RESUMEN
PURPOSE: This follow-up study was designed as a reopen of the completed Freeway Stent Study and collected mortality and clinical outcome data for at least 5 years after enrollment to evaluate long-term patient safety and treatment efficacy. The primary study enrolled 204 patients with stenosis or occlusion in the superficial femoral artery and proximal popliteal artery. Patients were randomized to primary nitinol stenting followed by standard PTA or primary nitinol stenting followed by FREEWAY™ paclitaxel-eluting balloon PTA. METHODS: Previous patients were recontacted by phone or during a routine hospital visit, and medical records were reviewed. Vital and clinical status information was collected. RESULTS: No increased late mortality was observed at 5 years, with an all-cause mortality rate of 12.0% in the FREEWAY drug-eluting balloon group versus 15.0% in the non-paclitaxel PTA group. No accumulation of any cause of death was observed in either group, nor was there any correlation with the dose of paclitaxel used. Freedom from clinically driven target lesion revascularization at 5 years was significantly higher in the FREEWAY drug eluting balloon group (85.3%) compared to standard PTA group (72.7%) Log-rank p = 0.032. CONCLUSION: The safety results presented support the recent conclusions that the use of paclitaxel technology does not lead to an increase in mortality. At the same time, the efficacy results clearly demonstrate that the potential benefits of drug-eluting balloon treatment are maintained over a 5-year period.
Asunto(s)
Aleaciones , Angioplastia de Balón , Enfermedad Arterial Periférica , Humanos , Estudios de Seguimiento , Angioplastia de Balón/métodos , Arteria Femoral , Arteria Poplítea , Resultado del Tratamiento , Stents , Paclitaxel , Enfermedad Arterial Periférica/terapiaRESUMEN
PURPOSE: The prospective randomized multicenter Freeway study evaluated the possible hemodynamic and clinical benefits of primary stent insertion followed by percutaneous transluminal angioplasty (PTA) with drug-eluting balloons (DEB) over post-stent insertion PTA with standard balloons in the treatment of symptomatic femoropopliteal arteriosclerotic lesions. METHODS: In total, 204 patients in 13 centers in Germany and Austria were enrolled and randomized to primary stenting followed by either FREEWAY™ drug-eluting balloon or standard PTA balloon angioplasty. The primary endpoint was the rate of clinically driven target lesion revascularization (TLR) at 6 months; the secondary endpoints include TLR rate at 12 months and primary patency, shift in Rutherford classification, ankle-brachial index (ABI) and major adverse events (MAE) at 6 and 12 months. Lesion characteristics and vessel patency were analyzed by an independent and blinded corelab. RESULTS: At 6-month and 12-month follow-up, TLR rate was lower in the DEB arm compared to standard PTA but did not reach statistical significance (4.1% vs. 9.0% p = 0.234 and 7.9% vs. 17.7% p = 0.064, respectively). Primary patency was significantly better for patients treated with the DEB at 6 months (90.3% vs. 69.8% p = 0.001) and 12 months (77.4% vs. 61.0% p = 0.027). Improvement in Rutherford classifications was likewise significantly better for patients in the DEB group at 6 (94.9% vs. 84.3% p = 0.027) and 12 months (95.5% vs. 79.9% p = 0.003). The percentage of patients with an improved ABI of 1.0-1.2 was significantly higher in the DEB group compared to the PTA group at 6 months (55.3% vs. 35.3%; p = 0.015) but without significant difference at 12 months (48.2% vs. 32.9%; p = 0.055). At 6 months, rate of major adverse events (MAE) was 1% in both arms, and at 12 months 2.2% for the DEB and 3.8% for the PTA group. CONCLUSION: The Freeway Stent Study shows that the usage of DEB as a restenosis prophylaxis seems to be safe and feasible. The 12-month follow-up results give a clear sign in favor of the DEB group.
Asunto(s)
Aleaciones/administración & dosificación , Angioplastia de Balón/métodos , Stents Liberadores de Fármacos , Arteria Femoral/fisiopatología , Placa Aterosclerótica/terapia , Arteria Poplítea/fisiopatología , Índice Tobillo Braquial , Austria , Femenino , Estudios de Seguimiento , Alemania , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Resultado del Tratamiento , Grado de Desobstrucción VascularRESUMEN
The transjugular intrahepatic portosystemic stent-shunt (TIPS) has successfully been used in the management of refractory variceal bleeding and ascites in patients with portal hypertension. Major drawbacks are the induction of hepatic encephalopathy and shunt dysfunction. We present a 59-year-old woman with alcoholic liver cirrhosis who received a TIPS because of recurrent bleeding from esophageal varices. Stent occlusion occurred 4 mo after placement of the TIPS. Laboratory testing revealed resistance to activated protein C (APC). Combination therapy with low-dose enoxaparin and clopidogrel could not prevent her recurrent stent occlusion. Finally, therapy with high-dose enoxaparin was sufficient to prevent further shunt complications up to now (follow-up period of 1 year). In conclusion, early occlusion of a TIPS warrants testing for thrombophilia. If risk factors are confirmed, anticoagulation should be intensified. There are currently no evidence-based recommendations regarding the best available anticoagulant therapy and surveillance protocol for patients with TIPS.
Asunto(s)
Resistencia a la Proteína C Activada/metabolismo , Várices Esofágicas y Gástricas/cirugía , Hipertensión Portal/cirugía , Derivación Portosistémica Intrahepática Transyugular/efectos adversos , Stents , Trombosis/etiología , Anticoagulantes/metabolismo , Factor V/metabolismo , Femenino , Humanos , Persona de Mediana Edad , Complicaciones Posoperatorias , Proteína C/metabolismo , Recurrencia , Trombofilia/etiología , Trombofilia/metabolismo , Trombosis/metabolismoRESUMEN
PURPOSE: To evaluate biologic response to poly(hydroxymethyl-p-xylylene-co-p-xylylene) (PHPX)-coated stents in vitro and in vivo in sheep. MATERIALS AND METHODS: Physical stability, hemocompatibility, and cytotoxicity of the coating were first assessed in vitro. Thirty-six self-expanding nitinol (Memotherm), 24 stainless steel balloon-mounted (Palmaz), and 12 self-expanding nitinol (ZA) stents were coated with PHPX by using chemical vapor deposition polymerization. Seventy-two coated and 72 uncoated stents were placed into iliac arteries of 36 sheep. Sheep were classified into three groups of 12 animals each. In each group, six sheep were killed after 1 month; six, after 6 months. In each sheep, two uncoated stents were placed into one limb; two coated stents of the same type, into the opposite limb. In groups 1 and 2, Palmaz and Memotherm stents were used; in group 3, Memotherm and ZA stents were used. In groups 1 and 3, arteries were healthy. In group 2, arteries were pretreated with a Fogarty maneuver. Stent patency was measured with intravascular ultrasonography (US) and histologic analysis. Cellular response to coated and uncoated stents was assessed. Measurements were compared (Wilcoxon test). RESULTS: In vitro, PHPX coating was stable; hemocompatibility and cytotoxicity were similar to those of stainless steel. In vivo, patency of coated and uncoated Palmaz and ZA stents was not different (P >.05). Patency of coated and uncoated Memotherm stents did not differ in four of six follow-up subgroups, but it was significantly reduced in group 2 after 6 months (intravascular US, P =.03; histologic analysis, P =.01) and in group 3 after 1 month (histologic analysis, P =.01). Histologically, the cellular response to coated and uncoated stents was not different (P >.05). CONCLUSION: PHPX coating had good physical stability and biocompatibility in vitro and in vivo. Performance of coated and uncoated Palmaz and ZA stents was similar. Patency of Memotherm stents was similar in four of six follow-up subgroups. Materials effects did not result in severely enhanced neointimal hyperplasia.
Asunto(s)
Arteria Ilíaca/fisiología , Stents , Animales , Arteria Ilíaca/diagnóstico por imagen , Técnicas In Vitro , Masculino , Polímeros , Radiografía , OvinosRESUMEN
PURPOSE: To retrospectively evaluate results in 110 patients who had iliac arterial occlusive disease and were treated with stents before 1991. MATERIALS AND METHODS: From 1987 to 1990, 110 patients (mean age, 57 years) with iliac arterial occlusive disease (Fontaine stage IIa, seven patients; IIb, 95 patients; III, four patients; IV, four patients) underwent implantation of a self-expanding metal stent. Stenoses (n = 66) were treated after failed angioplasty, and occlusions (n = 60) were treated with primary stent placement. Follow-up included angiography and/or color duplex ultrasonography and clinical examination with ankle-brachial index measurement. Patients lost to follow-up were interviewed by using dedicated questionnaires administered by telephone and/or mail. If a patient was deceased, relatives and attending doctors were interviewed. RESULTS: The fate of 109 of the 110 patients was determined. Overall, 46 patients died: 18 within 5 years, 39 within 10 years, and seven after more than 10 years. The 5- and 10-year survival rates were 83% and 64%, respectively. Cardiovascular disease caused 23 deaths; malignant tumor caused 15. The cause of death remained unknown in five patients. Primary stent patency rates were 66% +/- 4.8 (standard error) after 5 years and 46% +/- 5.9 after 10 years; secondary patency rates were 79% +/- 4.2 after 5 years and 55% +/- 6.3 after 10 years (Kaplan-Meier test). Seventeen (16%) patients underwent surgical bypass of the aortoiliac arteries that involved the segment with the stent, 14 because of stent restenosis and three because of stenosis in other iliac arterial segments. CONCLUSION: The main cause of death in patients with intermittent claudication was cardiac disease. Long-term patency of iliac arterial stents was moderate.