Successful Percutaneous Transluminal Angioplasty Research Articles

External beam radiotherapy fails to prevent restenosis after iliac or femoropopliteal percutaneous transluminal angioplasty: results of a prospective randomized double-blind study

Purpose Early restenosis is one of the major complications after successful percutaneous transluminal angioplasty (PTA), in main, as well as peripheral, arteries. The effectiveness of hypofractionated external beam radiotherapy (EBRT) as a prophylaxis for restenosis was examined in a prospective, randomized, double-blind, clinical trial. Methods and materials Forty-eight patients underwent sham RT and 47 were treated with daily RT in 3-Gy fractions, to a total dose of 21 Gy. The follow-up lasted for 12 months, and the examinations included pressure measurements and calculations of the ankle-brachial index or duplex sonography (“peak velocity ratio”). If restenosis was suspected, additional angiography was performed. Results No statistically significant difference was found between the treatment groups: sham RT 16 failures (33.3%) and EBRT group 21 failures (45.7%; p = 0.292). EBRT also showed no substantial effects on subgroups classified by the specific length of the lesion or in diabetic patients. Conclusion External beam radiotherapy does not prevent restenosis. A reduction in the failure rate >8% using fractionated EBRT with doses aimed at keloid prevention can be ruled out with a probability of 97.5%. Endovascular brachytherapy remains the preferred therapeutic method for achieving restenosis prophylaxis through RT.

Current Status of Intravascular Stents as Delivery Devices to Prevent Restenosis

The acute technical success of percutaneous transluminal angioplasty (PTA) has been improved with the use of intravascular stents. However, stent placement has led to the development of an increased myointimal hyperplastic response leading to late reduction in vessel lumen. Restenosis (> or =50% reduction in reference lumen diameter) rates for coronary angioplasty and stenting are reported between 20% and 50% at 1 year. Several studies are currently evaluating novel delivery of antiproliferative agents to prevent neointimal hyperplasia. The authors review the mechanism of neointimal hyperplasia as it relates to stent placement and discuss recent and ongoing trials evaluating intravascular brachytherapy and drug-eluting stent technology in the inhibition of restenotic lesions.

Endovascular revascularization below the knee: 6-month results and predictive value of C-reactive protein level.

To determine the association between pre- and postintervention serum C-reactive protein (CRP) levels and 6-month restenosis after endovascular treatment of atherosclerotic lesions in arteries below the knee. Eighty-nine patients with peripheral arterial disease underwent primary successful percutaneous transluminal angioplasty (PTA) of the distal popliteal, anterior tibial, posterior tibial, and fibular arteries. Six-month patency was evaluated with the ankle brachial index (ABI) and color-coded duplex ultrasonography (US). The association between restenosis and preintervention and 48-hour postintervention CRP levels was assessed with multiple logistic regression analysis. ABI improved from a preintervention median of 0.54 to a postintervention median of 0.75 (P <.001). The primary technical success rate was 94% (100 of 106). In 50 patients, a suboptimal technical result was achieved with 30%-40% residual stenosis at the dilated segment. The median ABI at 6 months was 0.65, and it was inversely correlated with preintervention (r = -0.27, P =.009) and 48-hour postintervention (r = -0.40, P <.001) CRP levels. With duplex US at 6 months, restenosis (> or =50%) occurred in 36 patients. Patients with a preintervention CRP level of 0.23-0.92 mg/dL (2.3-9.2 mg/L) had a 3.7-fold increased adjusted risk for restenosis (P =.05); patients with a preintervention CRP level greater than 0.92 mg/dL (9.2 mg/L) had a 4.7-fold increased adjusted risk (P =.03). Postintervention CRP values greater than 2.42 mg/dL (24.2 mg/L) were associated with a 10.7-fold adjusted risk for restenosis (P =.002). Suboptimal PTA result was the only other parameter associated with an increased risk for restenosis (odds ratio, 3.7; P =.03). Pre- and postintervention CRP levels were associated with restenosis after PTA of the distal popliteal and tibioperoneal arteries, which indicates that inflammation plays a crucial role in the pathophysiology of this process.

The diagnostic value of levovist in Doppler imaging of visceral arteries in patients with abdominal angina before and after angioplasty

Purpose: To assess the diagnostic value of Levovist in the ultrasound imaging of visceral arteries in patients with clinical symptoms of abdominal angina, before and after percutaneous transluminal angioplasty (PTA). Material and method: During a 12-month period (2000/2001) five patients with visceral arterial stenoses had ultrasound examinations and a subsequent PTA procedure. Indications for ultrasound examination were abdominal angina symptoms persisting for 3–5 years, (postprandial abdominal pain, diarrhea, and vomiting). In all patients ultrasound examinations were performed using color and spectral Doppler before and after Levovist injections. Color Doppler images and maximum blood flow velocity in stenosed visceral arteries were assessed. Patients underwent control Doppler examinations with Levovist injections to assess the effect of PTA. Results: In three patients conventional Doppler examination did not allow proper evaluation of visceral arteries, because of weak color and spectral Doppler signal and in two remaining patients visceral arteries were not visualized at all. In all five patients strong enhancement of color and spectral Doppler signal was observed after Levovist administration. In all these cases a hemodynamically significant stenosis was diagnosed: coeliac trunk-2 and superior mesenteric artery-3. PTA was performed successfully in these patients. In one of them ultrasound examination done before Levovist injection allowed good visualization of treated SMA and showed good PTA result. In the remaining four patients Doppler examination with the use of Levovist demonstrated visceral arteries well and confirmed successful PTA procedures. Conclusions: The use of Levovist makes the diagnostic efficiency of Doppler examinations much higher. In most cases it allows an unequivocal diagnosis of visceral artery stenosis in patients with abdominal angina symptoms. The Doppler examination with the use of Levovist is the method of choice in follow-up after PTA.

Interleukin-1 cluster combined genotype and restenosis after balloon angioplasty.

The interleukin-1 system is fundamentally involved in the pathogenesis of restenosis after percutaneous transluminal angioplasty (PTA). In order to further define the clinical impact of genetic variation in this potent proinflammatory pathway we investigated the joint effects of two single nucleotide polymorphisms in the interleukin-1 beta gene [IL-1B(-511) and IL-1B(+3954)] and a variable number tandem repeat polymorphism in intron 2 of the interleukin 1 receptor antagonist gene (IL-1RN VNTR) on postintervention inflammation and occurrence of restenosis in 183 consecutive patients who underwent successful femoropopliteal PTA. C-reactive protein (CRP) and serum amyloid A (SAA) were determined pre- and 48 hours postintervention. Patients were followed up to 12 months for the occurrence of postangioplasty restenosis (> or = 50%). When analyzed separately, none of the polymorphisms was associated either with inflammation or restenosis. However, when the IL-1B (-511) and the IL-1RN VNTR genotypes were combined, a highly significant relationship was observed: Non-carriers of the two repeat allele of the IL-1RN VNTR (IL-1RN*2) who were heterozygous and homozygous for the IL-1B (-511)T allele exhibited a gradually increased inflammatory response and a higher restenosis risk. In contrast, carriers of the IL-1RN*2 and the IL-1B (-511)T allele showed a significantly better outcome. This remarkable gene dose-dependent association emphasizes the advantage of considering combinations of genetic markers rather that isolated polymorphisms in the analysis of multifactorial vascular disease.

Renal Artery Stenosis Presenting with Status Epilepticus: A Report of One Case

In children, renal artery stenosis is an uncommon but important cause of secondary hypertension. In this report, the authors describe a 5‐year‐old boy with no history of seizures who experienced status epilepticus. Postictal blood pressure, relative hypotension, was misinterpreted as normal on the day of admission. Two days later, his blood pressure rose gradually and peripheral plasma renin activity showed more than 1,700 μU/mL. Magnetic resonance angiography suggested renal artery stenosis. After successful percutaneous transluminal angioplasty, the patient was seizure‐free and had well‐controlled blood pressure. This case describes renal artery stenosis present with status epilepticus, and emphasizes the importance of serial measurements of blood pressure in children.

The usefulness of transcutaneous oximetry in assessing the success of percutaneous transluminal angioplasty

Objective: to identify whether monitoring transcutaneous oxygen pressure (TcpO2) can provide an objective method of assessing the results of PTA. Materials and Methods: fifty-seven patients (39 Fontaine stage II, 18 stage III or IV) had ABI, TcpO2 at rest (stages III and IV) or during exercise (stage II) and total work capacity of the leg (stage II) measured before, 24–48 h, 2 and 6 weeks after PTA. Results: a significant increase of ABI in both groups of patients was detected immediately after successful PTA. TcpO2 measured on the foot at rest increased in stages III and IV patients immediately after PTA (from 14 (IQR)18 to 25 (IQR)32 mmHg, p < 0.05) and again after 6 weeks in comparison to follow up two (from 25 (IQR)32 to 35 (IQR)21 mmHg, p < 0.05). In patients in stage II TcpO2 decreased in a typical fashion during exercise. Total oxygen drop was most evident before treatment (352 (IQR)458 s mmHg) and decreased significantly immediately after PTA (148 (IQR)175 s mmHg, p < 0.001). Conclusions: TcpO2 measurement is an useful method for investigating the success of PTA. While the macrocirculation improves immediately after successful recanalisation, complete normalisation of the microcirculation may take some weeks, especially stages III and IV disease.

Vascular inflammation and percutaneous transluminal angioplasty of the femoropopliteal artery: association with restenosis.

To determine the association of pre- and postprocedural serum levels of C-reactive protein (CRP), serum amyloid A (SAA), and fibrinogen at 6-month evaluation of restenosis after percutaneous transluminal angioplasty (PTA) of the femoropopliteal artery. In a prospective cohort study, 172 consecutive patients with peripheral artery disease of Fontaine stage IIa, IIb, or III who underwent successful PTA of the superficial femoral and popliteal arteries were included. Patency at 6 months was evaluated by using oscillography, ankle-brachial index, and color-coded duplex ultrasonography. The association of restenosis and CRP, SAA, and fibrinogen levels at baseline, 24 hours, and 48 hours after intervention was assessed by means of multivariate analysis with adjustment for known risk factors for restenosis. Restenosis was found in 56 patients (33%) within 6 months. CRP values at baseline (adjusted odds ratio, 2.2; 95% CI: 1.1, 4.2) and 48 hours after intervention (adjusted odds ratio, 2.3; 95% CI: 1.6, 3.1) were independently associated with 6-month restenosis. SAA and fibrinogen values at any time interval were not significantly associated with patency in the multivariate models. The extent of vascular inflammation as measured by means of acute-phase reactants before and after PTA of the femoropopliteal artery is associated with 6-month restenosis. Baseline and 48-hour CRP levels were independent predictors of postangioplasty outcome.

Coronary artery bypass grafting with left internal mammary artery and right gastroepiploic artery, with and without bypass

Background. Total arterial and off-pump revascularization are increasingly used in coronary artery bypass grafting. This study describes our experience with the exclusive use of both left internal thoracic artery and gastroepiploic artery by means of a median sternotomy, with and without cardiopulmonary bypass, in a subgroup of patients with two-vessel disease. Methods. From January 1995 to July 2000, 171 consecutive patients were reviewed in a prospective database. Ninety-one patients underwent coronary artery bypass grafting without cardiopulmonary bypass (group A), and 80 patients were operated on under cardiopulmonary bypass with aortic cross-clamp and cardioplegia (group B). Results. Patient data were similar in both groups except for the Euroscore (mean; 3.4 ± 6.1, group A versus 2.5 ± 4.5, group B; Euroscore > 6: 26.4%, group A versus 10%, group B; p < 0.05) and ejection fraction (mean, 54.6% ± 15.8%, group A versus 63.1% ± 12.7%, group B; p < 0.001). Severe aortic calcification was present in 6 group A patients, versus no patient in group B. Operative time was shorter in group A (185 versus 213 minutes, p < 0.0001), with less distal anastomoses (2.26 versus 2.5, p < 0.05). Conversion to cardiopulmonary bypass occurred in 1 patient, who was excluded from the study. Bleeding was higher in group A (852.6 ± 288 mL versus 712.4 ± 274 mL, p < 0.05), but transfusion was similar in both groups. Atrial fibrillation, postoperative inotropic support, and hospital stay were similar in both groups. Myocardial infarction was less frequent in group A (1 versus 4). Postoperative intraaortic balloon pump was used in 2 patients (group B). One patient died (group A) and 1 had an embolic stroke (group B). After discharge, 2 more patients died (group A, day 91; group B day 141), and 1 patient suffered an embolic stroke (group B). One patient in each group presented with dysfunction of the gastroepiploic artery graft requiring successful percutaneous transluminal angioplasty on the right posterolateral artery. Conclusions. These results suggest that off-pump coronary artery bypass grafting using the left internal thoracic artery and gastroepiploic artery is safe even in high-risk patients. This approach allows an absolute no-touch technique of the aorta.

Angioplasty of the innominate artery in 89 patients: experience over 19 years.

To assess retrospectively the success of percutaneous transluminal angioplasty (PTA) in treating innominate artery stenoses and occlusions in a large series of patients with long-term follow-up results. In symptomatic (upper limb claudication, transient ischemic attack, vertebrobasilar insufficiency) patients with high-degree (>60%) stenosis, innominate artery PTA was performed. Long-term follow-up was undertaken by blood pressure measurements on both arms as well as subclavian, right common carotid and right vertebral duplex scan. Between 1981 and 1999, the primary success rate of 89 innominate artery PTA (84 stenoses, 5 occlusions) was 96.4%. Complications included one left occipital lobe infarction (2%), two puncture-site thromboses (3%) and four transient ischemic attacks (6%). Two patients with restenosis were successfully treated with re-PTA. Cumulative primary patency was 98 +/- 2% at 6 months, 93 +/- 4% at 16-117 months; secondary patency was 100% at 6 months, 98 +/- 2% at 12-117 months. Sixty-one percent of the patients became symptomless, 32% improved, 7% showed no improvement. Angioplasty of the innominate artery has been proven to be safe and effective on a large series of patients. For innominate artery stenosis and short occlusion, PTA should be the treatment of choice.

Cardiovascular risk factors do not predict clinically defined restenosis after percutaneous transluminal angioplasty for lower limb ischemia.

The purpose of this study was to evaluate risk factors predicting restenosis and primary patency after percutaneous transluminal angioplasty. Follow-up data (including cardiovascular risk factor scores according to SCVIR criteria, preinterventional and postinterventional clinical data and patient history) of all patients who underwent successful percutaneous transluminal angioplasty for lower limb ischemia were analyzed retrospectively and patients, relatives, or referring physicians underwent a telephone interview. Patients with incomplete follow-up data were examined by means of a clinical examination, including Doppler measurements and treadmill test. Additionally all angiograms were evaluated to calculate lesion length, number of treated lesions, lesion type (SCVIR score), and runoff. The outcome was categorized into four groups: early recurrence (< 1 month, group I), mean recurrence (1-6 months, group II), late recurrence (>6 months, group III), and no recurrence (group IV). According to common concepts group I was defined as early (thrombotic) reocclusion, group II as clinically defined restenosis, and group III as progression of atherosclerosis. One hundred thirty-seven patients underwent percutaneous transluminal angioplasty of 148 extremities. The groups differ significantly only with respect to a higher diabetes score for group I in comparison to group IV (p=0.002, Kruskal-Wallis test), and a worse runoff of group I compared with group IV (p =0.008). There was a trend toward a higher diabetes score for group II in comparison to group IV (p = 0.014). There were no differences with regard to hyperlipemia, hypertension, and tobacco use between patient groups. Mean primary patency was 436 days. Predictors for lower patency rates were diabetes mellitus (p<0.001), runoff (p=0.005), and number of treated lesions (p=0.007) in a stepwise, multiple regression analysis. Patients with clinically defined restenosis showed no specific risk factor profile in this study. Predictors for lower primary patency were diabetes mellitus, number of treated lesions, and runoff.

Restenosis after percutaneous transluminal angioplasty in the femoropopliteal segment: the role of inflammation.

To determine the value of baseline C-reactive protein (CPR), fibrinogen, and white blood cell (WBC) counts in predicting 1-year patency after percutaneous transluminal angioplasty (PTA) in the femoropopliteal segment. In a retrospective cohort study, 168 consecutive patients (103 men; median age 70 years, interquartile range 61-77) who underwent successful PTA of the femoral and/or popliteal arteries were analyzed. Twelve-month patency was evaluated using oscillography, ankle brachial index, duplex sonography, and angiography. The predictive value of inflammatory markers was assessed in a multivariate model controlling for cardiovascular risk factors, technical success, and hemodynamic factors. Transient WBC elevation was found 6 hours after PTA, but this returned to baseline after 24 hours. Fibrinogen was elevated at 24 hours. Duplex scanning disclosed restenosis in 66 (39%) patients within the first 12 months after PTA. Only residual postdilation stenosis (> or = 30%) in the target segment (odds ratio 3.6, p=0.001) and baseline CRP levels (odds ratio 4.2, p=0.02) were independent predictors of outcome; neither WBC counts nor fibrinogen levels at any time point was associated with restenosis. Primary technical success and postinterventional hemodynamic flow at the dilated segment seem to be more important for intermediate-term patency than atherogenic risk factors. The predictive value of preprocedural serum CRP levels on restenosis should be further investigated.

Intravascular Radiation Therapy after Balloon Angioplasty of Narrowed Femoropopliteal Arteries to Prevent Restenosis: Results of the PARIS Feasibility Clinical Trial

To conduct a feasibility study to assess the feasibility, safety, and outcome of endoluminal gamma radiation therapy after balloon angioplasty of superficial femoral artery (SFA) lesions. Forty patients with claudication were enrolled in the study and underwent percutaneous transluminal angioplasty (PTA) of SFA lesions with a mean lesion length of 9.8 cm +/- 3.0 and a mean reference vessel diameter of 5.2 mm +/- 3.1. After successful PTA, a segmented centering balloon catheter was positioned to cover the PTA site. The patients were then transported to the radiation oncology suite and treated with a microSelectron HDR afterloader with use of an Ir-192 source with a prescribed dose of 14 Gy, 2 mm into the vessel wall. Ankle-brachial index (ABI) and Rutherford score were evaluated at 1, 6, and 12 months after the procedure and angiographic follow-up was conducted at 6 months. Radiation was delivered successfully to 35 of 40 patients. There were no procedural complications. Exercise and rest ABI were higher at 1 year (0.72 +/- 0.26 and 0.89 +/- 0.18, respectively) compared to baseline (0.51 +/- 0.25 and 0.67 +/- 0.17, respectively). Maximum walking time on a treadmill increased from 3.41 min +/- 2.41 to 4.43 min +/- 2.49 at 30 days and was 4.04 min +/- 2.8 at 12 months. The angiographic binary restenosis rate at 6 months was 17.2% and the clinical restenosis rate at 12 months was 13.3%. There were no angiographic or clinical adverse events related to the radiation therapy. Intraarterial radiation after PTA of SFA lesions with use of high-dose rate gamma radiation is feasible and safe. The angiographic and clinical improvements are sustainable at 1 year and represent a potent antirestenotic therapy for the treatment of narrowed peripheral arteries.

Usefulness and limits of distal echo-Doppler velocimetric indices for assessing renal hemodynamics in stenotic and non-stenotic kidneys.

Distal echo-Doppler velocimetric indices are widely used for revealing the presence of a renal artery stenosis but there is scarce information as to whether they reflect the renal hemodynamics in stenotic and nonstenotic kidneys. We evaluated the pulsatility and resistive indices (PI and RI), acceleration (A) and acceleration time (At) and correlated their values with those of effective renal plasma flow (ERPF), glomerular filtration rate (GFR), renal vascular resistance (RVR) and filtration fraction (FF) estimated by single kidney scintigraphy in 24 kidneys with 70-95% renal artery stenosis (atherosclerotic n = 17, fibromuscular n = 7) and in 27 non-stenotic kidneys (11 contralateral to renal artery stenosis and 16 of patients with essential hypertension). In patients with stenotic kidneys, these measurements were repeated within 7 days after a successful percutaneous transluminal renal angioplasty (PTRA) (in 11 arteries performed in combination with stent implantation). Prior to dilation we found that the stenotic kidneys had significantly lower values of ERPF, GFR and higher RVR than the non-stenotic kidneys and that these hemodynamic alterations were associated with those, also statistically significant, of the four velocimetric indices. In non-stenotic kidneys, there were highly significant relationships between PI and ERPF, and RVR (r = -0.68 and 0.81 respectively P < 0.01); similar relationships were found for RI (r = -0.67 and 0.78 P < 0.01) whereas no such correlations were found between these two velocimetric indices and GFR and FF; also no correlations were found between A and Atand ERPF, GFR, RVR and FF. In stenotic kidneys no significant correlations were found between any of the velocimetric and the hemodynamic indices. Renal artery dilation induced clear cut increments in ERPF, GFR and reduction in RVR in post-stenotic kidneys, which were associated with normalization of all four velocimetric indices. No relationships were observed between the renal hemodynamic and the velocimetric changes induced by dilation; however in post-stenotic kidneys the relationships between PI and RI, ERPF and RVR were restored as in nonstenotic kidneys. These data indicate that PI and RI can be used to assess ERPF and RVR both in non-stenotic and post-stenotic kidneys; however, none of the velocimetric indices examined in this study can provide valid informations on the renal hemodynamics of stenotic kidneys and on their changes induced by PTRA.

Renal Arterial Stenosis in Renal Allografts: Retrospective Study of Predisposing Factors and Outcome after Percutaneous Transluminal Angioplasty

To determine the predisposing factors to transplant renal arterial stenosis (TRAS) and assess the outcome of percutaneous transluminal angioplasty (PTA) as the primary treatment. Of 831 renal allograft recipients (584 cadaveric, 247 living related) between January 1991 and December 1998, 72 had hypertension and/or renal dysfunction. All 72 underwent arteriography, and their medical charts were retrospectively reviewed. Prevalence of TRAS was 3.1% (26 of 831). Technical success rate of PTA was 94% (16 of 17), and clinical success rate was 82% (14 of 17). Those with renal dysfunction had a mean pre-PTA creatinine value of 2.6 mg/dL (230 micromol/L) +/- 0.5 (SD) versus a 1-week post-PTA value of 1.7 mg/dL (150 micromol/L) +/- 0.3 (P <.001). Of those with hypertension, all but one had substantial improvement in mean diastolic blood pressure. At 26.9 months mean follow-up in 16 patients with successful PTA, two stenoses reoccurred, and two grafts were lost to chronic rejection. TRAS was present in 14 of 45 end-to-side anastomoses and 12 of 27 end-to-end anastomoses (P =.31), and TRAS was more prevalent in cadaveric grafts (24 of 584) than in living related grafts (two of 247). In cadaveric grafts, the mean cold ischemia time was 29.0 hours +/- 6.9 in those with TRAS (n = 24), as compared with 25.5 hours +/- 8.1 in those with no TRAS (n = 39; P = .35). Seven of 17 patients with acute rejection and six of 35 with chronic rejection had TRAS. Primary treatment of TRAS with PTA has good intermediate-term results. TRAS is more prevalent in cadaveric allografts with long cold ischemia time.

Hyperperfusion Syndrome of the Left Hand after Percutaneous Transluminal Angioplasty and Stent Placement in a Subclavian Artery Stenosis

PERCUTANEOUS transluminal angioplasty (PTA) has been described as an effective and safe procedure for treatment of symptomatic subclavian artery stenosis. The complication rate is low, the most frequent complication being embolism to the vertebral and digital arteries (1–5). Hyperperfusion syndrome (HS) and hyperemia are well known in reconstructive arterial surgery in chronic arterial occlusive disease, in particular carotid endarterectomy and bypass surgery of the lower limb (6–9). This phenomenon was also described after PTA of carotid and superficial iliac arteries, respectively (10,11). Clinical symptoms regarding the lower limb consist of unspecific swelling developing between day 1 and 7 after PTA. Clinical symptoms in PTA of carotid arteries develop from increased blood flow and present as headache and vomiting. We report a case of HS of the left hand and fingers after successful PTA and stent placement in a symptomatic highgrade stenosis of the subclavian artery.

Combined Iliac Angioplasty and Infrainguinal Revascularization Surgery Are Effective in Diabetic Patients with Multilevel Arterial Disease

The success of percutaneous transluminal angioplasty (PTA) in the treatment of common and external iliac atherosclerotic lesions has been established for the general population. However, several studies have suggested that the presence of diabetes may reduce the effectiveness of iliac angioplasty, particularly in the setting of limb-threatening ischemia requiring concomitant lower extremity revascularization. This study compared the results of iliac artery PTA performed in conjunction with infrainguinal bypass for limb-threatening ischemia for diabetic (DM) and nondiabetic (non-DM) patients. Between 1991 and 2000, 159 PTA were performed in 126 patients (DM = 99/79%, non-DM = 27/21%) in conjunction with subsequent infrainguinal bypass for limb-threatening ischemia (gangrene = 42%, ulcer = 36%, rest pain = 22%). These patients were followed prospectively using a computerized vascular registry. Stents were placed in 34 (21.4%) cases for suboptimal angioplasty results. In this study the combined use of standard surgical and endoluminal modalities for the treatment of multilevel arterial occlusive disease resulted in excellent cumulative patency and limb salvage rates. The presence of diabetes did not alter these favorable results. Multimodal vascular therapy may be used effectively in diabetic patients with limb-threatening ischemia due to multiple levels of arterial occlusion.

Endogeneous fibrinolysis and restenosis of peripheral arteries after percutaneous transluminal angioplasty

To assess the role of the fibrinolytic system in the pathogenesis of restenosis after percutaneous transluminal angioplasty (PTA) of peripheral arteries, 166 consecutive patients with peripheral atherosclerotic disease, ranging from 36 to 86 years old (median = 60), who had undergone successful PTA, were followed for 1 year. Tissue plasminogen activator (t-PA) and plasminogen activator inhibitor type 1 (PAI-1) antigens were determined before PTA and at 3, 6 and 12 months after, while t-PA activity, PAI-1 activi ty, fibrinogen, plasminogen, euglobulin clot lysis time anda2-antiplasmin were determined at 3 months after PTA. There were no significant differences in fibrinolytic parameters between patients with patent (121 patients – 73%) and those with restenosed (45 patients – 27%) arteries. Restenosis was more common in patients with poor outflow (17 out of 44 patients) than with good outflow (28 out of 122 patients;P< 0.05), with pre-existent occlusion (27 out of 93 patients) than with preexistent stenosis (17 out of 73 patients;P< 0.05), and with symptoms lasting longer than 6 weeks (35 out of 108 patients) than with symptoms lasting less (10 out of 58 patients;P< 0.05). We concluded that measured fibrinolytic parameters were not related to post-PTA restenosis, suggesting that the endogenous fibrinolytic system, estimated in peripheral blood, does not influence the development of restenosis in a peripheral artery.

Angiotensin converting enzyme DD genotype affects the changes of plasma plasminogen activator inhibitor-1 activity after primary percutaneous transluminal coronary angioplasty in acute myocardial infarction patients.

Angiotensin converting enzyme (ACE) DD genotype, and plasminogen activator inhibitor (PAI-1) 4G/4G genotype have been reported to affect PAI-1 activity in control subjects and atherosclerotic patients, but no data are available on the influence of angiotensin II type 1 receptor (AT1R) A1166C polymorphism on the inhibitor levels. The degree of fibrinolytic activation after percutaneous transluminal coronary angioplasty (PTCA) has been found to affect the risk of restenosis. The aim of this study was to investigate the possible influence of ACE I/D, AT1R A1166C, and PAI-1 4G/5G polymorphisms on the changes of PAI-1 activity after primary successful percutaneous transluminal angioplasty. In 29 consecutive acute myocardial infarction patients, undergoing primary successful angioplasty, genotyping of ACE I/D, AT1R A1166C, and PAI-1 4G/5G polymorphisms was performed by polymerase chain reaction and restriction fragment length polymorphism analysis, and PAI-1 plasma activity (chromogenic method) was assessed before and after angioplasty. Following angioplasty, PAI-1 activity increased in 10 of 29 patients and decreased or remained unchanged in 19 of 29. ACE DD genotype was significantly (P = 0.04) associated with an increase of PAI-1 activity post angioplasty (OR DD/ID+II = 6.5, CI 95% 4.83-8.22). Whereas no effect of PAI-1 4G/5G and AT1R A1166C polymorphisms on PAI-1 response to angioplasty was demonstrated, these data suggest that renin-angiotensin system genes are involved in the regulation of the fibrinolytic response to balloon injury, possibly affecting angiotensin converting enzyme activity. This interaction between the renin-angiotensin system and hemostasis may be a mechanism by which ACE DD genotype affects the risk of restenosis after percutaneous transluminal angioplasty.

Intraarterial 192Ir high-dose-rate brachytherapy for prophylaxis of restenosis after femoropopliteal percutaneous transluminal angioplasty: the prospective randomized Vienna-2-trial radiotherapy parameters and risk factors analysis

Purpose: The aim of the Vienna-2-trial was to compare the restenosis rate of femoropopliteal arteries after percutaneous transluminal angioplasty (PTA) with or without intraarterial high-dose-rate (HDR) brachytherapy (BT) using an 192Ir source. Materials and Methods: A prospective, randomized trial was conducted from 11/96 to 8/98. A total of 113 patients (63 men, 50 women), with a mean age of 71 years (range, 43–89 years) were included. Inclusion criteria were ( 1) claudication or critical limb ischemia, ( 2) de-novo stenosis of 5 cm or more, ( 3) restenosis after former PTA of any length, and ( 4) no stent implantation. Patients were randomized after successful PTA for BT vs. no further treatment. A well-balanced patient distribution was achieved for the criteria used for stratification, as there were “de-novo stenosis vs. restenosis after former PTA,” “stenosis vs. occlusion,” “claudication vs. critical limb ischemia” and above these for “diabetes vs. nondiabetes.” PTA length was not well balanced between the treatment arms: a PTA length of 4–10 cm was seen in 19 patients in the PTA alone group and in 11 patients in the PTA+BT group, whereas a PTA length of greater than10 cm was seen in 35 patients and 42 patients, respectively. A dose of 12 Gy was prescribed in 3-mm distance from the source axis. According to AAPM recommendations, the dose was 6.8 Gy in 5-mm distance (vessel radius + 2 mm). Primary endpoint of the study was femoropopliteal patency after 6 months. Results: PTA and additional BT were feasible and well tolerated by all 57 pts in this treatment arm. No acute, subacute, and late adverse side effects related to BT were seen after a mean follow up of 12 months (6–24 months) in 107 patients (PTA n = 54; PTA+ BT n = 53). Crude restenosis rate at 6 months was in the PTA arm 54% vs. 28% in the PTA + BT arm (χ 2 test; p < 0.013). Actuarial estimate of the patency rate was at 6 months 45% vs. 72% ( p < 0.004). Comparison of restenosis rates for the different subgroups with risk factors (restenosis after former PTA, occlusion and PTA length >10 cm) showed significant decrease of the restenosis rate, if BT was added. Significant reduction was not achieved in diabetes patients. Conclusion: BT after femoropopliteal PTA is feasible and a safe therapeutic option. No BT related morbidity was observed. A significant reduction of the restenosis rate was obtained in the PTA+BT arm. Subgroup analysis showed significant decrease of restenosis rate in the subgroups with restenosis after former PTA, occlusion and PTA length of greater than 10 cm. With dose escalation and reduction of dose variation by a centering device a further significant decrease of restenosis rate can be expected.