NIR Stent Research Articles

A Randomised Trial of Endoluminal Reconstruction Comparing the NIR Stent and the Wallstent in Angioplasty of Long Segment Coronary Disease: Results of the RENEWAL Study

Background The role of coronary stents in reducing the incidence of acute complications and late restenosis after angioplasty has been established in randomized studies focusing on simple, short coronary lesions. The development of long coronary stents has provided a safe and predictable means of treating long coronary lesions, but this carries with it a higher risk of restenosis. By comparing the outcome of treating long lesions with two different stent types, we aimed to assess the influence of stent design rather than the nature of long lesions per se on the relatively high restenosis rates in this subgroup. Methods This study was designed to assess procedural complications and 6-month restenosis rates in a randomized trial comparing a slotted tube stent with a self-expanding stent for the treatment of long coronary lesions. Randomization of vessels to either stent occurred after successful balloon angioplasty. Intravascular ultrasound (IVUS) was used to assess and optimize stent deployment. The patients were restudied angiographically and by IVUS at 6 months. Results A total of 82 patients (85 vessels) were recruited (slotted tube stent, n = 44 vessels; self-expanding stent, n = 41 vessels). Successful deployment occurred in 41 (100%) of 41 of the self-expanding stent group and 41 (93%) of 44 of the slotted tube stent group. There was no difference in lesion length between the two groups (slotted tube stent, 26.6 ± 6.9 [SD] mm; self-expanding stent, 28.7 ± 9.8 [SD] mm; P = .2), but the mean length of the self-expanding stent was greater than that of the slotted tube stent (41.6 ± 18.8 [SD] mm vs 35.4 ± 16.2 [SD] mm, respectively; P < .05). There was no significant difference in the rate of major events between the two groups at 6-month follow-up. The angiographic restenosis rate at follow-up was less in the slotted tube stent group, but this did not reach statistical significance (26% vs 46%, respectively; P = .1) and the target lesion revascularization rate was similar for both groups (7.9% vs 7.7%, respectively; P = .8). IVUS assessment of plaque/stent ratios suggested a greater plaque burden in the self-expanding stent compared with the slotted tube stent at follow-up (0.42 ± 1.2 [SD] vs 0.3 ± 0.08 [SD]), but this was not statistically significant (P = .1). Conclusions Long stents can be safely and successfully deployed in long segment coronary disease, with an acceptable 6-month target lesion revascularization rate. Our results showed a trend toward lower angiographic restenosis and a lesser in-stent plaque burden at follow-up in the slotted tube stent compared with the self-expanding stent. This suggests that stent design may influence the restenotic process in long coronary lesions. (Am Heart J 2001;141:971-6.)

Gold-coated NIR stents in porcine coronary arteries.

As endovascular stents are altered to add functionality, eg, by adding radiopaque coatings, biocompatibility may suffer. We examined the vascular response in porcine coronary arteries to stainless steel gold-coated NIR stents (7-cell, Medinol, Inc). Stents, 9 and 16 mm in length, were left bare or coated with a 7-microm layer of gold. Physical and material effects were examined in four different gold-coated stent types, two at each length that either had the coating applied to the standard strut, ie, gold coated thicker than controls, or had the coating applied to thinned struts, ie, gold coated of the same thickness as control struts. Simple gold coating exacerbated intimal hyperplastic and inflammatory reactions over 28 days, but postplating thermal processing smoothed the coating surface and negated the adverse tissue response to gold. The relative amounts of base steel and gold coating and their resistances to expansion and collapse determined the extent of stent recoil. Gold coatings enhance the radiopacity of steel stents, but not without effects on vascular repair. Material effects predominate and can be abrogated by heating coated stents to alter surface finish and material purity. Clinical results may suffer unless consideration is given to material and physical effects of gold.

Final results of a randomized trial comparing the NIR stent to the Palmaz-Schatz stent for narrowings in native coronary arteries

The NIR stent is a novel second generation tubular stent that was designed to overcome some of the limitations of the earlier Palmaz-Schatz (PS) stent design. The NIR Vascular Advanced North American (NIRVANA) trial randomized 849 patients with single coronary lesions to treatment with the NIR stent or the PS stent. The study was an “equivalency” trial, designed to demonstrate that the NIR stent was not inferior to (i.e., equivalent or better than) the PS stent, for the primary end point of target vessel failure (defined as death, myocardial infarction, or target vessel revascularization) by 9 months. Successful stent delivery was achieved in 100% versus 98.8%, respectively, with a slightly lower postprocedural diameter stenosis (7% vs. 9%, p = 0.04) after NIR and PS stent placement, respectively. Major adverse cardiac events (death, myocardial infarction, repeat target lesion revascularization) were not different at 30 days (4.3% vs. 4.4%). The primary end point of target vessel failure at 9 months was seen in 16.0% of NIR versus 17.2% of PS patients, with the NIR proving to be equal or superior to the PS stent (p <0.001 by test for equivalency). Angiographic restudy in 71% of a prespecified cohort showed no significant difference in restenosis (19.3% vs 22.4%). Thus, the NIR stent showed excellent deliverability with slightly better acute angiographic results and equivalent or better 9-month target vessel failure rate when compared with the PS stent.

Acute and Long-term Clinical Outcomes after Coronary Stenting of CrossFlex, GFX and NIR Stents

Background and Objectives:New coronary stents are displacing a for the broader array of lesions. However, some controversy but disagreement remains as to which device is more advantageous and whether the design determines outcomes. The present study investigated investigates the impact of the stent design on the early and one year outcomes. Materials and Method:A retrospective analysis of 350 patients with 378 lesions (60±10 years, 265 male), who that underwent 181 CrossFlex, 95 GFX, 102 NIR coronary stentings at Chonnam National University Hospital from January 1996 to December 1999, was performed. The early procedural success rates, major adverse cardiac events (MACE) within one year and the follow-up angiographic findings in 227 patients (240 lesions, follow-up duration=8.1±5.9 months) among the three groups were compared among three groups. Results:There were no significant differences in the baseline clinical and angiographic characteristics except in the lesion length (CrossFlex:GFX:NIR=11.5±5.2:14.5±6.7:13.9±5.7 mm, p<0.05). There were no significant differences in the early angiographic success rates among the three groups (CrossFlex:98.9%, GFX:100.0%, NIR:99.0%). There were no significant differences in the late luminal loss (CrossFlex:GFX:NIR=1.03±0.69:1.11±0.75:1.09±0.70 mm, p=NS), the restenosis rates (CrossFlex:30.6%, GFX:30.8%, NIR:28.4%, p=NS) and MACE (CrossFlex:GFX:NIR=27.6%:29.5%: 27.5%, p=NS) among the three groups. Conclusion:Despite the different lesions lengths, the early and late angiographic outcomes, and MACE within one year were not different among three different types of coronary stents. (Korean Circulation J 2001;31(10):1004-1012)

Evolución hospitalaria y a medio plazo en pacientes tratados con implante de stent NIR: experiencia del registro multicéntrico ESPORT-NIR

Despite improvements in the results and techniques of catheter-based revascularization, few studies have evaluated the clinical results of the application of new stent designs. We describe the in-hospital and mid-term outcome of patients undergoing a stent NIR implantation. At least 1 Stent NIR was implanted in 1.004 patients (1.136 lesions) recruited from 50 centers in an international, multicenter, prospective, registry (Spain and Portugal NIR stent registry). Inclusion criteria were objective coronary ischemia related to a severe de novo lesion or first restenosis in native vessels with a reference diameter >= 2.75 mm. The primary end-point was the incidence of major adverse cardiac events within the first 7 months of follow-up. The mean age of the patients was 60 years and 82% were male. Angioplasty was indicated due to unstable angina in 61% of the cases. Stent implantation was successfully achieved in 99.6%. Clinical success (angiographic success without in-hospital major events) was achieved in 98.6% of patients. The rate of angiographic restenosis (> 50% stenosis narrowing) was 16% (CI 95%; 11.7-21.2). The accumulated major cardiac adverse event rate at seven months of follow-up was 8.7%: death (0.9%), acute myocardial infarction (1.2%) and target lesion revascularization (6.6%). In the wide setting of the population included in the ESPORT-NIR registry, stent NIR implantation was a highly effective therapy with a good mid-term clinical and angiographic outcome.

Effects of stent design on side branch occlusion after coronary stent placement

This study was performed to assess the immediate and long-term patency of stent-associated side branches (SB) according to the types of stent. A total of 314 patients with 332 lesions (CrossFlex stent 86, NIR 100, GFX 146) had 365 SB (>1 mm) covered by coronary stents. Side branch occlusion (SBO) occurred in 7.7% of CrossFlex stent, in 10.5% of NIR stent and in 8.8% of GFX stent (P = NS). SBO primarily occurred in SB with ostial disease, and the presence of SB ostial disease was the only independent predictors of SBO after stenting (OR 22.1, 95% CI 9.47-51.49, P < 0.001). At 6 months follow-up, 11 of 31 SBO regained the patency, but the remaining SB had persistent SBO. Delayed SBO occurred in 8 SB, being associated with the presence of SB ostial disease and in-stent restenosis. In conclusions, SBO was not associated with the types of stent design, but with the SB lesion morphology.

Which Stent Should Be Regarded as the Gold Standard for Treatment of Coronary Artery Stenoses?

Coronary stenting using the first-generation Palmaz-Schatz stent in patients with ischaemic heart disease has proved efficient compared with balloon angioplasty. The objective of the DANSTENT study is to evaluate the clinical and angiographic outcome of implantation of a second-generation slotted-tube stent in coronary artery lesions. The DANSTENT study is a randomised multicentre trial comparing procedural success, clinical outcome and angiographic determination of the minimal lumen diameter and frequency of restenosis in the target vessel 6 months after implantation of a 15-mm Palmaz-Schatz or a 16-mm second-generation rigid-flex NIR stent. Both stents are hand-crimped onto balloons and deployed at high pressure. All angiograms will be evaluated by a core laboratory. The relationship between polymorphism of the angiotensin-converting enzyme gene and the occurrence of coronary restenosis will also be investigated. More than 450 patients will be included in the study, which will determine the level of coronary restenosis at 6-month follow-up and the clinical outcome 6 and 12 months after implantation of the stents. Sub-study analyses will evaluate possible differences between the two groups with regard to the size of the target vessel and total number of coronary occlusions.

A new rat model of small vessel stenting.

Restenosis is the major complication of coronary angioplasty and stenting. In addition, the small vessel diameter represents a major limitation to the wide use of the technology. The aim of this study was to assess the feasibility and the vascular response of stent deployment in rat small vessels. In 40 Wistar rats (500-550 g) a Nir stent crimped on a 1.5 mm Comet angioplasty balloon catheter was deployed at high pressure in the common carotid artery. Neointimal area, neointima/media ratio and the arterial dimension were assessed immediately and at 7, 14, 21, and 28 days after stenting. After stent deployment, the neointimal area and the neointima/media ratio increased progressively and peaked at 14 days (p < 0.05 vs 0 and 7 days). Alpha-actin-positive cells were found circumferentially organized on the lumen surface. At 21 and 28 days after stenting, the neointima and the neointima/media ratio were not statistically different compared with the results obtained fourteen days after stent deployment. No significant differences in the area of external elastic lamina were observed during the study period. In contrast, the internal lumen area was reduced significantly at 14, 21, and 28 days after the stent deployment. Subacute thrombosis rate after stent implantation was 26.5 %. The results of this study demonstrated that the balloon expandable stents can be safely placed into rat arteries and the reduction of the internal arterial lumen observed after stent deployment was only due to the neointima formation whereas remodeling did not occur.

Directional Coronary Atherectomy of In-stent Restenosis: A Two-Center Experience

Background: Tissue proliferation is the major cause of in-stent restenosis (ISR). Thus, debulking of material should be the most favorable method to treat ISR. The present study was performed to test the clinical and angiographic outcome of directional coronary atherectomy (DCA) in the treatment of restenosis within different stents. Methods and Results: Fifty patients with ISR in single stents (12 Palrnaz-Schatz stents, 8 Pura stents, 10 Multilink stents, 10 NIR stents, 8 Wallstents, and 2 Microstents) underwent DCA with adjunctive balloon angioplasty in 38 patients. Primary success was achieved in 48 patients (96%). Two patients developed CK-MB elevations, one with a Q-wave infarction. Some minor technical problems occurred with respect to the different stent types. The percent diameter stenosis decreased from 76 ± 7% at baseline to 29 ± 6% after atherectomy (P < 0.0001) and 20 ± 4% after adjunctive PTCA, and it increased to 45 ± 19% at 4-month angiography (P < 0.0001). Angiographic restenosis occurred in 14 (29.2%) of 48 patients who were reevaluated after 4 months. Conclusion: While DCA is able to remove u significant amount of intimal tissue in selected patients with in-stent restenosis, new atherectomy catheter designs are required to make this a feasible and safe procedure.

Clinical experience with the NIR stent: Retrospective observation on acute results and follow-up in 709 patients

Clinical experience with the NIR stent: Retrospective observation on acute results and follow-up in 709 patients

Chronic Stent Recoil of Different Design of Stents: An Intravascular Ultrasound Study

Background:The chronic stent recoil of Palmaz-Schatz stent was minimal. However, the chronic stent recoil of other types of stents has not been determined. We evaluated the chronic stent recoil of different design of stents. Methods:Serial (after stent implantation and follow-up) intravascular ultrasound images using automatic transducer pullback devices were obtained in 70 native coronary artery lesions;slotted-tube design of PalmazSchatz stent 30 and NIR 10, sinusoidal ring design of GFX 20, and coil design of CrossFlex 10. Measurements of stent cross-sectional area (CSA) (4 image slices in Palmaz-Schatz stent and 7 image slices in GFX, NIR and CrossFlex) using computerized planimetry were performed. Stent CSA post-stenting and follow-up was compared to evaluate the chronic stent recoil of different designs of stent. The chronic stent recoil (%) was defined as (post-intervention–follow-up) stent CSA×100/post-intervention stent CSA. Results:The changes of stent CSA between post-intervention and follow-up period were minimal in NIR stent, Palmaz-Schatz and GFX. However, there was significant reduction of stent CSA in CrossFlex stent. Compared with other types of stents, the changes of stent CSA were significantly larger in CrossFlex stent (p=0.001). The chronic stent recoil was significantly larger in CrossFlex stent than in other types of stents (4.0±6.0% vs 0.7±5.8% in GFX stent, 0.4± 5.0% in Palmaz-Schatz and 0.3±3.0% in NIR, p=0.001, respectively). There were no significant differences of chronic stent recoil among GFX, NIR and Palmaz-Schatz stent. Conclusions:The chronic stent recoil was minimal in slotted-tube and sinusoidal ring designs of stent. However, there was significant chronic stent recoil in coil design of stent. (Korean Circulation J 2000;30(1):16-22)

The Early Result of Primary NIR Stenting in Acute Myocardial Infarction

Background and Objectives:The intracoronary stent may be useful in the preventing of abrupt closure and coronary restenosis after coronary angioplasty, and recently primary stenting has been one of therapeutic modalities. We assessed the clinical and angiographic results of primary NIR stenting in patients with acute myocardial infarction (AMI). Materials and Methods:Between November 1997 to January 1999, 55 stentings with NIR stents were done in 51 patients with acute myocardial infarction. Angiographic follow-up was available at 7±2.3 days in 35 patients. Results:1) Among 51 patients (M/F:37/14), 44 patients had Qwave MI (86%), 7 patients had non-Q-wave MI (14%). 2) The mean age was 61±12.4 years (range:26 to 82 years). 3) The mean time from the onset of chest pain to the arrival at emergency room was 4.6±4.2 hours. The mean door-to-balloon time was 93±46 minutes 4) Treated vessels were as follows;28 in LAD, 17 in RCA, 10 in LCX. 5) The indications for stent implantation were suboptimal angiographic results after PTCA in 38 lesions (69%), dissection in 9 lesions (16%), abrupt vessel closure in 1 lesion and elective in 7 lesions (13%). 6) Single stent implantation was done in 47 patients. Overlapping stents were done in 4 patients. 7) A procedure related complication occurred in one patient, peri-stent dissection without flow limitation. 8) Full expansion of the stent failed in three lesions with coronary calcifications and the residual stenosis was 35, 40, 50% in each case. In these cases, in-stent thrombus was not demonstrated in follow up angiography. 9) The minimal lumen diameter increased from 0.11±0.39 to 2.96±0.40 mm. 10) Angiographic follow-up on 38 stents in 35 patients demonstrated in-stent thrombus in 3 stents, in-stent restenosis in 1 stent. But in-stent flow limitations were not found in these 4 cases and TIMI III flow were maintained. Patients with Q-wave MI and coronary thrombus on initial angiography were more prone to subacute thrombosis. Conclusion:The NIR stent could be used successfully in primary coronary stenting in acute myocardial infarction. The present study shows relatively low risk of subacute stent thrombosis. The rate of restenosis needs to be confirmed by long term study. (Korean Circulation J 2000;30(5):563-570)

Clinical and angiographic results with the NIR stent: First International NIR Endovascular Stent Study (FINESS-II).

BACKGROUND: Although safety and efficacy of the NIR trade mark stent have been reported, the long-term angiographic and clinical outcomes have yet to be investigated. The FINESS-II study (First International NIR Endovascular Stent Study) was designed to assess the procedural safety of single 9 and 16 mm NIR stent implantation, the six-month restenosis rate and finally the six- and 12-month clinical outcome of patients treated with this novel coronary stent. METHODS: Patients with angina and a single de novo lesion in a native coronary artery of >3 and <5 mm diameter were included in this multicentre, prospective, observational trial. Clinical follow-up was obtained at one, six and 12 months. Angiography was performed before and after the stent implantation and at six months. The primary endpoint included major adverse cardiac events (death, myocardial infarction and target lesion revascularization) within 30 days after the procedure. Major bleeding complications and subacute stent thrombosis within the first 30 days were also reported as specific endpoints. Secondary endpoints were major cardiac-event-free survival at six- and 12-month follow-up and angiographic restenosis at six months. RESULTS: A total of 156 patients (81% male, mean age 60 +/- 10 years), with stable (54%), unstable (40%) angina pectoris or silent ischemia (6%) were enrolled. The target vessel diameter was 2.94 +/- 0.54 mm. The minimal lumen diameter pre, post and at follow-up was 1.04 +/- 0.32 mm, 2.64 +/- 0.42 mm and 1.88 +/- 0.63 mm, respectively. Restenosis rate according to the >50% diameter stenosis criterion at six month follow-up was 19% (26/136). At 12 months, the event-free survival rate was 83% (two deaths, one Q-wave and three non-Q-wave myocardial infarctions, four bypass surgery and 17 target lesion revascularizations), while 87% of the patients were free of angina pectoris. CONCLUSION: the outcome of the FINESS-II trial is comparable to those observed in previous stent trials (Benestent II), indicating that the coronary NIR stent is safe and effective as a primary device for the treatment of native coronary artery lesions in patients with (un)stable angina pectoris.

Coronary bifurcation stenting using dedicated bifurcation stents

We report three cases of successful implantation of three different stents specially designed for bifurcation lesions, guided by intracoronary ultrasound. The BARD and AVE are true bifurcated stents for side-branch access and the NIR-Side Royal is a single modified NIR stent with an aperture to allow provisional bifurcation stenting. These designs introduce a new era in percutaneous management of coronary bifurcation lesions. Cathet. Cardiovasc. Intervent. 49:105-111, 2000.

Three-dimensional intravascular ultrasonic volumetric quantification of stent recoil and neointimal formation of two new generation tubular stents

Currently, several different designs of coronary stents are available. However, only a few of the new generation stents have been investigated in large randomized trials. Mechanical behavior of first-generation stents (Palmaz-Schatz, Gianturco-Roubin) may not be applied to the new designs. We investigated the chronic mechanical behavior (recoil) of 2 stents recently approved by the Food and Drug Administration (MULTILINK and NIR). Forty-eight patients with single-stent implantation (23 MULTILINK and 25 NIR) were assessed by means of volumetric 3-dimensional intravascular ultrasound analysis after the procedure and at 6-month follow-up. In addition, volumetric assessment of neointimal formation was performed. No significant chronic stent recoil was detected in both groups (Δ MULTILINK stent volume: +5.6 ± 41 mm 3 [p = NS] and Δ NIR stent volume + 2.1 ± 26 mm 3 [p = NS]). A similar degree of neointimal formation at 6 months was observed between the 2 stents (MULTILINK 46 ± 31.9 mm 3 vs NIR 39.9 ± 27.6 mm 3, p = NS). In conclusion, these 2 second-generation tubular stents did not show chronic recoil and appeared to promote similar proliferative response after implantation in human coronary arteries.

Intravascular ultrasound comparison of chronic recoil among different stent designs

Intravascular ultrasound studies were acquired in 70 native coronary artery lesions after implantation and at follow-up of Palmaz-Schatz, GFX, NIR, and CrossFlex stents. Chronic stent recoil was minimal in the Palmaz-Schatz, GFX, and NIR stents; however, there was small, but significant chronic recoil of the CrossFlex stent.

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.

Successful Withdrawal from the Right Coronary Artery of an NIR Stent Dislodged from the Balloon Catheter

A 58‐year‐old patient who underwent right coronary arterial angioplasty with NIR stent placement is described. The stent was dislodged from the balloon catheter and a technique of stent entrapment with two guidewires was successfully performed to remove it from the coronary artery.

Clinical and angiographic results of stenting for long coronary arterial atherosclerotic lesions

A prospective registry of 187 patients who underwent percutaneous coronary angioplasty with attempted long NIR stent delivery was performed. A successful stent delivery was achieved in 93% of cases with a low rate of major cardiovascular events, and 6-month follow-up showed low rates of clinical events, new revascularization procedures, and angiographic restenosis.

Acute results of ablation of coronary in-stent restenoses with eccentric excimer laser catheters

Laser catheters which run eccentrically on a guide wire were developed for maximization of luminal gain by excimer laser angioplasty (ELCA). We investigated the safety and efficacy of ELCA with these new catheters plus PTCA in patients with restenoses or occlusions in coronary stents. ELCA was performed in 57 patients (60 +/- 9 years) with stenoses in 75 stents (35 AVE Micro stents, 26 Palmaz-Schatz stents, 7 NIR stents, 7 other stents). In 44 patients eccentric 1.7 mm catheters and in 13 patients 2.0 mm catheters were used. The success of the intervention was analyzed by intravascular ultrasound (IVUS) in a subgroup of 7 patients treated with five 1.7 mm and two 2.0 mm catheters. The laser catheters could be advanced through the in-stent restenoses in 56 patients. A passage inhibition occurred in one patient with an inadequately expanded stent < 2.0 mm in diameter. ELCA reduced the diameter stenoses from 77 +/- 10% before intervention to 44 +/- 8% after treatment with the 1.7 mm catheter (n = 43) or to 34 +/- 9% after passages with the 2.0 mm catheter (P < 0.001). PTCA further reduced the diameter stenosis to 11 +/- 12% (P < 0.001). The IVUS analysis revealed a smooth ablation profile in all patients. In 4 patients creatine kinase elevations > or = 2 times normal value occurred. There was no evidence of a Q-wave infarction. No dissections were observed within the stents. Outside of the stents there were dissections in 5 vessels, which required the implantation of additional stents. ELCA with eccentric laser catheters for treatment of in-stent restenosis is safe and effective. The incidence of complications is acceptable.