Assessment of coronary artery stent restenosis by 64-slice multi-detector computed tomography.

AIMS: We investigated the feasibility of assessing coronary artery stent restenosis using a new generation 64-slice multi-detector computed tomography-scanner (MDCT) in comparison to conventional quantitative angiography. METHODS AND RESULTS: MDCT was performed in 64 consecutive patients (mean age 58+/-10 years) with previously implanted coronary artery stents (102 stented lesions: mean stent diameter 3.17+/-0.38 mm). Each stent was classified as 'evaluable' or 'unevaluable', and in evaluable stents, the presence of in-stent restenosis (diameter reduction >50%) was determined visually. Results were verified against invasive, quantitative coronary angiography. Fifty-nine stented lesions (58%) were classified as evaluable in MDCT. The mean diameter of evaluable stents was 3.28+/-0.40 mm, whereas the mean diameter of non-evaluable stents was 3.03+/-0.31 mm (P=0.0002). Overall, six of 12 in-stent restenoses were correctly detected by MDCT [50% sensitivity (confidence interval 22-77%)] and in 51 of 90 lesions, in-stent restenosis was correctly ruled out [57% specificity (46-67%)]. In evaluable stents, six of seven in-stent restenoses were correctly detected, and the absence of in-stent stenosis was correctly identified in 51 of 52 cases [sensitivity 86% (42-99%) and specificity 98% (88-100%)]. CONCLUSION: Stent type and diameter influence evaluability concerning in-stent restenosis by MDCT. The rate of assessable stents is low, but in evaluable stents, accuracy for detection of in-stent restenosis can be high.     

Clinical and angiographic predictors of recurrent restenosis after percutaneous transluminal rotational atherectomy for treatment of diffuse in-stent restenosis

Due to the widespread use of stents in complex coronary lesions, stent restenosis represents an increasing problem, for which optimal treatment is under debate. "Debulking" of in-stent neointimal tissue using percutaneous transluminal rotational atherectomy (PTRA) offers an alternative approach to tissue compression and extrusion achieved by balloon angioplasty. One hundred patients (70 men, aged 58 +/- 11 years) with a first in-stent restenosis underwent PTRA using an incremental burr size approach followed by adjunctive angioplasty. The average lesion length by quantitative angiography was 21 +/- 8 mm (range 5 to 68) including 22 patients with a length > or = 40 mm. Twenty-nine patients had complete stent occlusions with a lesion length of 44 +/- 23 mm. Baseline diameter stenosis measured 78 +/- 17%, was reduced to 32 +/- 9% after PTRA, and further reduced to 21 +/- 10% after adjunctive angioplasty. Primary PTRA was successful in 97 of 100 patients. Clinical success was 97%, whereas 2 patients developed non-Q-wave infarctions without clinical sequelae. Clinical follow-up was available for all patients at 5 +/- 4 months without any cardiac event. Angiography in 72 patients revealed restenosis in 49%, with necessary target lesion reintervention in 35%. The incidence of rerestenosis correlated with the length of the primarily stented segment and the length of a first in-stent restenosis. Thus, PTRA offers an alternative approach to treat diffuse in-stent restenosis. Neointimal debulking of stenosed stents can be achieved effectively and safely. PTRA resulted in an acceptable recurrent restenosis rate in short and modestly diffuse lesion, whereas the restenosis rate in very long lesions remains high despite debulking.     

Primary patency of long-segment self-expanding nitinol stents in the femoropopliteal arteries.

PURPOSE: To report a retrospective cohort study of nitinol stent implantation in patients at high risk for restenosis owing to long-segment (> or =10 cm) femoropopliteal disease. METHODS: Sixty-five consecutive patients with peripheral artery disease underwent long-segment (> or =10 cm) femoropopliteal stent implantation using self-expanding nitinol stents after initial failure of plain balloon angioplasty (i.e., residual stenosis >30% or a flow-limiting dissection). Patients were followed for first occurrence of in-stent restenosis, defined as a >50% lumen diameter reduction by color-coded duplex sonography, with angiographic confirmation. RESULTS: Cumulative median length of the stented segments was 16 cm (interquartile range [IQR] 12-25, absolute range 10-40) using up to 5 overlapping stents. During the median 8-month follow-up (IQR 6-11), no early thrombotic reocclusions occurred within 30 days, but 26 (40%) patients developed an in-stent restenosis. Cumulative freedom from restenosis at 6 and 12 months was 79% and 54% overall, respectively; at the same time periods, the rates were 84% and 71% in nondiabetic patients (n=41) versus 68% and 22% in diabetics (n=24) (adjusted hazard ratio 3.8, p=0.01). Cumulative stent length and number of implanted stents were not associated with restenosis. CONCLUSION: Midterm restenosis after long-segment femoropopliteal stenting using self-expanding nitinol stents remains a major problem, particularly in patients with diabetes mellitus. The midterm results in nondiabetics are encouraging.     

Drug-eluting and bare nitinol stents for the treatment of atherosclerotic lesions in the superficial femoral artery: long-term results from the SIROCCO trial.

PURPOSE: To review clinical outcomes of patients with chronic limb ischemia and TASC type C lesions treated with sirolimus-eluting versus bare SMART nitinol self-expanding stents. METHODS: Data were obtained from a randomized, multicenter, double-blinded study conducted in 2 phases. All 93 patients had chronic limb ischemia and superficial femoral artery (SFA) occlusions or stenoses (average lesion length 8.3 cm). In total, 47 patients (31 men; mean age 66.3+/-9.1 years, range 50-84) received the sirolimus-eluting SMART stent and 46 patients (36 men; mean age 65.9 +/-10.8 years, range 38-83) received a bare SMART nitinol stent. Both groups were followed for a mean 24 months. RESULTS: Both the sirolimus-eluting and the bare SMART stents were effective in revascularizing the diseased SFA and in sustaining freedom from restenosis. For both types of stents, improvements in ankle-brachial indices (ABI) and symptoms of claudication were maintained over 24 months (median 24-month ABI 0.96 for the sirolimus group versus 0.87 for the bare stent group, p>0.05). At 24 months, the restenosis rate in the sirolimus group was 22.9% versus 21.1% in the bare stent group (p>0.05). The cumulative in-stent restenosis rates according to duplex ultrasound were 4.7%, 9.0%, 15.6%, and 21.9%, respectively, at 6, 9, 18, and 24 months; the rates did not differ significantly between the treatment groups. The TLR rate for the sirolimus group was 6% and for the bare stent group 13%; the TVR rates were somewhat higher: 13% and 22%, respectively. Mortality rates did not differ significantly between the groups. CONCLUSION: These data demonstrate that the sirolimus-eluting and the bare SMART stent are effective, safe, and free from restenosis in a majority of patients for up to 24 months. Because the restenosis rate in the bare stent group is unexpectedly low, no significant difference could be found between the sirolimus-eluting and the bare SMART stents.     

Clinical and angiographic results of balloon-expandable intracoronary stents in right coronary artery stenoses

Balloon-expandable stents were placed successfully in 35 (95%) of 37 patients whose right coronary artery lesion was believed to have a poor short- or long-term prognosis with conventional balloon angioplasty because of prior restenosis or adverse lesion morphology. Quantitative angiography showed a reduction in stenosis diameter from 83 +/- 14% to 42 +/- 14% after conventional balloon dilation, with a further reduction to -3 +/- 12% after stent placement (p less than 0.001). There were no acute stent thromboses, but one patient (with two stents and unstented distal disease) developed subacute thrombosis on day 8 after self-discontinuation of warfarin and was treated with thrombolytic therapy and redilation. Follow-up angiography was performed at 4 to 6 months in 25 patients, demonstrating restenosis (83 +/- 13%) in 4 (57%) of 7 patients with multiple stents, but only 3 (17%) of 18 patients with a single stent (p less than 0.05). Six of the seven in-stent restenotic lesions were subtotal (80 +/- 12%) and were subjected to repeat conventional balloon angioplasty (postdilation stenosis 13 +/- 21%). The 18 patients without restenosis had a maximal in-stent diameter stenosis of 29 +/- 15%, corresponding to a maximal focal neointimal thickness of 0.68 +/- 0.26 mm within the stented segment. These preliminary results suggest that the Schatz-Palmaz stent may be a useful adjunctive device in the performance of coronary angioplasty.     

Angiographic pattern of restenosis following implantation of overlapping sirolimus-eluting (Cypher) stents

Sirolimus-eluting stents (Cypher) have been shown to reduce the frequency of neointimal hyperplasia and restenosis compared with bare metal stents. However, the clinical implication of overlapping stents with regard to the pattern of restenosis is unclear. All patients who underwent angiography at our institution from May 2003 to March 2005 who had previously received 2 overlapping Cypher stents in native coronary lesions and had binary restenosis were included in our study. Quantitative coronary analysis was performed to determine the degree and location of the restenotic lesion with respect to the overlapping stented segment. The primary end point was to determine how often restenotic lesions occurred at the overlapped segment versus the nonoverlapped stented segments. During the study, 11 patients fit the inclusion criteria for our study; 91% were men and 55% had diabetes mellitus. The mean total stent length was 33.7 +/- 8.2 mm. The mean length of the overlapped segment was 5.9 +/- 3.8 mm, equating to 19 +/- 16% of the total stented area. The average time to follow-up angiography was 277 +/- 126 days. All 11 lesions exhibited type 1 (focal) restenosis. Of these 11 lesions, 10 had focal restenosis at the overlapped segment (p = 0.01, binomial test). The single case involving in-stent restenosis in the nonoverlapped segment occurred at the proximal stent edge. In conclusion, the pattern of restenosis observed in our study suggests a higher relative incidence of binary restenosis in the overlapped stented segment in patients who receive 2 overlapping Cypher stents.     

Effects of stent length and lesion length on coronary restenosis

The choice of drug-eluting versus bare metal stents is based on costs and expectations of restenosis and thrombosis risk. Approaches to stent placement vary from covering just the zone of maximal obstruction to stenting well beyond the lesion boundaries (normal-to-normal vessel). The independent effects of stented lesion length, nonstented lesion length, and excess stent length, on coronary restenosis have not been evaluated for bare metal or drug-eluting stents. We analyzed the angiographic follow-up cohort (1,181 patients) from 6 recent bare metal stent trials of de novo lesions in native coronary arteries. Stent length exceeded lesion length in 87% of lesions (mean lesion length 12.4 +/- 6.3 mm, mean stent length 20.0 +/- 7.9 mm, mean difference 7.6 +/- 7.9 mm). At 6- to 9-month follow-up, the mean percent diameter stenosis was 39.1 +/- 20.1%. In an adjusted multivariable model of percent diameter stenosis, each 10 mm of stented lesion length was associated with an absolute increase in percent diameter stenosis of 7.7% (p <0.0001), whereas each 10 mm of excess stent length independently increased percent diameter stenosis by 4.0% (p <0.0001) and increased target lesion revascularization at 9 months (odds ratio 1.12, 95% confidence interval 1.02 to 1.24). Significant nonstented lesion length was uncommon (12.5% of cases). In summary, stent length exceeded lesion length in most stented lesions, and the amount of excess stent length increased the risk of restenosis independent of the stented lesion length. This analysis supports a conservative approach of matching stent length to lesion length to reduce the risk of restenosis with bare metal stents.     

Membrane-covered stents: a new treatment strategy for saphenous vein graft lesions.

The restenosis rate after stenting of lesions in aortocoronary venous bypass grafts still has to be considered unsatisfactorily high. We investigated a new stent design characterized by an expandable polytetrafluorethylene (PTFE) membrane in between two layers of struts. Five consecutive male patients (age 70 +/- 6 years) were followed prospectively who presented with at least two de novo lesions in different grafts 13 +/- 3 years after bypass surgery. A total of 11 lesions were treated located in grafts anastomosed to the circumflex (n = 3), to the LAD (n = 7), and to the right coronary artery (n = 1). Within the same procedure, every patient received membrane-covered stents (n = 6) and conventional stents (n = 5) in either of their lesions. All patients underwent successful interventions. The minimal luminal diameter increased from 1.0 +/- 0.5 to 2.9 +/- 0.6 mm in lesions treated by the membrane-covered stents and from 0.8 +/- 0.4 to 2.4 +/- 0.7 mm in the lesions treated by conventional stents. During follow-up, four out of five patients required angioplasty for in-stent restenosis of lesions covered by a conventional stent, whereas no patient underwent revascularization for a lesion treated by a membrane-covered device. The mean minimal luminal diameter of lesions covered by a conventional stent decreased by 42% to 1.4 +/- 0.6 mm; the mean minimal luminal diameter of the lesions treated by a stent graft declined by 9% to 2.8 +/- 0.6 mm (P < 0.05). This series of intraindividual comparisons suggests that membrane-covered stents may have the power to reduce in-stent restenosis in obstructed aortocoronary venous bypass grafts.     

Early and late outcome of stenting in a consecutive series of patients with coronary lesions in vessels less than 2.8 mm in diameter

In an attempt to determine the early and late outcomes of small vessel stenting, we retrospectively evaluated our database on 51 consecutive patients (41 males, mean age, 57.1 +/- 10.1 years) who underwent stenting of at least one significant lesion in a coronary artery with a reference vessel diameter (RVD) <2.8 mm between March 1999 and March 2001. Sixty balloon expandable tubular stents were implanted in 57 lesions (29 Type B2/C, mean RVD: 2.54 +/- 0.16 mm) without intravascular ultrasound guidance under a heparin-aspirin-ticlopidine regimen. The mean diameter stenosis (DS) decreased from 75.8 +/- 13.6% to 4.2 +/- 1.9% (P<0.0001) with stenting at a mean deployment pressure of 13.6 +/- 1.7 atm and a final balloon to RVD ratio (FB/RVD) of 1.08 +/- 0.03. All stents were deployed successfully. Acute stent thrombosis occurred in 3 patients (6%), one died, and 2 developed non-Q-wave myocardial infarction (procedural success 94%). Clinical follow-up, available in 48 patients, revealed a 29% target lesion revascularization rate, a 2% myocardial infarction rate, and a 71% event-free survival at a mean of 11.6 months. Angiographic follow-up, available in 40 patients, showed a DS of 48.8 +/- 31.3% and a binary restenosis rate of 50% at a mean of 7.7 months. The FB/RVD ratio was significantly lower in the group with restenosis than in the group without (1.06 +/- 0.02 vs 1.1 +/- 0.05, P = 0.04). Subgroup analysis yielded a significantly greater rate of restenosis in diabetics with complex (Type B2/C) lesion morphology compared to nondiabetics with simple (Type A/B1) lesions (75% vs 21%, P < 0.05). In conclusion, stenting in vessels <2.8 mm was found to be associated with a high rate of acute stent thrombosis and in-stent restenosis. Further analysis detected a subgroup of patients without diabetes or complex lesions who could be stented with an acceptable in-stent restenosis rate.     

Standardized angiographically guided over-dilatation of stents using high pressure technique optimize results without increasing risks

BACKGROUND: Routine angio-guided stent deployment results in a relatively high restenosis rate, which is mostly due to stent sub-expansion. Several different intravascular ultrasound (IVUS) criteria for optimal stent deployment have been proposed. A minimal in-stent restenosis and a minimal in-stent lumen area of > or = 9 mm2 have been associated with low rates of restenosis and target lesion revascularization (TLR) at 6 months. The role of high-pressure stent deployment and/or upsizing the post-dilatation balloon has not yet been clarified. The aim of this study was to evaluate the possibility of achieving accepted IVUS criteria safely without IVUS guidance with the combination of high-pressure deployment and post-dilatation with a 0.25 mm oversized balloon. METHODS: Thirty-four stents (26 NIR, 3 AVE GFX, 3 ACS GFX, 1 Bard, 1 Jostent) were implanted in 30 patients until optimal angiographical results were obtained (< 10% residual stenosis visually). Forty percent of the patients had unstable angina pectoris, forty-four percent had complex lesions (B2 and C) and 29% were occlusions. Mean inflation pressure was 12.6 +/- 1.6 atm, mean stent diameter was 3.2+/- 0.4 mm and mean stent length was 15.1+/- 5.4 mm. Post-dilatation was performed with the same stent using a short (compared to the angiographic reference segment), 0.25 mm oversized Scimed Maxxum Energy 3.5 +/- 0.4 mm balloon using high pressure (16.1 +/- 1.7 atm) followed by an off-line IVUS examination of the stents. There was clinical follow-up for 1 year. Results in patients with single-vessel disease were compared with those of non-randomized controls, who were stented with high pressure but without over-dilatation. RESULTS: No stent achieved the nominal diameter, in spite of over-dilatation. Mean minimal stent diameter (MLD) according to IVUS was 2.9 +/- 0.4 mm (92% of the angiographic reference diameter). Mean minimal lumen area (MLA) was 7.7 +/- 2.2 mm2. An in-stent MLA > or = 90% of the distal reference segment (AVID criteria) and an MLA > or = 100% or > or = 90% of the smallest/average reference segment (MUSIC criteria) was found in 67% and 57%, respectively. MLA > or = 9 mm2 was achieved in 38%. All stents had good apposition and obtained a symmetry index > or = 0.7 mm. No acute perforations, dissections or other serious complications occurred during the over-dilatation. At 1 year, five patients had re-angina leading to a new coronary angiography; only 1 patient had a significant in-stent restenosis requiring re-PTCA. Compared to non-overdilated historical controls, the standardized over-dilatation seemed to give a larger MLD (3.0 +/- 0.4 mm vs. 2.7 +/- 0.4 mm; p = 0.03), more patients who fulfilled AVID criteria (70% vs. 32%; p = 0.048) and more stents with MLA > or = 9 mm2 (46% vs. 11%; p = 0.02). CONCLUSION: A standardized 0.25 mm over-dilatation of stents never achieved nominal stent size, but did improve lumen gain and was associated with low target vessel revascularization without adding complications to the routine stenting procedure.     

Prevalence and clinical impact of stent fractures after femoropopliteal stenting

OBJECTIVES: The aim of this study was to investigate the occurrence and the clinical impact of stent fractures after femoropopliteal stenting. BACKGROUND: The development of femoral stent fractures has recently been described; however, there are no data about the frequency and the clinical relevance. METHODS: A systematic X-ray screening for stent fractures was performed in 93 patients. In total, 121 legs treated by implantation of self-expanding nitinol stents were investigated after a mean follow-up time of 10.7 months. The mean length of the stented segment was 15.7 cm. RESULTS: Overall, stent fractures were detected in 45 of 121 treated legs (37.2%). In a stent-based analysis, 64 of 261 stents (24.5%) showed fractures, which were classified as minor (single strut fracture) in 31 cases (48.4%), moderate (fracture of >1 strut) in 17 cases (26.6%), and severe (complete separation of stent segments) in 16 cases (25.0%). Fracture rates were 13.2% for stented length < or =8 cm, 42.4% for stented length >8 to 16 cm, and 52.0% for stented length >16 cm. In 21 cases (32.8%) there was a restenosis of >50% diameter reduction at the site of stent fracture. In 22 cases (34.4%) with stent fracture there was a total stent reocclusion. According to Kaplan-Meier estimates, the primary patency rate at 12 months was significantly lower for patients with stent fractures (41.1% vs. 84.3%, p < 0.0001). CONCLUSIONS: There is a considerable risk of stent fractures after long segment femoral artery stenting, which is associated with a higher in-stent restenosis and reocclusion rate.     

Intracoronary radiotherapy with a (188)rhenium liquid-filled PTCA balloon system in in-stent restenosis: acute and long-term angiographic results, as well as 1-year clinical follow-up

BACKGROUND: Intracoronary radiotherapy with beta- and gamma-emitters has been shown to reduce the risk of restenosis after balloon angioplasty and after coronary stenting. The present study addresses the question whether intracoronary radiotherapy using the (188)rhenium liquid-filled PTCA balloon system is feasible, safe and effective in cases of in-stent restenosis. Acute and long-term angiographic results as well as clinical events within 1 year after the procedure were evaluated. METHODS AND RESULTS: From September 1999 to April 2000, 41 patients (mean age 60+/-10 years, 33 male, 8 female) with symptomatic in-stent restenosis underwent repeat PTCA and immediate intracoronary brachytherapy. After successful repeat PTCA (residual stenosis less than 30% in diameter), a second standard PTCA catheter was inflated with liquid (188)rhenium in the redilated in-stent restenosis for 315-880, mean 540+/-155 s with low pressure (3 atm) in order to reach 30 Gy at 0.5 mm depth of the vessel wall. In all patients with successful reintervention, intracoronary radiotherapy was unproblematically performed; in 16 patients, 21 new stents were implanted during the procedure-either immediately before or after radiation therapy. During follow-up, four episodes of stent thrombosis with subsequent myocardial infarction occurred in three patients (8 days, 37 days, 5 months and 6 months after the procedure, respectively). This complication was seen exclusively in patients with newly implanted stents. One patient of the stent group died suddenly 46 days after the procedure. All 40 surviving patients underwent repeat angiography in cases of repeat angina or routinely 6 months after brachytherapy, respectively. In the redilated target vessels without new stenting, restenosis (stenosis >50% in diameter) or reocclusion was observed in only 5 of 25 (=20%) cases, but in the restented target lesions, in 10 of 15 (=67%). Event-free survival (death, myocardial infarction, TVR) at 1 year after repeat dilatation and subsequent brachytherapy was 80% for patients not newly stented, but only 44% for patients with new stents. CONCLUSIONS: Intracoronary radiation therapy with the liquid-filled beta-emitting (188)rhenium balloon is a safe and effective therapy in cases of in-stent restenosis. The positive effect of irradiation, however, is abolished if a new stent is needed. In the not newly stented patients, 1-year follow-up is encouraging.     

Sirolimus-eluting stent in chronic total occlusion: the SICTO study

Coronary stenting can significantly reduce the restenosis and reocclusion rates after successful balloon angioplasty for chronic total occlusions (CTO). Nevertheless, recanalization of CTO remains among the worst predictors for in-stent restenosis and reocclusion. This multicenter, nonrandomized study assessed the safety and effectiveness of the CYPHER sirolimus-eluting stent in reducing angiographic in-stent late loss in totally occluded native coronary arteries. A total of 25 eligible patients were treated with the CYPHER sirolimus-eluting stent. Baseline clinical and angiographic data were collected and 6-month follow-up angiography and intravascular ultrasound (IVUS) were performed. Clinical follow-up was required at 30 days, 6, 12, 18, and 24 months. Study stent implantation was successful in all patients, with a mean stent length of 28.4 +/- 11 mm. Six-month angiographic outcomes showed that mean lumen diameter stenosis did not change (2.22 +/- 0.56 mm postprocedure; 2.26 +/- 0.60 mm at 6 months follow-up; P = NS). Similarly, mean percent diameter stenosis did not change significantly (15.7 +/- 8.6% postprocedure, 19.3 +/- 11% at follow-up; P = NS). The absolute late lumen loss was -0.03 +/- 0.28 mm with a 6-month in-stent restenosis rate of 0%. IVUS follow-up revealed in-stent obstruction volume of only 4.9 +/- 6.8%. Long-term clinical follow-up showed target lesion revascularization at 12 months was only 4%, with target vessel revascularization of only 12%. The CYPHER sirolimus-eluting stent was safe and effective in the treatment of CTO compared to historical data with bare metal stents.     

Angiographic and clinical outcome following sirolimus-eluting stent (Cypher) implantation. A single center experience

OBJECTIVES: To investigate the late outcomes of sirolimus-eluting stent implantation in patients with coronary artery disease. BACKGROUND: Drug-eluting stents reduce intimal hyperplasia, which is the main cause of in-stent restenosis. Sirolimus-eluting stents significantly reduce clinical and angiographic restenosis and improve event-free survival. METHODS: The study population consisted of 207 patients (273 stents) who had undergone coronary Cypher stent implantation. Patients were eligible for enrollment if there was symptomatic coronary artery disease or positive exercise testing, and angiographic evidence of single or multivessel disease with a target lesion stenosis of > or = 70% in a > or = 2.25 mm vessel. Follow-up coronary angiography was performed 18 months after stent deployment. Patients were followed-up for a mean of 24.7 +/- 7.4 months. RESULTS: All patients survived after stent implantation, but 5 (2.4%) patients experienced acute ST elevation myocardial infarction and 4 (1.9%) patients developed non-Q wave myocardial infarction following angioplasty. Recurrent angina pectoris was observed in 16 (7.7%) patients (11 stable angina pectoris and 5 unstable angina pectoris). Angiographic evidence of restenosis was observed in these 20 (9.66%) patients. The 5 other patients had noncritical angiographic restenosis. Eleven (5.3%) patients underwent angioplasty because of restenosis, and coronary artery bypass grafting was conducted in the other 9 (4.3%) patients. CONCLUSION: The results of the present study indicate that Cypher stents could be implanted with a very high success rate and have encouraging long-term angiographic and clinical results.     

Randomized, double-blind, multicenter study of the polymer-based 17-beta estradiol-eluting stent for treatment of native coronary artery lesions: six-month results of the ETHOS I trial.

OBJECTIVES: The ETHOS I trial was the first in-human experience evaluating the safety and efficacy of two different release formulations of the 17-beta estradiol-eluting R-Stent versus uncoated control stents for the treatment of patients with single de novo native coronary lesions. BACKGROUND: Estrogens were reported to inhibit neointimal proliferation and to accelerate endothelial regeneration after coronary angioplasty and thus could be an ideal compound to deliver on a stent for the purpose of reducing in-stent restenosis. METHODS: Ninety-five patients were randomized to receive a slow-release (n = 32) or the moderate release (n = 31) formulations or the bare metal stent (n = 32). The primary end point was the 6-month percent in-stent volume obstruction by intravascular ultrasound (IVUS). RESULTS: Diabetes was present in 29.5% of patients; the mean reference vessel diameter was 2.90 mm; and the mean lesion length was 13.5 mm. Primary endpoint, 6-month percent in-stent volume obstruction by IVUS, did not differ significantly between the 3 groups (31% +/- 14%, 33% +/- 11%, and 31% +/- 14%, P = 0.83). Secondary endpoints also did not differ significantly between the groups including 6-month rates of in-lesion binary angiographic restenosis (13.3%, 14.3%, and 12.5%, P = 0.98), in-stent late loss (0.82 +/- 0.49 mm, 0.86 +/- 0.53 mm, and 0.84 +/- 0.46 mm, P = 0.97), target lesion revascularization (12.5%, 6.9%, and 6.5%, P = 0.64), and major adverse cardiac events (18.8%, 10.3%, and 6.5%, P = 0.31). CONCLUSIONS: In this first-in-man randomized trial, the 17-beta estradiol-eluting R-Stent, in either slow- or moderate-release formulations, was well-tolerated, but showed no benefit for treatment of coronary lesions when compared to controls.     

Intracoronary Stenting for Restenosis: Long-Term Follow-up: A Single Center Experience

One-hundred thirteen stents (78 Wallstents, 29 Palmaz-Schatz and 6 Wiktor) were implanted in 106 patients aged 63 +/- 5 years to treat a restenosis following previous angioplasty in a native coronary artery (86 cases) and in a venous graft (20 cases). Implantation was technically possible in all cases. The native vessels had a mean reference diameter of 3.3 +/- 0.3 mm and their mean minimal lumen diameter increased from 1.2 +/- 0.3 mm before angioplasty to 2.8 +/- 0.8 after stent implantation. The venous grafts mean reference diameter was 4.4 +/- 0.7 mm and their mean minimal lumen diameter increased from 1.3 +/- 0.4 mm before angioplasty to 4.0 +/- 0.7 mm after implantation. Percentage stenosis in the native arteries and in the venous grafts were respectively 78 +/- 13% and 69 +/- 14% before angioplasty and 24 +/- 8% and 22 +/- 8% after stent implantation. Complications at 6 months, presented as a ranking scale with 100% follow-up rate were, overall, of 20% clinical events (4% deaths, 6% myocardial infractions, 2% coronary artery bypass grafting and 8% re-angioplasty). Angiographic complications were of 8% subacute thrombosis and 19% restenosis and chronic occlusions. Long-term, at 65 +/- 9 months, clinical (86% follow-up) and angiographic (74% follow-up) showed that only a further 9% clinical events and 14% restenosis (12% of them between 6 and 12 months) occurred after 6 months. At an estimated follow-up time of 104 months, 70% patients remain event-free and the survival rate is 95%. In conclusion, stent implantation in the treatment of restenosis following conventional balloon angioplasty is a valid strategy with good long-term results.     

两种药物洗脱支架在冠状动脉复杂弥漫病变中的疗效比较

目的比较雷帕霉素洗脱支架(SES)和紫杉醇洗脱支架(PES)对长度≥25mm复杂病变的疗效。方法入选138例患者(男124例,女14例)冠状动脉(冠脉)病变长度≥25mm,接受SES和PES介入治疗,并且在支架术后6个月左右接受冠脉造影随访。结果共147处病变在6个月后随访。其中2型糖尿病患者43例(31·2%),C型病变129处(87·8%)。SES组的支架内再狭窄率(5·9%,17·7%,P=0·023)、支架段再狭窄率(9·4%,21·0%,P=0·048)和支架段晚期腔径丢失[(0·16±0·52)mm比(0·45±0·65)mm,P=0·003)]、支架内晚期腔径丢失[(0·26±0·46)mm比(0·60±0·66)mm,P=0·001)]明显低于PES组。两组之间在随访期间靶病变血管重建率(7·1%比12·9%,P=0·223)差异无统计学意义。结论对于复杂弥漫病变SES在再狭窄率和晚期腔径丢失要优于PES,对于远期预后的影响还需要进一步的观察。SES更适合用于复杂小血管病变。     

Multislice computed tomographic angiography versus digital subtraction angiography in the follow-up of nitinol stents in the superficial femoral artery.

PURPOSE: To compare quantitative and qualitative parameters obtained from digital subtraction angiography (DSA) with multislice computed tomographic angiography (MSCTA) in the follow-up of superficial femoral artery (SFA) stents. METHODS: Thirteen patients who had SMART stents implanted in the SFA were examined systematically with DSA and MSCTA (16-row scanner) at 6 months. Quantitative analysis and morphological assessment were performed on DSA images by an independent core laboratory, while the MSCTA images were analyzed by 2 radiologists in consensus. DSA measurements included stent length, minimal lumen diameter and reference diameter at mid stent and 5 mm either side of the stent, and percentage of stenosis. For MSCTA images, lumen area and the minimum, maximum, and mean diameters were also recorded. The images were analyzed qualitatively for diameter stenosis (<50%, 50% to 70%, 71% to 99%, and occlusion), bends, fractures, and calcifications. RESULTS: There were no statistical differences between lengths of stented segments, diameter measurements, or percentages of stenosis from DSA and MSCTA images. The Bland-Altman method showed good agreement between the 2 methods of measurement. MSCTA detected in-stent proliferation with a diameter stenosis <50% in all 13 cases diagnosed on DSA (there was no stenosis >50%). There were no bends or stent fractures on either set of images. The agreement between DSA and MSCTA for the presence and grading of calcifications was moderate (kappa=0.5). CONCLUSION: MSCTA provided quantitative and qualitative data comparable with DSA in the analysis of SFA nitinol stents.     

Long-term (> 3 years) clinical and angiographic outcomes of coronary multilink stent implantations: a single center experience

The ACS Multilink (ML) stent is a novel second-generation stent. The largest amount of information available on the long-term outcome of coronary stenting is based on the use of Palmaz-Schatz stents. Fewer data exist on long-term follow-up results of ML coronary stents implantations. The authors present the long-term (> 3 years) clinical and angiographic follow-up results of the ACS Multilink coronary stents implanted in their institution. From May 1996 to December 1997, 125 patients underwent 133 coronary ML stent implantations. Stented vessels were as follows: 49% left anterior descending artery, 31% right coronary artery, and 20% left circumflex coronary artery. Indications for stent implantations were elective in 64%, because of suboptimal result from percutaneous transluminal coronary angioplasty (PTCA) in 26%, and bailout from PTCA in 10% of patients. The mean reference diameter of stented vessels was 3.2 +/- 0.2 mm. The mean percentage stenosis was 80 +/- 11% and 3 +/- 5% before and after stent implantation, respectively. Long-term clinical follow-up was completed in 75% (80 men, mean age 53 +/- 10 years) of the patients (either by interview or phone), and angiographic follow-up (37 +/- 12 months) was completed in 58% of the patients. There were no baseline clinical or angiographic differences between those angiographically followed up and the remaining patients. Angiographic restenosis (> 50% diameter stenosis) was detected in 22% of stents. Target lesion revascularization was 12%, nontarget lesion revascularization was 14% in angiographically followed up patients. During the follow-up period death and new myocardial infarction occurred in 12% and 6% of patients, respectively, and survival rate was 88%. This study provides long-term follow-up results of intracoronary Multilink stent implantations for native coronary artery lesions. These data show that clinical and angiographic benefits of ML stents are comparable to those of the first-generation stents, especially to the Palmaz-Schatz stents, of which results have been reported previously. A considerable rate of nontarget lesion revascularization occurs during the follow-up period.     

Palmaz-Schatz Coronary Stent Implantation Without Intravascular Ultrasound and Without Subsequent Anticoagulation: Clinical Outcome

OBJECTIVES: To determine the safety and efficacy of antiplatelet therapy alone in a selected group of patients following coronary stenting. BACKGROUND: Coronary stent implantation is an effective treatment for abrupt closure, and can also reduce the restenosis rate following percutaneous transluminal coronary angioplasty. However, anticoagulation therapy following stent implantation is associated with a significant incidence of vascular complications and subacute stent thrombosis. METHODS: Between February and November 1994 we implanted 62 Palmaz-Schatz stents in 50 patients with an optimal angiographic result following stent deployment. In these patients, intravascular ultrasound was not used, and a regimen of aspirin 100 mg daily indefinitely and ticlopidine 250 mg twice daily for 3 months was started without anticoagulation. RESULTS: Of these 50 patients (10 females : 40 males, mean age 63 +/- 12 years, LVEF 64 +/- 10%), 39 (78%) were stented for a suboptimal angiographic result post angioplasty, 2 (4%) received stents as a bailout procedure, and 9 (18%) were stented electively. Average hospital stay following stent implantation was 3.7 +/- 3.0 days. After a mean follow-up period of 140 +/- 70 days, there were no instances of stent occlusion, death, stroke, need for coronary bypass surgery, Q-wave myocardial infarction or femoral artery pseudoaneurysm. There was 1 case (2%) of significant puncture site hemorrhage. CONCLUSIONS: Immediate angiographic appearance after stent implantation can be used to define patients at low risk of stent thrombosis who do not require anticoagulation and can safely be discharged early from the hospital.