Randomized comparison of success and adverse event rates and cost effectiveness of one long versus two short stents for treatment of long coronary narrowings

Long stents of high flexibility and low profile have become widely available. Treatment of long coronary lesions by 1 long stent may require less interventional efforts and reduce the rate of restenosis due to a lack of overlapping stent segments. This study sought to evaluate the use of 1 long stent compared with 2 short stents for treatment of long coronary lesions. One-hundred twenty-four patients with a coronary lesion 20 to 40 mm in length, in a vessel 2.5 to 4.0 mm in diameter, were randomly assigned to treatment with 1 long stent (GFX II stents or S670 of 24, 30, or 40 mm lengths; n = 62) or 2 stents (GFX II or S670 stents, n = 62) of equal length. Procedural success, interventional costs, as well as long-term clinical and angiographic outcomes were evaluated. Lesion characteristics were similar for the 2 treatment groups. Stent placement was possible as assigned by randomization in 61 of 62 cases (98%) in the 1-long-stent group and 100% of cases in the 2-short-stents group. There was crossover to successful short-stent placement in 1 case. The in-hospital success rate was 97% for the 1-long-stent group and 98% for the 2-short-stents group. Acute angiographic results were similar for both groups after intervention. The angiographic restenosis rate at 6 months was 38.5% in the 1-long-stent group and 37.5% in the 2-short-stents group (p = 0.919). Intervention time was less, and the need for a contrast agent had a tendency to be lower in the long-stent group. Procedural costs were significantly less in the long-stent group. In conclusion, 1 long stent can be used with identical procedural success and adverse event rates as 2 short stents in long, atherosclerotic coronary lesions. The restenosis rate is not reduced by the use of 1 long stent compared with 2 stents. However, long stent placement is highly cost effective.     

Long-term clinical outcomes after coronary angioplasty using long stents in small coronary vessels.

The role of coronary stenting in challenging situations, such as small vessels and long lesions, remains controversial. The aim of this study was to examine the procedural, in-hospital, and long-term clinical outcomes of patients undergoing angioplasty with long stents in small coronary vessels. We evaluated the procedural success rate and clinical outcomes in 252 consecutive subjects treated by means of the implantation of a single coronary stent in vessels with a mean reference diameter of < 2.5 mm; 128 patients received a short stent (< or = 16 mm) and 124 a long stent (> or = 18 mm). Lesion morphology was more complex in patients treated with long stents (P < 0.05). The mean stent length was 14 +/- 2 mm in the short-stent group and 25 +/- 3 mm in the long-stent group (P < 0.001). The overall procedural success rate (98.4% vs. 97.6%; P = NS) and the rate of major in-hospital adverse events (death, acute myocardial infarction, or target vessel revascularization; 1.6% vs. 2.4%; P = NS) was similar in the two groups. After 11.7 +/- 7 months of follow-up, there was no difference in the incidence of mortality and myocardial infarction (5% vs. 6.6%; P = NS), but revascularization tended to occur more frequently in the patients treated with long stents (21.7% vs. 13.9%; P = NS). In conclusion, the procedural success rate of single short or long stents in small coronary vessels was similar. Although the incidence of target vessel revascularization tended to be higher in the patients treated with longer stents, 2-year event-free survival was equivalent in the two groups (65% vs. 70%; P = NS).     

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.     

Outcomes of paclitaxel-eluting stent implantation in patients with stenosis of the left anterior descending coronary artery

OBJECTIVES: We sought to examine the efficacy of paclitaxel-eluting stent implantation in the left anterior descending coronary artery (LAD). BACKGROUND: Restenosis and recurrent cardiac events after percutaneous intervention are more common for lesions in the LAD than other native coronary arteries, and often necessitate bypass surgery. Drug-eluting stents may improve the long-term prognosis of this high-risk group. METHODS: In the TAXUS-IV trial, 1,314 patients with single de novo coronary lesions were assigned to implantation of the slow-release, polymer-based, paclitaxel-eluting TAXUS stent or an identical bare-metal stent; 536 (41%) randomized patients had LAD lesions. RESULTS: Baseline characteristics of patients with LAD lesions were well-matched between the randomized groups. Late lumen loss at nine months after paclitaxel-eluting and control stent implantation were 0.28 +/- 0.51 mm and 0.54 +/- 0.57 mm, respectively (p = 0.0004), and binary restenosis rates were 11.3% and 26.9%, respectively (p = 0.004). At one year, major adverse cardiac events (MACE) occurred in 13.5% of TAXUS-treated patients versus 21.2% treated with the control stent (p = 0.01). The need for bypass surgery at one year was reduced among patients randomized to the TAXUS stent (2.6% vs. 6.3%, p = 0.02). In the proximal LAD subgroup (n = 126), the one-year target vessel revascularization rate was 7.9% with the TAXUS stent and 18.6% with the bare-metal stent (p = 0.009). CONCLUSIONS: Compared to bare-metal stents, implantation of polymer-based, paclitaxel-eluting stents in LAD lesions is safe, and reduces angiographic restenosis and MACE one year. Notably, the need for bypass graft surgery due to restenosis is reduced after TAXUS stent implantation in LAD lesions.     

Intravascular ultrasound parameters associated with stent thrombosis after drug-eluting stent deployment

Drug-eluting stent (DES) thrombosis (ST) can be devastating. The study aim was to evaluate intravascular ultrasound (IVUS) predictors for DES thrombosis by comparing IVUS studies after implantation in 13 patients with 14 DES thrombosis lesions with a group of controls (30 lesions in 27 patients) matched for history of chronic renal failure and type of DES. Five patients (38%) discontinued dual antiplatelet therapy at the time of ST. There were 3 in-stent restenosis lesions (21%) treated using DESs in the ST group compared with 0 in the control group (p <0.05). Compared with the control group, IVUS studies in the ST group showed a smaller minimum stent area (4.6 +/- 1.1 vs 5.6 +/- 1.7 mm(2), p = 0.0489). In the ST group, 11 of 14 stents had a minimum stent area < or =5.0 mm(2) compared with 12 of 30 in the control group (p = 0.0392). Minimum stent area in patients who stopped clopidogrel therapy and developed ST (5.30 +/- 1.15 mm(2)) tended to be larger compared with that in patients who developed ST while using clopidogrel (4.24 +/- 0.96 mm(2), p = 0.091). Within the 5-mm-long proximal and distal reference segments analyzed, the ST group had larger proximal reference maximum plaque burdens and smaller minimum lumen areas, along with a tendency toward similar findings in the distal reference segments. In conclusion, IVUS findings at the time of DES implantation in patients who subsequently developed ST showed a smaller minimum stent area (especially in patients who developed ST while using clopidogrel) and more residual disease at the stent edges.     

Clinical and angiographical follow-up after implantation of a 6--12 microCi radioactive stent in patients with coronary artery disease.

AIMS: This study is the contribution by the Thoraxcenter, Rotterdam, to the European(32)P Dose Response Trial, a non-randomized multicentre trial to evaluate the safety and efficacy of the radioactive Isostent in patients with single coronary artery disease. METHODS AND RESULTS: The radioactivity of the stent at implantation was 6--12 microCi. All patients received aspirin indefinitely and either ticlopidine or clopidogrel for 3 months. Quantitative coronary angiography measurements of both the stent area and the target lesion (stent area and up to 5 mm proximal and distal to the stent edges) were performed pre- and post-procedure and at the 5-month follow-up. Forty-two radioactive stents were implanted in 40 patients. Treated vessels were the left anterior descending coronary artery (n=20), right coronary artery (n=10) or left circumflex artery (n=10). Eight patients received additional non-radioactive stents. Lesion length measured 10+/-3 mm with a reference diameter of 3.07+/-0.69 mm. Minimal lumen diameter increased from 0.98+/-0.53 mm pre-procedure to 2.29+/-0.52 mm (target lesion) and 2.57+/-0.44 mm (stent area) post-procedure. There was one procedural non-Q wave myocardial infarction, due to transient thrombotic closure. Thirty-six patients returned for angiographical follow-up. Two patients had a total occlusion proximal to the radioactive stent. Of the patent vessels, none had in-stent restenosis. Edge restenosis was observed in 44%, occurring predominantly at the proximal edge. Target lesion revascularization was performed in 10 patients and target vessel revascularization in one patient. No additional clinical end-points occurred during follow-up. The minimal lumen diameter at follow-up averaged 1.66+/-0.71 mm (target lesion) and 2.12+/-0.72 (stent area); therefore late loss was 0.63+/-0.69 (target lesion) and 0.46+/-0.76 (stent area), resulting in a late loss index of 0.65+/-1.15 (target lesion) and 0.30+/-0.53 (stent area). CONCLUSION: These results indicate that the use of radioactive stents is safe and feasible, however, the high incidence of edge restenosis makes this technique currently clinically non-applicable.     

Expansion of the Multilink-Tristar stent after direct implantation and predilatation: comparison of clinical,angiography and intravascular ultrasound parameters

Coronary stenting has become the primary therapeutic option for many coronary lesions. As opposed to conventional stenting the advantages of direct stenting are a reduction of procedural time, radiation exposure and costs. However, data about the incidence of in-stent restenosis are so far not available. It was the aim of this prospective study to compare the expansion of the Multilink stent after direct stenting and predilatation by quantitative coronary angiography (QCA) and intravascular ultrasound (IVUS). Between January 2000 and June 2001, 82 patients were assigned to direct stenting (46 lesions) or predilatation (40 lesions) in lesions of coronary arteries > 3 mm. The procedural success rate was 92% in patients undergoing direct stenting. The baseline clinical characteristics were similar in both groups. The comparison of the angiographic data shows that direct stenting was performed in lesions with a lower degree of stenosis (71 +/- 12% vs 79 +/- 11%, p = 0.01) and that significantly shorter stents were used (14.4 +/- 3.0 vs 17.8 +/- 4.1 mm, p = 0.0007). The mean stenosis length was not significantly different in either group (10.5 +/- 3.4 vs 11.7 +/- 4.3 mm, n.s.). The QCA data after stent implantation show no differences of either implantation technique. Stent expansion was assessed by IVUS estimation of the proximal, distal and minimal in stent area. The minimal in-stent area (9.53 +/- 3.23, mm2 vs 8.65 +/- 1.96 mm2, n.s.) and the stent symmetry index (0.88 vs 0.88 n.s.) were not different in either patient group. These results indicate that in this subset of selected coronary lesions > 3 mm, elective stent implantation with and without predilatation effectively can achieve comparable stent expansion as assessed by QCA and IVUS. In comparison to conventional stent implantation stents, which were implanted without predilatation, were significantly shorter to cover the same lesion length.     

冠状动脉内长和短支架及多个支架置入后再狭窄的血管造影随访研究

目的　比较单个短和长支架及多个支架置入的远期血管造影再狭窄发生率。方法　回顾性分析1996年5月至1998年10月在我院接受冠状动脉内支架置入并有血管造影随访的77例病人的临床及血管造影资料。单个短支架组（A组支架长度≤20mm）37例,39支血管;单个长支架组（B组支架长度>20mm）22例,25支血管;多个支架组（C组）18例,18支血管置入39个支架。结果　　病变长度在B和C组明显长于A组［（23.66±12.78)mm和(26.42±13.60)mm与(10.30±4.67)mm,P<0.001］;支架长度C组>B组>A组,P<0.001和0.002。随访时最小管腔开放直径(MLD)和管腔晚期丢失在A和C组间有明显差异,P<0.01和0.02,而在A和B组,B和C组间无统计学差异。三组的再狭窄率分别为28.2%、36%和61.1%,C组明显高于A组（P<0.05）,而B组又高与A组、C组高于B组的趋势,但统计学上无明显差异。Logistic多因素回归分析证实多个支架置入是再狭窄的唯一的独立预测因素（OR=3.29,P<0.05）。结论　多个冠状动脉内支架置入是发生晚期血管再狭窄的唯一独立预测因素;而与单个短支架置入相比,单个长支架置入的再狭窄率也有增高的趋势。     

Angiographic and clinical outcomes of a pharmacokinetic study of sirolimus-eluting stents: lesson from restenosis cases.

BACKGROUND: A pharmacokinetic (PK) study was conducted to evaluate sirolimus-eluting stents (SES) in Japanese people, representing the first clinical trial of the use of drug-eluting stents in Japan. METHODS AND RESULTS: The PK study was conducted in 20 patients with 30 lesions treated with sirolimus-coated BX Velocity stents. All lesions were treated with a single SES (3 x 18 mm). Angiographic follow-up was performed at 8 months after SES implantation, and the clinical outcomes were evaluated at 1 year in all cases. All procedures were successful, and all patients were discharged without any adverse cardiac events. The total restenosis rate was 10% (3 lesions) and target vessel revascularization was performed in those 3 cases (15%). Restenoses occurred at the proximal and distal stent margins. Intravascular ultrasound examination of restenosis cases revealed abundant plaque burden at the stent edges even though the luminal area was preserved. CONCLUSIONS: The sirolimus-eluting BX Velocity stent is safe and useful for Japanese patients with coronary artery disease. However, restenosis at proximal stent edge seems to be a problem.     

Sirolimus-eluting stents associated with paradoxic coronary vasoconstriction

OBJECTIVES: The purpose of the present study was to assess coronary vasomotor response to exercise after sirolimus-eluting stent (SES) implantation. BACKGROUND: Sirolimus-eluting stents have been shown to markedly reduce the incidence of angiographic and clinical restenosis. However, long-term effects of sirolimus on endothelial function are unknown. METHODS: Coronary vasomotion was evaluated with biplane quantitative coronary angiography at rest and during supine bicycle exercise in 25 patients with coronary artery disease. Eleven patients were treated with a bare-metal stent (BMS) (control group) and 14 patients underwent SES implantation (sirolimus group) for de novo coronary artery lesions. Both groups were studied 6 +/- 1 month after the intervention. Minimal luminal diameter; stent diameter; and proximal, distal, and reference vessel diameter were determined. RESULTS: The reference vessel showed exercise-induced vasodilation (+13 +/- 4%) in both groups. Vasomotion within the stented vessel segments was abolished. In controls, the adjacent segments proximal and distal to the stent showed exercise-induced vasodilation (+15 +/- 3% and +17 +/- 4%, respectively). In contrast, there was exercise-induced vasoconstriction of the proximal and distal vessel segments adjacent to SESs (-12 +/- 4% and -15 +/- 6%, respectively; p < 0.001 vs. corresponding segments of controls). Sublingual nitroglycerin was associated with maximal vasodilation of the proximal and distal vessel segments in both groups. CONCLUSIONS: Implantation of a BMS does not affect physiologic response to exercise proximal and distal to the stent. However, SESs are associated with exercise-induced paradoxic coronary vasoconstriction of the adjacent vessel segments, although vasodilatory response to nitroglycerin is maintained. These observations suggest (drug-induced) endothelial dysfunction as the underlying mechanism.     

Incomplete expansion of Palmaz-Schatz stents despite high-pressure implantation technique: impact on target lesion revascularization.

Improved expansion of stents using high-pressure implantation technique with subsequent antiplatelet therapy has improved patient outcome regarding the incidence of subacute stent thrombosis, bleeding complications and restenosis. Whether high-pressure implantation per se guarantees adequate stent expansion remains unclear. The aim of the study was to determine (1) stent expansion after high-pressure implantation technique and (2) whether stent expansion influences rate of target lesion revascularization within 6 months of follow-up. One hundred Palmaz-Schatz stents were implanted in 98 lesions (91 native vessels, 7 graft vessels) of 94 patients using high-pressure implantation technique (balloon pressure 12-20 atm). Stent expansion was investigated using intravascular ultrasound imaging (IVUS). Clinical follow-up of the patients was performed for 6 months. After implantation, stent/mean reference ratio was 0.81 +/- 0.16. Noncompliant balloons used for implantation were chosen by angiographic criteria. Mean balloon/reference ratio was 1.08 +/- 0.22; therefore balloons were not undersized. Additional balloon dilataion using higher pressures and/or larger balloons based on IVUS criteria and subsequent IVUS measurements was performed in 52 patients (55%); in these patients, stent expansion improved from 79 +/- 16 to 91 +/- 15% (mean +/- SD) of average reference areas (p < 0.002). Within the 6 months' clinical follow-up, target lesion revascularization was performed in 19 patients (20%). The only prognostic factors for the development of in-stent restenosis requiring target lesion revascularization were the vessel size (p < 0.05) and the extent of plaque distal to the stents (p < 0.05). Implantation of Palmaz-Schatz stents using high-pressure technique does not guarantee adequate stent expansion. Additional dilatation with higher pressures and/or larger balloons improves stent expansion. The size of the stented vessel and the extent of plaque at the distal stent end (residual outflow stenosis) but not the degree of stent expansion were predictors for target lesion revascularization within 6 months' follow-up.     

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.     

Cobalt-chromium stents in long lesions of large vessels: clinical and angiographic results

Although drug-eluting stents have reduced the restenosis rate, some patients are not good candidates for prolonged double-antiplatelet therapy. Our goal was to learn the results of implanting cobalt-chromium stents in long lesions of large vessels.All consecutive patients with ≥1 lesion treated with a cobalt-chromium stent ≥28 mm in length and ≥3.5 mm in diameter during a 12-month period in 2 centers were monitored clinically and angiographically to determine the clinical status, restenosis rate, pattern of restenosis, and need for revascularization.The series comprised 78 patients with 81 lesions, mean age, 62.6 ± 15.2 yr; diabetes mellitus,19.2%; and primary or rescue intervention, 20.6%. Target vessels were the left anterior descending coronary artery, 12 (14.8%); left circumflex coronary artery, 12 (14.8%); and right coronary artery, 57 (70.4%). The mean lesion length was 35.18 ± 12.65 mm. The proximal reference diameter after percutaneous coronary intervention was 3.64 ± 0.54 mm; the distal, 3.2 ± 0.43 mm; and the mean, 3.42 ± 0.44 mm. The mean stent length was 38.05 ± 12.78 mm (range, 28-90 mm). The binary restenosis rate was 23% (15/64), with pattern IB in 2 cases, IC in 5, II in 7, and IV in 1. Revascularization was needed in 6 patients.In treating long lesions of large vessels, we found that cobalt-chromium stents achieved a moderate rate of target-vessel restenosis and a low rate of repeat revascularization. The pattern of restenosis was focal in almost half of the cases, and, in most remaining cases, restenosis affected short segments of the vessel.     

雷帕霉素洗脱支架治疗支架内再狭窄的临床及冠状动脉造影随访观察

目的评价雷帕霉素洗脱支架(商品名Cypher支架,强生公司产品)治疗支架内再狭窄的疗效及安全性。方法27例支架内再狭窄且有临床缺血症状的患者接受了Cypher支架治疗,其中23例患者的支架内再狭窄为弥漫、复杂病变,有5例同时置入了2个Cypher支架。术后对所有患者进行临床随访及冠状动脉造影复查。结果所有支架均成功置入,无残余狭窄或残余狭窄<10%,未见任何并发症。平均随访时间8.9±2.1(5～14)年,临床随访率96.3%,造影随访率92.6%。随访期间,无一例患者死亡。有1例支架近端边缘节段血管发生了再狭窄导致临床心绞痛复发,2例支架近端边缘节段有轻微的新生内膜增殖,但狭窄程度<25%,其余24例均无明显的晚期管腔丢失。本组支架内平均晚期管腔丢失(0.09±0.02)mm、支架远端边缘节段(0.10±0.03)mm、支架近端边缘节段(0.20±0.06)mm。靶血管血运重建率3.8%。结论Cypher支架治疗支架内再狭窄安全、可行,它能有效防止这类病变的新生内膜增殖和再次再狭窄。     

Comparison of immediate and follow-up results of the short and long NIR stent with the Palmaz-Schatz stent.

The intrinsic characteristics of a stent including stent length may affect both procedural success and long-term outcome. The present study evaluated the immediate and follow-up results after implantation of the short and long NIR stent and compared these results with the Palmaz-Schatz stent. Between July 1995 and December 1996, stenting with a 16-mm NIR stent (NIR-16), a 32-mm NIR stent (NIR-32), or a Palmaz-Schatz stent (PS) was performed in 68, 57, and 155 lesions, respectively. There were no significant differences in the incidences of delivery failure (PS, 2.6%: NIR-16, 4.4%; NIR-32, 5.3%; p = NS) and procedural success (PS, 92%; NIR-16, 93%; NIR-32, 93%; p = NS) among the 3 groups. The reference vessel diameter was smaller in lesions with a 32-mm NIR stent than in those with a Palmaz-Schatz stent (PS, 3.14+/-0.58, NIR-16, 3.00+/-0.50; NIR-32, 2.90+/-0.47 mm; p <0.05). The lesion length was longer in lesions with a 32-mm NIR stent than in those with a Palmaz-Schatz or a 16-mm NIR stent (PS, 8.9+/-5.0; NIR-16, 11.0+/-4.1; NIR-32, 26.1+/-9.7 mm; p <0.01). After the procedure, the lesions with a 32-mm NIR stent had a smaller minimal lumen diameter than those with a Palmaz-Schatz stent (PS, 3.17+/-0.61; NIR-16, 2.99+/-0.51; NIR-32, 2.89+/-0.49 mm; p <0.01). At follow-up, a smaller minimal lumen diameter was observed in lesions with a 32-mm NIR stent than in those with a Palmaz-Schatz or a 16-mm NIR stent (PS, 2.32+/-0.98; NIR-16, 2.25+/-0.80; NIR-32, 1.68+/-0.79 mm; p <0.01). Restenosis rates were 16.5% in lesions with a Palmaz-Schatz stent, 13.3% in those with a 16-mm NIR stent, and 47.4% in those with a 32-mm NIR stent (p <0.01). Although stent delivery and procedural success of a long NIR stent were acceptable, the restenosis rate of a long NIR stent was high compared with a short NIR stent or a Palmaz-Schatz stent.     

Intravascular ultrasound assessment of expansion of the sirolimus-eluting (cypher select) and paclitaxel-eluting (Taxus Express-2) stent in patients with diabetes mellitus

Patients with diabetes have a higher risk for in-stent restenosis after coronary stent implantation. Drug-eluting stents (DES) are highly effective in reducing in-stent restenosis. Once neointimal hyperplasia is suppressed with DES, the impact of stent underexpansion becomes magnified. The aim of this study was to evaluate DES expansion in patients with diabetes. Ninety-five patients with diabetes were randomized to Cypher Select (n = 48) or Taxus Express-2 (n = 47) stent implantation. Intravascular ultrasound was performed after stent implantation. Stent expansion was defined as the ratio of measured to predicted minimum stent diameter. There was a trend for lower stent expansion in the Cypher Select stent group (0.74 +/- 0.08 vs 0.78 +/- 0.11 in the Taxus Express-2 stent group, p = 0.061). Cypher Select stents achieved a final minimal stent cross-sectional area of 5.5 +/- 1. 8 mm2, compared with 6.4 +/- 1.9 mm2 for Taxus Express-2 stents (p = 0.015). For stents with nominal diameters > or =2.75 mm (Cypher Select n = 40, Taxus Express-2 n = 38), 42.5% of the Cypher Select stents and 10.5% of the Taxus Express-2 stents did not achieve a final minimum stent area of 5 mm2 (p = 0.002). Insulin treatment (relative risk 0.31, 95% confidence interval 0.10 to 0.95, p = 0.041) and stent type (relative risk 0.15, 95% CI 0.04 to 0.53, p = 0.003) were independent predictors of not achieving a minimum stent area >5.0 mm2. In conclusion, an important percentage of DES in patients with diabetes fail to achieve the manufacturers' predicted final minimal stent diameter. Cypher Select stent and insulin treatment were independent predictors of not achieving a minimum stent area >5.0 mm2.     

Long-term outcome of simultaneous kissing stenting technique with sirolimus-eluting stent for large bifurcation coronary lesions.

OBJECTIVES: This study was conducted to evaluate the outcomes of simultaneous kissing stenting with sirolimus-eluting stent (SES). BACKGROUND: Percutaneous intervention for bifurcation coronary lesions is still challenging. METHODS: This study was designed to evaluate the long-term outcomes of 36 consecutive patients with large bifurcation coronary lesions who underwent simultaneous kissing stenting with SES. RESULTS: Lesion location was unprotected left main in 29 patients (81%) and anterior descending artery in 7 (19%). The patients received a combination of aspirin and clopidogrel for 6 months and cilostazol for 1 month. Mean proximal reference diameter was 4.05 +/- 0.68 mm. Compared with the side branch (SB), the main vessel (MV) involved longer lesions (25.8 +/- 17.0 mm vs. 10.2 +/- 10.8 mm, P < 0.001) and smaller preprocedural minimal lumen diameters (1.02 +/- 0.53 mm vs. 1.46 +/- 0.78 mm, P = 0.006) and was treated with larger stents (3.1 +/- 0.3 mm vs. 3.0 +/- 0.3 mm, P = 0.006). Angiographic success rate was 100%. Over the follow-up of 26.7 +/- 8.6 months, no deaths, myocardial infarctions or stent thromboses occurred. Target lesion revascularization was performed in five patients (14%). Overall angiographic restenosis occurred in 5/30 patients (17%), consisting of 4 (13%) at MV and 3 (10%) at SB. At follow-up angiography, a membranous diaphragm at the carina was identified in 14 patients (47%), but only one of whom was associated with angiographic restenosis. CONCLUSION: Simultaneous kissing stenting with SES appears a feasible stenting technique in large bifurcation coronary lesions. However, a new angiographic structure of carinal membrane developed in a half of patients at follow-up and its influence needs to be further investigated.     

Short stent implantation for routine use is feasible in a high proportion of coronary interventions and yields a low restenosis rate

Stent length predicts restenosis. The feasibility of using a short stent (<10 mm) routinely was investigated in 331 consecutive patients treated for 424 coronary artery lesions. A single short stent provided suitable coverage and achieved a residual stenosis <30%, with or without predilatation, in 252/424 lesions (59.4%). Longer stents were implanted in 58/424 lesions (13.7%), while only percutaneous transluminal coronary angioplasty was performed in 114/242 lesions (26.9%). Angiographic success and procedural success were achieved in 250/252 lesions (99.2%). Restenosis occurred in 36/231 lesions (15.6%) after short stenting, in 10/53 lesions (18.9%) after long stents, in 21/88 lesions (23.9%) after percutaneous transluminal coronary angioplasty, and in 67/372 lesions (18.0%) controlled angiographically. Only small vessel diameter predicted restenosis after short stenting. Thus, a single short stent implanted directly or after predilatation is sufficient to achieve an acceptable angiographic result in more than in nearly 60% of all treated lesions. Short stenting results in a low restenosis rate.     

Comparison of the self-expanding Radius stent and the balloon-expandable Multilink stent for elective treatment of coronary stenoses: a serial analysis by intravascular ultrasound.

We compared the outcome of the self-expanding Radius stent and the balloon-expandable Multilink stent serially by angiography and intravascular ultrasound. Successful stent deployment was achieved in 66 lesions of 56 stable angina patients (34 lesions with Radius stents and 32 lesions with Multilink stents). At follow-up, there were no significant differences in minimal lumen diameter or percent diameter stenosis between the groups, nor in restenosis rates, although the Radius stent group rate was slightly lower (23.5% vs. 31.3%). In the Radius stent group, stent cross-sectional area (CSA) increased gradually after implantation until the 6-month follow-up (8.37 +/- 1.83 to 10.16 +/- 2.59 mm(2); n = 15), giving a larger CSA (P = 0.03) than the Multilink stent group, which decreased (9.00 +/- 2.05 to 8.27 +/- 2.15 mm(2); n = 17). The lumen CSA was also slightly larger (6.82 +/- 3.06 vs. 5.84 +/- 1.85 mm(2); P = 0.29) in the Radius stent group. These findings indicated that the Radius stent enlarged progressively after implantation, which might be useful for prevention of restenosis.     

Clinical and angiographic follow-up after long versus short stenting in unselected chronic coronary occlusions

BACKGROUND: Few data are available on the efficacy of long stenting for lesions in unselected chronic total occlusion (CTO). HYPOTHESIS: The study was undertaken to evaluate the angiographic restenosis and long-term clinical outcomes after long stent implantation in patients with CTO. METHODS: Our retrospective analysis includes a consecutive series of stent implantation in 220 patients with CTO. We compared angiographic restenosis, target lesion revascularization, and long-term clinical outcomes of short stenting (< 20 mm, Group 1, n = 113) with a concurrent series of long stenting (> or = 20 mm, Group 2, n = 107). RESULTS: Angiographic follow-up was obtained in 174 patients (79.5% of those eligible), and the rates of angiographic restenosis were 19.3% in Group 1 and 33.7% in Group 2 (p < 0.05). In multivariate analysis, the postinterventional minimal lumen diameter was the only independent predictor of restenosis (odds ratio = 0.20, 95% confidence interval 0.08-0.49, p < 0.01). The angiographic restenosis rate was significantly lower in Group 1 than in Group 2 in patients with final minimal lumen diameter < 3.0 mm (28.9 vs. 55.9%, respectively, p < 0.05). However, the angiographic restenosis rate was not significantly different between the two groups in patients with final minimal lumen diameter > or = 3 mm (12.0 vs. 19.2%, respectively, p = NS). During the follow-up (29.1 +/- 10.8 months), there was no difference between the two groups in death, nonfatal myocardial infarction, and target lesion revascularization. CONCLUSIONS: The use of long (> or = 20 mm) versus short (< 20 mm) stents in patients with CTO is associated with a higher angiographic restenosis rate, but there is an equivalent risk of restenosis in selected patients with relatively large-sized vessels.