Extracellular Matrix Proteomics Reveals Interplay of Aggrecan and Aggrecanases in Vascular Remodeling of Stented Coronary Arteries

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Background:

Extracellular matrix (ECM) remodeling contributes to in-stent restenosis and thrombosis. Despite its important clinical implications, little is known about ECM changes post–stent implantation.

Methods:

Bare-metal and drug-eluting stents were implanted in pig coronary arteries with an overstretch under optical coherence tomography guidance. Stented segments were harvested 1, 3, 7, 14, and 28 days post-stenting for proteomics analysis of the media and neointima.

Results:

A total of 151 ECM and ECM-associated proteins were identified by mass spectrometry. After stent implantation, proteins involved in regulating calcification were upregulated in the neointima of drug-eluting stents. The earliest changes in the media were proteins involved in inflammation and thrombosis, followed by changes in regulatory ECM proteins. By day 28, basement membrane proteins were reduced in drug-eluting stents in comparison with bare-metal stents. In contrast, the large aggregating proteoglycan aggrecan was increased. Aggrecanases of the ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) family contribute to the catabolism of vascular proteoglycans. An increase in ADAMTS-specific aggrecan fragments was accompanied by a notable shift from ADAMTS1 and ADAMTS5 to ADAMTS4 gene expression after stent implantation. Immunostaining in human stented coronary arteries confirmed the presence of aggrecan and aggrecan fragments, in particular, at the contacts of the stent struts with the artery. Further investigation of aggrecan presence in the human vasculature revealed that aggrecan and aggrecan cleavage were more abundant in human arteries than in human veins. In addition, aggrecan synthesis was induced on grafting a vein into the arterial circulation, suggesting an important role for aggrecan in vascular plasticity. Finally, lack of ADAMTS-5 activity in mice resulted in an accumulation of aggrecan and a dilation of the thoracic aorta, confirming that aggrecanase activity regulates aggrecan abundance in the arterial wall and contributes to vascular remodeling.

Conclusions:

Significant differences were identified by proteomics in the ECM of coronary arteries after bare-metal and drug-eluting stent implantation, most notably an upregulation of aggrecan, a major ECM component of cartilaginous tissues that confers resistance to compression. The accumulation of aggrecan coincided with a shift in ADAMTS gene expression. This study provides the first evidence implicating aggrecan and aggrecanases in the vascular injury response after stenting.

Everolimus-Eluting Stents or Bypass Surgery for Left Main Coronary Artery Disease

BACKGROUND

Patients with obstructive left main coronary artery disease are usually treated with coronary-artery bypass grafting (CABG). Randomized trials have suggested that drug-eluting stents may be an acceptable alternative to CABG in selected patients with left main coronary disease.

METHODS

We randomly assigned 1905 eligible patients with left main coronary artery disease of low or intermediate anatomical complexity to undergo either percutaneous coronary intervention (PCI) with fluoropolymer-based cobalt-chromium everolimus-eluting stents (PCI group, 948 patients) or CABG (CABG group, 957 patients). Anatomic complexity was assessed at the sites and defined by a Synergy between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery (SYNTAX) score of 32 or lower (the SYNTAX score reflects a comprehensive angiographic assessment of the coronary vasculature, with 0 as the lowest score and higher scores [no upper limit] indicating more complex coronary anatomy). The primary end point was the rate of a composite of death from any cause, stroke, or myocardial infarction at 3 years, and the trial was powered for noninferiority testing of the primary end point (noninferiority margin, 4.2 percentage points). Major secondary end points included the rate of a composite of death from any cause, stroke, or myocardial infarction at 30 days and the rate of a composite of death, stroke, myocardial infarction, or ischemia-driven revascularization at 3 years. Event rates were based on Kaplan-Meier estimates in time-to-first-event analyses.

RESULTS

At 3 years, a primary end-point event had occurred in 15.4% of the patients in the PCI group and in 14.7% of the patients in the CABG group (difference, 0.7 percentage points; upper 97.5% confidence limit, 4.0 percentage points; P=0.02 for noninferiority; hazard ratio, 1.00; 95% confidence interval, 0.79 to 1.26; P=0.98 for superiority). The secondary end-point event of death, stroke, or myocardial infarction at 30 days occurred in 4.9% of the patients in the PCI group and in 7.9% in the CABG group (P<0.001 for noninferiority, P=0.008 for superiority). The secondary end-point event of death, stroke, myocardial infarction, or ischemia-driven revascularization at 3 years occurred in 23.1% of the patients in the PCI group and in 19.1% in the CABG group (P=0.01 for noninferiority, P=0.10 for superiority).

CONCLUSIONS

In patients with left main coronary artery disease and low or intermediate SYNTAX scores by site assessment, PCI with everolimus-eluting stents was noninferior to CABG with respect to the rate of the composite end point of death, stroke, or myocardial infarction at 3 years. (Funded by Abbott Vascular; EXCEL ClinicalTrials.gov number, NCT01205776 .).

Biolimus-eluting stent with biodegradable polymer improves clinical outcomes in patients with acute myocardial infarction

OBJECTIVE

To investigate clinical outcomes of coronary intervention using a biolimus-eluting stent (BES) compared with a sirolimus-eluting stent (SES) in patients with acute myocardial infarction (AMI) in the Limus Eluted from A Durable versus ERodable Stent (LEADERS) coating trial at the final 5-year follow-up.

METHODS

The LEADERS trial is a multicentre all-comer study, where patients (n=1707) were randomised to percutaneous intervention with either BES containing biodegradable polymer or SES containing durable polymer. Out of 1707 patients enrolled in this trial, 573 patients had percutaneous coronary intervention for AMI (BES=280, SES=293) and were included in the current analysis. Patient-oriented composite endpoint (POCE, including all death, all myocardial infarction (MI) and all revascularisations), major adverse cardiac events (MACE, including cardiac death, MI and clinically indicated target vessel revascularisation) and stent thrombosis were assessed at 5-year follow-up.

RESULTS

The baseline clinical, angiographic and procedural characteristics were well matched between BES and SES groups. In all patients with AMI, coronary intervention with a BES, compared with SES, significantly reduced POCE (28.9% vs 42.3%; relative risk (RR) 0.61, 95% CI 0.47 to 0.82, p=0.001) at 5-year follow-up. There was also a reduction in MACE rate in the BES group (18.2% vs 25.9%; RR 0.67, 95% CI 0.47 to 0.95, p=0.025); however, there was no difference in cardiac death and stent thrombosis. In patients with ST-elevation MI (STEMI), coronary intervention with BES significantly reduced POCE (24.4% vs 39.3%; RR 0.55, 95% CI 0.36 to 0.85, p=0.006), MACE (12.6% vs 25.0%; RR 0.47, 95% CI 0.26 to 0.83, p=0.008) and cardiac death (3.0% vs 11.4%; RR 0.25, 95% CI 0.08 to 0.75, p=0.007), along with a trend towards reduction in definite stent thrombosis (3.7% vs 8.6%; RR 0.41, 95% CI 0.15 to 1.18, p=0.088), compared with SES.

CONCLUSIONS

BES, compared with SES, significantly improved safety and efficacy outcomes in patients with AMI, especially those with STEMI, at 5-year follow-up.

TRIAL REGISTRATION NUMBER

NCT 00389220.

Eptifibatide infusion versus placebo in high risk patients with non-st segment elevation acute coronary syndromes managed with urgent coronary artery bypass graft surgery. a prospective multicenter randomized placebo-controlled clinical trial

AIM

This randomized prospective clinical trial aimed to evaluate safety and efficacy of preoperative use of eptifibatide in high risk patients with non--ST--segment elevation acute coronary syndrome (NSTE--ACS), requiring urgent coronary artery bypass graft surgery (CABG).

METHODS

A total of 140 patients with NSTE--ACS eligible for urgent surgical revascularization received either eptifibatide (bolus plus infusion) 12--48 hours prior to surgery (n=72 patients) or placebo (normal saline; n=68 patients) followed by routinely administered enoxaparin and aspirin. Patients were regarded as unsuitable for percutaneous coronary intervention by the heart team. CABG was performed 4 hours after discontinuation of eptifibatide or placebo infusion. The primary end point was major adverse cardiac and cerebrovascular events (MACCE) defined as death, nonfatal myocardial infarction (MI), stroke and the need for re--hospitalization due to recurrent ischaemia at 12 months follow--up. Secondary endpoints included MACCE rate at 1 month, bleeding complications, platelet inhibition efficacy and correlation of platelet activity with MACCE rate.

RESULTS

Cumulative one year MACCE rate was 35% vs 14% in the control and treated group respectively (p=0.012). Mortality rate at 30 days follow--up was 10% vs 3% (p=0.021) and was not changed at 12 months follow--up. There was a significant difference between both groups regarding perioperative MI (22% vs. 8%, p=0.03). The rates of stroke, blood loss and blood transfusion were similar in both groups.

CONCLUSION

Preoperative use of eptifibatide vs. placebo is linked to significantly reduced 12--month MACCE rate in patients with NSTE--ACS requiring urgent CABG, while it simultaneously seems not to confer a greater risk of postoperative bleeding.

Long-term outcomes of percutaneous coronary interventions or coronary artery bypass grafting for left main coronary artery disease in octogenarians (from a Drug-Eluting stent for LefT main Artery registry substudy)

Percutaneous coronary intervention (PCI) with drug-eluting stents is an accepted alternative to surgery for the treatment of unprotected left main coronary artery (ULMCA) disease, but the long-term outcome in elderly patients is unclear. Aim of our study was to compare the clinical outcomes of octogenarians with ULMCA disease treated either with PCI with drug-eluting stents or coronary artery bypass grafting (CABG). The primary study end point was the composite of death, cerebrovascular accident, and myocardial infarction at follow-up. A total of 304 consecutive patients with ULMCA stenosis treated with PCI or CABG and aged ≥80 years were selected and analyzed in a large multinational registry. Two hundred eighteen were treated with PCI and 86 with CABG. During the hospitalization, a trend toward a higher mortality rate was reported in PCI-treated patients (3.5% vs 7.3%, p = 0.32). At a median follow-up of 1,088 days, the incidence of the primary end point was similar in the 2 groups (32.6% vs 30.2%, p = 0.69). Incidence of target vessel revascularization at follow-up was higher in PCI-treated patients (10% vs 4.2%, p = 0.05). At multivariate analysis, left ventricular ejection fraction was the only independent predictor of the primary end point (hazard ratio 0.95, 95% confidence interval 0.91 to 0.98, p = 0.001). After adjustment with propensity score, the revascularization strategy was not significantly correlated to the incidence of the primary end point (hazard ratio 0.98, 95% confidence interval 0.57 to 1.71, p = 0.95). In octogenarians, no difference was observed in the occurrence of the primary end point after PCI or CABG for the treatment of ULMCA disease. However, the rate of target vessel revascularization was higher in the PCI group.

Coronary artery bypass graft versus percutaneous coronary intervention with drug-eluting stent implantation for diabetic patients with unprotected left main coronary artery disease: the D-DELTA registry

AIMS

Data regarding the impact on clinical outcomes of PCI with DES implantation vs. CABG to treat unprotected left main coronary artery (ULMCA) disease in diabetic patients are still insufficient. The present study evaluated the short-term and long-term results of percutaneous and surgical revascularisation in diabetic patients with ULMCA disease in a large population.

METHODS AND RESULTS

A total of 826 diabetic patients with ULMCA stenosis who received DES (n=520) or underwent CABG (n=306) were selected and analysed from the DELTA registry. In-hospital MACCE was significantly higher in the CABG group, mainly driven by a higher incidence of MI. At four-year follow-up, freedom from death and the composite endpoint of death, MI and cerebrovascular accident (CVA) was similar in the two treatment groups (CABG 87.4%, PCI 82.5%, p=0.124, and CABG 85.4%, PCI 78.9%, p=0.11, respectively). Conversely, freedom from TVR and MACCE was significantly higher in the CABG compared to the PCI group (CABG 95.4%, PCI 79.4%, p<0.001, and CABG 81.9%, PCI 64.7%, p<0.001).

CONCLUSIONS

In diabetic patients with ULMCA disease with/without concomitant multivessel disease, PCI and CABG led to similar results in terms of death, MI and CVA. However, CABG was associated with less MACCE at long-term follow-up, primarily due to the higher repeat revascularisation rate with DES.

Circulating endothelial progenitor cells are inversely correlated with in-stent restenosis in patients with non-ST-segment elevation acute coronary syndromes treated with EPC-capture stents (JACK-EPC trial)

AIM

Aim of the study was to evaluate the association between circulating endothelial progenitor cells (EPCs) and angiographic outcomes after implantation of GenousTM stent in patients with non-ST-segment elevation acute coronary syndromes (ACS) (NSTE-ACS) undergoing urgent percutaneous coronary intervention (PCI).

METHODS

Sixty patients treated with EPC-capture stent (N.=30) or bare metal stents (BMS) (N.=30) receiving 80 mg atorvastatin and dual antiplatelet therapy (DAT) for 12 months. Restenosis was assessed after 6 months by quantitative coronary angiography (QCA) and major acute coronary events (MACE) evaluated after 6 and 12 months.

INCLUSION CRITERIA

de novo lesion >70% in native vessel, diameter 2.5-4 mm, lesion length <30 mm.

EXCLUSION CRITERIA

diabetes, previous revascularization, significant left main stenosis, chronic total occlusions (CTO) and multivessel disease.

RESULTS

Majority of patients in EPC-capture stent and BMS groups presented with NSTEMI (73.3% and 70%, respectively). Mean stent length was 20.1±8 and 19.9±10 mm, diameter 3±0.97 and 3.1±0.88 mm in respective groups. The binary restenosis was significantly lower in GenousTM (13 vs. 26.6%, P=0.04). Risk of MACE after 6 and 12 months were comparable in both groups. There was no stent thrombosis. Numbers of circulating EPCs were significantly approximately 2-fold higher during the ACS than after 6 months. Mobilization of EPCs during acute ischemia was significantly lower in patients who developed restenosis after 6 months (3 vs. 4.5 cells/μL, P=0.002) and it was negatively correlated with late-loss after 6 months (R=-0.42; P<0.03).

CONCLUSION

Use of GenousTM stents in NSTE-ACS is associated with lower restenosis rate than BMS at 6 months. There was no ST through 1 year. The number of circulating EPCs is inversely correlated with in-stent late loss (LL).

Implantation of the biodegradable polymer biolimus-eluting stent in patients with high SYNTAX score is associated with decreased cardiac mortality compared to a permanent polymer sirolimus-eluting stent: two year follow-up results from the "all-comers" LEADERS trial

BACKGROUND

The SYNTAX score (SXscore) has been shown to be an effective predictor of clinical outcomes in patients undergoing percutaneous coronary intervention (PCI).

METHODS AND RESULTS

The SXscore was prospectively collected in 1,397 of the 1,707 patients enrolled in the "all-comers" LEADERS trial (patients post-surgical revascularisation were excluded). Post hoc analysis was performed by stratifying clinical outcomes at two-year follow-up, according to one of three SXscore tertiles: SXlow ≤8 (n=464), 8<SXmid ≤16 (n=472) and SXhigh >16 (n=461). At two-year follow-up the rate of major adverse cardiovascular events was 18.4%, 12.0% and 9.4% in the SXhigh, SXmid, and SXlow tertile, respectively (HR 1.45; CI 1.21-1.74; p<0.01). There was a significantly higher rate of cardiac death in patients in the highest SXscore tertile (7% SXhigh versus 2.4% SXmid versus 1.8% SXlow; HR 2.22; CI 1.5-3.27; p<0.001). Within the SXhigh tertile the rate of cardiac death was significantly lower in patients treated with the biolimus-eluting stent compared with the sirolimus-eluting stent (4.7% versus 9.6%, HR 0.48; CI 0.23-0.99; p=0.046).

CONCLUSIONS

The SXscore when applied to an "all-comers" patient population allows for prospective risk stratification of patients undergoing PCI up to two years follow-up. In addition, the SXscore appears to separate the performance of devices in high risk patient groups.

Long-term clinical outcomes of biodegradable polymer biolimus-eluting stents versus durable polymer sirolimus-eluting stents in patients with coronary artery disease (LEADERS): 4 year follow-up of a randomised non-inferiority trial

BACKGROUND

The effectiveness of durable polymer drug-eluting stents comes at the expense of delayed arterial healing and subsequent late adverse events such as stent thrombosis (ST). We report the 4 year follow-up of an assessment of biodegradable polymer-based drug-eluting stents, which aim to improve safety by avoiding the persistent inflammatory stimulus of durable polymers.

METHODS

We did a multicentre, assessor-masked, non-inferiority trial. Between Nov 27, 2006, and May 18, 2007, patients aged 18 years or older with coronary artery disease were randomly allocated with a computer-generated sequence to receive either biodegradable polymer biolimus-eluting stents (BES) or durable polymer sirolimus-eluting stents (SES; 1:1 ratio). The primary endpoint was a composite of cardiac death, myocardial infarction, or clinically-indicated target vessel revascularisation (TVR); patients were followed-up for 4 years. Analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00389220.

FINDINGS

1707 patients with 2472 lesions were randomly allocated to receive either biodegradable polymer BES (857 patients, 1257 lesions) or durable polymer SES (850 patients, 1215 lesions). At 4 years, biodegradable polymer BES were non-inferior to durable polymer SES for the primary endpoint: 160 (18·7%) patients versus 192 (22·6%) patients (rate ratios [RR] 0·81, 95% CI 0·66-1·00, p for non-inferiority <0·0001, p for superiority=0·050). The RR of definite ST was 0·62 (0·35-1·08, p=0·09), which was largely attributable to a lower risk of very late definite ST between years 1 and 4 in the BES group than in the SES group (RR 0·20, 95% CI 0·06-0·67, p=0·004). Conversely, the RR of definite ST during the first year was 0·99 (0·51-1·95; p=0·98) and the test for interaction between RR of definite ST and time was positive (p(interaction)=0·017). We recorded an interaction with time for events associated with ST but not for other events. For primary endpoint events associated with ST, the RR was 0·86 (0·41-1·80) during the first year and 0·17 (0·04-0·78) during subsequent years (p(interaction)=0·049).

INTERPRETATION

Biodegradable polymer BES are non-inferior to durable polymer SES and, by reducing the risk of cardiac events associated with very late ST, might improve long-term clinical outcomes for up to 4 years compared with durable polymer SES.

FUNDING

Biosensors Europe SA, Switzerland.

The outcome of bifurcation lesion stenting using a biolimus-eluting stent with a bio-degradable polymer compared to a sirolimus-eluting stent with a durable polymer

AIMS

This study investigated the differences in clinical outcomes between patients with bifurcation lesions (BL) treated with a biolimus-eluting stent (BES) with a biodegradable polymer, and a sirolimus-eluting stent (SES) with a durable polymer.

METHODS AND RESULTS

The clinical outcomes were assessed in the 497 patients (BES 258, SES 239) enrolled in the multicentre, randomised LEADERS trial who underwent treatment of ≥1 BL (total=534 BL). At 12-months follow-up there was no significant difference in the primary endpoint of MACE, a composite of cardiac death, myocardial infarction and clinically indicated target vessel revascularisation (BES 12.8% vs. SES 16.3%, p=0.31). Patients treated with BES had comparable rates of cardiac death (BES 2.7% vs. SES 2.9%, p=1.00), numerically higher rates of myocardial infarction (BES 8.9% vs. SES 5.4%, p=0.17), and significantly lower rates of clinically indicated target vessel revascularisation (4.3% vs. 11.3%, p=0.004) when compared to those treated with SES. The rate of stent thrombosis at 12-months was 4.3% and 3.8% for BES and SES, respectively (p=0.82).

CONCLUSIONS

In the treatment of BL the use of BES lead to superior efficacy and comparable safety compared to SES.

Value of Age, Creatinine, and Ejection Fraction (ACEF Score) in Assessing Risk in Patients Undergoing Percutaneous Coronary Interventions in the ‘All-Comers' LEADERS Trial

Background—

The age, creatinine, and ejection fraction (ACEF) score (age/left ventricular ejection fraction+1 if creatinine >2.0 mg/dL) has been established as an effective predictor of clinical outcomes in patients undergoing elective coronary artery bypass surgery; however, its utility in “all-comer” patients undergoing percutaneous coronary intervention is yet unexplored.

Methods and Results—

The ACEF score was calculated for 1208 of the 1707 patients enrolled in the LEADERS trial. Post hoc analysis was performed by stratifying clinical outcomes at the 1-year follow-up according to ACEF score tertiles: ACEF low ≤1.0225, 1.0225< ACEF mid ≤1.277, and ACEF high >1.277. At 1-year follow-up, there was a significantly lower number of patients with major adverse cardiac event–free survival in the highest tertile of the ACEF score (ACEF low =92.1%, ACEF mid =89.5%, and ACEF high =86.1%; P =0.0218). Cardiac death was less frequent in ACEF low than in ACEF mid and ACEF high (0.7% vs 2.2% vs 4.5%; hazard ratio=2.22, P =0.002) patients. Rates of myocardial infarction were significantly higher in patients with a high ACEF score (6.7% for ACEF high vs 5.2% for ACEF mid and 2.5% for ACEF low ; hazard ratio=1.6, P =0.006). Clinically driven target-vessel revascularization also tended to be higher in the ACEF high group, but the difference among the 3 groups did not reach statistical significance. The rate of composite definite, possible, and probable stent thrombosis was also higher in the ACEF high group (ACEF low =1.2%, ACEF mid =3.5%, and ACEF high =6.2%; hazard ratio=2.04, P <0.001).

Conclusions—

ACEF score may be a simple way to stratify risk of events in patients treated with percutaneous coronary intervention with respect to mortality and risk of myocardial infarction.

Clinical Trial Registration—

URL: http://www.clinicaltrials.gov . Unique identifier: NCT00389220.