Sirolimus-eluting stents for treatment of patients with long atherosclerotic lesions in small coronary arteries: double-blind, randomised controlled trial (E-SIRIUS)

BACKGROUND

Sirolimus-eluting stents have been developed to prevent restenosis in the treatment of coronary artery disease. We investigated the risk of restenosis with use of sirolimus-eluting stents compared with bare-metal stents to assess possible differences.

METHODS

We enrolled 352 patients in whom one coronary artery required treatment, with diameter 2.5-3.0 mm and lesion length 15-32 mm. We randomly assigned patients sirolimus-eluting stents (n=175) or bare-metal stents (control, n=177). At 8 months we assessed differences in minimum lumen diameter and binary restenosis within the lesion (restenosis of > or =50% diameter, including 5 mm vessel segments proximal and distal to stented segment). Patients were also followed up for 9 months for major adverse cardiac events. Analysis was by intention to treat.

FINDINGS

Stent implantation was successful in 100% of sirolimus-stent patients and 99.4% of controls. The mean diameter of treated coronary arteries was 2.55 mm (SD 0.37) and mean lesion length was 15.0 mm (6.0). Multiple stents were implanted in 170 (48%) patients. At 8 months, minimum lumen diameter was significantly higher with sirolimus-eluting stents than with control stents (2.22 vs 1.33 mm, p<0.0001). The rate of binary restenosis was significantly reduced with sirolimus-eluting stents compared with control stents (5.9 vs 42.3%, p=0.0001). Significantly fewer patients with sirolimus-eluting stents had major adverse cardiac events at 9 months than did controls (8.0 vs 22.6%, p=0.0002), due mainly to a lower need for target-lesion revascularisations (4.0 vs 20.9%, p<0.0001).

INTERPRETATION

Sirolimus-eluting stents are better than bare-metal stents for treatment of single long atherosclerotic lesions in a coronary vessel smaller than 3 mm in diameter.

Randomized Study to Evaluate Sirolimus-Eluting Stents Implanted at Coronary Bifurcation Lesions

Background— A sirolimus-eluting stent (Cypher, Cordis Corp) has been reported to markedly decrease restenosis in selected lesions; higher-risk lesions, including coronary bifurcations, have not been studied.

Methods and Results— This prospective study evaluated the safety and efficacy of sirolimus-eluting stents for treatment of coronary bifurcation lesions. Patients were randomly assigned to either stenting of both branches (group A) or stenting of the main branch with provisional stenting of the side branch (SB) (group B). Eighty-five patients (86 lesions) were enrolled. There was 1 case of unsuccessful delivery of any device at the bifurcation site. Given the high crossover, more lesions were treated with 2 stents (n=63) than with stent/balloon (n=22). Clinical follow-up at 6 months was completed in all patients and angiographic follow-up in 53 patients in group A (85.5%) and 21 in group B (95.4%). One patient died suddenly 4.5 months after the procedure. There were 3 cases of stent thrombosis (3.5%). The total restenosis rate at 6 months was 25.7%, and it was not significantly different between the double-stenting (28.0%) and the provisional SB-stenting (18.7%) groups. Fourteen of the restenosis cases occurred at the ostium of the SB and were focal. Target lesion revascularization was performed in 7 cases; target vessel failure occurred in 15 cases (17.6%).

Conclusions— These results are an improvement compared with historical controls using bare metal stents. Restenosis at the SB remains a problem. At this time, no statement can be made regarding the most appropriate technique to use when treating bifurcations with the Cypher stent.

Stent underexpansion and residual reference segment stenosis are related to stent thrombosis after sirolimus-eluting stent implantation

OBJECTIVES

We sought to determine the predictors of stent thrombosis after sirolimus-eluting stent (SES) implantation.

BACKGROUND

A number of cases of stent thrombosis have been reported after commercial release of the SES in the "real world," such that the U.S. Food and Drug Administration issued a warning.

METHODS

Fifteen patients who developed stent thrombosis after successful SES implantation were analyzed and compared with 45 matched control patients who had no evidence of stent thrombosis.

RESULTS

Minimum stent cross-sectional area (MSA) (4.3 +/- 1.6 mm(2) vs. 6.2 +/- 1.9 mm(2), p < 0.001) and stent expansion (0.65 +/- 0.18 vs. 0.85 +/- 0.14, p < 0.001) were significantly smaller in the stent thrombosis group than in the matched control patients. There was no significant difference in the rate of SES malapposition between the groups. However, the presence of a significant residual reference segment stenosis was more common in the stent thrombosis group compared with the matched control group (67% vs. 9%, p < 0.001). Independent predictors of stent thrombosis were stent underexpansion (p = 0.03) and a significant residual reference segment stenosis (p = 0.02).

CONCLUSIONS

Stent underexpansion and residual reference segment stenosis are associated with stent thrombosis after successful SES implantation.

Intracoronary stenting and angiographic results: strut thickness effect on restenosis outcome (ISAR-STEREO-2) trial

OBJECTIVES

We tested the hypothesis that thinner-strut stents are associated with a reduced rate of restenosis when comparing two stents with different design.

BACKGROUND

We have previously shown that, for two stents with similar design, the risk for restenosis is dependent on the strut thickness. It is unknown whether strut thickness preserves its relevance as a determinant of restenosis even in the presence of different stent designs.

METHODS

A total of 611 patients with symptomatic coronary artery disease were randomly assigned to receive either the thin-strut ACS RX Multilink stent (Guidant, Advanced Cardiovascular Systems, Santa Clara, California) (strut thickness 50 microm, interconnected ring design; n = 309) or the thick-strut BX Velocity stent (Cordis Corp., Miami, Florida) (strut thickness 140 microm, closed cell design; n = 302). The primary end point was angiographic restenosis (> or =50% diameter stenosis at follow-up angiography). Secondary end points were the incidence of target-vessel revascularization (TVR) and the combined rate of death and myocardial infarction (MI) at one year.

RESULTS

The incidence of angiographic restenosis was 17.9% in the thin-strut group and 31.4% in the thick-strut group, relative risk, 0.57 (95% confidence interval, 0.39 to 0.84), p < 0.001. A TVR due to restenosis was required in 12.3% of the thin-strut group and 21.9% of the thick-strut group, relative risk, 0.56 (95% confidence interval, 0.38 to 0.84), p = 0.002. No significant difference was observed in the combined incidence of death and MI at one year.

CONCLUSIONS

When two stents with different design are compared, the stent with thinner struts elicits less angiographic and clinical restenosis than the thicker-strut stent.

Impact of final stent dimensions on long-term results following sirolimus-eluting stent implantation: serial intravascular ultrasound analysis from the sirius trial

OBJECTIVES

We assessed the predictive value of minimum stent area (MSA) for long-term patency of sirolimus-eluting stents (SES) implantation compared to bare metal stents (BMS).

BACKGROUND

Although MSA is a consistent predictor of in-stent restenosis, its predictive value in BMS is still limited because of biologic variability in the restenosis process.

METHODS

From the SIRolImUS (SIRIUS) trial, 122 cases (SES: 72; BMS: 50) with complete serial intravascular ultrasound (IVUS) (baseline and 8-month follow-up) were analyzed. Postprocedure MSA and follow-up minimum lumen area (MLA) were obtained. Based on previous physiologic studies, adequate stent patency at follow-up was defined as MLA >4 mm(2).

RESULTS

In both groups, a significant positive correlation was observed between baseline MSA and follow-up MLA (SES: p < 0.0001, BMS: p < 0.0001). However, SES showed higher correlation than BMS (0.8 vs. 0.65) with a higher regression coefficient (0.92 vs. 0.59). The sensitivity and specificity curves identified different optimal thresholds of MSA to predict adequate follow-up MLA: 5 mm(2) for SES and 6.5 mm(2) for BMS. The positive predictive values with these cutoff points were 90% and 56%, respectively.

CONCLUSIONS

In this SIRIUS IVUS substudy, SES reduced both biologic variability and restenosis, resulting in increased predictability of long-term stent patency with postprocedure MSA. In addition, SES had a considerably lower optimal MSA threshold compared to BMS.

Predictors of subacute stent thrombosis: results of a systematic intravascular ultrasound study

BACKGROUND

Factors leading to subacute stent thrombosis after percutaneous coronary intervention (PCI) have not been well established. We assessed the pre- and post-PCI intravascular ultrasound (IVUS) characteristics of subacute stent thrombosis.

METHODS AND RESULTS

We analyzed 7484 consecutive patients without acute myocardial infarction who were treated with PCI and stenting and underwent IVUS imaging during the intervention. Twenty-seven (0.4%) had angiographically documented subacute closure <1 week after PCI (median time to subacute closure, 24 hours). Subacute closure lesions were compared with a control group (selected to be 3 times the abrupt closer group) matched by procedure date (within 6 months), age, gender, stable or unstable angina, lesion location, and additional treatment (balloon angioplasty or atherectomy). Postintervention IVUS did not identify a cause in 22% and did identify at least 1 cause for abrupt closure in 78% of patients (versus 33% in matched lesions, P=0.0002). In 48% of the patients, there were multiple causes in 48% (versus 3% in matched lesions, P<0.0001). Causes included dissection (17%), thrombus (4%), and tissue protrusion within the stent struts leading to lumen compromise lumen (4%). A total of 83% of patients with >1 of these abnormal morphologies also had reduced lumen dimensions post-PCI (final lumen <80% reference lumen). Preprocedural lesion characteristics were not different from matched lesions.

CONCLUSIONS

Subacute stent thrombosis is infrequently related to the preintervention lesion characteristics. Inadequate postprocedure lumen dimensions, alone or in combination with other procedurally related abnormal lesion morphologies (dissection, thrombus, or tissue prolapse), contribute to this phenomenon.

Paclitaxel-eluting balloons, paclitaxel-eluting stents, and balloon angioplasty in patients with restenosis after implantation of a drug-eluting stent (ISAR-DESIRE 3): a randomised, open-label trial

BACKGROUND

The best way to manage restenosis in patients who have previously received a drug-eluting stent is unknown. We investigated the efficacy of paclitaxel-eluting balloons (PEB), paclitaxel-eluting stents (PES), and balloon angioplasty in these patients.

METHODS

In this randomised, open-label trial, we enrolled patients older than 18 years with restenosis of at least 50% after implantation of any limus-eluting stent at three centres in Germany between Aug 3, 2009, and Oct 27, 2011. Patients were randomly assigned (1:1:1; stratified according to centre) to receive PEB, PES, or balloon angioplasty alone by means of sealed, opaque envelopes containing a computer-generated sequence. Patients and investigators were not masked to treatment allocation, but events and angiograms were assessed by individuals who were masked. The primary endpoint was diameter stenosis at follow-up angiography at 6-8 months. Primary analysis was done by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00987324.

FINDINGS

We enrolled 402 patients, of whom 137 (34%) were assigned to PEB, 131 (33%) to PES, and 134 (33%) to balloon angioplasty. Follow-up angiography at 6-8 months was available for 338 (84%) patients. PEB was non-inferior to PES in terms of diameter stenosis (38·0% [SD 21·5] vs 37·4% [21·8]; difference 0·6%, one-sided 95% CI 4·9%; p(non-inferiority)=0·007; non-inferiority margin of 7%). Findings were consistent in per-protocol analysis (p(non-inferiority)=0·011). PEB and PES were superior to balloon angioplasty alone (54·1% [25·0]; p(superiority)<0·0001 for both comparisons). Frequency of death, myocardial infarction, or target lesion thrombosis did not differ between groups.

INTERPRETATION

By obviating the need for additional stent implantation, PEB could be a useful treatment for patients with restenosis after implantation of a drug-eluting stent.

FUNDING

Deutsches Herzzentrum.

Indication of long-term endothelial dysfunction after sirolimus-eluting stent implantation

AIMS

Endothelial dysfunction has been related both to progression of atherosclerotic disease and to future cardiovascular events. We assessed local epicardial endothelial function 6 months after sirolimus-eluting stent (SES) or bare metal stent (BS) implantation.

METHODS AND RESULTS

In 12 patients (seven SES, five BS), endothelium-dependent vasomotion of a coronary segment 15 mm in length, starting 2 mm distal to the stent, was assessed with quantitative coronary angiography immediately after the procedure and at 6 months follow-up, after intracoronary infusion of acetylcholine. Intravascular ultrasound (IVUS) was performed and coronary flow reserve (CFR) assessed in all patients. At follow-up significant vasoconstriction was seen in SES (median 32% diameter reduction from baseline) but not in BS (median 2% reduction) patients after acetylcholine infusion (P=0.03 for SES vs. BS); endothelium-independent vasodilatation to nitrates did not differ significantly between groups (20% SES, 5% BS, P=0.14). IVUS revealed no late unhealed dissections and CFR was comparable between groups (SES 3.1 vs. BS 3.2, n.s.).

CONCLUSION

SES implantation may have an adverse effect on local endothelium-dependent vasomotor responses compared with BS implantation at 6 months. Long-term clinical consequences of this observation are still unknown.

Sirolimus-eluting stent implantation for unprotected left main coronary artery stenosis

OBJECTIVES

This study was designed to compare the clinical and angiographic outcomes of sirolimus-eluting stent (SES) and bare metal stent (BMS) implantation for unprotected left main coronary artery (LMCA) stenosis.

BACKGROUND

The safety and effectiveness of SES implantation for unprotected LMCA stenosis have not been ascertained.

METHODS

Elective SES implantation for de novo unprotected LMCA stenosis was performed in 102 consecutive patients with preserved left ventricular function from March 2003 to March 2004. Data from this group were compared to those from 121 patients treated with BMS during the preceding two years.

RESULTS

Compared to the BMS group, the SES group received more direct stenting, had fewer debulking atherectomies, had a greater number of stents, had more segments stented, and underwent more bifurcation stenting. The procedural success rate was 100% for both groups. There were no incidents of death, stent thrombosis, Q-wave myocardial infarction (MI), or emergent bypass surgery during hospitalization in either group. Despite less acute gain (2.06 +/- 0.56 mm vs. 2.73 +/- 0.73 mm, p < 0.001) in the SES group, SES patients showed a lower late lumen loss (0.05 +/- 0.57 mm vs. 1.27 +/- 0.90 mm, p < 0.001) and a lower six-month angiographic restenosis rate (7.0% vs. 30.3%, p < 0.001) versus the BMS group. At 12 months, the rate of freedom from death, MI, and target lesion revascularization was 98.0 +/- 1.4% in the SES group and 81.4 +/- 3.7% in the BMS group (p = 0.0003).

CONCLUSIONS

Sirolimus-eluting stent implantation for unprotected LMCA stenosis appears safe with regard to acute and midterm complications and is more effective in preventing restenosis compared to BMS implantation.

A paclitaxel-eluting stent for the prevention of coronary restenosis

BACKGROUND

Intimal hyperplasia and resulting restenosis limit the efficacy of coronary stenting. We studied a coronary stent coated with the antiproliferative agent paclitaxel as a means of preventing restenosis.

METHODS

We conducted a multicenter, randomized, controlled, triple-blind study to evaluate the ability of a paclitaxel-eluting stent to inhibit restenosis. At three centers, 177 patients with discrete coronary lesions (<15 mm in length, 2.25 to 3.5 mm in diameter) underwent implantation of paclitaxel-eluting stents (low dose, 1.3 microg per square millimeter, or high dose, 3.1 microg per square millimeter) or control stents. Antiplatelet therapies included aspirin with ticlopidine (120 patients), clopidogrel (18 patients), or cilostazol (37 patients). Clinical follow-up was performed at one month and four to six months, and angiographic follow-up at four to six months.

RESULTS

Technical success was achieved in 99 percent of the patients (176 of 177). At follow-up, the high-dose group, as compared with the control group, had significantly better results for the degree of stenosis (mean [+/-SD], 14+/-21 percent vs. 39+/-27 percent; P<0.001), late loss of luminal diameter (0.29+/-0.72 mm vs. 1.04+/-0.83 mm, P<0.001), and restenosis of more than 50 percent (4 percent vs. 27 percent, P<0.001). Intravascular ultrasound analysis demonstrated a dose-dependent reduction in the volume of intimal hyperplasia (31, 18, and 13 mm3, in the high-dose, low-dose, and control groups, respectively). There was a higher rate of major cardiac events in patients receiving cilostazol than in those receiving ticlopidine or clopidogrel. Among patients receiving ticlopidine or clopidogrel, event-free survival was 98 percent and 100 percent in the high-dose and control groups, respectively, at one month, and 96 percent in both at four to six months.

CONCLUSIONS

Paclitaxel-eluting stents used with conventional antiplatelet therapy effectively inhibit restenosis and neointimal hyperplasia, with a safety profile similar to that of standard stents.

Impact of Sirolimus-Eluting Stents on Outcome in Diabetic Patients

Background— Randomized clinical trials have shown that a sirolimus-eluting stent significantly reduces restenosis after percutaneous coronary revascularization. Diabetic patients are known to have a higher risk of restenosis compared with nondiabetic patients. The purpose of this analysis was to determine the impact of sirolimus-eluting stents on outcomes of diabetic compared with nondiabetic patients.

Methods and Results— The SIRIUS (SIRolImUS-coated Bx Velocity balloon-expandable stent in the treatment of patients with de novo coronary artery lesions) trial is a randomized, double-blind study that compared sirolimus-eluting and bare metal stent implantation in 1058 patients with de novo native coronary artery lesions. Diabetes mellitus was present in 279 (26%) patients (diabetes mellitus group, 131 patients received sirolimus-eluting stents and 148 patients received bare metal stents) and was absent in 778 patients (no–diabetes mellitus group, 402 patients received sirolimus-eluting stents and 376 patients received bare metal stents). At 270 days, target lesion revascularization was reduced in diabetic patients from 22.3% with bare metal stents to 6.9% with sirolimus-eluting stents ( P <0.001) and in nondiabetic patients from 14.1% to 2.99% ( P <0.001), respectively. Major adverse cardiac events were reduced in diabetic patients from 25% with bare metal stents to 9.2% with sirolimus-eluting stents ( P <0.001) and from 16.5% to 6.5% ( P <0.001) in nondiabetic patients, respectively.

Conclusions— Implantation of sirolimus-eluting stents compared with bare metal stents in de novo coronary lesions reduces major adverse cardiac events in patients with and without diabetes mellitus. However, among patients receiving sirolimus-eluting stents, there remains a trend toward a higher frequency of repeat intervention in diabetic patients compared with nondiabetic patients, particularly in the insulin-requiring patients.

Clinical restenosis after coronary stenting: perspectives from multicenter clinical trials

OBJECTIVES

We sought to evaluate clinical restenosis in a large population of patients who had undergone coronary stent placement.

BACKGROUND

One-year success after coronary stenting is limited mainly by restenosis of and requirement for repeat revascularization of the treated lesion. We studied 6,186 patients (6,219 lesions) pooled from several recently completed coronary stent trials. Clinical restenosis was defined using three different definitions: target lesion revascularization (TLR) beyond 30 days, target vessel revascularization (TVR) beyond 30 days, and target vessel failure (TVF), defined as TVR, any death, or myocardial infarction (MI) of the target vessel territory after hospital discharge.

RESULTS

By one year, 638 (12.2%) patients had TLR, 748 (14.3%) had TVR, and 848 (16.0%) had TVF, more than two-thirds higher than the rate of these end points at six months. The severity of angiographic restenosis (> or =50% follow-up diameter stenosis [DS]) in 419 of 1,437 (29%) patients undergoing routine angiographic follow-up correlated directly with the likelihood of TLR (73% vs. 26% for >70% DS compared with <60% DS). Smaller pretreatment minimum lumen diameter (MLD), smaller final MLD, longer stent length, diabetes mellitus, unstable angina, and hypertension were independent predictors of TLR. Prior MI and current smoking were negative predictors.

CONCLUSIONS

At one year after stenting, most clinical restenosis reflected TLR, which was predicted by the same variables previously associated with an increased risk of angiographic restenosis. The lower absolute rate of clinical restenosis relative to angiographic restenosis was due to infrequent TLR in lesions with less severe (<60% DS) angiographic renarrowing.

Examination of the in vivo mechanisms of late drug-eluting stent thrombosis: findings from optical coherence tomography and intravascular ultrasound imaging

OBJECTIVES

This study investigated the role of uncovered stent struts on late stent thrombosis (LST) after drug-eluting stent (DES) implantation with optical coherence tomography (OCT).

BACKGROUND

Autopsy studies have identified delayed healing and lack of endothelialization of DES struts as the hallmarks of LST. DES strut coverage has not previously been examined in vivo in patients with LST.

METHODS

We studied 54 patients, including 18 with DES LST (median 615 days after implant) undergoing emergent percutaneous coronary interventions and 36 matched DES control subjects undergoing routine repeat OCT and intravascular ultrasound (IVUS) who did not experience LST for ≥3 years. Thrombus aspiration was performed during emergent percutaneous coronary intervention before OCT and IVUS assessment.

RESULTS

By OCT, patients with LST--compared with control subjects--had a higher percentage of uncovered (median [interquartile range]) (12.27 [5.50 to 23.33] vs. 4.14 [3.00 to 6.22], p < 0.001) and malapposed (4.60 [1.85 to 7.19] vs. 1.81 [0.00 to 2.99], p < 0.001) struts. The mean neointimal thickness was similar in the 2 groups (0.23 ± 0.17 mm vs. 0.17 ± 0.09 mm, p = 0.28). By IVUS, stent expansion was comparable in the 2 groups, although positive remodeling was increased in patients with LST (mean vessel cross-section area 19.4 ± 5.8 mm(2) vs. 15.1 ± 4.6 mm(2), p = 0.003). Thrombus aspiration demonstrated neutrophils and eosinophils in most cases. By multivariable analysis, the length of segment with uncovered stent struts by OCT and the remodeling index by IVUS were independent predictors of LST.

CONCLUSIONS

In this in vivo case-controlled study, the presence of uncovered stent struts as assessed by OCT and positive vessel remodeling as imaged by IVUS were associated with LST after DES.

Clinical, angiographic, and procedural predictors of angiographic restenosis after sirolimus-eluting stent implantation in complex patients: an evaluation from the Rapamycin-Eluting Stent Evaluated At Rotterdam Cardiology Hospital (RESEARCH) study

BACKGROUND

The factors associated with the occurrence of restenosis after sirolimus-eluting stent (SES) implantation in complex cases are currently unknown.

METHODS AND RESULTS

A cohort of consecutive complex patients treated with SES implantation was selected according to the following criteria: (1) treatment of acute myocardial infarction, (2) treatment of in-stent restenosis, (3) 2.25-mm diameter SES, (4) left main coronary stenting, (5) chronic total occlusion, (6) stented segment >36 mm, and (7) bifurcation stenting. The present study population was composed of 238 patients (441 lesions) for whom 6-month angiographic follow-up data were obtained (70% of eligible patients). Significant clinical, angiographic, and procedural predictors of post-SES restenosis were evaluated. Binary in-segment restenosis was diagnosed in 7.9% of lesions (6.3% in-stent, 0.9% at the proximal edge, 0.7% at the distal edge). The following characteristics were identified as independent multivariate predictors: treatment of in-stent restenosis (OR 4.16, 95% CI 1.63 to 11.01; P<0.01), ostial location (OR 4.84, 95% CI 1.81 to 12.07; P<0.01), diabetes (OR 2.63, 95% CI 1.14 to 6.31; P=0.02), total stented length (per 10-mm increase; OR 1.42, 95% CI 1.21 to 1.68; P<0.01), reference diameter (per 1.0-mm increase; OR 0.46, 95% CI 0.24 to 0.87; P=0.03), and left anterior descending artery (OR 0.30, 95% CI 0.10 to 0.69; P<0.01).

CONCLUSIONS

Angiographic restenosis after SES implantation in complex patients is an infrequent event, occurring mainly in association with lesion-based characteristics and diabetes mellitus.

Short- and Long-Term Clinical Outcome After Drug-Eluting Stent Implantation for the Percutaneous Treatment of Left Main Coronary Artery Disease

Background— The impact of drug-eluting stent (DES) implantation on the incidence of major adverse cardiovascular events in patients undergoing percutaneous intervention for left main (LM) coronary disease is largely unknown.

Methods and Results— From April 2001 to December 2003, 181 patients underwent percutaneous coronary intervention for LM stenosis at our institution. The first cohort consisted of 86 patients (19 protected LM) treated with bare metal stents (pre-DES group); the second cohort comprised 95 patients (15 protected LM) treated exclusively with DES. The 2 cohorts were well balanced for all baseline characteristics. At a median follow-up of 503 days (range, 331 to 873 days), the cumulative incidence of major adverse cardiovascular events was lower in the DES cohort than in patients in the pre-DES group (24% versus 45%, respectively; hazard ratio [HR], 0.52 [95% CI, 0.31 to 0.88]; P =0.01). Total mortality did not differ between cohorts; however, there were significantly lower rates of both myocardial infarction (4% versus 12%, respectively; HR, 0.22 [95% CI, 0.07 to 0.65]; P =0.006) and target vessel revascularization (6% versus 23%, respectively; HR, 0.26 [95% CI, 0.10 to 0.65]; P =0.004) in the DES group. On multivariate analysis, use of DES, Parsonnet classification, troponin elevation at entry, distal LM location, and reference vessel diameter were independent predictors of major adverse cardiovascular events.

Conclusions— When percutaneous coronary intervention is undertaken at LM lesions, routine DES implantation, which reduces the cumulative incidence of myocardial infarction and the need for target vessel revascularization compared with bare metal stents, should currently be the preferred strategy.

Sirolimus-eluting vs uncoated stents for prevention of restenosis in small coronary arteries: a randomized trial

CONTEXT

Percutaneous coronary revascularization of small vessels is associated with a high restenosis rate. Sirolimus-eluting stents reduce restenosis in simple and previously untreated lesions of large coronary arteries, but their outcomes in small vessels have not been adequately investigated.

OBJECTIVE

To determine whether sirolimus-eluting stents are associated with a reduced 8-month rate of angiographic restenosis in comparison with an uncoated stent.

DESIGN, SETTING, AND PATIENTS

This was a randomized, multicenter, single-blind, prospective trial performed with 257 patients undergoing percutaneous coronary revascularization for ischemic heart disease, and who had a previously untreated atherosclerotic lesion located in a small segment with a diameter of 2.75 mm or less, in 20 Italian centers between August 2002 and December 2003.

INTERVENTION

Patients were randomly assigned to receive a sirolimus-eluting stent (129 patients) or an uncoated stent having an identical architecture and radiographic appearance (128 patients).

MAIN OUTCOME MEASURES

The primary end point was the 8-month binary in-segment restenosis rate; secondary end points included procedural success and the 8-month rate of major adverse cardiac and cerebrovascular events.

RESULTS

The mean (SD) reference diameter of the treated segment was 2.2 (0.28) mm; the lesion length, 11.84 (6.15) mm. After 8 months, the binary in-segment restenosis rate was 53.1% (60/113) in the patients receiving an uncoated stent and 9.8% (12/123) in those receiving a sirolimus-eluting stent (relative risk [RR], 0.18; 95% confidence interval [CI], 0.10-0.32; P<.001). Fewer patients randomized to sirolimus-eluting stents experienced major adverse cardiac events (12/129 [9.3%] vs 40/128 [31.3%]; RR, 0.30; 95% CI, 0.15-0.55; P<.001) mainly because of a reduction in target lesion revascularization (9/129 [7%] vs 27/128 [21.1%]; RR, 0.33; 95% CI, 0.14-0.70; P = .002) and myocardial infarction (2/129 [1.6%] vs 10/129 [7.8%]; RR, 0.20; 95% CI, 0.01-0.93; P = .04).

CONCLUSION

The use of sirolimus-eluting stents to treat atherosclerotic lesions in small coronary arteries reduces restenosis and may also reduce major adverse cardiac events.

Safety and performance of the second-generation drug-eluting absorbable metal scaffold in patients with de-novo coronary artery lesions (BIOSOLVE-II): 6 month results of a prospective, multicentre, non-randomised, first-in-man trial

BACKGROUND

Absorbable scaffolds were designed to overcome the limitations of conventional, non-absorbable metal-based drug-eluting stents. So far, only polymeric absorbable scaffolds are commercially available. We aimed to assess the safety and performance of a novel second-generation drug-eluting absorbable metal scaffold (DREAMS 2G) in patients with de-novo coronary artery lesions.

METHODS

We did this prospective, multicentre, non-randomised, first-in-man trial at 13 percutaneous coronary intervention centres in Belgium, Brazil, Denmark, Germany, Singapore, Spain, Switzerland, and the Netherlands. Eligible patients had stable or unstable angina or documented silent ischaemia, and a maximum of two de-novo lesions with a reference vessel diameter between 2·2 mm and 3·7 mm. Clinical follow-up was scheduled at months 1, 6, 12, 24, and 36. Patients were scheduled for angiographic follow-up at 6 months, and a subgroup of patients was scheduled for intravascular ultrasound, optical coherence tomography, and vasomotion assessment. All patients were recommended to take dual antiplatelet treatment for at least 6 months. The primary endpoint was in-segment late lumen loss at 6 months. We did analysis by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT01960504.

FINDINGS

Between Oct 8, 2013, and May 22, 2015, we enrolled 123 patients with 123 coronary target lesions. At 6 months, mean in-segment late lumen loss was 0·27 mm (SD 0·37), and angiographically discernable vasomotion was documented in 20 (80%) of 25 patients. Intravascular ultrasound assessments showed a preservation of the scaffold area (mean 6·24 mm(2) [SD 1·15] post-procedure vs 6·21 mm(2) [1·22] at 6 months) with a low mean neointimal area (0·08 mm(2) [0·09]), and optical coherence tomography did not detect any intraluminal mass. Target lesion failure occurred in four (3%) patients: one (<1%) patient died from cardiac death, one (<1%) patient had periprocedural myocardial infarction, and two (2%) patients needed clinically driven target lesion revascularisation. No definite or probable scaffold thrombosis was observed.

INTERPRETATION

Our findings show that implantation of the DREAMS 2G device in de-novo coronary lesions is feasible, with favourable safety and performance outcomes at 6 months. This novel absorbable metal scaffold could be an alternative to absorbable polymeric scaffolds for treatment of obstructive coronary disease.

FUNDING

Biotronik AG.

Contribution of stent underexpansion to recurrence after sirolimus-eluting stent implantation for in-stent restenosis

BACKGROUND

We used intravascular ultrasound (IVUS) to evaluate recurrence after sirolimus-eluting stent (SES) implantation treatment of in-stent restenosis (ISR).

METHODS AND RESULTS

Forty-eight ISR lesions (41 patients with objective evidence of ischemia) were treated with SES. Recurrent ISR was identified in 11 lesions (all focal); repeat revascularization was performed in 10. These were compared with 16 patients (19 lesions) without recurrence as documented by angiography. Nine of 11 recurrent lesions had a minimum stent area (MSA) <5.0 mm2 versus 5 of 19 nonrecurrent lesions (P=0.003); 7 of 11 recurrent lesions had an MSA <4.0 mm2 versus 4 of 19 nonrecurrent lesions (P=0.02); and 4 of 11 recurrent lesions had an MSA <3.0 mm2 versus 1 of 19 nonrecurrent lesions (P=0.03). A gap between SESs was identified in 3 of 11 recurrences versus 1 of 19 nonrecurrent lesions.

CONCLUSIONS

Stent underexpansion is a significant cause of failure after SES implantation treatment of ISR.

Evaluation of intracoronary stenting by intravascular optical coherence tomography

BACKGROUND

Conventional contrast cineangiography and intravascular ultrasound (IVUS) provide a limited definition of vessel microstructure and are unable to evaluate dissection, tissue prolapse, and stent apposition on a size scale less than 100 micro m.

OBJECTIVE

To evaluate the use of intravascular optical coherence tomography (OCT) to assess the coronary arteries in patients undergoing coronary stenting.

METHODS

OCT was employed in patients having percutaneous coronary interventions. Images were obtained before initial balloon dilatation and following stent deployment, and were evaluated for vessel dissection, tissue prolapse, stent apposition, and stent asymmetry. IVUS images were obtained before OCT, using an automatic pull back device.

RESULTS

42 stents were imaged in 39 patients without complications. Dissection, prolapse, and incomplete stent apposition were observed more often with OCT than with IVUS. Vessel dissection was identified in eight stents by OCT and two by IVUS. Tissue prolapse was identified in 29 stents by OCT and 12 by IVUS; the extent of the prolapse (mean (SD)) was 242 (156) microm by OCT and 400 (100) microm by IVUS. Incomplete stent apposition was observed in seven stents by OCT and three by IVUS. Irregular strut separation was identified in 18 stents by both OCT and IVUS.

CONCLUSIONS

Intracoronary OCT for monitoring stent deployment is feasible and provides superior contrast and resolution of arterial pathology than IVUS.

Intravascular ultrasound predictors of angiographic restenosis after sirolimus-eluting stent implantation

AIMS

In many countries, drug-eluting stent implantation is the dominant interventional strategy. We evaluated the clinical, angiographic, procedural, and intravascular ultrasound (IVUS) predictors of angiographic restenosis after sirolimus-eluting stent (SES) implantation.

METHODS AND RESULTS

SES implantation was successfully performed in 550 patients with 670 native coronary lesions. Six-month follow-up angiography was performed in 449 patients (81.6%) with 543 lesions (81.1%). Clinical, angiographic, procedural, and IVUS predictors of restenosis were determined. Using multivariable logistic regression analysis, the only independent predictors of angiographic restenosis were post-procedural final minimum stent area by IVUS [odds ratio (OR)=0.586, 95% confidence interval (CI) 0.387-0.888, P=0.012] and IVUS-measured stent length (OR=1.029, 95% CI 1.002-1.056, P=0.035). Final minimum stent area by IVUS and IVUS-measured stent length that best separated restenosis from non-restenosis were 5.5 mm2 and 40 mm, respectively. Lesions with final minimum stent area<5.5 mm2 and stent length>40 mm had the highest rate of angiographic restenosis [17.7% (11/62)], P<0.001 compared with other groups.

CONCLUSION

Independent predictors of angiographic restenosis after SES implantation were post-procedural final minimum stent area by IVUS and IVUS-measured stent length. The angiographic restenosis rate was highest in lesions with stent area<5.5 mm2 and stent length>40 mm.

Increased late mortality after sirolimus-eluting stents versus bare-metal stents in diseased saphenous vein grafts: results from the randomized DELAYED RRISC Trial

OBJECTIVES

We sought to provide long-term follow-up data of sirolimus-eluting stents (SES) versus bare-metal stents (BMS) in saphenous vein grafts (SVG) from the RRISC (Reduction of Restenosis In Saphenous vein grafts with Cypher) trial.

BACKGROUND

We have previously shown that, in SVG, the use of SES reduces 6-month restenosis and repeated revascularization procedures versus the use of BMS. These data are consistent with trials in native coronary arteries. However, recently published long-term follow-up data of these trials have revealed an increased risk of adverse events (particularly very late stent thrombosis) after SES.

METHODS

A total of 75 patients with 96 SVG lesions were randomized to SES versus BMS. All patients underwent clinical follow-up up to 3 years. Specific outcomes assessed in this secondary post-hoc analysis were all-cause mortality, myocardial infarction, and target vessel revascularization.

RESULTS

Thirty-eight patients received 60 SES for 47 lesions, whereas 37 patients received 54 BMS for 49 lesions. At a median follow-up time of 32 months (interquartile range 26.5 to 36 months), 11 deaths (7 cardiac, of which 1 was caused by very late stent thrombosis and, 3 were sudden) occurred after SES (29% [95% confidence interval (CI) 17% to 45%]) versus 0 after BMS (0% [95% CI 0% to 9%]) with an absolute difference of 29% ([95% CI 14% to 45%], p < 0.001). The rates of myocardial infarction and target vessel revascularization were not different: 18% and 34% after SES, respectively, versus 5% and 38% after BMS, respectively (p = 0.15 and p = 0.74, respectively).

CONCLUSIONS

In this secondary post-hoc analysis, BMS were associated with lower long-term mortality than SES for SVG disease. Also, the 6-month reduction in repeated revascularization procedures with SES was lost at longer-term follow-up. (RRISC Study: Reduction of Restenosis In Saphenous Vein Grafts With Cypher Sirolimus-Eluting Stent; http://clinicaltrials.gov/ct/show/NCT00263263?order=1; NCT00263263).

Results of Prevention of REStenosis with Tranilast and its Outcomes (PRESTO) trial

BACKGROUND

Restenosis after percutaneous coronary intervention (PCI) is a major problem affecting 15% to 30% of patients after stent placement. No oral agent has shown a beneficial effect on restenosis or on associated major adverse cardiovascular events. In limited trials, the oral agent tranilast has been shown to decrease the frequency of angiographic restenosis after PCI.

METHODS AND RESULTS

In this double-blind, randomized, placebo-controlled trial of tranilast (300 and 450 mg BID for 1 or 3 months), 11 484 patients were enrolled. Enrollment and drug were initiated within 4 hours after successful PCI of at least 1 vessel. The primary end point was the first occurrence of death, myocardial infarction, or ischemia-driven target vessel revascularization within 9 months and was 15.8% in the placebo group and 15.5% to 16.1% in the tranilast groups (P=0.77 to 0.81). Myocardial infarction was the only component of major adverse cardiovascular events to show some evidence of a reduction with tranilast (450 mg BID for 3 months): 1.1% versus 1.8% with placebo (P=0.061 for intent-to-treat population). The primary reason for not completing treatment was > or =1 hepatic laboratory test abnormality (11.4% versus 0.2% with placebo, P<0.01). In the angiographic substudy composed of 2018 patients, minimal lumen diameter (MLD) was measured by quantitative coronary angiography. At follow-up, MLD was 1.76+/-0.77 mm in the placebo group, which was not different from MLD in the tranilast groups (1.72 to 1.78+/-0.76 to 80 mm, P=0.49 to 0.89). In a subset of these patients (n=1107), intravascular ultrasound was performed at follow-up. Plaque volume was not different between the placebo and tranilast groups (39.3 versus 37.5 to 46.1 mm(3), respectively; P=0.16 to 0.72).

CONCLUSIONS

Tranilast does not improve the quantitative measures of restenosis (angiographic and intravascular ultrasound) or its clinical sequelae.

Treating chronic total occlusions using subintimal tracking and reentry: The STAR Technique

Successful recanalization of coronary total occlusions (CTOs) remains an area where improvements are needed. We propose an approach similar to the one utilized in treating some peripheral artery occlusions and aimed to create a subintimal dissection with distal reentry. A 0.014' hydrophilic wire with a J-configuration is utilized for this purpose. We applied this technique to CTO of native coronaries in 31 patients where previous attempts failed in 21 of them (67%). The right coronary artery (RCA) was the index vessel in 87% of patients. Recanalization of the vessel and of most of distal branches was achieved in 21 patients; patency of at least one major distal branch was achieved in 9 patients. Drug-eluting stents (DESs) were implanted in 53% of patients. Three patients had intraprocedural vessel perforation without consequences. Five patients (16%) had in-hospital non-Q-wave myocardial infarction. No other adverse events occurred at a mean follow-up of 5.1 +/- 3.7 months except for one noncardiac death. Angiographic follow-up was performed in 21 (67%) patients and 53% of them developed restenosis. Reintervention on the target vessel was performed in 11 patients (52%). Complete success with the procedure was originally obtained in 8 of the 10 patients who did not develop restenosis and in 8 of them DESs were originally implanted. This technique appears a promising approach to recanalize difficult total occlusions, particularly the ones localize on the RCA, which has the most important side branches located distally.

One-Year Coronary Bypass Graft Patency

Background— Off-pump coronary bypass surgery has become a widely used technique during recent years. However, limited data are available with regard to 1-year patency of bypass grafts implanted on the beating heart in unselected consecutive bypass surgery candidates. The aim of this study was to compare 1-year angiographic patency of bypass grafts done on the beating heart (off pump) with those done classically (on pump).

Methods and Results— The PRAGUE-4 trial randomized 400 consecutive nonselected cardiac surgery candidates into group A (on pump; n=192) and group B (off pump; n=208). One-year follow-up coronary angiography was done in 255 patients. The arterial graft patency after 1 year was 91% in both groups. Saphenous graft patency was 59% (on pump) versus 49% (off pump; P =NS). Saphenous graft patency per patient was lower in the off-pump group: 0.7 patent anastomosis per patient versus 1.1 patent anastomosis in the on-pump group ( P <0.01). There were 46% on-pump patients with all grafts patent versus 52% off-pump patients ( P =NS). Grafts anastomosed distally to collateralized chronic total occlusions of native coronary arteries remained patent in 100% on the left anterior descending artery compared with 23% on other arteries ( P <0.0001).

Conclusions— The patency of arterial coronary bypass grafts done on the beating heart is excellent and equal to grafts done on pump. The off-pump procedure in the unselected patient population results in fewer patent saphenous grafts per patient.