins. 45 patients became symptom-free. The mean age of the patients (mostly females) came up to 43 years, the oldest was 82, the youngest 13 years of age. Following these operations in 20 cases a postthrombectomy-syndrome developed. Only in one case an amputation due to venous gangrene had to be performed. In 28 cases a protective a-v-shunt was installed. 15 times a recurrent thrombosis occurred. 5 of these patients could be reoperated successfully.

[Displacement of electrodes in pacemaker patients (author's transl)]. / Die chirurgische Therapie nach Schrittmacherelektrodendislokation.

The implantation of special electrodes is indicated by right ventricular dilatation and especially by electrode displacement. For this purpose the MIP 2000 has been used with good results. It is the electrode preferred currently, but it may be replaced in future by the screw electrode which is now being clinically tested. Because of the danger of uncontrolled ventricular perforation the indication for operative myocardial implantation of pacemaker electrodes should be restricted especially in cases of myogenic dilatation of the heart.