Drug-eluting Stent Failure Research Articles

Predictive Factors for Restenosis after Drug-Eluting Stent Implantation

Background and Objectives：Despite the dramatic reduction in restenosis conferred by drug-eluting stents (DES), restenosis remains a significant problem for real-world patients. Restenosis is a complex phenomenon, and a variety of stent-, drug-, patient- and lesion-related factors have been studied as the determinants of restenosis after DES implantation. Methods and Results：The stent delivery system, the polymer and the drug are integral components of DES, and these are the device-specific factors that can affect restenosis. While the sirolimuseluting Cypher stent appears to provide better outcomes than the paclitaxel-eluting Taxus stent in high-risk patient groups with complex lesions, such differences between the two DES are not apparent in the low-risk groups. Diabetic patients are generally prone to restenosis after percutaneous coronary intervention, but there are conflicting findings regarding the impact of diabetes mellitus on restenosis after DES implantation. The postintervention final lumen area continues to be the most important determinant of restenosis after DES implantation, indicating that a greater stented area contributes to a decreased rate of restenosis even in the DES era. Nonuniform strut distribution and stent fracture also contribute to the development of restenosis after DES implantation. In addition, the risk of restenosis increases linearly according to lesion length, and a “full metal jacket” approach in small vessels is related to a high risk of DES failure. Conclusion：Small vessel disease, diffuse disease and the type of DES are important predictors of restenosis after DES implantation. However, predicting restenosis remains difficult, and this indicates the need for further studies in order to ultimately identify those patients who are at high risk for DES failure. (Korean Circulation J 2007;37:97-102)

Incidence and predictors of recurrent restenosis following implantation of drug‐eluting stents for in‐stent restenosis

We investigated the incidence and predictors of recurrent restenosis after drug-eluting stent (DES) implantation for in-stent restenosis (ISR) in routine clinical practice. Although DESs have been increasingly used for treatment of ISR, little is known about the predictors of DES failure. We determined the incidence of recurrent restenosis and major adverse cardiac events (MACE) in 224 consecutive patients with 239 lesions treated with sirolimus-eluting (n=217 lesions) or paclitaxel-eluting (n=22 lesions) stents for the first episode of ISR. The procedural success rate was 99.2%, and in-hospital complications did not occur in any patient. Follow-up angiography at 6 months was obtained in 73.7% of patients. Angiographic re-restenosis rate was 12.6%, and target lesion revascularization was required in 7.6% of patients. Of the 22 incidents of re-restenosis, 15 were focal (68.2%), 5 were diffuse (22.7%), and 2 were total (9.1%) restenosis. Univariate analysis showed that lesion length, use of paclitaxel-eluting stent, and number of stents per lesion were significant predictors of re-restenosis. In multivariate analysis, however, lesion length and use of paclitaxel-eluting stent were independent predictors of re-restenosis. During the follow-up (mean, 18.3+/-8.1 months), there were 4 deaths (1 cardiac, 3 noncardiac), but no nonfatal myocardial infarctions (MIs). MACE occurred in 18 patients. The cumulative probability of MACE-free survival was 92.9+/-1.8% at 1 year and 90.5+/-2.4% at 2 years. DESs are highly effective for treatment of ISR, with recurrent restenosis related to lesion length and type of DES.

An Intravascular Ultrasound Analysis of the Mechanisms of Restenosis Comparing Drug-Eluting Stents With Brachytherapy

There are treatment failures after de novo drug-eluting stent (DES) implantation and after treatment with DESs or vascular brachytherapy (VBT) of in-stent restenosis (ISR) lesions. We studied 38 patients who presented with DES failure (26 patients after de novo DES implantation and 12 patients after DES treatment of ISR) and 30 patients who presented with VBT failure (all after treatment of ISR). Standard clinical data were collected and volumetric intravascular ultrasound was measured. Patients who presented with DES failures were 58.8 +/- 9.6 years of age and those who presented with VBT failures were 59.8 +/- 8.7 years of age; 60.5% of DES and 58.6% of VBT failures were in men; 31.5% of DES failures and 46.6% of VBT failures occurred in diabetic patients; and times to presentation were 210 +/- 101 days in DES failures and 510 +/- 527 days in VBT failures (p = 0.001). Minimal stent area was significantly larger in VBT than in the 2 DES failure groups (de novo DES implantation and DES treatment of ISR, p <0.0001); this was associated with more neointimal hyperplasia in VBT failures (p <0.0001). After it was normalized to stent length, intimal hyperplasia was diffusely distributed in VBT failures; conversely, DES failures were associated with less intimal hyperplasia and the intimal hyperplasia was mostly focal, with greater accumulation in the proximal and mid segments. In conclusion, VBT failures were caused by significant, recurrent, and diffuse intimal hyperplasia in the setting of adequate stent expansion, whereas DES failures were caused by only modest, but focal, intimal hyperplasia in the setting of DES underexpansion.

Predictors of Restenosis After Placement of Drug-Eluting Stents in One or More Coronary Arteries

Although drug-eluting stents (DESs) have been increasingly used in a wide variety of clinical and anatomic situations, limited data are available regarding the predictors of DES failure in unselected lesions. We investigated the incidence and predictors of restenosis after implantation of DESs in routine clinical practice. A total of 1,795 consecutive patients underwent successful implantation of sirolimus-eluting (1,374 patients, 1,788 lesions) or paclitaxel-eluting (421 patients, 517 lesions) stents. Of the 1,743 eligible patients (2,221 lesions), follow-up angiography at 6 months was obtained for 1,228 patients (70.5%, 1,577 lesions). All data were prospectively recorded and analyzed to predict the occurrence of restenosis, defined as a diameter stenosis of > or =50%. Restenosis was documented in 125 patients with 138 lesions (8.8%), and target lesion revascularization was required in 70 patients with 82 lesions (5.2%). The pattern of restenosis was 85 focal (62%), 29 diffuse (21%), 11 diffuse proliferative (8%), and 13 total (9%). Lesion length, stent length, postintervention minimal lumen diameter, preintervention minimal lumen diameter, reference artery size, complex lesions, and use of a paclitaxel-eluting stent were univariate predictors of restenosis. Multivariate analysis showed that the use of a paclitaxel-eluting stent (odds ratio [OR] 4.37, 95% confidence interval [CI] 2.90 to 6.58, p <0.001), postintervention minimal lumen diameter (OR 0.32, 95% CI 0.20 to 0.50, p <0.001), and lesion length (OR 1.02, 95% CI 1.01 to 1.04, p <0.001) were independent predictors of restenosis. In conclusion, the rate of restenosis after DES implantation in routine clinical practice was similar to the rate reported in clinical trials, confirming the efficacy of DES in routine clinical practice.

Intracoronary brachytherapy following drug-eluting stent failure It's still not time to hang up the spikes!

Drug-eluting stents (DES) have significantly reduced the incidence of restenosis. Although the results obtained with these novel antiproliferative devices are encouraging, recent reports have shown that DES are not completely immune from restenosis. Therefore, the broad use of DES has inevitably led to a major issue: treatment of DES failure. Intracoronary brachytherapy (IBT) represents an important advancement for treatment of in-stent restenosis (ISR) and has led to important pathophysiological insight on the restenotic process. To date, IBT, when properly used, still represents the gold standard for treatment of ISR. However, experience with IBT is for treatment of ISR occurring with bare metal stents (BMS). Whether IBT may be used with the same safety and efficacy profile as an adjunctive treatment for ISR following DES implantation is still unknown. In this article, we report the outcome of a series of patients with DES failure treated with IBT. IBT for treatment of DES failure was shown to be both safe and efficient and, therefore, until ISR exists, IBT still remains an important player in this growing and even more challenging setting.

Intracoronary brachytherapy following drug-eluting stent failure It's still not time to hang up the spikes!

Intracoronary brachytherapy following drug-eluting stent failure It's still not time to hang up the spikes!

Vascular Brachytherapy Boon or Bust?

In the present issue of Circulation , Drs Teirstein and King1 and Waksman and Weinberger2 provide a chronology for the evolution in concept and practice of vascular brachytherapy (VBT). The documentation for durable efficacy of VBT in suppressing recurrent in-stent restenosis (ISR) has been provided by multiple randomized controlled clinical trials. The importance of extending the length of radiated arterial segments well beyond the zone of procedural endoluminal injury has become evident. Similarly, the relative clinical and angiographic safety of VBT (versus conventional therapies for ISR) has been demonstrated, and specific procedural as well as adjunctive pharmacological protocol modifications have evolved. These have included the avoidance of restenting and the prolonged administration of clopidogrel therapy, which have collectively effectively eliminated the previously alarming issue of late thrombosis after VBT. Finally, an effective …

P526 Drug eluting stent failure: a new challenging therapeutic problem

P526 Drug eluting stent failure: a new challenging therapeutic problem