Pattern Of Restenosis Research Articles

Effect of Sirolimus-Eluting Stent in Diabetic Patients With Small Coronary Arteries (A SES-SMART Substudy)

Randomized clinical trials have shown that sirolimus-eluting stents (SESs) decrease restenosis rates compared with bare metal stents (BMSs), but their efficacy among patients who have diabetes mellitus remains to be established. This study investigated the effect of SES implantation in a high-risk population (i.e., patients who had diabetes and small coronary vessel disease). For this purpose, we analyzed outcomes of the subset of patients who had diabetes and were enrolled in the SES-SMART, a randomized trial that compared the results of implantation of SESs and BMSs in small coronary arteries. Twenty-nine patients who had diabetes were originally randomized to receive SESs and 45 patients received BMSs. The use of SESs was associated with approximately 60% decreases in the relative incidence of in-segment angiographic restenosis (63% vs 25%, p = 0.003) and in-segment late loss (0.76 vs 0.28 mm, p <0.002). Angiographic patterns of restenosis were more favorable in the SES group. SES implantation was associated with a 15% absolute decrease in adverse clinical events. In patients who had insulin-dependent diabetes mellitus, SESs showed a high in-segment restenosis rate (40%) that was principally due to persistent restenosis. In conclusion, in diabetics with small coronary arteries, SES implantation significantly reduces the incidence of the 8-month angiographic restenosis rate compared with BMSs.

Recurrence of in-stent restenosis in cardiac allograft vasculopathy following implantation of a sirolimus-eluting stent

Coronary lesions in patients with advanced cardiac allograft vasculopathy (CAV) are frequently treated with percutaneous coronary intervention. Despite high primary success rates, long-term outcome is significantly impaired by a high incidence of restenosis. In nontransplanted patients, the use of drug-eluting stents (DES) significantly decreases the rate of coronary in-stent restenosis. We report a case treated for cardiac allograft coronary in-stent restenosis with a sirolimus-eluting stent presenting with recurrent in-stent restenosis at follow up. However, the pattern of in-stent restenosis changed from diffuse proliferative disease in the bare-metal stent to a focal pattern in the sirolimus-eluting stent concordant with observations in nontransplanted patients. This case highlights the need for further studies addressing the effect of DES for the prevention of restenosis both in de novo as well as in-stent restenotic lesions in patients with CAV.

Effects of mycophenolate mofetil on key pattern of coronary restenosis: a cascade of in vitro and ex vivo models

BackgroundMycophenolate mofetil (MMF), the prodrug of mycophenolic acid (MPA), is a rationally designed immunosuppressive drug. The current study investigates the effect of MMF on key pattern of restenosis in a cascade of in vitro and ex vivo models.MethodsPart I of the study investigated in northern blot and cytoflow studies the effect of MMF (50, 100, 150, 200, 250, and 300 μg/mL) on TNF-α induced expression of intercellular adhesion molecule 1 (ICAM-1) in human coronary endothelial cells (HCAEC) and human coronary medial smooth muscle cells (HCMSMC). Part II of the study applied a human coronary 3D model of leukocyte attack, the 3DLA-model. HCAEC and HCMSMC were cultured on both sides of a polycarbonate filters, mimicking the internal elastic membrane. Leukocyte attack (LA) was carried out by adding human monocytes (MC) on the endothelial side. The effect of MMF (50 μg/mL) on adhesion and chemotaxis (0.5, 1, 2, 3, 4, 6, and 24 h after LA) and the effect on proliferation of co-cultured HCMSMC (24 h after LA) was studied. In part III of the study a porcine coronary organ culture model of restenosis (POC-model) was used. After ex vivo ballooning MMF (50 μg/mL) was added to the cultures for a period of 1, 2, 3, 4, 5, 6, and 7 days. The effect on reactive cell proliferation and neointimal thickening was studied at day 7 and day 28 after ballooning.ResultsExpression of ICAM-1 in northern blot and cytoflow studies was neither clearly inhibited nor stimulated after administration of MMF in the clinical relevant concentration of 50 μg/mL. In the 3DLA-model 50 μg/mL of MMF caused a significant antiproliferative effect (p < 0.001) in co-cultured HCMSMC but had no effect on MC-adhesion and MC-chemotaxis. In the ex vivo POC-model neighter reactive cell proliferation at day 7 nor neointimal hyperplasia at day 28 were significantly inhibited by MMF (50 μg/mL).ConclusionThus, the data demonstrate a significant antiproliferative effect of clinical relevant levels of MMF (50 μg/mL) in the 3DLA-model. The antiproliferative effect was a direct antiproliferative effect that was not triggered via reduced expression of ICAM-1 or via an inhibition of MC-adhesion and chemotaxis. Probably due to technical limitations (as e.g. the missing of perfusion) the antiproliferative effect of MMF (50 μg/mL) could not be reproduced in the coronary organ culture model. A cascade of focused in vitro and ex vivo models may help to gather informations on drug effects before large experimental studies are initiated.

Polymer-based paclitaxel-eluting stent for treatment of chronic total occlusions of native coronaries: Results of a Taxus CTO registry

The purpose of this prospective nonrandomized study was to evaluate both safety and efficacy of the polymer-based paclitaxel-eluting Taxus stent for treatment of chronic total coronary occlusions. Drug-eluting stents have been proven safe and efficacious in suppressing neointimal proliferation when used in simple native de novo coronary lesions. However, there are only limited data on safety and efficacy of these stents for treatment of more difficult lesion subsets, especially chronic total occlusions. Forty-five consecutive symptomatic patients with chronic total coronary occlusions were included in this observational single-arm study. Only patients with successfully crossed occlusions were enrolled. Primary endpoints were binary restenosis and late lumen loss at 6-month angiographic follow-up. Secondary endpoints were MACE at 30-day and 6-month follow-up. The 30-day MACE rate was 0%. At 6 months, the cumulative MACE-free survival was 84.4%. There were no deaths, myocardial infarctions, or stent thrombosis up to 6 months poststenting. At angiographic follow-up, the in-stent restenosis rate was 13.2% (5/38). There was a total of five in-stent restenoses, with three focal and two diffuse restenosis patterns. The in-segment late lumen loss was 0.13 +/- 0.58 mm. The stent edge analyses revealed a late loss of 0.21 +/- 0.66 proximally and a negative late loss of -0.10 +/- 0.67 at the distal edge segment. This study shows safety and indicators of efficacy of implantation of the paclitaxel-eluting Taxus stent for treatment of chronic total coronary occlusions. The quantitative angiographic analysis revealed beneficial results with respect to the efficacy surrogates binary restenosis rate and late loss.

Cutting balloon versus conventional balloon angioplasty for the treatment of in-stent restenosis: Results of the restenosis cutting balloon evaluation trial (RESCUT)

ObjectivesThe aim of this trial was to compare cutting balloon angioplasty (CBA) with conventional balloon angioplasty (i.e., percutaneous transluminal coronary angioplasty [PTCA]) for the treatment of patients with coronary in-stent restenosis (ISR). BackgroundRetrospective studies suggest CBA might be superior to conventional PTCA in the treatment of ISR. MethodsThe Restenosis Cutting Balloon Evaluation Trial (RESCUT) is a multicenter, randomized, prospective European trial including 428 patients with all types of ISR (e.g., focal, multifocal, diffuse, proliferative). ResultsIn both groups, the majority of ISR lesions were shorter than 20 mm. The length of restenotic stents was similar (CBA: 18.6 ± 9.7 mm; PTCA: 18.3 ± 8.7 mm). The number of balloons used to treat ISR was lower in the CBA group: only one balloon was used in 82.3% of CBA cases, compared with 75% of PTCA procedures (p = 0.03). Balloon slippage was less frequent in the CBA group (CBA 6.5%, PTCA 25%; p < 0.01). There was a trend toward a lower need for additional stenting in the CBA group (CBA 3.9%, PTCA 8.0%; p = 0.07). At seven-month angiographic follow-up, the binary restenosis rate was not different between the groups (CBA 29.8%, PTCA 31.4%; p = 0.82), with a similar pattern of recurrent restenosis. Clinical events at seven months were also similar. ConclusionsCutting balloon angioplasty did not reduce recurrent ISR and major adverse cardiac events, as compared with conventional PTCA. However, CBA was associated with some procedural advantages, such as use of fewer balloons, less requirement for additional stenting, and a lower incidence of balloon slippage.

Usefulness of the angiographic pattern of in-stent restenosis in predicting the success of gamma vascular brachytherapy

The prognostic role of the angiographic pattern of in-stent restenosis after gamma vascular brachytherapy was assessed from a pooled data set of 4 clinical trials comprising 295 irradiated patients with matched baseline and follow-up angiograms. The binary angiographic restenosis rate increased with worsening in-stent restenosis patterns; however, target lesion revascularization and major adverse cardiac event rates increased for focal, diffuse, and proliferative patterns of in-stent restenosis but not for total occlusions.

May 13, 2003

HomeCirculationVol. 107, No. 18May 13, 2003 Free AccessAnnouncementPDF/EPUBAboutView PDFView EPUBSections ToolsAdd to favoritesDownload citationsTrack citationsPermissions ShareShare onFacebookTwitterLinked InMendeleyReddit Jump toFree AccessAnnouncementPDF/EPUBMay 13, 2003 James T. Willerson, MD James T. WillersonJames T. Willerson Search for more papers by this author Originally published13 May 2003https://doi.org/10.1161/circ.107.18.2283Circulation. 2003;107:2283Circulation’s Newest Section Mini-Review: Expert OpinionsDr Dean Kereiakes is the Section Editor for Circulation’s newest section, Mini-Reviews: Expert Opinions. Expert opinions and advice will be solicited from internationally recognized thought-leaders for topics in cardiovascular medicine that are of interest to the cardiovascular clinician. In addition, health-care policy and patient care issues will be examined attempting to improve clinical care and resource utilization. Mini-Reviews: Expert Opinions will provide timely, useful advice on the recognition and management of important cardiovascular problems and will expand the clinically relevant format of Circulation. The new section will be available in print and via a radio button on the home page of CirculationOnline in January 2003.Circulation’s Ongoing New Features: Clinician Update and The Cardiology Patient PageDr Elliott Antman is Section Editor for two new sections that were introduced in the Online version of Circulation in May 2001. The sections are available as a collection through radio buttons on the home page of Circulation Online, and now the Clinician Update is also published in the print journal. We are pleased to offer the new sections as a review for the clinician and as a resource for the patient.Rapid Track for Review and PublicationThe Rapid Track category of manuscript is designed to provide expedited review within 7 working days and, if accepted, rapid publication of manuscripts reporting the results of important clinical trials and major basic science discoveries. Accepted manuscripts are published online within 7 to 10 working days and within 4 to 5 weeks in the print journal after return of the corrected proofs. If an author believes his/her work meets the criteria for the Rapid Track consideration as stated in our Instructions to Authors, the author should request Rapid Track consideration in the submission letter that accompanies the manuscript.Rapid Access PublicationAll original manuscripts accepted for publication in Circulation are now published Online in our Rapid Access Publication Section one week after proofs are returned to Lippincott Williams & Wilkins and are in print in five weeks. The Online section is available via a radio button on Circulation’s home page.Cardiovascular NewsCardiology Patient PageBeta-Adrenergic BlockersWilliam H. Frishman, MD (Circulation. 2003;107:e117-e119.)Images in Cardiovascular MedicineTako-Tsubo –Like Transient Left Ventricular DysfunctionJohn P.Girod, DO; Adrian W.Messerli, MD; Frank Zidar,MD; W.H. WilsonTang,MD; SorinJ. Brener,MD(Circulation. 2003;107:e120-e121.)Correspondence(Circulation. 2003;107:e122-e128.) Previous Back to top Next FiguresReferencesRelatedDetailsCited By Li Y, Yu M, Li W, Lu Z, Wei M and Zhang J (2018) Third generation dual-source CT enables accurate diagnosis of coronary restenosis in all size stents with low radiation dose and preserved image quality, European Radiology, 10.1007/s00330-017-5256-3, 28:6, (2647-2654), Online publication date: 1-Jun-2018. Yu M, Lu Z, Li W, Wei M, Yan J and Zhang J (2018) Coronary plaque characteristics on baseline CT predict the need for late revascularization in symptomatic patients after percutaneous intervention, European Radiology, 10.1007/s00330-018-5320-7, 28:8, (3441-3453), Online publication date: 1-Aug-2018. Hanawa T (2017) Metal–Polymer Composite Biomaterials Concise Encyclopedia of Biomedical Polymers and Polymeric Biomaterials, 10.1081/E-EBPPC-120052255, (877-899), Online publication date: 11-Sep-2017. Li M, Zhang J, Zhang Q, Pan J, Lu Z and Wei M (2014) Coronary stent occlusion: reverse attenuation gradient sign observed at computed tomography angiography improves diagnostic performance, European Radiology, 10.1007/s00330-014-3429-x, 25:2, (568-574), Online publication date: 1-Feb-2015. Pan J, Lu Z, Zhang J, Li M and Wei M (2012) Angiographic patterns of in-stent restenosis classified by computed tomography in patients with drug-eluting stents: correlation with invasive coronary angiography, European Radiology, 10.1007/s00330-012-2559-2, 23:1, (101-107), Online publication date: 1-Jan-2013. Zhang J, Li M, Lu Z, Hang J, Pan J and Sun L (2011) In vivo evaluation of stent patency by 64-slice multidetector CT coronary angiography: shall we do it or not?, The International Journal of Cardiovascular Imaging, 10.1007/s10554-011-9842-1, 28:3, (651-658), Online publication date: 1-Mar-2012. Hanawa T (2009) Materials for metallic stents, Journal of Artificial Organs, 10.1007/s10047-008-0456-x, 12:2, (73-79), Online publication date: 1-Jun-2009. Alvarez W and Kapur N (2016) Drug Eluting Stent Technology, Journal of Pharmacy Practice, 10.1177/0897190005282359, 18:6, (461-478), Online publication date: 1-Dec-2005. Hanawa T (2015) Metal–Polymer Composite Biomaterials Encyclopedia of Biomedical Polymers and Polymeric Biomaterials, 10.1081/E-EBPP-120052255, (4551-4573) May 13, 2003Vol 107, Issue 18 Advertisement Article InformationMetrics https://doi.org/10.1161/circ.107.18.2283 Originally publishedMay 13, 2003 PDF download Advertisement

Effect of Homocysteine-Lowering therapy on restenosis after percutaneous coronary intervention for narrowings in small coronary arteries

umenting all balloon infl ations on fi lm. To that end, investigators were provided a protocol for acquiring angiograms at the initiation of the trial to ensure optimal angiographic quality. Although compliance with the protocol and fi lm quality were generally excellent, deviations from the protocol were not quantifi ed, and some device use may not have been captured on fi lm. Second, the high frequency of geographic miss in our study, based on our defi nition, may limit our ability to detect differences between the groups because of the small sample of patients without geographic miss. Finally, intravascular ultrasound was not performed systematically at follow-up, but would have provided valuable insight into the mechanism of edge recurrence. In INHIBIT, the presence and length of geographic miss were not associated with increases in overall restenosis for either radiated or placebo patients. The treatment effect of P-32 was maintained despite the presence of geographic miss, and there was no identifiable detrimental interaction between radiation and geographic miss. There is no angiographic evidence that P-32 has a proliferative effect as the dose decreases. 1. Mehran R, Dangas G, Abizaid AS, Mintz GS, Lansky AJ, Satler LF, Pichard AD, Kent KM, Stone GW, Leon MB. Angiographic patterns of in-stent restenosis: classifi cation and implications for long-term outcome. Circulation 1999;100: 1872–1878.

Drug Delivery Systems for Stents

Drug-eluting stents have emerged as the single most promising therapeutic approach to prevent restenosis, a formidable limitation of percutaneous coronary revascularization. Stent-based drug delivery engenders a number of critical chemical, drug, polymer, and mechanical engineering challenges that must be addressed to develop an effective restenosis therapy. The challenges of stent-based delivery using potent antiproliferative compounds and polymeric surface coatings are easily apparent in the design and development of first-generation drug-eluting stents. Adverse clinical outcomes with potent cytotoxic stent-based therapies, such as dactinomycin and a high dose, slow release paclitaxel derivative, represents the dark-side of the drug-eluting stent, with early aggressive patterns of restenosis, increased stent thrombosis, and aneurysm formation. These adverse clinical outcomes with drug-eluting stents highlight the importance of understanding the interactions of the drug and polymer, as well as the role of the residual polymer coating in determining long-term clinical results.The ultimate fate, or the ‘healed arterial response’ to residual polymeric material, remains a controversial issue due to the limited availability of long-term clinical follow-up data for most drug-eluting stents.

Changing pattern of in-stent restenosis after intracoronary beta-irradiation: downsizing the lesion

Changing pattern of in-stent restenosis after intracoronary beta-irradiation: downsizing the lesion

Preprocedural levels of acute phase reactants predict an aggressive clinical pattern of restenosis following coronary angioplasty

Preprocedural levels of acute phase reactants predict an aggressive clinical pattern of restenosis following coronary angioplasty

Patterns of in-stent restenosis after placement of NIR gold-coated stents in unselected patients.

The aim of this study was to assess the incidence and angiographic patterns of in-stent restenosis 6 months after the implantation of NIR gold-coated stents in an unselected patient population. One hundred and sixteen consecutive patients were treated with the implantation of 149 NIR gold-coated stents. The majority of the patients (52%) had unstable angina or acute myocardial infarction. The baseline lesion morphology was complex in 78% of cases; the mean lesion length was 18 +/- 5 mm. The procedural success rate was 97%. Subacute stent thrombosis occurred in three patients (2.6%). During the 6-month follow-up, there were 2 deaths and 22 subjects (19.5%) underwent target vessel revascularization. The 6-month event-free survival was 60%. The angiographic restenosis rate was 32%. In 83% of the cases, the morphology of the restenosis was proliferative; in the remaining 17%, it presented as total occlusion. In conclusion, the restenosis rate after NIR gold-coated stent implantation in high-risk patients is similar to that reported using other stent designs. However, restenosis was always diffuse, involving the overall stent length and extending beyond the margins, thus indicating a greater proliferative neointimal response to this device.

The pattern of restenosis and vascular remodelling after cold-end radioactive stent implantation.

Edge restenosis is a major problem after radioactive stenting. The cold-end stent has a radioactive mid-segment (15.9 mm) and non-radioactive proximal and distal 5.7 mm segments. Conceptually this may negate the impact of negative vascular remodelling at the edge of the radiation. ECG-gated intravascular ultrasound with three-dimensional reconstruction was performed post-stent implantation and at the 6-month follow-up to assess restenosis within the margins of the stent and at the stent edges in 16 patients. Angiographic restenosis was witnessed in four patients, all in the proximal in-stent position. By intravascular ultrasound in-stent neointimal hyperplasia, with a >50% stented cross-sectional area, was seen in eight patients. This was witnessed proximally (n=2), distally (n=2) and in both segments (n=4). Echolucent tissue, dubbed the 'black hole' was seen as a significant component of neointimal hyperplasia in six out of the eight cases of restenosis. Neointimal hyperplasia was inhibited in the area of radiation: Delta neointimal hyperplasia=3.72 mm3 (8.6%); in-stent at the edges of radiation proximally and distally Delta neointimal hyperplasia was 7.9 mm3 (19.0%) and 11.4 mm3 (25.6%), respectively (P=0.017). At the stent edges there was no significant change in lumen volume. Cold-end stenting results in increased neointimal hyperplasia in in-stent non-radioactive segments.

Relation between the insertion/deletion polymorphism of the angiotensin I converting enzyme gene and restenosis after coronary stenting.

Observations with intravascular ultrasound demonstrated that neointimal hyperplasia is the predominant factor responsible for in-stent restenosis. Experimental data suggest that angiotensin I converting enzyme (ACE) plays a role in the thickening of neointima after balloon denudation. Insertion/deletion (I/D) polymorphism of the ACE gene is significantly associated with plasma level of ACE and subjects with D/D genotype have significantly higher plasma levels of ACE than normal. To investigate whether this polymorphism influences the risk of restenosis after coronary stenting. We genotyped 158 patients who had undergone single-vessel coronary stenting for the ACE I/D polymorphism. Of the 158 patients, 56 (35%) had the D/D genotype, 71 (45%) had the I/D genotype and 31 (20%) had the I/I genotype. Prevalences of genotypes were compatible with Hardy-Weinberg equilibrium and distributions of ACE genotype among patients and 132 healthy controls from the same geographic area did not differ. At follow-up (after a median duration of 5.4 months), overall rates of angiographic restenosis and of revascularization of target lesion (RTL) were 32.3 and 22.8%, respectively. Of 51 patients with angiographic restenosis, 31 (60.8%) had focal and 20 (39.2%) had diffuse patterns of restenosis. Diffuse in-stent restenosis was significantly more prevalent among patients with D/D genotype (P = 0.016). Multiple stepwise logistic regression analysis identified ACE I/D polymorphism as the independent predictor of angiographic restenosis and RTL. Relative risk of angiographic restenosis was 6.29 [95% confidence interval (CI), 1.80-22.05, P = 0.0004] for D/D genotype and 3.88 (95% CI 1.11-13.12, P = 0.029) for I/D genotype, whereas relative risk of RTL was 7.44 (95% CI 1.60-34.58, P = 0.01) for D/D genotype and 3.88 (95% CI 0.083-18.15, P = 0.085) for I/D genotype. The ACE I/D polymorphism is significantly associated with risk of angiographic and clinical restenosis after coronary stenting. Angiographic pattern of restenosis is also significantly associated with I/D polymorphism, diffuse type being more prevalent among subjects with D/D genotype.

A prospective evaluation of angiography-guided coronary stent implantation with high versus very high balloon inflation pressure

Background High inflation pressure (HP) after coronary stent deployment has become a standard approach because it has been associated with a decreased subacute stent thrombosis (SAT) rate. However, the impact of HP on long-term outcomes is still unclear. We compared the long-term results of a strategy of increasing HP (≥12 atm) until the achievement of angiographic success (<20% residual stenosis) with a prespecified very high inflation pressure (VHP) strategy of 20 atm without intermediate inflations. Methods and Results We conducted a parallel-group, nonrandomized study to evaluate the short- and long-term results in 136 consecutive eligible patients who underwent successful single Palmaz-Schatz stent implantation in vessels ≥3 mm. Major adverse cardiac events (MACE), that is, death, myocardial infarction, and target lesion revascularization (TLR), were monitored for a minimum of 6 months. No significant differences were observed between the two strategies in terms of final minimal lumen diameter (HP, 3.0 ± 0.5 vs VHP, 3.1 ± 0.5 mm) and acute gain (HP, 2.1 ± 0.7 vs VHP, 2.2 ± 0.6). The overall rate of subacute stent thrombosis was 0.7%. During a 405 ± 148-day follow-up, 21 (28.8%) patients in the VHP group and 6 (9.5%) in the HP group (P =.005) had MACE, with a TLR rate of 27.4% versus 7.9% (P =.009), respectively. By multivariate analysis, the use of VHP increased the odds of long-term MACE by a factor of 3.48 (P =.009). Among patients undergoing TLR, those treated with VHP had a greater lumen loss (HP, 1.83 ± 0.57 vs VHP, 2.15 ± 0.36 mm, P =.02) and a more frequent pattern of diffuse restenosis (71% vs 16%, P =.06). Conclusions In our study, the two strategies had similar acute and short-term results, but VHP was associated with a poorer long-term outcome. These data provide a rationale for a less aggressive strategy for stent deployment by optimizing rather than attempting to maximize inflation pressure and stent expansion. (Am Heart J 2000;140:804-12.)

Coronary stent implantation changes 3-D vessel geometry and 3-D shear stress distribution

Mechanisms of in-stent restenosis are not fully understood. Shear stress is known to play a role in plaque and thrombus formation and is sensitive to changes in regional vessel geometry. Hence, we evaluated the regional changes in 3-D geometry and shear stress induced by stent placement in coronary arteries of pigs. Methods. 3-D reconstruction was performed, applying a combined angiographic and IVUS technique (ANGUS), from seven Wallstents (diameter 3.5 ( n=3) and 5 mm ( n=4)), which were implanted in seven coronary arteries of five pigs. This 3-D geometry was used to calculate locally the curvature, while the shear stress distribution was obtained by computational fluid dynamics. Local changes in shear stress were obtained at the entrance and exit of the stent for baseline (0.65±0.22 ml/s) and hyperemic flow (2.60±0.86 ml/s) conditions. Results. After stent implantation, the curvature increased by 121% at the entrance and by 100% at the exit of the stent, resulting in local changes in shear stress. In general, at the entrance of the stent local maxima in shear stress were generated, while at the exit both local maxima and minima in shear stress were observed ( p<0.05). Additionally, the shear stress at the entrance and exit of the stent were correlated with the local curvature ( r: 0.30–0.84). Conclusion. Stent implantation changes 3-D vessel geometry in such a way that regions with decreased and increased shear stress occur close to the stent edges. These changes might be related to the asymmetric patterns of in-stent restenosis.

In-stent restenosis: long-term outcome and predictors of subsequent target lesion revascularization after repeat balloon angioplasty

OBJECTIVESWe sought to evaluate the long-term clinical outcome of patients undergoing successful balloon angioplasty for in-stent restenosis, and to determine correlates of the need for subsequent target lesion revascularization (TLR).BACKGROUNDIn-stent restenosis can be safely treated by repeat percutaneous intervention. Reported subsequent TLR rates have varied from 20% to 80% and seem related to the type of restenotic lesion.METHODSThe study population comprised 234 patients with follow-up data who were successfully treated with repeat balloon angioplasty for in-stent restenosis in 257 lesions between May 1995 and January 1998 at our institution.RESULTSClinical follow-up was available at 459 (286 to 693) days after the repeat procedure. Event-free survival was 78.5% and 74.6% at 12 and 24 months, respectively. Recurrent events occurred in 58 patients (24.8%), including 6 deaths (2.6%), 4 myocardial infarction (1.7%) and repeat target vessel revascularization in 50 patients (21.4%). Independent predictors of repeat TLR were time to in-stent restenosis <90 days (Hazard ratio 4.67, p < 0.001), minimal luminal diameter after repeat procedure (Hazard ratio 0.38, p = 0.034) and the angiographic pattern of in-stent restenosis (Hazard ratio 1.65, p = 0.036).CONCLUSIONSBalloon angioplasty is an effective means of treating in-stent restenosis. The long-term results are acceptable particularly for focal restenotic lesions. Further restenosis is more common in patients with early initial recurrence, more proliferative lesions and a poorer angiographic result from repeat angioplasty.

Angiographic patterns of in-stent restenosis and implications on subsequent revascularization.

Stent implantation has become the mainstay of percutaneous revascularization for most coronary lesions; in-stent restenosis (ISR) can occur in 6%-40% of stent procedures and the subsequent response to repeat intervention can possibly be predicted by the angiographic patterns of ISR. This study evaluated the incidence and predictors of angiographic patterns of ISR and its impact on subsequent target lesion revascularization (TLR) in 100 consecutive patients having Palmaz-Schatz ISR undergoing intervention. Diffuse ISR (>/=10 mm) was observed in 78% and focal ISR (>10 mm) in 22%. Diffuse vs. focal ISR occurred earlier after stent implantation and was more common in diabetics. Angiographic predictors of diffuse ISR were stent implantation for a restenotic lesion, long lesions, smaller vessel, stenting without debulking, and high-pressure balloon inflation (>16 atm). TLR after repeat intervention was 46% for diffuse and 14% for focal ISR (P < 0.02). Rotational atherectomy resulted in lower TLR (31%) vs. PTCA or restent (64%) in diffuse ISR (P < 0.004). Therefore, diffuse ISR is more common than focal ISR, usually occurs in the setting of aggressive intimal hyperplasia, and can be predicted by clinical and angiographic variables. Also, diffuse intimal hyperplasia within a stent responds poorly to PTCA and may benefit from a more aggressive debulking strategy such as rotational atherectomy. Cathet. Cardiovasc. Intervent. 49:23-29, 2000.

Angiographic patterns of in-stent restenosis: classification and implications for long-term outcome.

The angiographic presentation of in-stent restenosis (ISR) may convey prognostic information on subsequent target vessel revascularizations (TLR). We developed an angiographic classification of ISR according to the geographic distribution of intimal hyperplasia in reference to the implanted stent. Pattern I includes focal (< or =10 mm in length) lesions, pattern II is ISR>10 mm within the stent, pattern III includes ISR>10 mm extending outside the stent, and pattern IV is totally occluded ISR. We classified a total of 288 ISR lesions in 245 patients and verified the angiographic accuracy of the classification by intravascular ultrasound. Pattern I was found in 42% of patients, pattern II in 21%, pattern III in 30%, and pattern IV in 7%. Previously recurrent ISR was more frequent with increasing grades of classification (9%, 20%, 34%, and 50% for classes I to IV, respectively; P=0.0001), as was diabetes (28%, 32%, 39%, and 48% in classes I to IV, respectively; P<0.01). Angioplasty and stenting were used predominantly in classes I and II, whereas classes III and IV were treated with atheroablation. Final diameter stenosis ranged between 21% and 28% (P=NS among ISR patterns). TLR increased with increasing ISR class; it was 19%, 35%, 50%, and 83% in classes I to IV, respectively (P<0.001). Multivariate analysis showed that diabetes (odds ratio, 2.8), previously recurrent ISR (odds ratio, 2. 7), and ISR class (odds ratio, 1.7) were independent predictors of TLR. The introduced angiographic classification is prognostically important, and it may be used for appropriate and early patient triage for clinical and investigational purposes.

Clinical Pattern and Long-term Behavior of Significant Angiographic Restenosis After Coronary Stenting

Clinical Pattern and Long-term Behavior of Significant Angiographic Restenosis After Coronary Stenting