Correlates and Outcomes of Late and Very Late Drug-Eluting Stent Thrombosis: Results From DESERT (International Drug-Eluting Stent Event Registry of Thrombosis)

ObjectivesThe aim of this study was to identify clinical, procedural, and angiographic correlates of late/very late drug-eluting stent (DES) thrombosis as well as to determine the clinical outcomes of these events.BackgroundLate/very late DES thromboses are a poorly studied phenomenon, partly due to the relative infrequency of these events, even in large cohort studies.MethodsIn the DESERT (International Drug-Eluting Stent Event Registry of Thrombosis), a retrospective, case-control registry, 492 cases of late/very late definite DES thrombosis from 21 international sites were matched in a 1:1 fashion with controls without stent thrombosis (ST). Controls were matched according to 2 criteria: same enrolling institution and date of initial DES implantation. Baseline and procedural variables were collected, and clinical follow-up was obtained for patients with ST as long as 1 year after the event. Offline quantitative coronary angiography was performed for a subset of 378 case-control pairs.ResultsThe majority of ST events occurred after 1 year (75%) and continued to occur for as long as 7.3 years. The clinical presentation of late/very late ST events was mainly myocardial infarction (66.7% ST-segment elevation myocardial infarction and 22.0% non–ST-segment elevation myocardial infarction); in-hospital mortality was 3.8%. A minority of patients (30%) with ST were receiving dual-antiplatelet therapy at the time of the event. Independent clinical correlates of late/very late ST were younger age, African-American race, current smoking, multivessel disease, longer stented length, overlapping stents, and percutaneous coronary intervention of vein graft lesions. Independent angiographic correlates for late/very late ST were lesions within the left anterior descending artery or a bypass graft, thrombus, and a larger residual diameter stenosis after the initial DES implantation. Despite the large sample of ST cases, all identified correlates of late/very late ST had weak associations with subsequent ST (all odds ratios <2.5).ConclusionsDespite a large sample of ST cases and use of limited matching to maximize the identification of predictive factors associated with late/very late ST, the variables associated with the development of late/very late ST were only weakly predictive of subsequent events. Additionally, a relatively low observed mortality rate of ST in this series may reflect a different pathophysiology of these late/very late events compared with acute/subacute ST. (Drug Eluting Stent Registry of Thrombosis [DESERT]; NCT00812552).     

Thrombotic Complications Associated With Early and Late Nonadherence to Dual Antiplatelet Therapy

ObjectivesThis study sought to assess the frequency and clinical impact of dual antiplatelet therapy (DAPT) nonadherence.BackgroundThere are limited data on the impact of DAPT nonadherence during the first year after a second-generation drug-eluting stent placement.MethodsAfter successful Endeavor zotarolimus-eluting stent implantation, 2,265 patients were enrolled in a registry with limited exclusions and monitored during 12 months of prescribed DAPT. Predictors of any nonadherence (ANA) at 6 months were analyzed by multivariable analysis, and the association between ANA at 6 or 12 months with the endpoints of death, myocardial infarction, and stent thrombosis was assessed.ResultsThe study population included 30% female patients, 34% with diabetes and 36% with acute coronary syndromes. ANA occurred in 208 patients (9.6%) before 6 months and 378 patients (18.5%) before 1 year. Major bleeding (odds ratio [OR]: 12.83, 95% confidence interval [CI]: 7.55 to 21.80, p < 0.001) was the only predictor of ANA at 6 months. In time-dependent analyses, ANA before 6 months was associated with an increased risk of death or myocardial infarction (7.6% vs. 3.0%, p < 0.001) and a numerical increase in stent thrombosis (2.0% vs. 0.9%, p = 0.12). After adjustment for baseline differences, ANA within 6 months remained associated with death or MI (OR: 1.95, 95% CI: 1.02 to 3.75). ANA occurring after 6 months did not increase the risk of subsequent ischemic events.ConclusionsDAPT ANA occurs frequently and is associated with increased risk for thrombotic complications if it occurs within the first 6 months. Major bleeding was a significant correlate of DAPT ANA within 6 months. (EDUCATE: The MEDTRONIC Endeavor Drug Eluting Stenting: Understanding Care, Antiplatelet Agents and Thrombotic Events; NCT01069003)     

Acute Thrombogenicity of a Durable Polymer Everolimus-Eluting Stent Relative to Contemporary Drug-Eluting Stents With Biodegradable Polymer Coatings Assessed Ex Vivo in a Swine Shunt Model

ObjectivesThis study sought to evaluate whether the permanent fluoropolymer-coated Xience Xpedition everolimus-eluting stent (Xience-EES) exhibits lower acute thrombogenicity compared with contemporary drug-eluting stents (DES) with biodegradable polymer coatings in an acute swine shunt model.BackgroundPrevious pre-clinical and clinical experience suggests that several factors may influence the predisposition for acute thrombus formation of polymer-coated DES, including stent design and the polymer coating technology. It remains unclear whether relevant differences exist with respect to acute thrombogenicity, particularly between current commercial stent designs using permanent polymers and those using biodegradable polymers.MethodsAn ex vivo carotid to jugular arteriovenous porcine shunt model involving a test circuit of 3 in-line stents, was used to test acute thrombogenicity, where Xience-EES (n = 24) was compared with 4 CE-marked DES with biodegradable polymer coatings (BioMatrix Flex, Synergy, Nobori, and Orsiro [n = 6 each]). After 1 h of circulation, platelet aggregation in whole mount stents was evaluated by confocal microscopy with immunofluorescent staining against dual platelet markers (CD61/CD42b) along with scanning electron microscopy.ResultsXience-EES showed the least percentage of thrombus-occupied area as compared with the biodegradable polymer-coated DES, with a significant difference compared with BioMatrix Flex and Synergy (mean differences: [BioMatrix Flex: 15.54, 95% confidence interval [CI]: 11.34 to 19.75, p < 0.001; Synergy: 8.64, 95% CI: 4.43 to 12.84, p < 0.001; Nobori: 4.22, 95% CI: -0.06 to 8.49, p = 0.055; Orsiro: 2.95, 95% CI: -1.26 to 7.15, p = 0.286). The number of cell nuclei on strut surfaces was also the least in Xience-EES, with a significant difference relative to BioMatrix Flex, Nobori, and Orsiro (mean ratios: BioMatrix Flex: 4.73, 95% CI: 2.46 to 9.08, p < 0.001; Synergy: 1.44, 95% CI: 0.75 to 2.76, p = 0.51; Nobori: 5.97, 95% CI: 3.11 to 11.44, p < 0.001; Orsiro: 5.16, 95% CI: 2.69 to 9.91, p < 0.001).ConclusionsXience-EES’s overall design confers acute thromboresistance relative to contemporary DES with biodegradable coatings, with less platelet aggregation versus BioMatrix Flex and Synergy, and less inflammatory cell attachment versus BioMatrix Flex, Nobori, and Orsiro, in an ex vivo swine shunt model, which lends support to reported clinical findings of lower early stent thrombosis.     

Drug-Coated Balloons Versus Second-Generation Drug-Eluting Stents for the Management of Recurrent Multimetal-Layered In-Stent Restenosis

ObjectivesThis study aimed to investigate the clinical outcomes of patients presenting with recurrent drug-eluting stent (DES) in-stent restenosis (ISR) treated with a second-generation DES or with a drug-coated balloon (DCB).BackgroundTo date, there are no reports of DCB treatment and limited data with regard to the efficacy of further DES implantation for recurrent ISR.MethodsBetween January 2008 and December 2013, 171 lesions were assessed for eligibility (82 lesions in the second-generation DES group and 89 lesions in the DCB group).ResultsAcute gain was greater in the second-generation DES group (second-generation DES, 2.09 ± 0.53 mm vs. DCBs, 1.60 ± 0.62 mm, p < 0.001). The rates of major adverse cardiac events were comparable (at 1 year, DES 14.0% vs. DCBs 12.3%; at 2 years, DES 28.8% vs. DCBs 43.5%, p = 0.21). Major adverse cardiac event rates were mainly driven by target lesion revascularization (at 1 year, DES 12.5% vs. DCBs 10.9%; at 2 years, DES 27.7% vs. DCBs 38.3%; p = 0.40). Definite scaffold thrombosis occurred in 2 patients (1 patient in each group). Multivariable analysis revealed ISR recurrence within 1 year (hazard ratio: 2.43, 95% confidence interval: 1.14 to 5.18, p = 0.02) and lesion length (per 10-mm increase) (hazard ratio: 1.15, 95% confidence interval: 1.00 to 1.32, p = 0.049) to be independent predictors of TLR.ConclusionsThe results after both treatments were equivalent. ISR recurrence within 1 year of the first reintervention and lesion length were independent predictors of future target lesion revascularization. Larger studies are required to confirm the late (>1 year) differences with regard to clinical outcomes.     

Stent Thrombosis: A Clinical Perspective

The invention of intracoronary stents greatly increased the safety and applicability of percutaneous coronary interventions. At this time, >1 million coronary stent implantations are performed each year in the United States. But together with the growing use of stents, stent thrombosis, the most feared complication after stent implantation, has emerged as an important entity to understand and prevent. Adjunct pharmacological therapy, stent design, and deployment technique have been adjusted ever since to reduce its occurrence. The current clinical overview of stent thrombosis ranges from its pathophysiology to current state-of-the-art technical and pharmacological recommendations to avoid this complication.     

Outcomes of Patients With Acute Myocardial Infarction Undergoing Percutaneous Coronary Intervention Receiving an Oral Anticoagulant and Dual Antiplatelet Therapy: A Comparison of Clopidogrel Versus Prasugrel From the TRANSLATE-ACS Study

ObjectivesThe purpose of this study was to determine whether bleeding risk varies depending on which P2Y₁₂ receptor inhibitor agent is used.BackgroundPrior studies have shown significant bleeding risk among patients treated with triple therapy (i.e., oral anticoagulant, P2Y₁₂ receptor inhibitor, and aspirin).MethodsWe evaluated patients with acute myocardial infarction (MI) treated with percutaneous coronary intervention (PCI) at 233 hospitals in the United States enrolled in the TRANSLATE-ACS (Treatment with Adenosine Diphosphate Receptor Inhibitors: Longitudinal Assessment of Treatment Patterns and Events After Acute Coronary Syndrome) study (April 2010 to October 2012). Using inverse probability-weighted propensity modeling, we compared 6-month adjusted risks of Bleeding Academic Research Consortium (BARC) bleeding, stratifying by whether or not bleeding was associated with rehospitalization among patients discharged on aspirin + anticoagulant + clopidogrel (triple-C), aspirin + anticoagulant + prasugrel (triple-P), aspirin + clopidogrel (dual-C), or aspirin + prasugrel (dual-P).ResultsOf 11,756 MI patients, 526 (4.5%) were discharged on triple-C, 91 (0.8%) on triple-P, 7,715 (66%) on dual-C, and 3,424 (29%) on dual-P. Compared with dual-therapy patients, triple-therapy patients had significantly higher any BARC-defined bleeding. Triple-P was associated with a greater risk of any BARC-defined bleeding events compared with triple-C. This finding was driven mostly by an increased risk of bleeding events that were patient-reported only and did not require rehospitalization. There were no significant differences in bleeding requiring rehospitalization between the triple-P and -C groups.ConclusionsAmong MI patients, the addition of an oral anticoagulant was associated with a significantly greater risk of any BARC-defined bleeding relative to dual antiplatelet therapy, regardless of which P2Y₁₂ receptor inhibitor was selected. Among patients on triple therapy, prasugrel use was associated with higher patient-reported–only bleeding, but not bleeding requiring rehospitalization, than clopidogrel-treated patients.     

Outcomes After Percutaneous Coronary Intervention With Stents in Patients Treated With Thoracic External Beam Radiation for Cancer

ObjectivesThe aim of this study was to assess outcomes after percutaneous coronary intervention (PCI) with stents in patients treated with thoracic external beam radiation therapy (EBRT).BackgroundThoracic EBRT for cancer is associated with long-term cardiotoxic sequelae. The impact of EBRT on patients requiring coronary stents is unclear.MethodsWe analyzed outcomes after PCI in cancer survivors treated with curative thoracic EBRT before and after stenting between 1998 and 2012. Reference groups were propensity-matched cohorts with stenting but no EBRT. Primary endpoint was target lesion revascularization (TLR), a clinical surrogate for restenosis. Secondary endpoints included myocardial infarction (MI) and cardiac and overall mortality.ResultsWe identified 115 patients treated with EBRT a median 3.6 years after stenting (group A) and 45 patients treated with EBRT a median 2.2 years before stenting (group B). Long-term mean TLR rates in group A (3.2 vs. 6.6%; hazard ratio: 0.6; 95% confidence interval: 0.2 to 1.6; p = 0.31) and group B (9.2 vs. 9.7%; hazard ratio: 1.2; 95% confidence interval: 0.4 to 3.4; p = 0.79) were similar to rates in corresponding control patients (group A: 1,390 control patients; group B: 439 control patients). Three years post-PCI, group A had higher overall mortality (48.6% vs. 13.9%; p < 0.001) but not MI (4.8% vs. 4.3%; p = 0.93) or cardiac mortality (2.3% vs. 3.6%; p = 0.66) rates versus control patients. There were no significant differences in MI, cardiac, or overall mortality rates in group B.ConclusionsThoracic EBRT is not associated with increased stent failure rates when used before or after PCI. A history of PCI should not preclude the use of curative thoracic EBRT in cancer patients or vice versa. Optimal treatment of cancer should be the goal.     

Randomized Comparison of Everolimus-Eluting Stents and Sirolimus-Eluting Stents in Patients With ST Elevation Myocardial Infarction: RACES-MI Trial

ObjectivesThe aim of the current study was to compare everolimus-eluting stents (EES) with sirolimus-eluting stents (SES) in patients undergoing primary angioplasty.BackgroundDrug-eluting stents may offer benefits in terms of repeat revascularization. However, as shown for first-generation drug-eluting stents, they may be counterbalanced by a potential higher risk of stent thrombosis, especially among patients with ST-segment elevation myocardial infarction (STEMI). No data have been reported so far on the long-term benefits and safety of the new generation of drug-eluting stents in STEMI.MethodsConsecutive STEMI patients admitted within 12 h of symptom onset and undergoing primary angioplasty and stent implantation at a tertiary center with 24-h primary percutaneous coronary intervention capability were randomly assigned to SES or EES. The primary endpoint was a major adverse cardiac event at 3-year follow-up. The secondary endpoints were death, reinfarction, definite or probable stent thrombosis, and target vessel revascularization at 3-year follow-up. No patient was lost to follow-up.ResultsFrom April 2007 to May 2009, 500 patients with STEMI were randomized to EES (n = 250) or SES (n = 250). No difference was observed in terms of baseline demographic and clinical characteristics between the groups. No difference was observed between the groups in terms of number of implanted stents per patient or total stent length. However, a larger reference diameter was observed with SES (3.35 ± 0.51 mm vs. 3.25 ± 0.51 mm, p = 0.001), whereas patients randomized to EES more often received glycoprotein IIb/IIIa inhibitors (54.4% vs. 42.4%, p = 0.006). Follow-up data were available in all patients (1,095 ± 159 days). No significant difference was observed between EES and SES in major adverse cardiac events (16% vs. 20.8%, adjusted hazard ratio [HR]: 0.75 [95% confidence interval (CI): 0.5 to 1.13], p = 0.17), cardiac death (4.4% vs. 5.6%, adjusted HR: 0.77 [95% CI: 0.35 to 1.71], p = 0.53), recurrent MI (6.4% vs. 10%, adjusted HR: 0.62 [95% CI: 0.33 to 1.16], p = 0.13), and target vessel revascularization (4.8% vs. 4.8%, adjusted HR: 1.00 [95% CI: 0.45 to 2.32], p = 0.99). However, EES was associated with a significant reduction in stent thrombosis (1.6% vs. 5.2%, adjusted HR: 0.3 [95% CI: 0.1 to 0.92], p = 0.035).ConclusionsThis study shows that among STEMI patients undergoing primary angioplasty, EES has similar efficacy as SES, but is associated with a significant reduction in stent thrombosis. (Randomized Comparison of Everolimus Eluting Stents and Sirolimus Eluting Stent in Patients With ST Elevation Myocardial Infarction [RACES-MI]; NCT01684982)     

Long-Term Outcomes of Neointimal Hyperplasia Without Neoatherosclerosis After Drug-Eluting Stent Implantation

ObjectivesThe aim of this study was to investigate the correlation between in-stent neointimal tissue without features of neoatherosclerosis and long-term clinical outcomes.BackgroundRecent studies have reported differential morphological characteristics of in-stent neointimal tissue assessed by optical coherence tomography (OCT).MethodsThe study population consisted of 336 patients with 368 drug-eluting stent-treated lesions. Patients received a follow-up OCT examination without any intervention. OCT-based neointima was categorized as homogeneous (n = 227 lesions in 208 patients), heterogeneous (n = 79 lesions in 73 patients), or layered (n = 62 lesions in 55 patients). Major adverse cardiac events (MACE) (a composite of cardiac death, nonfatal myocardial infarction, or target lesion revascularization) were assessed according to neointimal patterns during long-term clinical follow-up after OCT examination.ResultsThe time interval between stent implantation and OCT examination was similar among the 3 groups (p = 0.64). On multivariate logistic regression analysis, the significant determinant for the heterogeneous neointima was age (odds ratio [OR]: 1.037, 95% confidence interval [CI]: 1.007 to 1.068, p = 0.015) and an initial clinical presentation of acute coronary syndrome (OR: 1.967, 95% CI: 1.159 to 3.339, p = 0.012). The overall median follow-up duration for all patients after follow-up OCT examination was 31.0 months, and this was statistically different among the heterogeneous group (22.0 months), the homogeneous group (34.0 months), and the layered group (28.0 months, overall p = 0.002). MACE occurred more frequently in patients with heterogeneous neointima over a median 31-month follow-up period after OCT examination (13.7% vs. 2.9% in homogeneous vs. 7.3% in layered, p = 0.001). A propensity score–adjusted Cox regression analysis showed that independent risk factors for MACE were inclusion in the heterogeneous neointima (hazard ratio: 3.925, 95% CI: 1.445 to 10.662, p = 0.007) and minimal lumen cross-sectional area (hazard ratio: 0.368, 95% CI: 0.242 to 0.560, p < 0.001).ConclusionsDetermination of neointimal characteristics is helpful in predicting long-term clinical outcomes. Our data suggest that heterogeneous lesions are linked to poor long-term clinical prognoses.     

Long-Term Efficacy and Safety of Paclitaxel-Eluting Balloon for the Treatment of Drug-Eluting Stent Restenosis: 3-Year Results of a Randomized Controlled Trial

ObjectivesThis study sought to investigate the long-term comparative efficacy and safety of paclitaxel-eluting balloon (PEB), paclitaxel-eluting stent (PES), or balloon angioplasty (BA) for the treatment of drug-eluting stent restenosis.BackgroundThe optimal treatment of drug-eluting stent restenosis remains unknown. Although PEB has shown encouraging results, the long-term clinical efficacy and safety of PEB remains poorly defined.MethodsA total of 402 patients with clinically significant restenosis in limus-eluting stents were randomly assigned to receive PEB (n = 137), PES (n = 131), or BA (n = 134). For this analysis, PEB versus PES and PEB versus BA were compared. The primary efficacy and safety endpoints were target lesion revascularization and the composite of death or myocardial infarction.ResultsAt a median follow-up of 3 years, the risk of target lesion revascularization was comparable with PEB versus PES (hazard ratio [HR]: 1.46, 95% confidence interval [CI]: 0.91 to 2.33; p = 0.11) and lower with PEB versus BA (HR: 0.51, 95% CI: 0.34 to 0.74; p < 0.001). The risk of death/myocardial infarction tended to be lower with PEB versus PES (HR: 0.55, 95% CI: 0.28 to 1.07; p = 0.08), due to a lower risk of death (HR: 0.38, 95% CI: 0.17 to 0.87; p = 0.02). The risk of death/myocardial infarction was similar with PEB versus BA (HR: 0.96, 95% CI: 0.46 to 2.0; p = 0.91).ConclusionsAt 3 years, the use of PEB as compared with PES to treat patients with limus-eluting stent restenosis has similar efficacy and safety. PEB remains superior to BA. The sustained efficacy without trade-off in safety supports the role of PEB as treatment option for patients with drug-eluting stent restenosis. (Intracoronary Stenting and Angiographic Results: Drug Eluting Stent In-Stent Restenosis: 3 Treatment Approaches [ISAR-DESIRE 3]; NCT00987324)     

Predictors and Outcomes of Recurrent Stent Thrombosis: Results From a Multicenter Registry

ObjectivesThe aim of this study was to determine the incidence, predictors, and outcomes of recurrent stent thrombosis (rST).BackgroundPatients who had an initial stent thrombosis (ST) develop may be at high risk of rST.MethodsWe analyzed a multicenter California registry of angiographic definite ST at 5 academic hospitals from 2005 to 2013. A detailed review of the angiogram and procedure was performed of patients with and without rST.ResultsAmong 221 patients with a median follow-up of 3.3 years, definite or probable rST developed in 29, including 19 with angiographic definite rST. The cumulative hazard ratio (HR) of definite or probable rST was 16% at 1 year and 24% at 5 years, whereas the cumulative HR of angiographic definite rST was 11% at 1 year and 20% at 5 years. Despite similar angiographic results, patients who had rST develop had significantly greater peak creatine kinase at the time of initial ST (mean, 2,655 mg/dl vs. 1,654 mg/dl; p = 0.05) than those without rST. The 3-year rate of major adverse cardiovascular events was 50% for patients with rST compared with 22% for patients with a single ST (p = 0.01). After multivariable adjustment, independent predictors of definite/probable rST were age (HR: 1.4; 95 confidence interval [CI]: 1.1 to 1.8 per 10 years), bifurcation ST (HR: 4.4; 95% CI: 1.8 to 10.9), and proximal vessel diameter (HR: 1.8; 95% CI: 1.1 to 3.2 per millimeter).ConclusionsrST represents an important cause of long-term morbidity and mortality after an initial ST. Bifurcation ST and a larger proximal reference vessel diameter are independently associated with an increased risk of rST.     

Comparative Effectiveness and Safety of New-Generation Versus Early-Generation Drug-Eluting Stents According to Complexity of Coronary Artery Disease: A Patient-Level Pooled Analysis of 6,081 Patients

ObjectivesThe purpose of this study was to compare the 2-year safety and effectiveness of new- versus early-generation drug-eluting stents (DES) according to the severity of coronary artery disease (CAD) as assessed by the SYNTAX (Synergy between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery) score.BackgroundNew-generation DES are considered the standard-of-care in patients with CAD undergoing percutaneous coronary intervention. However, there are few data investigating the effects of new- over early-generation DES according to the anatomic complexity of CAD.MethodsPatient-level data from 4 contemporary, all-comers trials were pooled. The primary device-oriented clinical endpoint was the composite of cardiac death, myocardial infarction, or ischemia-driven target-lesion revascularization (TLR). The principal effectiveness and safety endpoints were TLR and definite stent thrombosis (ST), respectively. Adjusted hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated at 2 years for overall comparisons, as well as stratified for patients with lower (SYNTAX score ≤11) and higher complexity (SYNTAX score >11).ResultsA total of 6,081 patients were included in the study. New-generation DES (n = 4,554) compared with early-generation DES (n = 1,527) reduced the primary endpoint (HR: 0.75 [95% CI: 0.63 to 0.89]; p = 0.001) without interaction (p = 0.219) between patients with lower (HR: 0.86 [95% CI: 0.64 to 1.16]; p = 0.322) versus higher CAD complexity (HR: 0.68 [95% CI: 0.54 to 0.85]; p = 0.001). In patients with SYNTAX score >11, new-generation DES significantly reduced TLR (HR: 0.36 [95% CI: 0.26 to 0.51]; p < 0.001) and definite ST (HR: 0.28 [95% CI: 0.15 to 0.55]; p < 0.001) to a greater extent than in the low-complexity group (TLR p_int = 0.059; ST p_int = 0.013). New-generation DES decreased the risk of cardiac mortality in patients with SYNTAX score >11 (HR: 0.45 [95% CI: 0.27 to 0.76]; p = 0.003) but not in patients with SYNTAX score ≤11 (p_int = 0.042).ConclusionsNew-generation DES improve clinical outcomes compared with early-generation DES, with a greater safety and effectiveness in patients with SYNTAX score >11.