Search PubMed⌕ Search

Biomedical subjects

I Baumgartner

Publications and source records attributed to I Baumgartner.

At least 19 recordsLinked to original sources
PubMed2007

Influence of secondary infection on amputation in chronic critical limb ischemia.

OBJECTIVES: To evaluate the influence of secondary infection on major amputation in chronic critical leg ischemia (CLI). DESIGN: Prospective, controlled observational study. MATERIALS AND METHODS: Sixty-seven patients with CLI and ischemic lesions participated in the study. Presence of infection was defined by clinical, laboratory and radiological criteria. Patients were categorized as having no local infection, soft tissue infection or osteomyelitis treated without antibiotics, amoxicillin/clavulanacid for 1 month or ciprofloxacin and clindamycin for 3 months, respectively. Clinical outcome was assessed at 2, 6 and 12 months. Study endpoints were major amputation and mortality. Analyses were performed using the Kaplan-Meier method. RESULTS: Forty-seven of 67 patients had a local infection. Major amputation was lower in patients with successful revascularization as compared to patients unsuitable for or with failed (without) revascularization (0% vs 26%, p<0.01). In patients with successful revascularization the probability of complete healing was lower with secondary infection (23% vs 71%, p=0.03). In patients without revascularization complete healing was rare (<10%), but secondary infection did not influenced major amputation, mortality or serious adverse events. CONCLUSION: Secondary infection reduces the likelihood of successful healing following revascularisation of CLI.

Aged↗
PubMed2006

[Guidance of interventions in subintimal recanalization and fenestration of dissection membranes using a novel dual-lumen intravascular ultrasound catheter].

PURPOSE: To evaluate the feasibility and effectiveness of IVUS-guided puncture for gaining controlled target lumen reentry in subintimal recanalization of chronic iliac/femoral artery occlusions and in fenestration of aortic dissections. MATERIALS AND METHODS: Between 5/2004 and 12/2005 12 consecutive patients (7 male, 5 female; mean age 64.6 +/- 12.0 years) with chronic critical limb ischemia and ischemic complications of aortic dissection were treated using the Pioneer catheter. This 6.2-F dual-lumen catheter combines a 20-MHz IVUS transducer with a pre-shaped extendable, hollow 24-gauge nitinol needle. This coaxial needle allows real-time IVUS-guided puncture of the target lumen and after successful reentry a 0.014" guidewire may be advanced through the needle into the target lumen. 7 patients were treated for aortic dissection and 5 patients (with failed previous attempts at subintimal recanalization) for chronic arterial occlusion. Patients with aortic dissection (5 type A dissections, 2 type B dissections) had developed renal ischemia (n = 2), renal and mesenteric ischemia (n = 2), or low extremity ischemia (n = 3). Patients with chronic arterial occlusions (2 common iliac artery occlusions, 3 superficial femoral artery occlusions) experienced ischemic rest pain (n = 4), and a non-healing foot ulcer (n = 1). RESULTS: The technical success rate using the Pioneer catheter was 100%. The recanalization/fenestration time was 37 +/- 12 min. Procedure-related complications did not occur. In 10 cases a significant improvement of clinical symptoms was evident. One patient with aortic dissection and ischemic paraplegia required subsequent surgical intervention. One patient had persistent ischemic rest pain despite successful recanalization of a superficial femoral artery occlusion. CONCLUSION: The Pioneer catheter is a reliable device which may be helpful for achieving target lumen reentry in subintimal recanalization of chronic occlusions and in fenestration of aortic dissections.

Aged↗
PubMed2006

Endovascular stenting of a renal transplant vein.

We describe successful endovascular stenting of a high-grade stenosis of a renal transplant vein in a 53-year old patient. Kidney transplantation had been performed due to IgA nephropathy and the patient had become symptomatic two months after uneventful recovery from operation.

Angioplasty, Balloon↗
PubMed2005

Association of cardiovascular risk factors with pattern of lower limb atherosclerosis in 2659 patients undergoing angioplasty.

OBJECTIVES: Aim of this study is to correlate distribution pattern of lower limb atherosclerosis with cardiovascular risk factor profile of patients with peripheral arterial occlusive disease (PAD). PATIENTS AND METHODS: Analysis is based on a consecutive series of 2659 patients (1583 men, 1076 women, 70+/-11 years) with chronic PAD of atherosclerotic origin undergoing primary endovascular treatment of lower extremity arteries. Pattern of atherosclerosis was grouped into iliac (n=1166), femoropopliteal (n=2151) and infrageniculate (n=888) disease defined according to target lesions treated. A multivariable multinomial logistic regression analysis was performed to assess relation with age, gender and classical cardiovascular risk factors (diabetes mellitus, arterial hypertension, hypercholesterolemia, cigarette smoking) using femoropopliteal disease as reference. RESULTS: Iliac disease was associated with younger age (RRR 0.95 per year of age, 95%-CI 0.94-0.96, p<0.001), male gender (RRR 1.32, 95%-CI 1.09-1.59, p=0.004) and cigarette smoking (RRR 2.02, 95%-CI 1.68-2.42, p<0.001). Infrageniculate disease was associated with higher age (RRR 1.02, 95%-CI 1.01-1.02, p<0.001), male gender (RRR 1.23, 95%-CI 1.06-1.41, p=0.005) and diabetes mellitus (RRR 1.68, 95%-CI 1.47-1.92, p<0.001). Hypercholesterolemia was less prevalent in patients with lesions below the knee (RRR 0.82, 95%-CI 0.71-0.94, p=0.006), whereas no distinct pattern was apparent related to arterial hypertension. CONCLUSION: Clinical phenotype of peripheral atherosclerosis varies with prevalence of cardiovascular risk factors suggesting differences in mechanisms involved in iliac as compared with infrageniculate lesions. Identification of molecular mechanism might have influence on future therapeutic strategies in PAD patients.

Age Factors↗
PubMed2005

Current evidence and prospects for medical treatment of abdominal aortic aneurysms.

Abdominal aortic aneurysm (AAA) is a potentially fatal condition with risk of rupture increasing as maximum AAA diameter increases. It is agreed upon that open surgical or endovascular treatment is indicated if maximum AAA diameter exceeds 5 to 5.5 cm. Continuing aneurysmal degeneration of aortoiliac arteries accounts for significant morbidity, especially in patients undergoing endovascular AAA repair. Purpose of this review is to give an overview of the current evidence of medical treatment of AAA and describe prospects ofpotential pharmacological approaches towards prevention of aneurysmal degeneration of small AAAs and to highlight possible adjunctive medical treatment approaches after open surgical or endovascular AAA therapy.

Anti-Bacterial Agents↗
PubMed2005

Automated software supported versus manual aorto-iliac diameter measurements in CT angiography of patients with abdominal aortic aneurysms: assessment of inter- and intraobserver variation.

BACKGROUND: Open surgical or endovascular abdominal aortic aneurysm (AAA) relies on precise preprocedual imaging. Purpose of this study was to assess inter- and intraobserver variation of software-supported automated and manual multi row detector CT angiography (MDCTA) in aortoiliac diameter measurements before AAA repair. PATIENTS AND METHODS: Thirty original MDCTA data sets (4 x 2mm collimation) of patients scheduled for endovascular AAA repair were studied on a dedicated software capable of creating two-dimensional reformatted planes orthogonal to the aortoiliac center-line. Measurements were performed twice with afour-week interval between readings. Data were analysed by two blinded readers at random order Two different measurement methods were performed: reader-assisted freehand wall-to-wall measurement and semi-automatic measurement. RESULTS: Aortoiliac diameters were significantly underestimated by the semi-automatic method as compared to reader-assisted measurements (p < 0.0031). Intraobserver variability of AAA diameter calculation was not significant (p > 0. 15) for reader-assisted measurements except for the diameter of the left common iliac artery in reader 2 (p = 0.0045) and it was not significant (p > 0. 14) using the semi-automatic method. Interobserver variability was not significant for AAA diameter measurements using the reader-assisted method and for proximal neck analysis with the semiautomatic method (p > 0.27). Relevant interobserver variation was observed for semi-automatic measurement of maximum AAA (p = 0.0007) and iliac artery diameters (p = 0.024). CONCLUSIONS: Dedicated MDCTA software provides a useful tool to minimize aortoiliac diameter measurement variation and to improve imaging precision before AAA repair. For reliable AAA diameter analysis the reader-assisted freehand measurement method is recommended to be applied to a set of reformatted CT data as provided by the software used in this study.

Aged↗
PubMed2005

Management of peripheral vascular disease.

The management of patients with peripheral arterial occlusive disease (PAD) has to be planned in the context of natural history, epidemiology, and apparent risk factors that predict deterioration. The ankle-brachial index to date has proved to be the most effective, accurate, and practical method of PAD detection. Given that PAD is a powerful indicator of systemic atherosclerosis and (independent of symptoms) is associated with an increased risk of myocardial infarction and stroke, as well as a six times greater likelihood of death, the prevalence and demographic distribution of measurable PAD becomes particularly relevant. Reliable information on interventions to confer symptom relief is much weaker and reflects discrepancies between published reports from centers of excellence and the experience of patients routinely treated in communities around the world. The impact of newer treatment modalities, such as complex endovascular procedures and therapeutic angiogenesis, has been a subject of recent controversy.

Angioplasty, Balloon↗
PubMed2004

Bovine mesenteric vein graft (ProCol) in critical limb ischaemia with tissue loss and infection.

OBJECTIVES: Poor results have been reported following infrainguinal reconstructions using heterogenous grafts. The objective of this study was to assess the use of bovine mesenteric vein (ProCol) graft in patients with critical limb ischaemia (CLI), tissue loss/infection and no autologous vein available for reconstruction. METHODS: Prospective analysis of 32 patients with CLI and tissue loss/infection, in whom reconstruction with ProCol was undertaken between October 1999 and May 2002. RESULTS: The primary patency rate was 16% at 1 month. After thrombectomy, the secondary patency rate was 50% at 1 month and 26% at 14 months. No graft infections were seen. Aneurysmal dilatation of the graft occurred in 2 (6%). Limb salvage at 14 months was 47%. CONCLUSION: In patients with critical limb ischaemia, tissue loss/infection and no available vein, the ProCol graft may be an alternative. However, primary patency is a problem. In situations without tissue loss/infection, where the risk of graft infection is less, prosthetic material may be a better alternative.

Adult↗
PubMed2004

Delay of dialysis in end-stage renal failure: prospective study on percutaneous renal artery interventions.

BACKGROUND: Renal artery stenosis (RAS) is a cause of end-stage renal failure. We studied the effect of percutaneous renal artery intervention (PRI) in patients with advanced, progressive disease at risk for renal failure, hypothesizing a beneficial effect. METHODS: Thirty-nine primary and 14 secondary PRIs were performed on 28 patients with atherosclerotic RAS, serum creatinine >300 micromol/L, and progressive loss of renal function >/=1 year before PRI. Renal function and RA patency were prospectively followed for 12 months after primary and secondary PRI. The intervention's effect on the progressive loss of renal function was calculated by comparing reciprocal slopes of serum creatinine against time before and after PRI. RESULTS: Progression of renal failure slowed significantly following PRI. Mean (+/-SE) slopes of reciprocal serum creatinine values were: 6.69 +/- 0.97 L micromol(-1) day(-1) (x10(-6)) before and 6.76 +/- 3.03 L micromol(-1) day(-1) (x10(-6)) after PRI (P= 0.0007). Fifteen patients (53.5%) showed improvement or stabilization of progressive renal dysfunction. Out of 11 patients expected to become dialysis dependent within one year, 8 (72.7%) experienced an improvement in renal function sufficient to remain dialysis-free. Favorable outcome correlated with a lower creatinine level (P= 0.0137) and a more negative slope of progression (r= 0.49, P= 0.020) at entry. Mortality was 10.7%, and rate of local complications was 7.1%. Deterioration of renal function following PRI was suspected in 17.9% of patients. CONCLUSION: PRI may improve renal function and ultimately delay dialysis in patients with advanced renal failure. Possible advantages must be weighed against the risk of renal failure advancement and high procedure-related complication rate.

Aged↗
PubMed2003

Does infection affect amputation rate in chronic critical leg ischemia?

BACKGROUND: Aim was to analyze the association between local infection and amputation rate in patients with chronic critical limb ischemia (CLI) with or without successful revascularization. PATIENTS AND METHODS: We performed a retrospective analysis of 56 consecutive patients with 57 critically ischemic legs seen at the University Hospital Bern. Patients with CLI were selected if ischemic lesions and follow-up of more than 2 months were documented. Infection was suggested when 2 of the following criterion were present: temperature > 37 degrees C, C-reactive protein > 50 mg/L, leukocytes > 10 x 10(3)/microliter ("2 of 3" criterion), or a putrid secretion was documented ("secretion" criterion). RESULTS: In patients with successful revascularization (n = 39), there was a significant shift from 10.3% major to 33.3% minor amputations (Chi Square p value = 0.014) as compared to patients without or with failed revascularization (n = 18) with 44.4% and 11.1% (Chi Square p value = 0.008), respectively. An infection was suggested in 22 of 53 limbs (41.5%) according to the "2 of 3" criterion, and 30 of 57 limbs (52.6%) satisfying the "secretion" criterion. Both criteria, were significantly more common in patients undergoing amputation as compared to patients without amputation (p = 0.001). Multiple lesions were more common in patients with major amputations (p = 0.026). CONCLUSION: Successful revascularization effectively reduces major amputations and leads to healing of ischemic ulcers. Secondary foot infections are frequent. Infections are associated with a significantly higher rate of minor and major amputations, also in patients with successful revascularization, and should be treated adequately as well as in time with antibiotics.

Adult↗
PubMed2002

Effects of exercise training program on functional capacity and quality of life in patients with peripheral arterial occlusive disease. Evaluation of a pilot project.

BACKGROUND: In patients with peripheral arterial occlusive disease (PAOD) stage II, exercise training seems to be important to reduce symptoms and improve functional capacity. We evaluated the effects of an out-patient treatment program on walking distance (standardized treadmill testing), training exercise capacity, and disease specific quality of life (PAVK-86 questionnaire). METHODS AND RESULTS: Thirty-one patients aged 70 +/- 2 with intermittent claudicatio in stage IIa/IIb according to Fontaine (n = 18/13) underwent a supervised 12 week exercise training and education outpatient program. During course of intervention, patients demonstrated improvements in pain-free training walking distance (p < 0.001) and repetitions of tiptoe standing (p < 0.05). In standardized treadmill testing, pain-free walking distance was improved by 182% (129 +/- 19 m-->364 +/- 53 m; p < 0.001), and maximum walking distance by 76% (311 +/- 42 m-->546 +/- 63 m; p < 0.01). Before training, mean subscale scores of the PAVK-86 demonstrated distinct impairments concerning pain and functional status. After 12 weeks of intervention, with exception of the subscale complaints, all dimensions of quality of life assessed have improved significantly. The highest effect size was observed for the subscales pain, mood, and functional status. Improvement in the subscale anxiety and pain-free walking distance (treadmill test) correlated significantly (r = 0.46) as well as improvement in the subscale mood and maximum walking distance (r = 0.45). CONCLUSION: In patients with PAOD stage II considerable effects on functional capacity and important dimensions of quality of life can be achieved by a short exercise and education program.

Aged↗
PubMed2002

Evaluation of clinical tests to assess perfusion in chronic critical limb ischemia.

BACKGROUND: Evaluation of macro- and microcirculatory tests to confirm diagnosis, and recognize perfusion changes in chronic critical limb ischemia (CLI). PATIENTS AND METHODS: Forty-two consecutive patients with CLI examined at the University Hospital Bern, with 21 included in this prospective follow-up analysis. Patients underwent serial clinical examinations, and assessment of the macro- (ankle arterial pressure [AP], great toe pressure [TP], oscillography) and microcirculation (transcutaneous partial oxygen pressure [tcPO2] recumbent, sitting, O2-inhalation; capillary microscopy) at baseline, 6 weeks after revascularization (group 1; [n = 11]), or after 10 weeks in patients unsuitable for revascularization (group 2; [n = 10]). Clinical improvement was considered to indicate increased perfusion. RESULTS: Eleven patients with revascularization (11/11), and 2 without revascularization (2/10) showed clinical improvement. AP measurements were not reliable or feasible in 9 (43%), TP in 4 patients (19%), respectively. All measurable pressures were in accordance to clinical course. Oszillography gave a moderate perception of perfusion changes. Baseline tcPO2 levels were critical (< 30 mmHg) in all 21 patients, whereas follow-up gave poor correlation with the clinical course. Reliability to detect perfusion changes increased by adding provocation manoeuvers in patients with clinical improvement (39% [5/13] recumbent, 77% [10/13] sitting, 85% [11/13] O2-inhalation). Capillary microscopy revealed a relevant pathology at the forefoot level in all patients with feasible examinations (18/21), and significant improvements according to the clinical course in 92% of patients (12/13). CONCLUSIONS: TP measurements represented most reliable test to confirm diagnosis and disclose improved perfusion in CLI. TcPO2 measurements in recumbent position gave unreliable results, improved by provocation manoeuvers. Capillary microscopy was reliable, but time consuming and limited by anatomical restrictions.

Aged↗
PubMed2002

Treatment of renal artery fibromuscular dysplasia with balloon angioplasty: a prospective follow-up study.

OBJECTIVES: to assess restenosis rates and blood pressure response after percutaneous transluminal renal angioplasty (PTRA) in patients treated for fibromuscular dysplastic renal artery stenosis. METHODS: a prospective 12-month follow-up study of 27 patients with 31 treated renal artery stenosis. Follow-up assessment included colour-coded duplex sonography (CCD) of renal arteries, monitoring of blood pressure, antihypertensive medication, and creatinine measurements before discharge and at 3, 6, and 12 months. Primary end point was defined as a haemodynamically significant restenosis >60% assessed by CCD. RESULTS: there was a cumulative 23% restenosis rate at 12 months. Arterial hypertension was cured or improved in 93% of patients immediately after the intervention and remained cured/improved in 74% of patients at 12 months of follow-up. Renal failure present in five patients before PTRA stabilised or improved in all patients. CONCLUSION: although restenosis rate after PTRA in fibromuscular dysplasia is as high as in non-ostial atherosclerotic lesions, there remains a considerable higher therapeutic effect. Profound pressure response and recurrent arterial hypertension with restenosis support the high probability of a renovascular origin of arterial hypertension in this young and otherwise healthy population compared to patients with atherosclerotic renal artery lesions.

Adult↗
PubMed2002

[Low-osmolar gadodiamide as alternative contrast agent for diagnostic angiography and angiographic interventions in patients with renal insufficiency].

PURPOSE: To evaluate the benefit and feasibility of gadolinium contrast agents for intra-arterial use in diagnostic and therapeutic angiography in patients with renal insufficiency. METHODS: In 15 patients with planned peripheral or renal vascular interventions digital subtraction angiography with intra-arterial administration of gadolinium (gadodiamide n = 14, gadolinium-DTPA n = 1) was performed. Gadolinium was used selectively after peripheral catheter placement, mainly as an adjunct to CO2 (n = 12), to assess the distal run-off vessels or to characterize stenotic lesions. RESULTS: In 14 cases gadolinium yielded good or satisfactory results that were superior to those of CO2 angiography in the femoropopliteal region and calf, but also to the aorto-iliac vessels and the renal arteries. A small amount of iodinated contrast media was administered due to insufficient contrast of gadolinium in one patient. Mean serum creatinine level after angiography (295 +/- 167 micromol/l; range 125 - 764 micromol/l) was not significantly different (p >/= 0,37) from the initial level (279 +/- 149 micromol/l; range 143 - 728 micromol/l). CONCLUSION: Gadolinium is a viable alternative contrast agent for digital subtraction angiography and percutaneous transluminal angioplasty in patients with renal insufficiency. It enhances the diagnostic evaluation of stenosis and run-off vessels.

Adult↗
PubMed2001

Carotid dissection with and without ischemic events: local symptoms and cerebral artery findings.

OBJECTIVE: To study whether spontaneous dissections of the cervical internal carotid artery dissection (ICAD) with and without ischemia of the brain or retina differ in the prevalence of vascular risk factors, local neurologic signs and symptoms, and stenoses and occlusions of the cerebral arteries. METHODS: The authors prospectively studied 181 consecutive patients with 200 ICAD. Diagnosis was based on ultrasonography and MRI or catheter angiography. Vascular risk factors, presenting local (headache, neck pain, Horner syndrome, pulsatile tinnitus, cranial nerve palsy on the side of the ICAD) and ischemic signs and symptoms, and ultrasonographic findings in the carotid and basal cerebral arteries were evaluated. RESULTS: ICAD with ischemic events (n = 145) had a higher prevalence of hypercholesterolemia (p < 0.05), >80% stenoses and occlusions of the ICA (p < 0.0001), and intracranial obstructions (p < 0.001). ICAD without ischemic events (n = 55) had a higher prevalence of Horner syndrome (p < 0.001), cranial nerve palsy (p < 0.01), and normal ICA findings (p < 0.0001). CONCLUSIONS: These data suggest that ICAD causing high-grade stenosis and occlusion are more likely to lead to intracranial obstructions and cerebral or retinal ischemic events. Conversely, ICAD without luminal narrowing cause more local signs and symptoms.

Adolescent↗
PubMed2001

Quantitative (1)H magnetic resonance spectroscopy of myoglobin de- and reoxygenation in skeletal muscle: reproducibility and effects of location and disease.

1H-magnetic resonance spectroscopy ((1)H-MRS) of deoxymyoglobin (DMb) provides a means to noninvasively monitor the oxygenation state of human skeletal muscle in work and disease. As shown in this work, it also offers the opportunity to measure the absolute tissue content of DMb, the basic oxygen consumption of resting muscle, and the reperfusion characteristics after release of a pressure cuff. The methodology to determine these tissue properties simultaneously at two positions along the calf is presented. The obtained values are in agreement with invasive determinations. The reproducibility of the (1)H-MRS measurements is established for healthy controls and patients with peripheral arterial disease (PAD). A location dependence in axial direction, as well as differences between controls and patients are demonstrated for all parameters. The reoxygenation time in particular is expected to provide a means to quantitatively monitor therapies aimed at improving muscular perfusion in these patients.

Adult↗
PubMed2001

[Assessment of intraoperative duplex sonography during carotid endarterectomy].

INTRODUCTION: Carotid endarterectomy (CEA) for prevention of strokes mandates a high amount of experience and a meticulous surgical technique. Intraoperative morphologic as well as hemodynamic monitoring of the endarterectomized arteries is rarely performed. The purpose of this study was to determine the value of intraoperative colour-coded-duplex-sonography to recognize eventual intraoperative technical problems that might result in serious cerebral damage. METHODS: Prospective analysis of the medical data of all patients who underwent CEA for treatment of high-grade carotid stenosis between 1996 and 1999. Adequacy of the repair was assessed intraoperatively by duplexsonography. RESULTS: Of 142 consecutive patients with a median age of 68 (43-84) years, 104 (73 %) were men and 38 (27 %) were women. 9 patients (6 %) had bilateral CEAs. Intraoperative duplexsonography revealed abnormalities during 11 (7 %) of 151 CEAs. 4 (3 %) were considered major and underwent immediate revision. There was one (0.7 %) temporary neurologic deficit (hyperperfusion syndrome) and 2 (1.3 %) cases of fatal intracerebral hemorrhage. 6 (4 %) postoperative surgical complications occurred, i. e. 3 cases of major wound hematoma (with revision) and 3 cases of temporary cranial nerve palsy. Median length of follow-up was 11 (3-35) months. No late neurologic event occurred during follow-up. 5 (3 %) patients developed asymptomatic restenosis. DISCUSSION: Routine intraoperative duplexsonography is a valuable and reliable diagnostic tool to detect correctable technical problems during CEA that subsequently may lead to neurological deficits, fatal stroke or a high incidence of restenosis.

Adult↗