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P Polterauer

Publications and source records attributed to P Polterauer.

At least 73 records · Page 4Linked to original sources
PubMed1993

Anticoagulants, antiaggregants or nothing following carotid endarterectomy?

Carotid endarterectomy (TEA) has proven to be beneficial for symptomatic patients. Anticoagulation (AC) and antiplatelet therapy (ASA) have been shown to prolong life following vascular surgery in patients with occlusive arterial disease (PAOD). To determine whether ASA or AC prolong life after TEA, retrospective analysis was undertaken, since cerebral haemorrhage is associated with the use of both drugs, especially AC. Between 1979-1986, 328 patients with stenotic lesions of the carotid bifurcation were operated upon electively. Patient survival and causes of death were the primary end points of the analysis. Recent data were obtained from the Austrian Central Bureau of Statistics. Cumulative survival rates were calculated by Kaplan-Meier estimation and differences determined by Breslow and Mantel tests. 36 patients were on AC, 157 on ASA and 135 remained without medication (0-group). Since the common risk factors in PAOD were unevenly distributed between groups, a stepwise Cox regression model was applied which revealed age (p < 0.01), cardiac pathology (p < 0.01) and diabetes (p < 0.05) as relevant for survival. Therefore, ASA patients and 0-group patients were selected and matched, employing the aforementioned prognostic criteria, and compared to the patients on long-term AC for various indications (vein bypass surgery, myocardial infarction, pulmonary embolism; i.e. data-matching). The median postoperative survival was 7.72 years for ASA and 8.48 years for AC, compared to 6.07 years for the 0-group (p = 0.0095 Breslow, p = 0.477 Mantel). There was no significant difference between AC and ASA treated patients. Irrespective of medication, the causes of death were well balanced, and no higher incidence of intracerebral haemorrhage was detected.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1992

Dacron versus polytetrafluoroethylene for Y-aortic bifurcation grafts: a six-year prospective, randomized trial.

BACKGROUND: A prospective, randomized trial was conducted to compare Dacron with expanded polytetrafluoroethylene (ePTFE) in reconstructive aortoiliac surgery. No comparable trial with a prospective, randomized design with a comparable number of patients or an equal long-term follow-up period can be found in the literature. METHODS: Between 1984 and 1989, 165 patients were randomized for either Dacron or ePTFE on the basis of age, sex, indication for surgery, diabetes, nicotine consumption, runoff, and operative approach. The two groups were well matched for randomization criteria, as well as the incidence of aneurysms. RESULTS: No statistically significant difference was found between the two graft materials in terms of patency rates (corrected 3-year patency rates: Dacron = 95% vs ePTFE = 95%; Breslow, p = 0.83; Mantel-Cox, p = 0.74). Subgroup analysis comparing long-term patency rates of the two graft materials and relating them to poor runoff, good runoff, aneurysms, and arterial occlusive disease also failed to show any significant differences between ePTFE and Dacron. Early graft failure (n = 6; 3.6% of the patient population; p = 0.045) and severe abdominal graft infection (n = 3; 1.8% of the total population) were seen only in ePTFE grafts. However, these did not affect the corrected long-term patency rate of ePTFE grafts. There were five late graft failures with PTFE (3.0%) and four with Dacron (2.4%). CONCLUSIONS: Graft materials currently available for aortoiliac repair were comparable in terms of corrected long-term patency rates. The alleged advantages of PTFE were not confirmed by our data. PTFE grafts were associated with a higher rate of complications, and more redo operations were required to duplicate the results obtained with Dacron.

Aorta↗
PubMed1991

Extra-anatomic femoro-femoral crossover bypass (FF) vs. unilateral orthotopic ilio-femoral bypass (IF): an attempt to compare results based on data matching.

Some surgeons feel that femoro-femoral suprapubic crossover bypass (FF) is the treatment of choice in unilateral artery disease, whereas others reserve this procedure for the rare high risk patient. Results and their evaluation seem to differ depending upon the indications and the patients elected for comparison. We analysed 57 consecutive patients, who received a FF-PTFE graft between 1977 and 1989 (age 48-95 years; male/female 47/10; preoperative clinical status [Fontaine Classification] St. II: 19%, St. III: 58%, St. IV: 23%; diabetics: 14; smokers: 40). The estimated cumulative primary and secondary patency according to the Kaplan-Meier method were 52 +/- 10% (three grafts at risk) and 63 +/- 10% (six grafts at risk), respectively at 5 years. There was no statistical difference in the secondary patency comparing patients with a good and bad run-off (Breslow, Mantel-Cox). The cumulative 5-year survival was 35 +/- 7% (nine patients at risk). The results were compared with those obtained in a group of 150 patients, in whom an unilateral ilio-femoral (IF) retroperitoneal orthotopic graft had been implanted for the same indication and within the same period. Comparing the primary patency of FF and IF patients (55 +/- 6%; 24 grafts at risk) no significant difference could be seen at 5 years. But there was a significant difference in the 5-year survival rates, being in favour of the IF-group (43 +/- 5%; 43 patients at risk) suggesting that both groups were not comparable.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1991

[The status of carotid artery surgery today: technique, indications, results].

Carotid artery endarterectomy (CAE) is a surgical standard procedure today. The indication is the symptomatic patient (Stage II) with transient ischemic attacks (TIA) and stenosis of the internal carotid artery (ACI). Data of several studies have yielded a highly restrictive policy toward operative procedures in asymptomatic patients (Stage I) with carotid bruit or ACI-stenosis. Furthermore there emerged wide consensus, that patients with frank stroke (Stage III) should not be operated upon. As diagnostic procedures highly advanced non invasive procedures came up during the last decade, as well as computerized tomography and digital subtraction angiography. The operative procedure is performed in general anesthesia with controlled hypertension during the clamping period (n = 650). Perioperative results without using a shunt are not different to those with a shunt. During the last 5 year period our results yielded a 1% perioperative central permanent neurological deficit rate (CPNDR) and a 1% operative mortality. During a 51 months median observation period 1.5% presented again with transient ischemic attacks-with TIA; 0.6% developed a stroke and 2.2% deceased by cerebral complications yielding at totally 4.3% long term complication rate. The annual rates are 0.3%, 0.1% respectively 0.5%, totally 0.9%. In conclusion CAE can be offered as a safe surgical stroke preventing procedure in symptomatic TIA patients with ACI stenoses in our institution. Perioperative as well as long term results are yielding a high standard and are clearly better than those without operation.

Carotid Artery Diseases↗
PubMed1991

[Effect of postoperative aggregation inhibiting therapy following carotid thrombendarterectomy on patient survival. Analysis after more than 15 years follow-up].

The patients in the clinical series as well as in the group with preoperative known cardiac risk receiving postoperative ASA medication yielded a significant better long-term survival results. ASA prolongs long-term survival after carotid endarterectomy. A postoperative ASA-therapy decreases the incidence of lethal cardiac complications.

Aspirin↗
PubMed1991

[Acetylsalicylic acid after iliac-femoro-popliteal interventions?].

To determine whether acetyl salicylic acid (ASA) in a daily dose of 1500 mg versus untreated controls is effective in patients with peripheral arterial disease a prospective randomized but not placebo-controlled one single centre trial was undertaken. Patients were assigned to one of two groups by means of multi-dimensional contingency tables whereas the risk factors age, sex, height, body weight, diabetic metabolic state, hypertension, history of myocardial infarction, smoking habits and preoperative clinical status according to the Fontaine classification where found in the state of balance. 298 patients with arterial occlusions in the iliaco-femoro-popliteal level were recruited during 1971-1974, the primary end points were probability of patency and probability of survival. In regard as well as to the probability of patency (p less than 0.56 Breslow, p less than 0.66 Mantel) as to the probability of survival (p less than 0.10 Breslow, p less than 0.70 Mantel) no statistical significant difference was detected. In conclusion ASA, in the doses administered here, was unable to improve patency or prolong patient survival, an outcome, which is at variance with results obtained by others.

Arterial Occlusive Diseases↗
PubMed1990

Antiplatelet therapy following carotid bifurcation endarterectomy. Evaluation of a controlled clinical trial. Prognostic significance of histologic plaque examination on behalf of survival.

To determine whether antiplatelet therapy following carotid bifurcation endarterectomy influences postoperative survival and whether signs of progression in the plaques harvested at the time of surgery might be a prognostic indicator, a controlled clinical trial was undertaken. During 1982 to 1985, 66 patients were recruited, operated on (carotid endarterectomy) and assigned, using the method of adaptive randomisation to the therapy group (n = 32) receiving 1.0 g acetylsalicylic acid (ASA) per day, starting day two prior to surgery, or to the control group (n = 34), which remained without antiplatelet medication. The plaques harvested at the time of surgery were processed using standard histopathological methods and examined "blindly" by light microscopy for signs of arterio-sclerotic progression. The final endpoint was patient survival. The last assessment of the participants survival status was done by June 1989. During follow-up, 20 patients died, six in the treatment group and 14 in the untreated group, the difference being statistically significant (P less than 0.013 Breslow, P less than 0.029 Mantel). In 27 instances the histo-pathological examination showed signs of progression. In this subgroup ASA yielded a significant prolongation of patient survival (P less than 0.017 Breslow, P less than 0.048 Mantel). In the remaining patients no signs of cellular infiltration were evident and no influence of ASA on patient survival was demonstrable (P less than 0.503 Breslow, P less than 0.390 Mantel).

Aged↗
PubMed1990

Antiplatelet treatment prolongs survival after carotid bifurcation endarterectomy. Analysis of the clinical series followed by a controlled trial.

To examine the role of antiplatelet drugs in the secondary prevention of arteriosclerotic arterial disease following carotid endarterectomy, a clinical series (n = 252) was analyzed. Based on these results a prospective randomized trial was initiated, comparing the effect of antiplatelet drugs (acetyl-salicylic acid [ASA] 1000 mg/day) versus untreated controls. In both investigations patient survival was the primary end point. A cardiac risk (n = 91) implied a significant reduction in patient survival (p less than 0.019 Breslow, p less than 0.052 Mantel). Antiaggregating drugs prolonged survival in the collective series (p less than 0.0001 Breslow, p less than 0.0002 Mantel) and in the subgroup of patients with cardiac risk (p less than 0.014 Breslow, p less than 0.020 Mantel) as well. In the prospective trial 66 patients were recruited, receiving ASA (n = 32) versus no therapy (n = 34). During follow-up 15 patients died, 4 in the treatment, and 11 in the control group. Between both groups there was a significant difference in the probability of survival (p less than 0.021 Breslow, p less than 0.048 Mantel).

Aspirin↗
PubMed1990

Patency rate of implantable devices during long-term intraarterial chemotherapy.

Intraarterial implantable drug delivery systems have been considered as an alternative method for treating patients with unresectable liver malignancies. However, catheter problems with external implanted devices have resulted in limited application of chemotherapy. The introduction of subcutaneous devices offers an opportunity for long-term locoregional chemotherapy. Twelve external intraarterial catheters were implanted into 12 patients and 52 subcutaneously placed devices into 51 patients, all with various hepatic malignancies. Retrospective analyses comparing those two intraarterial systems were conducted taking into account the function and complication rate (hepatic artery thrombosis, infection, leaking, hemorrhage, and dislocation). The follow-up time for the external system was two to eight months (median five weeks), the thrombosis rate 33.3%, and the infection rate 25%. One instance of severe bleeding from the hepatic artery occurred during chemotherapy. One catheter dislocated. For the subcutaneously implanted intraarterial devices the follow-up time was five to forty-one months (median sixteen months), the thrombotic complication rate 17.3%, and the infection rate 7.6% (all patients with simultaneous bowel surgery). Catheter dislocation one year later required reimplantation; in 1 patient therapy had to be discontinued because of a catheter leak. The overall function rate was 71.3% with a median follow-up time of eight months. Anticoagulation therapy for subcutaneously implanted devices starting from the beginning of intraarterial chemotherapy is recommended to achieve long-term patency. No implantation should be preformed simultaneously with bowel surgery. The subcutaneously placed intraarterial devices had a higher function rate and were available for a longer period as compared with external implanted catheters.

Equipment Failure↗
PubMed1990

Intraatrial extension of thyroid cancer: technique and results of a radical surgical approach.

An occlusion of the superior vena cava by a tumor thrombus extending into the right atrium was diagnosed in three patients with a follicular thyroid cancer. All patients showed the typical clinical picture of the superior vena cava syndrome. A right parasternal thoracotomy was performed for preparation of the major vessels. The superior vena cava was opened and the entire intravascular tumor thrombus was removed. The cavotomy was closed directly in two patients. In the third patient the left brachiocephalic trunk was resected and reconstructed with a vascular (polytetrafluoroethylene) graft. This patient had bone and brain metastases and an occlusion of the graft 3 months after surgery after anticoagulation was stopped. The other two patients were clinically symptom free without local recurrence 13 and 50 months after surgery. An aggressive surgical approach is justified in grossly invasive thyroid cancer to decrease local recurrence and death rates, to correct the disturbing clinical symptoms of superior vena caval occlusion, and to prevent tumor embolism and the development of distant metastases. By reducing tumor mass, an even better basis for radioiodine treatment can be prepared.

Adenocarcinoma↗
PubMed1989

Groin infections following vascular surgery: obturator bypass (BYP) versus "biologic coverage" (TRP)--a comparative analysis.

Deep infections in the groin complicating vascular surgical procedures pose a serious problem, in the treatment of which two alternative methods are available: (1) Removal of the graft and the construction of an extra anatomic bypass (obturator canal bypass, BYP), or (2) retaining the graft and achieving healing of the infected wound by various biological materials, such as omentum or an inferior rectus abdominis muscle flap (TRP). The probability of patient and limb survival was estimated by the Kaplan-Meier method and possible differences between both groups checked using Breslow's and Mantel's tests. No statistically significant differences were found and a variety of factors with potential influence on the outcome were considered equally balanced. However, as soon as the catastrophic event of infection plus haemorrhage enforced emergency surgery, the incidence of success differed markedly: in the BYP group 6 infections healed out of 8 and in the TRP group 1 out of 6.

Adult↗