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Publications (5)32.37 Total impact

  • Article: Endovascular brachytherapy for prophylaxis of restenosis after femoropopliteal angioplasty: five-year follow-up--prospective randomized study.
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    ABSTRACT: To report the 5-year results from the prospective randomized Vienna-2 trial, which was designed to evaluate the safety and effectiveness of adjunctive endovascular brachytherapy (EBT) compared with no further treatment after successful revascularization in patients with long-segment femoropopliteal lesions. Each patient gave written informed consent to participate in the study, which was approved by the hospital's ethics committee. One hundred two patients (men, 53.9%; mean age, 72.1 years +/- 8.7 [standard deviation]; lesion length, 8.1 cm +/- 4.9) underwent percutaneous transluminal angioplasty (PTA) without further stent implantation. Patients were then assigned to either receive EBT (n = 51) by using an iridium 192 source, with a prescribed dose of 12 Gy at 3 mm from the source axis, or no further treatment (n = 51). Radiation was delivered without a centering catheter. Data were analyzed by using a Student t test for continuous values and a chi(2) test to compare categorical values. A Cox proportional hazards regression analysis was performed to evaluate predictors of recurrence at follow-up. After 6 months, the restenosis rate for the 102 patients with completed 5-year follow-up was significantly reduced for the PTA plus EBT group versus the PTA alone group (29.4% vs 56.9%, P < .05). During follow-up we observed a late catch-up phenomenon, and after 5 years the recurrence rate was comparable in both groups (72.5% vs 72.5%, P > .99). Time to recurrence, however, was significantly delayed in the PTA plus EBT group (17.5 months +/- 14.7 vs 7.4 months +/- 6.8 for the PTA alone group, P < .05). At 5-year follow-up, PTA followed by gamma radiation EBT with a dose of 12 Gy resulted in a delay but not an inhibition of restenosis when compared with that of PTA alone.
    Radiology 09/2006; 240(3):878-84. · 5.73 Impact Factor
  • Article: Endovascular brachytherapy: restenosis in de novo versus recurrent lesions of femoropopliteal artery--the Vienna experience.
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    ABSTRACT: To determine the effectiveness of endovascular brachytherapy in the prevention of restenosis in recurrent versus de novo femoropopliteal lesions. Ethics committee approval and patient informed consent were obtained. After they had undergone femoropopliteal angioplasty, 199 patients (mean age, 71.9 years +/- 9.6; 115 men, 84 women) were treated with either percutaneous transluminal angioplasty (PTA) and brachytherapy (n = 100) or PTA alone (n = 99). The patients were part of prospective randomized trials, the Vienna 2 and 3 trials, and were evaluated according to the stratification criterion of de novo or recurrent disease. Sixty-six of 134 patients with a de novo lesion and 34 of 65 patients with a recurrent lesion were randomly assigned to the PTA and brachytherapy arm; the remaining patients were treated with PTA alone. Outcomes were compared between the groups. The Student t test or one-way analysis of variance was used to compare continuous variables, and the chi2 test or Fisher exact test was used to assess dichotomous variables. Kaplan-Meier curves were calculated, and the log-rank test was performed to determine freedom from recurrence at 12 months in both groups. A multivariate Cox proportional hazard regression analysis was performed to evaluate the multivariate predictors of recurrence at 12-month follow-up. For patients with de novo lesions, the frequency of recurrence at 12 months was not significantly different between those who underwent brachytherapy and PTA and those who underwent PTA alone (24 [36%] of 66 patients vs 30 [44%] of 68 patients, P = .32). For patients with recurrent lesions, however, the 12-month recurrence rate was significantly lower in those who received brachytherapy than in those who did not (nine [26%] of 34 patients vs 22 [71%] of 31 patients, P = .004). Endovascular brachytherapy with gamma radiation significantly reduces the restenosis rate after femoropopliteal angioplasty of recurrent but not de novo lesions.
    Radiology 08/2005; 236(1):338-42. · 5.73 Impact Factor
  • Article: The med AUSTRON/OGRO patterns of care study on radiotherapy indications in Austria.
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    ABSTRACT: In Austria a national survey was conducted by Med AUSTRON/Osterreichische Gesellschaft for Radio--Onkologie, Radiobiologie und Medizinische Radiophysik (OGRO) in order to estimate the indications, patient numbers and radiotherapy treatment planning procedures and performances at all Austrian radiotherapy institutes. Results were correlated with incidence rates (Austrian cancer registry) to determine patterns of radiotherapy practice in Austria. At 12 radiotherapy departments of Austria data of all patients receiving irradiation within a 3 months (2002/2003) period were assessed. On the basis of a questionnaire number of treated patients, indications, and parameters of disease (stage, histology) and treatment modalities were evaluated. Results were analysed with regard to different tumour groups, according to academic and non academic hospitals, and correlated with epidemiological data on cancer incidence. In total, 3783 patients were registered within this period. According to the different tumour entities percentages of patients receiving radiotherapy within initial treatment varied from 3% to 90 % (e.g. brain tumours: 77%, breast cancer: 90%, prostate cancer: 35%). The most frequent indications to radiotherapy per radiotherapy department were breast cancer (range 22%-35%; mean 26%), urological tumours (range 6%-27%; mean 12%) and bone metastases (mean 10%, range 3%-17%). In Austria breast cancer, urological tumours and bone metastases are representing the most common indications to radiotherapy. Among the different departments variations in indications to radiotherapy were observed. Our study is the first evaluation of radiotherapeutic management in Austria.
    Radiotherapy and Oncology 01/2005; 73 Suppl 2:S29-34. · 5.58 Impact Factor
  • Article: Increased dosage during intracoronary irradiation due to overlapped source stepping shows no long-term adverse changes in vessel morphology.
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    ABSTRACT: The purpose of this analysis was to evaluate if overdosage during intracoronary irradiation due to overlapped source stepping may result in long-term morphologic changes in vessel anatomy. Baseline angiograms of patients with in-stent restenosis undergoing coronary reintervention followed by intracoronary irradiation with source stepping were analyzed. Overlapping was considered present for the segment with overlapped reference isodose length (RIL) (RIL = segment with > or = 90% of reference dose at 1 mm vessel wall depth). Baseline and 6-months follow-up volumetric intravascular ultrasound (IVUS) analysis were performed for the overlapped segment and for proximal and distal segments of equal length. Overlapping was found in six patients (three patients: (32)P treatment; three patients: (90)Sr/Y treatment); final analysis was performed in four patients. Comparison of the baseline and follow-up IVUS volumetric parameters revealed no significant change in lumen or vessel volumes at segments of overlaps in comparison to proximal and distal reference segments. Increased dosage due to overlapping during source stepping is not associated with morphologic changes in vessel anatomy at follow-up.
    Journal of Interventional Cardiology 06/2004; 17(3):143-9. · 1.18 Impact Factor
  • Article: Geographical miss during intracoronary irradiation: impact on restenosis and determination of required safety margin length.
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    ABSTRACT: The goal of this study was to evaluate the incidence and effects of underdosage of injured segments during intracoronary irradiation and to define the minimal length of safety margin required to avoid mismatched source placement. Underdosage of injured segments due to misplacement of active source has been suggested as the underlying mechanism for the occurrence of edge restenosis. Baseline angiograms of 112 vessels in 109 patients with in-stent restenosis undergoing coronary reintervention followed by intracoronary irradiation ((192)Ir: Checkmate, Cordis, Miami, Florida; (32)P: Gallileo, Guidant, Houston, Texas; (90)Sr/Y: Beta-Cath, Novoste, Norcross, Georgia) were analyzed. The distances between the outermost injury and outermost end of "reference isodose length" (RIL), defined as a segment with >/=90% of reference dose at 1 mm vessel wall depth, were measured. "Safety margin" was defined as the distance between the outermost injury and outermost end of the RIL, "geographical miss" (GM) as a complete injured segment not being covered by the RIL, and "restenosis" as the percent diameter stenosis >50%. Baseline angiographic analysis was performed for 224 edges in 112 vessels. Geographical miss was found in 46 (20.6%) edges. The incidence of target lesion restenosis within the 78 vessels with available follow-up was 43.3% for patients with GM versus 14.9% for patients with no GM (p = 0.005). Analysis of various injured segments exposed highest restenosis rates in injured segments with negligible irradiation (27.8%) in comparison with injured segments with dose fall-off (16.7%) or injured segments with full-dose irradiation (7.7%) (p = 0.006). Receiver operating curve analysis revealed a safety margin of 10 mm required per vessel (i.e., 5-mm safety margin/edge) to achieve 95% specificity of GM. Geographical miss is associated with a higher incidence of restenosis at the corresponding edges. Restenosis was more pronounced in injured segments with negligible irradiation than in injured segments at the dose fall-off zones. We recommend a safety margin of 10 mm per vessel to minimize GM.
    Journal of the American College of Cardiology 10/2002; 40(7):1225-31. · 14.16 Impact Factor