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(Circulation. 2000;102:2694.)
© 2000 American Heart Association, Inc.
Clinical Investigation and Reports |
Endovascular Brachytherapy for Prophylaxis of Restenosis After Femoropopliteal Angioplasty
Results of a Prospective Randomized Study
From the Department of Angiology (E.M., T.M., R.A., R.W.), the Department of Radiotherapy and Radiobiology (B.P., C.F., W.S., R.P.), and the Department of Medical Computer Sciences (M.M.), University of Vienna, General Hospital Vienna, Vienna, Austria.
Correspondence to Prof Erich Minar, Department of Angiology, University of Vienna, General Hospital Vienna, A-1097 Vienna, Austria. E-mail erich.minar{at}akh-wien.ac.at
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Abstract |
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Background—Inasmuch as endovascular brachytherapy (BT) has gained recent interest because of its inhibitory effect on mechanisms leading to restenosis after percutaneous transluminal angioplasty (PTA), we performed this randomized study to determine its efficacy for prophylaxis of restenosis after femoropopliteal PTA.
Methods and Results—One
hundred thirteen patients (63 men, 50 women; mean age 71 years) with de
novo or recurrent femoropopliteal lesions were included in this
randomized trial comparing the restenosis rate after PTA plus BT (57
patients, PTA+BT group) versus PTA (56 patients, PTA group) without
stent implantation. The mean treated length was 16.7 cm (PTA+BT group)
versus 14.8 cm (PTA group). In patients randomized to PTA plus BT, a
dose of 12 Gy was applied by an 192Ir source
3 mm from the source axis. Follow-up examinations included measurement
of the ankle-brachial index, color-flow duplex sonography, and
angiography. The primary end point of the study was patency after 6
months. The overall recurrence rate after 6 months was 15 (28.3%) of
53 in the PTA+BT group versus 29 (53.7%) of 54 in the PTA group
(
2 test, P<0.05). The
cumulative patency rates at 12 months of follow-up were 63.6% in the
PTA+BT group and 35.3% in the PTA group (log-rank test,
P<0.005).
Conclusions—This is the first randomized study to demonstrate the efficacy of endovascular BT for prophylaxis of restenosis after femoropopliteal PTA. The value of this approach should now be improved by modification of the BT procedure and by combination with stent implantation.
Key Words: peripheral vascular disease • angioplasty • restenosis • radioisotopes
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Introduction |
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TopAbstractIntroductionMethodsResultsDiscussionReferences |
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Restenosis still remains a major limitation of the clinical usefulness of percutaneous transluminal angioplasty (PTA), and poor long-term results, especially after treatment of longer lesions in the femoropopliteal region, have been reported.1 2 Numerous pharmacological and mechanical adjuncts have been tried without success.
The potential role of radiation in the prevention of restenosis after angioplasty has generated much recent interest. Ionizing radiation inhibits cellular proliferation and has been used extensively in the treatment of neoplastic and nonneoplastic diseases. The rationale in experimental studies to apply irradiation to prevent restenosis is that the latter is mediated at least in part by an uncontrolled proliferation of smooth muscle cells.3 Endovascular brachytherapy (BT) has shown strong potential in controlling this pathological proliferation process in animal models of restenosis.4 Findings of recent clinical studies suggest a substantial reduction in the restenosis rate with intraluminal irradiation of coronary5 and peripheral6 arteries in conjunction with angioplasty and stent implantation. In a recent pilot study,7 we demonstrated promising results concerning the possibility of reduction of restenosis by means of endovascular BT after long-segment femoropopliteal PTA without stent implantation. Therefore, we performed the present randomized study to determine the efficacy of endovascular BT for prophylaxis of restenosis after femoropopliteal PTA.
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Methods |
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TopAbstractIntroductionMethodsResultsDiscussionReferences |
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Patients
Each patient gave his or her written informed consent to participate in the study, which was approved by the hospital’s ethics committee.
Between November 1, 1996, and August 31, 1998, a total of 214 consecutive patients who were treated in our center with PTA for femoropopliteal lesions were screened for entry into the present study. To be eligible, the patients had to fulfill the following criteria: (1) minimum age of 40 years, (2) history of claudication (according to Rutherford stage 2 or 3)8 for >3 months or critical limb ischemia with pain at rest with or without tissue damage, (3) de novo lesion in the femoropopliteal region with a minimal lesion length of 5 cm or a recurrent lesion (after former PTA) of any length, (4) technical success of the angioplasty procedure that required angiographic patency with residual stenosis of <30% diameter reduction, and (5) no further stent implantation. According to these criteria, 117 patients were included in the present study.
After successful PTA, the patients were randomly allocated
to further BT or no further treatment. The patients were assigned to
either group by adaptive
randomization9 by
using the following stratification criteria: (1) de novo lesion (
5
cm) versus recurrent lesion (any length), (2) stenosis versus
occlusion, and (3) clinical stage (claudication versus critical limb
ischemia). Four of the 117 randomized patients were excluded from
further follow-up (1 patient refused the BT procedure after
randomization, and 3 patients, 2 in the PTA+BT group and 1 in the PTA
group, had early recurrence within 24 hours). The baseline
characteristics of the remaining 113 study patients (mean age 71 [43
to 89] years) with presenting symptoms, associated diseases and risk
factors, and lesion characteristics are listed in the
Table
.
The clinical stage of the patient’s disease was classified according
to the categories defined by Rutherford and
Becker.8 The mean
length of the arterial segment treated by angioplasty was longer than
the mean lesion length determining indication for PTA (see
Table),
because angioplasty also included segments with moderate stenoses in
the adjacent proximal and distal region. Furthermore, in some patients,
several stenotic lesions with short segments of a nearly normal vessel
lumen in between were treated, and in these patients, PTA+BT was
performed for the whole length, including the normal
segments.
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PTA and BT Procedures
An ipsilateral anterograde puncture and a 6F
introducer sheath (Cordis Europe) were used in all procedures.
Angioplasty was performed with 5- or 6-mm balloon catheters (Smash,
Schneider Europe). The degree of residual stenosis immediately after
PTA (or the degree of recurrent stenosis in case of follow-up
arteriography) was determined by comparing the width of the contrast
column (the measurements were made with a ruler) at the point of
maximal diameter reduction within the dilated segment with that of an
unaffected arterial segment immediately proximal to the dilated
segment.
The region in which angioplasty was performed was marked with a radiopaque ruler, and movement of the table and angiographic unit was avoided to prevent parallax error. In patients randomized to further BT, the standard sheath was exchanged for a 55-cm 6F sheath (Brite Tip, Cordis Europe), which was advanced until its tip was 15 mm distal to the dilated segment. After placement of this sheath across the angioplastic site, a 5F closed-tip noncentered applicator (Lumencath Applicator Nucletron, which accommodated the radiation source inserted during the afterloading procedure) was inserted and placed 15 mm distal to the dilated segment. This catheter was equipped with a wire with markers at 1.0-cm intervals for exact measurement of the length of the angioplastic site. The sheath and the applicator were fixed to the patient to prevent movement relative to the lesion during transportation to the brachytherapy unit. The position of the 5F delivery catheter and the marked wire in relation to the target volume was verified by means of radiography before starting the afterloading procedure.
The BT procedure was performed by use of a remote high-dose-rate afterloading device as used in BT in general (micro Selectron, Nucletron). Treatment planning was performed with a computer-assisted standard dose calculation planning system (PLATO-BPS, version 13.2, Nucletron). A reference dose of 12 Gy was prescribed 3 mm from the source axis in the midplane of the applicator. (In case of ideal centering of the source in a vessel with a diameter of 5 mm, a dose of 15 Gy was calculated for the luminal surface, and a dose of 8 Gy was calculated for the adventitia. In case of decentering, a minimum dose of 9 Gy and a maximum dose of 44 Gy were calculated to the luminal surface. The corresponding doses to the adventitia were 6 and 12 Gy, respectively.) The length of the artery to be irradiated corresponded to the total length of the angioplastic site with an additional 1 cm at each end, which has been chosen as a safety margin.
After the treatment planning, the proximal end of the applicator was connected by means of a special 5F adapter to the afterloader. To ensure unimpeded placement of the active source, an inactive test wire (dummy wire) was placed. Then, an 192Ir source with a diameter of 1.1 mm and a mean activity of 200 GBq (150 to 366 GBq) was delivered. The mean irradiation time was 263 seconds (range 154 to 656 seconds).
Transportation to the BT unit and the irradiation protocol
prolonged the PTA procedure by 
30 minutes (range 25 to 55
minutes)
Treatment with 100 mg of aspirin per day was initiated at least 2 weeks before the intervention and was prescribed as long-term treatment. During the intervention, 5000 IU of standard heparin was administered, and further administration at a dosage of 1000 IU/h was started before transportation to the BT unit and was continued until the next morning.
Follow-Up
Follow-up examinations were performed the day after
PTA and at 1, 3, 6, 12, 18, and 24 months after PTA. Follow-up
examinations were assessment of symptoms, clinical examination, and
noninvasive laboratory testing, including (1) ankle-brachial arterial
pressure measurement with Doppler ultrasound to calculate the
ankle-brachial pressure index (ABI) and (2) color duplex ultrasound
(5-MHz linear-array color probe, model XP10, Acuson) of the
femoropopliteal segment during each follow-up visit except for the
visit at 1 month. The maximum peak systolic velocity in the dilated
region was determined and compared with the peak systolic velocity in
the preceding normal arterial segment. A focal increase in the peak
systolic velocity of at least 140% (corresponding to a peak velocity
ratio [PVR] of 2.4) was considered indicative of a stenosis of
>50% at that
site.10 If recurrent
stenosis was suspected on the basis of clinical or laboratory findings
(deterioration of the ABI by at least 0.15 from the maximum
postprocedural level, a PVR in the dilated segment of at least 2.4, or
both), intra-arterial angiography was performed with eventual further
PTA. According to the high sensitivity of color duplex ultrasound for
detection of >50% stenosis, control angiography was not mandatory in
the case of normal hemodynamic results, but with patient consent,
control angiography was also performed after at least 6 months in
patients without suspicion of restenosis. Noninvasive laboratory
testing, duplex ultrasound investigations, and angiographic follow-up
investigations were performed and analyzed by investigators without
knowledge of group randomization.
Primary Patency
The primary end point of the study was the patency of
the recanalized segment after 6 months. Restenosis was defined as an
angiographically verified stenosis of >50% narrowing of the luminal
diameter within the recanalized segment compared with the diameters of
normal segments of the vessel on the follow-up
angiogram.
Clinical Patency
Clinical success of the procedure was defined by
immediate improvement by at least 1 clinical category according to the
criteria defined by
Rutherford.8 Patients
with tissue damage had to move up at least 2 categories and reach the
level of claudication to be considered improved. Clinical patency is
defined by sustained improvement without further
intervention.
Target vessel revascularization was defined as further PTA
or surgical bypass of the target vessel that was required because of
the presence of 50% diameter stenosis of the target
lesion.
Statistical Analysis
For data storage and statistical analysis, SAS
software was used.11
The expected patency rate from PTA alone was, according to our own
institutional experience and according to data in the literature,
20% to 50% for patients with long-segment or recurrent
femoropopliteal
lesions.1 12 13
Otherwise, according to data from our own pilot
study7 and the
experience of a German
group,6 we could
expect an absolute improvement of the primary patency of at least 20%
to 30% by additional treatment with endovascular BT after angioplasty.
We assumed that a 30% absolute decrease in restenosis rate is of
important clinical relevance. To prove a 30% absolute difference
between these 2 treatment arms with a value of P<0.05
and a statistical power of 85%, 82 patients had to be entered into the
trial. To compensate for the dropout of patients lost to follow-up, we
intended to include at least 100 patients. With proper patient
enrollment, the inclusion of patients was to be stopped at the end of
August 1998.
The Kaplan-Meier method was used to calculate the survival
function, ie, the curve of the cumulative patency rate versus time. To
test whether there was a statistically significant difference between
survival curves (P<0.05), we used the log-rank test.
The 6-month patency rates were compared between the groups by
2 test.
The time of recurrence was judged by recurrence of symptoms, or for patients with asymptomatic recurrence, the date of the regular planned control was taken as the failure date. Patients who died without known recurrence were censored with the date of their last control.
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Results |
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TopAbstractIntroductionMethodsResultsDiscussionReferences |
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The irradiation procedure was technically feasible in all patients without complications. The patients experienced no adverse events.
The follow-up period was 12±6 (mean±SD) months. Follow-up information by clinical examination and noninvasive laboratory testing (measurement of ABI and duplex sonography) could be obtained in 108 patients. Control angiography was performed in 69 patients (64%), 37 in the PTA group and 32 in the PTA+BT group, after 9±5 months.
Five patients (4.4%) were lost to follow-up after hospital discharge (1 in the PTA group and 4 in the PTA+BT group). In 1 of these 5 patients, information could be obtained about death without knowledge concerning patency of the recanalized segment.
6-Month Patency
In 107 patients, information concerning the patency of
the recanalized segment could be obtained after 6 months (1 patient had
died before the 6-month control).
The overall recurrence rate was 29 (53.7%) of 54 in the PTA
alone group versus 15 (28.3%) of 53 in the PTA+BT group
(2 test,
P<0.05).
In the PTA group, 25 of 29 patients with recurrences
presented with restenosis, and 4 of the 29 patients presented with
reocclusion. Otherwise, in the PTA+BT group, none of the 15 patients
with recurrence had reocclusion. An angiographic example for restenosis
is given for each group in
Figure 1 and
Figure 2.
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Cumulative Patency
The cumulative patency rates
(Figure 3) of the recanalized segment, calculated by the
Kaplan-Meier method, at 12 months of follow-up were 35.3% in the PTA
group and 63.6% in the PTA+BT group (log-rank test,
P<0.005).
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Hemodynamic Results
Ankle-Brachial Index
The mean ABI increased from 0.50 (range 0.18 to 0.91)
in the PTA group and 0.51 (range 0.1 to 0.92) in the PTA+BT group
before PTA to 0.79 (range 0.40 to 1.13) and 0.85 (range 0.48 to 1.09),
respectively, the day after PTA.
Follow-up examinations demonstrated mean values of 0.77 (range 0.15 to 1.14) and 0.88 (range 0.47 to 1.20) in the PTA and PTA+BT groups, respectively, after 3 months and 0.74 (range 0.21 to 1.25) and 0.84 (range 0.27 to 1.25), respectively, after 6 months. (Values for patients with secondary interventions because of recurrence are not included.)
Peak Velocity Ratio
The mean PVR decreased from 7.3 (range 3.0 to 12.1) in
the PTA group and 6.3 (range 2.7 to 11.9) in the PTA+BT group before
PTA to 1.7 (range 1.05 to 2.2) and 1.7 (range 1.0 to 2.15),
respectively, the day after PTA. The mean follow-up values were 2.50
(range 1.0 to 10.6) and 1.93 (range 1.0 to 11.8), respectively, after 3
months and 3.05 (range 1.1 to 9.8) and 2.41 (range 1.0 to 9.9),
respectively, after 6 months. (Values for patients with secondary
interventions because of recurrence are not included. Furthermore, in
patients with occlusion, no PVR value can be calculated.)
Taking a cutoff value of 2.4 for the PVR to detect a
>50% stenosis, we could demonstrate a sensitivity of 97% compared
with angiography (see
Figure 4).
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Clinical Patency
The cumulative clinical patency rates (calculated by
the Kaplan-Meier method) at 12 months of follow-up were 51.9% in the
PTA group and 73.6% in the PTA+BT group, respectively (log-rank test,
P<0.05).
Reinterventions
Target lesion revascularization was performed during a
mean follow-up period of 12 months in 22 patients (in 20 patients by
further PTA and in 2 patients by bypass surgery) in the PTA group and
in 14 patients (all with PTA) in the PTA+BT group. None of the patients
had clinical or hemodynamic deterioration because of progression of
atherosclerosis at other sites of the treated leg. Otherwise, in 22
patients (9 in the PTA group and 13 in the PTA+BT group), angiography
was primarily performed because of symptoms of the contralateral leg,
and PTA in the contralateral leg was performed in 19 of these during
the follow-up period.
Complications
The examination of the puncture site by means of duplex
sonography the day after the intervention demonstrated a small
pseudoaneurysm in 2 patients (1 in the PTA group and 1 in the PTA+BT
group). Both were successfully treated by ultrasound-guided compression
therapy. Two further patients (1 in each group) had hematoma at the
puncture site with a drop in hemoglobin value between 2 and 3
g/dL.
Aneurysm formation was not observed in any patient by duplex sonography or angiography during a mean follow-up of 12 months. However, in 6 patients (1 in the PTA group and 5 in the PTA+BT group), a moderate ectasia (with a diameter of the vessel up to 9 mm) was observed in the treated segment.
Survival
During a mean follow-up of 12 months (range 6 to 24
months), 7 patients died (6.4% of the 109 patients with follow-up
information concerning survival), 6 in the PTA group and 1 in the
PTA+BT group. Five patients died from coronary heart disease, 1 died
from stroke, and 1 died from cancer.
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Discussion |
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TopAbstractIntroductionMethodsResultsDiscussionReferences |
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A poor long-term patency rate after PTA of longer femoropopliteal lesions was repeatedly reported,1 2 and complex and longer areas of stenosis may have a 6-month patency rate as low as 23%.1 Restenosis constitutes the most important problem after successful angioplasty. Therefore, angioplasty is not generally accepted for treatment of longer femoropopliteal lesions by many vascular clinical specialists. The present study group consisted of patients at particular risk of restenosis because they had longer de novo lesions (
5 cm) or because they had at least 1 previous episode of
recurrence.
Extensive animal
work4 and recently
published findings of studies in
humans5 6
have shown the feasibility of irradiation for the prevention of
restenosis. Despite the use of different animal models, different
arteries, and different isotopes with ß or 
radiation, there is a
remarkable consistency in the efficacy of endoluminal BT for inhibiting
neointimal hyperplasia.
Although the classic concept of restenosis suggests migration and proliferation of smooth muscle cells from the media,3 results of recent experiments demonstrate that mainly myofibroblasts in the adventitia proliferate during the first days after angioplasty and may migrate into the intima.14 This has implications for the BT protocol, because it is important to know definitely the target tissue. At this time, the target tissue for radiation effects is not definitely known, and various dose prescription points and doses have been used in ongoing trials.15 In the present study, a reference dose of 12 Gy was prescribed at 3 mm from the source axis, which corresponds to the inner intimal layer of the vessel. This is in accordance with the study of Böttcher et al.16 This group has used a dose of 12 Gy because of the lengthy experience and positive results with this dose in the prevention of keloids. Unlike the present study, their study used postangioplasty irradiation only in segments with stents and shorter lesion lengths of 4.5 to 14 cm (mean 6.7 cm).6
The dose used in the present study was in the lower range compared with the dose used in most coronary trials using gamma sources.15 In the Scripps Coronary Radiation to Inhibit Intimal Proliferation Post Stenting (SCRIPPS) trial, which was a double-blind randomized trial comparing a noncentered 192Ir source with a placebo source after angioplasty of restenotic stented coronary lesions, a relationship between efficacy and minimum dose exposure was observed, inasmuch as an adequate treatment effect required that a minimum dose of at least 8 Gy be delivered to the entire circumference of the adventitial border.17
Despite the overall significant reduction of recurrence
demonstrated in the present study, the remaining restenosis rate is
still high because we could not prevent restenosis in about one third
of our patients. As already mentioned, the dose used in our trial may
not be adequate for complete inhibition of neointimal hyperplasia.
Another important factor that can account for the observed restenoses
in the present study may be the dose inhomogeneity due to an eccentric
catheter position. Such poor centering of the source within the
arterial lumen may result in areas of both relative underdosage and
overdosage with respect to the prescribed dose. With long treatment
lengths, a noncentered catheter can often be eccentrically located at
various points along the vessel length. An eccentric plaque can further
accentuate this noncentering. In our experience, decentering of the
source with the technique applied was not uncommon, although some
centering may be achieved by the 5F radiation delivery catheter and the
6F sheath. Otherwise, source centering for emitters, such as
192Ir, is not as critical as it is for ß
emitters.18 New
catheters with centering capabilities have been designed and are used
in ongoing clinical trials. However, even if the source is perfectly
centered, dose asymmetries will continue to result from eccentrically
located plaques.
We did not observe an "edge effect" as reported in studies using BT after stent implantation or in studies with radioactive stents.19 This may be due to the use of a safety margin of 1 cm of irradiation surpassing the angioplasty length at each end.
There is anecdotal clinical evidence suggesting that radiation treatment may be associated with an increased rate of late thrombotic occlusion, which is due to delayed reendothelialization in balloon-injured irradiated vessels, particularly in newly stented vessels.20 This was not a problem in the present study, because in the case of recurrence, all patients in the BT group presented with restenosis, and no patient had thrombotic reocclusion.
Because there remains the question of whether radioactive therapy prevents the restenosis process or simply delays it, long-term studies are mandatory. Although short-term results have been promising, long-term efficacy and safety of this technique are not known. Recently, Teirstein et al21 reported in a small series that effectiveness of intracoronary BT was sustained over a 3-year period. Liermann et al6 also reported that the optimistic primary results have been confirmed by long-term results, with a range of follow-up of 4 to 68 months.
Limitations of the Present Study
The possible limitations according to dose (the
prescribed reference dose may not be adequate for complete inhibition
of neointimal hyperplasia) and to dose inhomogeneity (due to lack of a
centering device) have been discussed above.
Control arteriography was not performed in every patient.
However, color duplex sonography with measurement of the peak systolic
velocity and calculation of the PVR is a very sensitive method for the
detection of a reduction in luminal diameter of >50% in the
femoropopliteal region. Ranke et
al10 reported an
optimal cutoff value of 2.4 for the PVR to detect an angiographically
50% stenosis, and we could demonstrate, by use of this cutoff value,
a sensitivity of 97% to detect a >50% stenosis compared with
angiography (see
Figure 4
).
We did not perform quantitative angiography, as used in coronary interventions, because this kind of evaluation of the angiograms was not used in peripheral interventions until recently.
The patients and the interventionists were not blinded to the treatment arm. However, to avoid bias at follow-up, noninvasive laboratory testing and angiographic follow-up investigations were performed and analyzed by investigators without knowledge of group randomization. The study was limited to a single center.
In summary, this is the first randomized study to demonstrate the efficacy of endovascular BT for prophylaxis of restenosis after femoropopliteal PTA. However, the results of our trial must be confirmed by a double-blinded randomized multi-institutional study using an adequate centering device before the use of endovascular BT can be generally recommended for prophylaxis of restenosis after femoropopliteal PTA.
Received April 20, 2000; revision received July 14, 2000; accepted July 17, 2000.
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 T. Zeller Current state of endovascular treatment of femoro-popliteal artery disease Vascular Medicine, August 1, 2007; 12(3): 223 - 234. [Abstract] [PDF]
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 N. Diehm, I. Baumgartner, M. Jaff, D.-D. Do, E. Minar, J. Schmidli, C. Diehm, G. Biamino, F. Vermassen, D. Scheinert, et al. A call for uniform reporting standards in studies assessing endovascular treatment for chronic ischaemia of lower limb arteries Eur. Heart J., April 1, 2007; 28(7): 798 - 805. [Abstract] [Full Text] [PDF]
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 C. Klonaris, A. Katsargyris, A. Giannopoulos, and E. Bastounis Advances in Endovascular Treatment of Femoropopliteal Arterial Occlusive Disease Perspectives in Vascular Surgery and Endovascular Therapy, December 1, 2006; 18(4): 329 - 341. [Abstract] [PDF]
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 R. M. Wolfram, A. C. Budinsky, B. Pokrajac, R. Potter, and E. Minar Endovascular Brachytherapy for Prophylaxis of Restenosis after Femoropopliteal Angioplasty: Five-year Follow-up--Prospective Randomized Study Radiology, September 1, 2006; 240(3): 878 - 884. [Abstract] [Full Text] [PDF]
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 V. J. Yacyshyn, M. R. Thatipelli, R. J. Lennon, K. R. Bailey, A. W. Stanson, D. R. Holmes Jr, and P. Gloviczki Predictors of Failure of Endovascular Therapy for Peripheral Arterial Disease Angiology, August 1, 2006; 57(4): 403 - 417. [Abstract] [PDF]
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M. Schillinger, S. Sabeti, C. Loewe, P. Dick, J. Amighi, W. Mlekusch, O. Schlager, M. Cejna, J. Lammer, and E. Minar Balloon angioplasty versus implantation of nitinol stents in the superficial femoral artery. N. Engl. J. Med., May 4, 2006; 354(18): 1879 - 1888. [Abstract] [Full Text] [PDF]
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R. M. Wolfram, A. C. Budinsky, B. Pokrajac, R. Potter, and E. Minar Vascular Brachytherapy with 192Ir after Femoropopliteal Stent Implantation in High-Risk Patients: Twelve-month Follow-up Results from the Vienna-5 Trial Radiology, July 1, 2005; 236(1): 343 - 351. [Abstract] [Full Text] [PDF]
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R. M. Wolfram, A. C. Budinsky, B. Pokrajac, R. Potter, and E. Minar Endovascular Brachytherapy: Restenosis in de Novo versus Recurrent Lesions of Femoropopliteal Artery--The Vienna Experience Radiology, July 1, 2005; 236(1): 338 - 342. [Abstract] [Full Text] [PDF]
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E. Therasse, D. Donath, J. Lesperance, J.-C. Tardif, M.-C. Guertin, V. L. Oliva, and G. Soulez External Beam Radiation to Prevent Restenosis After Superficial Femoral Artery Balloon Angioplasty Circulation, June 21, 2005; 111(24): 3310 - 3315. [Abstract] [Full Text] [PDF]
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K. Goshima and J. L. Mills Sr De Novo Femoropopliteal stenoses: Endovascular Gamma Irradiation Following Angioplasty-Angiographic and Clinical Follow-up in a Prospective Randomized Controlled Trial Perspectives in Vascular Surgery and Endovascular Therapy, March 1, 2005; 17(1): 69 - 70. [Abstract] [PDF]
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E. Minar, M. Schillinger, K. Krueger, and K. Lackner Endovascular Irradiation after Femoropopliteal Angioplasty * Drs Krueger and Lackner respond: Radiology, December 1, 2004; 233(3): 935 - 937. [Full Text] [PDF]
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S. Sabeti, M. Schillinger, J. Amighi, C. Sherif, W. Mlekusch, R. Ahmadi, and E. Minar Primary Patency of Femoropopliteal Arteries Treated with Nitinol versus Stainless Steel Self-expanding Stents: Propensity Score-adjusted Analysis Radiology, August 1, 2004; 232(2): 516 - 521. [Abstract] [Full Text] [PDF]
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K. Krueger, M. Zaehringer, M. Bendel, H. Stuetzer, D. Strohe, M. Nolte, D. Wittig, R.-P. Mueller, and K. Lackner De Novo Femoropopliteal Stenoses: Endovascular Gamma Irradiation Following Angioplasty--Angiographic and Clinical Follow-up in a Prospective Randomized Controlled Trial Radiology, May 1, 2004; 231(2): 546 - 554. [Abstract] [Full Text] [PDF]
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 M. Schillinger, M. Exner, E. Minar, W. Mlekusch, M. Mullner, C. Mannhalter, F. H. Bach, and O. Wagner Heme oxygenase-1 genotype and restenosis after balloon angioplasty: a novel vascular protective factor J. Am. Coll. Cardiol., March 17, 2004; 43(6): 950 - 957. [Abstract] [Full Text] [PDF]
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M. Schillinger, W. Mlekusch, R. M. Wolfram, A. C. Budinsky, M. Exner, H. Rumpold, O. Wagner, B. Pokrajac, R. Potter, and E. Minar Endovascular Brachytherapy: Effect on Acute Inflammatory Response after Percutaneous Femoropopliteal Arterial Interventions Radiology, February 1, 2004; 230(2): 556 - 560. [Abstract] [Full Text] [PDF]
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P. S. Teirstein and S. King Vascular Radiation in a Drug-Eluting Stent World: It's Not Over Till It's Over Circulation, July 29, 2003; 108(4): 384 - 385. [Full Text] [PDF]
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R. Waksman and J. Weinberger Coronary Brachytherapy in the Drug-Eluting Stent Era: Don't Bury It Alive Circulation, July 29, 2003; 108(4): 386 - 388. [Full Text] [PDF]
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B. J. Pearce and J. F. McKinsey Current Status of Intravascular Stents as Delivery Devices to Prevent Restenosis Vascular and Endovascular Surgery, July 1, 2003; 37(4): 231 - 237. [Abstract] [PDF]
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M. Schillinger, M. Exner, W. Mlekusch, M. Haumer, H. Rumpold, R. Ahmadi, S. Sabeti, O. Wagner, and E. Minar Endovascular Revascularization Below the Knee: 6-month Results and Predictive Value of C-reactive Protein Level Radiology, May 1, 2003; 227(2): 419 - 425. [Abstract] [Full Text] [PDF]
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R. Bonvini, I. Baumgartner, D. D. Do, M. Alerci, J.-M. Segatto, P. Tutta, K. Jager, M. Aschwanden, E. Schneider, B. Amann-Vesti, et al. Late acute thrombotic occlusion after endovascular brachytherapy and stenting of femoropopliteal arteries J. Am. Coll. Cardiol., February 5, 2003; 41(3): 409 - 412. [Abstract] [Full Text] [PDF]
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M. Schillinger, M. Exner, W. Mlekusch, H. Rumpold, R. Ahmadi, S. Sabeti, M. Haumer, O. Wagner, and E. Minar Vascular Inflammation and Percutaneous Transluminal Angioplasty of the Femoropopliteal Artery: Association with Restenosis Radiology, October 1, 2002; 225(1): 21 - 26. [Abstract] [Full Text] [PDF]
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T. C. McCowan and M. L. Baker Brachytherapy: Hot or Not Radiology, August 1, 2002; 224(2): 323 - 324. [Full Text] [PDF]
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K. Krueger, P. Landwehr, M. Bendel, M. Nolte, H. Stuetzer, R. Bongartz, M. Zaehringer, G. Winnekendonk, A. Gossmann, R.-P. Mueller, et al. Endovascular Gamma Irradiation of Femoropopliteal de Novo Stenoses Immediately after PTA: Interim Results of Prospective Randomized Controlled Trial Radiology, August 1, 2002; 224(2): 519 - 528. [Abstract] [Full Text] [PDF]
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 A. Odurny Radiological Investigation and Treatment of the Critically Ischemic Limb--A Review International Journal of Lower Extremity Wounds, March 1, 2002; 1(1): 33 - 42. [Abstract] [PDF]
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G. Mozes and P. Gloviczki Adjuvant Therapy in Lower Extremity Revascularization: Prevention of Early and Intermediate Failures Perspectives in Vascular Surgery and Endovascular Therapy, January 1, 2002; 15(2): 161 - 180. [Abstract] [PDF]
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P. S. Teirstein and R. E. Kuntz New Frontiers in Interventional Cardiology: Intravascular Radiation to Prevent Restenosis Circulation, November 20, 2001; 104(21): 2620 - 2626. [Full Text] [PDF]
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R. M. Wolfram, B. Pokrajac, R. Ahmadi, C. Fellner, M. Gyongyosi, M. Haumer, R. Bucek, R. Potter, and E. Minar Endovascular Brachytherapy for Prophylaxis against Restenosis after Long-Segment Femoropopliteal Placement of Stents: Initial Results Radiology, September 1, 2001; 220(3): 724 - 729. [Abstract] [Full Text] [PDF]
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 J. M. Isner, P. R. Vale, J. F. Symes, and D. W. Losordo Assessment of Risks Associated With Cardiovascular Gene Therapy in Human Subjects Circ. Res., August 31, 2001; 89(5): 389 - 400. [Abstract] [Full Text] [PDF]
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D. W. Losordo and J. M. Isner Vascular endothelial growth factor-induced angiogenesis: crouching tiger or hidden dragon? J. Am. Coll. Cardiol., June 15, 2001; 37(8): 2131 - 2135. [Full Text] [PDF]
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P. S. Teirstein Fulfilling the Promise of Percutaneous Angioplasty Circulation, November 28, 2000; 102(22): 2674 - 2676. [Full Text] [PDF]
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