Effectiveness of drug-eluting stent implantation for patients with unprotected left main coronary artery stenosis

Left Main Coronary Artery Disease-Current Management and Future Perspectives

Due to its anatomical features, patients with an obstruction of the left main coronary artery (LMCA) have an increased risk of death. For years, coronary artery bypass grafting (CABG) has been considered as a gold standard for revascularization. However, notable advancements in the field of percutaneous coronary intervention (PCI) led to its acknowledgement as an important treatment alternative, especially in patients with low and intermediate anatomical complexity. Although recent years brought several random clinical trials that investigated the safety and efficacy of the percutaneous approach in LMCA, there are still uncertainties regarding optimal revascularization strategies. In this paper, we provide a comprehensive review of state-of-the-art diagnostic and treatment methods of LMCA disease, focusing on percutaneous methods.

Imaging during percutaneous coronary intervention for optimizing outcomes

Angiography is the current gold standard for imaging during percutaneous coronary interventions but has significant limitations. Catheter-based intravascular imaging techniques such as intravascular ultrasound and the more recent optical coherence tomography have the potential to overcome these limitations and thus optimize clinical outcomes. In this update, we discussed the current applications of the available imaging techniques, existing evidence, continuing unmet needs, and potential areas for further research.

Percutaneous Left Main Coronary Intervention: A Review of Plaque Modification in Left Main Percutaneous Coronary Intervention

Left main coronary artery (LMCA) stenosis has long been recognized as a marker of increased morbidity and mortality. Current treatment algorithms for LMCA stenosis consider both percutaneous coronary intervention (PCI) with drug eluting stents (DES) and coronary bypass surgery, each with advantages based on individual patient characteristics. Since the LMCA is the largest artery in the coronary tree, plaque volume and calcification is greater than other coronary segments and often extends to the distal bifurcation segment. In LMCA bifurcation lesions, larger minimal stent area is strongly associated with better outcome in the DES era. Plaque modification strategies such as rotational, orbital, or laser atherectomy are effective mechanisms to reduce plaque volume and alter compliance, facilitating stent delivery and stent expansion. We present a case of a calcified, medina class 1,1,1 LMCA lesion where intravascular ultrasound (IVUS) and orbital atherectomy were employed for optimal results. In this context, we review the evidence of plaque modification devices and the rationale for their use in unprotected left main PCI.

Two-year outcomes following unprotected left main stenting with first vs. new-generation drug-eluting stents: the FINE registry

AIMS

To assess two-year outcomes following first vs. new-generation drug-eluting stent (DES) implantation in unprotected left main (ULMCA) percutaneous coronary intervention.

METHODS AND RESULTS

All eligible patients from our two-centre registry treated with first and new-generation DES from October 2006 to November 2010 were analysed. The study objective was major adverse cardiac events (MACE), defined as all-cause mortality, target vessel revascularisation (TVR) and myocardial infarction (MI) at two years. In total, 186 patients were included: 93 (50.0%) treated with first vs. 93 (50.0%) with new-generation DES. No differences were observed in baseline clinical characteristics except for higher EuroSCORE with new-generation DES (3.6±2.5 vs. 4.6±2.7; p=0.007). No significant difference was observed in stenting techniques; two stents were used respectively in 53.8% vs. 44.1% (p=0.187). Notably, intravascular ultrasound guidance was more frequent with new-generation DES (46.2% vs. 61.3%; p=0.040). At 730.0 (interquartile range 365.5-1,224.5) days, there was a trend towards improved MACE with new-generation DES (31.2% vs. 19.6%; p=0.070) and a significant reduction in TVR (23.7% vs. 12.0%; p=0.038) and MI (4.3% vs. 0%; p=0.044). Notably, there were four cases of definite stent thrombosis (ST) with first vs. none with new-generation DES (p=0.044).

CONCLUSIONS

In our study, new-generation DES had a trend for less MACE and improved results with regard to MI, TVR and definite ST at two-year follow-up.

Reduction in incomplete stent apposition area caused by jailed struts after single stenting at left main bifurcation lesions: micro-CT analysis using a three-dimensional elastic bifurcated coronary artery model

Stent struts protruding into ostial side branch called “jailed strut” at bifurcation lesions is a likely cause of thrombus formation. We aimed to investigate the influences of multiple kissing balloon inflation (KBI) for stent expansion, and stent platform design, respectively, on the reduction of incomplete stent apposition area (ISA area) caused by jailed struts at a side-branch ostium, using a three-dimensional elastic left main (LM) bifurcated coronary artery model. The referenced LM bifurcation angle data of 209 patients were stratified by tertiles focusing on the angle between the LM trunk (LMT) and left anterior descending artery (LAD). A bifurcation model was fabricated with angles of 129°, 122.2°, and 76.4° for LMT–LAD, LMT–left circumflex (LCx), and LAD–LCx, respectively, and with diameters of 5, 3.75, and 3.5 mm for LMT, LAD, and LCx, respectively; these diameters fulfill Murray’s law. A 75 % stenosis was included along the LMT. One-time and three-time KBIs were conducted using two-link Nobori and three-link Xience Xpedition (n = 6 each). The ISA area was quantified using micro-CT. Three-time KBI was effective in reducing the ISA area compared with one-time KBI for both the Nobori (p = 0.05) and Xience Xpedition (p = 0.07). The ISA area was smaller in the Nobori than in the Xience Xpedition, both in one-time and three-time KBI (one-time KBI: p = 0.003; three-time KBI: p = 0.001). Our findings of this study on reducing the ISA area by focusing on an interventional technique and stent design may help to improve coronary bifurcation intervention for a possibly better long-term clinical outcome.

Comparison of the efficacy of drug-eluting stents versus bare-metal stents for the treatment of left main coronary artery disease

Background:

Recent studies reported that percutaneous coronary intervention with stent implantation was safe and feasible for the treatment of left main coronary artery (LMCA) disease in select patients. However, it is unclear whether drug-eluting stents (DESs) have better outcomes in patients with LMCA disease compared with bare-metal stent (BMS) during long-term follow-up in Chinese populations.

Methods:

From a perspective multicenter registry, 1136 consecutive patients, who underwent BMS or DES implantation for unprotected LMCA stenosis, were divided into two groups: 1007 underwent DES implantation, and 129 underwent BMS implantation. The primary outcome was the rate of major adverse cardiac events (MACEs), including cardiovascular (CV) death, myocardial infarction (MI), and target lesion revascularization (TLR) at 5 years postimplantation.

Results:

Patients in the DES group were older and more likely to have hyperlipidemia and bifurcation lesions. They had smaller vessels and longer lesions than patients in the BMS group. In the adjusted cohort of patients, the DES group had significantly lower 5 years rates of MACE (19.4% vs. 31.8%, P = 0.022), CV death (7.0% vs. 14.7%, P = 0.045), and MI (5.4% vs. 12.4%, P = 0.049) than the BMS group. There were no significant differences in the rate of TLR (10.9% vs. 17.8%, P = 0.110) and stent thrombosis (4.7% vs. 3.9%, P = 0.758). The rates of MACE (80.6% vs. 68.2%, P = 0.023), CV death (93.0% vs. 85.3%, P = 0.045), TLR (84.5% vs. 72.1%, P = 0.014), and MI (89.9% vs. 80.6%, P = 0.029) free survival were significantly higher in the DES group than in the BMS group. When the propensity score was included as a covariate in the Cox model, the adjusted hazard ratios for the risk of CV death and MI were 0.41 (95% confidence interval [CI]: 0.21–0.63, P = 0.029) and 0.29 (95% CI: 0.08–0.92, P = 0.037), respectively.

Conclusions:

DES implantation was associated with more favorable clinical outcomes than BMS implantation for the treatment of LMCA disease even though there was no significant difference in the rate of TLR between the two groups.

NUMERICAL SIMULATION ON THE EFFECTS OF DRUG-ELUTING STENTS WITH DIFFERENT LINKS ON HEMODYNAMICS AND DRUG CONCENTRATION DISTRIBUTION

The changes of hemodynamics and drug distribution caused by the implantation of drug-eluting stents (DES) have a significant influence on the in-stent restenosis. The present study numerically carried out a comparative study of hemodynamics and drug distribution using four different links of DES: Cordis BX velocity (Model A), Jostent flex (Model B), Sorin Carbostent (Model C), and DT-2 (Model D). The results showed that (1) low wall shear stress (WSS) distribution region spread widely in Model C (16.16%), with the least in Model B (10.35%); (2) Model C has relatively uniform drug concentration and causes of fewer low drug concentration region; and (3) Model A has the largest drug concentration, but also the most uneven distribution of drug. It was concluded that DES with circumferential links helps to improve in-stent restenosis as compared with that with longitudinal designs, and flexible links led to more uniformly and smoothly distributed blood flow than rigid links. However, the links with longitudinal designs had a better performance as drug release carrier than that with circumferential design. And if the links are too close together, the drug cannot be released effectively in the blood vessels. The current study helps to enhance our understanding of the performance of DES and provides assistance for optimal design and selection of DES.

Unprotected left main coronary stenting as alternative therapy to coronary bypass surgery in high surgical risk acute coronary syndrome patients

Acute coronary syndrome has a high mortality rate that dramatically increases in the presence of left main coronary artery (LMCA) disease. Over the past decades, coronary artery bypass graft (CABG) surgery has been commonly accepted as the standard of care for patients with LMCA stenosis and is still considered the first-line treatment in current practice guidelines. Percutaneous coronary intervention (PCI) of protected and unprotected LMCA has gained popularity and is increasingly utilized with comparable outcomes to CABG in randomized controlled trials. In-stent restenosis and the need for revascularization provide the main obstacle to LMCA revascularization. The advent of better PCI equipment, stents, ablative devices, intravascular ultrasound, hemodynamic support devices and antithrombotic agents have ignited a renewed interest in the practice of LMCA PCI, especially for high surgical risk patients who are neither candidates nor agreeable to CABG surgery. Herein, we review the studies comparing unprotected LMCA stenting with CABG surgery in regard to 3 main endpoints: mortality, major adverse events and the incidence of repeat revascularization.

Stenting of left main coronary artery stenosis: A to Z

For several decades, coronary artery bypass grafting (CABG) has been considered as the gold standard treatment of unprotected left main coronary artery (LMCA) disease. The marked improvement in technique and technology makes percutaneous coronary interventions (PCIs) feasible for patients with unprotected LMCA stenosis. The recent introduction of drug-eluting stents (DESs), together with advances in periprocedural and postprocedural adjunctive pharmacotherapies, has improved outcomes of PCIs of these lesions. Recent studies comparing efficacy and safety of PCIs using drug-eluting stents and CABG revealed comparable results in terms of safety and a lower need for repeat revascularisation for CABG. Patient selection for both the techniques directly impacts clinical outcome. Despite improvement in stent technology and operator experience, management can be challenging especially in LMCA bifurcation lesions and, therefore, an integrated approach combining advanced devices, tailored techniques, adjunctive support of physiological evaluation, and adjunctive pharmacological agents should be reinforced to improve clinical outcome.

Surgical candidacy and selection biases in nonemergent left main stenting: implications for observational studies

OBJECTIVES

This study sought to characterize reasons for surgical ineligibility in patients undergoing nonemergent unprotected left main (ULM) percutaneous coronary intervention (PCI) and to assess the potential for these reasons to confound comparative effectiveness studies of coronary revascularization.

BACKGROUND

Although both PCI and coronary artery bypass graft surgery are treatments for ULM disease, some patients are not eligible for both treatments, which may result in treatment selection biases.

METHODS

In 101 consecutive patients undergoing nonemergent ULM PCI, mixed methods were used to determine the prevalence of treatment selection dictated by surgical ineligibility and to identify the reasons cited for avoiding coronary artery bypass graft surgery. We then determined whether these reasons were captured by the ACC-NCDR (American College of Cardiology-National Cardiovascular Data Registry) Cath-PCI dataset to assess the ability of this registry to account for biases in treatment selection. Finally, the association of surgical eligibility with long-term outcomes after ULM PCI was assessed.

RESULTS

Treatment selection was dictated by surgical ineligibility in over half the ULM PCI cohort with the majority having reasons for ineligibility not captured by the ACC-NCDR. Surgical ineligibility was a significant predictor of mortality after adjustment for Society of Thoracic Surgeons (hazard ratio [HR]: 5.4, 95% confidence interval [CI]: 1.2 to 25), EuroSCORE (European System for Cardiac Operative Risk Evaluation) (HR: 5.9, 95% CI: 1.3 to 27), or NCDR mortality scores (HR: 6.2, 95% CI: 1.4 to 27).

CONCLUSIONS

Surgical ineligibility dictating treatment selection is common in patients undergoing nonemergent ULM PCI, occurs on the basis of risk factors not captured by the ACC-NCDR, and is independently associated with worse long-term outcomes after adjusting for standard risk scores.

Changes in Left Main Bifurcation Geometry After a Single-Stent Crossover Technique

Background—

We assessed geometric changes responsible for acute lumen loss at the left circumflex coronary artery (LCX) ostium after crossover stenting from the left anterior descending coronary artery (LAD) to the left main artery.

Methods and Results—

Twenty-three left main artery bifurcation lesions with a preprocedural angiographic diameter stenosis <50% at the LCX ostium were evaluated using prestenting and poststenting intravascular ultrasound pullbacks from both the LAD and the LCX. At the minimal lumen area (MLA) sites within the LCX ostium and at the LCX carina, the lumen, stent, plaque+media (P+M), and external elastic membrane (EEM) areas were measured; the EEM eccentricity was calculated at the LCX carina. The change in MLA within the LCX ostium (ΔL), the change in EEM area at the MLA site (ΔV), and the change in P+M area at the MLA site (ΔP) were calculated. The MLA within the LCX ostium significantly decreased from 5.4 mm 2 (first and third quartiles, 4.3 mm 2 , 7.2 mm 2 ) prestenting to 4.0 mm 2 (3.0 mm 2 , 4.8 mm 2 ) poststenting ( P <0.001). The percent change in MLA within the LCX ostium correlated with changes in EEM eccentricity ( r =−0.414, P =0.049) and percent change in EEM area at the MLA site ( r =0.626, P =0.001). A smaller distal carina angle between the LAD and the LCX before stenting was associated with a greater percent reduction in lumen ( r =0.472, P =0.023) and EEM ( r =0.402, P =0.048) after stenting. In 18 lesions with >10% reduction of MLA within the LCX ostium despite the lack of direct relationship between ΔL and ΔP at the MLA site, ΔP closely correlated with the ratio of ΔV to ΔL ( r =−0.953, P <0.001), suggesting that an increase in plaque at the LCX ostium contributed to the MLA loss relative to the decrease in EEM area.

Conclusions—

Lumen loss at the LCX ostium frequently occurred after crossover stenting from the distal LM to the LAD. The main mechanism was carina shift that was associated with a narrow angle between the LAD and LCX.

Preintervention angiographic and intravascular ultrasound predictors for side branch compromise after a single-stent crossover technique

A single stent crossover technique is the most common approach to treating bifurcation lesions. In 90 bifurcation lesions with side branch (SB) angiographic diameter stenosis <75%, we assessed preintervention intravascular ultrasound (IVUS; of main branch [MB] and SB) predictors for SB compromise (fractional flow reserve [FFR] <0.80) after a single stent crossover. Minimal lumen area (MLA) was measured within each of 4 segments (MB just distal to the carina, polygon of confluence, MB just proximal to polygon of confluence, and SB ostium). All lesions showed Thrombolysis In Myocardial Infarction grade 3 flow in the SB after MB stenting. Although angiographic diameter stenosis at the SB ostium increased from 26 ± 15% before the procedure to 36 ± 21% after stenting (p = 0.001), FFR <0.80 was observed in only 16 patients (18%). Negative remodeling (remodeling index <1) was seen in 83 (92%) lesions but did not correlate with FFR after stenting. Independent predictors for FFR after stenting were maximal balloon pressure (p = 0.002) and MLA of SB ostium before percutaneous coronary intervention (p <0.001), MLA within the MB just distal to the carina (p = 0.025), and plaque burden at the SB ostium before percutaneous coronary intervention (p = 0.005), but not angiographic poststenting diameter stenosis or minimal lumen diameter. For prediction of FFR <0.80 after percutaneous coronary intervention, the best cutoff of MLA within the SB ostium before percutaneous coronary intervention was 2.4 mm(2) (sensitivity 94%, specificity 69%). Also, the cutoff of plaque burden within the SB ostium before percutaneous coronary intervention was ≥51% (sensitivity 75%, specificity 71%). In 67 lesions with an MLA ≥2.4 mm(2) or plaque burden <50% before percutaneous coronary intervention, 63 (94%) showed FFR ≥0.80. However, FFR <0.80 was seen in only 12 (52%) of 23 lesions with an MLA <2.4 mm(2) and plaque burden ≥50%. In conclusion, there do not appear to be reliable IVUS predictors of functional SB compromise after crossover stenting.

Effect of intravascular ultrasound findings on long-term repeat revascularization in patients undergoing drug-eluting stent implantation for severe unprotected left main bifurcation narrowing

We studied the effect of the preprocedural intravascular ultrasound findings on stent expansion and the pre- and postprocedural findings on the long-term clinical outcomes in patients undergoing drug-eluting stent implantation for unprotected left main (LM) bifurcation disease. Using a left anterior descending (LAD) pullback, we evaluated the ostial LAD artery (3 mm distal to the carina), the polygon of confluence (POC; the confluent zone of the LAD artery and left circumflex artery), and the distal LM artery (3 mm just proximal to the POC). The measurements included the minimum lumen area (MLA) and minimum stent area within each segment. In 168 LM bifurcations, the preprocedural MLA and post-stenting minimum stent area within the LM artery were located within the POC in 41% and 70%, respectively. Independent predictors for the post-stent minimum stent area within the distal portion of LM artery above the LAD carina were the preprocedural lumen area of the LAD carina (β = 0.253, 95% confidence interval [CI] 0.10 to 0.36, p = 0.001) and preprocedural MLA within the POC (β = 0.205, 95% CI 0.04 to 0.23, p = 0.008). During the 41.8 ± 18.0-month follow-up period, 26 patients experienced cardiac events. In the multivariate Cox model, female gender (adjusted hazard ratio 2.56, 95% CI 1.173 to 5.594, p = 0.018) and preprocedural MLA within the POC (adjusted hazard ratio 0.829, 95% CI 0.708 to 0.971, p = 0.020) were independent predictors for the occurrence of events at 3 years of follow-up. In conclusion, as assessed by the LAD pullback, the preprocedural MLA within the POC was a surrogate reflecting the overall severity of LM bifurcation disease, contributed to the post-stent minimum stent area within the distal segment of LM bifurcation, and was a predictor of clinical events during follow-up.

Drug-eluting versus bare-metal stents in unprotected left main coronary artery stenosis a meta-analysis

OBJECTIVES

We undertook a meta-analysis to assess outcomes for drug-eluting stents (DES) and bare-metal stents (BMS) in percutaneous coronary intervention for unprotected left main coronary artery (ULMCA) stenosis.

BACKGROUND

Uncertainty exists regarding the relative performance of DES versus BMS in percutaneous coronary intervention for unprotected left main coronary stenosis.

METHODS

Of a total of 838 studies, 44 met inclusion criteria (n = 10,342). The co-primary end points were mortality, myocardial infarction (MI), target vessel/lesion revascularization (TVR/TLR), and major adverse cardiac events (MACE: mortality, MI, TVR/TLR).

RESULTS

Event rates for DES and BMS were calculated at 6 to 12 months, at 2 years, and at 3 years. Crude event rates at 3 years were mortality (8.8% and 12.7%), MI (4.0% and 3.4%), TVR/TLR (8.0% and 16.4%), and MACE (21.4% and 31.6%). Nine studies were included in a comparative analysis (n = 5,081). At 6 to 12 months the adjusted odds ratio (OR) for DES versus BMS were: mortality 0.94 (95% confidence interval [CI]: 0.06 to 15.48; p = 0.97), MI 0.64 (95% CI: 0.19 to 2.17; p = 0.47), TVR/TLR 0.10 (95% CI: 0.01 to 0.84; p = 0.01), and MACE 0.34 (95% CI: 0.15 to 0.78; p = 0.01). At 2 years, the OR for DES versus BMS were: mortality 0.42 (95% CI: 0.28 to 0.62; p < 0.01), MI 0.16 (95% CI: 0.01 to 3.53; p = 0.13), and MACE 0.31 (95% CI: 0.15 to 0.66; p < 0.01). At 3 years, the OR for DES versus BMS were: mortality 0.70 (95% CI: 0.53 to 0.92; p = 0.01), MI 0.49 (95% CI: 0.26 to 0.92; p = 0.03), TVR/TLR 0.46 (95% CI: 0.30 to 0.69; p < 0.01), and MACE 0.78 (95% CI: 0.57 to 1.07; p = 0.12).

CONCLUSIONS

Our meta-analysis suggests that DES is associated with favorable outcomes for mortality, MI, TVR/TLR, and MACE as compared to BMS in percutaneous coronary intervention for unprotected left main coronary artery stenosis.

Off-label use of drug-eluting versus bare metal stents: a lesion-specific systematic review of long-term outcomes

OBJECTIVE

The purpose of this systematic review was to evaluate differences in lesion-specific outcomes with the "off-label" use of drug-eluting stents (DES) versus bare metal stents (BMS).

METHODS

MEDLINE, PubMed, the Cochrane databases, and other Web were searched for studies evaluating off-label use of DES and BMS with the same characteristics. Of 1,258 abstracts or manuscripts reviewed, 112 studies were included (total N = 23,438). Studies were excluded if patients received both types of stent or no stent; lesion type was unknown; lesion-specific outcomes for ≥6 months were unavailable; or <25 patients were enrolled.

RESULTS

Overall mortality at 6-12 months was approximately 3% for BMS and DES for off-label use. Increase in mortality was greater from 6-12 months to 2 years with BMS than with DES (3.3%-9.1%; 2.8%-4.1%); however, rates were similar at 3 years (BMS: 18.8%; DES:15.3%). Myocardial Infarction rates were similar for both types at 6-12 months (BMS: 6.5%; DES: 6.0%). Overall rates of stent thrombosis were 1.8% and 1.7% for BMS and DES, respectively. Similar or slightly lower rates of stent thrombosis were seen for most lesion types, except higher rates for small vessels for BMS (5.2%) and true bifurcation for DES (3.3%). Rates of target lesion revascularization (TLR) were 7.5% for BMS and 19.6% for DES at 6-12 months. At 2-years TLR remained lower than DES. When the combined group was compared to registry data alone, similar values were seen.

CONCLUSIONS

Rates of mortality, myocardial infarction (MI), and stent thrombosis were similar in patients receiving BMS or DES, while TLR rates were lower in DES patients.

Percutaneous coronary intervention for unprotected left main coronary artery stenosis

Hemodynamically significant left main coronary artery stenosis (LMCA) is found in around 4% of diagnostic coronary angiograms and is known as unprotected LMCA stenosis if the left coronary artery and left circumflex artery has no previous patent grafts. Previous randomized studies have demonstrated a significant reduction in mortality when revascularization by coronary artery bypass graft (CABG) surgery was undertaken compared with medical treatment. Therefore, current practice guidelines do not recommend percutaneous coronary intervention (PCI) for such a lesion because of the proven benefit of surgery and high rates of restenosis with the use of bare metal stents. However, with the advent of drug-eluting stents (DES), the long term outcomes of PCI with DES to treat unprotected LMCA stenoses have been acceptable. Therefore, apart from the current guidelines, PCI for treatment of unprotected LMCA stenosis is often undertaken in individuals who are at a very high risk of CABG or refuse to undergo a sternotomy. Future randomized studies comparing CABG vs PCI using DES for treatment of unprotected LMCA stenosis would be a great advance in clinical knowledge for the adoption of appropriate treatment.

Long-term clinical outcomes of sirolimus- versus paclitaxel-eluting stents for patients with unprotected left main coronary artery disease: analysis of the MAIN-COMPARE (revascularization for unprotected left main coronary artery stenosis: comparison of percutaneous coronary angioplasty versus surgical revascularization) registry

OBJECTIVES

The aim of this study was to evaluate long-term clinical outcomes after implantation of sirolimus-eluting stents (SES) or paclitaxel-eluting stents (PES) among patients with unprotected left main coronary artery (LMCA) disease.

BACKGROUND

There have been few comparisons of long-term outcomes among currently available drug-eluting stents (DES) for the treatment of LMCA disease.

METHODS

A total of 858 consecutive patients with unprotected LMCA stenosis were treated with SES (n = 669) or PES (n = 189) between May 2003 and June 2006. Primary outcome was the composite of death, myocardial infarction (MI), or target vessel revascularization (TVR).

RESULTS

Baseline clinical and angiographic characteristics were similar in the 2 groups. During 3 years of follow-up, the adjusted risk of primary composite outcome was similar among the groups (SES vs. PES: 25.8% vs. 25.7%, hazard ratio [HR]: 0.95, 95% confidence interval [CI]: 0.64 to 1.41, p = 0.79). The 2 groups also showed a comparable adjusted rate of each component of outcome: death (9.1% vs. 11.0%, HR: 0.92, 95% CI: 0.47 to 1.80, p = 0.82), MI (8.1% vs. 8.0%, HR: 0.80, 95% CI: 0.43 to 1.48, p = 0.47), and TVR (12.1% vs. 10.6%, HR: 1.10, 95% CI: 0.53 to 2.29, p = 0.81). The 3-year rates of definite or probable stent thrombosis were 0.6% in the SES group and 1.6% in the PES group (adjusted p = 0.18).

CONCLUSIONS

In consecutive patients with unprotected LMCA disease undergoing DES implantation, SES and PES showed similar long-term clinical outcomes in terms of death, MI, repeat revascularization, and stent thrombosis.

Long-Term Safety and Effectiveness of Unprotected Left Main Coronary Stenting With Drug-Eluting Stents Compared With Bare-Metal Stents

Background— Limited information is available on long-term outcomes for patients with unprotected left main coronary artery disease who received drug-eluting stents (DES).

Methods and Results— In the multicenter registry evaluating outcomes among patients with unprotected left main coronary artery stenosis undergoing stenting with either bare metal stents (BMS) or DES, 1217 consecutive patients were divided into 2 groups: 353 who received only BMS and 864 who received at least 1 DES. The 3-year outcomes were compared by use of the adjustment of inverse-probability-of-treatment-weighted method. Patients receiving DES were older and had a higher prevalence of diabetes mellitus, hypertension, hyperlipidemia, and multivessel disease. In the overall population, with the use of DES, the 3-year adjusted risk of death (8.0% versus 9.5%; hazard ratio, 0.71; 95% confidence interval, 0.36 to 1.40; P =0.976) or death or myocardial infarction (14.3% versus 14.9%; hazard ratio, 0.83; 95% confidence interval, 0.49 to 1.40; P =0.479) was similar compared with BMS. However, the risk of target lesion revascularization was significantly lower with the use of DES than BMS (5.4% versus 12.1%; hazard ratio, 0.40; 95% confidence interval, 0.22 to 0.73; P =0.003). When patients were classified according to lesion location, DES was still associated with lower risk of target lesion revascularization in patients with bifurcation (6.9% versus 16.3%; hazard ratio, 0.38; 95% confidence interval, 0.18 to 0.78; P =0.009) or nonbifurcation (3.4% versus 10.3%; hazard ratio, 0.39; 95% confidence interval, 0.17 to 0.88; P =0.024) lesions with a comparable risk of death or myocardial infarction.

Conclusions— Compared with BMS, DES was associated with a reduction in the need for repeat revascularization without increasing the risk of death or myocardial infarction for patients with unprotected left main coronary artery stenosis.

Impact of intravascular ultrasound guidance on long-term mortality in stenting for unprotected left main coronary artery stenosis

BACKGROUND

Although intravascular ultrasound (IVUS) guidance has been useful in stenting for unprotected left main coronary artery stenosis, its impact on long-term mortality is still unclear.

METHODS AND RESULTS

In the MAIN-COMPARE registry, patients with unprotected left main coronary artery stenosis in a hemodynamically stable condition underwent elective stenting under the guidance of IVUS (756 patients) or conventional angiography (219 patients). Patients with acute myocardial infarction were excluded. The 3-year outcomes between the 2 groups were primarily compared using propensity-score matching in the entire and separate populations according to stent type. In 201 matched pairs of the overall population, there was a tendency of lower risk of 3-year morality with IVUS guidance compared with angiography guidance (6.0% versus 13.6%, log-rank P=0.063; hazard ratio, 0.54; 95% CI, 0.28 to 1.03; Cox-model P=0.061). In particular, in 145 matched pairs of patients receiving drug-eluting stent, the 3-year incidence of mortality was lower with IVUS guidance as compared with angiography guidance (4.7% versus 16.0%, log-rank P=0.048; hazard ratio, 0.39; 95% CI, 0.15 to 1.02; Cox model P=0.055). In contrast, the use of IVUS guidance did not reduce the risk of mortality in 47 matched pairs of patients receiving bare-metal stent (8.6% versus 10.8%, log-rank P=0.35; hazard ratio, 0.59; 95% CI, 0.18 to 1.91; Cox model P=0.38). The risk of myocardial infarction or target vessel revascularization was not associated with the use of IVUS guidance.

CONCLUSIONS

Elective stenting with IVUS guidance, especially in the placement of drug-eluting stent, may reduce the long-term mortality rate for unprotected left main coronary artery stenosis when compared with conventional angiography guidance.

Comparison of long-term efficacy of the paclitaxel-eluting stent versus the bare-metal stent for treatment of unprotected left main coronary artery disease

The use of paclitaxel-eluting stents (PES) for the treatment of unprotected left main coronary artery (LMCA) disease is controversial. Between January 2003 and December 2006, a total of 287 patients undergoing percutaneous coronary intervention for LMCA lesions were consecutively registered. Of those patients, 178 received PES and 109 received bare-metal stents (BMS). Estimated perioperative mortality rates were 7.3% and 6.8% for the BMS and PES groups, respectively (p=0.51). PES recipients had distal left main bifurcation lesions more frequently compared with BMS recipients (72 vs 42%, p<0.01). At an average follow-up of 35 months, the rates of major adverse cardiac events (4.5 vs 23.9%, adjusted odds ratio [OR] 0.23, 95% confidence interval [CI] 0.09 to 0.58, p<0.001) and target-lesion revascularization (2.2 vs 13.8%, adjusted OR 0.26, 95% CI 0.08 to 0.83, p<0.001) were significantly lower in the PES group than in the BMS group. Overall thrombotic event rates were 1.1% and 4.6% in the PES and BMS groups, respectively (p=0.08). Angiographic follow-up was performed in 61% and 59% of PES and BMS recipients, respectively. The angiographic restenosis rate was significantly lower in the PES group as compared with the BMS group (3.7 vs 23.4%, p<0.001). In conclusion, PES implantation provides a safe, effective therapy for unprotected LMCA disease and decreases the risk of major adverse cardiac events compared with BMS at a mean follow-up of 35 months.

Long-term outcome of percutaneous coronary intervention for unprotected left main coronary artery disease

OBJECTIVES

The aim of this study is to evaluate the in-hospital, 30 day and long-term outcomes after percutaneous coronary intervention for unprotected left main coronary artery disease.

BACKGROUNDS

Left main coronary artery (LMCA) diseases stenosis is a strong indication for coronary artery bypass grafting (CABG). With improved device technology, percutaneous coronary intervention (PCI) with drug-eluting stent (DES) stents had been recently advocated as an alternative procedure for the unprotected LMCA disease.

METHODS

Between January 2003 and February 2007, all unprotected LMCA PCI procedures were retrospectively collected. Outcomes were obtained by chart record review and telephone interview.

RESULTS

Fifty five consecutive patients with >50% diameter stenosis of LMCA undergoing PCI were analyzed. Indications for a percutaneous strategy were prohibitive surgical risks, or patient/physician preference. The procedural success rate was 98%. 41 patients (75%) received DES implantation. The majority of cases (n=33) were treated with a double-stent strategy. There were no in-hospital deaths. The clinical follow-up time was 867+/-410 days (range 20-1715). 18 (29%) patients experienced major adverse cardiac events, including 3 (5%) deaths, 4 (7%) myocardial infarctions, and 12 (21.8%) target lesion revascularizations (TLR) during follow-up. Multivariate analysis revealed hyperlipidemia (Hazard ratio, HR=6.2, p=0.024) and bifurcation involvement (HR=4.4, p=0.008) were independent predictors for MACE.

CONCLUSIONS

Our results showed that PCI with stenting was an acceptable treatment option for patients with LMCA stenosis. Involvement of the LMCA bifurcation remains a predictor for unfavorable outcome.

Multivessel disease: percutaneous coronary intervention for classic coronary artery bypass grafting indications

Multivessel coronary artery disease is characterized by involvement of greater than 1 epicardial coronary artery or the unprotected left main. The choice of revascularization strategy in this setting remains a critical issue in cardiology. Although coronary artery bypass grafting has traditionally been the revascularization strategy for most patients with multivessel disease, there has been a gradual shift toward percutaneous revascularization. Early randomized clinical trials showed coronary artery bypass grafting to be superior to medical therapy. However, trials comparing coronary artery bypass grafting to bare metal stenting have not shown a mortality benefit. Advancements in interventional techniques will continue to challenge the notion that coronary artery bypass grafting is the standard therapy for patients with multivessel coronary disease. Several ongoing randomized clinical trials comparing coronary artery bypass grafting to drug-eluting stents will provide valuable insight into the role of each procedure. In this article, we review the existing literature and discuss future directions in the management of the patient with multivessel disease.