Treatment of Coronary Drug-Eluting Stent Restenosis by a Sirolimus- or Paclitaxel-Coated Balloon.

OBJECTIVES: The aim of this randomized controlled trial was to investigate a novel sirolimus-coated balloon (SCB) compared with the best investigated paclitaxel-coated balloon (PCB). BACKGROUND: Treatment of coronary in-stent restenosis (ISR) remains challenging. PCBs are an established treatment option outside the United States with a Class I, Level of Evidence: A recommendation in the European guidelines. However, their efficacy is better in bare-metal stent (BMS) ISR compared with drug-eluting stent (DES) ISR. METHODS: Fifty patients with DES ISR were enrolled in a randomized, multicenter trial to compare a novel SCB (SeQuent SCB, 4 µg/mm2) with a clinically proven PCB (SeQuent Please Neo, 3 µg/mm2) in coronary DES ISR. The primary endpoint was angiographic late lumen loss at 6 months. Secondary endpoints included procedural success, major adverse cardiovascular events, and individual clinical endpoints such as stent thrombosis, cardiac death, target lesion myocardial infarction, clinically driven target lesion revascularization, and binary restenosis. RESULTS: Quantitative coronary angiography revealed no differences in baseline parameters. After 6 months, in-segment late lumen loss was 0.21 ± 0.54 mm in the PCB group versus 0.17 ± 0.55 mm in the SCB group (p = NS; per-protocol analysis). Clinical events up to 12 months also did not differ between the groups. CONCLUSIONS: This first-in-man comparison of a novel SCB with a crystalline coating shows similar angiographic outcomes in the treatment of coronary DES ISR compared with a clinically proven PCB. (Treatment of Coronary In-Stent Restenosis by a Sirolimus [Rapamycin] Coated Balloon or a Paclitaxel Coated Balloon [FIM LIMUS DCB]; NCT02996318).

Review: Stent fracture in the drug-eluting stent era.

Stent fracture has been recognized as one cause of stent failure and has been associated with in-stent restenosis and stent thrombosis, even in 2nd-generation drug-eluting stents. Given the wide use of drug-eluting stents and paucity of contemporary data available concerning stent fracture, we reviewed clinical studies and the Food and Drug Administration's Manufacturer and User Device Experience (MAUDE) database to analyze the current trends, mechanisms, predictors, outcomes and treatment for stent fracture.

Comparison of outcomes after percutaneous coronary intervention among different coronary subsets (stable and unstable angina pectoris and ST-segment and non-ST-segment myocardial infarction).

Percutaneous coronary intervention in the setting of acute myocardial infarction is known to predict stent thrombosis (ST). This study aims to compare the ST rates across different coronary subsets. This was an observational cohort study from a large, single-center registry. Included were 12,198 consecutive patients who underwent percutaneous coronary intervention with stenting. Patients were categorized according to their clinical presentation: stable angina pectoris (SAP, n = 3,700), unstable angina pectoris (UAP, n = 2,845), non-ST-segment elevation myocardial infarction (NSTEMI, n = 4,083), and ST-segment elevation myocardial infarction (STEMI, n = 1,570). The study end points were ST rates at 1 year. Patients with STEMI were younger with a lower prevalence of cardiovascular risk factors, except for smoking. More type C lesions were treated in STEMI, whereas drug-eluting stents were used less frequently in patients with STEMI compared with the other groups. Definite ST at 1 year was highest in patients with STEMI (1.4%; vs SAP, 0.4%; UAP, 0.5%; NSTEMI, 0.5%; p <0.001). One-year definite/probable ST rates were SAP, 0.8%; UAP, 1.1%; NSTEMI, 1.4%; and STEMI, 3.2% (p <0.001). On multivariable analysis, STEMI independently predicts definite ST (hazards ratio [HR] 3.07, 95% confidence interval [CI] 1.32 to 7.10), whereas both STEMI (HR 3.36, 95% CI 1.84 to 6.12) and NSTEMI (HR 2.04, 95% CI 1.20 to 3.07) were independent predictors of definite/probable ST. Clopidogrel cessation was the strongest predictor of ST (definite ST, HR 17.00, 95% CI 7.54 to 38.31; definite/probable ST, HR 4.69, 95% CI 2.39 to 9.20). In conclusion, in patients who underwent percutaneous coronary intervention, the acuity of clinical presentation corresponds to an increase in ST incidence. Adherence to clopidogrel is critical to prevent ST in patients who underwent percutaneous coronary intervention, especially in STEMI.

Intra-stent tissue evaluation within bare metal and drug-eluting stents > 3 years since implantation in patients with mild to moderate neointimal proliferation using optical coherence tomography and virtual histology intravascular ultrasound.

OBJECTIVE: We aimed to compare neointimal tissue characteristics between bare-metal stents (BMS) and drug-eluting stents (DES) at long-term follow-up using optical coherence tomography (OCT) and virtual histology intravascular ultrasound (VH-IVUS). BACKGROUND: Neoatherosclerosis in neointima has been reported in BMS and in DES. METHODS: Thirty patients with 36 stented lesions [BMS (n=17) or DES (n=19)] >3years after implantation were prospectively enrolled. OCT and VH-IVUS were performed and analyzed independently. Stents with ≥70% diameter stenosis were excluded. RESULTS: The median duration from implantation was 126.0months in the BMS group and 60.0months in the DES group (p <0.001). Lipid-laden intima (58.8% vs. 42.1%, p=0.317), thrombus (17.6% vs. 5.3%, p=0.326), and calcification (35.3% vs. 26.3%, p=0.559) did not show significant differences between BMS and DES. When divided into 3 time periods, the cumulative incidence of lipid-laden neointima from >3years to <9years was similar between BMS and DES (42.9% vs. 42.1%, p=1.000). Furthermore, it continued to gradually increase over time in both groups. OCT-derived thin-cap fibroatheroma (TCFA) was observed in 17.6% of BMS- and 5.3% of DES-treated lesions (p=0.326). No stents had evidence of intimal disruption. The percentage volume of necrotic core (16.1% [9.7, 20.3] vs. 9.7% [7.0, 16.5], p=0.062) and dense calcium (9.5% [3.8, 13.6] vs. 2.7% [0.4, 4.9], p=0.080) in neointima tended to be greater in BMS-treated lesions. Intra-stent VH-TCFA (BMS vs. DES 45.5% vs. 18.2%, p=0.361) did not differ significantly. CONCLUSION: At long-term follow-up beyond 3 years after implantation, the intra-stent neointimal tissue characteristics appeared similar for both BMS and DES.

Impact of early versus late clopidogrel discontinuation on stent thrombosis following percutaneous coronary intervention with first- and second-generation drug-eluting stents.

Premature antiplatelet therapy discontinuation (ATD) after drug-eluting stent (DES) implantation is known to predict stent thrombosis (ST). However, recent data suggest that a shorter antiplatelet therapy duration is safe with newer generation DESs. The study aimed to compare the impact of early and late clopidogrel ATDs on ST in a real-world registry of first- and second-generation DES use. A total of 6,236 patients who underwent DES implantation were analyzed retrospectively: 4,217 received first-generation DESs (sirolimus- and paclitaxel-eluting stents) and 2,019 received second-generation DESs (everolimus-eluting stents). Within each DES cohort, patients were categorized into timing of clopidogrel discontinuation within 1 year: early (<3 months), late (3 to 12 months), and continued. ST rates and clinical outcomes at 1 year were analyzed. There were 341 patients (8.1%) in the first-generation DES group and 126 patients (6.2%) in the second-generation DES group who discontinued clopidogrel within the first year. Definite and probable ST rates were 3.8% for early ATD, 2.5% for late ATD, and 0.5% for continued (p = 0.001) in the first-generation DES cohort, whereas there were no definite or probable ST events in early and late ATDs and 0.5% for continued in the second-generation DES cohort. Major adverse cardiac event rates were 9.9% for early ATD, 5.6% for late ATD, and 0.9% for continued (p <0.001) in the first-generation DES cohort and 5.5% for early ATD, 7.4% for late ATD, and 1.5% for continued (p <0.001) in the second-generation DES cohort. In conclusion, ATD within the first year is associated with increased ST events with first-generation DESs, whereas ATD appears safe with second-generation DESs with regard to ST. However, ATD is associated with greater mortality and major adverse cardiac events in both first- and second-generation DESs. Thus, this study supports ATD if required based on physician discretion with the use of second-generation DESs but cannot rule out potential benefit for longer duration of dual antiplatelet therapy even when second-generation DESs are used.

Long-term safety and efficacy of second-generation everolimus-eluting stents compared to other limus-eluting stents and bare metal stents in patients with acute coronary syndrome.

OBJECTIVES: This study aimed to investigate the long-term safety and efficacy of everolimus-eluting stents (EES) compared with other limus-eluting stents and bare metal stents (BMS) in ACS patients. BACKGROUND: There have been concerns about the long-term safety of drug-eluting stents in the setting of acute coronary syndrome. METHODS: The study cohort included 1,612 patients presenting with acute coronary syndrome who underwent BMS, SES, E-ZES, or EES implantation. End points included probable or definite stent thrombosis and major adverse cardiovascular events (MACE), defined as a composite of all-cause death, Q-wave myocardial infarction, and target lesion revascularization up to 3 years. RESULTS: The overall MACE rates were significantly higher for both BMS and SES, but not E-ZES, when compared with EES (EES vs. BMS: HR 2.68, 95% CI 1.91-3.78, P <0.001; EES vs. SES: HR 1.75, 95% CI 1.24-2.47, P = 0.001 and EES vs. E-ZES: HR 1.08, 95% CI 0.65-1.77, P = 0.72). Stent thrombosis rates were similar for EES, E-ZES, and BMS but higher for SES throughout the 3-year follow-up (EES vs. BMS: HR 1.02, 95% CI: 0.31-3.35, P = 0.973; EES vs. SES: HR 4.90, 95% CI: 1.75-13.69, P = 0.002 and EES vs. E-ZES: HR 1.63, 95% CI 0.37-7.31, P = 0.449). CONCLUSIONS: There was an improvement in the long-term outcome for MACE with EES when compared to earlier-generation stents, but this was comparable with the 2nd-generation E-ZES. There was no additional risk of early or late stent thrombosis in EES when compared with BMS.

Intravascular ultrasound analysis to determine the relationship between high-density lipoprotein cholesterol and lesion characteristics in patients with coronary artery disease.

OBJECTIVES: This study utilized grayscale intravascular ultrasound (IVUS) to explore the relationship between high-density lipoprotein cholesterol (HDL-C) levels and culprit lesion characteristics in patients with coronary artery disease. BACKGROUND: Low HDL-C is associated with an increased risk of cardiovascular events. Previous IVUS studies have suggested a significant association between lesion characteristics and cardiovascular events. METHODS: According to HDL-C levels, 120 patients who underwent IVUS for native, de novo coronary lesions before any intervention were divided into a low HDL-C group (<40 mg/dL, n = 60) and a high HDL-C group (≥40 mg/dL, n = 60). Quantitative and qualitative IVUS analyses were performed to compare lesion characteristics. RESULTS: Quantitative IVUS measurements showed no significant differences between the 2 groups. HDL-C level was not significantly correlated with remodeling index (r = 0.03, P = 0.78). However, attenuated plaque was more frequent in the low HDL-C group (48.3% vs. 28.3%, P = 0.02) and a greater percentage of attenuated plaque was found in this group (32.5 ± 21.3% vs. 21.0 ± 11.0%, P = 0.02). Moreover, when categorized into 4 groups according to HDL-C levels, the proportion of attenuated plaque (64.7% in group with <30 mg/dL, 41.9% in group with 30-39 mg/dL, 36.4% in group with 40-59 mg/dL, and 6.3% in group with ≥60 mg/dL; P = 0.001 for trend) was significantly different among groups. On multivariate analysis, only HDL-C and male gender were independently associated with the presence of attenuated plaque at the culprit lesions. CONCLUSIONS: Patients with low levels of HDL-C may be at increased risk of having a higher incidence of attenuated plaques.

Current application and bioavailability of drug-eluting stents.

INTRODUCTION: Drug-eluting stents (DES) were developed to reduce the restenosis rate of bare metal stents (BMS) and comprises three main components: i) a metallic scaffold; ii) an antiproliferative drug to reduce or abolish the formation of the neointima; and iii) the polymer, which both enables and controls drug elution into the vessel wall. Over the years, growing evidence has been reported on the safety and efficacy for different indications of DES. AREAS COVERED: Since the introduction of first-generation DES, the technology has been refined, including changes in the alloy, stent design, polymer, drug and drug dose. In 2014, we will usher in a third generation of DES, which will include biodegradable polymers, polymer-free DES and bioabsorbable scaffolds. EXPERT OPINION: In recent years, considerable progress has been made in DES development. The BMS platform set the groundwork for the development of metal scaffolds with drug-eluting capability to prevent restenosis. Importantly, extensive research has shown long-term safety and efficacy of the newer generation DES. Available data suggest that DES can be safely and effectively used to treat a complex subset of patients and lesions, including patients presenting with acute myocardial infarction, lesions in saphenous vein grafts, chronic total occlusions, multivessel disease, small vessels, long lesions and bifurcations. One of the safety targets is to eliminate stent thrombosis.