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Iris Baumgartner

Publications and source records attributed to Iris Baumgartner.

At least 19 recordsLinked to original sources
PubMed2006

Activated coagulation during open and endovascular abdominal aortic aneurysm repair.

OBJECTIVE: The study was conducted to determine activation of coagulation in patients undergoing open and endovascular infrarenal abdominal aortic aneurysm repair (EVAR). METHODS: In a prospective, comparative study, 30 consecutive patients undergoing open repair (n = 15) or EVAR (n = 15) were investigated. Blood samples to determine fibrinopeptide A, fibrin monomer, thrombin-antithrombin complex, and D-dimer were taken up to 5 days postoperatively. Routine hematologic and hematochemical parameters as well as clinical data were collected. RESULTS: Both groups showed comparable demographic variables. Operating time was longer in open repair (249 +/- 77 minutes vs 186 +/- 69 minutes, P < .05). Perioperatively elevated markers of coagulation were measured in both groups. Fibrinopeptide A levels did not differ significantly between the groups (P = .55). The levels of fibrin monomer and thrombin-antithrombin complex were significantly higher in patients undergoing EVAR (P < .0001), reflecting increased thrombin activity and thrombin formation compared with open surgery. The D-dimer level did not differ significantly between the groups. These results were also valid after correction for hemodilution. CONCLUSION: These data suggest increased procoagulant activity in EVAR compared with open surgery. A procoagulant state may favor possible morbidity derived from micro- and macrovascular thrombosis, such as in myocardial infarction, multiple organ dysfunction, venous thrombosis and thromboembolism, or disseminated intravascular coagulation.

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PubMed2006

Falsely high ankle-brachial index predicts major amputation in critical limb ischemia.

Falsely high ankle-brachial index (ABI) values are associated with an adverse clinical outcome in diabetes mellitus. The aim of the present study was to verify whether such an association also exists in patients with chronic critical limb ischemia (CLI) with and without diabetes. A total of 229 patients (74 +/- 11 years, 136 males, 244 limbs with CLI) were followed for 262 +/- 136 days. Incompressibility of lower limb arteries (ABI > 1.3) was found in 45 patients, and was associated with diabetes mellitus (p = 0.01) and renal insufficiency (p = 0.035). Limbs with incompressible ankle arteries had a higher rate of major amputation (p = 0.002 by log-rank). This association was confirmed by multivariate Cox regression analysis (relative risk [RR] 2.67; 95% CI 1.27-5.64, p = 0.01). The relationship between ABI > 1.3 and amputation rate persisted after subjects with diabetes and renal insufficiency had been removed from the analysis (RR 3.85; 95% CI 1.25-11.79, p = 0.018). Dividing limbs with measurable ankle pressure according to tertiles of ABI, the group in the second tertile (0.323 < or = ABI < or = 0.469) had the lowest amputation rate (4/64, 6.2%), and a U-shaped association between the occurrence of major amputation and ABI was evident. No association was found between ABI and mortality. In conclusion, this study demonstrates that falsely high ABI is an independent predictor of major amputation in patients with CLI.

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PubMed2006

Intravascular ultrasound-guided creation of re-entry sites to improve intermittent claudication in patients with aortic dissection.

PURPOSE: To report percutaneous fenestration of aortic dissection flaps to relieve distal ischemia using a novel intravascular ultrasound (IVUS)-guided fenestration device. CASE REPORTS: Two men (47 and 62 years of age) with aortic dissection and intermittent claudication had percutaneous ultrasound-guided fenestration performed under local anesthesia. Using an ipsilateral transfemoral approach, the intimal flap was punctured under real-time IVUS guidance using a needle-catheter combination through which a guidewire was placed across the dissection flap into the false lumen. The fenestration was achieved using balloon catheters of increasing diameter introduced over the guidewire. Stenting of the re-entry was performed in 1 patient to equalize pressure across the dissection membrane in both lumens. The procedures were performed successfully and without complications. In both patients, ankle-brachial indexes improved from 0.76 to 1.07 and from 0.8 to 1.1, respectively. Both patients were without claudication at the 3- and 6-month follow-up examination. CONCLUSION: Percutaneous intravascular ultrasound-guided fenestration and stenting at the level of the iliac artery in aortic dissection patients with claudication is a technically feasible and safe procedure and relieves symptoms.

Aortic Dissection↗
PubMed2005

Leg ischemia: assessment with MR angiography and spectroscopy.

PURPOSE: To prospectively determine reproducibility of magnetic resonance (MR) angiography and MR spectroscopy of deoxymyoglobin in assessment of collateral vessels and tissue perfusion in patients with critical limb ischemia (CLI) and to follow changes in patients undergoing intramuscular vascular endothelial growth factor (pVEGF)-C gene therapy, percutaneous transluminal angioplasty, supervised exercise training, or no therapy. MATERIALS AND METHODS: Study and gene therapy protocols were approved, and all patients gave written informed consent. To determine repeatability and reproducibility, seven patients underwent MR angiography and five underwent MR spectroscopy. The techniques were used to judge disease progress in 12 other patients with or without therapy: MR angiography to help determine change in visualization of collateral vessels and MR spectroscopy to help assess change in perfusion at proximal and distal calf levels. MR angiographic results were subjectively analyzed by three blinded readers. Intraobserver variability was expressed as 95% confidence interval (CI) (n=7); interobserver variability, as kappa statistic (n=15). Reexamination variability of MR spectroscopy was given as 95% CI for subsequent recovery times, and correlation with disease extent was calculated with Kendall taub rank correlation. Fisher-Yates test was used to correlate changes with pressure measurements and clinical course. RESULTS: Intraobserver and interobserver concordance was sensitive for detection of collateral vessels. Intraobserver agreement was 85.7% (95% CI: 42.1%, 99.6%). Interobserver agreement was high for small collateral vessels (kappa=0.74, P <.001) and fair for large collateral vessels (kappa=0.36, P=.002). MR spectroscopy was reproducible (95% CI: +/-26 seconds for proximal, +/-21 seconds for distal) and showed a correlation with disease extent (proximal calf, taub=0.84, P <.001; distal calf, taub=0.68, P=.04). Small collateral vessels increased over time (P=.04) but did not correlate with pressure measurements and clinical course. Recovery time correlated with clinical course (proximal calf, P=.03; distal calf, P=.005). CONCLUSION: MR angiography and MR spectroscopy of deoxymyoglobin can help document changes in visualization of collateral vessels and tissue perfusion in patients with CLI.

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PubMed2005

Arteriolization of capillaries and FGF-2 upregulation in skeletal muscles of patients with chronic peripheral arterial disease.

OBJECTIVE: Microvascular changes in ischemic skeletal muscle are described derived from patients with long-lasting peripheral arterial disease (PAD). METHODS: Skeletal muscles from the lower limb of 17 patients (obtained after amputation) with chronic PAD and 4 asymptomatic controls (obtained from biopsies after bypass surgery) were evaluated by electron microscopy and immunohistochemistry. RESULTS: The capillaries in skeletal muscles of PAD patients were surrounded by a more than 1 microm-thick coat, which was positively stained for basement membrane pericapillary coat collagen type IV. Thickness of the coat correlated with presence of PAD (p < .0001), and less strongly with diabetes mellitus (p = .023) and age of patients (p = .019). The majority of the capillaries in skeletal muscles of PAD patients (71.1 +/- 15.3%) were covered with cells positive for smooth muscle cell actin (sma) as compared to samples from asymptomatic controls (22.8% +/- 9.6%; p < .0001) suggesting advanced arteriolization. Semiquantitative analysis revealed that patients with PAD demonstrate a higher expression of FGF-2 in capillary endothelial cells (67.8 +/- 17.5%) as compared to controls (10.2 +/- 8.4%; p < .0001), whereas VEGF immunoreactivity was only occasionally present in extravascular cells. CONCLUSION: Thickened collagen type IV-positive basement membranes in combination with a significant increase in sma-coverage indicate arteriolization of capillaries characteristic for chronic PAD, what may be related to high FGF-2 expression in capillary endothelial cells.

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PubMed2005

Adjunctive abciximab improves patency and functional outcome in endovascular treatment of femoropopliteal occlusions: initial experience.

PURPOSE: To prospectively evaluate the safety and effectiveness of adjunctive administration of abciximab observed within 30 days and at 6 months after randomization in patients undergoing endovascular revascularization of long-segment femoropopliteal occlusions. MATERIALS AND METHODS: The study was approved by the local ethical committee, and patients gave written informed consent. In a prospective, double-blind, placebo-controlled design, patients undergoing percutaneous treatment for long-segment (>5 cm) femoropopliteal occlusions were randomly assigned to receive abciximab or a placebo; all patients also received standard-dose heparin. Effectiveness and safety analyses were based on an intention-to-treat approach. Patency was calculated according to life-table analysis, and P values were derived from the log-rank statistic. The P values for dichotomous safety end points were calculated with the Fisher exact test. Odds ratios were calculated for subgroup analyses. Logistic regression modeling was used for analysis of the safety bleeding data. RESULTS: A total of 98 patients (103 limbs) were included: 47 patients received abciximab and 51 received a placebo. Patency with abciximab versus placebo was 95.7% versus 80.4% (relative risk, 0.21; 95% confidence interval: 0.05, 0.96; P = .02) at 30 days and was 61.7% versus 41.2% (relative risk, 0.57; 95% confidence interval: 0.32, 1.01; P = .03), coupled with a better clinical outcome according to the Rutherford score, at the end of follow-up (P = .03). Risk of major bleeding was not significantly increased, while access-site bleeding was significantly higher among patients receiving abciximab (odds ratio, 2.9; 95% confidence interval: 1.04, 8.2; P = .04). CONCLUSION: The data show that adjunctive administration of abciximab has a favorable effect on patency and clinical outcome in patients undergoing complex femoropopliteal catheter interventions not hampered by serious bleeding. Treatment effect of abciximab observed at 30 days was maintained at 6-month follow-up.

Abciximab↗
PubMed2005

Systemic antiatherosclerotic treatment for the peripheral arterial occlusive disease patient.

Symptomatic and asymptomatic peripheral arterial occlusive disease (PAD) is indicative of widespread atherosclerosis. The major threat is from cardiovascular ischaemic events; thus, an important therapeutic goal is to modify atherosclerotic risk factors. Data from several large drug trials indicate that patients with PAD may gain as much, if not more, benefit from aggressive secondary prevention than those with other manifestations of atherothrombosis. In fact, the level of care for patients with PAD is lower as compared with those with ischaemic heart disease, although PAD is defined to be a coronary artery risk equivalent. This paper reviews observational data and generalisation from trials in patients with other manifestations of cardiovascular disease that support the importance of treating key risk factors such as smoking, diabetes, hypertension and hyperlipidaemia in PAD patients.

Antihypertensive Agents↗
PubMed2005

Endovascular treatment of an internal iliac artery aneurysm using a nitinol vascular occlusion plug.

PURPOSE: To report endovascular occlusion of an internal iliac artery (IIA) aneurysm with an Amplatz nitinol vascular occlusion plug. CASE REPORT: A 71-year-old asymptomatic man who had previously undergone open aortic aneurysm repair presented for annual follow-up. A bifurcated Dacron graft had been inserted 12 years ago from the infrarenal aorta to the left common femoral artery and the right common iliac artery. The left common iliac artery was ligated proximally, and the left external iliac artery (EIA) provided retrograde flow into the IIA. Magnetic resonance imaging (MRI) revealed a 7.4-cm aneurysm of the left IIA. After transfemoral calibrated catheter angiography was performed, the proximal EIA was occluded with an Amplatz nitinol vascular occlusion plug. In addition, microcoils were placed distal to the vascular plug to achieve complete thrombosis of the vessel. One day after treatment, the patient was discharged free of symptoms after MRI had shown complete obliteration of the IIA aneurysm. At 6 months, the patient was free from symptoms, and angiography confirmed exclusion of the IIA aneurysm. CONCLUSIONS: This case illustrates the technical feasibility and successful short-term follow-up of a novel embolization approach to IIA aneurysms in patients with an aortofemoral graft.

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PubMed2005

Endovascular brachytherapy after femoropopliteal balloon angioplasty fails to show robust clinical benefit over time.

PURPOSE: To determine if the short-term efficacy of adjunctive endovascular brachytherapy (EVBT) is maintained over time in patients undergoing balloon angioplasty (BA) of femoropopliteal atherosclerotic lesions. METHODS: To evaluate the long-term clinical and angiographic outcome of EVBT, 147 consecutive patients (82 men; mean age 70.8+/-8.5 years) with 147 treated limbs were randomized to BA with (n=72, 49%) or without (n=75, 51%) adjunctive EVBT (12 or 14-Gy from an (192)Ir source, no centering, a 5-mm reference depth). Sixty-eight (46%) limbs were treated for de novo and 79 (54%) for recurrent femoropopliteal lesions. Clinical follow-up at 1, 3, 6, and 12 months and annually thereafter included evaluation of symptoms, ankle-brachial index (ABI), and intra-arterial angiography for new/worsening symptoms or at follow-up between 2 and 5 years. Sustained clinical success was defined as improvement in ABI >or=0.1 and/or of symptoms without repeated target lesion revascularization. Angiographic restenosis was defined as >or=50% diameter reduction. Subgroup analysis was performed for de novo versus recurrent lesions. RESULTS: Mean clinical follow-up was 32.3+/-21.5 months. Angiographic follow-up was available in 83 (56%) patients (41 BA and 42 BA+EVBT) at a mean 31.8+/-20.7 months. Cumulative sustained clinical success rates at 1, 2, and 3 years, respectively, were 84.3%, 82.1%, and 76.4% after BA versus 82.4%, 69.8%, and 67.5% after BA+EVBT (p=0.26 by log-rank). Although the proportion of patients undergoing follow-up angiography was moderate, the freedom from angiographic restenosis at 1, 2, and 3 years was 70.7%, 63.1%, and 47.1% after BA versus 82.7%, 64.3%, and 64.3% after BA+EVBT (p=0.16 by log-rank). No differences were found between BA and BA+EVBT outcomes in patients with de novo versus recurrent femoropopliteal lesions. CONCLUSION: The seemingly beneficial short-term effects of BA+EVBT are not sustained in the longer term, with no robust clinical improvement after angioplasty of atherosclerotic de novo or recurrent femoropopliteal lesions at up to 5 years.

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PubMed2005

Below-the-knee angioplasty in patients with end-stage renal disease.

PURPOSE: To determine clinical efficacy of below-the-knee (BTK) angioplasty in patients with end-stage renal disease (ESRD). METHODS: Interrogation of a prospectively maintained database containing 2,659 patients treated at a tertiary referral hospital between February 1995 and June 2004 identified 29 ESRD patients (21 men; median age 69 years, IQR 10.12) who had 73 infrapopliteal atherosclerotic lesions treated in 38 ischemic limbs. The indication for treatment was intermittent claudication in 13 (34%) and critical limb ischemia in 25 (66%) limbs. BTK angioplasty was attempted either alone (n=18) or combined with an endovascular inflow procedure (n=20). Primary clinical success was defined as hemodynamic improvement (ABI increase >or=0.1) and/or symptomatic improvement (at least one clinical category). Cumulative rates were calculated according to the Kaplan-Meier estimate. RESULTS: Primary technical success reached 97%, whereas hemodynamic improvement was obtained in only 50% (19/38) of the limbs treated. The pedal arteries were severely diseased in all, and complete occlusion of the pedal arch was found in 58% (18/31) of limbs on completion angiography. Median follow-up was 5.9 months (IQR 11.5). Primary clinical success was 17%, 11%, 11%, and 11% in patients with BTK angioplasty alone and 53%, 45%, 45%, and 45% in patients with inflow procedures after 3, 6, 9, and 12 months, respectively (p=0.017). Limb salvage was 73% at 12 months. Subgroup analyses showed significantly better clinical results in men (p=0.003) and in patients on hemodialysis compared to peritoneal dialysis (p=0.037). CONCLUSIONS: Clinical efficacy of BTK angioplasty is limited in patients with ESRD because of the severely diseased pedal arteries. Further studies are warranted to define subgroups of patients likely to experience a more favorable outcome.

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PubMed2004

Combined surgical and endovascular approach to treat a complex aortic coarctation without extracorporeal circulation.

Various therapeutic approaches have been proposed to treat complex coarctation of the aorta (eg, recoarctation, which requires repetitive interventions, or coarctation with a hypoplastic aortic arch). Resection followed by end-to-end anastomosis or by graft interposition is technically demanding and exposes the patient to considerable perioperative risks. Cardiopulmonary bypass and deep hypothermic circulatory arrest may be necessary to control the distal aortic arch. The role of stent technology in treating this type of lesion has not yet been defined. We present a 21-year-old woman with a recurrent coarctation of the aorta associated with a hypoplastic aortic arch and a pseudoaneurysm of the proximal descending aorta. She had undergone 4 previous interventions. Treatment consisted of a combined surgical and endovascular approach without cardiopulmonary bypass and included extraanatomic aortic bypass, partial debranching of the supraaortic vessels, and stent-graft insertion to exclude the aneurysm.

Adult↗
PubMed2004

Does deep femoral artery revascularization as an isolated procedure play a role in chronic critical limb ischemia?

PURPOSE: To prospectively evaluate the midterm outcome after balloon angioplasty or surgical profundaplasty of the deep femoral artery (DFA) as an isolated procedure in chronic critical limb ischemia (CLI). METHODS: Between 1995 and 2001, 21 limbs in 20 patients (mean age 77+/-8 years) were treated by revascularization of the deep femoral artery (DFA) as an isolated procedure for limb salvage. All patients had long-segment femoropopliteal occlusions unsuitable for revascularization and critical obstruction of the DFA. Clinical outcome was assessed at 1, 3, 6, and 12 months. Clinical treatment efficacy was defined as resolved CLI in surviving patients without major amputation after isolated DFA revascularization. Repeat target limb revascularization, major amputation, and death were solitary study endpoints; survival analyses were performed using the Kaplan-Meyer method. RESULTS: Angioplasty with or without stenting was performed in 14 (67%) limbs and surgical profundaplasty in 7 (33%) limbs, with a technical success rate of 100%. Clinical treatment efficacy was 25% at 12 months; the cumulative rates of repeat target limb revascularization, major amputation, and death were 49%, 36%, and 55%, respectively. Major amputation and persistent CLI dominated in patients with stage IV disease (89%), whereas rest pain resolved in the majority of patients with stage III disease (67%; p<0.05). CONCLUSIONS: Isolated DFA revascularization seems insufficient to support wound healing in CLI, but might be a treatment option in CLI patients with rest pain.

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PubMed2004

Effects of probucol versus aspirin and versus brachytherapy on restenosis after femoropopliteal angioplasty: the PAB randomized multicenter trial.

PURPOSE: To evaluate the effect of probucol and/or of endovascular brachytherapy (EVBT) on restenosis after percutaneous transluminal angioplasty (PTA) of femoropopliteal arteries. METHODS: A total of 335 patients (206 men; mean age 72+/-9 years) with intermittent claudication were randomized according to a 2x2 factorial design to 1 of the 4 groups: probucol, placebo, EVBT, and EVBT+probucol. Probucol (1 g/d) or placebo were given in double-blinded fashion 1 month before and for 6 months after PTA. Gamma irradiation (192Iridium, 14 Gy, 5-mm reference depth) was randomly applied in an unblinded manner from a noncentered endoluminal catheter. All patients received aspirin (100 mg/d). Primary endpoint was restenosis (>50% diameter reduction) detected by duplex ultrasound 6 months after PTA. Secondary endpoints included clinical and hemodynamic assessment. RESULTS: Restenosis in patients undergoing EVBT was 17% (23/133) versus 35% (50/142) in patients without EVBT (p<0.001); in patients treated with probucol versus placebo, the rates were 23% (31/135) and 30% (43/140, p<0.001). Three quarters (77%, 102/133) of patients were free of claudication after EVBT therapy versus 61% (87/142) without EVBT (p<0.05). Need for target vessel revascularization was 6% (8/133) with EVBT versus 14% (20/142) without EVBT (p<0.01). Late thrombotic occlusions occurred in 4% (6/133), exclusively in patients treated with EVBT after stent implantation. CONCLUSIONS: Endovascular brachytherapy significantly reduces restenosis, improves symptoms, and reduces reinterventions after PTA of femoropopliteal arteries. Probucol reduces restenosis but has no additive effect when combined with brachytherapy.

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