Biomedical subjects

R Koppensteiner

Publications and source records attributed to R Koppensteiner.

At least 37 records · Page 2Linked to original sources

PubMed1999

[Endovascular treatment of the abdominal aortic aneurysm: assessment, implantation technique, after-care and results].

BACKGROUND: Endovascular treatment of abdominal aortic aneurysm (AAA) is a new minimally invasive alternative to surgical repair. Patient selection, perioperative management, the procedure itself and postoperative follow-up are new aspects. PATIENTS: From June 1997 to June 1998, 37/70 patients (53%) with AAA were treated by the endovascular method. There were 35 males and two females, mean age 74 +/- 7 years, with a mean ASA class of 3.5 +/- 0.5. Graft repair was performed in 33 patients, due to inappropriate aortic anatomy for the endovascular technique in 24 and leaking aneurysm in 9. METHODS: Feasibility is based upon computed tomography and angiography. The procedure was performed in the operating room, under general, regional and local anaesthesia in 14, 3 and 20 patients, respectively. 36 bifurcated and one tube endoprosthesis were implanted. An open access on one femoral or iliac artery and, in case of bifurcated prosthesis, usually a percutaneous access (10 Fr) on the other side were performed. Positioning and delivery were monitored under fluoroscopy. RESULTS: All the AAA could be sealed by the endovascular technique. In one patient, an iliac limb was removed surgically because of proximal misplacement, but the procedure was completed by the endovascular technique. Mean operation time was 140 +/- 67 minutes. ICU stay was 1.4 +/- 1.6 days and patients were discharged after 6.5 +/- 3.5 days. Postoperative radiological follow-up showed totally sealed aneurysms in 34/37 patients (91%). In 3 patients a residual perfusion originating from a lumbar artery was observed. In 7/14 patients with AAA diameter > 6 cm and without residual leakage on the control CT scan, aneurysm pulsation remained after endovascular treatment. There was no early or late death after endovascular repair. During the follow-up period of 4 +/- 3 months patients are doing well. One patient needed balloon dilatation of an iliac limb. CONCLUSIONS: Endovascular treatment of AAA is a minimally invasive technique with short recovery time. This technique seems to be particularly advantageous in elderly or severely ill patients. Long-term controls are mandatory to identify potential complications, particularly when residual perfusion or aneurysm pulsation persists.

Aged↗

PubMed1998

Blood rheology in patients with native heart valve disease and after valve replacement.

Patients with heart valve disease have rheologic abnormalities that are more pronounced in double valve disease than in mitral or aortic valve disease; after valve replacement surgery, the degree of rheologic abnormality is more pronounced in patients with mechanical and biological prostheses than in those with homografts and pulmonary autografts. Rheologic abnormalities seen in these patients might be related to the different incidences of thromboembolism in the presence of various valve defects and various types of prostheses.

Adolescent↗

PubMed1998

Color duplex sonography guided stent placement in a stenosis of the superficial femoral artery. A case report.

We report the first case of a successful stent placement under color coded ultrasound guidance alone in the superficial femoral artery of a 73-year-old woman suffering from intermittent calf claudication following restenosis after an uncomplicated angioplasty five months previously. Because of a hemodynamically residual stenosis after three attempts at dilatation, a percutaneous transluminal angioplasty and stent insertion were performed under the sole guidance of color coded ultrasound. The intervention was performed without complication and at the six-month follow-up examination, the patient was symptom-free and the stent was morphologically intact and hemodynamically functional. This case shows that successful stent placement under ultrasonic guidance alone, without fluoroscopic control is possible, provided that there is adequate sonographic visualization.

Aged↗

PubMed1997

Thromboembolic complications in a patient with heparin-induced thrombocytopenia (HIT) showing cross-reactivity to a low molecular weight heparin-treatment with Org 10172 (Lomoparan).

Heparin-induced thrombocytopenia is an immuno-mediated life-threatening side effect of heparin therapy which poses difficulties in diagnosis and major therapeutic problems. Heparin must be instantly discontinued. We describe the case of a 60-year-old male patient with type II heparin-induced thrombocytopenia, complicated by progressive deep venous thrombosis and pulmonary embolism. He failed to improve when therapy was continued with a low molecular weight heparin (Fragmin) and high doses of intravenous immunoglobulins were administered. The test for heparin-dependent platelet aggregation was positive for unfractionated heparin and low molecular weight heparin, but negative for the heparinoid Org 10172. During subsequent anticoagulant therapy with Org 10172 for seven days the number of platelets increased rapidly and the patient recovered. Nine months later Org 10172 was used again in this patient for thrombosis prophylaxis without any adverse effects. In patients with heparin-induced thrombocytopenia requiring immediately acting anticoagulant therapy, Org 10172 can be considered as an effective alternative drug to unfractionated and low molecular weight heparins.

Anticoagulants↗

PubMed1997

Ultrasound guided compression therapy in 134 patients with iatrogenic pseudo-aneurysms: advantage of routine duplex ultrasound control of the puncture site following transfemoral catheterization.

BACKGROUND: The following study was designed to evaluate the effectiveness and safety of ultrasound guided compression therapy (UGCT) of iatrogenic postcatheterization pseudo-aneurysms (PA) on the one hand and to justify the usefulness of the routine colour duplex control of the puncture site following transfemoral catheterization, on the other hand. MATERIAL AND METHODS: During the study period 142 patients with (PA) following transfemoral catheterization were identified by means of colour duplex examination Eighty of these 142 patients were identified during a routine colour duplex control of the puncture site the day after PTA/angiography because of peripheral arterial occlusive disease (PAOD) [group A]; the remaining 62 patients with symptomatic groins were referred from other departments [group B]. RESULTS: In 8 patients of group B UGCT was considered to be contra-indicated, they were primarily treated by surgical repair of the PA. A total of 134 patients (group A 80 patients, group B 54 patients) underwent an UGCT. In total the success rate of UGCT was in group A 100% and in group B 78%. 12/54 patients (all group B) with failure of UGCT underwent a secondary surgical repair of the PA. Within group B there was a negative correlation between delay of diagnosis/UGCT and success (p < 0.04), whereas the size of the sheath did not influence the outcome of the UGCT (p = 0.3). CONCLUSION: Our study confirms the effectiveness and safety of UGCT. Routine colour duplex control of the puncture site the day following the removal of the sheath after percutaneous catheterization and UGCT of PAs without delay can increase the success rate of UGCT and minimize the need for surgical repair of PAs.

Adult↗

PubMed1997

Variable platelet response to low-dose ASA and the risk of limb deterioration in patients submitted to peripheral arterial angioplasty.

A group of 100 patients with intermittent claudication (70 male, 30 female), treated with I00 mg ASA per day, were followed over 18 months after elective percutaneous balloon angioplasty. Platelet function was monitored over a period of 12 months by corrected whole blood aggregometry (CWBA). Upon stimulation by arachidonic acid (AA), adenosine diphosphate (ADP) and collagen, CWBA-results were obtained by an electronic acquisition and evaluation system correcting for hematocrit and platelet count of the blood sample. All patients showed a completely inhibited platelet response to AA stimulation. Comparison of the CWBA-results with clinical parameters revealed that reocclusions at the site of angioplasty occurred exclusively in male patients for which CWBA failed to prove an inhibition of aggregation upon both agonists, ADP and collagen, and for these patients the risk of complication is at least 87% higher (p = 0.0093). Only 40% of male patients show the expected effect of ASA on in vitro platelet aggregation at any given point in time and CWBA is capable of predicting those male patients which are at an elevated risk of reocclusion following peripheral angioplasty.

Administration, Oral↗

PubMed1996

Elevated lipoprotein(a) and increased incidence of restenosis after femoropopliteal PTA. Rationale for the higher risk of recurrence in females?

It has been shown that the incidence of recurrent stenosis following successful percutaneous transluminal coronary angioplasty (PTCA) is correlated with serum Lipoprotein(a) [Lp(a)] levels. The aim of the present study was to examine the influence of Lp(a) on restenosis after primary successful femoropopliteal PTA. One hundred and thirty nine consecutive patients with peripheral arterial occlusive disease (PAOD) and successful femoropopliteal PTA were studied. Follow-up included clinical examination and non-invasive laboratory testing (pulse volume recordings, ankle-brachial arterial pressure measurement) in every patient before and after 1, 3, 6 and 12 months following intervention. Duplex sonography was performed 1 year after PTA. Suspicion of restenosis (> or = 50% diameter reduction) was verified by angiography. Lp(a) was determined using ELISA technique (mg/dl). Twelve months after successful PTA no restenosis was found in 82 patients (59%: group A). The one-year recurrence rate of 41% (group B) was due to significant restenosis in 35 patients (25%) and reocclusion in 22 patients (16%). The corresponding mean values +/- S.E.M. for Lp(a) were as follows: group A, 28 +/- 5.3; group B 59 +/- 11 (P < 0.01). Women showed a higher frequency of recurrences (55%) versus men (30%, P < 0.01) also corresponding with a high Lp(a) level (51.8 +/- 8 versus 32.7 +/- 5; P < 0.05). Furthermore Lp(a) aggravated the well known increased risk for recurrence in multiple stenoses or occlusions of > or = 5 cm in length. There were no significant differences between groups A and B with respect to age, diabetes, hyperlipidaemia, obesity and cigarette smoking. The results support the view that Lp(a) is an independent risk factor for recurrence after PTA in the femoropopliteal area. It might also be a causal basis for the higher incidence of recurrences in female PAOD patients.

Aged↗

PubMed1996

Tissue concentration of clindamycin and gentamicin near ischaemic ulcers with transvenous injection in Bier's arterial arrest.

BACKGROUND: In the treatment of patients with inflamed ischaemic ulcers in peripheral arterial occlusive disease, high tissue concentrations of antibiotics (TCA) are important. With local transvenous pressure injection in Biers' arterial arrest (TVA-Bier) higher TCAs are assumed to be obtained but they have not been measured. METHODS: Two groups of 16 patients each with ischaemic foot ulcers were studied. In one group, patients received a mean of 284 (SD 116) mg gentamicin and in the other, 1200 mg clindamycin. The antibiotics were given intravenously, intra-arterially, and by TVA-Bier in a randomised order at intervals of 48 hours. Biopsy samples were taken from the edge of the ulcers 20 minutes and 3 hours after TVA-Bier, and 1 hour and 3 hours after intravenous and intra-arterial injection. At the same times blood samples were taken. FINDINGS: TCAs of gentamicin and clindamycin with TVA-Bier were significantly higher compared with intravenous or intra-arterial injection. Median TCA-enhancing factor of clindamycin achieved by TVA-Bier at 20 min 1 hour was 18.3 and 14.1 versus intravenous and intra-arterial infusion, respectively, and at 3 hours 7.3 and 5.6, respectively. The median TCA-enhancing factor for gentamicin by TVA-Bier versus intravenous and intra-arterial application was, at 1 hour 20 min, 9.4 and 9.7, respectively, and at 3 hours 1.2 and 1.7, respectively. INTERPRETATION: Higher TCAs could be achieved with TVA-Bier than with intravenous or intra-arterial infusion. TCAs were lower when using gentamicin and higher with clindamycin.

Aged↗

PubMed1996

Spontaneous laser doppler flux distribution in ischemic ulcers and the effect of prostanoids: a crossover study comparing the acute action of prostaglandin E1 and iloprost vs saline.

The flux distribution within ischemic ulcers and adjacent skin and its change by prostanoids was investigated using laser Doppler flux scanning. A prostanoid-induced increase in ulcer flux could be a rationale for the improved wound healing. In a single-blind prospective study 18 patients received prostaglandin E1 (PGE1) (333.3 ng/min.), iloprost (41.7 ng/min final dose), and 0.9% saline in a randomized order. The average laser Doppler flux within the ulcer (LFU, x +/- SEM, arbitrary units) or in the adjacent skin (LFS) was evaluated before and 30, 60, 90, and 120 min after prostanoid/saline infusion. LFU increased with PGE1 from 2.30 +/- 0.27 to 3.08 +/- 0.31 (+33.9%; P < 0.001) and with iloprost from 2.37 +/- 0.26 to 3.03 +/- 0.27 (+27.8%; P < 0.001) after 120 min, respectively. Saline did not change LFU significantly: 2.19 +/- 0.18 vs 2.55 +/- 0.26 (+16.4%; P > 0.05). Simultaneously, LFS was not significantly changed when pretreatment values were compared with mean flux at 120 min: PGE1 2.13 +/- 0.27 vs 2.54 +/- 0.34, iloprost 2.03 +/- 0.26 vs 1.94 +/- 0.21, and saline 1.74 +/- 0.27 vs 1.92 +/- 0.30 (P > 0.05, each), respectively. The laser Doppler flux scanning technique might be a tool to study the distribution of laser Doppler flux within ischemic ulcers. This might be useful to study the physiological or pathophysiological control of flux within ischemic ulcers as well as possible therapeutic approaches.

Adult↗

PubMed1996

Impaired hemorheology in patients with postmastectomy lymphedema.

Lymphedema of the arm is one of the most disabling and serious complications of breast cancer. Apart from tumor infiltration or fibrosis of lymphatic pathways, little is known about factors favoring the development of lymphedema. In the present study, we investigated the impact of rheologic parameters, e.g. red cell aggregation (EA) and plasma viscosity (PV), and of capillary morphology and capillary flow in patients with breast cancer with (n = 18) and without (n = 18) lymphedema. Patients with lymphedema showed a significant increase of red cell aggregation (p < 0.001) that indicates a systemic component of lymphedema and might offer a possibility of prevention and therapy of this condition. A hitherto unclassified protein factor favoring red cell aggregation and lymphedema might be postulated.

Aged↗

PubMed1996

A randomized, placebo-controlled, double-blind crossover study of the effect of pentoxifylline on ocular fundus pulsations.

PURPOSE: To estimate the short-term effects of pentoxifylline on ocular blood flow in healthy volunteers. METHODS: In ten healthy subjects, either 200 or 400 mg of pentoxifylline or placebo was administered intravenously over 90 minutes in a randomized, double-blind, placebo-controlled, three-way crossover study design. Noninvasive measurements of blood pressure, pulse rate, flow variables in the radial artery, ocular fundus pulsations, and whole blood viscosity and filterability were performed at baseline and at 30-minute intervals until four hours after the start of drug infusion. Ocular fundus pulsation amplitude, which has been shown to estimate the pulsatile component of the ocular blood flow, was recorded with a laser interferometer in the macula, the optic disk, and a peripheral region. RESULTS: Fundus pulsation amplitude significantly increased after infusion of pentoxifylline, with maximum effect 150 to 180 minutes after the start of the infusion. This effect was dose-dependent and more pronounced in the macula (+17%, P < .001 vs baseline, after 200 mg; and +27%, P < .001 vs baseline, after 400 mg of pentoxifylline) and the peripheral region (+14%, P < .001; and +26%, P < .001) than in the optic disk (+11%, P < .002; and +13%, P < .001). Viscosity but not filterability of whole blood dose-dependently decreased. Peak systolic flow velocity in the radial artery decreased after infusion of 400 mg of pentoxifylline. Blood pressure and pulse rate were unchanged during the observation period. CONCLUSIONS: These findings demonstrate that pentoxifylline increases pulsatile ocular blood flow in healthy volunteers. Our results support the possibility that pentoxifylline could be used therapeutically in several eye diseases, such as diabetic retinopathy.

Adult↗

PubMed1996

Demonstration of cystic adventitial disease by intravascular ultrasound imaging.

In a 34-year-old woman with intermittent calf claudication, cystic adventitial disease of the popliteal artery was demonstrated by intravascular ultrasound imaging. Multiple intramural cystic masses were seen to be compressing the arterial lumen. The diagnoses of cystic adventitial disease was confirmed by surgery. Intravascular ultrasound imaging reliably identifies cystic adventitial disease; its application can be recommended as an alternative to established diagnostic procedures (computed tomography, magnetic resonance imaging) in patients undergoing angiography.

Adult↗

PubMed1996

Blood rheology in emergency medicine.

Emergency conditions are generally associated with changes in blood rheology due to a systemic "acute-phase" reaction occurring within hours of the acute event. The acute-phase reaction includes changes in plasma protein patterns as well as in red cell properties. The deterioration of blood flow properties thus resulting is usually moderate and reversible. On the other hand, there are emergency situations caused or at least seriously aggravated by severe changes in blood rheology: circulatory shock, hyperviscosity syndromes, sickle cell crisis, and preeclampsia. In these conditions, special rheological therapeutic measures have to be taken into consideration.

Acute-Phase Reaction↗

PubMed1996

Changes in blood rheology caused by Crohn's disease.

BACKGROUND: Patients with Crohn's disease (CD) are at increased risk for thromboembolism, and multifocal microvascular infarction has even been suggested as a pathogenetic mechanism in CD. Abnormalities in blood rheology may contribute to the thromboembolism. OBJECTIVES: To assess blood rheology in CD patients. DESIGN: Prospective evaluation of rheological parameters. SETTING: Out-patients at the gastroenterological department of a university hospital. PATIENTS: Thirty-seven patients with inactive CD (Crohn's disease activity index (CDAI) < 150), 31 patients with active CD (CDAI > 150), and 39 control subjects with no CD were included in the study. METHODS: C-reactive protein and orosomucoid were used as serum inflammatory parameters. Fibrinogen, red cell aggregation (low shear, 3/s) and plasma viscosity were used as rheological parameters. RESULTS: Fibrinogen (active CD: median 530 mg/dl (interquartile range 410-630); inactive CD: 377 (316-499); and controls: 246 (220-280)), red cell aggregation (active CD: 9.97 arb. units (8.58-11.77); inactive CD: 9.03 (7.25-10.37); controls: 7.58 (7-8.52)); and plasma viscosity (active CD: 1.82 mPa.s (1.68-1.95); inactive CD: 1.72 (1.65-1.82), controls: 1.61 (1.58-1.64)) were all significantly higher in patients with active and inactive CD than they were in controls. Additionally, fibrinogen was significantly higher in patients with active CD than it was in patients with inactive CD. The rheological parameters correlated with serum inflammatory parameters. CONCLUSION: Changes in blood rheology seem to be associated with inflammatory activity in patients with CD. These changes may be involved in the development of thromboembolism and the pathogenesis of mucosal inflammation, especially in patients with high inflammatory activity.

Adult↗

PubMed1996

Increased serum laminin and angiogenin concentrations in patients with peripheral arterial occlusive disease.

AIM: To measure serum laminin and angiogenin concentrations in patients with peripheral arterial occlusive disease (PAOD) Fontaine stages IIb, III, and IV. METHODS: The study population comprised 38 patients (20 men and 18 women) with stage IV PAOD, 11 patients (six men and five women) with stage III PAOD, 18 patients (10 men and eight women) with stage IIb PAOD, and 23 patients (10 men and 13 women) with deep vein thrombosis. Fifteen normal subjects (matched for risk factors) and 10 patients (five men and five women) without PAOD served as controls. Serum samples were obtained at admission and serum laminin and angiogenin concentrations were measured using an enzyme linked immunosorbent assay. RESULTS: Patients with stage IV PAOD had higher serum laminin (mean +/- SEM; 826 +/- 97 ng/ml) and angiogenin concentrations (467 +/- 26 pg/ml) than normal subjects (laminin: 379 +/- 21 ng/ml; angiogenin: 358 +/- 16 pg/ml) and patients without PAOD (laminin: 277 +/- 34 ng/ml; angiogenin: 406 +/- 25 pg/ml). A significant correlation was found between angiogenin and laminin and between serum laminin and fibrinogen concentrations in patients with stage IV disease. CONCLUSIONS: Raised laminin and angiogenin concentrations may be indicators of endothelial damage caused by reduced vascular perfusion or compensatory revascularisation, or both.

Angiogenesis Inducing Agents↗

PubMed1996

Femoropopliteal artery: initial and 6-month results of color duplex US-guided percutaneous transluminal angioplasty.

PURPOSE: To evaluate color duplex ultrasonographic (US) guidance of percutaneous transluminal angioplasty (PTA) of femoropopliteal artery stenoses and occlusions. MATERIALS AND METHODS: Twenty-four patients (11 women, 13 men; mean age, 65.0 years) with severe claudication, abnormal ankle-arm pressure indexes, and lesions in the superficial femoral or popliteal artery depicted at US underwent balloon PTA with US guidance. US findings were confirmed before and after PTA by means of intravenous digital subtraction angiography. RESULTS: All of 22 segmental stenoses and three of four superficial femoral artery occlusions were successfully treated (in 23 patients). In three cases, a residual stenosis was detected after initial PTA, and PTA was repeated with a larger balloon catheter. Of the 21 patients followed up for 6 months, one had reocclusion and three had hemodynamically significant restenosis. CONCLUSION: Results of PTA with US guidance in short stenoses or occlusions of the femoral or popliteal artery are similar to those of PTA with fluoroscopic control.

Aged↗

PubMed1996

Blood rheology after renal transplantation.

Cardiovascular complications seriously affect posttransplant survival in patients after successful renal transplantation. Abnormalities in blood rheology may contribute to these complications. Therefore, we studied the blood rheology before and during a 1-year observation period after grafting in 9 patients by serial measurements of fibrinogen, red cell aggregation, hematocrit, spontaneous platelet aggregation, and plasma viscosity. Prior to grafting, fibrinogen and red cell aggregation were found to be increased in patients on regular hemodialysis as compared with healthy controls, whereas hematocrit and platelet aggregation were markedly reduced. After successful transplantation, the platelet aggregation progressively rose together with the hematocrit, while fibrinogen and red cell aggregation remained abnormally high. Our findings suggest that abnormal blood rheology in patients with chronic renal failure does not improve in response to successful renal transplantation: fibrinogen and red cell aggregation remain abnormally high; further, the overall blood flow properties are supposed to deteriorate due to the postoperative increase in hematocrit and spontaneous platelet aggregation. Adverse rheological conditions thus resulting may contribute to the increased frequency of vascular events observed in transplanted patients.

Adult↗

PubMed1996

[Leriche syndrome: treatment with local lysis and subsequent percutaneous transluminal angioplasty].

Two cases of Leriche's syndrome treated by local thrombolysis and subsequent percutaneous transluminal angioplasty with or without additional stent implantation are described. The fibrinolytic drugs were applied locally into the occlusions through a Mewissen Infusion Catheter and a Katzen Infusion Wire (initial 2.5 mg rt-PA as bolus followed by Urokinase (50000 IU/h) during 24 and 48 hours respectively. Residual stenotic lesions and occlusions were successfully treated with PTA alone in case 1 and with PTA in combination with a stent implantation in case 2. In accordance with Bean et al. (1985) and Goffette et al. (1989) we recommend local lysis in combination with PTA with or without additional stent implantation as an alternative treatment to surgery or systemic lysis for the treatment of Leriche's syndrome.

Adult↗