Another view of personalized medicine: optimizing stent selection on the basis of predicted benefit in percutaneous coronary intervention

Drug-eluting stents (DES) decrease the risk of restenosis compared to bare metal stents (BMS) for percutaneous coronary intervention (PCI). However, their use requires patients to take prolonged dual antiplatelet therapy that increases bleeding risk and without which, patients have an increased risk of developing stent thrombosis. In light of these competing risks, understanding which patients derive the greatest benefit of DES compared to BMS is essential for guiding therapy. We review recent efforts to predict the magnitude of the restenosis benefit of DES compared to BMS for individual patients. Understanding and predicting the likelihood of benefit for individual patients is essential to rational decision making with regard to the type of stent to use during PCI and will serve to increase the value of the health care that clinicians deliver.     

Percutaneous intervention on the saphenous vein bypass grafts—Long‐term outcomes

Background/Objective : In this era of drug eluting stents (DES), the long‐term outcome of percutaneous intervention (PCI) on saphenous venous grafts (SVG) is unknown. The objective of the study was to compare the long‐term outcomes of DES versus bare metal stent (BMS) in this population and to determine the predictors of outcomes. Methods : We reviewed the medical records of all patients who had PCI performed during January 2003 to February 2005 to obtain data cardiac risk factors, medications at discharge, angiographic details and outcomes. Results : One hundred and nine patient had PCI to SVG; of these, 37 patients received DES and the remaining had BMS. Over a mean follow‐up of 33 months, the PCI using DES was associated with 30% restenosis, 35% target vessel revascularization (TVR) and major adverse cardiac event (MACE) rate of 46% versus 35% restenosis, 38% TVR and 50% MACE rate with BMS. There was no significant difference in long‐term outcome with DES as compared to BMS. Conclusion : There was no difference in the long‐term outcomes of PCI on SVG irrespective of the type of stent used. © 2008 Wiley‐Liss, Inc.     

Duration of dual anti‐platelet therapy following drug eluting stents

• This meta‐analysis suggests that abbreviated DAPT (<6 months) could be considered in patients undergoing PCI with current generation drug eluting stents (DES).
• Extended DAPT strategy (>1 year) may be appropriate in those patients in whom prevention of stent and non‐stent‐related coronary events are likely to offset the bleeding complications.
• Additional randomized trials are needed to evaluate the optimum duration of DAPT in patients with the latest generation DES and current antiplatelet drugs.

     

Rotational atherectomy for fibro‐calcific coronary artery disease in drug eluting stent era: Procedural outcomes and angiographic follow‐up results

Objectives: The aim of this study was to examine the binary re‐stenosis rates, procedural success, and in hospital outcomes following treatment of fibro‐calcified coronary lesion with rotational atherectomy in drug eluting stent era. Background: Binary restenosis rates have remained high with the use of bare metal stents following rotational atherectomy in calcified lesions. There is limited data available following rotational atherectomy in drug eluting stent era. Methods: We evaluated the procedural and angiographic outcomes following a consecutive series of 516 procedures treated with rotational atherectomy followed by stenting. We compared the results between Rota + Drug eluting stent (DES) and Rota + bare metal stent (BMS) groups. Results: Procedural success was achieved in 97.1% of the lesions with overall low in hospital adverse events (death in 1.1%, Q MI in 1.3%, Non Q MI in 5.3%, and urgent repeat PCI in 0.4%). There was significant reduction in the binary restenosis rates following Rota + DES use as compared to Rota + BMS use (11% vs. 28.1%, P < 0.001; OR = 3.17, 95% CI: 1.76–5.93) and similar reduction was seen in the target lesion revascularization (10.6% vs. 25%, P = 0.001; OR = 2.81, 95% CI: 1.53–5.14). We have identified ostial lesions, chronic total occlusion lesions, and use of bare metal stents as independent predictors of restenosis in this group of patients. Conclusions: Rotational atherectomy can be performed with high success rates and low complications, and rotational atherectomy followed by drug eluting stent implantation significantly reduces binary restenosis rates in fibrocalcific lesions as compared to rotational atherectomy and bare metal stents. © 2010 Wiley‐Liss, Inc.     

Kissing drug-eluting balloons for the treatment of unprotected distal left main bifurcation drug-eluting stent restenosis

The advent of drug-eluting stents (DES) associated with improvements in interventional techniques, encouraged the use of percutaneous coronary intervention (PCI) for unprotected left main (ULM) stenosis because of the lower need of repeat revascularization compared to the bare-metal stents (BMS). Nevertheless, ULM DES in-stent restenosis (ISR) continues to occur. The choice of treatment strategy (medical treatment, repeated PCI, or coronary artery bypass graft) for ULM DES-ISR depends primarily on several clinical and angiographic factors, making optimal patient selection crucial in the appropriate treatment of ULM-ISR lesions and achievement of favorable long-term outcomes. We describe in this report a successful modern approach to manage a distal ULM DES-ISR following a 2-stent strategy, consisting in the kissing inflation of two DEBs in both branches of the bifurcation.     

Benefits of drug eluting stents versus bare metal stents in ST-elevation myocardial infarction: a contemporary review

The efficacy of drug-eluting stents (DES) in reducing the rates of in-stent restenosis after percutaneous coronary intervention (PCI) compared to bare metal stents (BMS) in stable coronary artery disease has been well demonstrated. Thus, the Food and Drug Administration has approved the utilization of DES for stable coronary disease. However, there is still much debate surrounding the implantation of DES for patients with ST-segment elevation myocardial infarction (STEMI) given safety concerns about the possibility of increased rates of stent thrombosis with DES. The review of the current body of evidence comparing DES with BMS is consistent with results from previous trials in stable coronary disease and reveals lower rates of revascularization with DES in STEMI patients. The ultimate decision regarding the appropriate stent during PCI needs to be individualized as patients' compliance with dual antiplatelet therapy is critical. The data suggest that PCI with DES in STEMI patients who adhere to long-term dual antiplatelet therapy is safe and effective. Randomized trials with longer-term follow-up are necessary to better elucidate the safety and efficacy of DES versus BMS in patients with STEMI.     

Drug-eluting stent-supported percutaneous coronary intervention for chronic total coronary occlusion.

OBJECTIVES: This study sought to determine the clinical and angiographic outcomes after drug-eluting stent (DES)-supported percutaneous coronary intervention (PCI) for chronic total coronary occlusion (CTO). BACKGROUND: There are few data about the efficacy of DES-supported PCI for CTO. METHODS: All consecutive patients who had a sirolimus-eluting stent or a paclitaxel-eluting stent implanted for CTO from December 2003 to December 2004 were analyzed. Clinical and angiographic outcomes of patients treated with DES were compared with a case-matched control group of patients treated with bare metal stents (BMS) in the 12 months before the routine use of DES. RESULTS: Successful DES-supported PCI was performed in 92 patients and 104 CTO. The case-matched control group consisted of 26 patients and 27 CTO successfully treated with BMS. There were no differences between groups in baseline clinical and angiographic characteristics. Stent length in the DES group was higher as compared with that of BMS group (51+/-28 mm vs. 40+/-19 mm, P=0.073). The 6-month major adverse cardiac event (MACE) rate was lower in the DES group as compared with that of BMS group (9.8% vs. 23%, P=0.072). The angiographic follow-rate was 80% in the DES group and 81% in the BMS group. The 6-month restenosis rate was 19% in the DES group and 45% in the BMS group (P<0.001). By multivariate analysis, it was found that in the DES group, the only predictors of restenosis were stented segment length (OR 1.031, 95% CI 1.01-1.06, P=0.009) and a target vessel reference diameter<2.5 mm (OR 6.48, 95% CI 1.51-27.83, P=0.012), while the only predictor of MACE was stent length (OR 1.04, 95% CI 1.01-1.08, P=0.006). CONCLUSIONS: DES implantation for CTO decreases the risk of mid-term restenosis and MACE. Small vessels and diffuse disease requiring the implantation of multiple stents and very long stents for full coverage of the target lesion are still associated with a relatively high risk of restenosis.     

The risks and benefits of drug-eluting stents in the setting of STEMI

Primary percutaneous coronary intervention (PCI) represents the treatment of choice in patients with ST-segment elevation myocardial infarction (STEMI). In randomized trials excluding STEMI patients, using drug-eluting stents (DES) significantly reduced angiographic restenosis and target vessel revascularization compared with bare metal stents (BMS); however, concerns exist regarding an increased follow-up incidence of stent thrombosis after DES implantation. This complication, which is associated with higher mortality and morbidity rates, may be more frequent among STEMI patients receiving DES versus BMS. Various registries, randomized trials, and two recent meta-analyses on patients undergoing primary PCI have shown that using DES is safe and is associated with significantly reduced rates of restenosis and repeat intervention without an increased risk of myocardial infarction or stent thrombosis at intermediate-term follow-up. However, large trials with hard clinical end points and longer follow-up are needed before routine DES use can be recommended in patients undergoing primary PCI.     

Safety and Effectiveness of Firebird Sirolimus-Eluting Stent in Patients With Multi-Vessel Coronary Artery Disease

Objective:This study sought to evaluate the long-term safety and efficacy of the Firebird sirolimus-eluting stent in patients with multi-vessel coronary artery disease.The main limitation of percutaneous coronary intervention(PCI)with bare metal stents(BMS)was the increased incidence of instent restenosis.Recently,DES are frequently implanted in patients with off-label indications such as multi-vessel coronary artery disease.However,the long-term safety and effectiveness of DES among patients with multi-vessel coronary artery disease are not well understood.Methods:From January to December 2006,a total of 392 patients with multi-vessel coronary artery disease,exclusively treated with Firedird stents at 12 centers from China,were enrolled in this prospective,multicenter registry.They were followed up clinically at 6,12,18 and 24 months after the procedure.Results:A core laboratory analyzed quantitative coronary angiography data immediately after stenting and at 6-month follow-up.Acute angiographic success was 100%.Angiographic restenosis rate was 2.80% at the sixth month.The percentage of acute major adverse cardiac events(MACE)was 4.86%,4.37% and 6.91%,and the percentage of secondary cardiac events was 5.62%,5.88% and 6.39% at 12,18 and 24 months,respectively.The incidence of death,myocardial infarction,or stent thrombosis during 24 month was 3.84%(15 of 392),1.02%(4 of 392)or 2.05%(8 of 392).Conclusion:This study indicates that Firebird sirolimus-eluting stent is safe and effective for patients with multi-vessel coronary artery disease.     

Use of drug-eluting stents as a function of predicted benefit: clinical and economic implications of current practice

BACKGROUND Benefits of drug-eluting stents (DES) in percutaneous coronary intervention (PCI) are greatest in those at the highest risk of target-vessel revascularization (TVR). Drug-eluting stents cost more than bare-metal stents (BMS) and necessitate prolonged dual antiplatelet therapy (DAPT), which increases costs, bleeding risk, and risk of complications if DAPT is prematurely discontinued. Our objective was to assess whether DES are preferentially used in patients with higher predicted TVR risk and to estimate if lower use of DES in low-TVR-risk patients would be more cost-effective than the existing DES use pattern. METHODS We analyzed more than 1.5 million PCI procedures in the National Cardiovascular Data Registry (NCDR) CathPCI registry from 2004 through 2010 and estimated 1-year TVR risk with BMS using a validated model. We examined the association between TVR risk and DES use and the cost-effectiveness of lower DES use in low-TVR-risk patients (50% less DES use among patients with <10% TVR risk) compared with existing DES use. RESULTS There was marked variation in physicians' use of DES (range 2%-100%). Use of DES was high across all predicted TVR risk categories (73.9% in TVR risk <10%; 78.0% in TVR risk 10%-20%; and 83.2% in TVR risk >20%), with a modest relationship between TVR risk and DES use (relative risk, 1.005 per 1% increase in TVR risk [95% CI, 1.005-1.006]). Reducing DES use by 50% in low-TVR-risk patients was projected to lower US health care costs by $205 million per year while increasing the overall TVR event rate by 0.5% (95% CI, 0.49%-0.51%) in absolute terms. CONCLUSIONS Use of DES in the United States varies widely among physicians, with only a modest correlation to patients' risk of restenosis. Less DES use among patients with low risk of restenosis has the potential for significant cost savings for the US health care system while minimally increasing restenosis events.     

Outcome of patients treated by a novel thin‐strut cobalt‐chromium stent in the drug‐eluting stent era: Results of the SKICE (Skylor in real world practice) registry

Objectives : To investigate the outcome of patients undergoing percutaneous coronary interventions (PCI) with implantation of a new thin‐strut cobalt‐chromium bare‐metal‐stent (BMS) in the drug‐eluting‐stent (DES) era. Background : Despite the contemporary penetration of DES in the clinical practice, a relevant percentage of patients are still treated by BMS. Data on clinical outcome of novel BMSs are lacking. Methods : This is a single‐centre‐registry enrolling patients treated by Skylor? stent implantation. During the study, the criteria for BMS selection adopted at our institution (“internal” criteria) were as follows: (1) limited compliance to prolonged double antiplatelet therapy, (2) ST‐elevation myocardial infarction (STEMI) or saphenous vein grafts (SVG) interventions, and (3) in the absence of these conditions, noncomplex (no bifurcations, no chronic total occlusions) lesions considered at low restenosis risk on the basis of arbitrary angiographic criteria (short lesions, large vessels). Primary and secondary end‐points were respectively major adverse cardiovascular events (MACE) and target vessel failure (TVF) up to 9‐month. Results: A total of 150 patients were treated with Skylor? stent on 169 lesions. At 9‐month follow‐up, MACE occurred in 12 patients (8.0%) and TVF in 21 lesions (12.4%). By multivariable analysis, the predictors of MACE were Euroscore≥9 and ejection fraction < 30% while the predictors of TVF were the absence of the angiographic criteria of low restenosis risk and ejection fraction < 30%. Conclusions: In the DES era, the use of a last‐generation BMS in patients with limited compliance to double antiplatelet therapy, STEMI or SVG interventions, and noncomplex angiographic lesions may be associated with acceptable clinical outcome. © 2009 Wiley‐Liss, Inc.     

Proximal coronary artery intervention: Stent thrombosis,restenosis and death

Background

Percutaneous coronary intervention (PCI) of lesions in the proximal left anterior descending coronary artery (LAD) may confer a worse prognosis compared with the proximal right coronary artery (RCA) and left circumflex coronary artery (LCX).

Methods

From May 2005, to May 2011 we identified all PCIs for proximal, one-vessel coronary artery disease in the Swedish Coronary Angiography and Angioplasty Registry (SCAAR). We evaluated restenosis, stent thrombosis (ST) and mortality in the LAD as compared to the RCA and LCX according to stent type, bare metal (BMS) or drug-eluting stents (DES).

Results

7840 single vessel proximal PCI procedures were identified. Mean follow-up time was 792 days. No differences in restenosis or ST were seen between the LAD and the RCA. The frequency of restenosis and ST was higher in the proximal LAD compared to the proximal LCX (restenosis: hazard ratio (HR) 2.28, confidence interval (CI) 1.56–3.34 p < 0.001; ST: HR 2.32, CI 1.11–4.85 p = 0.024). We found no difference in mortality related to coronary artery. In the proximal LAD, DES implantation was associated with a lower restenosis rate (HR 0.39, CI 0.27–0.55 p < 0.001) and mortality (HR 0.58, CI 0.41–0.82 p = 0.002) compared with BMS. In the proximal RCA and LCX, DES use was not associated with lower frequency of clinical restenosis or mortality.

Conclusions

Following proximal coronary artery intervention restenosis was more frequent in the LAD than in the LCX. Solely in the proximal LAD we found DES use to be associated with a lower risk of restenosis and death weighted against BMS.     

Late outcomes of drug‐eluting versus bare metal stents in saphenous vein grafts: Propensity score analysis

Objective : To compare late outcomes with the routine use of drug‐eluting stents (DES) compared with bare‐metal stents (BMS) during percutaneous intervention (PCI) of saphenous vein grafts (SVGs). Background : Safety concerns >1 year from stent implantation have been raised about DES used for PCI of SVGs in a small randomized clinical trial. However, there are few studies comparing late outcomes of DES and BMS in routine clinical practice. Methods : Clinical outcomes (nonfatal MI, cardiac mortality) were assessed in 74 consecutive patients who received BMS and 74 consecutive propensity score matched patients that received DES for PCI of SVGs. Clinical follow‐up was censored at 2 years ± 30 days for both stent groups. Results : At 2 years, the hazard ratio for DES compared with BMS for PCI of SVGs for target vessel revascularization was 0.54 (0.21–1.36), nonfatal MI or cardiac death was 0.68 (0.27–1.68), cardiac mortality 1.19 (0.32–4.45), and stent thrombosis 0.49 (0.09–2.66). Similar outcomes were observed stratified by propensity score quintile. Conclusions : The routine clinical use of DES for PCI of SVGs was associated with a safety profile that was similar to that of bare metal stents with a clear trend toward a less frequent need for reinterventions. © 2008 Wiley‐Liss, Inc.     

Effect of coronary endothelial function on outcomes in patients undergoing percutaneous coronary intervention

Numerous studies have documented the association between endothelial dysfunction and adverse cardiovascular events. For example, coronary artery disease is associated with functional and structural changes of the coronary arteries, resulting in ischemia or plaque rupture, and is highly associated with endothelial dysfunction. Recent data suggest that implantation of drug-eluting stents (DES) can induce coronary artery endothelial dysfunction at follow-up when compared with bare-metal stents (BMS) and that this endothelial dysfunction may be associated with late stent thrombosis. Indeed, despite the superiority of DES in preventing restenosis, the incidence of death and myocardial infarction is similar when comparing DES with BMS. Medical treatment, such as statins, angiotensin-converting enzyme inhibitors, or angiotensin receptor blockers, can improve endothelial dysfunction. Thus, administration of these drugs along with percutaneous coronary intervention (PCI) may be a low-risk strategy to provide therapeutic benefit by stabilizing unstable plaque or by suppressing new lesion formation in patients undergoing PCI.     

Use of drug‐eluting stents for chronic total occlusions: A systematic review and meta‐analysis

Aim: To perform a systematic review and meta‐analysis of studies reporting outcomes after drug‐eluting stent (DES) implantation in chronic total occlusions (CTOs). Methods: A review of publications and online databases in January 2010 retrieved 17 published studies that reported outcomes after DES implantation in CTOs: eight uncontrolled studies, seven nonrandomized comparative studies with bare‐metal stents (BMS), one post‐hoc analysis of a randomized trial, and one randomized trial. Data were pooled using random‐effects meta‐analysis models. Results: All published studies evaluated sirolimus‐ or paclitaxel‐eluting stents. All studies reporting comparative angiographic outcomes revealed less binary angiographic restenosis with DES implantation compared to BMS (odds ratio: 0.15, 95% CI: 0.08, 0.26). Over a mean follow‐up period of 18.9 ± 16.5 months, the cumulative incidence of death, myocardial infarction, or stent thrombosis was similar between DES and BMS in all studies. Target lesion revascularization (odds ratio: 0.13, 95% CI: 0.06, 0.26) and target vessel revascularization (odds ratio 0.18, 95% CI: 0.11, 0.31) at 6–12 months were consistently lower among DES‐treated patients. Similar patterns of safety and efficacy event rates were also observed in studies reporting >12 month outcomes. Conclusions: Compared with BMS, treatment of chronic total coronary occlusions with DES is associated with significant reductions in angiographic and clinical restenosis with similar safety. The consistency and magnitude of treatment effect across both individual trials and the pooled analysis establish DES as the preferred therapy for percutaneous revascularization of CTOs. © 2010 Wiley‐Liss, Inc.     

Comparing long‐term outcomes between drug‐eluting and bare‐metal stents in the treatment of cardiac allograft vasculopathy

Background: Cardiac allograft vasculopathy (CAV) is the leading cause of death after the first year following heart transplantation. We compared restenosis rates, mortality, and other major adverse cardiac events (MACE) between transplant recipients treated with DES and BMS for CAV. Methods: All patients from our heart transplant registry undergoing PCI with stenting for CAV were identified. Procedural data, baseline clinical characteristics, yearly coronary angiography, cardiac events and death were prospectively collected. Primary outcome was in‐stent restenosis (ISR). Secondary outcomes were in‐segment restenosis, target vessel revascularization (TVR), all‐cause mortality and combined MACE. Results: 36 lesions in 25 patients treated with DES were compared with 31 BMS‐treated lesions in 19 patients. There were no significant differences in baseline characteristics. 12‐month incidence of ISR was 0% with DES vs. 12.9% with BMS, P = 0.03. Over mean (±standard error) follow‐up of 51.1 ± 7.5 months this difference was significant for vessels ≤3 mm in diameter, hazard ratio (HR) DES vs. BMS 0.37 (95% CI 0.11 to 0.95) P = 0.037; but not for vessels >3 mm P = 0.45. However, there was no difference in overall longterm patency because of similar rates of in‐segment restenosis between DES and BMS, HR 1.13 (95% CI 0.43 to 2.97) P = 0.81. Also, the rates of TVR, death from any cause and combined MACE were similar; log rank P 0.88, 0.67, and 0.85, respectively. Conclusion: This study suggests that after PCI for cardiac allograft vasculopathy, despite a lower in‐stent restenosis rate in DES compared with BMS, in‐segment restenosis and clinical cardiac endpoints are similar. © 2009 Wiley‐Liss, Inc.     

Paclitaxel‐eluting balloon: From bench to bed

Since the first clinical angioplasty by Gruntzig in 1977, restenosis has been the primary drawback of percutaneous coronary intervention (PCI). In the balloon era. restenosis was correlated with elastic recoil and negative remodeling of the arterial wall. Later, introduction of stents proved to be a significant advance in reducing the elastic recoil and negative remodeling at the treatment site but stimulated proliferation, migration of smooth muscle cells, and neointimal hyperplasia, thereby generating a new type of restenosis, in‐stent restenosis. Brachytherapy and drug‐eluting stents (DES) may be considered the two breakthroughs against neointimal hyperplasia. However, concerns about stent thrombosis and incomplete elimination of in‐stent restenosis with DES in complex lesions and patients justify the pursuit of research in this field. Non‐stent based local drug delivery and particularly the use of paclitaxel‐eluting balloons could be one of these strategies. We aimed to review the concept, preclinical‐, and clinical data available with non‐stent based local drug delivery and, in particular, with paclitaxel‐eluting balloons. © 2009 Wiley‐Liss, Inc.     

Drug‐eluting stents versus bare‐metal stents for treatment of bare‐metal in‐stent restenosis

Objectives : We compared the long‐term outcomes of drug‐eluting stents (DES) versus bare‐metal stents (BMS) for treatment of bare‐metal in‐stent restenosis (ISR). Background : There are no randomized trials or observational studies directly comparing the safety and efficacy of DES versus BMS for treatment of bare‐metal ISR. Methods : We examined data on all patients who underwent percutaneous coronary intervention (PCI) for ISR at Cleveland Clinic between 05/1999 and 06/2007. We compared the efficacy and safety of DES to BMS for treating bare‐metal ISR. The primary end point was a composite of death, myocardial infarction (MI), or target lesion revascularization (TLR). The secondary endpoints were individual components of the primary endpoint. Results : Of the 931 patients identified over 8 years, 706 had bare‐metal ISR and met our study criteria. Of the 706 patients with bare‐metal ISR, 362 were treated with DES and 344 with BMS. There were 230 cumulative events for a median follow‐up of 3.2 years. After adjusting for 27 variables, DES were associated with lower primary endpoint compared to BMS for treatment of bare‐metal ISR (21% vs. 45%, adjusted hazard ratio [HR] 0.63; 95% confidence interval [CI], 0.42–0.95; P = 0.03). The individual secondary endpoint of death (8% vs. 24%, P = 0.005) favored DES, but MI (3% vs. 8%, P = 0.31), and TLR (13% vs. 20%, P = 0.23) failed to reach statistical significance. Conclusions : In our multivariate analysis of patients with bare‐metal ISR, DES use was associated with significantly lower death, MI, or TLR when compared to BMS. © 2010 Wiley‐Liss, Inc.     

Antiplatelet therapy following drug-eluting stent implantation: new clinical data and recommendations

Technological developments in percutaneous coronary interventions (PCI) allow the possibility for less invasive revascularization in an increasing number of patients with atherosclerotic coronary artery disease. Bare-metal stents (BMS) have considerably improved the efficacy of PCI in addition to greatly reducing restenosis. However, even with standard stents, restenosis has remained a significant limitation of this revascularization technique. The advent of drug-eluting stents (DES) has dramatically reduced in-stent restenosis and, as a result, the need for repeat revascularization. However, their potential thrombogenicity has raised concerns about their clinical utility and long-term safety. Indeed, there is a possible higher rate of late stent thrombosis (LST) with DES compared with BMS. Antiplatelet therapy has been shown to be efficient in preventing DES thrombosis. Nevertheless, in the future, significant improvement will occur to improve the safety and efficacy of this therapy. This article will summarize the pathophysiology and the epidemiology of stent thrombosis (ST). Definitions of definite, probable and possible ST will be described. Furthermore, clinical risk factors for ST will be clearly enumerated. Then, the various antiplatelet therapeutic strategies used to prevent ST will be taken in consideration. Finally, a summary of the major recommendations about antiplatelet therapy made by some of the most prestigious learned societies will be presented.     

Comparison of bare metal stents versus drug-eluting stents on clinical decision making in patients with previous percutaneous coronary intervention admitted for suspected acute coronary syndrome

To determine whether the decreased rate of restenosis observed with drug-eluting stents (DES) has changed the treatment of patients with recurrent symptoms after stent placement, we compared patients hospitalized with presumed cardiac symptoms within 1 year after placement of either a DES or a bare metal stent (BMS). In this retrospective, single-center study, cases were identified from consecutive patients who received a DES from March 2003 to July 2004 or a BMS from August 2001 to June 2002. No differences were noted in the rate of hospitalization, hospitalization for presumed cardiac symptoms, use of coronary angiography in patients hospitalized for presumed cardiac symptoms, or average interval to hospitalization. In contrast, restenosis and the need for additional revascularization procedures were higher in the BMS group. The primary indication for additional revascularization was restenosis in the BMS group and progression of coronary artery disease in the DES group. In the DES group, the need for revascularization was significantly higher in patients with multi- versus single-vessel coronary artery disease (26% vs 7%, p < 0.05). In conclusion, the rate of hospitalization and use of coronary angiography in patients with recurrent symptoms were similar in patients who received a BMS or DES, despite the decreased rates of restenosis and additional revascularization procedures observed with DESs.