2016 ACC/AHA Guideline Focused Update on Duration of Dual Antiplatelet Therapy in Patients With Coronary Artery Disease: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines: An Update of the 2011 ACCF/AHA/SCAI Guideline for Percutaneous Coronary Intervention, 2011 ACCF/AHA Guideline for Coronary Artery Bypass Graft Surgery, 2012 ACC/AHA/ACP/AATS/PCNA/SCAI/STS Guideline for the Diagnosis and Management of Patients With Stable Ischemic Heart Disease, 2013 ACCF/AHA Guideline for the Management of ST-Elevation Myocardial Infarction, 2014 AHA/ACC Guideline for the Management of Patients With Non–ST-Elevation Acute Coronary Syndromes, and 2014 ACC/AHA Guideline on Perioperative Cardiovascular Evaluation and Management of Patients Undergoing Noncardiac Surgery

Extra-cellular expansion in the normal, non-infarcted myocardium is associated with worsening of regional myocardial function after acute myocardial infarction

BACKGROUND

Expansion of the myocardial extracellular volume (ECV) is a surrogate measure of focal/diffuse fibrosis and is an independent marker of prognosis in chronic heart disease. Changes in ECV may also occur after myocardial infarction, acutely because of oedema and in convalescence as part of ventricular remodelling. The objective of this study was to investigate changes in the pattern of distribution of regional (normal, infarcted and oedematous segments) and global left ventricular (LV) ECV using semi-automated methods early and late after reperfused ST-elevation myocardial infarction (STEMI).

METHODS

Fifty patients underwent cardiovascular magnetic resonance (CMR) imaging acutely (24 h-72 h) and at convalescence (3 months). The CMR protocol included: cines, T2-weighted (T2 W) imaging, pre-/post-contrast T1-maps and LGE-imaging. Using T2 W and LGE imaging on acute scans, 16-segments of the LV were categorised as normal, oedema and infarct. 800 segments (16 per-patient) were analysed for changes in ECV and wall thickening (WT).

RESULTS

From the acute studies, 325 (40.6%) segments were classified as normal, 246 (30.8%) segments as oedema and 229 (28.6%) segments as infarct. Segmental change in ECV between acute and follow-up studies (Δ ECV) was significantly different for normal, oedema and infarct segments (0.8 ± 6.5%, -1.78 ± 9%, -2.9 ± 10.9%, respectively; P < 0.001). Normal segments which demonstrated deterioration in wall thickening at follow-up showed significantly increased Δ ECV compared with normal segments with preserved wall thickening at follow up (1.82 ± 6.05% versus -0.10 ± 6.88%, P < 0.05).

CONCLUSION

Following reperfused STEMI, normal myocardium demonstrates subtle expansion of the extracellular volume at 3-month follow up. Segmental ECV expansion of normal myocardium is associated with worsening of contractile function.

The Use Pattern and Clinical Impact of New Antiplatelet Agents Including Prasugrel and Ticagrelor on 30-day Outcomes after Acute Myocardial Infarction in Korea: Korean Health Insurance Review and Assessment Data

Background and Objectives

Despite the favorable efficacy of new antiplatelet agents demonstrated in randomized controlled trials, their clinical implications in Korea are unclear. The purpose of this study was to investigate trends in antiplatelet agent use for acute myocardial infarction (AMI) and their impact on 30-day clinical outcomes.

Methods

AMI patients undergoing percutaneous coronary intervention between 2010 and 2015 were assessed using claim data from the Health Insurance Review and Assessment Service.

Results

The use of new antiplatelet agents has rapidly increased since 2013 and has been preferred over clopidogrel (Plavix; Bristol-Myers Squibb/Sanofi Pharmaceuticals) since 2015. Both prasugrel (Effient; Eli Lilly and Company) (odds ratio [OR], 0.45; 95% confidence interval [CI], 0.31–0.67; p<0.001) and ticagrelor (Brilinta; AstraZeneca Pharmaceuticals LP) (OR, 0.84; 95% CI, 0.71–0.98; p=0.032) had an independent effect on lowering 30-day mortality in a weighted multivariable logistic regression model. However, new antiplatelet agents had no significant effect on other clinical outcomes including myocardial infarction, stroke, bleeding, and readmission within 30 days.

Conclusion

The use of new antiplatelet agents is rapidly increasing, and they have been used more commonly than clopidogrel since 2015. We demonstrated that new antiplatelet agents have a favorable effect on reducing 30-day mortality in AMI patients in Korea.

Non-ST Elevation Acute Coronary Syndromes: A Comprehensive Review

Non-ST elevation-acute coronary syndrome (NSTE-ACS) includes NSTE myocardial infarction and unstable angina. This patient population forms approximately two-thirds of all hospital admissions for ACS in the United States each year and is associated with an in-hospital mortality of 5%. NSTE-ACS is primarily due to an acute change in the supply and demand balance of coronary perfusion and myocardial oxygen consumption, because of the significant coronary artery obstruction presenting as plaque rupture or erosion. Nevertheless, nonobstructive causes may lead to that same phenomenon by excessive myocardial oxygen demand or reduced coronary supply from hypotension, anemia, or sepsis, including transient coronary vasospasm and endocardial dysfunction. The recent clinical application of high-sensitivity troponin biomarker assays and computer tomography angiography shows promise for improving the diagnosis and the risk stratification of patients with angina symptoms. Implementation of recent updates to the American College of Cardiology/American Heart Association (ACC/AHA) guidelines on NSTE-ACS, especially regarding the selection and duration of antiplatelet therapy, have led to improvement in management and outcomes of this disease. Additionally, new adjunctive therapies and approaches to diagnosis and treatment are discussed. Despite the progress made in recent years in the diagnosis and management of NSTE-ACS, morbidity remains high and mortality is significant. Such a fact suggests that future research targeting prevention, early diagnosis, and intervention in these patients is warranted. This article provides a detailed overview of the most recent information on the pathophysiology, diagnosis, treatment, and prognosis of NSTE-ACS.

Clinical implications of blood-material interaction and drug eluting stent polymers in review

INTRODUCTION

Despite advances in drug-eluting stent (DES) technology, stent thrombosis (ST) remains the most feared complication with high morbidity and mortality. Areas covered: Stent related factors certainly play a role in the pathophysiology of ST and more recent data suggest coating technologies have the potential to favorable modify this risk though blood material interactions. Of the polymer coatings used in DES, fluorinated polymers in particular have shown significant promise in modifying the risk of ST through their preferential interactions with albumin which is believed to prevent the adhesion and aggregation of platelets to the stent surface and thus minimize thrombus formation. Preclinical data from the porcine arteriovenous fistula model and clinical data from large network meta-analysis support a role for fluorinated polymers in reducing ST. Expert commentary: The search for more biocompatible anti-thrombotic polymer coatings continues and it is likely that further modification of stent based surfaces will revolutionize the field of interventional cardiology by one day obviating the need for systemic anti-platelet therapies in patients receiving intravascular devices.

High risk of stent thrombosis in the first 6 months after coronary stenting: Do not discontinue clopidogrel early after ACS

OBJECTIVES

To estimate the incidence of stent thrombosis (ST) after early discontinuation of clopidogrel.

BACKGROUND

Premature discontinuation of clopidogrel is the strongest risk factor for ST. In contrast, recent studies suggest that shorter dual antiplatelet therapy (DAPT) can be discontinued as soon as 3 months after stenting. However, these studies included very few ACS patients and were not powered for ST. Hence, little is known about the occurrence of ST in high-risk populations when DAPT is discontinued early.

METHODS

This is a subanalysis of The Dutch ST Registry 437 ST cases (mainly first-generation DES and BMS). Acute coronary syndrome was the indication for index-PCI in 74% of the patients. Clopidogrel discontinuation rates in ST patients and matched controls were used to calculate the absolute incidence of ST after early clopidogrel discontinuation.

RESULTS

The overall rate of ST after cessation of clopidogrel was 4.6% (95%CI: 3.9-5.4%), as compared to 1.7% (95%CI: 1.5-1.9%) in patients who did not discontinue clopidogrel. The incidence of ST was 35.4% when clopidogrel was discontinued in the first 30 days after index-PCI declining to 11.7% when clopidogrel was discontinued in the first 180 days.

CONCLUSIONS

This dedicated ST registry shows that ST rates were very high when clopidogrel was discontinued before 6 months after index-PCI and therefore suggests that clopidogrel discontinuation in the first 6 months after ACS should be avoided.

Update on antithrombotic therapy after percutaneous coronary revascularisation

For relief of coronary obstruction, percutaneous coronary intervention has become a standard-of-care procedure over the past 40 years. Nonetheless, optimal outcomes after coronary stenting require careful attention to antithrombotic therapy. This review aims to summarise the current available evidence and discusses how to integrate scientific knowledge into clinical decisions. In recent years, improvement and modifications of drugs and devices have changed the field tremendously, and substantially benefitted patient outcomes. The key challenge of how to provide optimal protection against thrombotic events without excessive increases in bleeding risk has remained the same for decades. Alternative strategies with new drugs, both antiplatelet and anticoagulant agents, and new coronary stents will continue the journey to achieve this ultimate goal.

Ischemic Conditioning Attenuates Platelet-Mediated Thrombosis

Data obtained in both preclinical models and humans have revealed that the favorable cardiac consequences of ischemic conditioning extend beyond a direct effect on the cardiomyocyte. In the current review, we summarize our as-yet limited understanding of the complex relationships between ischemic conditioning, platelet activation–aggregation, and cardioprotection.

Effect of carboxylesterase 1 S75N on clopidogrel therapy among acute coronary syndrome patients

Carboxylesterase 1 (CES1) hydrolyzes the prodrug clopidogrel to an inactive carboxylic acid metabolite. The effects of CES1 S75N (rs2307240,C>T) on clopidogrel response among 851 acute coronary syndrome patients who came from the north, central and south of China were studied. The occurrence ratios of each endpoint in the CC group were significantly higher than in the CT + TT group for cerebrovascular events (14% vs 4.8%, p < 0.001, OR = 0.31), acute myocardial infarction (15.1% vs 6.1%, p < 0.001, OR = 0.37) and unstable angina (62.8% vs 37.7%, p < 0.001, OR = 0.36). The results showed that there was a significant association between CES1 S75N (rs2307240) and the outcome of clopidogrel therapy. Moreover, the frequency of the T allele of rs2307240 in acute coronary syndrome patients (MAF = 0.22) was more than four times higher than that in the general public (MAF = 0.05).

Interventions Supporting Long-term Adherence aNd Decreasing cardiovascular events (ISLAND): Pragmatic randomized trial protocol

BACKGROUND

Guidelines recommend cardiac rehabilitation and long-term use of cardiac medications for most patients who have had a myocardial infarction (MI), but adherence to these secondary prevention treatments is suboptimal.

METHODS

This is a multicenter, pragmatic, 3-arm randomized trial. Eligible patients (n = 2,742) with obstructive coronary artery disease are randomized post-MI to usual care or 1 of 2 intervention arms. Patients in the first intervention arm receive mail-outs sent on behalf of their cardiologist at 4, 8, 20, 32, and 44 weeks post-MI; content is designed to address determinants of adherence and facilitate discussion between the patient and their health care team. Patients in the second intervention arm receive mail-outs plus automated interactive voice response system telephone calls 2 weeks after each letter, as well as a telephone call by trained lay health workers if the interactive voice response system identifies challenges with adherence. Outcomes are assessed 12 months post-MI via patient self-report and administrative data sources. Co-primary outcomes are adherence to cardiac medications and completion of cardiac rehabilitation. Secondary outcomes include cardiovascular events and mortality. An embedded, theory-informed process evaluation will explore the mechanism of action; an economic evaluation is also planned.

CONCLUSIONS

We describe a complete program evaluation of a highly pragmatic, health-system intervention to support adherence to recommended treatments. Research ethics boards approved waiver of consent for patients enrolled in the trial with provision of multiple opportunities to opt out and a debrief at the time of outcome assessment. The methods used here may provide a model for similar interventions.

Gene variants in responsiveness to clopidogrel have no impact on clinical outcomes in Chinese patients undergoing percutaneous coronary intervention - A multicenter study

BACKGROUND

Gene variants contribute to variability in individual responsiveness to clopidogrel and influence cardiovascular outcomes in Caucasian patients with acute coronary syndrome (ACS). However, limited data is available in Asian populations.

METHODS

We resequenced 14 genes in metabolizing and activity pathway of clopidogrel in 138 patients with ACS and prospectively assessed the modulating effects of 13 variants possibly related to clopidogrel efficacy on one-year cardiovascular event occurrence in 5820 ACS patients after percutaneous coronary intervention (PCI). In addition, platelet aggregation rate was measured in 1084 participants and plasma levels of active metabolite were determined in 15 patients to test whether increasing clopidogrel maintenance doses increases active metabolite exposure.

RESULTS

No significant associations were found between any of the tested variants and risk of cardiovascular events (P>0.05), although CYP2C19*2 carriers had slightly higher on-treatment platelet aggregation rate and lower active metabolite exposure compared with that of non-carriers (Median [IQR] 51.49 [35.43-66.75] vs. 49.05 [32.36-63.38], P=0.012) (means±SD AUC, 22.84±5.00 vs. 35.05±12.34, P=0.008). Switching from 75mg daily clopidogrel to 150mg daily fully overcomes low exposure to clopidogrel active metabolite in CYP2C19*2 carriers (means±SD AUC, 32.35±8.65 vs. 35.05±12.34, P=0.314).

CONCLUSION

Different from Caucasian populations, genetic variants have no significant influence on clinical outcomes and have much milder effects on inhibition of platelet and active clopidogrel metabolite levels in Chinese patients with ACS after PCI, an effect which could be overcome with a dose escalation to 150mg daily.

Quality Improvement in Management of Acute Coronary Syndrome: Continuing Medical Education and Peer Coaching Improve Antiplatelet Medication Adherence and Reduce Hospital Readmissions

BACKGROUND

Reducing hospital readmissions and improving patient adherence to antiplatelet medications after an acute coronary syndrome (ACS) event are important goals for improving patient health and decreasing healthcare costs. Nearly half of patients will have a secondary event within 1 year of the initial ACS event. Quality improvement (QI) initiatives that include continuing medical education and peer coaching may improve physician practice patterns and, therefore, patient outcomes.

METHODS

This study evaluated the impact of a QI initiative on antiplatelet (P2Y12 inhibitor) medication adherence (measured via pharmacy fill rates postdischarge) and hospital readmissions.

RESULTS

Notable physician performance and patient-level changes included significant increases in antiplatelet medication counseling at hospital discharge (30%-57%; P < 0.0001), in P2Y12 inhibitor prescribing at hospital discharge (76%-84%; P = 0.02), and in patient fill rates for branded P2Y12 inhibitors (72%-100%; P = 0.0001). There were numerical trends toward lower rates of ACS-related rehospitalizations at 60 days postdischarge (from 11% to 7%; P = 0.15) and of all-cause rehospitalizations at 60 days (from 20% to 14%; P = 0.10).

CONCLUSION

Important in the rapidly evolving landscape of quality healthcare, QI involving continuing medical education and peer coaching demonstrably impacted physician performance and patient outcomes after an ACS event.

Personalizing antiplatelet prescribing using genetics for patients undergoing percutaneous coronary intervention

INTRODUCTION

Clopidogrel is commonly prescribed with aspirin to reduce the risk for adverse cardiovascular events after percutaneous coronary intervention (PCI). However, there is significant inter-patient variability in clopidogrel response. The CYP2C19 enzyme is involved in the biotransformation of clopidogrel to its pharmacologically active form, and variation in the CYP2C19 gene contributes to clopidogrel response variability. Areas covered. This article describes the impact of CYP2C19 genotype on clopidogrel pharmacokinetics, pharmacodynamics, and effectiveness. Examples of clinical implementation of CYP2C19 genotype-guided antiplatelet therapy for patients undergoing PCI are also described as are emerging outcomes data with this treatment approach. Expert commentary. A large clinical trial evaluating outcomes with CYP2C19 genotype-guided antiplatelet therapy after PCI is on-going. In the meantime, data from pragmatic and observational studies and smaller trials support improved outcomes with genotyping after PCI and use of alternative antiplatelet therapy in patients with a CYP2C19 genotype associated with reduced clopidogrel effectiveness.

Haplotype of platelet receptor P2RY12 gene is associated with residual clopidogrel on-treatment platelet reactivity

OBJECTIVE

To investigate a possible association between common variations of the P2RY12 and the residual clopidogrel on-treatment platelet reactivity after adjusting for the influence of CYP2C19 tested by thromboelastography (TEG).

METHODS

One hundred and eighty patients with acute coronary syndrome (ACS) treated with clopidogrel and aspirin were included and platelet function was assessed by TEG. Five selected P2RY12 single nucleotide polymorphisms (SNPs; rs6798347, rs6787801, rs6801273, rs6785930, and rs2046934), which cover the common variations in the P2RY12 gene and its regulatory regions, and three CYP2C19 SNPs (^*2,^*3,^*17) were genotyped and possible haplotypes were analyzed.

RESULTS

The high on-treatment platelet reactivity (HTPR) prevalence defined by a platelet inhibition rate <30% by TEG in adenosine diphosphate (ADP)-channel was 69 (38.33%). Six common haplotypes were inferred from four of the selected P2RY12 SNPs (denoted H₀ to H₅) according to the linkage disequilibrium R square (except for rs2046934). Haplotype H₁ showed a significantly lower incidence of HTPR than the reference haplotype (H₀) in the total study population while haplotypes H₁ and H₂ showed significantly lower incidences of HTPR than H₀ in the nonsmoker subgroup after adjusting for CYP2C19 effects and demographic characteristics. rs2046934 (T744C) did not show any significant association with HTPR.

CONCLUSIONS

The combination of common P2RY12 variations including regulatory regions rather than rs2046934 (T744C) that related to pharmacodynamics of clopidogrel in patients with ACS was independently associated with residual on-clopidogrel platelet reactivity. This is apart from the established association of the CYP2C19. This association seemed more important in the subgroup defined by smoking.

Successful percutaneous coronary intervention in the setting of an aberrant left coronary artery arising from the right coronary cusp in a patient with acute coronary syndrome: a case report

BACKGROUND

An aberrant origin of the left coronary artery (LCA) from the right coronary cusp (RCC) is an extremely rare congenital anomaly. We here report on successful percutaneous coronary intervention (PCI) in a patient presenting with acute coronary syndrome and an aberrant origin of the LCA from the RCC.

CASE PRESENTATION

A 50-year-old man presented at our emergency department with recurrent resting chest pain. Following unsuccessful attempts at visualizing the left coronary artery using Judkins left and Amplatz catheters, an aortogram using a pigtail catheter suggested anomalous left coronary artery origin and showed a significant occlusive lesion at proximal left anterior descending artery. A Judkins right 4 guiding catheter was placed around the left coronary ostium and exchanged for a Judkins left 3.5 guiding catheter after introducing a .014" coronary long wire into the left circumflex artery. With excellent angiographic visualization and guide support, a drug-eluting stent was then successfully implanted. Cardiac computed tomography (CT) demonstrated left coronary artery origin from right coronary cusp.

CONCLUSION

This report presents a case of LCA originating from the RCC accompanied with acute coronary syndrome that was treated with successful PCI.

Dual Antiplatelet Therapy Beyond One Year in Patients After Stent Placement: A Review

PURPOSE

To review the evidence on the safety and efficacy of the continued use of dual antiplatelet therapy (DAPT) beyond 12 months after stent placement in patients following an acute coronary syndrome (ACS) event.

SUMMARY

Recently, the American College of Cardiology (ACC) and the American Heart Association (AHA) released a focused update on the duration of DAPT in patients with coronary artery disease (CAD). The update makes new recommendations about the duration of DAPT in light of recently performed studies investigating this topic. In regard to patients after an ACS event, the update states it is reasonable to continue DAPT beyond 1 year if these patients are not at a high risk of bleeding and had no overt bleeding while on DAPT. Several trials have been released which aim to provide information about the correct duration of DAPT after an ACS event.

CONCLUSION

Recent trials have shown a benefit of prolonged (beyond 12 months) DAPT in preventing recurrent cardiovascular (CV) events in patients, mostly in patients who have had a previous myocardial infarction (MI). These benefits must be weighed with the elevated risks of bleeding.

Contemporary Atrial Fibrillation Management: A Comparison of the Current AHA/ACC/HRS, CCS, and ESC Guidelines

In this article we compare and contrast the current recommendations, and highlight the important differences, in the American College of Cardiology/American Heart Association/Heart Rhythm Society, European Society of Cardiology, and Canadian Cardiovascular Society atrial fibrillation (AF) guidelines. Although many of the recommendations of the various societies are similar, there are important differences in the methodologies underlying their development and the specific content. Specifically, key differences can be observed in: (1) the definition of nonvalvular AF, which subsequently affects anticoagulation choices and candidacy for non-vitamin K antagonist oral anticoagulants; (2) the symptom score used to guide management decisions and longitudinal patient profiling; (3) the stroke risk stratification algorithm used to determine indications for oral anticoagulant therapy; (4) the role of acetylsalicylic acid in stroke prevention in AF; (5) the antithrombotic regimens used in the context of coronary artery disease, acute coronary syndromes, and percutaneous coronary intervention; (6) the rate control target and medications recommended to achieve the target; and (7) the role of "first-line" catheter ablation, open surgical ablation, and left atrial appendage exclusion.

Prognostic value of plasma DPP4 activity in ST-elevation myocardial infarction

Background

Dipeptidyl peptidase-4 (DPP4) regulates blood glucose levels and inflammation, and it is also implicated in the pathophysiological process of myocardial infarction (MI). Plasma DPP4 activity (DPP4a) may provide prognostic information regarding outcomes for ST-segment elevation MI (STEMI) patients.

Methods

Blood samples were obtained from 625 consecutively admitted, percutaneous coronary intervention-treated STEMI patients with a mean age of 57 years old. DPP4a was quantified using enzymatic assays.

Results

The median follow-up period was 30 months. Multivariate Cox-regression analyses (adjusted for confounding variables) showed that a 1 U/L increase of DPP4a did not associate with risks of major adverse cardiac or cerebrovascular events (MACCE), cardiovascular mortality, MI, heart failure readmission, stroke, non-cardiovascular mortality and repeated revascularization. However, in a subset of 149 diabetic STEMI patients, DPP4a associated with an increased risk of MACCE (HR 1.16; 95% CI 1.04–1.30; p = 0.01).

Conclusions

DPP4a did not associate with cardiovascular events and non-cardiovascular mortality in non-diabetic STEMI patients. However, DPP4a may be associated with future MACCE in diabetic STEMI patients.

Trial registration NCT03046576, registered on 5 February, 2017, retrospectively registered

Electronic supplementary material

The online version of this article (doi:10.1186/s12933-017-0553-3) contains supplementary material, which is available to authorized users.

Previous hypertensive hemorrhage increases the risk for bleeding and ischemia for PCI patients on dual antiplatelet therapy

OBJECTIVES

The use of antiplatelet therapy after intracerebral hemorrhage remains controversial, while the use of dual antiplatelet therapy (DAPT) is required after cardiac stenting. In this study, we examine the risk of bleeding and ischemic events for PCI patients with a history of hypertensive hemorrhage on DAPT.

METHODS

A total of 128 cases and 153 controls were selected from Chinese patients with cardiac stenting on dual anti-platelet therapy for a single-center retrospective case-control study. Patients with a history of hypertensive hemorrhage were selected for the case group, while patients with a history of hypertension were chosen as control. All patients were on aspirin 100 mg and clopidogrel 75 mg after cardiac stenting, and were followed for a duration of 12-48 months. The primary outcomes were intracerebral hemorrhage, major bleeding, and major adverse cardiovascular and cerebrovascular events.

RESULTS

A history of previous hypertensive hemorrhage was not found to be a risk factor for intracerebral hemorrhage and major bleeding while on dual anti-platelet therapy. However, a history of either hypertensive hemorrhage or coronary artery disease was independently found to be risk factors for major adverse cardiovascular and cerebrovascular events. On sub-group analysis, patients with a history of hypertensive hemorrhage within 12 months were found to be at higher risk for bleeding on dual anti-platelet therapy, while patients with history of hypertensive hemorrhage outside of 12 months on dual anti-platelet therapy did not have the same increased risk.

CONCLUSION

A history of hypertensive hemorrhage and coronary heart disease were two independent risk factors for major adverse cardiovascular and cerebrovascular events in PCI patients taking DAPT. A history of hypertensive hemorrhage less than 12 months had an increased risk for recurrent intracerebral hemorrhage and major bleeding in PCI patients taking DAPT.

Antiplatelet Therapy and Clinical Outcomes Following Myocardial Infarction Among Patients in a U.S. Employer-Based Insurance Database

BACKGROUND

Estimates of residual cardiovascular risks among patients who have experienced a recent acute myocardial infarction (MI) are predominantly derived from secondary prevention trial populations, patient registries, and population-based cohorts.

OBJECTIVE

To generate real-world evidence of antiplatelet treatment and recurrent events following MI in patients on antiplatelet treatment among commercial, employer-based insured patients in a large administrative database.

METHODS

This was a retrospective cohort claims database study using the Truven Health MarketScan Commercial Claims and Encounters and Medicare Supplemental databases between 2007-2011. Patients with an acute MI hospitalization with a discharge date between 2008 and 2010 were included. Excluded were those patients with documentation of stroke, transient ischemic attack (TIA), or severe bleeding at or before index hospitalization and with concomitant use of anticoagulant therapy following index hospitalization. Patients treated with clopidogrel following the index MI hospitalization were followed up to 1 year for repeat MI, stroke, and coronary revascularization.

RESULTS

Among 33,943 post-MI continuous clopidogrel users without history of stroke, TIA, or bleeding, 22% had diabetes, whereas angina and renal impairment were less prevalent (5% and 7%, respectively). Over the 1-year follow-up, 2.4% experienced a repeat MI or stroke, and 8.2% underwent coronary revascularization. Angina, diabetes, and renal impairment were associated with elevated 1-year risk of repeat MI or stroke.

CONCLUSIONS

This study suggests that there is residual cardiovascular risk, although relatively low, in an insured, secondary prevention population on antiplatelet treatment following an MI. In patients with MI, identifying angina, diabetes, and renal impairment may aid risk stratification and guide the effective management of these higher-risk patients.

DISCLOSURES

Funding for this research was provided by Merck & Co. Although Merck & Co. formally reviewed a penultimate draft, the opinions expressed are those of the authorship and may not necessarily reflect those of the company. Reed Chase, Wu, Mavros, Heithoff, and Hanson are employees of Merck Sharp & Dohme, a subsidiary of Merck & Co., and may own stock and/or hold stock options in the company. Patel was an employee of Merck & Co. during the conduct of this study and preparation of the manuscript. Simpson is a paid consultant for Merck, Pfizer, and Amgen and has received speaker's fees from Merck and Pfizer. Study concept and design were contributed by all authors except Hanson. Heifhoff and Patel collected the data, and data interpretation was performed by Simpson, Mavros, Patel, Wu, and Hanson. The manuscript was written by Hanson, Mavros, and Patel and revised by Heithoff, Wu, Simpson, and Reed Chase.

Surgery after drug-eluting stent implantation: it's not all doom and gloom!

Up to 15-23% of the patients with percutaneous coronary intervention (PCI) and drug-eluting stent (DES) implantation need a surgical procedure <12 months from PCI. Perioperative risk stratification in these patients is challenging and should take into account many individual clinical and anatomic variables, along with the intrinsic surgical risk for ischemic and bleeding events. The presence of DES has always been considered as a harbinger of doom. In fact, DES are associated with delayed vascular healing and require longer dual antiplatelet treatment. Perioperative pharmacologic management in those patients is intricate because of the tradeoff between the increased thrombotic risk associated with premature DAPT discontinuation and the increased risk of bleeding in the presence of antithrombotics. Whilst most of the studies agree upon the inverse relationship between time from stenting to surgery and cardiac risk, more recent data challenge the previous belief that surgery should be deferred at least 12 months after DES implantation and this safety window could be shortened to <6 months or even less with new-generation DES. The aim of this brief commentary is to critically review available data about cardiac risk associated with surgery in patients with coronary drug-eluting stents.

Preoperative aspirin use and acute kidney injury after cardiac surgery: A propensity-score matched observational study

BACKGROUND

The association between preoperative aspirin use and postoperative acute kidney injury (AKI) in cardiovascular surgery is unclear. We sought to evaluate the effect of preoperative aspirin use on postoperative AKI in cardiac surgery.

METHODS

A total of 770 patients who underwent cardiovascular surgery under cardiopulmonary bypass were reviewed. Perioperative clinical parameters including preoperative aspirin administration were retrieved. We matched 108 patients who took preoperative aspirin continuously with patients who stopped aspirin more than 7 days or did not take aspirin for the month before surgery. The parameters used in the matching included variables related to surgery type, patient's demographics, underlying medical conditions and preoperative medications.

RESULTS

In the first seven postoperative days, 399 patients (51.8%) developed AKI, as defined by the Kidney Disease Improving Global Outcomes (KDIGO) criteria and 128 patients (16.6%) required hemodialysis. Most patients took aspirin 100 mg once daily (n = 195, 96.5%) and the remaining 75 mg once daily. Multivariable analysis showed that preoperative maintenance of aspirin was independently associated with decreased incidence of postoperative AKI (odds ratio [OR] 0.46, 95% confidence interval [CI] 0.21-0.98, P = 0.048; after propensity score matching: OR 0.39, 95% CI 0.22-0.67, P = 0.001). Preoperative maintenance of aspirin was associated with less incidence of AKI defined by KDIGO both in the entire and matched cohort (n = 44 [40.7%] vs. 69 [63.9%] in aspirin and non-aspirin group, respectively in matched sample, relative risk [RR] 0.64, 95% CI 0.49, 0.83, P = 0.001). Preoperative aspirin was associated with decreased postoperative hospital stay after matching (12 [9-18] days vs. 16 [10-25] in aspirin and non-aspirin group, respectively, P = 0.038). Intraoperative estimated or calculated blood loss using hematocrit difference and estimated total blood volume showed no difference according to aspirin administration in both entire and matched cohort.

CONCLUSIONS

Preoperative low dose aspirin administration without discontinuation was protective against postoperative AKI defined by KDIGO criteria independently in both entire and matched cohort. Preoperative aspirin was also associated with decreased hemodialysis requirements and decreased postoperative hospital stay without increasing bleeding. However, differences in AKI and hospital stay were not associated with in-hospital mortality.

A Critical Appraisal of Aspirin in Secondary Prevention: Is Less More?

Aspirin represents the sine qua non for antiplatelet pharmacotherapy in patients with cardiovascular diseases because of its well-established role in secondary prevention and its widespread availability and affordability. Historical studies, conducted in an era that bears little resemblance to contemporary clinical practice, demonstrated large reductions in thrombotic risk when aspirin was compared with placebo, thus forming the evidence base promulgated in practice guidelines and recommendations. P2Y₁₂ inhibitors have mostly been studied in addition to aspirin; dual-antiplatelet therapy proved superiority compared with aspirin monotherapy for the prevention of ischemic events, despite increased bleeding risks. An alternative approach currently under investigation includes evaluation of single-antiplatelet therapy with P2Y₁₂ inhibitors alone versus dual-antiplatelet therapy after acute coronary syndromes or coronary stent implantation. As the availability of more effective antiplatelet agents increases, it is time to revisit the existing and long-standing paradigm supporting aspirin use for secondary prevention of atherothrombotic events. Ongoing trials will provide new evidence whether the less-is-more strategy is justified.

Bioresorbable Scaffold: The Emerging Reality and Future Directions

In the era of drug-eluting stents, large-scale randomized trials and all-comer registries have shown excellent clinical results. However, even the latest-generation drug-eluting stent has not managed to address all the limitations of permanent metallic coronary stents, such as the risks of target lesion revascularization, neoatherosclerosis, preclusion of late lumen enlargement, and the lack of reactive vasomotion. Furthermore, the risk of very late stent, although substantially reduced with newer-generation drug-eluting stent, still remains. These problems were anticipated to be solved with the advent of fully biodegradable devices. Fully bioresorbable coronary scaffolds have been designed to function transiently to prevent acute recoil, but have retained the capability to inhibit neointimal proliferation by eluting immunosuppressive drugs. Nevertheless, long-term follow-up data of the leading bioresorbable scaffold (Absorb) are becoming available and have raised a concern about the relatively higher incidence of scaffold thrombosis. To reduce the rate of clinical events, improvements in the device, as well as implantation procedure, are being evaluated. This review will focus on the current CE-mark approved bioresorbable scaffolds, their basic characteristics, and clinical results. In addition, we summarize the current limitations of bioresorbable scaffold and their possible solutions.

Characteristics of Earlier Versus Delayed Presentation of Very Late Drug-Eluting Stent Thrombosis: An Optical Coherence Tomographic Study

Background

The pathophysiology underlying very late drug‐eluting stent (DES) thrombosis is not sufficiently understood. Using optical coherence tomography, we investigated characteristics of very late stent thrombosis (VLST) according to different onset times.

Methods and Results

A total of 98 patients from 10 South Korean hospitals who underwent optical coherence tomography for evaluation of very late DES thrombosis were retrospectively included in analyses. VLST occurred at a median of 55.1 months after DES implantation. All patients were divided into 2 equal groups of earlier versus delayed presentation of VLST, according to median onset time. In total, 27 patients were treated with next‐generation DES and 71 with first‐generation DES. Based on optical coherence tomography findings at thrombotic sites, main VLST mechanisms were as follows, in descending order: neoatherosclerosis (34.7%), stent malapposition (33.7%), and uncovered struts without stent malapposition or evagination (24.5%). Compared with patients with earlier VLST, patients with delayed VLST had lower frequency of uncovered struts without stent malapposition or evagination (34.7% versus 14.3%, respectively; P=0.019). Conversely, the frequency of neoatherosclerosis was higher in patients with delayed versus earlier VLST (44.9% versus 24.5%, respectively; P=0.034). The frequency of stent malapposition was not different between patients with earlier and delayed VLST (34.7% versus 32.7%, respectively; P=0.831). The frequency of stent malapposition, evagination, and uncovered struts was still half of delayed VLST.

Conclusions

The pathological mechanisms of very late DES thrombosis changed over time. Delayed neointimal healing remained a substantial substrate for VLST, even long after DES implantation.

Optimal duration of dual antiplatelet therapy following percutaneous coronary intervention: protocol for an umbrella review

INTRODUCTION

Although dual antiplatelet therapy (DAPT) is routinely given to patients after percutaneous coronary intervention (PCI) with stenting, the optimal duration is unknown. Recent evidence indicates there may be benefits in extending the duration beyond 12 months but such decisions may increase the risk of bleeding. Our objective is to provide a comprehensive overview of the literature for clinicians and policymakers via an umbrella review assessing the optimal duration of DAPT.

METHODS AND ANALYSIS

We will perform a comprehensive search of the published and grey literature for systematic reviews involving randomised controlled trials (RCTs) assessing the optimal duration of DAPT following PCI with stenting. The intervention of interest is extended DAPT (beyond 12 months) compared with short-term DAPT (6-12 months). Studies will be selected for inclusion by two reviewers, and the quality will be assessed. The primary outcomes of interest are all-cause mortality and cardiovascular mortality. Secondary outcomes will be bleeding (major, minor and gastrointestinal), urgent target vessel revascularisation, major adverse cardiovascular events, myocardial infarction, stroke and stent thrombosis. Outcomes will be assessed while on DAPT and after withdrawal of DAPT. Data will be summarised with respect to the number of included RCTs, number of participants, effect estimates and heterogeneity. Data will be reported separately based on patient demographics, procedural parameters (eg, stent types, lesion complexity and concurrent disease) and clinical presentation (eg, acute coronary syndromes, infarct type).

ETHICS AND DISSEMINATION

Our umbrella review aims to provide a comprehensive overview of the benefits and harms associated with extending DAPT beyond 12 months following PCI with stenting. The results of this review will inform clinical and policy decisions regarding the optimal treatment duration and reimbursement of DAPT following PCI with stenting. Results will be disseminated through a peer-reviewed publication and conference presentations. Ethics approval is not required for this study.

TRIAL REGISTRATION NUMBER

CRD42016047735.

Duration of dual antiplatelet therapy in acute coronary syndrome

Despite a large volume of evidence supporting the use of dual antiplatelet therapy in patients with acute coronary syndrome, there remains major uncertainty regarding the optimal duration of therapy. Clinical trials have varied markedly in the duration of therapy, both across and within trials. Recent systematic reviews and meta-analyses suggest that shorter durations of dual antiplatelet therapy are superior because the avoidance of atherothrombotic events is counterbalanced by the greater risks of excess major bleeding with apparent increases in all-cause mortality with longer durations. These findings did not show significant heterogeneity according to whether patients had stable or unstable coronary heart disease. Moreover, the potential hazards and benefits may differ when applied to the general broad population of patients encountered in everyday clinical practice who have markedly higher bleeding and atherothrombotic event rates. Clinicians lack definitive information regarding the duration of therapy in patients with acute coronary syndrome and risk scores do not appear to be sufficiently robust to address these concerns. We believe that there is a pressing need to undertake a broad inclusive safety trial of shorter durations of therapy in real world populations of patients with acute coronary syndrome. The clinical evidence would further inform future research into strategies for personalised medicine.

2016 AHA/ACC Guideline on the Management of Patients With Lower Extremity Peripheral Artery Disease: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines

Since 1980, the American College of Cardiology (ACC) and American Heart Association (AHA) have translated scientific evidence into clinical practice guidelines with recommendations to improve cardiovascular health. These guidelines, based on systematic methods to evaluate and classify evidence, provide a cornerstone of quality cardiovascular care.

In response to reports from the Institute of Medicine1 ,2 and a mandate to evaluate new knowledge and maintain relevance at the point of care, the ACC/AHA Task Force on Clinical Practice Guidelines (Task Force) modified its methodology.3 –5 The relationships among guidelines, data standards, appropriate use criteria, and performance measures are addressed elsewhere.5

Ticagrelor and Rosuvastatin Have Additive Cardioprotective Effects via Adenosine

BACKGROUND

Ticagrelor inhibits the equilibrative-nucleoside-transporter-1 and thereby, adenosine cell re-uptake. Ticagrelor limits infarct size (IS) in non-diabetic rats and the effect is adenosine-dependent. Statins, via ecto-5'-nucleotidase activation, also increase adenosine levels and limit IS.

HYPOTHESIS

Ticagrelor and rosuvastatin have additive effects on myocardial adenosine levels, and therefore, on IS and post-reperfusion activation of the NLRP3-inflammasome.

METHODS

Diabetic ZDF rats received via oral gavage; water (control), ticagrelor (150 mg/kg/d), prasugrel (7.5 mg/kg/d), rosuvastatin (5 mg/kg/d), ticagrelor + rosuvastatin and prasugrel + rosuvastatin for 3d. On day 4, rats underwent 30 min coronary artery occlusion and 24 h of reperfusion. Two additional groups received, ticagrelor + rosuvastatin or water in combination with CGS15943 (CGS, an adenosine receptor antagonist, 10 mg/kg i.p. 1 h before ischemia).

RESULTS

Both ticagrelor and rosuvastatin increased myocardial adenosine levels with an additive effect of the combination whereas prasugrel had no effect. Similarly, both ticagrelor and rosuvastatin significantly reduced IS with an additive effect of the combination whereas prasugrel had no effect. The effect on IS was adenosine dependent as CGS15943 reversed the effect of ticagrelor + rosuvastatin. The ischemia-reperfusion injury increased myocardial mRNA levels of NLRP3, ASC, IL-1β and IL-6. Ticagrelor and rosuvastatin, but not prasugrel, significantly decreased these pro-inflammatory mediators with a trend to an additive effect of the combination. The combination also increased the levels of anti-inflammatory 15-epilipoxin A₄.

CONCLUSIONS

Ticagrelor and rosuvastatin when given in combination have an additive effect on local myocardial adenosine levels in the setting of ischemia reperfusion. This translates into an additive cardioprotective effect mediated by adenosine-induced effects including downregulation of pro- but upregulation of anti-inflammatory mediators.

Myocardial Infarction Risk After Discontinuation of Thienopyridine Therapy in the Randomized DAPT Study (Dual Antiplatelet Therapy)

BACKGROUND

Thienopyridine plus aspirin beyond 1 year after coronary stenting reduces myocardial infarction (MI) risk and increases bleeding risk in comparison with aspirin alone. The hazard associated with late thienopyridine discontinuation and risk factors for MI after discontinuation are poorly defined.

METHODS

In the DAPT Study (Dual Antiplatelet Therapy), after percutaneous coronary intervention and 12 months of thienopyridine (clopidogrel or prasugrel) plus aspirin, eligible patients remained on aspirin and were randomly assigned to continued thienopyridine versus placebo for 18 months. At 30 months, patients stopped the study drug and were observed for 3 months. Cumulative incidence of MI was assessed over 3 months after randomization (months 12-15) and 3 months after study drug discontinuation (months 30-33). The MI hazard for each of these periods was assessed across randomized treatment arms and by DAPT score values <2 or ≥2.

RESULTS

Among the 11 648 randomly assigned patients, the monthly cumulative incidence of MI was lower with continued thienopyridine versus placebo at 12 to 15 months (0.12% versus 0.37%, P<0.001, in all patients; 0.13% versus 0.27%, P=0.02, in patients not treated with paclitaxel-eluting stents), and higher at 30 to 33 months (0.30% versus 0.15%, P=0.013, in all patients; in patients without paclitaxel-eluting stents, 0.18% versus 0.17%, P=0.91). The majority of MIs in both time periods (74% and 76%) were not related to stent thrombosis. After multivariable adjustment, treatment arm independently predicted MI at months 12 to 15 (P<0.001) and 30 to 33 (P=0.011). During months 12 to 15, patients with DAPT scores <2 or ≥2 both had lower rates of MI with continued thienopyridine (MI monthly incidence 0.16% versus 0.51%, P<0.001, for scores ≥2; 0.08% versus 0.24%, P=0.012, for scores<2, interaction P=0.064).

CONCLUSIONS

Discontinuing thienopyridine after either 12 or 30 months is associated with an early increase in MI risk, mainly unrelated to stent thrombosis; the magnitude of risk is highest in the earlier time frame, and lower in patients not treated with paclitaxel-eluting stents. Although higher DAPT scores identify patients with greater absolute ischemic benefit (relative to bleeding harm) with continued thienopyridine therapy, discontinuation at 12 months increases MI hazard regardless of DAPT score group.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00977938.

What is the optimal duration of dual antiplatelet therapy after percutaneous coronary intervention with drug-eluting stent implantation?

PURPOSE

Published evidence on varying durations of dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI) with implantation of a drug-eluting stent (DES) is reviewed.

SUMMARY

A systematic literature search identified 13 randomized controlled trials and eight meta-analyses evaluating patient outcomes of standard (12-month) versus shorter or longer courses of DAPT (aspirin and a P2Y12 inhibitor, usually clopidogrel) after PCI with DES implantation. Evaluated outcomes included cardiovascular (CV) events, stent thrombosis, bleeding events, and mortality. Overall, the available evidence indicates that DAPT for periods of 3-6 months was as effective as DAPT courses of 12 months or more in reducing rates of CV events and stent thrombosis and was associated with similar or lower rates of bleeding; however, the quality of that evidence was limited by methodological shortcomings, including open-label study designs and low overall event rates. Relative to 12-month DAPT, DAPT for longer periods (up to four years) was associated with decreased rates of CV events and stent thrombosis (the reduction in thrombosis risk was greatest in patients who received a first-generation DES) but also increased bleeding events; all-cause mortality appears to be similar or potentially higher with extended-duration DAPT.

CONCLUSION

DAPT for a period of 12 months should continue to be the standard recommendation after PCI with DES implantation. Routine use of shorter- or longer-duration DAPT should be discouraged; if such therapy is considered, prescribing decisions should be based on individual patient risk factors.

Hyperglycemia effect on coronary disease in patients with metabolic syndrome evaluated by intracoronary ultrasonography

INTRODUCTION

Metabolic syndrome (MS) is characterized by dyslipidemia, central obesity, hypertension and hyperglycemia. However, type 2 diabetes mellitus (T2DM) may or may not be present in metabolic syndrome. MS and T2DM are considered important cardiovascular risk factors, but the role of hyperglycemia in coronary disease is still contested in the literature. Therefore, we decided to evaluate the effect of hyperglycemia on the severity of coronary disease in MS patients, with or without T2DM, submitted to coronary angiography (CA) and intravascular ultrasonography (IVUS).

MATERIALS AND METHODS

This is a cross sectional, observational study with 100 MS patients (50% with T2DM), 60% male. All of the patients had been referred for CA procedures. The obstruction was considered severe when stenosis was greater than 70% and moderate if it was between 50-69%. Patients detected with a moderate obstruction by CA were indicated to IVUS. A minimal luminal area of less than 4mm2 detected by IVUS was also considered severe. IDF criteria were used to define Metabolic Syndrome and T2DM diagnosis was defined according to the American Diabetes Association criteria. Student's t-test and Pearson Chi-square were used for statistical analysis, considering p < 0.05 statistically significant.

RESULTS AND DISCUSSION

The majority of T2DM patients presented severe arterial lesions (74% vs 22%, p<0.001). Using CA procedure, 12% of T2DM had moderate obstructions, compared to 38% of the non-diabetic group (p< 0.05). 8% of patients with moderate lesions by CA were diagnosed with a luminal area less than 4mm2 using IVUS. This luminal area was significantly smaller in the T2DM group than in the control group (3.8mm2 ± 2.42. vs 4.6mm2 ± 2.58, p = 0.03).

CONCLUSION

Patients with MS and T2DM submitted to angiography and IVUS, had more severe coronary lesions compared to MS patients without diabetes. This finding suggests that beyond insulin resistance that is present in MS, hyperglycemia may also play a role in the development of atherosclerotic disease. IVUS was useful for diagnosing 8% of severe cases initially considered to be moderate obstructions when using just CA in this scenario.